Evaluation of some biological activities of Trigonella hamosa aerial parts

The antimicrobial activity of T. hamosa aerial parts extract against Bacillus subtilis, Staphylococcus aureus, Enterococcus fecalis, Escherichia coli, Pseudomonas auregenosa, Candida albicans, Fusarium sp. and Aspergilus niger was evaluated by disc diffusion method. The minimum inhibitory concentrations (MICs) for susceptible test microorganisms were further determined. Also the antioxidant and α-amylase inhibition activities were investigated. The extract exhibited antimicrobial activity against C. albican, B. subtilis and E. fecalis; the MICs were 5.5, 7 and 8.5 mg/ml, respectively. Antioxidant and α-amylase inhibition activities of the extract were concentration dependent and the IC50 values were 0.19 and 35 mg/ml, respectively. Thin layer chromatography (TLC) bioautography was used to detect the bioactive fractions of the extract. It revealed that three different fractions of different polarities exhibited antimicrobial, α-amylase inhibition and antioxidant activities. The toxicity of the extract to brine shrimp (Artemia salina) larvae was assessed and the LC50 was found to be 2.3 mg/ml. This study suggests that the extract of T. hamosa aerial parts could be a source of bioactive compounds of different biological activities and is safe in terms of toxicity level.   Key words: Trigonella hamosa, antimicrobial, antioxidant, α-amylase, toxicity.