[ps2id id=’background’ target=”/]
BACKGROUND
Extractive values are used for evaluation of crude drugs when they cannot be estimated by any other method. Extractive values by different solvents are used to assess quality, purity and to detect adulteration due to exhausted and incorrectly processed drugs.1
Crude drugs contain a number of constituents and these have a selective solubility in different solvents. Water, alcohol, alcohol/water mixtures, generally 45%, 60%, 90% ethanol, ether are used as solvents to prepare ethanol soluble extractive, water soluble extractive (chloroform water), ether soluble extractive, etc.
Extractive values indicate the presence of different constituents and TLC fingerprints can be developed for identification and semi-quantitative analysis from these extracts.
Ginger contains some water soluble constituents. If the ginger is exhausted with water or soaked in water for a long time while cleaning, the water soluble extractive will have a lower value than the official limit. However, Ginger exhausted with chloroform water passes this test.
[ps2id id=’requirements’ target=”/]
REQUIREMENTS
Water soluble extractive not less than 10%
250 ml conical flask with stopper
Chloroform Water
Shallow flat-bottomed dish
Water bath
[ps2id id=’procedure’ target=”/]
PROCEDURE
Weigh accurately about 5 g of coarsely powdered drug into a 250 ml conical flask with stopper. Add 100 ml of chloroform water. Shake the flask frequently during first 6 hr. Keep it aside without disturbing for 18 hr. and then filter. Pipette out 25 ml of the filtrate and evaporate to dryness in a weighed shallow flat-bottomed dish on a water bath. Then dry the residue at 1050 C to a constant weight. Calculate the percentage of water-soluble extractive.
% of water soluble extractive = weight of residue/weight of the drug x 100
It is expressed as percent w/w of the air-dried drug.
[ps2id id=’conclusion’ target=”/]
CONCLUSION
Water-soluble extractive value of Ginger is ____.
[ps2id id=’references’ target=”/][ps2id id=’1′ target=”/]
REFERENCES
- Joshi S, Aeri V. Practical Pharmacognosy, 1st edition, Frank Bros. & Co. New Delhi; 2009: 255.
