Jornal Europeu de Biologia Experimental Acesso livre

Abstrato

Effect of increasing concentration of antimicrobial agent on microbial load and antibiotic sensitivity pattern of bacterial isolates from vegetables

Daniel NA Tagoe and ObedA Aning

Research has shown fresh vegetables to promote good health as well asharbour a wide range of microbial contaminants.The study assessesthe effect of increasingconcentration of antimicrobial agent (vinegar solution) on the microbial load as well as the Antibiotic Sensitivity Pattern of bacterial isolates on vegetables sold in the Cape Coast Municipality, Ghana. Ten different vegetables were sampledof which 10g of a batch each was washed with 50ml concentration each of vinegar solution of 10%, 20% and 30%. Serial dilution and aerobic colony counting was performed by pour plating on PCA (Plate Count Agar) for each sample and concentration. Isolates were identified by standard biochemical methods whilstthe disc diffusion technique was applied in Antibiotic Susceptibility Testing of each bacterial isolate.The mean microbial load ranged from highest of 2.47×108CFU/ml using 10% vinegar to the least 1.45×107CFU/ml washing with 30% vinegar solution.Total microbial counts significantly decreased (P<0.001) with increasing vinegar concentration andin comparison with control (distilled water washing 3.26×1010). Eight different bacteria species were isolated of which B. cereus (36.25%), was the highest whilst Micrococcus spp.,P.aeruginosaandKlebsiellaspp. were the least (2.5%). Proteus spp. and L. monocytogenes were highly resistant (75%) whilst the least resistant organism was Micrococcus spp. (25%). Gentamicin and Amikacin where the most effective (100%) antibioticswhilst Ampicillin was the least effective (12.5%).Increased vinegar concentration has the tendency to reduce microbial loads on vegetables and thus its application is recommended.