4. Cannabis
Synonyms Indian Hemp;
Indian cannabis; Marihuana; Marijuana; Pot; Grass; Weed; Bhang; Ganja; Charas,
Hashish.
Biological Source Cannabis consists
of the dried flowering tops of pistillate plants of Cannabis sativa L.,
(C. satira var. indica Auth.), belonging to family: Moraceae.
Preparation After years
of intensive and extensive research carried out on the selective cultivation of
Cannabis, two of its genetic types have been evolved, namely: (i)
Drug Type, and (ii) Hemp Type.
These two distinctly
separate genetic types of Cannabis shall be described briefly as stated
below:
A. Drug type (Cannabis): It
is, in fact, the rich (upto 15%) in the psychoactive constituent (–)-∆9-trans-tetra-hydrocannabinol
(∆9-THC) as shown below:
The ∆9-THC is usually
concentrated into a resin that is secreted right into the trichomes located
on the small leaves (bracts) and bracteoles (i.e., the leaf-like
structure which encloses the ovary) of the flowering tops of the female
plant. Interestingly, for the specific drug usages either the resin (hashish)
is employed or the flowering tops of the female plant (marijiana).
Nevertheless, the male plant also generates an equivalent quantity of the
active constituents; however, it is not concentrated into a resin but found
throughout the entire plant.
B. Hemp Type (Cannapis): It
contains surprisingly very little active principal. Cannabidiol is the predominant
cannabinoid present in it as given below:
The hemp-type cannabis also
possesses the elongated bast* fibers which is very much desired in the
manufacture of ropes.
Chemical Constituents The
chemical constituents ∆9 THC and cannabidiol present in the drugtype and
hemp-type cannabis have already been discussed above. Besides, the resin
contains several active constituents, such as: cannabinol, cannin, cannabol,
tetrahydrocannabinol, cannabigerol, cannabichromene and ∆8-tetrahydrocannabinol.
It also contains choline,
volatile oil and trigonelline. However, the Indian Hemp seeds contain 20%
of fixed oil.
Chemical Tests
1. Shake 0.1g of resin with 5
ml petroleum ether (60-80°C) and filter. To 1 ml of the filtrate, add
2 ml of 15% solution of HCl gas
in ethanol, when a red colouration appears at the junction of the two layers.
However, after shaking, the upper layer becomes colourless while the lower one attains
a distinct orange pink colour, which finally vanishes upon addition of water.
2. Extract 1g of resin with
methanol, filter and evaporate to complete dryness. Again extract the resulting
residue with petroleum ether (60-80°C), filter directly into a separating
funnel and extract the ethereal layer successively with 5% (w/v) Na2CO3
and 5% (w/w) H2SO4. Wash the ethereal layer with
distilled water, decolourise with powdered activated carbon, if necessary, and
evaporate the filtrate. Add to the residue a few drops of N/10 alcoholic KOH
solution, when a purple colouration is obtained.
Uses It has been used as
a sedative in equine colic.
-------------------------------------------------------
* Bast: Fibrous
material obtained from the pholeum of jute, flax etc., used for making rope,
matting etc.,
Source:Pharmacognosy And Pharmacobiotechnology By Ashutosh Kar
Source:Pharmacognosy And Pharmacobiotechnology By Ashutosh Kar
0 Comment:
Post a Comment