Isolation and identification of lactic acid bacteria from different stages of traditional Malaysian tempeh production

ABSTRACT

Aims: There are many methods of soybean tempeh production as they vary according to the producers. Isolation of lactic acid bacteria (LAB) from tempeh was carried out at different stages of the tempeh production to examine the occurrence of LAB and to identify the isolates. Methodology and results: Morphological, physiological and chemical characteristics with the use of API 20 Strep, API 50 CHL kit and 16S rRNA gene sequences were employed to identify LAB. By using API 20 Strep and API 50 CHL kit, fourteen LAB were obtained and twelve isolates have been successfully identified: seven coccus LAB isolates as Enterococcus faecium, four cocci-bacilli as Leuconostoc mesenteroides ssp. mesenteroides, one bacilli as Lactobacillus delbrueckii ssp. delbrueckii. Meanwhile, two bacilli isolates were categorised as unidentified strain. On the other hand, molecular identification using 27f and 1429r primer had revealed that L. mesenteroides and L. delbrueckii were identified as Leuconostoc lactis and Leuconostoc sp. respectively. Whereas, two previously unidentified bacilli isolates were identified as Alicyclobacillus sp. Conclusion, significance, and impact of study: This result shows that various types of LAB was detected at every stages of tempeh production and had been identified by using two different techniques. The unique characteristics of LAB offer their potential towards food and pharmaceutical industry.