This document discusses several topics related to food microbiology. It begins by listing intrinsic and extrinsic factors that affect microbial growth in food, such as pH, moisture content, temperature, and nutrients. It then discusses how these various factors like pH, water activity, and salt/sugar concentrations specifically impact the growth of microorganisms like bacteria, molds, and yeasts. The document also covers chemical changes caused by microbes in different foods, how microbes are classified based on structure and temperature tolerance, and provides examples of diseases caused by different viruses.
Foodborne diseases pose a significant threat to public health worldwide. They can be caused by bacteria, viruses, parasites or toxins entering the body through contaminated food. Major pathogens like Salmonella, E. coli and Campylobacter cause foodborne infections and intoxications with symptoms like diarrhea and vomiting. In developing countries, poor hygienic practices and lack of surveillance exacerbate the foodborne disease burden. Proper food safety practices and surveillance systems are needed to reduce illnesses and deaths from these preventable diseases.
This document discusses bacterial food poisoning, describing common causative agents, symptoms, pathogenesis, and methods of diagnosis. The major bacterial causes outlined are Staphylococcus aureus, Bacillus cereus, Clostridium perfringens, Salmonella, Clostridium botulinum, and Escherichia coli. Symptom onset times and clinical manifestations are provided for classifying different types of food poisoning. The document also covers food contamination and poisoning prevention methods.
Criteria for ideal indicators for pathogenic microorganisms in foodNada Sami
The document discusses criteria for ideal indicators of pathogenic microorganisms in food. It outlines that indicators should be of enteric origin and present in higher numbers than pathogens. It then examines various bacterial groups as potential indicators, including coliforms, fecal coliforms, E. coli, and enterococci. While no single indicator meets all criteria, these groups satisfy many as they are nonpathogenic and share habitats with foodborne pathogens. The document evaluates their ability to indicate fecal contamination and potential presence of pathogens in different foods.
Sauerkraut is a fermented cabbage product with a sour taste made through the lactic acid fermentation of shredded cabbage by lactic acid bacteria such as Leuconostoc mesenteroides and Lactobacillus plantarum. The fermentation process typically takes 4-8 weeks to produce sauerkraut with an acidity level of around 1.7% and beneficial probiotic bacteria. Sauerkraut is high in fiber, vitamins, and minerals and consumption has various health benefits such as supporting digestive health and reducing inflammation.
The document provides instructions for inoculating culture tubes and petri plates, performing serial dilutions, and preparing LB agar plates. It describes the steps for inoculating culture tubes which include flaming the tube mouth, placing the sterile inoculation loop in an active culture, transferring it to fresh media, and incubating. The steps for inoculating petri plates include covering 25% of the plate surface in a zig-zag pattern by rotating the plate. It defines serial dilutions as the stepwise dilution of a substance to manageably culture and isolate microorganisms. The preparation of LB agar includes weighing ingredients, adding them to water, boiling, and sterilizing the media to use as a non-selective growth substrate.
This document provides information on parasitic foodborne diseases. It discusses several protozoan parasites that can cause foodborne illness, including Toxoplasma gondii, Entamoeba histolytica, Giardia intestinalis. For each parasite, it describes their life cycle, transmission, symptoms, diagnosis and treatment. It notes that foodborne parasites are a major public health problem worldwide and can cause disease ranging from mild diarrhea to more severe complications in vulnerable groups. Prevention focuses on proper hygiene, sanitation and food handling practices.
The document discusses probiotics, their history, functions, and food sources. It begins by defining probiotics as live microorganisms that provide health benefits when consumed in adequate amounts. The concept of probiotics was first proposed in the early 20th century by Elie Metchnikoff, who suggested certain bacteria in fermented milk could promote intestinal and overall health. The document then outlines the characteristics, mechanisms of action, advantages, and functions of probiotic consumption before providing examples of probiotic foods and the probiotic strains they contain.
Food preservation methods aim to prevent microbial decomposition, self-decomposition, and damage from insects or animals. Key methods include preventing microbial growth through controlling factors like temperature, water activity, and pH. High temperatures can be used to pasteurize or sterilize foods through methods like canning. Drying and smoking also inhibit microbial growth by reducing water availability. Chemical preservatives interfere with microbial cell membranes and enzymes. Aseptic packaging, irradiation, low temperatures, and controlled atmospheres provide additional preservation techniques.
Foodborne diseases pose a significant threat to public health worldwide. They can be caused by bacteria, viruses, parasites or toxins entering the body through contaminated food. Major pathogens like Salmonella, E. coli and Campylobacter cause foodborne infections and intoxications with symptoms like diarrhea and vomiting. In developing countries, poor hygienic practices and lack of surveillance exacerbate the foodborne disease burden. Proper food safety practices and surveillance systems are needed to reduce illnesses and deaths from these preventable diseases.
This document discusses bacterial food poisoning, describing common causative agents, symptoms, pathogenesis, and methods of diagnosis. The major bacterial causes outlined are Staphylococcus aureus, Bacillus cereus, Clostridium perfringens, Salmonella, Clostridium botulinum, and Escherichia coli. Symptom onset times and clinical manifestations are provided for classifying different types of food poisoning. The document also covers food contamination and poisoning prevention methods.
Criteria for ideal indicators for pathogenic microorganisms in foodNada Sami
The document discusses criteria for ideal indicators of pathogenic microorganisms in food. It outlines that indicators should be of enteric origin and present in higher numbers than pathogens. It then examines various bacterial groups as potential indicators, including coliforms, fecal coliforms, E. coli, and enterococci. While no single indicator meets all criteria, these groups satisfy many as they are nonpathogenic and share habitats with foodborne pathogens. The document evaluates their ability to indicate fecal contamination and potential presence of pathogens in different foods.
Sauerkraut is a fermented cabbage product with a sour taste made through the lactic acid fermentation of shredded cabbage by lactic acid bacteria such as Leuconostoc mesenteroides and Lactobacillus plantarum. The fermentation process typically takes 4-8 weeks to produce sauerkraut with an acidity level of around 1.7% and beneficial probiotic bacteria. Sauerkraut is high in fiber, vitamins, and minerals and consumption has various health benefits such as supporting digestive health and reducing inflammation.
The document provides instructions for inoculating culture tubes and petri plates, performing serial dilutions, and preparing LB agar plates. It describes the steps for inoculating culture tubes which include flaming the tube mouth, placing the sterile inoculation loop in an active culture, transferring it to fresh media, and incubating. The steps for inoculating petri plates include covering 25% of the plate surface in a zig-zag pattern by rotating the plate. It defines serial dilutions as the stepwise dilution of a substance to manageably culture and isolate microorganisms. The preparation of LB agar includes weighing ingredients, adding them to water, boiling, and sterilizing the media to use as a non-selective growth substrate.
This document provides information on parasitic foodborne diseases. It discusses several protozoan parasites that can cause foodborne illness, including Toxoplasma gondii, Entamoeba histolytica, Giardia intestinalis. For each parasite, it describes their life cycle, transmission, symptoms, diagnosis and treatment. It notes that foodborne parasites are a major public health problem worldwide and can cause disease ranging from mild diarrhea to more severe complications in vulnerable groups. Prevention focuses on proper hygiene, sanitation and food handling practices.
The document discusses probiotics, their history, functions, and food sources. It begins by defining probiotics as live microorganisms that provide health benefits when consumed in adequate amounts. The concept of probiotics was first proposed in the early 20th century by Elie Metchnikoff, who suggested certain bacteria in fermented milk could promote intestinal and overall health. The document then outlines the characteristics, mechanisms of action, advantages, and functions of probiotic consumption before providing examples of probiotic foods and the probiotic strains they contain.
Food preservation methods aim to prevent microbial decomposition, self-decomposition, and damage from insects or animals. Key methods include preventing microbial growth through controlling factors like temperature, water activity, and pH. High temperatures can be used to pasteurize or sterilize foods through methods like canning. Drying and smoking also inhibit microbial growth by reducing water availability. Chemical preservatives interfere with microbial cell membranes and enzymes. Aseptic packaging, irradiation, low temperatures, and controlled atmospheres provide additional preservation techniques.
Detection techniques for microorganisms in food of animalMANJEET RATHOUR
The detection and enumeration of microorganisms in food are an essential
part of any quality control or food safety plan. Traditional methods of detecting foodborne pathogenic bacteria are often time-consuming because of the need for growth
in culture media, followed by isolation, biochemical and/or serological identifi cation,
and in some cases, subspecifi c characterization. Advances in technology have made
detection and identifi cation faster, more sensitive, more specifi c, and more convenient than traditional assays. These new methods include for the most part antibodyand DNA-based tests, and modifi cations of conventional tests made to speed up
analysis and reduce handling.
The document discusses the Most Probable Number (MPN) technique, which is used to estimate the concentration of viable microorganisms in water samples. It works by inoculating water samples into broth at different dilutions and observing growth, based on the principle of extinction dilution. A positive/negative result is obtained from lactose fermentation tests in broth. These results are interpreted using an MPN table to estimate the number of bacteria per 100ml of water. The document outlines the materials, presumptive test procedure involving broth incubation, confirmatory test using EMB agar plates, and complete test of Gram staining suspicious colonies to identify bacteria like E. coli.
