The document discusses various metabolic pathways in plants including primary and secondary metabolites. It describes the shikimic acid pathway and its role in synthesizing aromatic amino acids. The acetate/mevalonate pathway and its role in terpenoid biosynthesis is also covered. Various techniques used to study these pathways are outlined, including the use of radioactive isotopes as tracers to investigate biosynthesis through precursor-product relationships. The summary focuses on the key metabolic pathways and tracer techniques discussed in the document.
According to the PCI Syllabus ,B Pharm V Sem Sub : Pharmacognosy and Phytochemistry II
It contains the general introduction of metabolic Pathways ,Metabolites and How primary metabolites are linked with secondary metabolites
Commonly known as its anionic form shikimate, is a cyclohexene, a cyclitol and a cyclohexanecarboxylic acid.
It is an important biochemical metabolite in plants and microorganisms.
Its name comes from the Japanese flower shikimi the Japanese star anise, Illicium anisatum), from which it was first isolated in 1885 by Johan Fredrik Eykman.
The elucidation of its structure was made nearly 50 years later.
Shikimic acid is also the glycoside part of some hydrolysable tannins.
The shikimate pathway is a seven step metabolic route used by bacteria, fungi, algae, parasites, and plants for the biosynthesis of aromatic amino acids (phenylalanine, tyrosine, and tryptophan).
This pathway is not found in animals; therefore, phenylalanine and tryptophan represent essential amino acids that must be obtained from the animal's diet
Animals can synthesize tyrosine from phenylalanine, and therefore is not an essential amino acid except for individuals unable to hydroxylate phenylalanine to tyrosine).
According to the PCI Syllabus ,B Pharm V Sem Sub : Pharmacognosy and Phytochemistry II
It contains the general introduction of metabolic Pathways ,Metabolites and How primary metabolites are linked with secondary metabolites
Commonly known as its anionic form shikimate, is a cyclohexene, a cyclitol and a cyclohexanecarboxylic acid.
It is an important biochemical metabolite in plants and microorganisms.
Its name comes from the Japanese flower shikimi the Japanese star anise, Illicium anisatum), from which it was first isolated in 1885 by Johan Fredrik Eykman.
The elucidation of its structure was made nearly 50 years later.
Shikimic acid is also the glycoside part of some hydrolysable tannins.
The shikimate pathway is a seven step metabolic route used by bacteria, fungi, algae, parasites, and plants for the biosynthesis of aromatic amino acids (phenylalanine, tyrosine, and tryptophan).
This pathway is not found in animals; therefore, phenylalanine and tryptophan represent essential amino acids that must be obtained from the animal's diet
Animals can synthesize tyrosine from phenylalanine, and therefore is not an essential amino acid except for individuals unable to hydroxylate phenylalanine to tyrosine).
Use of microbes in industry. Production of enzymes-General consideration-Amyl...Steffi Thomas
Industrial uses of microbes, properties of useful industrial microbes, various industrial products, production of enzymes-general consideration-amylase, catalase, peroxidase, lipase, protease, penicillinase, procedure for culturing bacteria and inoculum preparation, submerged fermentation and solid state fermentation, uses of different enzymes
The shikimate pathway was discovered as the biosynthetic route to the aromatic amino acids phenylalanine, tyrosine, and tryptophan.
This pathway has been found only in microorganisms and plants. Phenylalanine and tryptophan are essential components of animal diets, and animals synthesize tyrosine in a single step from phenylalanine.
Biosynthesis and pharmaceutical applications of alkaloids [autosaved]JasmineJuliet
Alkaloids definition, History of Biosynthesis of alkaloids, Alkaloids application in pharmaceutical field, Biological activity of alkaloids, Alkaloids have different pharmaceutical property their names and their uses in pharmaceutical field.
Flavonoids classification, isolation and identificationMona Ismail
Flavonoids are groups of polyphenolic compounds which are found in fruits, flowers, seeds & vegetable.
(named from the Latin word flavus meaning yellow, their colour in nature)
Enzyme definition, Enzyme immobilization introduction , Enzyme immobilization definition, Explanation about support/ matrix, Examples about immobilized enzymes and their product, Advantages of immobilization, Applications of immobilization, Methods of immobilization in different categories like Adsorption method, Covalent bonding method, Entrapment method, Co polymerization /Cross linking method, Encapsulation method, Applications of immobilized enzymes, Diagrammatic explanation about methods of immobilization.
