Bacteria can divide through binary fission or other means like budding or fragmentation. The average generation time for bacteria is 1-3 hours, with E. coli taking 20 minutes to divide. Bacterial growth follows distinct phases on a growth curve: lag phase, log/exponential phase, stationary phase, and death phase. Factors like nutrients, temperature, pH, and oxygen levels influence bacterial growth. Diauxic growth occurs when bacteria sequentially utilize two different nutrients for growth. Synchronous bacterial growth can be achieved through techniques like nutrient depletion and addition or physical separation methods. Maintaining bacterial cultures involves isolating pure cultures and continuous culture techniques like chemostat systems.
The presentation covers various areas in bacteriology such as bacterial binary fission, Bacterial growth curve, synchronous growth and continuous growth, Isolation of bacterial pure culture and Preservation of bacterial pure culture.
Lecture.pptx microbial growth and development in food and processingSaadiyaNaqash2
This document discusses microbial growth and control. It covers:
1) Microorganisms grow and multiply when exposed to a favorable environment like food, leading to food spoilage, diseases, or bioprocessing. Their growth is measured by increases in cell numbers or mass.
2) Bacteria reproduce through binary fission. The generation time or doubling time is the time it takes a single cell to divide into two cells. Growth curves show lag, log, stationary, and death phases of microbial growth.
3) Various physical and chemical agents can be used to control microbial growth, including heat, radiation, filtration, and antimicrobial chemicals. Their mode of action includes damaging cell walls or membranes and inhibiting
Definition of bacterial growth
Modes of multiplication in bacteria
List the salient features of bacterial growth curve.
Concepts of generation time and growth curve
Calculations of generation time
1. The document discusses the growth and reproduction of microorganisms like bacteria through binary fission or budding. It describes the four phases of bacterial growth in a closed culture system: lag phase, exponential phase, stationary phase, and death phase.
2. It also discusses the requirements and classification of culture media used to grow bacteria in the laboratory, including nutrient composition, consistency (solid, liquid, semisolid), and purpose (ordinary, special, enrichment, selective, diagnostic, conservation).
3. Key physical factors that influence microbial growth are also outlined, such as temperature, pH, and oxygen concentration. Most bacteria grow best around human body temperature and neutral pH.
Growth & multiplication of Microorganism. The main principles of bacteria cul...Eneutron
1. The document discusses the growth and reproduction of microorganisms like bacteria through binary fission or budding. It describes the four phases of bacterial growth in a closed culture system: lag phase, exponential phase, stationary phase, and death phase.
2. It also discusses the requirements and classification of culture media used to grow bacteria in the laboratory, including nutrient composition, consistency (solid, liquid, semisolid), and purpose (ordinary, special, enrichment, selective, diagnostic, conservation).
3. Physical factors like temperature, pH, and oxygen concentration that influence microbial growth are also outlined.
This document provides information about the course AMBE-101 Agricultural Microbiology which is worth 2 credits and includes a 1 hour lecture and 1 hour lab. It discusses various topics related to microbial growth including bacterial reproduction methods, factors affecting growth, growth curves and phases, synchronous growth, and continuous culture techniques like chemostats which are used to maintain bacterial cultures in exponential phase. Continuous culture using a chemostat works by maintaining a constant dilution rate and limiting nutrient concentration to control bacterial growth rate and keep cell density constant.
This document discusses various types of bacterial growth and nutrition. It begins by describing autotrophs and heterotrophs, and how they obtain nutrients. It then discusses different types of autotrophs like photoautotrophs and chemoautotrophs. The document also covers bacterial growth curves, including the lag, logarithmic, stationary and death phases. It describes continuous culture techniques used to maintain bacterial growth. Measurement of bacterial growth through serial dilutions and turbidity analysis is also summarized.
Doctors Data Inc A Revolution in the Evaluation of Gastrointestinal MicrofloraBonnieReynolds4
Recent research regarding the gastrointestinal microbiome has irrefutably confirmed the fact that the
microbial inhabitants of the gastrointestinal tract, and their astonishing scope of metabolic activities,
are at the very core of health and numerous disease processes. It is also clear that clinical microbiology
testing should be optimized to address the relative abundance of all bacterial species present in a stool
specimen.
The presentation covers various areas in bacteriology such as bacterial binary fission, Bacterial growth curve, synchronous growth and continuous growth, Isolation of bacterial pure culture and Preservation of bacterial pure culture.
Lecture.pptx microbial growth and development in food and processingSaadiyaNaqash2
This document discusses microbial growth and control. It covers:
1) Microorganisms grow and multiply when exposed to a favorable environment like food, leading to food spoilage, diseases, or bioprocessing. Their growth is measured by increases in cell numbers or mass.
2) Bacteria reproduce through binary fission. The generation time or doubling time is the time it takes a single cell to divide into two cells. Growth curves show lag, log, stationary, and death phases of microbial growth.
3) Various physical and chemical agents can be used to control microbial growth, including heat, radiation, filtration, and antimicrobial chemicals. Their mode of action includes damaging cell walls or membranes and inhibiting
Definition of bacterial growth
Modes of multiplication in bacteria
List the salient features of bacterial growth curve.
Concepts of generation time and growth curve
Calculations of generation time
1. The document discusses the growth and reproduction of microorganisms like bacteria through binary fission or budding. It describes the four phases of bacterial growth in a closed culture system: lag phase, exponential phase, stationary phase, and death phase.
2. It also discusses the requirements and classification of culture media used to grow bacteria in the laboratory, including nutrient composition, consistency (solid, liquid, semisolid), and purpose (ordinary, special, enrichment, selective, diagnostic, conservation).
3. Key physical factors that influence microbial growth are also outlined, such as temperature, pH, and oxygen concentration. Most bacteria grow best around human body temperature and neutral pH.
Growth & multiplication of Microorganism. The main principles of bacteria cul...Eneutron
1. The document discusses the growth and reproduction of microorganisms like bacteria through binary fission or budding. It describes the four phases of bacterial growth in a closed culture system: lag phase, exponential phase, stationary phase, and death phase.
2. It also discusses the requirements and classification of culture media used to grow bacteria in the laboratory, including nutrient composition, consistency (solid, liquid, semisolid), and purpose (ordinary, special, enrichment, selective, diagnostic, conservation).