The document discusses the history and development of medical microbiology from its earliest concepts to modern times. It describes key contributions from Antonie van Leeuwenhoek, who first observed microorganisms under a microscope; Louis Pasteur, considered the father of microbiology; Joseph Lister, the father of modern surgery; and Robert Koch, the father of bacteriology. It was during the 1800s that microbiology emerged as a scientific discipline, aided by advances like staining techniques, pure culture isolation, and Koch's postulates for identifying microbes that cause disease. The early 1900s marked the discovery of viruses and antibiotics like penicillin. Overall, the document provides a comprehensive overview of the scientific milestones that established microbiology
Bacillus cereus is a rod-shaped, Gram-positive, spore-forming bacterium commonly found in soil and foods. It can cause two types of food poisoning - a diarrheal syndrome caused by enterotoxins and an emetic syndrome caused by a preformed toxin. B. cereus grows between 4-55°C and pH 4.5-9.5, producing spores that allow it to survive harsh conditions. While usually a mild foodborne illness, prevention focuses on proper cooking and refrigeration to limit growth and toxin production in foods.
COLLECTION AND TRANSPORTATION OF CLINICAL SAMPLESNCRIMS, Meerut
Principles of Sample Collection:
Aseptic precautions to minimize chances of
contamination.
Appropriate anatomic sites
Adequate volume
Adequate no. of samples
Appropriate time
Appropriate container with proper labelling
Before initiation of anti-microbials
Adequate information in request form
This document describes various methods for isolating and identifying bacteria, including:
1) Isolating pure colonies through streak plating and noting colony characteristics. Pure cultures are obtained through transfer to agar slants.
2) Gram staining, which differentiates bacteria as gram positive or negative based on cell wall structure.
3) Biochemical tests including IMViC (Indole, Methyl Red, Voges Proskauer, Citrate) which identify enteric bacteria based on fermentation patterns.
4) Additional tests like triple sugar iron, urease, and sugar fermentation patterns provide further differentiation of bacteria.
Salmonella is a genus of bacteria that can cause infections in humans and other animals. There are over 2000 serotypes of Salmonella, with some causing typhoid fever and paratyphoid fever through consumption of contaminated food or water. S. Typhi specifically causes typhoid fever, a systemic illness involving the gastrointestinal tract and bloodstream. The disease progresses as the bacteria penetrate the intestines, spread to internal organs, and multiply before reentering the bloodstream and causing symptoms like sustained fever and abdominal pain. Carriers of S. Typhi pose a public health risk by potentially spreading the infection through food preparation.
Foodborne diseases are caused by consuming contaminated food or drink. Over 250 foodborne diseases have been described, mostly caused by bacteria, viruses and parasites. The most common foodborne diseases are caused by Campylobacter, Salmonella, E. coli O157:H7, and noroviruses. Raw foods of animal origin pose the highest risk of contamination. Proper cooking and cleaning can help prevent foodborne illnesses. Thorough investigation is needed to identify the contaminated source during outbreaks to prevent future illnesses.
Sauerkraut is finely cut cabbage that is fermented by various lactic acid bacteria, including Leuconostoc mesenteroides, Lactobacillus plantarum, and Lactobacillus pentoaceticus. The fermentation process sour's the cabbage and gives it a long shelf life. Sauerkraut is recommended for treatment of overweight, metabolic disorders, and detoxification. To make sauerkraut, shredded cabbage is packed in a container with salt added which draws out juice for microbial fermentation. Proper temperature, salt levels, and starter cultures are needed to ensure consistent high quality fermentation.
The document discusses methods for examining food and water microbiologically. There are three main methods discussed: culture media methods, immunoassay methods, and polymerase chain reaction (PCR) methods. Culture media methods involve culturing samples on selective and differential media to isolate and identify microorganisms. Immunoassay methods like ELISA use antigen-antibody binding to detect toxins and microbes. PCR methods amplify and detect targeted nucleic acid sequences to identify pathogens. Examining food and water microbiologically is important to ensure safety and determine processing parameters needed to meet standards.
Nutritional requirement by microorganismsSuchittaU
Nutrients are required for microbial growth and act as building blocks and energy sources. The main nutrient requirements for microorganisms include carbon, nitrogen, phosphorus, sulfur, hydrogen, oxygen, potassium, calcium, magnesium, iron and trace elements. Microorganisms can be classified based on their carbon, energy and electron sources as photolithotrophs, photoorganoheterotrophs, chemolithoautotrophs, chemolithoheterotrophs or chemoorganoheterotrophs. Culture media are used to grow microorganisms and include defined, complex, liquid, solid, supportive, enriched, selective and differential media depending on their composition and purpose.
The document describes several methods for enumerating and identifying microorganisms in foods:
1) Total plate count, coliform test, and tests for mesophilic bacteria, staphylococci, and pathogenic bacteria like Salmonella and Shigella are discussed.
2) Culture-based techniques like streak plating, spread plating, and pour plating on agar plates are used to determine microbial numbers.
3) The coliform test involves presumptive, confirmation, and completed stages to identify coliform bacteria. Testing for specific microorganisms like Salmonella involves enrichment and plating followed by screening and confirmation tests.
Microbial spoilage of meat & meat products9404577899
This document discusses contamination, preservation, and spoilage of meat and meat products. It notes that the main sources of contamination are during slaughtering, handling, and processing when microorganisms can be introduced from surfaces, air, clothing, and equipment that contact the meat. Common preservation methods described are use of heat (canning, smoking), low temperatures (chilling, freezing), irradiation, drying, use of preservatives like curing agents, smoking, and spices, and antibiotics. Spoilage occurs through the action of meat enzymes and microbes that invade the tissues, with factors like the animal's gut load and stress level before slaughter impacting the degree of invasion.
The document discusses foodborne infections and intoxications. Foodborne infections occur when harmful microorganisms in contaminated food grow in the intestines and cause illness, while intoxications result from toxins produced by microorganisms or present in plants/seafood. Common bacteria that can cause infections include Salmonella, Listeria, Campylobacter, and viruses like Hepatitis A and parasites such as Giardia. Symptoms include diarrhea and vomiting. Prevention methods include proper food handling and cooking practices.
Cereals and cereal products are susceptible to contamination and spoilage by microorganisms if not properly stored. Moisture content above 13% allows mold and bacterial growth. Common spoilage microorganisms include various bacteria and mold species. Proper preservation methods include low storage temperatures below 7°C, use of preservatives like propionates, and irradiation to reduce microbes. Mold growth is a major cause of bread spoilage and can be prevented through proper cooling, low humidity storage, and surface treatments. Ropiness of bread is caused by Bacillus species surviving baking and growing if conditions are favorable.
This document provides information about microorganisms and their classification. It discusses that microorganisms are very small organisms that cannot be seen with the naked eye, including bacteria, fungi, protozoa, algae, and viruses. It also describes the prokaryotic and eukaryotic cell structures, and explains how microorganisms are classified based on their shape, staining properties, nutritional requirements, temperature and pH tolerances, and oxygen requirements. The document highlights different types of microbial reproduction including binary fission.
The document discusses food microbiology and methods for detecting microbes in food. It describes how microorganisms are introduced to foods and both their beneficial roles in fermentation and spoilage when conditions allow undesirable growth. Detection methods discussed include plate counts, membrane filtration, and microscopic analysis. Intrinsic food factors like pH, water activity, and natural antimicrobials and extrinsic storage conditions like temperature and atmosphere that influence microbial growth are also summarized.
The document discusses factors that affect microbial growth in foods. It describes the microbial growth curve and identifies four main factors that influence growth: intrinsic properties of the food itself, extrinsic environmental conditions, implicit properties of microorganisms, and processing factors. Specific intrinsic factors discussed include nutrients, pH, water activity, and antimicrobial constituents. Extrinsic factors include temperature, relative humidity, and atmospheric gases. Implicit factors include microbial interactions like mutualism and antagonism.
Bacillus anthracis is a gram-positive, spore-forming bacterium that causes the disease anthrax. It forms spores that allow it to survive in the environment for decades. Anthrax infection can occur through the skin, lungs, or gastrointestinal tract. Symptoms and signs depend on the route of infection but may include lesions, fever, vomiting, shock, and death. Diagnosis involves culture, PCR, or antigen detection. Penicillin is the treatment of choice but vaccination is also used to prevent infection. Due to its ability to be easily weaponized, B. anthracis is considered a category A bioterrorism agent.
Clinical chemistry review sheet for mlt certification and ascpDonna Kim
This is a fairly thorough without being bogged down with unnecessary detail study guide for Medical Laboratory Technician studying for the review and state exams
Acid Base
Carbohydrates
Lipids
Proteins
Amino Acids
Staphylococcus and Streptococcus are important gram-positive bacteria. Staphylococcus includes pathogens like S. aureus and S. epidermidis. S. aureus causes skin infections like boils and toxic shock syndrome. S. epidermidis causes UTIs and endocarditis. Streptococcus includes S. pyogenes, S. agalactiae, and S. pneumoniae. S. pyogenes causes strep throat and rheumatic fever. S. agalactiae causes infections in newborns. S. pneumoniae causes pneumonia and ear infections. Identification involves tests like catalase, coagulase, and hemolytic properties on blood agar. Antibiotics like pen
Detection techniques for microorganisms in food of animalMANJEET RATHOUR
The detection and enumeration of microorganisms in food are an essential
part of any quality control or food safety plan. Traditional methods of detecting foodborne pathogenic bacteria are often time-consuming because of the need for growth
in culture media, followed by isolation, biochemical and/or serological identifi cation,
and in some cases, subspecifi c characterization. Advances in technology have made
detection and identifi cation faster, more sensitive, more specifi c, and more convenient than traditional assays. These new methods include for the most part antibodyand DNA-based tests, and modifi cations of conventional tests made to speed up
analysis and reduce handling.