Pharmacognosy and phytochemistry- II/ semester V/ Unit I/Basic metabolic pathway/ Primary metabolites/ secondary metabolites/ formation secondary metabolites/ Formation of amino acid / role of enzyme/ role of coenzyme
Use of microbes in industry. Production of enzymes-General consideration-Amyl...Steffi Thomas
Industrial uses of microbes, properties of useful industrial microbes, various industrial products, production of enzymes-general consideration-amylase, catalase, peroxidase, lipase, protease, penicillinase, procedure for culturing bacteria and inoculum preparation, submerged fermentation and solid state fermentation, uses of different enzymes
The shikimate pathway was discovered as the biosynthetic route to the aromatic amino acids phenylalanine, tyrosine, and tryptophan.
This pathway has been found only in microorganisms and plants. Phenylalanine and tryptophan are essential components of animal diets, and animals synthesize tyrosine in a single step from phenylalanine.
Biosynthesis and pharmaceutical applications of alkaloids [autosaved]JasmineJuliet
Alkaloids definition, History of Biosynthesis of alkaloids, Alkaloids application in pharmaceutical field, Biological activity of alkaloids, Alkaloids have different pharmaceutical property their names and their uses in pharmaceutical field.
Flavonoids classification, isolation and identificationMona Ismail
Flavonoids are groups of polyphenolic compounds which are found in fruits, flowers, seeds & vegetable.
(named from the Latin word flavus meaning yellow, their colour in nature)
Enzyme definition, Enzyme immobilization introduction , Enzyme immobilization definition, Explanation about support/ matrix, Examples about immobilized enzymes and their product, Advantages of immobilization, Applications of immobilization, Methods of immobilization in different categories like Adsorption method, Covalent bonding method, Entrapment method, Co polymerization /Cross linking method, Encapsulation method, Applications of immobilized enzymes, Diagrammatic explanation about methods of immobilization.
Pharmacognosy and phytochemistry- II/ semester V/ Unit I/Basic metabolic pathway/ Primary metabolites/ secondary metabolites/ formation secondary metabolites/ Formation of amino acid / role of enzyme/ role of coenzyme
Metabolites, Secondary metabolites are derived from primary metabolites, Why secondary metabolites, Phenolics, Terpenoids, Alkaloids, Special nitrogen metabolites, Cuticular compounds .The major classes of these found in plants
PPT presentation is on HMP Shunt and regulations of microbial metabolism.
The Hexose Monophosphate Pathway also called the Phosphogluconate Pathway and the Pentose Phosphate Pathway.
This pathway parallel to glycolysis.
This pathway is important for formation of NADPH and Pentose as well as ribose-5-phosphate.
Physiology and chemistry of skin and pigmentation, hairs, scalp, lips and nail, Cleansing cream, Lotions, Face powders, Face packs, Lipsticks, Bath products, soaps and baby product,
Preparation and standardization of the following : Tonic, Bleaches, Dentifrices and Mouth washes & Tooth Pastes, Cosmetics for Nails.
Biological screening of herbal drugs: Introduction and Need for
Phyto-Pharmacological Screening, New Strategies for evaluating
Natural Products, In vitro evaluation techniques for Antioxidants, Antimicrobial and Anticancer drugs. In vivo evaluation techniques
for Anti-inflammatory, Antiulcer, Anticancer, Wound healing, Antidiabetic, Hepatoprotective, Cardio protective, Diuretics and
Antifertility, Toxicity studies as per OECD guidelines
Ethnobotany and Ethnopharmacology:
Ethnobotany in herbal drug evaluation,
Impact of Ethnobotany in traditional medicine,
New development in herbals,
Bio-prospecting tools for drug discovery,
Role of Ethnopharmacology in drug evaluation,
Reverse Pharmacology.
Adulteration and Deterioration: Introduction, Types of
Adulteration/ Substitution of Herbal drugs, Causes and Measures
of Adulteration, Sampling Procedures, Determination of Foreign
Matter, DNA Finger printing techniques in identification of drugs of
natural origin, detection of heavy metals, pesticide residues, phytotoxin, microbial contamination in herbs and their
formulations.
Herbal/natural cosmetics, Classification &
Economic aspects. Regulatory Provisions relation to manufacture of cosmetics: -
License, GMP, offences & Penalties, Import & Export of
Herbal/natural cosmetics, Industries involved in the production of Herbal/natural cosmetics.