3. Physical factors like temperature, pH, and oxygen concentration that influence microbial growth are also outlined.
This document provides information about the course AMBE-101 Agricultural Microbiology which is worth 2 credits and includes a 1 hour lecture and 1 hour lab. It discusses various topics related to microbial growth including bacterial reproduction methods, factors affecting growth, growth curves and phases, synchronous growth, and continuous culture techniques like chemostats which are used to maintain bacterial cultures in exponential phase. Continuous culture using a chemostat works by maintaining a constant dilution rate and limiting nutrient concentration to control bacterial growth rate and keep cell density constant.
This document discusses various types of bacterial growth and nutrition. It begins by describing autotrophs and heterotrophs, and how they obtain nutrients. It then discusses different types of autotrophs like photoautotrophs and chemoautotrophs. The document also covers bacterial growth curves, including the lag, logarithmic, stationary and death phases. It describes continuous culture techniques used to maintain bacterial growth. Measurement of bacterial growth through serial dilutions and turbidity analysis is also summarized.
Doctors Data Inc A Revolution in the Evaluation of Gastrointestinal MicrofloraBonnieReynolds4
Recent research regarding the gastrointestinal microbiome has irrefutably confirmed the fact that the
microbial inhabitants of the gastrointestinal tract, and their astonishing scope of metabolic activities,
are at the very core of health and numerous disease processes. It is also clear that clinical microbiology
testing should be optimized to address the relative abundance of all bacterial species present in a stool
specimen.
Isolation and identification of protease producing bacteriaIRJET Journal
This document discusses the isolation and identification of protease-producing bacteria. It begins by introducing proteases and their importance in industrial applications. It then describes the common techniques used to isolate bacteria from samples, including streak plating and pour plating. After isolation, bacteria are identified using morphological, biochemical, and newer molecular characterization methods. The goal of the document is to provide information on isolating and identifying protease-producing bacteria specifically from soil, kitchen waste, and tannery sources.
Microbial growth involves an increase in cell numbers through cell division and reproduction. There are four phases of microbial growth: lag phase as cells adapt to their environment; log or exponential phase of rapid cell division; stationary phase as resources are depleted and growth balances mortality; and death phase as cells die off. Microbial growth is influenced by environmental factors like pH, temperature, gas availability, and pressure.
This document provides information about a seminar on micropropagation techniques in fruit crops. It discusses the need for micropropagation due to issues like seasonal limitations and virus transmission. The advantages of micropropagation include producing true-to-type plants, overcoming seasonal constraints, and allowing large-scale multiplication. The document outlines the stages of micropropagation including establishment, proliferation, rooting, and acclimatization. It also describes different approaches like axillary budding and somatic embryogenesis. Several case studies demonstrate the use of micropropagation in plants like date palm, mango, and lemon.
The document discusses microbial metabolism and growth kinetics. It describes how microbes obtain energy through metabolic pathways like glycolysis and the citric acid cycle. Glycolysis converts glucose to pyruvate, producing ATP and NADH. The citric acid cycle further oxidizes pyruvate, also generating ATP. The document also discusses the glyoxylate cycle, which allows microbes to use acetate to produce succinate. Microbial growth kinetics and methods of measuring growth like plate counts and turbidity are also summarized. Microbes can live as single cells or form biofilms, which increase habitat range and stress tolerance through cooperation of diverse members.
1. The document discusses microbial growth curves and the different phases of bacterial growth: lag, exponential, stationary, and death phase.
2. It explains key concepts like generation time, growth rate constant, batch and continuous culture techniques, and the importance of understanding growth curves.
3. The mathematics of growth is also covered, including definitions and calculations of generation time and growth rate constant.
Microbial growth refers to an increase in number of cells rather than an incr...Smitha Vijayan
Microbial growth refers to an increase in the number of cells rather than size. Most bacteria reproduce through binary fission, where the cell elongates, replicates its DNA, and divides into two daughter cells through septum formation. Some bacteria use other mechanisms like budding or multiple fission. The bacterial cell cycle consists of a growth phase, DNA replication/partitioning phase, and cytokinesis phase to form daughter cells. Environmental factors like temperature, nutrients, and waste accumulation influence the growth curve phases of lag, exponential, stationary, and death phases. Microbes have adapted mechanisms to grow at different temperatures ranges through modifications to enzymes, membranes, and other cellular components.
The document summarizes key aspects of microbial growth kinetics, including batch, fed-batch, and continuous growth systems. It describes the four phases of microbial growth - lag, log, stationary, and death phases. The log phase is characterized by exponential growth and doubling time. The stationary phase occurs when substrate is depleted and growth rate equals death rate. Specific growth rate and its relationship to substrate concentration and maximum growth rate is defined by the Monod equation.
Lecture 5 bioprocess technology, operation mode and scaleDr. Tan Boon Siong
This document discusses different bioprocess cultivation systems and operation modes. It covers two-phase and three-phase cultivation systems, as well as free and immobilized cell systems. Batch, fed-batch, and continuous cultivation modes are described in detail. Specific topics covered include microbial growth curves, factors affecting lag phase, kinetics of exponential and stationary phases, and product formation under different operation modes. Advantages of fed-batch cultivation like avoiding inhibition and catabolite repression are highlighted. High cell density cultivation using exponential feeding strategies is also summarized.
Reproduction and growth of bacteria by TanzirTanzir Ahmed
This document provides information about various modes of bacterial reproduction and growth. It discusses binary fission as the main form of asexual reproduction in bacteria, where the parent cell divides into two identical daughter cells. The normal bacterial growth cycle is described through four phases: lag phase, log or exponential phase, stationary phase, and death phase. Methods for measuring bacterial growth include direct microscopic counting, plate counts, and indirect techniques like turbidity measurements and assessing metabolic activity. Synchronous bacterial cultures aim to study all cells at the same stage of the cell cycle for more precise analyses.
