Phytochemical, antimicrobial, insecticidal and brine shrimp lethality bioassay of the crude methanolic extract of Ajuga parviflora Benth

Abstract

Methanolic extract of medicinal herb Ajuga parviflora Benth. was evaluated for phytochemical screening (the plant extract showed the presence of aromatic compounds, carbohydrates, glycosides, tannins, alkaloids, polyphenols, quinines and dions, aminophenols, steroids/sterols, flavonoids and terpenoids), antimicrobial activities against various strains of bacteria and fungi by using disc diffusion method and insecticidal activities against red flour beetle (Tribolium castaneum), wheat weevil (Sitophilis granaries) and their larvae. The crude extract showed anti-bacterial activity against all strains with a maximum zone of inhibition of 12mm diameter against Citrobacter and Pseudomonas aurogenosa. Standard drugs Ampicillin, Gentamicin and Amoxicillin were used in parallel. The crude extract did not show antifungal activity against the tested strains of fungi even at high doses. The crude methanolic extract was also used for insecticidal activity against the two types of insects and their larva. The extract showed no significant mortality in the tested strains. For brine shrimp lethality bioassay different concentrations 10, 100 and 1000ug/ml of the medicinal herb A. parviflora methanolic extract were used. After 24 hrs the percent mortality and LD50 value was calculated through probit analysis. The LD50 value of extract was 321.42µg/ml while that of standard drug cyclophosphamide was 16.09ug/ml.