KARAKTERISTIK DAYA HAMBAT PERTUMBUHAN BAKTERI PERUSAK PANGAN HASIL ISOLASI DARI IKAN NILA (Oreochromis niloticus) OLEH EKSTRAK JAHE (Zingiber officinale ) DENGAN PENGENCER EMULSI TWEEN 80

Abstract

Nile Tilapia is a fish that is easy to get damaged by food microorganism contamination. This study aimed to understand the characteristic of inhibition zone of the ginger extract to bacteria growth that is isolated from Nile Tilapia. This research was a pure experimental with randomized control trial factorial research design that included of 2 factors which were type of bacteries (Staphylococcus saphropyticus, Bacillus alvei, Bacillus licheniformis, and Pseudomonas aeruginosa) and ginger extract concentration (0%, 25%, 35%, dan 45%), each of them was repeated 3 times. The independents variable were type of bacteries and ginger extract concentration and the dependen variable was bacterial growth inhibition zone. This study found that the inhibition zone in every extract concetration from the widest to the narrowest were Staphylococcus saphropyticus, Bacillus alvei, Bacillus licheniformis, and Pseudomonas aeruginosa. Optimum concentration to inhibit the growing of Bacillus alvei and Bacillus licheniformis was 45%.The 25% of extract was effective to inhibit the growth of Staphylococcus saphropyticus and Pseudomonas aeruginosa. To sum up, the strongest inhibition of ginger extract was on Staphylococcus saphropyticus and the weakest was on Pseudomonas aeruginosa. There were significant effects in inhibition zone of bacterial growth that are isolated from Nile Tilapia in every concentration of ginger extract and every species of bacteria.