This document discusses types of microbial culture and growth kinetics. It describes three types of microbial culture: batch culture, fed-batch culture, and continuous culture. For batch culture, it outlines the six phases of microbial growth: lag phase, accelerated phase, exponential growth phase, decelerated growth phase, stationary phase, and death phase. Fed-batch culture involves incrementally adding nutrients over time to prolong the log and stationary phases. Continuous culture maintains a steady cell population by continuously adding and removing medium. The advantages of continuous culture are that it avoids downtime between batches and produces more consistent yields, while its disadvantages include greater difficulty maintaining sterility and potential cell loss.
Isolation of bacteria is an important step in diagnosing bacterial infections. There are various methods used for isolating bacteria, including culture methods using solid or liquid media, and non-culture methods like PCR. For culture, appropriate specimens are collected and transported to the lab, where microscopy is first performed to view bacteria. The specimens are then plated on selective and non-selective media and incubated under optimal conditions for bacterial growth. Isolates are identified based on colony characteristics. Automated systems can also be used to more rapidly detect bacterial growth through liquid culture.
Isolation of bacteria is an important step in diagnosing bacterial infections. There are various methods used for isolating bacteria, including culture methods using solid or liquid media, and non-culture methods like PCR. For culture, appropriate specimens are collected and transported to the lab, where microscopy is first performed to view bacteria. The specimens are then plated on selective and non-selective media and incubated under optimal conditions for bacterial growth. Isolates are identified based on colony characteristics. Automated systems can also be used to more rapidly detect bacterial growth through liquid culture.
Microbial biofilms pathogenicity and treatment strategiesPratyush Kumar Das
Microbial biofilms are complex structures wherein the planktonic cells change their growth mode to the sessile form. This kind of growth is assisted by the formation of a matrix of extracellular polymeric substances (EPS) which encapsulates the bacterial cells within it and thus, provides an additional protection. These biofilms are highly resistant to high concentration of antibiotics and poses a great threat towards public health. These biofilms are even beyond the access of a normal human immune system and are involved in infections of teeth, lungs and many other diseases. There lies an immediate need to replace the extensive use of antibiotics with new emerging strategies. The review intends to provide an insight on the various perspectives of microbial biofilms including their formation, composition, mechanism of communication (Quorum sensing) and pathogenicity. Recent emerging strategies have also been discussed that can be considered for successful eradication or inhibition of biofilms and related infections.
The document summarizes the bacterial growth curve, which shows the characteristic pattern of bacterial population growth over time when bacteria are inoculated into fresh liquid medium. The growth curve consists of four phases: 1) Lag phase where bacteria adjust to the new environment before dividing, 2) Log or exponential phase where bacteria divide rapidly at a constant rate, 3) Stationary phase where growth balances with death resulting in no net population change, and 4) Death phase where the population declines due to nutrient depletion and waste accumulation.
The bacterial growth curve represents the number of live cells in a bacterial population over a period of time. There are four distinct phases of the growth curve: lag, exponential (log), stationary, and death.
B.sc. Microbiology II Bacteriology Unit 4.1 Bacterial GrowthRai University
This document discusses bacterial growth and the requirements for bacterial growth. It covers the following key points:
1. Bacterial growth occurs through binary fission where a single bacterium divides into two daughter cells. The number of bacterial cells increases exponentially in the exponential growth phase until resources are depleted.
2. Bacteria require carbon, nitrogen, phosphorus, sulfur, water, and trace elements as nutrients for growth. Carbon is obtained from organic sources or carbon dioxide. Nitrogen sources include amino acids, ammonia, and nitrates.
3. In addition to macro nutrients, bacteria may also require small amounts of organic growth factors like vitamins, amino acids, and nucleic acid precursors to support their metabolism and growth
B.Sc. Microbiology IV Bacteriology Unit 4.1 Bacterial GrowthRai University
This document discusses bacterial growth and the requirements for bacterial growth. It covers the following key points:
1. Bacterial growth occurs through binary fission where a parent cell divides into two identical daughter cells. Exponential growth occurs when each new cell divides.
2. Bacteria require nutrients like carbon, nitrogen, sulfur, phosphorus and micronutrients for growth. Carbon sources include CO2, organic molecules, and reduced inorganic molecules. Nitrogen sources include amino acids, ammonia, nitrates and nitrogen gas.
3. In addition to macro/micronutrients, some bacteria also require small amounts of organic growth factors like vitamins, amino acids and nucleic acid precursors to support their metabolism.
1) The document discusses microbial growth and culture. It defines microbial growth as the asexual reproduction of bacteria through binary fission to produce two daughter cells identical to the original.
2) Bacterial culture is described as multiplying microbes by letting them reproduce in a controlled laboratory environment with a predetermined culture medium.
3) Four phases of microbial growth are outlined: lag phase, log/exponential phase, stationary phase, and death phase. The lag phase involves only cell size increase while the log phase enables maximum growth and reproduction through binary fission. In stationary phase, cell division and death are equal while death phase involves shortage of nutrients and accumulation of toxins leading to cell death.
This document discusses various topics related to bacterial growth, including the different phases of bacterial growth (lag, log, stationary, death), factors that affect growth, and different types of bacterial growth (diauxic, synchronous, continuous). It provides details on each growth phase and explains that bacteria must be in a suitable environment to grow. The intrinsic and extrinsic factors that influence growth are listed. Diauxic, synchronous, and continuous growth are also summarized, along with details on turbidostat and chemosat methods for continuous growth.
Isolation and identification of protease producing bacteriaIRJET Journal
This document discusses the isolation and identification of protease-producing bacteria. It begins by introducing proteases and their importance in industrial applications. It then describes the common techniques used to isolate bacteria from samples, including streak plating and pour plating. After isolation, bacteria are identified using morphological, biochemical, and newer molecular characterization methods. The goal of the document is to provide information on isolating and identifying protease-producing bacteria specifically from soil, kitchen waste, and tannery sources.
Microbial growth involves an increase in cell numbers through cell division and reproduction. There are four phases of microbial growth: lag phase as cells adapt to their environment; log or exponential phase of rapid cell division; stationary phase as resources are depleted and growth balances mortality; and death phase as cells die off. Microbial growth is influenced by environmental factors like pH, temperature, gas availability, and pressure.
