Isolate Characterization and Amylolytic Properties of Lactic Acid Bacteria from Traditional Fermented Dadih

Abstract

This research aimed to explore, isolate, select, and characterize lactic acid bacteria (LAB) potentially used as amylolytic bacteria from traditional fermented food "dadih". Dadih was collected from Lareh Sago Halaban and Lintau, West Sumatera Province. The LAB was isolated by the streak method to obtain a uniform color and size colonies. The selected isolates were characterized by the reaction gram and catalase test. The result showed that isolates had the form of coccus, coccobacillus, and basil with gram-positive, catalase-negative, and endospore-negative reactions. The further characterization using the KIT API 50 CHL identified Lactobacillus plantarum (mH1), Lactobacillus paracasei ssp paracasei (mL3), Lactobacillus plantarum (mH4), Lactococcus lactis subsp lactis (mH6), Lactobacillus plantarum (mH7), Lactobacillus plantarum (mH8), Lactobacillus brevis (mH13), and Lactobacillus paracasei subsp paracasei (mL14). The amylolytic and starch hydrolysis test showed that the isolates with higher amylolytic index ≥2 were Lactobacillus paracasei ssp paracasei mL3, Lactobacillus plantarum mH4, and Lactobacillus paracasei ssp paracasei mL14. The Lactobacillus plantarum mH8 had a lower amylolytic index of 0.7. Therefore, the four isolates (mL3, mH4, mL14, and mH8) are potentially used as fermenting bacteria for high- carbohydrate food.