New enolic type bioactive constituents from Hyptis suaveolens (L.) Poit

The objective of the present study is to isolate the lead phytochemical from the Hyptis suaveolens (L.) Poit. based on bioassay guided isolation from the promising crude extract. The crude extracts were prepared by using Hexane, petroleum ether, ethyl acetate, chloroform, methanol, acetone and water as solvents by cold percolation mechanical agitation method and hot extraction method, the dried crude extracts further subjected to bioactivity studies. Among the crude extracts, ethyl acetate extract is showed promising antifeedant, oviposition deterrent, ovicidal and insecticidal activity against Helicoverpa armigera, Spodoptera litura (Fab.) (Lepidoptera: Noctuidae), it was further taken for flash column chromatography purification which yields twenty fractions. From the bioactivity studies, fraction II and IV contains active constituents which inhibit the feeding ratio of the H.armigera and S. litura and it is apparent from the table. As per the data, fraction II and IV showed statistically significant ovicidal activity and further purified by preparative liquid chromatography yields two bio active molecules with 99% purity (2E)-1- (2-hydroxy phenyl) pent-2-en-1-one (I) and 1-[(3-hydroxy-5, 5-dimethyl cyclohex-3-en-1yl) oxy] hexan-3-one (II). Presence of these two phyto chemicals is being reported for the first time from this plant, Natural products and their derivatives have historically been invaluable as a source of therapeutic agents. But, at present role of natural products in the pharmaceutical industry has declined, due to lack of compatibility of traditional natural-product extract libraries with high-throughput screening. Attempts were made to enrich the bioactivity of phytochemical (I) & (II) through semi synthetic modification by employing boron reagents, which results crude mixture and it shows excellent bioactivity against H.armigera, S.litura.

Author(s): S. Venkatesan Jayakumar* and S. M. Krishna Ganesh

Abstract | PDF

Share This Article