Antibacterial and anti-oxidant potential of Yucca elephantipes and comparative safety profile of its various extracts

Abstract

In the present study, different extracts of yucca elephantipes including aqueous, ethanolic and methanolic were evaluated for their antibacterial as well as antioxidant activities, while the toxicity studies were also carried out along them. Disc diffusion method was used to evaluate anti-bacterial activity of the extracts against certain bacteria including gram positive S. aureus and B. subtillus as well as gram negative P. aeruginosa and E. Coli. Results showed that plant extracts have excellent antibacterial activity against E. coli as compared to S. aureus. As far as E. coli is concerned, the activity of these extracts was found out to be more than the standard drug. Hence, we can conclude that the extracts of yucca elephantipes showed more activity against gram negative bacteria rather than gram positive. The In vitro antioxidant activity of aqueous, ethanol and methanol extracts was tested by DPPH scavenging activity, reducing power assay, total phenolic contents, and total flavonoid content. Highest amount of TPC was found in methanolic extracts (48.56 mg of gallic acid e/gE) while that of TFC was found in n- hexane (33.31 mg of catechin/gE). As far as reducing power assay is concerned, n-hexane exhibited the highest activity (33.07%) among all. Ethanolic extract of yucca elephantipes showed highest DPPH scavenging activity. Significant difference was observed between the anti -oxidant activity of ethanol, methanol and n-hexane. Different doses of extract 250mg/kg and 500mg/kg were orally administered to rats to evaluate the sub-acute toxicity. At the end of study, tissue samples and blood was collected for biochemical and hematological parameters. Hematological parameters showed that the high dose of methanolic extract decreased the level of RBCs, WBCs, PLT and HGB. These results suggested the use of yucca elephantipes as a valuable source of natural antibacterial and antioxidants.