This document provides information about a seminar on micropropagation techniques in fruit crops. It discusses the need for micropropagation due to issues like seasonal limitations and virus transmission. The advantages of micropropagation include producing true-to-type plants, overcoming seasonal constraints, and allowing large-scale multiplication. The document outlines the stages of micropropagation including establishment, proliferation, rooting, and acclimatization. It also describes different approaches like axillary budding and somatic embryogenesis. Several case studies demonstrate the use of micropropagation in plants like date palm, mango, and lemon.
The document discusses microbial metabolism and growth kinetics. It describes how microbes obtain energy through metabolic pathways like glycolysis and the citric acid cycle. Glycolysis converts glucose to pyruvate, producing ATP and NADH. The citric acid cycle further oxidizes pyruvate, also generating ATP. The document also discusses the glyoxylate cycle, which allows microbes to use acetate to produce succinate. Microbial growth kinetics and methods of measuring growth like plate counts and turbidity are also summarized. Microbes can live as single cells or form biofilms, which increase habitat range and stress tolerance through cooperation of diverse members.
1. The document discusses microbial growth curves and the different phases of bacterial growth: lag, exponential, stationary, and death phase.
2. It explains key concepts like generation time, growth rate constant, batch and continuous culture techniques, and the importance of understanding growth curves.
3. The mathematics of growth is also covered, including definitions and calculations of generation time and growth rate constant.
Microbial growth refers to an increase in number of cells rather than an incr...Smitha Vijayan
Microbial growth refers to an increase in the number of cells rather than size. Most bacteria reproduce through binary fission, where the cell elongates, replicates its DNA, and divides into two daughter cells through septum formation. Some bacteria use other mechanisms like budding or multiple fission. The bacterial cell cycle consists of a growth phase, DNA replication/partitioning phase, and cytokinesis phase to form daughter cells. Environmental factors like temperature, nutrients, and waste accumulation influence the growth curve phases of lag, exponential, stationary, and death phases. Microbes have adapted mechanisms to grow at different temperatures ranges through modifications to enzymes, membranes, and other cellular components.
The document summarizes key aspects of microbial growth kinetics, including batch, fed-batch, and continuous growth systems. It describes the four phases of microbial growth - lag, log, stationary, and death phases. The log phase is characterized by exponential growth and doubling time. The stationary phase occurs when substrate is depleted and growth rate equals death rate. Specific growth rate and its relationship to substrate concentration and maximum growth rate is defined by the Monod equation.
Lecture 5 bioprocess technology, operation mode and scaleDr. Tan Boon Siong
This document discusses different bioprocess cultivation systems and operation modes. It covers two-phase and three-phase cultivation systems, as well as free and immobilized cell systems. Batch, fed-batch, and continuous cultivation modes are described in detail. Specific topics covered include microbial growth curves, factors affecting lag phase, kinetics of exponential and stationary phases, and product formation under different operation modes. Advantages of fed-batch cultivation like avoiding inhibition and catabolite repression are highlighted. High cell density cultivation using exponential feeding strategies is also summarized.
Reproduction and growth of bacteria by TanzirTanzir Ahmed
This document provides information about various modes of bacterial reproduction and growth. It discusses binary fission as the main form of asexual reproduction in bacteria, where the parent cell divides into two identical daughter cells. The normal bacterial growth cycle is described through four phases: lag phase, log or exponential phase, stationary phase, and death phase. Methods for measuring bacterial growth include direct microscopic counting, plate counts, and indirect techniques like turbidity measurements and assessing metabolic activity. Synchronous bacterial cultures aim to study all cells at the same stage of the cell cycle for more precise analyses.
This document discusses types of microbial culture and growth kinetics. It describes three types of microbial culture: batch culture, fed-batch culture, and continuous culture. For batch culture, it outlines the six phases of microbial growth: lag phase, accelerated phase, exponential growth phase, decelerated growth phase, stationary phase, and death phase. Fed-batch culture involves incrementally adding nutrients over time to prolong the log and stationary phases. Continuous culture maintains a steady cell population by continuously adding and removing medium. The advantages of continuous culture are that it avoids downtime between batches and produces more consistent yields, while its disadvantages include greater difficulty maintaining sterility and potential cell loss.
Isolation of bacteria is an important step in diagnosing bacterial infections. There are various methods used for isolating bacteria, including culture methods using solid or liquid media, and non-culture methods like PCR. For culture, appropriate specimens are collected and transported to the lab, where microscopy is first performed to view bacteria. The specimens are then plated on selective and non-selective media and incubated under optimal conditions for bacterial growth. Isolates are identified based on colony characteristics. Automated systems can also be used to more rapidly detect bacterial growth through liquid culture.
Isolation of bacteria is an important step in diagnosing bacterial infections. There are various methods used for isolating bacteria, including culture methods using solid or liquid media, and non-culture methods like PCR. For culture, appropriate specimens are collected and transported to the lab, where microscopy is first performed to view bacteria. The specimens are then plated on selective and non-selective media and incubated under optimal conditions for bacterial growth. Isolates are identified based on colony characteristics. Automated systems can also be used to more rapidly detect bacterial growth through liquid culture.
Microbial biofilms pathogenicity and treatment strategiesPratyush Kumar Das
Microbial biofilms are complex structures wherein the planktonic cells change their growth mode to the sessile form. This kind of growth is assisted by the formation of a matrix of extracellular polymeric substances (EPS) which encapsulates the bacterial cells within it and thus, provides an additional protection. These biofilms are highly resistant to high concentration of antibiotics and poses a great threat towards public health. These biofilms are even beyond the access of a normal human immune system and are involved in infections of teeth, lungs and many other diseases. There lies an immediate need to replace the extensive use of antibiotics with new emerging strategies. The review intends to provide an insight on the various perspectives of microbial biofilms including their formation, composition, mechanism of communication (Quorum sensing) and pathogenicity. Recent emerging strategies have also been discussed that can be considered for successful eradication or inhibition of biofilms and related infections.
The document summarizes the bacterial growth curve, which shows the characteristic pattern of bacterial population growth over time when bacteria are inoculated into fresh liquid medium. The growth curve consists of four phases: 1) Lag phase where bacteria adjust to the new environment before dividing, 2) Log or exponential phase where bacteria divide rapidly at a constant rate, 3) Stationary phase where growth balances with death resulting in no net population change, and 4) Death phase where the population declines due to nutrient depletion and waste accumulation.