The document discusses the Most Probable Number (MPN) technique, which is used to estimate the concentration of viable microorganisms in water samples. It works by inoculating water samples into broth at different dilutions and observing growth, based on the principle of extinction dilution. A positive/negative result is obtained from lactose fermentation tests in broth. These results are interpreted using an MPN table to estimate the number of bacteria per 100ml of water. The document outlines the materials, presumptive test procedure involving broth incubation, confirmatory test using EMB agar plates, and complete test of Gram staining suspicious colonies to identify bacteria like E. coli.
The document discusses the history and development of medical microbiology from its earliest concepts to modern times. It describes key contributions from Antonie van Leeuwenhoek, who first observed microorganisms under a microscope; Louis Pasteur, considered the father of microbiology; Joseph Lister, the father of modern surgery; and Robert Koch, the father of bacteriology. It was during the 1800s that microbiology emerged as a scientific discipline, aided by advances like staining techniques, pure culture isolation, and Koch's postulates for identifying microbes that cause disease. The early 1900s marked the discovery of viruses and antibiotics like penicillin. Overall, the document provides a comprehensive overview of the scientific milestones that established microbiology
Bacillus cereus is a rod-shaped, Gram-positive, spore-forming bacterium commonly found in soil and foods. It can cause two types of food poisoning - a diarrheal syndrome caused by enterotoxins and an emetic syndrome caused by a preformed toxin. B. cereus grows between 4-55°C and pH 4.5-9.5, producing spores that allow it to survive harsh conditions. While usually a mild foodborne illness, prevention focuses on proper cooking and refrigeration to limit growth and toxin production in foods.
COLLECTION AND TRANSPORTATION OF CLINICAL SAMPLESNCRIMS, Meerut
Principles of Sample Collection:
Aseptic precautions to minimize chances of
contamination.
Appropriate anatomic sites
Adequate volume
Adequate no. of samples
Appropriate time
Appropriate container with proper labelling
Before initiation of anti-microbials
Adequate information in request form
This document describes various methods for isolating and identifying bacteria, including:
1) Isolating pure colonies through streak plating and noting colony characteristics. Pure cultures are obtained through transfer to agar slants.
2) Gram staining, which differentiates bacteria as gram positive or negative based on cell wall structure.
3) Biochemical tests including IMViC (Indole, Methyl Red, Voges Proskauer, Citrate) which identify enteric bacteria based on fermentation patterns.
4) Additional tests like triple sugar iron, urease, and sugar fermentation patterns provide further differentiation of bacteria.
Salmonella is a genus of bacteria that can cause infections in humans and other animals. There are over 2000 serotypes of Salmonella, with some causing typhoid fever and paratyphoid fever through consumption of contaminated food or water. S. Typhi specifically causes typhoid fever, a systemic illness involving the gastrointestinal tract and bloodstream. The disease progresses as the bacteria penetrate the intestines, spread to internal organs, and multiply before reentering the bloodstream and causing symptoms like sustained fever and abdominal pain. Carriers of S. Typhi pose a public health risk by potentially spreading the infection through food preparation.
Foodborne diseases are caused by consuming contaminated food or drink. Over 250 foodborne diseases have been described, mostly caused by bacteria, viruses and parasites. The most common foodborne diseases are caused by Campylobacter, Salmonella, E. coli O157:H7, and noroviruses. Raw foods of animal origin pose the highest risk of contamination. Proper cooking and cleaning can help prevent foodborne illnesses. Thorough investigation is needed to identify the contaminated source during outbreaks to prevent future illnesses.
Sauerkraut is finely cut cabbage that is fermented by various lactic acid bacteria, including Leuconostoc mesenteroides, Lactobacillus plantarum, and Lactobacillus pentoaceticus. The fermentation process sour's the cabbage and gives it a long shelf life. Sauerkraut is recommended for treatment of overweight, metabolic disorders, and detoxification. To make sauerkraut, shredded cabbage is packed in a container with salt added which draws out juice for microbial fermentation. Proper temperature, salt levels, and starter cultures are needed to ensure consistent high quality fermentation.
The document discusses methods for examining food and water microbiologically. There are three main methods discussed: culture media methods, immunoassay methods, and polymerase chain reaction (PCR) methods. Culture media methods involve culturing samples on selective and differential media to isolate and identify microorganisms. Immunoassay methods like ELISA use antigen-antibody binding to detect toxins and microbes. PCR methods amplify and detect targeted nucleic acid sequences to identify pathogens. Examining food and water microbiologically is important to ensure safety and determine processing parameters needed to meet standards.
Nutritional requirement by microorganismsSuchittaU
Nutrients are required for microbial growth and act as building blocks and energy sources. The main nutrient requirements for microorganisms include carbon, nitrogen, phosphorus, sulfur, hydrogen, oxygen, potassium, calcium, magnesium, iron and trace elements. Microorganisms can be classified based on their carbon, energy and electron sources as photolithotrophs, photoorganoheterotrophs, chemolithoautotrophs, chemolithoheterotrophs or chemoorganoheterotrophs. Culture media are used to grow microorganisms and include defined, complex, liquid, solid, supportive, enriched, selective and differential media depending on their composition and purpose.
The document describes several methods for enumerating and identifying microorganisms in foods:
1) Total plate count, coliform test, and tests for mesophilic bacteria, staphylococci, and pathogenic bacteria like Salmonella and Shigella are discussed.
2) Culture-based techniques like streak plating, spread plating, and pour plating on agar plates are used to determine microbial numbers.
3) The coliform test involves presumptive, confirmation, and completed stages to identify coliform bacteria. Testing for specific microorganisms like Salmonella involves enrichment and plating followed by screening and confirmation tests.
Microbial spoilage of meat & meat products9404577899
This document discusses contamination, preservation, and spoilage of meat and meat products. It notes that the main sources of contamination are during slaughtering, handling, and processing when microorganisms can be introduced from surfaces, air, clothing, and equipment that contact the meat. Common preservation methods described are use of heat (canning, smoking), low temperatures (chilling, freezing), irradiation, drying, use of preservatives like curing agents, smoking, and spices, and antibiotics. Spoilage occurs through the action of meat enzymes and microbes that invade the tissues, with factors like the animal's gut load and stress level before slaughter impacting the degree of invasion.
The document discusses foodborne infections and intoxications. Foodborne infections occur when harmful microorganisms in contaminated food grow in the intestines and cause illness, while intoxications result from toxins produced by microorganisms or present in plants/seafood. Common bacteria that can cause infections include Salmonella, Listeria, Campylobacter, and viruses like Hepatitis A and parasites such as Giardia. Symptoms include diarrhea and vomiting. Prevention methods include proper food handling and cooking practices.
Cereals and cereal products are susceptible to contamination and spoilage by microorganisms if not properly stored. Moisture content above 13% allows mold and bacterial growth. Common spoilage microorganisms include various bacteria and mold species. Proper preservation methods include low storage temperatures below 7°C, use of preservatives like propionates, and irradiation to reduce microbes. Mold growth is a major cause of bread spoilage and can be prevented through proper cooling, low humidity storage, and surface treatments. Ropiness of bread is caused by Bacillus species surviving baking and growing if conditions are favorable.
This document provides information about microorganisms and their classification. It discusses that microorganisms are very small organisms that cannot be seen with the naked eye, including bacteria, fungi, protozoa, algae, and viruses. It also describes the prokaryotic and eukaryotic cell structures, and explains how microorganisms are classified based on their shape, staining properties, nutritional requirements, temperature and pH tolerances, and oxygen requirements. The document highlights different types of microbial reproduction including binary fission.
The document discusses food microbiology and methods for detecting microbes in food. It describes how microorganisms are introduced to foods and both their beneficial roles in fermentation and spoilage when conditions allow undesirable growth. Detection methods discussed include plate counts, membrane filtration, and microscopic analysis. Intrinsic food factors like pH, water activity, and natural antimicrobials and extrinsic storage conditions like temperature and atmosphere that influence microbial growth are also summarized.
The document discusses factors that affect microbial growth in foods. It describes the microbial growth curve and identifies four main factors that influence growth: intrinsic properties of the food itself, extrinsic environmental conditions, implicit properties of microorganisms, and processing factors. Specific intrinsic factors discussed include nutrients, pH, water activity, and antimicrobial constituents. Extrinsic factors include temperature, relative humidity, and atmospheric gases. Implicit factors include microbial interactions like mutualism and antagonism.
Bacillus anthracis is a gram-positive, spore-forming bacterium that causes the disease anthrax. It forms spores that allow it to survive in the environment for decades. Anthrax infection can occur through the skin, lungs, or gastrointestinal tract. Symptoms and signs depend on the route of infection but may include lesions, fever, vomiting, shock, and death. Diagnosis involves culture, PCR, or antigen detection. Penicillin is the treatment of choice but vaccination is also used to prevent infection. Due to its ability to be easily weaponized, B. anthracis is considered a category A bioterrorism agent.
Clinical chemistry review sheet for mlt certification and ascpDonna Kim
This is a fairly thorough without being bogged down with unnecessary detail study guide for Medical Laboratory Technician studying for the review and state exams
Acid Base
Carbohydrates
Lipids
Proteins
Amino Acids
Staphylococcus and Streptococcus are important gram-positive bacteria. Staphylococcus includes pathogens like S. aureus and S. epidermidis. S. aureus causes skin infections like boils and toxic shock syndrome. S. epidermidis causes UTIs and endocarditis. Streptococcus includes S. pyogenes, S. agalactiae, and S. pneumoniae. S. pyogenes causes strep throat and rheumatic fever. S. agalactiae causes infections in newborns. S. pneumoniae causes pneumonia and ear infections. Identification involves tests like catalase, coagulase, and hemolytic properties on blood agar. Antibiotics like pen
Medical Laboratory Scientist-microbiology summaryProtegeNithi
This document summarizes microbiology concepts and tests for the ASCP medical laboratory scientist exam, including morphology of bacteria, staining techniques like Gram stain and acid-fast stain, characteristics of gram-positive and gram-negative bacteria, and the triple sugar iron agar test used to identify enteric bacteria. It provides examples and interpretations of triple sugar iron agar test results.
