Department of Soil, Plant and Food Science, Via G. Amendola 165/a, 70126, University of Bari Aldo Moro, Bari, Italy.
Giuliani S.p.A., Via Palagi 2, 20129, Milan, Italy.
Food Microbiol. 2017 Aug;65:25-35. doi: 10.1016/j.fm.2017.01.019. Epub 2017 Feb 1.
This study aimed at using grape marc for the growth of lactic acid bacteria and bifidobacteria with the perspective of producing a functional ingredient having antioxidant activity. Lactobacillus plantarum 12A and PU1, Lactobacillus paracasei 14A, and Bifidobacterium breve 15A showed the ability to grow on grape marc (GM) based media. The highest bacterial cell density (>9.0 CFU/g) was found in GM added of 1% of glucose (GMG). Compared to un-inoculated and incubated control fermented GMG showed a decrease of carbohydrates and citric acid together with an increase of lactic acid. The content of several free amino acids and phenol compounds differed between samples. Based on the survival under simulated gastro-intestinal conditions, GMG was a suitable carrier of lactic acid bacteria and bifidobacteria strains. Compared to the control, cell-free supernatant (CFS) of fermented GMG exhibited a marked antioxidant activity in vitro. The increased antioxidant activity was confirmed using Caco-2 cell line after inducing oxidative stress, and determining cell viability and radical scavenging activity through MTT and DCFH-DA assays, respectively. Supporting these founding, the SOD-2 gene expression of Caco-2 cells also showed a lowest pro-oxidant effect induced by the four CFS of GMG fermented by lactic acid bacteria and bifidobacteria.
本研究旨在利用葡萄渣作为生产具有抗氧化活性的功能性成分的生长基质，用于培养乳酸菌和双歧杆菌。植物乳杆菌 12A 和 PU1、副干酪乳杆菌 14A 和短双歧杆菌 15A 均显示出在基于葡萄渣（GM）的培养基上生长的能力。在添加 1%葡萄糖的 GM 中（GMG），发现细菌细胞密度最高（>9.0 CFU/g）。与未接种和孵育对照发酵的 GMG 相比，GMG 中的碳水化合物和柠檬酸减少，而乳酸增加。样品之间的几种游离氨基酸和酚类化合物的含量存在差异。基于模拟胃肠道条件下的生存能力，GMG 是乳酸菌和双歧杆菌菌株的合适载体。与对照相比，发酵 GMG 的无细胞上清液（CFS）在体外表现出显著的抗氧化活性。通过诱导氧化应激后使用 Caco-2 细胞系进行验证，并分别通过 MTT 和 DCFH-DA 测定法确定细胞活力和自由基清除活性，证实了这一结果。支持这些发现，Caco-2 细胞的 SOD-2 基因表达也显示出由乳酸菌和双歧杆菌发酵的四种 GMG 的 CFS 引起的最低促氧化剂效应。
