2017 ASHS Annual Conference

The present study was carried out to assess the antimicrobial activity and to determine the zone of inhibition of four herbal essential oils, four weeds extracts and eight bacteria on seven pathogenic bacterial strains. The antimicrobial activity was determined in the oil and extracts using agar well diffusion method. The antibacterial activities of EOs (50 μl) were maximum of clove, cumin, carom (white) and fennel respectively. The results showed that the remarkable inhibition of the bacterial growth was shown against the target organisms. Zone of inhibition were maximum in the case of clove against bacteria Serratia rubidae(19mm) Xanthomonas oryzae (16.6mm), Xanthobacter flavus (16.3mm), Serratia plumethica(15mm), Serratia liquifaicens(13.6mm),Pseudomonas maltophila(13.3 mm). Aqueous extracts of plants (25, 50, and 75 %) were tested against seven pathogenic strains. Zone of inhibition of extracts were compared with that of standard like ampicillin (20mg/ml), for antibacterial activity. Results showed that 75% concentration of Trianthema portulacastrum formed maximum 11.66 mm zone of inhibition against Pseudomonas maltophila and minimum 3.66 mm for Xanthomonas oryzae. Digeria arvensis, parthenium hysterophorus and cyperous rotundus give minimum inhibition zones as compared to Trianthema portulacastrum for all target strains. In vitro screening of test bacteria against target bacterial strains were evaluated. Results with respect to the above mentioned bacteria represented that Azotobacter nigricans formed maximum zone of inhibition (18.6 mm) against Serratia rubidae while (15mm) for Serratia liquifaciens. Kurthia sp. formed (14 mm) zone against Xanthobacter flavus. Xanthomonas oryzae was maximally controlled by the xanthobacterium autotrophicus (12.66 mm).