荔枝汁-大豆蛋白培养基鼠李糖乳杆菌发酵过程脂肪酸组的变化动态

Dynamic of fatty acid group during fermentation of Lactobacillus rhamnosus in the medium of lychee juice and soybean protein

中文关键词:  鼠李糖乳杆菌  荔枝汁  大豆蛋白  发酵  脂肪酸组

英文关键词:Lactobacillus rhamnosus  litchi juice  soybean protein  fermentation  fatty acid group

中文摘要:

      目的 解析荔枝汁-大豆蛋白培养基鼠李糖乳杆菌发酵过程脂肪酸组的变化动态。方法 利用气相色谱-质谱 (gas chromatography–mass spectrometry, GC-MS)脂肪酸自动测定仪, 分析植物原料荔枝汁、大豆蛋白(豆浆)、荔枝汁+大豆蛋白(体积比为1:1)培养基的脂肪酸组成, 以及鼠李糖乳杆菌FJAT- 13807(Lactobacillus rhamnosus FJAT-13807)发酵前后和发酵过程脂肪酸组的变化。结果 荔枝汁-大豆蛋白复合培养基经过鼠李糖乳杆菌FJAT- 13807发酵脂肪酸组成发生显著变化(P < 0.05), 发酵前脂肪酸标记30条, 发酵后上升到53条, 增加了76.77%, 脂肪酸总量增加115.01%; 脂肪酸标记可分为高含量(2条)、中含量(10条)和低含量(41条)3组, 其中高含量组的脂肪酸标记C16:0和C18:1 ω9c, 含量占比超过45%, 具有乳杆菌种属特征; 鼠李糖乳杆菌FJAT- 13807发酵过程中, 脂肪酸组和活菌数变化趋势相近; 发酵1 h, 活菌数达8.7×107 CFU/mL, 此时, 脂肪酸总量达1426116(响应值); 发酵1~6 h, 活菌数略有下降, 为6.20×107 CFU/mL, 脂肪酸总量相应下降为1106592(响应值); 发酵6~12 h, 活菌数含量急速上升到高峰56.00×107 CFU/mL, 相应的脂肪酸总量也急速上升到2349101(响应值)。结论 乳杆菌发酵能显著增加脂肪酸组的种类和含量, C16:0和C18:1 ω9c为乳杆菌种属特征脂肪酸标记, 可通过检测脂肪酸总量的变化, 可以监测乳杆菌数量变化动态。

英文摘要:

      Objective To analyze the dynamic of fatty acid group during fermentation of Lactobacillus rhamnosus in the medium of lychee juice and soybean protein. Methods Gas chromatography–mass spectrometry(GC-MS) fatty acid automatic analyser was used to analyze fatty acid profiles of plant materials of litchi juice, soybean protein (soya-bean milk) and litchi juice + soybean protein (V:V=1:1), as well as that of Lactobacillus rhamnosus FJAT-13807) before and after fermentation. Results The fatty acid profiles of litchi juice-soybean protein complex culture medium was significantly changed by Lactobacillus rhamnosus FJAT-13807 (P<0.05). Thirty fatty acid biomarkers were labeled before fermentation of Lactobacillus rhamnosus FJAT-13807 in the litchi juice-soybean protein composite medium, and 53 after fermentation, increasing by 76.77%, and the total fatty acids increased of 115.01%. The fatty acid biomarkers could be divided into three groups of the high content group with 2 biomarkers, middle content group with 10 biomarkers and low content group with 41 biomarkers. The high content group contained 2 fatty acid biomarkers C16:0 and C18:1 ω9c, the content of which accounted more than 45% of the total fatty acids, and had the characteristics of lactobacillus species. During the strain FJAT-13807 fermentation, the change trend of the fatty acid group and the number of viable bacteria was similar. After fermentation for 1 h, the number of viable bacteria reached 8.7×107 CFU/mL, simultaneously the total amount of fatty acids reached 1426116 (response). Fermented for 1-6 h, the number decreased slightly to 6.20×107 CFU/mL, at the same time, the total fatty acid reduced to 1106592 (response). Fermented for 6–12 h, the number increased rapidly to the peak of 56.00×107 CFU/mL, and the total fatty acid also increased rapidly to 2349101 (response). Conclusion The fermentation of Lactobacillus rhamnosus could increase the species and content of fatty acid group. C16:0 and C18:1 ω9c were the characteristics fatty acid markers of lactobacillus species and by detecting the change of total fatty acids, the dynamic change of Lactobacillus quantity can be monitored.