Biological Methods for Estimation of Botanicals: An Overview

Botanical products are “heterogeneous” due to the presence of mixture of bioactive plant components. Physical analytical are usually insensitive to the chemical complexities found in crude botanical extracts. Also physical or chemical analysis of a single component in such mixtures is not completely satisfactory. The goal of many phytochemists has been simply to isolate, characterize, and publish a plethora of novel botanically-derived chemical substances without regard to bioactivities. To achieve applied meaning and significance, today's work in natural product chemistry must incorporate bioassays. Extracts must be screened for biological activity, the “active” extracts selected, fractionations directed with bioassays, and the bioactive compounds identified and then exploited. We have made an attempt to summarize different bioassays (Brine Shrimp Lethality, Crown Gall Tumors on Potato Discs, Yellow Fever Mosquito Test, The Lemna Bioassay) which are useful in the detection of biologically active components of botanical extracts.