Toxicity and Regulations: Herbals vs
Conventional drugs, Efficacy of Herbal medicine products, Validation of herbal therapies, Pharmacodynamic and
Pharmacokinetic issues.
Content:
Pharmacovigilance of drugs of natural origin:
WHO and AYUSH guidelines for safety monitoring of natural medicine, Spontaneous reporting schemes for bio drug adverse reactions, bio drug-drug and bio drug-food interactions with suitable examples.
Patents: Indian and international patent laws, proposed
amendments as applicable to herbal/natural products and
process. Geographical indication, Copyright, Patentable subject
maters, novelty, non obviousness, utility, enablement and best
mode, procedure for Indian patent filing, patent processing, grant
of patents, rights of patents, cases of patents, opposition and
revocation of patents, patent search and literature, Controllers of
patents.
Monographs of herbal drugs: General parameters of
monographs of herbal drugs and comparative study in IP, USP,
Ayurvedic Pharmacopoeia, Siddha and Unani Pharmacopoeia,
American herbal pharmacopoeia, British herbal pharmacopoeia,
WHO guidelines in quality assessment of herbal drugs.
Nutraceuticals: Current trends and future scope, Inorganic
mineral supplements, Vitamin supplements, Digestive enzymes,
Dietary fibres, Cereals and grains, Health drinks of natural origin,
Antioxidants, Polyunsaturated fatty acids, Herbs as functional
foods, Formulation and standardization of neutraceuticals,
Regulatory aspects, FSSAI guidelines,
Sources, name of marker
compounds and their chemical nature, medicinal uses and health
benefits of following
i) Spirulina ii) Soya bean iii) Ginseng iv) Garlic v) Broccoli VI)
Green and Herbal Tea vii) Flax seeds viii) Black cohosh ix)
Turmeric.
Unit 2. Regulatory requirements for setting herbal drug industry:
Content: Global marketing management.
Indian and International patent law as applicable herbal drugs and natural products.
Export - Import (EXIM) policy, TRIPS.
Quality assurance in herbal/natural drug products.
Concepts of TQM, GMP, GLP, ISO-9000.
INDUSTRIAL PHARMACOGNOSTICAL TECHNOLOGY
Herbal drug industry: Infrastructure of herbal drug industry
involved in production of standardized extracts and various
dosage forms. Current challenges in upgrading and
modernization of herbal formulations. Entrepreneurship
Development, Project selection, project report, technical
knowledge, Capital venture, plant design, layout and construction.
Pilot plant scale –up techniques, case studies of herbal extracts.
Formulation and production management of herbals.
Marine natural products: General methods of isolation and
purification, Study of Marine toxins, Recent advances in research
in marine drugs, Problems faced in research on marine drugs
such as taxonomical identification, chemical screening and their
solution.
Unit I: Plant Drug Cultivation
General introduction to the importance of
Pharmacognosy in herbal drug industry, Indian Council of
Agricultural Research, Current Good Agricultural Practices,
Current Good Cultivation Practices, Current Good Collection
Practices, Conservation of medicinal plants- Ex-situ and Insitu
conservation of medicinal plants.
Title: Sense of Taste
Presenter: Dr. Faiza, Assistant Professor of Physiology
Qualifications:
MBBS (Best Graduate, AIMC Lahore)
FCPS Physiology
ICMT, CHPE, DHPE (STMU)
MPH (GC University, Faisalabad)
MBA (Virtual University of Pakistan)
Learning Objectives:
Describe the structure and function of taste buds.
Describe the relationship between the taste threshold and taste index of common substances.
Explain the chemical basis and signal transduction of taste perception for each type of primary taste sensation.
Recognize different abnormalities of taste perception and their causes.
