Page 134 - Pharmacognosy 2 PG303

Pharmacognosy-2 (PG303) Level 2 Clinical Pharmacy-Pharm D

Extract 0.1 g of cannabis powder with 10 ml Petroleum ether extract. Add few drops of alcoholic

KOH to 1 mL of the extract, shale well then add amyl alcohol, mix well, violet-pink color is

produced.

.

3- Negam test

Evaporated petroleum ether extract of cannabis + acetaldehyde + vanillin HCl reagent green

color changes to blue then violet.

4- Ghamrawy test
Evaporated petroleum ether extract cannabis + alcoholic solution of p-dimethyl
aminobenzaldehyde (few drops) + H2SO4 (few drops) → rose pink color change into red by heating
→ change to blue on addition of water.

ERGOT

The dried sclerotium of the fungus, Claviceps purpurea (family: Hypocreaceae),
developed in the ovary of rye plant, Secale cereale (family: Gramineae). It is imported chiefly
from Spain, Poland, Russia, and Austria.

Life cycle

1- In the early summer when the rye plants are in flower, spores carried by the wind lodge at
the base of the ovary of the rye flower and germinate.

2- The hyphae penetrate the ovary, which is replaced by the fungus, become enlarged and
spongy at the upper end where the hyphae are protruding and bearing numerous spores.
This stage is known as (Sphacellia stage).

3- The fungus secretes a saccharine fluid known as (honey dew). Insects are attracted by the
secretions and carry out the spores to other rye plants.

4- At the end of the season, as the rye ripens, a dense core of compact hyphae develops in the
diseased ovary and grows out to project from the ear of the rye plant bearing at its apex the

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