1. must to know in clinical chemistry 001Nhil Abaya
1. Quality control in clinical chemistry involves daily monitoring of accuracy and precision through intralaboratory and interlaboratory quality control to ensure reliability and practicability of methods.
2. Common sources of error in clinical chemistry methods include matrix effects from improper product manufacturing, imprecision caused by pre-analytical variables like mislabeling or pipetting errors, and inaccuracy from analytical variables like deterioration of reagents or contaminated solutions.
3. Proper patient preparation is important to obtain accurate results, as activities like exercise, diet, posture, or medical conditions can influence analyte levels by altering hemoconcentration, metabolism, or other physiological factors.
Compilation of previous board examination questionsRhem Rick Corpuz
This document provides guidance for test preparation and test-taking strategies. It recommends the following:
1) Review materials 3 months in advance by reading books and notes individually and creating a schedule.
2) Visit the exam center beforehand and choose a good seating position. Relax the day before by sleeping early and avoiding stress.
3) During the exam, stay relaxed and focused. Read questions fully before answering and use logic to eliminate incorrect options. Leave blank questions if running short on time.
4) For multiple choice questions, identify keywords in the stem and associate answers with them. Eliminate irrelevant options using logic.
The document discusses the purpose and functions of clinical pathology and laboratory medicine in assisting clinicians. It outlines five main ways laboratories help clinicians, including confirming or rejecting diagnoses, providing guidance in patient management, establishing prognoses, detecting diseases through screening and case finding, and monitoring therapy. It also discusses the scope and role of clinical chemistry, various laboratory tests, types of specimens, substances measured, and factors that can cause cell malfunctions.
1. Infections are caused by the invasion and multiplication of microbes in body tissues, which may result in local cellular injury or clinically apparent infectious disease.
2. Infections can be classified based on their occurrence, source, clinical effects, and how they spread. Common sources of infection include human beings, insects, animals, soil, water, and food.
3. The pathogenicity and virulence of microbes are determined by their ability to adhere, invade tissues, produce toxins, and spread from person to person.
This document is a resume for M'Lissa Kurtz, seeking a position as a lab technician or research associate. Kurtz has experience in diagnostic testing including hematology, urinalysis, coagulation, serology, immunology and microbiology. She is proficient in laboratory techniques such as complete blood counts, urinalysis, bacterial culture, ELISA and Latex Agglutination testing. Kurtz is also experienced with laboratory analyzers, quality control, safety procedures and computer systems. She holds an Associate's degree in Medical Laboratory Technician and is licensed and certified as an MLT in California.
AVATA Webinar: Upgrading ASCP - The New Face of ASCP is Here! www.avata.comAVATA
The document summarizes key enhancements across various releases of Oracle Advanced Supply Chain Planning (ASCP). Some highlights include:
- Release 12.1.1 included features like forecast spreading based on shipping calendars and end item substitution.
- Release 12.2 introduced premium resource capacity constraints and warehouse capacity constraints to better model complex supply chains.
- The most recent release 12.2.5.1 features a new "Alta" graphical user interface and capabilities like maximum resource utilization.
- Other upgrades focused on improved minimum remaining shelf life handling, purchase order consumption, integration with maintenance planning, and more flexible reporting and data exports.
This document provides lecture notes on hematology. It discusses the composition of blood, including plasma, red blood cells, white blood cells and platelets. It describes the functions of blood in transportation, regulation and protection. It also outlines the process of hemopoiesis or formation of blood cells from stem cells in the bone marrow, and the regulatory mechanisms that control blood cell production.
This document provides definitions and information about infectious diseases. It begins by defining infection as the invasion of a host's tissues by microorganisms that can cause subsequent injury and disease. An infectious disease is caused by the presence of microorganisms. Pathogenicity refers to a microbe's ability to cause disease, while virulence refers to the degree of pathogenicity. The document then discusses various microorganisms that can cause infections like viruses, bacteria, fungi, and parasites. It also covers the basic principles of infection transmission, prevention, and the nature of microorganisms. The stages of infectious disease are described along with factors that influence pathogenicity.
This document discusses biosafety levels (BSL) for handling pathogens in laboratories and provides examples of pathogens for each level. It also summarizes categories of public health threats (A, B, C), key indicators of potential bioterrorism, characteristics of bioterror agents, examples of criminal use of microbes, and the structure and function of the Laboratory Response Network for handling bioterrorism cases in the US. It provides overviews of several pathogenic bacteria and viruses of concern for bioterrorism, including anthrax, plague, tularemia, brucellosis, and viral hemorrhagic fevers.
This document discusses pathogenicity and virulence of microbes. It defines key terms like pathogenicity, infectiousness, infection, disease, and discusses the relationship between microbes and their hosts. It describes different types of pathogens like primary/obligate and opportunistic pathogens. It also discusses factors that determine pathogenicity like the microbial species, host species, and environment. It provides examples of opportunistic pathogens like E. coli and S. aureus. It defines virulence and attenuation, using the example of the BCG vaccine.
A woman had an anaphylactic reaction during a blood transfusion minutes after it started, with symptoms of flushing, chest tightness and difficulty breathing. Epinephrine was administered with good effect. The most likely cause was the woman being IgA-deficient and having antibodies against IgA in the donor blood.
A woman developed a fever and jaundice after a blood transfusion during surgery. Her hemoglobin had dropped unexpectedly. The most likely cause was recipient antibodies against donor red blood cell antigens not detected on the pre-transfusion testing, causing a delayed hemolytic reaction.
A man receiving a blood transfusion developed a fever within 15 minutes. Tests found no evidence of hemolysis.
This document provides an overview of the schedule and topics for a course on metabolic networks. The course covers various topics related to metabolism, including enzyme assays, mass spectrometry techniques, primary metabolism, glycogen metabolism, metabolic networks in humans, flux analysis, and biochemical databases. Homework discussions are scheduled every other Friday. Guest lecturers will discuss biochemical databases and tools for modeling metabolism on the last two class meetings. The course includes no class on Veteran's Day and Thanksgiving.
Instrumental techniques available for use in enzymatic analysisAfzal Farooque
This document discusses various instrumental techniques that can be used for enzymatic analysis, including manometry, spectrophotometry, spectrofluorimetry, electrochemical methods, enthalpimetry, radiochemical methods, and dry-reagent techniques. It also covers automation in enzymatic analysis and high-throughput assays. Some key techniques mentioned are manometry to monitor reactions involving gases, spectrophotometry using the Beer-Lambert law to follow reactions involving NADH/NADPH, and radiochemical methods using radioactively labeled substrates to measure product formation over time. Fully automated procedures allow simultaneous analysis of multiple samples without manual intervention between steps.
This document is a PowerPoint presentation on microbial growth. It discusses the physical, chemical, and environmental requirements for microbial growth, including temperature, pH, osmotic pressure, nutrients, and oxygen levels. It also covers topics like biofilm formation, culture media, obtaining pure cultures, and preserving bacterial cultures. The key growth phases of bacteria, including binary fission, are explained. Methods for isolating and culturing microbes under different conditions are presented.
Laboratory method for measuring enzyme activity.
Vital for study of enzyme kinetics and enzyme inhibition.
Measurement of enzyme activity – follow the change in concentration of substrate or product – measure reaction rate.
The document discusses several clinical chemistry tests including glucose, proteins, and lipids. It provides details on glucose determination methods, normal and abnormal glucose levels, and potential causes of hyperglycemia and hypoglycemia. It also outlines the main functions and assessments of various plasma proteins, including total protein, albumin, and globulins that are separated via electrophoresis.
WHAT IS SPOILAGE? • Spoilage is the process in which food deteriorates to the point in which it is not edible to humans or its quality of edibility becomes reduced OR • Any change which renders a product unacceptable for human consumption. • Complex event in which a combination of microbial and biochemical activities may interact. • One of the major reason that led to preservation.
FACTORS DETERMINING THE SPOILAGE • Microbial colonization depends on – characteristics of product – The way processed – The way stored • Factors are characterized into four: – Intrinsic parameters – Extrinsic parameters – Modes of preservation and processing – Implicit parameters
INTRINSIC PARAMETERS • Physical, chemical and structural properties. • Inherent in the food itself. • Important factors include water activity, acidity, redox potential, available nutrients and natural antimicrobial substances. EXTRINSIC PARAMETERS • Factors in the environment where food is stored • Temperature, humidity and atmosphere conditions.
MODES OF PRESERVATION AND PROCESSING • Physical or chemical treatment • Change characteristics of food product • Determine the micro flora associated with the product IMPLICIT PARAMETERS OR MICROBIAL INTERFERENCE • These are the result of the development of synergistic or antagonistic microbes • It can be said as the destruction of one organism by another species releasing H2 O2 , bacteriocin and other di-acetyl compounds.
• Synergistic: Production or availability of essential nutrients due to the growth of certain organisms, which allow the growth of another group which were otherwise unable to grow. • Antagonistic : Competition for essential nutrients, changes in pH value or redox potential or formation of antimicrobial substances.