Key Topics:
Significance of Taste Sensation:
Differentiation between pleasant and harmful food
Influence on behavior
Selection of food based on metabolic needs
Receptors of Taste:
Taste buds on the tongue
Influence of sense of smell, texture of food, and pain stimulation (e.g., by pepper)
Primary and Secondary Taste Sensations:
Primary taste sensations: Sweet, Sour, Salty, Bitter, Umami
Chemical basis and signal transduction mechanisms for each taste
Taste Threshold and Index:
Taste threshold values for Sweet (sucrose), Salty (NaCl), Sour (HCl), and Bitter (Quinine)
Taste index relationship: Inversely proportional to taste threshold
Taste Blindness:
Inability to taste certain substances, particularly thiourea compounds
Example: Phenylthiocarbamide
Structure and Function of Taste Buds:
Composition: Epithelial cells, Sustentacular/Supporting cells, Taste cells, Basal cells
Features: Taste pores, Taste hairs/microvilli, and Taste nerve fibers
Location of Taste Buds:
Found in papillae of the tongue (Fungiform, Circumvallate, Foliate)
Also present on the palate, tonsillar pillars, epiglottis, and proximal esophagus
Mechanism of Taste Stimulation:
Interaction of taste substances with receptors on microvilli
Signal transduction pathways for Umami, Sweet, Bitter, Sour, and Salty tastes
Taste Sensitivity and Adaptation:
Decrease in sensitivity with age
Rapid adaptation of taste sensation
Role of Saliva in Taste:
Dissolution of tastants to reach receptors
Washing away the stimulus
Taste Preferences and Aversions:
Mechanisms behind taste preference and aversion
Influence of receptors and neural pathways
Impact of Sensory Nerve Damage:
Degeneration of taste buds if the sensory nerve fiber is cut
Abnormalities of Taste Detection:
Conditions: Ageusia, Hypogeusia, Dysgeusia (parageusia)
Causes: Nerve damage, neurological disorders, infections, poor oral hygiene, adverse drug effects, deficiencies, aging, tobacco use, altered neurotransmitter levels
Neurotransmitters and Taste Threshold:
Effects of serotonin (5-HT) and norepinephrine (NE) on taste sensitivity
Supertasters:
25% of the population with heightened sensitivity to taste, especially bitterness
Increased number of fungiform papillae
These simplified slides by Dr. Sidra Arshad present an overview of the non-respiratory functions of the respiratory tract.
Learning objectives:
1. Enlist the non-respiratory functions of the respiratory tract
2. Briefly explain how these functions are carried out
3. Discuss the significance of dead space
4. Differentiate between minute ventilation and alveolar ventilation
5. Describe the cough and sneeze reflexes
Study Resources:
1. Chapter 39, Guyton and Hall Textbook of Medical Physiology, 14th edition
2. Chapter 34, Ganong’s Review of Medical Physiology, 26th edition
3. Chapter 17, Human Physiology by Lauralee Sherwood, 9th edition
4. Non-respiratory functions of the lungs https://academic.oup.com/bjaed/article/13/3/98/278874
Couples presenting to the infertility clinic- Do they really have infertility...Sujoy Dasgupta
Dr Sujoy Dasgupta presented the study on "Couples presenting to the infertility clinic- Do they really have infertility? – The unexplored stories of non-consummation" in the 13th Congress of the Asia Pacific Initiative on Reproduction (ASPIRE 2024) at Manila on 24 May, 2024.
micro teaching on communication m.sc nursing.pdfAnurag Sharma
Microteaching is a unique model of practice teaching. It is a viable instrument for the. desired change in the teaching behavior or the behavior potential which, in specified types of real. classroom situations, tends to facilitate the achievement of specified types of objectives.
- Video recording of this lecture in English language: https://youtu.be/lK81BzxMqdo
- Video recording of this lecture in Arabic language: https://youtu.be/Ve4P0COk9OI
- Link to download the book free: https://nephrotube.blogspot.com/p/nephrotube-nephrology-books.html
- Link to NephroTube website: www.NephroTube.com
- Link to NephroTube social media accounts: https://nephrotube.blogspot.com/p/join-nephrotube-on-social-media.html
The prostate is an exocrine gland of the male mammalian reproductive system
It is a walnut-sized gland that forms part of the male reproductive system and is located in front of the rectum and just below the urinary bladder
Function is to store and secrete a clear, slightly alkaline fluid that constitutes 10-30% of the volume of the seminal fluid that along with the spermatozoa, constitutes semen
A healthy human prostate measures (4cm-vertical, by 3cm-horizontal, 2cm ant-post ).
It surrounds the urethra just below the urinary bladder. It has anterior, median, posterior and two lateral lobes
It’s work is regulated by androgens which are responsible for male sex characteristics
Generalised disease of the prostate due to hormonal derangement which leads to non malignant enlargement of the gland (increase in the number of epithelial cells and stromal tissue)to cause compression of the urethra leading to symptoms (LUTS
Report Back from SGO 2024: What’s the Latest in Cervical Cancer?bkling
Are you curious about what’s new in cervical cancer research or unsure what the findings mean? Join Dr. Emily Ko, a gynecologic oncologist at Penn Medicine, to learn about the latest updates from the Society of Gynecologic Oncology (SGO) 2024 Annual Meeting on Women’s Cancer. Dr. Ko will discuss what the research presented at the conference means for you and answer your questions about the new developments.
