title: Antioxidant, antibacterial and cytotoxic effects of the phytochemicals of whole Leucas aspera extract.
abstract: 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 IC50 value of (99.58±1.22) µg/mL which was significant (P<0.01) in comparison to ascorbic acid with IC50 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 LC50 value as (181.68±2.15) µg/mL which was statistically significant (P<0.01) compared to positive control vincristine sulfate [LC50=(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.
authors.affiliation: Department of Biochemistry and Molecular Biology, University of Chittagong, Chittagong-4331, Bangladesh.
authors.forename: Md Atiar
authors.initials: MA
authors.lastname: Rahman
authors.forename: Md Saiful
authors.initials: MS
authors.lastname: Islam
mesh_terms: D000818:Animals; D000900:Anti-Bacterial Agents / Q000737:chemistry / Q000494:pharmacology*; D000975:Antioxidants / Q000737:chemistry / Q000494:pharmacology*; D001156:Artemia / Q000187:drug effects; D001713:Biphenyl Compounds / Q000037:antagonists & inhibitors; D004305:Dose-Response Relationship, Drug; D020128:Inhibitory Concentration 50; D019686:Lamiaceae / Q000737:chemistry*; D008826:Microbial Sensitivity Tests; D064209:Phytochemicals / Q000737:chemistry / Q000494:pharmacology*; D010851:Picrates / Q000037:antagonists & inhibitors; D010936:Plant Extracts / Q000737:chemistry / Q000494:pharmacology*; D018675:Toxicity Tests
chemical_list: D000900:Anti-Bacterial Agents; D000975:Antioxidants; D001713:Biphenyl Compounds; D064209:Phytochemicals; D010851:Picrates; D010936:Plant Extracts; C004931:1,1-diphenyl-2-picrylhydrazyl
keywords: Antibacterial; Cytotoxic; Leucas aspera; Probit; Radical scavenging