TYPES OF SPOILAGE Two types of Spoilage: • Microbial spoilage • Non- Microbial Based on rate of spoilage: • Highly perishable – Meat, fish, poultry, eggs, milk, most fruits and vegetables. • Semi perishable – Potatoes, some apple varieties, nutmeats • Stable or non-perishable – Sugar, flour, dry beans
SPOILAGE OF FRUITS AND VEGETABLES • The organism responsible for taints are acid tolerant bacteria: – Lactobacillus spp. • Deterioration can be caused by action of animals, birds, bruising, wounding, cutting, freezing, dessication or other mishandling and growth of microorganisms; environmental conditions, contact with spoiled foods. • Microbial spoilage maybe due to: – Plant pathogens acting on stems, leaves, flowers or roots – Saprophytic organisms
• Types of spoilages: – Bacterial soft rot • Caused by Erwinia carotovora, ferment pectins • Pseudomonas marginalis, Bacillus and Clostridium cause water soaked appearance, a soft, mushy consistency and bad odour. – Anthracnose • Caused by Collectotrichum lindemuthianum. • Spotting of leaves and fruits – Black mold rot • Caused by Aspergillus niger • Dark brown to black masses of spores of the mold termed as smut
• Rhizopus soft rot – Caused by species of Rhizopus – Soft and mu
Food microbiology is the study of microorganisms that are present in foods and can affect food quality and safety. Microbes can be beneficial, neutral, or harmful to humans. Foods provide excellent nutrients to support microbial growth. There are many factors that affect microbial growth in foods, including intrinsic factors like pH, moisture content, and nutrients as well as extrinsic factors like temperature, relative humidity, gases, and time. Microbial spoilage of foods is evidenced by changes in appearance, texture, odor, and flavor and is caused by bacteria, molds, and yeasts growing in the food.
The document discusses various factors that influence the growth and activity of microorganisms in food. Internally, key factors include nutrient contents, water activity, pH, redox potential, and osmotic pressure. Externally, temperature is a major influence on microbial growth rates, with psychrophiles, mesophiles, and thermophiles having different optimal temperature ranges. The heat resistance of microorganisms is also affected by time, temperature, microbial type, number, pH, water content, and food composition. Controlling these internal and external factors is important for preventing microbial spoilage of foods.
The document discusses various factors that influence the growth and activity of microorganisms in food. Internally, key factors include nutrient contents, water activity, pH, redox potential, and osmotic pressure. Externally, temperature is a major influence on microbial growth rates, with psychrophiles, mesophiles, and thermophiles having different optimal temperature ranges. The document also discusses how these various factors affect the heat resistance of microorganisms.
This document provides an overview of the history of food microbiology and the key factors that influence microbial growth in foods. It discusses how microorganisms interact with foods, using them as a nutrient source and potentially spoiling the food. The major factors described are pH, moisture as measured by water activity, nutrients present in the food, inhibitory substances, temperature, gas concentration in the storage environment, and relative humidity. Optimal ranges for growth are defined for different types of microbes under each factor.
Food spoilage is caused by the growth of microorganisms like bacteria, yeasts, and molds. Several factors influence microbial growth in food, including temperature, pH, moisture content, and nutrient levels. Food preservation techniques aim to inhibit microbial growth through methods like reducing water activity by drying and salting foods or lowering the pH. Proper control of factors like temperature, gases, and humidity during food storage is important for limiting spoilage.
Microorganisms can cause food deterioration by utilizing nutrients in food and producing enzymatic changes or new compounds that cause spoiling. To prevent spoilage, contact between microorganisms and food must be minimized by eliminating microorganisms from foods and understanding food preservation methods. Microorganisms are found in many places including soil, water, plants, equipment, food handlers, and air. They can be beneficial by aiding fermentation or pathogenic by causing foodborne illness or spoilage. Factors like pH, water activity, nutrients, and temperature affect microbial behavior in food.
Food spoilage is caused by the growth of microorganisms like bacteria, yeasts, and molds. Several factors influence microbial growth in food, including pH, moisture content, temperature, gas concentration, and relative humidity. Food preservation techniques aim to inhibit microbial growth through methods like reducing water activity by drying and salting foods or lowering the pH through fermentation. This prevents food from being damaged or contaminated, rendering it unsuitable for human consumption.
This document discusses food microbiology. It explains that food contains microorganisms that can either cause deterioration through spoilage or interact beneficially. Microorganisms use foods as a nutrient source. They can spoil food through synthesis of new compounds or enzymatic breakdown. However, some microorganisms are used in food processing like fermentation or as probiotics. Factors like pH, moisture, nutrients, and temperature influence microbial growth in foods.
This document discusses food microbiology and food spoilage. It begins by introducing food storage and factors that contribute to food deterioration like microorganism growth. The major causes of food spoilage are microbial growth, enzymatic reactions, chemical reactions, vermin, and physical changes. Specific microorganisms like bacteria, yeasts and molds are responsible for food spoilage. Factors like temperature, pH, moisture content and nutrients influence microbial growth in food. Food preservation techniques aim to prolong food storage life by preventing microbial spoilage.
Factors affecting the growth of microorganisms in food food miDiljeetMaan
The growth of microorganisms in food depends on various intrinsic, extrinsic, and implicit factors. Intrinsic factors include the pH, water activity, oxidation-reduction potential, and nutrient content of the food itself. Extrinsic factors refer to the storage temperature, relative humidity, and atmospheric gases the food is exposed to. Implicit factors relate to microbial interactions between different organisms. The document discusses the ranges of these various factors that allow or inhibit the growth of different types of bacteria, yeasts and molds. Food processing methods can also affect microbes through physical or chemical stresses like heating, freezing, drying and chemical treatments.
Bsc food technology
Second semester
Food microbiology
Notes
Third unit
Contamination and spoilage of food
Factors influencing the growth of micro organisms in food
1) Many factors influence the growth and heat resistance of microorganisms in food, including temperature, pH, water activity, redox potential, nutrient levels, and number of microorganisms present.
2) The optimal temperature, pH, and water activity levels vary between bacterial species, with psychrotrophs growing at refrigeration temperatures and thermophiles growing at higher temperatures.
3) Higher numbers of microorganisms, pH levels closer to optimal, and more water or fat content can increase heat resistance by providing a protective environment.
1) Bacteria and fungi are the most common microbial growths in food, with bacteria being the primary cause of food poisoning. 2) The main factors influencing microbial growth are: food/nutrients, acidity, time, temperature, oxygen, and moisture. Bacteria need adequate levels of these factors, known as "FAT TOM", to multiply. 3) Various food preservation techniques control these factors, such as reducing water availability through drying, salting, or sugar preservation, or depriving microbes of oxygen through canning or vacuum sealing.
1. The document provides an introduction to food microbiology, discussing factors that influence food spoilage such as microorganism growth, pH, moisture content, and temperature.
2. It describes various food preservation methods including inhibiting microorganism growth through reducing water activity via drying or salting, or lowering pH with fermentation or acids.
3. The document also discusses killing microorganisms using heat treatments like pasteurization or sterilization, irradiation, or gases. Combining inhibition and killing principles is often used in food preservation depending on the food.
Factors that affect microbial growth by Pranzly.pptxPranzly Rajput
Intrinsic and extrinsic factors
Intrinsic factors include
Characteristics of the food itself are called intrinsic factors.
These include naturally occurring compounds that influence microbial growth,
MOISTURE CONTENT
pH AND ACIDITY
NUTRIENT CONTENT
BIOLOGICAL STRUCTURE
REDOX POTENTIAL
NATURALLY OCCURING AND ADDED ANTIMICROBIAL
Extrinsic factors are those that refer to the environment surrounding the food.
TYPES OF PACKAGING AND ATMOSPHERES
EFFECT OF TIME/TEMPERATURE CONDITIONS ON MICROBIAL GROWTH
STORAGE AND HOLDING CONDITION
PROCESSING STEPS
This document discusses factors that influence microbial growth in food. It outlines intrinsic factors like pH, water activity, nutrients, and antimicrobial substances; as well as extrinsic factors such as temperature, gas concentration, and humidity. Specific microorganisms are detailed that grow within certain pH ranges, water activity levels, temperature ranges like psychrophiles at below 20°C and thermophiles above 45°C. The document also provides examples of how these various factors impact microbial growth in different foods.
Factors affecting microbial growth in Livestock productsRavi Kant Agrawal
This document discusses various intrinsic and extrinsic factors that affect microbial growth in livestock products. Intrinsic factors include biological structures, nutrients, water activity, pH, redox potential, and antimicrobial constituents present in the food. Extrinsic factors include temperature, relative humidity, and gaseous environment during storage. The growth and survival of microorganisms depends on whether the conditions meet their requirements for things like pH range, temperature optimum, oxygen needs, and available nutrients. Controlling these factors can help prevent undesirable microbial growth in foods.
Similar to Microbiology Q & A for exam (short note) (20)
This document presents the baseline survey report on the Value Chain Development project under PACE being implemented by SNF and PKSF in Mohespur Upazila, Jhinaidah District. The objective is to collect baseline data on the Imitation Gold Jewelry sector to measure changes from project interventions. A sample size of 246 entrepreneurs was surveyed using systematic sampling from the 600 project beneficiaries. Both quantitative and qualitative methods were used, including questionnaires, FGDs, IDIs and KIIs. The report provides background on the project, methodology, findings on the current status of the IGJ sector value chain actors, inputs, production, markets and recommendations.
This document provides a summary of the baseline survey conducted for the PACE project implemented by GJUS in Bhola, Bangladesh. The survey aimed to collect benchmark data on the aromatic rice and mungbean value chains in 5 upazilas to measure changes from project interventions. A sample of 404 farmers was selected through systematic sampling from a population of 8,000 project beneficiaries. Quantitative and qualitative methods including questionnaires, FGDs, and interviews were used. The collected data will help assess the current status of production, costs, inputs/outputs markets, and incomes to inform project activities and evaluate impacts.