Ethanol (CH3CH2OH), or beverage alcohol, is a two-carbon alcohol
that is rapidly distributed in the body and brain. Ethanol alters many
neurochemical systems and has rewarding and addictive properties. It
is the oldest recreational drug and likely contributes to more morbidity,
mortality, and public health costs than all illicit drugs combined. The
5th edition of the Diagnostic and Statistical Manual of Mental Disorders
(DSM-5) integrates alcohol abuse and alcohol dependence into a single
disorder called alcohol use disorder (AUD), with mild, moderate,
and severe subclassifications (American Psychiatric Association, 2013).
In the DSM-5, all types of substance abuse and dependence have been
combined into a single substance use disorder (SUD) on a continuum
from mild to severe. A diagnosis of AUD requires that at least two of
the 11 DSM-5 behaviors be present within a 12-month period (mild
AUD: 2–3 criteria; moderate AUD: 4–5 criteria; severe AUD: 6–11 criteria).
The four main behavioral effects of AUD are impaired control over
drinking, negative social consequences, risky use, and altered physiological
effects (tolerance, withdrawal). This chapter presents an overview
of the prevalence and harmful consequences of AUD in the U.S.,
the systemic nature of the disease, neurocircuitry and stages of AUD,
comorbidities, fetal alcohol spectrum disorders, genetic risk factors, and
pharmacotherapies for AUD.
Title: Sense of Smell
Presenter: Dr. Faiza, Assistant Professor of Physiology
Qualifications:
MBBS (Best Graduate, AIMC Lahore)
FCPS Physiology
ICMT, CHPE, DHPE (STMU)
MPH (GC University, Faisalabad)
MBA (Virtual University of Pakistan)
Learning Objectives:
Describe the primary categories of smells and the concept of odor blindness.
Explain the structure and location of the olfactory membrane and mucosa, including the types and roles of cells involved in olfaction.
Describe the pathway and mechanisms of olfactory signal transmission from the olfactory receptors to the brain.
Illustrate the biochemical cascade triggered by odorant binding to olfactory receptors, including the role of G-proteins and second messengers in generating an action potential.
Identify different types of olfactory disorders such as anosmia, hyposmia, hyperosmia, and dysosmia, including their potential causes.
Key Topics:
Olfactory Genes:
3% of the human genome accounts for olfactory genes.
400 genes for odorant receptors.
Olfactory Membrane:
Located in the superior part of the nasal cavity.
Medially: Folds downward along the superior septum.
Laterally: Folds over the superior turbinate and upper surface of the middle turbinate.
Total surface area: 5-10 square centimeters.
Olfactory Mucosa:
Olfactory Cells: Bipolar nerve cells derived from the CNS (100 million), with 4-25 olfactory cilia per cell.
Sustentacular Cells: Produce mucus and maintain ionic and molecular environment.
Basal Cells: Replace worn-out olfactory cells with an average lifespan of 1-2 months.
Bowman’s Gland: Secretes mucus.
Stimulation of Olfactory Cells:
Odorant dissolves in mucus and attaches to receptors on olfactory cilia.
Involves a cascade effect through G-proteins and second messengers, leading to depolarization and action potential generation in the olfactory nerve.
Quality of a Good Odorant:
Small (3-20 Carbon atoms), volatile, water-soluble, and lipid-soluble.
Facilitated by odorant-binding proteins in mucus.
Membrane Potential and Action Potential:
Resting membrane potential: -55mV.
Action potential frequency in the olfactory nerve increases with odorant strength.
Adaptation Towards the Sense of Smell:
Rapid adaptation within the first second, with further slow adaptation.
Psychological adaptation greater than receptor adaptation, involving feedback inhibition from the central nervous system.
Primary Sensations of Smell:
Camphoraceous, Musky, Floral, Pepperminty, Ethereal, Pungent, Putrid.
Odor Detection Threshold:
Examples: Hydrogen sulfide (0.0005 ppm), Methyl-mercaptan (0.002 ppm).
Some toxic substances are odorless at lethal concentrations.
Characteristics of Smell:
Odor blindness for single substances due to lack of appropriate receptor protein.
Behavioral and emotional influences of smell.
Transmission of Olfactory Signals:
From olfactory cells to glomeruli in the olfactory bulb, involving lateral inhibition.