The bacterial growth curve represents the number of live cells in a bacterial population over a period of time. There are four distinct phases of the growth curve: lag, exponential (log), stationary, and death.
B.sc. Microbiology II Bacteriology Unit 4.1 Bacterial GrowthRai University
This document discusses bacterial growth and the requirements for bacterial growth. It covers the following key points:
1. Bacterial growth occurs through binary fission where a single bacterium divides into two daughter cells. The number of bacterial cells increases exponentially in the exponential growth phase until resources are depleted.
2. Bacteria require carbon, nitrogen, phosphorus, sulfur, water, and trace elements as nutrients for growth. Carbon is obtained from organic sources or carbon dioxide. Nitrogen sources include amino acids, ammonia, and nitrates.
3. In addition to macro nutrients, bacteria may also require small amounts of organic growth factors like vitamins, amino acids, and nucleic acid precursors to support their metabolism and growth
B.Sc. Microbiology IV Bacteriology Unit 4.1 Bacterial GrowthRai University
This document discusses bacterial growth and the requirements for bacterial growth. It covers the following key points:
1. Bacterial growth occurs through binary fission where a parent cell divides into two identical daughter cells. Exponential growth occurs when each new cell divides.
2. Bacteria require nutrients like carbon, nitrogen, sulfur, phosphorus and micronutrients for growth. Carbon sources include CO2, organic molecules, and reduced inorganic molecules. Nitrogen sources include amino acids, ammonia, nitrates and nitrogen gas.
3. In addition to macro/micronutrients, some bacteria also require small amounts of organic growth factors like vitamins, amino acids and nucleic acid precursors to support their metabolism.
1) The document discusses microbial growth and culture. It defines microbial growth as the asexual reproduction of bacteria through binary fission to produce two daughter cells identical to the original.
2) Bacterial culture is described as multiplying microbes by letting them reproduce in a controlled laboratory environment with a predetermined culture medium.
3) Four phases of microbial growth are outlined: lag phase, log/exponential phase, stationary phase, and death phase. The lag phase involves only cell size increase while the log phase enables maximum growth and reproduction through binary fission. In stationary phase, cell division and death are equal while death phase involves shortage of nutrients and accumulation of toxins leading to cell death.
This document discusses various topics related to bacterial growth, including the different phases of bacterial growth (lag, log, stationary, death), factors that affect growth, and different types of bacterial growth (diauxic, synchronous, continuous). It provides details on each growth phase and explains that bacteria must be in a suitable environment to grow. The intrinsic and extrinsic factors that influence growth are listed. Diauxic, synchronous, and continuous growth are also summarized, along with details on turbidostat and chemosat methods for continuous growth.
Similar to bacteria-growthcurveisolationandpreservation-210101092212.pdf (20)
How to Build a Module in Odoo 17 Using the Scaffold MethodCeline George
Odoo provides an option for creating a module by using a single line command. By using this command the user can make a whole structure of a module. It is very easy for a beginner to make a module. There is no need to make each file manually. This slide will show how to create a module using the scaffold method.
Strategies for Effective Upskilling is a presentation by Chinwendu Peace in a Your Skill Boost Masterclass organisation by the Excellence Foundation for South Sudan on 08th and 09th June 2024 from 1 PM to 3 PM on each day.
ISO/IEC 27001, ISO/IEC 42001, and GDPR: Best Practices for Implementation and...PECB
Denis is a dynamic and results-driven Chief Information Officer (CIO) with a distinguished career spanning information systems analysis and technical project management. With a proven track record of spearheading the design and delivery of cutting-edge Information Management solutions, he has consistently elevated business operations, streamlined reporting functions, and maximized process efficiency.
Certified as an ISO/IEC 27001: Information Security Management Systems (ISMS) Lead Implementer, Data Protection Officer, and Cyber Risks Analyst, Denis brings a heightened focus on data security, privacy, and cyber resilience to every endeavor.
His expertise extends across a diverse spectrum of reporting, database, and web development applications, underpinned by an exceptional grasp of data storage and virtualization technologies. His proficiency in application testing, database administration, and data cleansing ensures seamless execution of complex projects.
What sets Denis apart is his comprehensive understanding of Business and Systems Analysis technologies, honed through involvement in all phases of the Software Development Lifecycle (SDLC). From meticulous requirements gathering to precise analysis, innovative design, rigorous development, thorough testing, and successful implementation, he has consistently delivered exceptional results.
Throughout his career, he has taken on multifaceted roles, from leading technical project management teams to owning solutions that drive operational excellence. His conscientious and proactive approach is unwavering, whether he is working independently or collaboratively within a team. His ability to connect with colleagues on a personal level underscores his commitment to fostering a harmonious and productive workplace environment.
Date: May 29, 2024
Tags: Information Security, ISO/IEC 27001, ISO/IEC 42001, Artificial Intelligence, GDPR
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বাংলাদেশের অর্থনৈতিক সমীক্ষা ২০২৪ [Bangladesh Economic Review 2024 Bangla.pdf] কম্পিউটার , ট্যাব ও স্মার্ট ফোন ভার্সন সহ সম্পূর্ণ বাংলা ই-বুক বা pdf বই " সুচিপত্র ...বুকমার্ক মেনু 🔖 ও হাইপার লিংক মেনু 📝👆 যুক্ত ..
আমাদের সবার জন্য খুব খুব গুরুত্বপূর্ণ একটি বই ..বিসিএস, ব্যাংক, ইউনিভার্সিটি ভর্তি ও যে কোন প্রতিযোগিতা মূলক পরীক্ষার জন্য এর খুব ইম্পরট্যান্ট একটি বিষয় ...তাছাড়া বাংলাদেশের সাম্প্রতিক যে কোন ডাটা বা তথ্য এই বইতে পাবেন ...
তাই একজন নাগরিক হিসাবে এই তথ্য গুলো আপনার জানা প্রয়োজন ...।
বিসিএস ও ব্যাংক এর লিখিত পরীক্ষা ...+এছাড়া মাধ্যমিক ও উচ্চমাধ্যমিকের স্টুডেন্টদের জন্য অনেক কাজে আসবে ...
