1.Effect of fermentation time on exopolysaccharide production by Weissella confusa isolated from peanut (Arachis hypogaea L.) milk
Anik Ma' ; unatin ; Akyunul Jannah ; Muhammad Ilham Kusuma Winahyu
Malaysian Journal of Microbiology 2024;20(no.1):24-30
Aims:
The aim of this study was to identify an isolate B, an exopolysaccharide (EPS)-producing lactic acid bacteria and determine the fermentation time effect on EPS production.
Methodology and results:
Isolate B, an EPS producer, was isolated from peanut milk containing commercial sugar, which was fermented spontaneously for 24 h. Isolate B was identified biochemically using API 50 CH and molecularly based on 16S rDNA. The effect of fermentation time on EPS production by isolate B with variations of the fermentation time were 12, 24, 36, 48 and 60 h. Isolate B was able to produce EPS qualitatively by producing mucoid colonies on solid media containing sucrose. The identification revealed that this isolate was Weissella confusa both biochemically using API 50 CH and molecularly based on 16S rDNA sequence homology-based method. The fermentation time significantly affected EPS production (P<0.05). Isolate B (W. confusa) produced the highest EPS (10.41 g/L) at 36 h with
a cell viability of 6.5 × 108 CFU/mL. Furthermore, the FTIR results of EPS showed absorption bands characteristic of carbohydrates, including O-H, C-H, C=O, C-O-C and α-1,6 glycosidic groups. The EPS in this study was most likely a dextran type.
Conclusion, significance and impact of study
The yield of EPS production was influenced by fermentation time. Results suggest that W. confusa isolated from peanut milk had a good ability for EPS production. Therefore, it can be considered further to apply this strain for the production of EPS. However, further research is required.