Primitive, less old, and new olfactory systems with different path
2. Introduction –
Overview of Basic metabolic pathways
Role of Enzymes
Role of Co-enzymes
Shikmic acid pathway
Role of shikmic acid pathway
Acatate pathway
Amino acid pathway
Utilization of Radioactive isotopes in the
investigation of biogenetic disease.
3. Metabolic pathways:
Metabolic pathway comprises of series of
chemical reactions which occurs inside the
cells. The reactants, products, and
intermediates which are formed as a result of
these enzymatic reactions are called as
Metabolites. These enzymes typically need
dietary minerals, vitamins, and different
cofactors to perform.
There are two types of metabolites-
1. Primary plant metabolites.
2. Secondary plant metabolites.
4. 1. Primary plant metabolites- These are considered as
basic plant constituents. They are simple in structure
and they do not have biological and pharmacological
activity associated with them. Primary metabolites
are utilized by plants for building up their body and
responsible for physiological functioning of the plant
body. eg. Starch, Cellulose, Chlorophyll, Calcium
oxalate crystals etc.
Degradation of carbohydrates and sugars which
release energy from the organic compounds by
oxidative reactions.
Oxidation of fatty acid from fats by β- oxidation also
provides energy.
Proteins taken via diet provide amino acid most
organism can synthesize only proportion of amino
acid they actually required for protein synthesis those
not synthesized they are called as essential amino
acid obtained from external sources.
5. Secondary metabolites are not essential for growth they have wide
range of chemical structures and biological activity. they are derived by
unique biosynthetic Pathways from primary metabolites and
intermediates
That are not necessary for growth and Reproduction of organism but
which can be demonstrated genetically ,physiologically and
biochemicaliy.
These are also known as active constituents. The quantity of active
constituents that is a secondary plant metabolites determines the
intrinsic important role in the process of biosynthesis.
Fatty acids fats
photosynthesis +carbon dioxide starch
glucose
Fructose
Erythrose Glycerate
Amino acid
7. The majority of secondary metabolites belong to
one of the number of families each of which
have particular structural characteristic arising
from the way in which they are built up in nature
that is also called as the biosynthesis.
The classes of secondary metabolites are:
Polyketides and fatty acids
Terpenoids and steroids
Phenyl propanoyl
Alkaloids
Others such as a specialised amino acids and
carbohydrates
8. Enzyme plays a vital role as a similar to catalyst in monitoring
various cellular activity enzymes are important for both plant
and animals.
Enzymes are very delicate sensitive and thermolabile in
nature.
In the absence of enzyme it is impossible to carry out
reactions in the body, chemically enzymes are proteins in
nature these are colloidal catalyst which helps to increase the
speed of biochemical reactions.
Sometimes ; only the speed of reaction is affected but it
becomes impossible for a plants to carry out the reaction in
their body.
They are very sensitive and active on specific temperature
and pH of the medium in which the reaction is carried out the
enzymes can be destroyed and inactivated due to the
following reasons
1. due to excessive heat
2. due to excessive moisture
10. Co-Enzymes are the organic molecules which are present in
very small amounts their presence in highly important for normal
functioning of enzyme. It is observed that due to the absence of
the some co-enzymes, sometime enzymes are not actively
showing their potency.
eg. Uridine phophate and Adenosine phosphate contains
Nucleotide.
Some Co-enzymes in plant body-
Uridine triphosphate
Thiamine
Pyridixine
Nicotinamide
Uridine diphosphate
Riboflavin
Flavin. Etc.
11.
12. Introduction to Shikimic acid pathway-
Shikimic acid is also known as a Sikhmate in its ionic
form. structurally it is a cyclohexane,a cyclitol and a
cyclohexane carboxylic acid.
It is an important biochemical metabolite in plants and
microorganisms.
Its name is derived from Japanese plant Shikimi
(Illicium anisatum) Shikimic acid is a first isolated from
this plant in 1885 by Johan fendrik Eykman.
This pathway is not found in animals.
This pathway utilized by bacteria, fungi, algae,
parasites and plants for biosynthesis of aromatic amino
acids like phenylalanine, tyrosine and tryptophan.
13. AROMATIC BIOSYNTHESIS SHIKIMIC ACID PATHWAYS
The majority of the aromatic compounds are
biosynthesized via Shikimic acid pathways. The
Shikimic acid pathway plays significantly important in
the genesis of the aromatic building blocks of lignins,
and also leads to the formation of phenyl propane
units like flavones and isoflavonone, coumarins,
tannins, vanillin and terpenoid quinones.