This presentation includes basic of PCOS their pathology and treatment and also Ayurveda correlation of PCOS and Ayurvedic line of treatment mentioned in classics.
A workshop hosted by the South African Journal of Science aimed at postgraduate students and early career researchers with little or no experience in writing and publishing journal articles.
How to Manage Your Lost Opportunities in Odoo 17 CRMCeline George
Odoo 17 CRM allows us to track why we lose sales opportunities with "Lost Reasons." This helps analyze our sales process and identify areas for improvement. Here's how to configure lost reasons in Odoo 17 CRM
This presentation was provided by Steph Pollock of The American Psychological Association’s Journals Program, and Damita Snow, of The American Society of Civil Engineers (ASCE), for the initial session of NISO's 2024 Training Series "DEIA in the Scholarly Landscape." Session One: 'Setting Expectations: a DEIA Primer,' was held June 6, 2024.
The simplified electron and muon model, Oscillating Spacetime: The Foundation...RitikBhardwaj56
Discover the Simplified Electron and Muon Model: A New Wave-Based Approach to Understanding Particles delves into a groundbreaking theory that presents electrons and muons as rotating soliton waves within oscillating spacetime. Geared towards students, researchers, and science buffs, this book breaks down complex ideas into simple explanations. It covers topics such as electron waves, temporal dynamics, and the implications of this model on particle physics. With clear illustrations and easy-to-follow explanations, readers will gain a new outlook on the universe's fundamental nature.
2. Bacteria divide by binary fission
Alternative means
Budding
Conidiospores (filamentous
bacteria)
Fragmentation
Bacterial Growth
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4. Time required for cell to divide/for population
to double
Average for bacteria is 1-3 hours
E. coli generation time = 20 min
20 generations (7 hours), 1 cell becomes 1
million cells!
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Generation Time
6. Phases of Bacterial Growth Curve
Phase I: Lag Phase
(Initial Adjustment Phase)
Phase II: Phase of increasing Growth Rate
(1st Transition Phase)
Phase III: Logarithmic Phase
(Exponential Growth Phase)
Phase IV: Phase of Decreasing Growth Rate
(2nd Transition Phase)
Phase V: Stationary Phase
Phase VI: Phase of Increasing Death Rate
(3rd Transition Phase)
Phase VII: Logarithmic Death Phase
(Exponential Death Phase)
Phase VIII: Survival Phase
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7. Phase I: Lag Phase
(Initial Adjustment Phase)
Phase in which there is no change in bacterial count in
initial 2-4 hours after inoculation is called as lag phase.
In this phase bacterial cell adjust with the new environment
and prepares new enzymes in response to new medium.
Phases of Bacterial Growth Curve
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8. Phase II: Phase of increasing Growth Rate
(1st Transition Phase)
In this phase some bacterial cells starts multiplying,
hence there will be slight increase in bacterial count.
At the end of this phase all cells will be in rapid
multiplication stage
Phases of Bacterial Growth Curve
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9. Phase III: Logarithmic Phase
(Exponential Growth Phase)
In this phase bacterial cell is in most active condition.
Nutrients are abundent and metabolites are very less
hence bacterial cells multiply in exponential manner.
This phase is desired for production of microbial
products
Bacterial cell is most sensitive to drugs and radiation
during this period
Phases of Bacterial Growth Curve
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10. Phase IV: Phase of Decreasing Growth Rate
(2nd Transition Phase)
At the end of Log Phase there is depletion of nutrients
and accumulation of toxic metabolites.
Due to this cells start to die and decline in viable
count takes place.
Since many cells are actively multiplying, sudden
decrease will not take place.
Phases of Bacterial Growth Curve
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11. Phase V: Stationary Phase
The "stationary phase" is due to a growth-limiting factor; this is
mostly depletion of a nutrient, and/or the formation of
inhibitory products such as organic acids.
Stationary phase results from a situation in which growth rate
and death rate have the same values
(newly formed cells per time = dying cells per time)
Phases of Bacterial Growth Curve
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12. Phase VI: Phase of Increasing Death Rate
(3rd Transition Phase)
At the end of stationary phase, proportion of dying
cells will increase than the no. of cells multiplying.
This results in third transition phase: Phase of
increasing death rate.
This is due to very much accumulation of toxic
compounds.
Phases of Bacterial Growth Curve
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13. Phase VII: Logarithmic Death Phase
(Exponential Death Phase)
Bacteria run out of nutrients and die although number of cells
remain constant.
The decline phase is brought by exhaution of nutrients,
accumulation of toxic products and autolytic enzymes.
There will be exponential death occurring in this phase and
viable cell count will go on reducing drastically.
Phases of Bacterial Growth Curve
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14. Phase VIII: Survival Phase
Sometimes a small numbers of survivors may persist for
month even after death of majority of cells these few surviving
cells probably grow at expence of nutrients released.
The reason behind this may be
Mutation: At starving condition cells get mutated to take
available substances as their nutrient.
Spore Formation: The bacterial cells get converted into their
dormant form i.e. Spores.
Phases of Bacterial Growth Curve
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15. Growth of bacteria is affected by many factors such as
Nutrition concentration
Temperature
Gaseous concentration
pH
Ions and salt concentration
Available water
Factors affecting Bacterial Growth
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16. Diauxic growth is any cell growth characterized by
cellular growth in two phases
This is illustrated with a diauxic growth curve
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Diauxic Phenomenon
17. In this phenomenon the preferred sugar is consumed first,
which leads to rapid growth, followed by a lag phase.
During the lag phase the cellular machinery used to
metabolize the second sugar is activated
Subsequently the second sugar is metabolized
Remaining steps will be same as that of bacterial growth
curve.
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Diauxic Phenomenon
18. Bacteria grow nonsynchronously in
ordinary culture medium, i.e at any
moment cells are present in different
stage of growth cycle.
When all bacterial cells in culture
medium divide simultaneously growth
thus obtained is known as synchronous
growth.
