Synergistic potential of agrobiomass-derived xylooligosaccharides (XOS) and antioxidants as pioneering prebiotics for probiotic cultivation

Prebiotic resources, such as xylooligosaccharides (XOS), which are resistant to acidity and temperature, can be derived from lignocellulosic agrobiomass. Hydrolysates containing prebiotic XOS were produced from fruit, rice, and sugarcane biomass using acid and hydrothermal pretreatments. Phosphoric acid pretreatment showed greater potential for biomass breakdown and oligosaccharide release. FTIR analysis detected xylan and pectin in the pellets produced by precipitating the hydrolysates of mango peel (MP), pineapple peel (PP), rice bran (RB) and sugarcane leaf (SCL). The hydrolysate and the precipitate presented different XOS (xylobiose and xylotetraose) profiles and were more than twofold greater in the PP, RB, and SCL pellets (71.28, 109.55, and 188.48 mg/mL, respectively) than in the MP pellets (0.29 mg/mL). SCL hydrolysate, as a carbon source, promotes probiotic growth but is unsuitable for pathogen growth. Furthermore, fermenting the spray-dried SCL hydrolysate powder with probiotics (Bacillus subtilis and lactic acid bacteria) significantly increased its phenolic (236.07 µg GAE/mL) and flavonoid (2.75 mg QE/mL) contents and antioxidant activity (75.77 %). This study highlights the potential for a synergistic interaction between XOS and bioactive compounds, which may considerably benefit probiotics and their hosts. This research demonstrates an efficient and straightforward method for producing XOS, yielding prebiotics at 189.72 g/kg of biomass. This approach provides a viable alternative for the development of plant-based, value-added food products.