Division of Research Development and Education, National Institute of Chemical Safety (NICS), Ministry of Environment, Daejeon 34111, Republic of Korea.
Department of Food Science, Gyeongnam National University of Science and Technology, Jinju 52725, Republic of Korea.
J Food Drug Anal. 2018 Jul;26(3):1054-1065. doi: 10.1016/j.jfda.2017.12.003. Epub 2018 Jan 17.
This research was the first to demonstrate changes in nutritional compositions (isoflavone and CLA) from the 50% methanol extracts of soy-powder milk (SPM) and soy-powder yogurt (SPY) through fermentation using Lactobacillus plantarum S48 and P1201 strains. The radical scavenging activities and protective effects against oxidative stress in LLC-PK cells were also investigated. The average physicochemical characteristics including acidity and viable cell number as well as β-glucosidase activity increased with 0.2 → 0.7%, 7.5 → 9.8 log cfu/mL, and 0.0 3 → 1.75 U/g in SPYs. Total average isoflavones were considerably reduced (3180.3 → 2018.3 μg/g) with the increase of aglycone contents (191.8 → 770.2 μg/g), especially, daidzein exhibited the most remarkable increase rate (98.6 → 460.9 μg/g; > 4.8 times) during fermentation. The CLA and total phenolics also increased with significant differences (ND → 1.6 mg/g; 2.4 → 3.6 mg/GAE/g) between SPM and SPY. Interestingly, the cis-9, trans-11 CLA showed approximately 90% in total content. Moreover, the scavenging capacities against three radicals markedly increased with about 30% in SPYs, as the following order: ABTS > hydroxyl > DPPH. The protective effects on oxidative stress (pyrogallol: O, SNP: NO, and SIN-1: ONOO) were also observed high cell viabilities (>10%) under LLC-PK cellular system. Our results suggest that SPY may be utilized as a potent source regarding natural antioxidants and beneficial components for health food and medical uses.
这项研究首次证明了通过使用植物乳杆菌 S48 和 P1201 菌株发酵，大豆蛋白粉牛奶（SPM）和大豆蛋白粉酸奶（SPY）的 50%甲醇提取物中的营养成分（异黄酮和 CLA）发生了变化。还研究了 LLC-PK 细胞的自由基清除活性和抗氧化应激保护作用。随着 SPY 中酸度和活菌数以及β-葡萄糖苷酶活性从 0.2→0.7%、7.5→9.8 log cfu/mL 和 0.03→1.75 U/g 的增加，其平均理化特性也得到了提高。总异黄酮含量显著降低（3180.3→2018.3μg/g），同时糖苷含量增加（191.8→770.2μg/g），特别是在发酵过程中，大豆苷元的含量增加最为显著（98.6→460.9μg/g；增加了>4.8 倍）。CLA 和总酚类物质也有所增加，且 SPM 和 SPY 之间存在显著差异（ND→1.6mg/g；2.4→3.6 mg/GAE/g）。有趣的是，顺式-9、反式-11 CLA 的总含量约为 90%。此外，在 SPY 中，三种自由基的清除能力显著提高，约为 30%，顺序为：ABTS>羟基>DPPH。在 LLC-PK 细胞系统中，还观察到对氧化应激（焦儿茶酚：O、SNP：NO 和 SIN-1：ONOO）的保护作用，细胞活力均>10%。我们的研究结果表明，SPY 可作为一种潜在的天然抗氧化剂和有益成分的来源，用于保健食品和医疗用途。
