Phytotoxic and antimicrobial activities of saponin extracts from lemon grass

Abstract

Phytotoxic activity of the Lemon grass saponins was tested on the germination of maize and bean seeds and on the growth of the germinated seedlings.   The saponin extract inhibited the germination of maize and bean seeds and the growth of the shoot and root of the seedlings.  The bean seeds were more sensitive to the saponin effect than the maize seeds because their growth was more inhibited.  The inhibition was concentration-dependent in that the higher the saponin concentration the higher the inhibition of shoot or root-length.

     Saponin extract from Lemon grass (Cymbopogon citratus) was tested on six pathogenic microbes namely Staphylococcus aureus Bacillus substilis, Escherichia coli, Pseudomonas aeruginosa, Candida albican and Aspergillusniger.  The saponin extract inhibited the growth of all the microbes and was comparable to the effects produced by Ampicillin, a standard antibiotic.  At 10% dose concentration, the saponin extract was 81% as effective as Ampicillin (30 mg/ml) inhibiting the growth of Escherichia coil

     Gram- negative bacteria are more sensitive to the saponin extract because their growth was more inhibited.  This report justifies the application of Lemon grass in traditional healthcare delivery in the West African sub region.