Such growth is required for studing the
sequence of event occuring in single cell
like studies on DNA synthesis or
susceptibility of cell to lethal agent
Synchronous Bacterial Growth
Culture
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19. External conditions can be changed, so as to arrest growth of
all cells in the culture, and then changed again to resume
growth. The newly growing cells are now all starting to grow at
the same stage, and they are synchronized. e.g.
for photosynthetic cells, light can be eliminated for several
hours and then re-introduced.
Eliminate an essential nutrient from the growth medium and
later re-introduce it.[5]
Cell growth can also be arrested using chemical growth
inhibitors.
e.g. Nocodazole, for example, has been used in biological
research for synchronization.
Physical Separation based on their density or size, for
instance. This can be achieved using centrifugation (for
density) or filtration (for size).
Methods for Synchronous Bacterial
Growth
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20. Helmstetter-Cummings technique
In this technique, a bacterial culture is filtered through a
membrane. Most bacteria pass through, but some remain
bound to the membrane. Fresh medium is then applied to the
membrane and the bound bacteria start to grow. Newborn
bacteria that detach from the membrane are now all at the
same stage of growth; they are collected in a flask that now
harbors a synchronous culture
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Methods for Synchronous Bacterial
Growth
21. Continuous Bacterial Growth Culture
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Continuous bacterial growth culture aims to keep a
culture growing indefinitely.
In this the bacterial culture is maintained in the
exponential growth phase.
Continuous culture is important in industrial processes
that harvest the primary metabolites.
This can be achieved by:
Fresh nutrients are continually supplied
Accumulated cells and waste products are removed at
the same rate
Conditions such as temperature and pH are kept at their
optimum values
22. Methods for Continuous Bacterial
Growth
Chemostat System
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23. A turbidostat dynamically
adjusts the flow rate (and
therefore the dilution rate) to
make the turbidity constant.
At steady state, operation of
both the chemostat and
turbidostat are identical.
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Continuous Bacterial Growth
Turbidostat System
24. Pure culture : containing a single species of
organism.
Isolation of Bacterial Pure Culture
A pure culture is usually derived from a mixed
culture (one containing many species) by
transferring a small sample into new, sterile growth
medium in such a manner as to disperse the
individual cells across the medium surface or by
thinning the sample many times before inoculating
the new medium
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Isolation of Bacterial Pure Culture
25. Importance of Isolation of Bacterial Pure Culture
Once purified, the isolated species can then be cultivated
with the knowledge that only the desired microorganism
is being grown.
A pure culture can be correctly identified for accurate
studying and testing, and diagnosis in a clinical
environment.
Testing/experimenting with a pure culture ensures that the
same results can be achieved regardless of how many
time the test is repeated.
Pure culture spontaneous mutation rate is low.
Pure culture clone is 99.999% identical.
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Isolation of Bacterial Pure Culture
26. Cultures composed of cells arising from a single progenitor
Progenitor is termed a CFU (Colony Forming Unit)
Aseptic technique prevents contamination of sterile
substances or objects
Techniques For isolation
Streak plate method
Pour plate method
Spread plate method
Roll tube method
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College
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Isolation of Bacterial Pure Culture
27. Special Methods of Isolation of Bacteria
Single Cell Isolation
Capillary Pipette Method
Micromanipulator Method
Enrichment Culture Method
The enrichment culture strategy provides a
specially designed cultural environment by
incorporating a specific nutrient in the medium and
by modifying the physical conditions of the
incubator
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College
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Isolation of Bacterial Pure Culture
28. Streak plate method
Streaking is the process of spreading the microbial
culture with an inoculating needle on the surface of the
media.
Sterilize the inoculating needle by flame to make red
hot and allow it to cool for 30 seconds.
Thesample is streaked in such a way to provide series
of dilution.
purpose-thin out innoculum to get seprate colonies.
Subculturing can be done by streaking well isolated
colonies from streak plate to new plate.
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Isolation of Bacterial Pure Culture
29. Streak plate method
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Isolation of Bacterial Pure Culture
I
n
c
u
b
a
ti
o
n
31. Pour plate method
The bacterial culture and liquid agar medium are
mixed together.
After mixing the medium, the medium containing
the culture poured into sterilized
Petri dishes ( Petri plates), allowed solidifying and
then incubated.
After incubation colonies appear on the surface.
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Isolation of Bacterial Pure Culture
33. Disadvantages of pour plate technique:
Microorganism trapped beneath the surface of medium
hence surface as well as subsurface Colonies are
developed which makes the difficulties in counting the
bacterial colony.
Tedious and time consuming method, microbes are
subjected to heat shock because liquid
Medium maintained at 45℃., hence is unsuitable for
psychrophile
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Isolation of Bacterial Pure Culture
34. Spread plate method
This is the best method to isolate thepure colonies.
In this technique, the culture is not mixed with the agar
medium. Instead it is mixed with
normal saline and serially diluted.
0.1 ml of sample taken from diluted mixture, which is
placed on the surface of the agar plate
and spread evenly over the surface by using L shaped
glass rod called spreader.
Incubate the plates
After incubation, colonies are observed on the agar
surface.
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Isolation of Bacterial Pure Culture
36. Roll tube method
2ml nutrient agar melted, cooled to 50 centigrade, with 0.02 ml
pipette one drop of culture is added to test tube.
Tubes rolled in horizontal position under cold water tap to
make uniform agar layer, incubated and colonies counted.
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Isolation of Bacterial Pure Culture
37. Micromanipulator method
Micromanipulators have been built, which permit
one to pick out a single cell from a mixed
culture. This instrument is used in conjunction with
a microscope to pick a single cell
(particularly bacterial cell) from a hanging drop
preparation.
The single cell of microbe sucked into micropipette
and transferred to large amount of sterile medium.
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Isolation of Bacterial Pure Culture
38. ADVANTAGES OF MICROMANIPULATOR METHOD
The advantages of this method are that one can be
reasonably sure that the cultures come
from a single cell and one can obtain strains with in the
species.
DISADVANTAGES
The disadvantages are that the equipment is expensive, its
manipulation is very tedious, and it requires a skilled person.
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Isolation of Bacterial Pure Culture
39. Enrichment Culture Method
The enrichment culture strategy provides a specially
designed cultural environment by incorporating a
specific nutrient in the medium and by modifying the
physical conditions of the incubator
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Isolation of Bacterial Pure Culture
40. Preservation
To maintain pure culture for extended periods in a viable
conditions, without any genetic change is referred as
Preservation.
