Guns And Muciges Flashcards
plant hydrocolloids with similar constitutions of high molecular weight made of sugar and uronic acid units (polyuronides).
Gums and mucilages
What do uronjc acids form salts with and what are the salts classified as
Ca, Mg and K
Classified as
➢Anionic
➢Non-ionic salts of polysaccharides
What are the families gums are common in
- Leguminosae
- Rosaceae
- Sterculiaceae
- Rutaceae
Functions of gums
- Storage material
- Water storage reservoir
- Protection for germinating seeds.
Differences btn gums and mucilages
Gums are formed by breakdown of cells but Mucilages are normal products of metabolism formed within the cell (intracellular formation).
Gums pathological products which form during
injury and unfavourable conditions (drought)
Mucilages are physiological products secreted in the cell and laid down there like hemicellulose
Gums readily dissolve in water to form sticky, colloidal dispersions but Mucilage swells and form slimy masses in water.
Sources of gums
shrub or tree exudates- acacia, karaya, tragacanth.
•marine gums- agar, algin
•seed gums- guar, locust bean
•microbial gum- dextran, xanthan
Herbs containing mucilages
- Psyllium
- Cocoa etc
What are the therapeutic use of gums
emollient
•which means that they coat and protect the skin
•Demulcent-which means that they coat and protect the lining of the gastric tract
- Reduces irritation of the bowel, gut
- alleviates cough,
- alleviates ulcers, lesion, inflammation in the gut and reduces excessive acid secretion
- as dental adhesive
- As bulk laxatives
- Absorbs large volumes of water
- Indigestible and hence act as dietary fiber.
Do gums have nutritional value
Little or no value
•The dried gummy exudate from Astragalus gummifer and other species of Astragalus (Leguminosae)
Tragacanth
What are the two fractions of tragacanth
Bassorin- methoxyl groups present insoluble, swells in water
•tragacanthin –no methoxyl group.
soluble in water.
Are bassorin and tragacanthin soluble in alcohol?
No
How can bassorin and tragacanthin be separated
Bassorin and tragacanthin may be separated by ordinary filtration of a dilute mucilage.
What happens to tragacanth upon hydrolysis
Acidic portion-yields galacturonic acid, galactose and xylose
•A neutral polysaccharide-gives arabinose and lactose
•Also contains water, traces of starch, cellulose and nitrogenous substances
Physical characteristics of tragacanth
The gum is white or pale yellowish-white in colour
●Translucent
●Breaks with a short fracture
●Odourless and have little taste
●Swells into a gelatinous mass in water (small section dissolves)
Chemical properties of tragacanth
Addition of dilute iodine
-few blue points visible
Stronger iodine
-greenish colour
●Forms precipitate with dilute lead acetate
●Boiled with KOH-gives a canary yellow colour
●Peroxidase/oxidase test-no blue colour with benzidine in alcohol
What are the uses of tragacanth
Pharmaceutical-suspending agent, emulsifier, and as adhesive.
•as demulcent and emollient in cosmetics.
How are acacia tapped
Tapped by making incisions at the bark and peeling of both above and below the cut
What are the constituents of acasia
arabin
●Contains 12-15% water and several enzymes like oxidases and pectinoses
a polysaccharide which on hydrolysis yields arabinose, galactose, glucuronic acid and rhamnose.
Arabic acid
Physical properties of acacia
Gum is white or very pale yellow in colour
•Breaks with a glassy fracture
•It is odourless with a bland or mucilaginous taste
•Completely soluble in an equal weight of water
•Solution slightly acidic
Chemical properties of acacia
10% solution of dilute lead acetate-no precipitate
- No colour reaction with iodine
- Gives positive peroxidase test
- Gives no reaction for tannins with ferric chloride
Uses of acacia
Emulsifier and suspending agent,
•binder in tablet granules,
•demulcent, emollient and adhesives.
•Used in lozenges, etc. its demulcent properties are employed in various cough, and throat preparations
•Used in food, drinks and other industries.
Dried gummy exudates from Sterculia urens, S. villosa, S. tragacantha or other species of Sterculia. (Sterculiaceae).
Karaya gum
Uses of karaya gum
The granular grades are used as a bulk laxative
The powdered gum is used in lozenges, pastes and denture fixative powders, useful as an adhesive.
As stimulant.
Dried gummy exudates
•contains D-galactose units.
•Sometimes as a substitute for gum Arabic
Albizia
Cleaned dried ripe seed of
•Plantago psyllium,
•P. ovata or
•P. indica (Plantaginaceae).
Plantago seeed
What is the most important part in plantago seed and where is the mucilage
The husk of seed
Mucilage is in outer wall
Use of plantago seed
treatment of chronic constipation
•as demulcent.
How is quality of plantago seed
quality -swelling index/ factor (1g in 25 ml to 20 ml)
•This is defined in the BP as the volume in millilitres (mL) occupied by 1 g of a drug, including any adhering mucilage, after it has swollen in an aqueous liquid for 4 h/24h.