The Shikimic acid pathway appears to be an
important route from carbohydrate for the
biosynthesis of Co- C1 units (phenylpropane
derivatives).
For higher plants, the presence of enzyme system
responsible for the synthesis of Shikimic acid has
been confirmed.
14. The important steps involved in the genesis of Shikimic
acid pathway as follows:
Shikimic acid pathway starts with the Erythrose 4
phosphate (obtained from the pentose phosphate
pathway) and phosphoenol pyruvate (obtained from
Glycolysis pathway) on aldol condensation to yield
DHAP (2-keto-3-Deoxy-D-arabinoheptonicacid-7-
phosphate).
DHAP on removal of phosphoric acid cyclizes to form 3-
dehydroquinic acid, which on dehydration to form 3-
dehydroshikimic acid which yields Shikimic acid by
reduction.
Shikimic acid through phosphorylation and elimination
reactions forms a very important intermediate
compound, Chorismic acid.
15. Chorismic acid is an important branching
point; anthranilate synthase uses chorismic
acid as substrate to give anthranilic acid
which is a precursor for Tryptophan.
Chorismic acid via simple rearrangement
gives prephenic acid.
Prephenic acid on dehydration and
decarboxylation yields precursor of
Phenylalanine i.e. phenylpyruvic acid.
On dehydrogenation and decarboxylation,
prephenic acid yields p-hydroxyphenyl pyruvic
acid which is a direct precursor of Tyrosine.
The schematic representation of Biosynthesis
of aromatic compounds via Shikimic acid
pathway as follows:
16.
17. INTRODUCTION: Isoprenoid pathway is also known as
terpenoid pathway or acetate mevalonate pathway.
This pathway contributes about one third of all known
secondary metabolites.
The isoprene units from this pathway is contributed in
biosynthesis of many other metabolites such as
anthraquinones, napthaquinones, terpenoids and indole
alkaloids.
The important steps involved in the biogenesis of
Mevalonate pathway as follows: Acetate mevalonate
pathway begins with molecule of acetyl CoA which is
produced from pyruvic acid, end product of glycolysis.
First two molecules of acetyl CoA forms acetoacetyl CoA
through Claisen condensation.
18.
19. Amino acid are the compound which comprises
of amino group as well as carboxylic acid group
because protein Are linear polymer of amino
acids.
Amino acids are amphoteric act as a acid or
base ionic electrolyte ion for light amphoteric
electrolyte that is a pH gradient under electric
field moves to its isoelectric point amino acids
can connect with the peptide Bond involving
amino and carboxylic group peptide bonds are
planar and partially ionic.
20.
21. Secondary plant metabolites- The secondary
metabolites are biosynthesized from primary
plant metabolites . Secondary plant
metabolites are basically potent in their
action and they are associated with marked
pharmacological actions on human body.
22. Living plant may be considered as a
biosynthetic laboratory not only for the primary
metabolites like sugars, amino acids and fatty
acids but also for a nucleotide secondary
products of pharmaceutical significance such as
glycosides, alkaloids, flavonoids, volatile oils
etc. The various biosynthetic reaction occurring
in plant cells are enzyme dependent which are
reversible.
23. It is through the control of enzymatic activity that plant metabolism
is directed into specific biosynthetic pathways.
Biosynthesis: Formation of Chemical compounds by a living
organism.
Biogenesis: Production or generation of living organisms from other
living organism.
Primary Metabolite: Primary metabolites are required for general
growth and physiological activity of plants because of their basic
metabolism.
Eg: Amino acid, fatty acid, Nucleic acid, Carbohydrate and protein
Secondary Metabolite: Secondary metabolites are derived
biosynthetically are from the primary metabolites but usually
restricted to specific taxonomically group. They may represent
chemical adaptations to environmental stresses or they may serve
as defensive or protective against microorganism, insect and higher
herbivorous predators. They are present in much smaller quantities.
Eg: Alkaloids, Glycoside, Volatile oil, Flavonoid, lignin, Carotenoid
etc.
24. Oxidation
Reduction
Condensation
Amination
Methylation
Cyclization etc.
Basic metabolic pathways are:
The production of secondary metabolites is mostly
dependent on genetic make -up which are
selectively excel in the fundamental process
involved in their biosynthesis. These genetically
controlled processes can be termed as basic
metabolic pathways.
