Transcript
1 Spring Semester 2013
Botany and Medicinal Plants
Department of Pharmacognosy Prof. Nahla Ayoub Lecture (4)
cell cONTeNT NaTural MeTabOliTes
2
Types of Natural Metabolites: A) Primary metabolites: Carbohydrates.
Amino acids (Protein).
Fats.
Function: Participate in cellular activities & used as precursor for the biosynthesis of 2° metabolites.
Distribution: Distributed universally throughout the plant kingdom.
B)Secondary metabolites:
Represent the majority of natural products e.g., alkaloids, glycosides, tannins, volatile oils, steroids ... etc.
Have a restricted distribution (perhaps only found in certain species, genus & family ... etc.).
Function: Are not clear, may or may not be essential.
The cell cONTeNTs
I-Primary Plant Metabolites
II- Products of Metabolism
A-Carbohydrates (Starch)
B- Proteins
C- Fixed oil & fats
i-Crystals
II- Gums, Mucilages & pectins
III- Resins & Resin Combination IV- Tannins
V- Volatile oils VI- Alkaloids
VII- Glycosides VIII- Antibiotics
IX- Aflatoxins X- Vitamins
XI-Hormones XII- Enzymes
FOOd sTOrage prOducTs priMary plaNT MeTabOliTes
A- Starch As granules in all storage organs e.g. roots rhizomes and seeds. The major sources of starch intake worldwide are the cereals (rice, wheat, and maize) and the root vegetables (potatoes) Starch is a polysaccharides of high molecular weight ( polymer of Alphaα-glucose and formed during photosynthesis) . Detection It gives blue color with iodine.
Potato Starch
5 2/26/2013
uses OF sTarch
Adjuncts in tablet formulation: diluents, binder,
desintegrants, anti-caking agents
Food technology, paper production, textile industry,
glues, adhesives .
Dusting powder for cosmetic preparation.
As lubricant and in treatment of iodine poisoning.
As indicator for the iodine titration.
Drugs derived from starch.
Potato starch grains (viewed under high power)
Maize starch grains (viewed under high power)
Rice Starch grains
7
B- Proteins As aleurone grains (storage and source of proteins ) in seeds.
It is composed of a large number of amino acids united by peptide linkage. They are complex nitrogenous organic substances of high molecular weight. It composed from Matrix, globoids and crystalloid
Detection It gives red color with Millon’s reagent.
8
Aleurone grains: composed from Matrix, globoids and crystalloid
9
The aleurone layer of the seed lies between the outer pericarp and the inner starchy endosperm.
Aleurone grains
Pericarp
Aleurone Endosperm (Starchy)
Oil drops
10
C- Fixed oil and fats Found in seeds Reserve fats occur as crystalline masses or oil drops (endosperm ) Detection Sudan III red color They are used pharmaceutically in • Soaps, liniment and plaster. • Stimulant cathartic (castor seed oil).
• Solvent for IM. Injection (in steroidal drugs).
e.g. peanut, cotton seed, sesame and corn oils.
• In treatment of hypercholesteremia e.g. olive oil.
by-prOducTs OF MeTabOlisM I-Crystals
A- CALCIUM OXALATE
1- Prisms 2- Rosette and cluster Cluster: Numerous prisms or pyramids or both grown together to form spherical masses with projecting point
Rosette : Crystals having a
large center from which crystal radiate,
appear to have a toothed circumference.
e.g. in aleurone grains of Umbelleferae.
Crystals may be reserve or waste products of cellular activity. Calcium salt in the soil + oxalic acid (metabolism of carbohydrate)
e. Rhubab rhizome
e.g. Hyoscyamus
( long prism) e.g.in Quillaia bark
3- Needles (acicular) 4--Microcrystal or sandy crystal
commonly occur in bundles (raphides) e.g. Squill
Very small, e.g. in belladonna leaf (microsphenoidal) and cinchona bark (microprismatic).
13
Forms of CALCIUM OXALATE
1- Prisms
3-Rosette
2-Cluster
5-Microcrystal or sandy crystal
4-Needles (acicular)
Rosette
14 14
Special arrangement of Ca Ox
Crystal sheath [Senna, Cascara] Crystal layer
(Stramonium)
e.g. Quillaia e.g. Rhubarb
e.g. Squill e.g. Hyoscyamus
calciuM OxalaTe crysTals
Rosette
e.g. Senna in aleurone grains of Umbelleferae.
Raphides
e.g. Stramonium e.g. Belladonna
e.g. Squill
Rosette
in aleurone grains of Umbelleferae.
17
Atropa belladonna vein islet Idioblasts
Datura stramonium vein islet Crystal layer
b- calciuM carbONaTe:
Cystolith hair of Cannabis sativa
Identified by effervescence with dil. HCl.
c- silica: Skeleton of diatoms
(kieselguhr).
Sclerenchymatous layer of cardamom seed.
Calcium carbonate deposit
19
aNTibiOTics Compounds synthesized
by certain molds and fungi
Having bacteriostatic activity.
e.g. Penicillin and tetracycline.
aFlaTOxiNs Mycotoxins developed by mouldy grains
Cause serious reaction
They are potent carcinogen, and mutagen.
e.g. Aflatoxin B1, G1 developed by Aspergillus.
ViTaMiNs - Organic compound necessary to the normal
growth and maintenance of life in animals including human.
- Isolated from plant or animal purified and concentrated for use as drugs e.g. (Ascorbic acid)
21
hOrMONes Active hormones
secreted by the endocrine glands.
They control the growth, development and metabolism in various ways. e.g . Auxins, Cytokinins.
eNzyMes Organic bio-catalysts
produced by living cells.
They make most of the chemical reactions which make up life processes e.g. Amylase, Protease, Lipase
top related