New Strategies for Evaluating Natural Products
| Home | | Pharmacognosy |Chapter: Pharmacognosy and Phytochemistry : Biological Screening of Herbal Drugs
The fundamental problem for chemists working on natural products used to be that of choosing which pharmacological principles and methods to use to understand the possible biological use of any given substance.
NEW STRATEGIES FOR EVALUATING NATURAL PRODUCTS
The fundamental problem for chemists working on natural
products used to be that of choosing which pharmacological principles and
methods to use to understand the possible biological use of any given
substance.
The RICB (Reseau d’interaction chimie—Bioiogique or Chemical
Biological Interaction Network) has come up with lots of objectives for helping
the chemists as described below.
The RICB helps chemists by providing assistance from
biologists, who use their knowledge and sophisticated methods of observation
for the pharmacological activity of any given substance. Rather than the
current classical procedure of observing an overall pharmacological effect
(e.g. measurement of femoral artery blood flow in dogs), it is now possible to
observe the effect of the substance on any one of the underlying components of
the overall peripheral pharmacological effect (e.g. binding to α- or β-adrenergic receptors, or to
angiotensin or vasopressin receptors, or the effect of posterior pituitary
vasopressin). The RICB aids biologists by providing new tools for examining
receptors, neuromediators, ion channels, and membrane-coupling mechanisms. It
can thus be said that, thanks to deriva-tives of yohimbine (indole alkaloids
from the Rubiaceae and Apocynaceae), the alpha-1 and alpha-2 subtypes of
adrenergic receptors were distinguished. Likewise, for-skolin, a labdane
diterpene, enabled progress to be made in understanding the adenylate cyclase
system. Morphine, ouabain and tetrodotoxin are other examples of biological
agents derived from the chemistry of natural materials. Biologists can also
make use of the chemists’ extra skills in resolving certain problems at the
frontiers of biology, such as extraction, labelling, and molecular modelling.
In general, the RICB has also provided a discussion forum
for a collaboration between two disciplines that are relatively unfamiliar with
each other and for developing new strategies in the evaluation of natural or
synthetic substances. By using different animal models, the
phyto-pharmacological potentials of different plant species, including Nelumbo nucifera and Leucas lavendulaefolia have been
reported.
Related Topics
