Valorization of sugarcane bagasse to high value-added xylooligosaccharides and evaluation of their prebiotic function in a synbiotic pomegranate juice

The purpose of the present study was the production of xylooligosaccharides (XOS) from the sugarcane bagasse and evaluation of its prebiotic function in a synbiotic pomegranate juice. The XOS production was done in two steps: optimization of alkaline hydrogen peroxide extraction of xylan followed by the enzyme hydrolysis method by the response surface methodology based on the central composite design (CCD). The structural properties of the extracted xylan were also evaluated by HPLC and FT-IR analyses. The mixed xylooligosaccharides for protecting the prebiotic function of Bifidobacterium animalis Bb-12 in a developed synbiotic pomegranate juice was evaluated. The optimized extraction conditions for xylan via the response surface methodology (RSM) were 5.63 % H2O2, 12.91 % NaOH, and 17.51 h and corresponding to relative yield of xylan at the tune of 95.84 %. The minimum concentration of xylose (3.034 mg/ml) and maximum yield of XOS (5.52 mg/ml) through RSM were achieved at the enzyme dose of 85 U/g, substrate concentration of 3%, and reaction time of 10 h. The generated XOS could increase the viability of the probiotics during 30 days of storage at 4 °C. The prebiotic production of XOS from xylan of bagasse via enzymatic hydrolysis is preferred for the pharmaceutical and food industry applications owing to food safety and consumer awareness. Enzymatic production of XOS could be a suitable solution for the protection of probiotic bacteria in the low acidic environment of pomegranate and other acidic juices or non-dairy synbiotic beverages.