Abstract Poly(vinyl alcohol) (PVA) was investigated as a carrier for Lactobacillus rhamnosus ATCC 7469 cells for application in L-(+)-lactic acid (LA) fermentation on low-cost food industry by-products. Brewer’s spent grain (BSG) and malt rootlets (MR) hydrolysates, with the addition of brewer’s yeast, brewer’s yeast extract, or malt rootlets extract and soy lecithin were evaluated as media for LA fermentation. PVA concentrations of 5, 10 and 15% were evaluated and the optimal concentration was further used. Obtained PVA biocatalyst (BC) was applied in batch and repeated batch fermentations of BSG and MR hydrolysate. During 12 consecutive batch fermentations, the BC showed high mechanical stability and minor loss of activity while achieving high LA yield (97%) and productivity (2.1 g/L h-1). The study suggests that the immobilized L. rhamnosus cells in PVA cryogel can be successfully used in stable repeated batch fermentations on low-cost fermentation media without the loss of cell activity and LA fermentation capability.

中文翻译：

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将鼠李糖乳杆菌封装在聚乙烯醇中用于生产 L-(+)-乳酸

摘要 研究了聚乙烯醇 (PVA) 作为鼠李糖乳杆菌 ATCC 7469 细胞的载体，用于 L-(+)-乳酸 (LA) 发酵低成本食品工业副产品。啤酒糟 (BSG) 和麦芽根 (MR) 水解物，添加啤酒酵母、啤酒酵母提取物或麦芽根提取物和大豆卵磷脂，被评估为 LA 发酵的培养基。评估了 5%、10% 和 15% 的 PVA 浓度，并进一步使用了最佳浓度。获得的 PVA 生物催化剂 (BC) 用于 BSG 和 MR 水解物的分批和重复分批发酵。在连续 12 次分批发酵过程中，BC 表现出高机械稳定性和较小的活性损失，同时实现了高 LA 产量 (97%) 和生产力 (2.1 g/L h-1)。该研究表明，固定的 L.