Antibiogram of Escherichia coli isolated from semi-closed system farmed Asian clam (Corbicula fluminea)

Abstract

In the present study, antibiogram of Escherichia coli isolated from farmed Asian clam, Corbiculafluminea was characterised. Asian clam or locally known as ‘etak’ is processed to became smokedclam and consumed as snack by Kelantanese. However, there are many diarrhoea cases afterconsuming smoked clam. Furthermore, there are also insufficient information about the E.coli levelin Asian clam farm and effective antibiotic in controlling the bacteria in the litereature. Hence, thisstudy was carried out to provide information of antibiogram of E.coli to be reference in the future.Eosin Methylene Blue agar (EMB) was used to isolate E. coli. A total of 100 isolated bacteria weresubjected to antibiotic sensitivity test using disk diffusion method. A total of 18 types of antibioticsnamely novobiocin (30µg/disk), fosfomycin (50 µg/disk), tetracycline (30µg/disk), lincomycin(15µg/disk), flumequine (30µg/disk), sulphamethoxazole (25 µg/disk), amoxycillin (25 µg/disk),chloramphenicol (30 µg/disk), oleandomycin (15 µg/disk), spiramycin (100 µg/disk), ampicillin(10 µg/disk), oxytetracycline (30 µg/disk), doxycycline (30 µg/disk), nalidixic acid (30 µg/disk),florfenicol (30 µg/disk), erythromycin (15 µg/disk), kanamycin (30 µg/disk) and oxolinic acid (2µg/disk). The findings of the present study showed total plate count of E. coli was 6.45 x 103 colonyforming unit (CFU/100g) of sampled Asian clam. Hence, the clam is needed to be under cleansingtreatment before can consider safe for human consumption. Antibiotic results showed 51 % wasrecorded as antibiotic resistance case, 44 % antibiotic sensitive case and 5 % as antibioticintermediary sensitive case. None of the tested antibiotics was successfully inhibited the growth ofthe present bacterial isolates indicating more antibiotics are needed to be screen in the future studyto find out the most effective antibiotic in controlling isolated E. coli.