The aim of preservation is to stop the cell division at a
particular stage i.e. to stop microbial growth or at least
lower the growth rate.
Due to this toxic chemicals are not accumulated and
hence viability of microorganisms is not affected.
Objectives of preservation
To maintain isolated pure cultures for extended periods
in a viable conditions.
To avoid the contamination.
To restrict genetic change (Mutation)
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Preservation of Bacterial Pure Culture
41. Method of Preservation
Short Term Methods
Periodic transfer to fresh media (Subculturing)
Preservation of bacteria using glycerol
Storage by refrigeration
Long Term Methods
Mineral oil or liquid paraffin storage
Storage in saline suspension
Storage in sterile soil
Lyophilization (freeze–drying)
Cryopreservation
Stored in silica gel
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Preservation of Bacterial Pure Culture
42. Periodic transfer to fresh media (Subculturing)
The bacterial culture can be stored for longer time by
addition of bacterial cells in fresh medium periodically
Many of the more common microbes remain viable for
several weeks or months on a medium like Nutrient agar.
It is an advantageous as it is a simple method and any
special apparatus are not required.
It is easy to recover the culture.
The transfer has the disadvantage of failing to prevent
changes in the characteristics of a strain due to
development of variants and mutants and risk of
contamination is also more in this process.
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Preservation of Bacterial Pure Culture
44. Preservation of bacteria using glycerol
Bacteria can be frozen using 15% glycerol.
The glycerol is diluted to 30% and an equal amount of
glycerol and culture broth are mixed, dispensed into
tubes, and then frozen at -10˚ C.
The viability of organisms varied such as Escherichia
coli, Diplococcus pneumonia etc. viable for 5 months,
Haemophilus influnzae viable for 4 months,
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Preservation of Bacterial Pure Culture
45. Storage by refrigeration
Pure cultures can be successfully stored at 0-4°C either
in refrigerators or incold-rooms.
At this temperature range the metabolic activities of
microbes slows down greatly and only small quantity of
nutrients will be utilized.
This method is applied for short duration (2-3 weeks for
bacteria and 3-4months for fungi) because the metabolic
activities of the microorganisms are greatly slowed down
but not stopped.
Thus their growth continue slowly, nutrients are utilized
and waste products released in medium.
This results in finally the death of the microorganisms
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Preservation of Bacterial Pure Culture
46. Mineral oil or liquid paraffin storage
In this method sterile liquid paraffin is
poured over the slant culture of
microbes and stored upright at room
temperature.
Where as cultures can also be
maintained by covering agar slants by
sterile mineral oil which is stored at
room temperature or preferably at 0-
5°C.
It limit the oxygen access that reduces
the microorganism’s metabolism and
growth, as well as to cell drying during
preservation.
The preservation period for bacteria
from the genera Azotobacter and
Mycobacterium is from 7-10 years, for
Bacillus it is 8-12 years.
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Preservation of Bacterial Pure Culture
47. Storage in saline suspension
Bacterial culture is preserved in 1% salt concentration in
screw caped tubes to prevent evaporation.
The tubes are stored in room temperature.
Whenever needed the transfer is made on Agar Slant.
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Preservation of Bacterial Pure Culture
48. Storage in sterile soil
Soil storage involves inoculation of 1ml of spore
suspension into soil (autoclaved twice) and incubating at
room temperature for 5-10 days.
The initial growth period allows the fungus to use the
available moisture and gradually to become dormant.
The bottles are then stored at refrigerator.
Viability of organisms found around 70- 80 years
It is mainly applied for the preservation of sporulating
microorganisms
Fusarium, Penicillium, Alternaria, Rhizopus, Bacillus,
Aspergillus, Penicillium, etc. proved successful for store
in sterile soil.
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Preservation of Bacterial Pure Culture
49. Lyophilization (freeze–drying)
It is a vacuum sublimation technique.
Freeze drying products are hygroscopic and must be protected
from moisture during storage.
By freezing the cells in a medium that contain a lyoprotectant
(usually sucrose) and then pulling the water out using vacuum
(sublimation), cells can be effectively preserved.
Freezing must be very rapid, with the temperature lowered to
well below 0˚C (as such -20˚C).
Lyophilized cultures are stored in the dark 4˚C in refrigerators.
Many microbes preserved by this method have remained
viable and unchanged in their characteristic more than 20
years.
It is very advantageous as only minimal storage space is
required to preserve.
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Preservation of Bacterial Pure Culture
51. Procedure of Lyophilization
In this process, a dense cell suspension is placed in
small vials and frozen at -60 to -70°C.
The vial are immediately connected to a high vacuum
line.
The ice present in the frozen suspension
evaporates(sublime) under the vacuum.
This results in dehydration of bacterial cell and their
metabolic activities are stopped; as a result, the
microbes go into dormant state and retain viability for
years.
The vials are then sealed off under a vacuum and stored
in the dark at 4°C in refrigerators.
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Preservation of Bacterial Pure Culture
52. Cryopreservation
Cryopreservation (i.e., freezing in liquid nitrogen at -196°C
or in the gas phase above the liquid nitrogen at -150°C)
helps survival of pure cultures for long storage times.
In this method, the microorganisms of culture are rapidly
frozen in liquid nitrogen at -196°C in the presence of
stabilizing agents such as glycerol or Dimethyl Sulfoxide
(DMSO) that prevent the cell damage due to formation of
ice crystals and promote cell survival.
This liquid nitrogen method has been successful with many
species that cannot be preserved by lyophilization and
most species can remain viable under these conditions for
10 to 30 years without undergoing change in thei
characteristics, however this method is expensive.
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Preservation of Bacterial Pure Culture
53. Stored in silica gel
Microbes can be stored in silica gel powder at low
temperature for a period 1- 2 years.
The basic principle in this technique is quick desiccation
at low temperature, which allows the cell to remain
viable for a long period of time.
Some of the species which are preserved on anhydrous
silica gel are such as Saccharomyces cerevisiae,
Aspergillus nidulans, Pseudomonas denitrificans,
Escherichia coli etc.
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Preservation of Bacterial Pure Culture