Antimicrobial activity of six different plant extracts against clinical isolates of Staphylococcus spp. from milk origin

Abstract

Two aqueous and four methanolic extracts from six Indian medicinal plants, which are known for its antibacterial activity, were investigated for their ability to inhibit clinical isolates of Staphylococcus spp. from milk origin. The antibacterial activity of the extracts against Staphylococcus spp. was evaluated by Disk diffusion method and Minimum Inhibitory Concentration (MIC). The plant extracts from Piper nigrum (seed), Kigali pinnata DC. (fruit), Azadirchata indica (leaves), Cymbopogon citrates (leaves), Tagetes erecta (leaves) and Emblica officinalis Gaertn. (fruit) showed antibacterial activity with an inhibition zone size of 8.10±0.40 mm, 10.02±0.19 mm, 9.98±0.21 mm, 10.60±0.15 mm, 12.02±0.14 mm and 7.71±0.12 mm, respectively against all the isolates. The antibacterial potency of plant extracts was determined in terms of MIC by the micro broth dilution method. The extracts from the leaves of Tagetes erecta showed better activity against all the isolates followed by Cymbopogon citratus, Kigellia pinnata DC., Azadirachta indica, Piper nigrum and Emblica officinalis Gaertn., respectively. MIC and Minimum Bactericidal Concentration (MBC) values, of the plant extracts, ranged from 16.96±0.00 to 200.00±0.00 mg/ml and 22.32±0.00 to 257.14±0.00 mg/ml respectively, against all the isolates. According to the results of the current investigation, each extract exhibited antibacterial activity and offers hope for the creation of novel drugs with significant biomedical applications and may be investigated further to identify its bioactive component.