Isolasi, Karakterisasi dan Identifikasi Bakteri Asam Laktat (BAL) pada Usus dan Lambung Ikan Kembung Lelaki (Rastrelliger kanagurta) yang Didaratkan di Tempat Pendaratan Ikan (TPI) Gabion Belawan

Abstract

Mackerel is a fish that has important economic value. This is because these fish are mostly caught for consumption. So it is necessary to carry out tests on bacteria and analyze bacterial growth in the media used. This research aims to determine the isolation, characterization, identification and growth rate of Lactic Acid Bacteria from the intestines and stomachs of fish and to determine the growth rate of Lactic Acid Bacteria that have been successfully isolated from the intestines and stomach of Male Mackerel fish (Rastrelliger kanagurta) which was landed at the Belawan Gabion Fish Landing Site (TPI). This research was carried out in April - May 2023. The research methods carried out included sampling stages, sample preparation, isolation purification of BAL, morphological analysis, physiological analysis and bacterial growth rate. The results of the research obtained were the discovery of 8 genera of bacteria, namely bacteria in the stomach of the genus Bacillus, Lactobacillus and Sporolactobacillus, bacteria in the intestines of the genus Streptococcus, Bifidobacterium, Weisella, Tetragenococcus and Carnobacterium. Genus Bacillus with a growth rate of 0.601– 0.687 bacteria/minute generation time 0.94–1.15 generations/minute, Streptococcus growth rate 0.366–0.499 bacteria/minute and generation time 1.38–1.89 generations/minute, Lactobacillus growth rate 0.708–0.823 bacteria/minute and generation time 0.73–097 generations/minute, Bifidobacterium growth rate 0.499– 0.577 bacteria/minute and generation time 1.19–1.50 generations/minute, Weisella growth rate 0.383–0.472 bacteria/minute and generation time 1.46–1.80 generations/minute, Tetrargenococcus, Carnobacterium growth rate 0.451–0.623 bacteria/minute and generation time 1.11–1.53 generations/minute, Sporolactobacillus growth rate 0.549–0.638 bacteria/minute and generation time 1.08–1.26 generations/minute. Characteristics and biochemical tests, namely arrangement (streptobacilli) as many as 41 isolate, shape (filamentous) as many as 4 isolate, elevation (convex) as many as 36 isolate, edges (filamentous) as many as 3 isolate, color (milk white) as many as 35 isolate, positive gram staining test (+) as many as 50 isolate and negative gram staining test (-) was 10 isolate, motility (+) was 58 isolate and motility (-) was 2 isolate, MR (+) was 43 isolate and (-) was 17 isolate, VP (-) was 60 isolate, catalase (-) was 60 isolate , S/B (A/K) 41 isolate and S/B (A/A) 6 isolate S/B (K/A) 1 isolate SB (K/K) 2 isolate, and gas (-) as much as 60 isolate