Isolation and identification of microorganisms involved in Bambangan fermentation

• Main Author: Chin, Seng Yee
• Format: Thesis
• Language: English; English
• Published: 2012
• Subjects: TP248.13-248.65 Biotechnology
• Online Access: https://eprints.ums.edu.my/id/eprint/43757/1/24%20PAGES.pdf; https://eprints.ums.edu.my/id/eprint/43757/2/FULLTEXT.pdf

The objective of this study was to isolate and identify the microorganisms involved in bambangan fermentation, a well accepted indigenous fermented fruit of Sabah. Freshly prepared samples obtained from supplier were kept in ceramic jar (S1) and glass bottles (S2) respectively similar to the conditions of the supplier throughout the fermentation process. Microbiological and chemical analyses were carried out at each interval times. Moisture, ash and protein contents for both samples S1 and S2 increased significantly (p<0.05) during bambangan fermentation. Lactic acid increased notably during the process from 5.0±1.5 mg/g to 108.7±4.8 mg/g (S1) and 5.8±1.8 mg/g to 93.4±2.77 mg/g (S2), which present as the basis of pH reduction in the samples. Amount of glucose, fructose and sucrose were found as 1.35±0.60 mg/g (S1) and 2.5±0.97 mg/g (S2); 39.6±2.12 mg/g (S1) and 36.8±1.18 mg/g (S2); 2.92±1.12 mg/g (S1) and 5.1±1.08 mg/g (S2) at the end of fermentation. Alcohol content in samples S1 and S2 were 1.78±0.20% and 1.91± 0.15% respectively after 10 days of fermentation. A total of 161 microbial isolates were identified throughout the bambangan fermentation. Microbial succession was observed during the bambangan fermentation with the coexist of lactic acid bacteria and yeast, which were believed to stay in a symbiosis correlation in the substrate during fermentation. The imperative microorganisms involved in bambangan fermentation were Lactobacillus plantarum, Pediococcus pentosaceus , Issatchenkia orientalis and Hanseniaspora guillermondii which play important roles in shaping the end product. The variation of microflora during the bambangan fermentation allied with the changes of chemical component in the samples. Among the 32 tested strains, Lactobacillus plantarum (LP1 and LP2); Lactobacillus paracasei spp paracasei (LPSP1) and Issatchenkia orientalis (IO1) were desired as potential probiotic strains among the entire tested strains ever since that they’re capable to withstand at pH3, 0.3% bile salt concentration and performed antimicrobial properties as well. Most of the lactic acid bacteria strains and Issatchenkia orientallis showed significant glycodicidase acivity. The occurrence of a wide diversity of LAB and yeast in fermented bambangan could in part be responsible for the desirable quality attributes associated with the product. Additional study using 16 rDNA sequencing could be carried out in the future to validate the unknown isolates (8%) and facilitate the development of potential starter cultures to upgrade the fermentation process with controllable parameters.