Laboratory of Food Chemistry and Toxicology, Faculty of Pharmacy, University of Valencia, Av. Vicent Andrés Estellés s/n, 46100 Burjassot, Spain.
Food Funct. 2018 Jul 17;9(7):3688-3697. doi: 10.1039/c8fo00535d.
The aim of this study was to evaluate the biological and antimicrobial activities of commercial freeze-dried whey fermented by lactic acid bacteria in order to valorize this high polluting liquid waste of the dairy industry. Freeze-dried whey was fermented by different strains of Lactobacillus plantarum (CECT 220, 221, 748) at three different times of fermentation (24, 48, 72 h). Afterwards, the extract was purified on centricon amicon with a cut-off of 3 kDa to obtain a permeate consisting of small bioactive compounds reported in the literature to show greater bioactivity. The purified and diluted samples were subjected to the biological and antimicrobial tests for the evaluation of antioxidant, antihypertensive, iron binding, and antifungal activities and identification of phenolic compounds. The results highlighted a radical cation scavenging activity ranging from 1.415 to 2.083 mmol trolox equivalents TE per kg of dry weight, a percentage of iron binding capacity ranging between 23-55% and a percentage of ACE inhibitory activity ranging between 67-85%. The optimal biological activity was obtained from whey fermented by L. plantarum 220 for all the assays performed, except for the iron chelating activity. Furthermore, the antifungal analysis showed a good activity against the mycotoxigenic fungi belonging to Fusarium generum (F. moniliformis, F. graminearum and F. verticillioides), while a slight activity was obtained for Aspergillus and Penicillium generum. This antifungal activity could be correlated to the production of phenolic compounds during fermentation. The obtained results support the hypothesis of using whey as a functional ingredient to improve food preservation.
本研究旨在评估商业冻干乳清经乳酸菌发酵后的生物和抗菌活性，以实现对乳制品工业这种高污染废液的增值利用。将冻干乳清分别用三种不同发酵时间（24、48 和 72 小时）的三种不同植物乳杆菌（CECT 220、221 和 748）进行发酵。然后，将提取物通过截留分子量为 3 kDa 的 centricon amicon 进行纯化，以获得一种包含小生物活性化合物的渗透物，这些化合物在文献中报道具有更大的生物活性。纯化和稀释后的样品进行生物和抗菌测试，以评估抗氧化、降压、铁结合和抗真菌活性，并鉴定酚类化合物。结果表明，清除自由基阳离子的活性范围为 1.415 至 2.083mmol trolox 当量 TE/kg 干重，铁结合能力的百分比范围在 23-55%之间，血管紧张素转换酶抑制活性的百分比范围在 67-85%之间。除了铁螯合活性外，在所有进行的测定中，均从由 L. plantarum 220 发酵的乳清中获得了最佳的生物活性。此外，抗真菌分析显示对属于镰刀菌属（F. moniliformis、F. graminearum 和 F. verticillioides）的产真菌毒素真菌具有良好的活性，而对曲霉菌属和青霉菌属则仅显示出轻微的活性。这种抗真菌活性可能与发酵过程中酚类化合物的产生有关。所得结果支持了将乳清用作功能性成分以改善食品保存的假设。
