Co-fermentation of papaya juice with Lactiplantibacillus plantarum and Saccharomyces cerevisiae enhances the physicochemical properties, antioxidant activity, and bioaccessibility

Fermentation can extend fruit shelf life and enhance fruit products’ quality. This study investigated the effects of co-fermenting with Saccharomyces cerevisiae (SC) and Lactiplantibacillus plantarum (LP) at different ratios (1:0 to 1:10) on the physicochemical, antioxidant, and digestive properties of papaya juice. Co-fermentation reduced pH by 1.12 units and increased titratable acidity by 72.30%. Spectroscopic and HPLC analyses showed that the 1:8 group exhibited 46.33% higher antioxidant power and 20.66% greater polyphenol. These enhancements likely result from synergistic interactions, where LP’s hydrolases mediate polyphenol release, while SC provides nitrogen for LP growth. Following in vitro digestion, the 1:8 group also showed >100% carotenoid bioaccessibility and a 2.68% increase in α-glucosidase inhibitory activity. Molecular docking results further revealed procyanidin B1 and β-carotene exhibited strong binding scores to α-glucosidase, contributing to competitive inhibition. Overall, a 1:8 SC–LP ratio was optimal for papaya juice fermentation, highlighting its potential for functional plant-based beverages.

发酵可延长果实货架期并提升果品质量。本研究探究了酿酒酵母（Saccharomyces cerevisiae, SC）与植物乳杆菌（Lactiplantibacillus plantarum, LP）以不同比例（1:0至1:10）混合发酵对木瓜汁理化特性、抗氧化活性及消化特性的影响。混合发酵可使木瓜汁pH值降低1.12个单位，滴定酸度提升72.30%。光谱分析与高效液相色谱（HPLC）检测结果显示，比例为1:8的发酵组抗氧化活性提升46.33%，多酚含量增加20.66%。上述品质提升可能源于二者的协同互作：LP所产水解酶介导多酚释放，而SC则为LP的生长提供氮源。体外消化实验结果表明，该1:8发酵组的类胡萝卜素生物可及性超过100%，且α-葡萄糖苷酶抑制活性提升2.68%。分子对接实验进一步揭示，原花青素B1与β-胡萝卜素可与α-葡萄糖苷酶形成高结合能复合物，进而发挥竞争性抑制作用。综上，SC与LP以1:8的比例混合发酵为木瓜汁的最优工艺，该结果凸显了其在功能性植物基饮品开发中的应用潜力。