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196 PROCEEDINGS OF INTERNATIONAL SCIENTIFIC CONFERENCE ON APPLIED BIOTECHNOLOGYon the Gauze I and KA media (Figure 2). In total, 1227 bacterial colonies (strains) were obtained for screening of antagonistic activity against eight tested pathogenic strains, including four Gram-negative bacteria strains (P. putida 3326K1, P. auroginosa ATCC 9027, E. coli ATCC 11105, and S. typhimurium ATCC 14028), three Gram-positive bacteria strains (B. cereus ATCC 11778, S. aureus ATCC 6538, E. aerogenes ATCC 13048), one antibioticresistant Gram-positive bacteria strains (S. epidermidis ATCC 35984) and one yeast strain (C. albicans ATCC 10231). The results showed that 28 strains were capable of antagonizing pathogens from 7 - 34 mm (Table 1). Most of the isolated bacterial strains had antagonistic activity against B. cereus ATCC 11778 (14/28 strains) and E. coli ATCC 11105 (9/28 strains), P. putida 3326K1 and S. aureus ATCC 6538 had the same number of antagonistic strains, two strains, P. auroginosa ATCC 9027 and S. typhimurium ATCC 14028 also had only one antagonistic strain each. No strains were found to be antagonistic against S. epidermidis ATCC 35984 and E. aerogenesATCC 13048 from the isolated bacterial strains. The two strains N2 GII14 and N6 GII4 were determined to have the best antagonistic activity, with antibacterial/antifungal zone diameters > 20 mm, and simultaneously inhibited the two test pathogenic strains (Figure 3).(a) (b) (c)Figure 2. Representative images of bacterial isolation on different media: (a) MA, (b) MI, and (c) Gauze I