This document discusses different types of evaporators used in various industries. It defines evaporation and describes how evaporators work by feeding a liquid solution into a heating section to evaporate water and concentrate the solution. The main types discussed are long-tube vertical, short-tube vertical, horizontal tube, forced circulation, agitated thin-film, batch pans, plate, and vapor compression evaporators. Each type is described in terms of its advantages and disadvantages as well as common industrial applications.
This document discusses microwave technology for food processing and preservation. It defines microwaves as very short radio waves that heat food through the absorption of energy by polar molecules like water. Microwaves interact with water molecules and ions, generating heat through molecular friction. Microwave sterilization can rapidly heat and sterilize foods while maintaining quality attributes like texture and color. The document also outlines key properties of microwaves, such as their ability to pass through materials like glass and air while being reflected by metals, and how they generate heat inside foods rather than just on surfaces.
This document discusses food dehydration methods, specifically tunnel drying for raisins. It provides details on:
1) Tunnel dryers are widely used to dry grapes into raisins through a heated air process. Trays of grapes are loaded into multi-tunnel concrete structures and dried over 11⁄2-2 hours with controlled air temperature, humidity, and speed.
2) Pretreatment and sulfur dioxide exposure prepares the grapes for efficient drying. Golden raisins undergo an additional sodium hydroxide dipping.
3) Key factors like 155-165°F air temperature, 88-92°F wet bulb humidity, and over 400 fpm air speed optimize drying while avoiding fruit damage.
This document discusses different types of evaporators used in various industries. It defines evaporation and describes how evaporators work by feeding a liquid solution into a heated evaporator where the applied heat converts the water in the solution into vapor which is removed. The main types discussed are long-tube vertical evaporators, short-tube vertical evaporators, horizontal tube evaporators, forced circulation evaporators, agitated thin film evaporators, batch pans, plate evaporators, and vapor compression evaporators. Each type has advantages and disadvantages for different applications in industries like food/beverage, pharmaceuticals, and pulp/paper processing.
This document discusses foodborne illness and methods of food preservation and safety regulation in the United States. It notes that foodborne illness causes significant costs and deaths each year. Common food contaminants like salmonella and E. coli are discussed. Regulations and oversight of food imports, irradiation as a preservation method, and economic costs of foodborne illness are also summarized.
A heat exchanger is a device that transfers thermal energy between fluids or between fluids and solids without mixing the substances. Heat exchangers have various applications including heating, cooling, and phase changing of fluids. In most heat exchangers, a separating wall prevents direct contact between the fluids and facilitates heat transfer through conduction. Sterilization is the process of eliminating microorganisms through physical, chemical, or other means and is important in pharmaceutical applications to prevent contamination of medical products and equipment. Several factors influence sterilization effectiveness including temperature, time, the type of microorganism, and presence of organic material.
Community nutrition deals with food and nutrition issues related to groups linked by place of residence, culture, or health issues. There is a need to focus on the community level for health promotion and disease prevention, as an individual's behaviors and attitudes are influenced by their environment. Major nutrition problems in Bangladesh include chronic energy deficiency, micronutrient deficiencies like anemia and vitamin A deficiency, and multiple deficiencies. The Bangladesh Demographic and Health Survey from 2011 shows that 41% of children under 5 are stunted, with 15.3% severely stunted.
Diet therapy involves modifying a patient's normal diet in response to disease or injury in order to meet altered nutritional requirements. The objectives of diet therapy include maintaining positive health and nutrition, correcting nutrient deficiencies, and adjusting food intake based on a person's ability to metabolize nutrients. Therapeutic diets are prescribed by doctors and are adaptations of a normal diet tailored to a patient's individual circumstances like economic status, preferences, and medical condition. Diet therapy principles include selecting easily digestible and preferred foods to maximize nutrient utilization and ensure patient cooperation, which is essential for success.
Water contamination in food processing can occur through physical, chemical, and microbiological means. Physical contamination includes heavy metals and suspended solids that affect water quality. Chemical contamination includes heavy metals, nitrates/nitrites, and arsenic, which can pose chronic health risks. Microbiological contamination, such as from E. coli and Cryptosporidium, poses the greatest concern due to immediate health risks. Proper treatment and testing of water is important in food processing to prevent contamination that could compromise food safety.
This document lists and provides brief descriptions of 10 common sexually transmitted diseases: Chlamydia, Gonorrhea, HIV/AIDS, Syphilis, Trichomoniasis, Genital Herpes, Scabies, Crabs (Pubic Lice), Hepatitis, and Bacterial Vaginosis. It focuses on Chlamydia, providing details on symptoms, diagnosis/testing, treatment, prevention, and complications if left untreated, such as pelvic inflammatory disease and infertility. For Gonorrhea, it discusses causes, prevalence, symptoms, diagnosis, and testing. For HIV/AIDS, it summarizes what it is, how it is contracted and spread, the incubation period, symptoms,
This document provides information on various survey methods and concepts. It discusses sampling methods like probability sampling (simple random sampling, systematic sampling, stratified sampling, cluster sampling, multistage sampling) and non-probability sampling (convenience sampling, purposive sampling, quota sampling). It also covers survey design types, importance of sampling, acceptable response rates, defining populations, steps in survey research, and increasing response rates. Classification of survey research methods includes temporal classification into cross-sectional and longitudinal surveys.
Maternal and child undernutrition is a serious problem in Bangladesh, with nearly half of children under five stunted and 14% suffering from wasting. Micronutrient deficiencies like iron deficiency anemia and iodine deficiency are also widespread. Inadequate childcare practices like low rates of exclusive breastfeeding and late introduction of complementary foods contribute to undernutrition. While the government and NGOs have implemented some nutrition interventions, coverage remains low and interventions have faced challenges. The government has now established the National Nutrition Service to mainstream nutrition services and implement a multi-sectoral response to reduce malnutrition in Bangladesh.
Epidemiology is defined as the study of the distribution and determinants of health-related states or events in populations, and the application of this study to control health problems. The aims of epidemiology include describing disease occurrence, assessing disease importance, explaining disease etiology, predicting disease, evaluating prevention and control, and controlling disease distribution. Common epidemiological study designs include cohort studies, case-control studies, cross-sectional studies, and occupational studies. Key epidemiological concepts include incidence, prevalence, sensitivity, specificity, and confounding factors.
1. Water sources can become contaminated by human or animal waste containing harmful bacteria and viruses.
2. Chemical contaminants like heavy metals, pesticides, and other pollutants can leach into water sources from industrial and agricultural runoff.
3. Unsafe delivery methods or storage containers can introduce physical contaminants and allow microbes to grow if water is not protected from exposure. Proper treatment and handling is needed to provide clean drinking water.
This document provides information on diet therapy and protein energy malnutrition. It discusses the objectives and principles of diet therapy, including using food to treat diseases by changing a patient's normal diet based on their condition. It also covers the classification, causes, risk factors, complications, and treatment of protein energy malnutrition, specifically marasmus and kwashiorkor. The key differences between marasmus and kwashiorkor are outlined. Prevention and management of PEM focuses on proper nutrition, hygiene, breastfeeding, and treating underlying infections.
The document provides definitions and details about various topics related to blood and the cardiovascular system. It includes:
A) Definitions of blood and its functions such as transport, regulation, and defense.
B) Descriptions of the components of blood including plasma proteins, red blood cells, clotting factors, and hemoglobin.
C) Explanations of the heart and cardiovascular system including the structure of the heart, cardiac cycle, heart sounds, and cardiovascular diseases. Common causes of CVD like atherosclerosis and hypertension are discussed.
This document provides information about Kwashiorkor, a form of severe protein malnutrition. It defines Kwashiorkor as a syndrome caused by protein deficiency characterized by stunted growth, skin changes, edema, and liver damage. Risk factors include conditions that interfere with protein absorption, low-protein diets, famine or drought, infections, limited food supply, parasites, and poor nutrition education. Symptoms include swollen stomach, brittle hair, skin discoloration, excessive weight loss, infections, fatigue, and dermatitis. Treatment involves slowly increasing calories and nutrients followed by protein supplementation along with managing infections and fluid/electrolyte imbalances. Left untreated, Kwashiorkor can cause life-threatening complications
The document discusses vitamin A, including its synthesis, absorption, storage, excretion, sources, requirements, deficiencies, treatment, and toxicity. Specifically, it describes how vitamin A intermediates can be synthesized from beta-ionone by increasing the conjugated aliphatic side chain and obtaining the trans form. It also notes that vitamin A toxicity can cause issues like dry skin, vomiting, and bone demineralization if intake exceeds 15 mg per day for adults or 6 mg per day for children over several months.
More from S. M. Mainul Islam (Nutritionist, Agriculturist) (20)
1. Suggestion of food microbiology-5005
Chapter: 02
Exam Date:15/11/2013
1. Write down the name of factors affecting the Growth of Micro-Organisms.
Factors Effecting the Growth of Micro-Organisms
Intrinsic Factors or the compositional factors of a food affecting microbial growth
• PH
• Moisture Content
• Water activity
• Oxidation-reduction potential
• Physical structure of the food
• Available nutrients
• Presence of antimicrobial agents
Extrinsic factors
• Temperature
• Relative humidity/moisture
• Carbon dioxide or oxygen
• Types and numbers of Microorganisms in the food
2. How pH effect on the Growth of Micro-Organisms.
pH effect: Every microorganism has a minimal, a maximum and an optimal pH for growth.
