Antioxidant,antibacterial and cytotoxic effects of the phytochemicals of whole Leucas aspera extract

Objective:To investigate the antioxidant,antibacterial and cytotoxic activity of whole Leucas aspera（Labiatae）(L.aspera)alcoholic extract.Methods:Whole L.aspera powder was extracted by absolute ethanol（99.50%）.The ethanolic extract was subjected to antioxidant,antibacterial and brine shrimp lethality assay.Results:The extract showed potent radical scavenging effect（antioxidant）with IC;value of（99.58±1.22）μg/mL which was significant（P<0.01）in comparison to ascorbic acid with IC;value of（1.25±0.95）μg/mL.In case of antibacterial screening,the extract showed notable antibacterial effect against the tested microbial strains.Significant（P<0.05）zone of inhibitions against Gram positive Bacillus subtilis[（12.00±1.32）mm]and Bacillus megaterium[（13.00±1.50）mm],Staphylococcus aureus[（8.00±0.50）mm]and Gram negative Salmonella typhi[（6.00±0.50）mm],Salmonella paratyphi[（8.00±1.00）mm],Shigella dysenteriae[（9.00±1.32）mm]and Vibrio cholerae[（9.00±0.66）mm]was observed.In brine shrimp lethality bioassay,the extract showed the LC;value as（181.68±2.15）μg/mL which was statistically significant（P<0.01）compared to positive control vincristine sulfate[LC;=（0.76±0.04）μg/mL].Conclusions:The results demonstrate that the ethanolic extract of L.aspera could be used as antibacterial,pesticidal and various pharmacologic actives.