Page 81 - phytochemistry general program

Estimation of ergot alkaloids

The total ergot alkaloids can be determined in the powdered drugs or
pharmaceutical preparations by one of the following techniques:

1. Colorimetrically, based on that the blue color produced with using Van Urk's
reagent is concentration dependent. The absorbance is measured at 590 nm and

compared with a with a standard reference alkaloid.

2. Fluoremetrically, based on that the alkaloids are fluorescent.

Production of ergot alkaloids

:Production in artificial culture media

Tissue culture technique has been adopted for the commercial production of
Some attempts produced only the clavine- type alkaloids that are .ergot alkaloids

.of less medicinal value

Claviceps species elaborated good yield of Other experiments with certain
mixture of lysergic acid derivatives. Results of these latter experiments are of
great commercial significance; as the total lysergic acid amides and /or derivatives
can be easily hydrolyzed to give free lysergic acid that can be converted to

ergonovine by reaction with 2- aminopropanol.

Nux vomica alkaloids

Strychnos species (Family Loganiaceae) Strychnos nux- vomica and Some
Strychnos ignatii contain a number of dihydroindole alkaloids the most important of

which are strychnine and its dimethoxy- derivative brucine.

Nux vomica the alkaloids are located chiefly in the seeds, but are also In
present in the leaves, wood, bark and other organs of the plant in variable

amounts. Some of the alkaloidal content is in the form of N-oxides.

In the seeds strychnine is usually located in the inner parts of the
endosperm, while brucine occurs largely in the outer layers of the endosperm.

Nux vomica varies from 0.2 to 5%; and for The total alkaloidal contents of
pharmaceutical purposes the seed is required to contain not less than 1.2 % of
strychnine; so, the seed is assayed for its strychnine content and not for total
alkaloids.

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