25. The understanding of biosynthetic pathways depends on various
specialized techniques. They are five major techniques which are
generally used for the synthetic study of primary and secondary
metabolites. They are as follows.
Tracer technique
Use of isolating organs or tissues
Grafting method
Use of mutant strains
Enzymatic studies
Tracer techniques: In tracer technique, radioisotopes are frequently used
as tracers or tagged in various fields. Radioisotope is added to the
reactant and its movement is studied by measuring radioactively in draft
plants.
Principle: Tracer technique which utilizes a labeled compound to trace or
find out the different intermediates and various steps involved in
biosynthetic process in plant at given rate and given time. When these
labeled compounds are administered in to the plants, they become a part
26. Introduction; The elements existed with identical chemical properties but different
atomic weights are, termed as isotopes. Isotopes may be stable.
Eg: 2H, 13C, ISN, 180. Nucleus may be unstable
Eg: 1H, 14C and decay with emission of radiation. It is possible to detect these
isotopes by suitable methods. These isotopes can be incorporated in to a
presumed precursor of plant constituent and used as markers in biogenetic
experiment.
Significance of tracer techniques: Tracing of biosynthetic pathway by
incorporating radioactive isotopes in to the precursor or starting material. Eg. By
incorporation of HC to phenylalanine, the biosynthesis of cyanogenetic
glycosides, prunacin can be traced. Location and quantity of the compound can
be determined in biological system.
Different trace elements are used for different studies:
1. For studies on protein, alkaloid and amino acid. Nitrogen atom gives more
specific information than carbon atom.
2. For studies on glycosidic linkage: O, N, S and C atom.
3. For studies on Terpenoids : O atom
Basic steps involved in Tracer techniques:
a. Preparation labeled compound.
b. Incorporation of labeled compound to tissue system.
c. Separation or isolation of labeled compound from tissue system.
27. a) Precursor-product sequence
b) Competitive feeding
c) Sequential analysis
d) Use of stable isotopes
28. Precursor-product sequences:
In this method, the constituent is labeled it is fed
to the plant for specific period of time, The
constituents produced in plant are isolated and
purified and its radioactivity is determined Further
proof is needed because the labeled precursor
fed may not be the direct precursor.
In fact, the compounds may enter the general
metabolite pathway of plant and become
distributed randomly through a whole range of
products. Further evidence can be made by
double and triple labeling experiments by using
different isotopes or by one isotope at two or
more position in the moles. Ex: In Nicotiana
glayca two double labeled lysine's to determine
which hydrogen of the lysine molecule was
involved in the formation of the piperidine ring of
anabasine.
29. Competitive feeding: In this method, the value
in determining which of two possible
intermediates is normally used by the plant.
Competitive feeding could distinguish
whether B or B' was the normal intermediate
in the formation of C from A.
Inactive B and B' are fed with labeled A to
separate groups of plants and a control is
performed by feeding labeled A only to
another group. If the incorporation of activity
into C is inhibited in the plants receiving B but
is unaffected in the group receiving B’. May
conclude that the pathway from A to C
proceeds via in B.
30. Sequential analysis: A second method of investigation
with 14C is to grow plants in an atmosphere of 14CO2
and by analysis of the plants at given time interval to
obtain the sequence in which various related
compound become labeled. Degradation of the isolated
radioactive compounds is important because some
units of the molecule may become labeled more rapidly
than other. It is successfully used in the elucidation of
the path of carbon in photosynthesis and also for
determining the sequential formation of the opium,
hemlock, tobacco alkaloids. Exposure period of the
plant is short as 5mins. Eg: biosynthesis sequence in
Mentha piperata.
31. Isolated organs and tissues: The cultivation of
isolated organs and tissue of plant elimination
interference from other parts of the plant which
may produce secondary changes in the
metabolites. Used for feeding experiment in
conjunction with labeled compound. Also it is
useful for the determination of the site of
synthesis of particular compounds.
32. Grafts: Grafting techniques have been used in
biosynthetic studies for the determination of
the sites of primary and secondary metabolism
of secondary plant products. Alkaloid formation
by grafted plants has been extensively studied
in Nicotiana and tropane alkaloids are
producing solanaceae. Eg: Tomato scions
grafted on to Datura stocks are accumulation
of tropane alkaloid. Datura scions on tomato
stocks contain only a small amount of tropane
alkaloids. The main site of alkaloid synthesis is
to be the datura species.