Microbial cells are significantly affected by the pH because the apparently have no mechanism for adjusting
their internal pH. In general, yeasts and molds are more acid tolerant than bacteria.
Foods with low pH values (below 4.5) usually are not readily spoiled by bacteria and are more susceptible
to spoilage by yeasts and molds.
Molds and Yeasts: Both are acidic pH favors them. They both can grow in a pH range of 2 to 8.
Bacteria: A pH near neutrality (pH 7.0) favors their growth
3. What is water activity? The effect of water activity on the Growth of Micro-Organisms.
Water activity (aw):
Microorganisms have an absolute demand for water. Without water no growth can occur. The exact amount
of water needed for growth of microorganisms varies. This water requirement is best expressed in terms of
available water or water activity aw.
aw = water activity = vapor pressure of food/ vapor pressure of water
aw of pure water is 1.00. Equilibrium relative humidity=aw×100. (aw below 0.70 greatly reduces microbial
growth)
Most bacteria grow at aw 0.85-1.0. Also they prefer foods with high water level.aw around 0.90.
Bacteria need more water than molds and yeasts to survive.
Mold: They can grow in low water level.(aw 0.62-0.92). Many molds are somatically tolerant and can grow at
a aw value of 0.6.
Yeasts: They prefer high water foods.( aw 0.62-0.92)
4. Classification of Micro-organism on Temperature and Oxygen
Temperature
Micro-organisms can be categorized into one of four groups depending on their optimum growth
temperature and the temperature range at which they will grow.
i) Thermophiles: Have optimum growth ca. 55 °C and a growth range of 30 - 75 °C
ii) Mesophiles: Have optimum growth ca. 35 °C and a growth range of 10 - 45 °C
iii) Psychrotrophiles: Have optimum growth ca. 20 - 30 °C and a growth range of 0 - 40 °C
Ability to use free oxygen microorganism have been classified as-
I. Aerobic- When they require free oxygen.eg. Molds are aerobic & Some bacteria are (Acetobacter)
II. An -aerobic- When they grow best in the absence of free oxygen.eg. Some bacteria are (clostridium).
III. Facultative- When they grow well either aerobically or an-aerobically.
IV. Facultative anaerobes-whey will grow in the presence or absence of oxygen eg.Yeast and some bacteria
are (bacillus).
2. 5. How dose Salt/Sugar Concentrations effect on water activity of the Growth of Micro-Organisms.
Salt/Sugar Concentrations
Most microbes cannot survive environments in which there are such high concentrations of salt or sugar.
Certain foods have long been preserved from spoilage by adding lots of salt and sugar to them. Salt and
sugar tie up the water effectively reducing the aw; salt cured ham and candied fruits are examples
3. Chapter: 03
Topic: Source and stages of microbial contamination of food.
1. #. Q. What are the Sources of microbial contamination of food?
Microorganisms are present in natural ecosystems such as air, soil and water.
They are also present on the man himself and all living animals and plants.
Therefore, all processed foods can be contaminated by microorganisms.
Eight environmental sources of microorganism found in food are given bellow-
1. Soil & water 2. Plants & plants products 3. Food utensils 4. Intestinal tract of human & animals 5. Food
handlers 6. Animal feeds 7. Animal hides 8. Air & dust
2. #. Q. Basic criteria for assurance of fitness of food?
Fitness of food:
Fitness of food will depend on person’s judgment, for what one person will eat another will not.
Some criteria for assurance of fitness:
a) The desired stage of development of maturity: Fruits should be at a certain but differing stage of
ripeness; sweet corn should be young enough to be tender and milky
b) Freedom from pollution at any stage in production or handling: Vegetables should be consumed raw if
they had been fertilized with sewage; oysters from waters contaminated with sewage should be rejected;
food handled by dirty or diseased workers should be spurned.
c) Freedom from objectionable change resulting from microbial attack or action of enzymes of the
food: Microorganisms can grow in food and can make changes which make food undesirable to accept or
consumes
3. #. Q What is spoilage? Cause of spoilage
When a food unfit for eat to sanitary reasons usually it is called spoilage.
Following cause of spoilage
a) Growth and activity of microorganisms
b) Insects
c) Action of the enzymes of the plant and animal food.
d) Purely chemical reactions. ( those not catalyzed by enzymes of the tissues or of microorganisms)
e) Physical changes, such as those caused by freezing, burning, drying, pressure etc.
4. # Q. Classification of foods by ease of spoilage
On the basis of spoilage, foods can be placed in three groups:
a. Stable or nonperishable foods: These foods, which do not spoil unless handled carelessly, include such
products as sugar, flour and dry bean.
b. Semi perishable foods: If these foods are properly handled and stored, they will remain unspoiled for a
fairly long period, e.g. potatoes, some varieties of apples, waxed rutabagas and nutmeats.
c. Perishable foods: This group includes most important daily foods that spoil readily unless special
preservative methods are used. Meats, fish, poultry, most fruits and vegetables eggs and milk belong in this
classification.
4. Chapter: 04
Topics on: Chemical changes caused by microorganisms in foods
1. Why Meat & Fish are ideal culture media?
MEAT: Meat is an ideal culture medium for many organisms because it is high in moisture, rich in
nitrogenous foods and plentifully supplied with minerals and accessory growth factors. Also, it usually has
some fermentable carbohydrate (glycogen) and is at a favorable PH
(5.7-7.2) for most microorganisms.
Problem Food Chemical Cause Organisms Involved
Rancidity Meat Fat Pseudomonas,yeast
Decomposition/hydrolysis Meat Fat Mucor
FISH: Like meat, fish is also an ideal culture medium and may spoiled by autolysis, oxidation or bacterial
activity because it is high in moisture, rich in nitrogenous foods and plentifully supplied with minerals and
accessory growth factors. Also, it usually has some fermentable carbohydrate (glycogen) and is at a
favorable PH
(5.7-7.2) for most microorganisms. Fish is more perishable than meat because of more rapid
autolysis
Problem Food Chemical Cause Organisms Involved
Slime Fish Polysacharide Pseudomonas
H2S/Mercaptans Fish Non protein nitrogen Pseudomonas
2. Why Milk is the excellent culture media?
Milk is an excellent culture medium for many kinds of microorganisms, being high in moisture, neutral in pH
(7.0 ) and rich in microbial foods.
Problem Food Chemical Cause Organisms Involved
Ropiness Milk Polysaccharides Alcaligenes,
Brown Milk Milk Tyrosine (oxidation) Pseudomonas
3. What is fermentation? Ropiness of Bread and milk
Fermentation is a metabolic process in which an organism converts a carbohydrate, such as starch or a
sugar, into an alcohol or an acid.
For example, yeast performs fermentation to obtain energy by converting sugar into alcohol. Bacteria
perform fermentation, converting carbohydrates into lactic acid.
Ropiness is a defect in food caused by the growth of undesirable bacteria. It is usually characterized by
stringiness, increased viscosity or sliminess.
Product Name Chemical cause Microorganism
Ropiness of Bread Gluten, Polysaccharides Alcaligenes, Bacillus
Ropiness of Milk Polysaccharides Alcaligenes,
4. Which chemicals are changes in cereal?
Chemical change in cereal grains and meals:
Cereals contain sugar and nitrogen compounds, minerals and accessory growth substances.
If moisture level of whole grain contain low (below 11% moisture) than the spoilage by microorganisms is
inhibited but if they are moistened then growth of microorganisms is accelerated.
Wet meals will undergo an acid fermentation, chiefly by the lactic acid and Coliform bacteria. This may be
followed by an alcoholic fermentation by yeasts. Finally mold and yeast will grow on the top surface.
Main chemical change occurs in cereal and cereals products cause by fermentation.
Cereals:
Problem Product Chemical cause Microorganism
Sour Grain, meal,
Bread
Polysaccharides Acetobacter, Lactobacillus,Coliform
Sticky dough Bread Gluten Proteolytic bacteria
Mustiness Bread, Cake Chloroanisoles Moulds
Ropiness Bread Gluten,Polysaccharides Alcaligenes,.Bacillus
Slime Confectionery Polysaccharide Pseudomonas,Leuconostoc, Bacillus
5. 5. Which chemicals are changes in Milk?
Milk products: Milk and cream, butter, cheese, condensed and dried milk products etc.
Milk is an excellent culture medium for many kinds of microorganisms, being high in moisture, neutral in pH
(7.0) and rich in microbial foods.
Contamination:
Milk contamination of manure, soil and water and also from utensils
Microorganism: Bacteria: Enterococcus, Micrococcus, Bacillus,Sarcina, Serratia etc.
Problem Product Chemical cause Microorganism
Souring Milk, Cheese Acids: acetic, lactic, citric,
butyric
Lactic acid bacteria Bacillus
Butyric acid bacteria Acetobacter
Ropiness Milk Polysaccharides Alcaligenes,
Holes Hard cheese (gas production) Coliforms
Curdling Milk Acid production Lactic acid bacteria
Gas Milk Carbohydrate Lactobacillus,Clostridium
Proteolysis Milk Protein Yeast/mold, lactic acid bacteria
Bitter flavor Milk Lactose (fermentation) Coliform,Yeasts
Brown Milk Milk Tyrosine (oxidation) Pseudomonas
6. Why an whole made on heart cheese.
6. Chapter: 05
1. Classified Bacteria based on structure, metabolism and temperature sensitivity.
Bacteria can have three basic shapes
1. Cocci – sphere-shaped
• Plural is Cocci.
• Spherical bacterium
• Single cells - Monococci
• Pairs - Diplococci
• Chains - Streptococci
2. Bacilli – rod-shaped
• Plural is bacilli.
