Phytochemical and biological studies of extracts of flower heads of spitanthes mauritiana D.C.

Abstract

Phytochemical analysis of extracts of the flowers of spilanthse mauritiana DC revealed the occurrence of alkaloids, anthocyanins, steroids, polyoses, tannins, flavonoids, coumarins, polyacetylenes and reducing compounds.

Chromatographic purification led to five homogenous samples. Uv and ir spectral analysis suggested the presence of triple and double bonds as well as hydroxy or amine or amide groups.

One of the fractions yielded a crystal after repeated chromatographic purification. The Uv, ir,ms and nmr data of the chrystals led to the identification of the compound as stigmasterol. The methanol and chloroform extracts of the flowers gave LD50 of mosquitolarvicidal activities at 31.6 ppm and 2.23 ppm respectively.

The methanol extract showed no molluscidal activity upto 500 ppm. Fractions three upto ten from chloroform extract purified on open silica gel column showed percentage mortality rate of 40,68,90,98,94,78 and 60 respectively at the concentration of 5 ppm against mosquito larvae.