Although probiotics have been shown to improve health when consumed, recent studies have reported that they can cause unwanted side effects due to bacterial-human interactions. Therefore, the importance of prebiotics that can form beneficial microbiome in the gut has been emphasized. This study isolated and identified bacteria capable of producing biopoymer as a candidate prebiotic from traditional fermented foods. The isolated and identified strain was named WCYSK01 (Wissella sp. strain YSK01). The composition of the medium for culturing this strain was prepared by dissolving 3 g K2HPO4, 0.2 g MgSO4, 0.05 g CaCl2, 0.1 g NaCl in 1 L of distilled water. The LMBP(low molecular weight biopoymers) produced when fermentation was performed with sucrose and maltose as substrates were mainly consisted of DP3 (degree of polymer; isomaltotriose), DP4 (isomaltotetraose), DP5 (isomaltopentaose), and DP6 (isomaltoheptaose). The optimization of LMBP (low molecular weight of biopolymer) production was performed using the response surface methodology. The fermentation process temperature range of 18 to 32oC, the fermentation medium pH in the range of 5.1 to 7.9. The yield of LMBP production by the strain was found to be significantly affected by q fermentation temperature and pH. The optimal fermentation conditions were found at the normal point, and the production yield was more than 75% at pH 7.5 and temperature of 23oC.

Abstract
1. Introduction
2. Materials and methods
    2.1. Fermentation medium preparationand reagents
    2.2. Isolation and identification of strainsfrom fermented kimchi
    2.3. The optimization of LMBP fermentation
    2.4. Batch fermentation for LMBPfermentation
    2.5. Analysis of low molecular weight ofbiopolymer
3. Results and Discussion
    3.1. Isolation of strains
    3.2. Structural Characteristics of LMBPProduced by WCYSK01
    3.3. Optimization of LMBP fermentation
    3.4. Effect of fermentation temperatureand time by WCYSK01 strain onLMBP production
    3.5. The contour and 3 D surface of LMBPfermentation production profilederived from response surfacemethodology
    3.6. Fermentation of LMBP production byWCYSK01 strain in a prototype pilotplant fermentor
4. Conclusion
References

• Hyun Ah Cho(Department of Industry Convergence Engineering, Soonchunhyang University, Chungchungnam-do)
• Nam Chul Kim(Research Institute of Natural Well Food Company, Chungchungnam-do)
• Sun Kyun Yoo(Research Institute of Natural Well Food Company, Chungchungnam-do) Corresponding author