乳酸菌发酵黑莓汁风味品质及神经保护作用

Flavor Quality and Neuroprotective Effect of Blackberry Juice Fermented with Lactic Acid Bacteria

本研究通过Lactobacillus plantarum P-S1016发酵黑莓汁,测定菌株生长动力学参数,并对黑莓汁有机酸、风味物质和电子舌评分进行分析;以皮质酮为诱导剂建立PC12细胞损伤模型,测定细胞活力、活性氧水平、细胞凋亡率和线粒体膜电位,探究发酵黑莓汁对皮质酮损伤细胞的保护作用。结果表明,L.plantarum P-S1016生长动力学模型拟合度R2为0.943,表明模型拟合良好,29.28 h时菌体浓度达到最大值9.40(lg(CFU/mL));经过发酵黑莓汁中的乳酸和琥珀酸质量浓度分别为38.99 mg/mL和3.30 mg/mL,酯、醇、酸及其他风味成分含量均有增加,醇类物质占比最高(33.28%),其次是烷类(29.80%),黑莓汁的咸味口感明显降低;此外,质量浓度50、200μg/mL的发酵黑莓汁冻干样可显著提高皮质酮诱导下细胞相对存活率,使其提高至(1.48±0.07)倍和(1.60±0.01)倍,降低细胞内活性氧水平、晚期凋亡和坏死细胞占比,抑制线粒体膜电位下降。综上所述,L.plantarum P-S1016可应用于黑莓汁发酵,赋予其更好的口感和风味品质,使其具有更强的神经保护潜力。本研究制得的发酵黑莓汁有望成为新型功能性天然植物基产品,对于提高黑莓鲜果的食用特性与功能价值有一定的现实意义。

In this study,blackberry juice was fermented with Lactobacillus plantarum P-S1016.The growth kinetic parameters of this strain were determined,and the organic acids and flavor substances of fermented blackberry juice were analyzed.Besides,its flavor quality was tested using an electronic tongue(E-tongue).The protective effect of fermented blackberry juice against corticosterone-induced injury in PC12 cells was investigated by measuring cell viability,reactive oxygen species(ROS)level,apoptosis rate,and mitochondrial membrane potential.The results showed that the growth kinetic model of L.plantarum P-S1016 had excellent goodness of fit with a determination coefficient(R2)of 0.943,and the bacterial concentration reached a maximum value of 9.40(lg(CFU/mL))at 29.28 h.The contents of lactic acid and succinic acid in fermented blackberry juice were 38.99 and 3.30 mg/mL,respectively,and the contents of esters,alcohols,acids,and other flavor components increased compared with those in fresh blackberry juice,with alcohols accounting for the highest proportion(33.28%)of the total,followed by alkanes(29.80%);the saltiness of blackberry juice was significantly reduced after fermentation.In addition,fermented blackberry juice at concentrations of 50 and 200μg/mL significantly increased the survival rate of cells induced by corticosterone by(1.48±0.07)and(1.60±0.01)folds,reduced intracellular ROS levels,late apoptosis rate and the proportion of necrotic cells,and inhibited the decrease of mitochondrial membrane potential.In conclusion,blackberry juice fermented with L.plantarum P-S1016 has good taste and flavor quality and strong neuroprotective potential.It is expected to become a new functional natural plant-based beverage,which is important for improving the edible properties and functional value of blackberry fresh fruits.