• A rod - shaped bacterium.
• Exists as single cells, in pairs
(diplobacilli), and
in chains (streptobacilli)
3. Spirilla – spiral-shaped
• Plural is Spirilli
• A spiral - Shaped bacterium.
• Exist only as single cells.
Modes of Nutrition/metabolism:
Bacterial Physiology-Nutritional Needs
The two categories are,
1. Heterotrophic Bacteria
Heterotrophs must get their food from a source of pre-formed organic matter:
Saprobes – feed on dead organic matter
Parasites – feed on a host cell-Example, Mycobacterium tuberculosis
Photoautotroph – use sunlight to make food
Chemoautotroph – oxidize inorganic matter such as iron or sulfur to make food
2. Autotrophic Bacteria
Autotrophs- can make their own food:
Photosynthetic-use a special type of chlorophyll called bacteriochlorophyll.
O2 is not released in bacterial photosynthesis
Chemosynthetic -obtain energy by breaking down inorganic material such as iron or sulfur.
Bacteria are classified based on temperature are as follows:
Mesophiles : Those bacteria grow best at ambient temperature (20°C to 40°C)
Thermophiles : Those have an optimum temperature above 450
C
Psychrophiles : Grow best from about at 0-150
C
Extremophiles : Grow well at 100-1200
C
2. Distinguished Bacteria and Virus.
SL Characteristics Bacteria Virus
01 Number of cells: Unicellular; one cell No cells; not living
02 Organism Living organisms Not living
03 Cell Prokaryotic cells Not made of cells
04 Survivability are always alive dead or alive in living cell
05 Reproduction Can replicate on its own Requires a host cell to replicate
06 Treatment Can be treated with antibiotics Can be prevented with vaccine
07 Genetic materials DNA DNA or RNA.
08 Enzymes Yes Yes, in some
09 Infection Localized Systemic
10 Visible Visible under Light Microscope Visible only under Electron Microscope
11 Size Larger (1000nm) Smaller (20 - 400nm)
7. 3. Distinguished Yeast and Molds.
Yeasts-“fungi, unicellular, asexual reproduction through budding, colorless parasite
Molds- fungi, multi-cellular, sexual& asexual reproduction, colorful parasite
4. Distinguished Bacteria & Fungi.
Bacteria Fungi
Bacteria are prokaryotes Fungi are eukaryotes
Bacteria are single celled Fungi are multi-cellular except for yeast
Bacteria can be autotrophy or heterotrophy Fungi are heterotrophy
Bacteria have 3 distinct shapes Fungi have various shapes.
Bacteria reproduce sexually via binary fusion Fungi are capable of reproducing both sexually or asexually.
5. Explain the growth curve of Bacteria.
The growth curve of Bacteria: In studies, bacterial growth four different phases
Fig. Bacterial Growth Curve
1. Lag phase: During the lag phase of the bacterial growth cycle, synthesis of RNA, enzymes and other
molecules occurs.
2. Growth phase/ exponential phase is a period characterized by cell doubling. The number of new bacteria
appearing per unit time is proportional to the present population. For this type of exponential growth, plotting
the natural logarithm of cell number against time produces a straight line. The actual rate of this growth (i.e.
the slope of the line in the figure) depends upon the growth conditions, which affect the frequency of cell
division events and the probability of both daughter cells surviving.
3. Stationary phase: Stationary phase results from a situation in which growth rate and death rate are equal.
The number of new cells created is limited by the growth factor and as a result the rate of cell growth
matches the rate of cell death. The result is a “smooth,” horizontal linear part of the curve during the
stationary phase.
4. Death phase, bacteria run out of nutrients and die.
8. 6. Write name of some virus and disease produced by them.
SL# Name of Virus Name of Disease
Virus that affect Animal
1 Human immune deficiency virus Acquired Immune Deficiency Syndrome (AIDS)
2 Corona virus - common cold
3 Onco viruses Cancer
4 Hepatitis C viruses Hepatitis
5 Marburg virus, Ebola virus hemorrhagic fever
6 Rabies virus Rabies
7 Mumps virus Virus
8 Influenza viruses, types A, B, C Influenza
9 Yellow fever virus causes yellow fever,
10 Poliovirus Polio
11 Foot and Mouth Disease virus Foot and Mouth Disease
Virus that affect Plant
01 Rice tungro bacilliform virus (RTBV) Tungro
02 Wheat draft virus (WDV) Wheat draft
03 Jute Mosaic Virus (JMV) Chlorosis
04 Papaya Mosaic Virus (PMV) Yellow Mosaic
05 Potato Leaf Curl Virus (PLCV) Leaf Curl
06 Bunchy Top Virus (BTV) Bunchy Top
07 Potato Leaf Roll Virus (PLRV) Leaf Roll
7. Example of Round shape and Rod Shape Virus.
Rod shape Virus: tobacco mosaic disease virus, potato mosaic disease virus, turnip yellows mosaic virus
Round shape Virus: Influenza virus
8. What is mycosis? Illustrate different types of mycosis inhuman.
Mycosis: Mycosis is a fungal infection of animals, including humans. A variety of environmental and
physiological conditions can contribute to the development of fungal diseases. Inhalation of fungal spores or
localized colonization of the skin may initiate persistent infections; therefore, mycoses often start in the
lungs or on the skin
Types of mycoses:
1. Superficial mycoses: In superficial mycoses infection is localized to the skin, the hair, and the nails such
as ringworm. Candida albicans is yeast causing candidiasis or "thrush" in humans as superficial mycoses,
candidiasis typically infects the mouth or vagina is part of the normal flora of the vagina and gastrointestinal
tract and is termed a "commensal.
2. Cutaneous: Mycosis or darmatomycosis include such infections as athlete’s foot and ringworm, where
growth occurs only in the superficial layers of skin, nails or hair.
3. Subcutaneous mycoses: These are infections confined to the dermis, subcutaneous tissue or adjacent
structures. Infection may arise following the wounding of the skin and the introduction of vegetable matter.
Infection usually follows and insect bite, thorn pricks or scratches from a fish spine.
4. Systemic mycoses: These are invasive infections of the internal organs with the organism gaining entry by
the lungs, gastrointestinal tract or through intravenous lines.
They may be caused by: (i) primary pathogenic fungi or (ii) by opportunistic fungi that are of marginal
pathogenicity
Examples include histoplasmosis, blastomycosis, coccidiomycosis and paracoccidiodomycosis.
9. 9. What do you mean by staining? Explaining about Gram Staining Procedure.
Staining:
Staining is used in microscopy to enhance contrast in the microscopic image. Stains may be used to define
and examine bulk tissues, cell populations (classifying different blood cells, for instance), or organelles
within individual cells.
The Gram Staining Procedure:
Equipment: Bunsen burner, alcohol-cleaned microscope slide, water
Reagents: Crystal violet, Gram's iodine solution, acetone/ethanol (50:50 v:v), 0.1% basic fuchsine solution
Procedures:
1. Prepare a Slide Smear:
A. Transfer a drop of the suspended culture to be examined on a slide with an inoculation loop. If staining a
clinical specimen, smear a very thin layer onto the slide, using a wooden stick. The smear should be thin
enough to dry completely within a few seconds.
B. Spread the culture with an inoculation loop to an even thin film over a circle of 1.5 cm in diameter. Thus,
a typical slide can simultaneously accommodate 3 to 4 small smears if more than one culture is to be
examined.
C. Air-dry the culture and fix it or over a gentle flame, e.g. taking the slide in and out of the flame.
2. Gram Staining:
A. Add crystal violet stain over the fixed culture. Let stand for 10 to 60 seconds; Note that the objective of
this step is to wash off the stain, not the fixed culture.
B. Add the iodine solution on the smear, enough to cover the fixed culture. Let stand for 10 to 60 seconds
and rinse the slide with running water. Shake off the excess water from the surface.
C. Add a few drops of decolorizer. Rinse it off with water after 5 seconds.
D. Counter stain with basic fuchsine solution for 40 to 60 seconds. Alternatively, the slide may shake to
remove most of the water and air-dried.
3. Quality control:
This should be smeared into a drop of clean tap water on a clean glass slide.
4. Examine the finished slide under a microscope.
Filamentous and pleomorphic forms may be observed among the Gram (-) rod species.
Gram reaction of the organism may also change after antimicrobial therapy, Gram (+) bacterial may
become gram variable.
10. Draw an ideal bacterial cell and indicated its different parts.
10. 11. Why Agar use in cultural media
12. What is selective and indicator media?
13. What is food born infection and food intoxication
11. Chapter: 06
1. Why estimating the number of microorganism?
2. Why aseptic collection of sample for microorganism
3. What is direct Microscopic count? Value of DMC
4. Principal of electric particle count.
5. Compare between Pour plating and spread plating technique
6. Discus membrane filters techniques. Advantage and disadvantage of membrane filters techniques
7. Define reductase .Indicate several procedure that can be estimate the number of viable microorganism.
Note: (A)
I think you avoid this chapter
for exam preparation, OK.
‡bvU: (A) y
Kgc‡¶ mvZ (7) evi †`‡L †`‡L covi ci,
3.5 evi a¨vb gZ ï‡q †PvL eÜ K‡i
g‡b g‡b DËi ¸‡jv fve‡Z _v‡Kb Ges
†kl m¤¢j wnmv‡e msw¶ß ‡bvU
eBwU me mgq Avcbvi mv‡_ ivLyb,
hv‡Z g‡b bv _vK‡j Avcwb †bvU eB
†`‡L cix¶vi LvZvq wjL‡Z cv‡ib |