大豆發酵乳對人體之腸胃菌叢及血脂之影響
The Effects of Fermented Soymilk on Human Gut Microflora and Blood Lipids
中文摘要
本研究目的在於探討大豆發酵乳是否有益於人體腸道益生菌生長，及對血脂方面 是否具正面功效。第一部份為腸道菌叢研究，篩選無腸胃道方面的疾病及其他健 康問題者，年齡介於 21 至 26 歲，性別不拘，共 26 位，以交叉實驗及自體比 較方式進行，為期八週，前兩週為排空期，接著兩週為實驗第一期，其後兩週為 排空期，接著兩週為實驗第二期。受試者隨機分為兩組：YuSoy 組在第一期飲 用大豆發酵乳，第二期飲用未發酵豆漿；而 SoyYu 組第一期飲用未發酵豆漿，
第二期飲用大豆發酵乳 (每日攝取 500 mL 飲料)。收集糞便進行微生物活菌數 檢測。結果發現飲用大豆發酵乳兩週後，受試者檢體中 Bifidobacterium spp. 及 Lactobacillus spp. 與總厭氧菌之比值，比飲用豆漿後顯著增加 (p < 0.05)，
Clostridium perfringens 比飲用豆漿後活菌數顯著下降 (p < 0.05)。第二部份為血 脂研究，篩選血脂部分偏高之受試者，年齡介於 20 至 55 歲，性別不拘，共 18 位。實驗前兩週為穩定期，接著六週為實驗期，之後兩週為恢復期，實驗期間每 天攝取大豆發酵乳 500 mL，於實驗期第零、二、四及六週取得空腹八小時血液 進行生化分析，並於實驗期第零及及六週取得在飲用大豆乳酸飲料三小時後之血 液進行血漿異黃酮素分析。結果發現，血清低密度脂蛋白膽固醇 (LDL-C) 顯著 降低 (p < 0.05)，三酸甘油酯濃度 (大於 160 mg/dL 之受試者) 顯著降低 (p <
0.05)，高密度脂蛋白膽固醇濃度 (小於 40 mg/dL 之受試者) 顯著增加 (p <
0.05)，而總膽固醇無顯著差異。在抗氧化指標方面，血漿總抗氧化力、紅血球中 麩胱甘?濃度與超氧歧化?活性顯著增加 (p < 0.05)，紅血球中觸?活性無差異性，
而血漿脂質過氧化物濃度顯著減少 (p < 0.05)，LDL 氧化延遲時間顯著延長 34 min (p < 0.05)。本篇證實飲用大豆發酵乳可增加腸道益生菌及降低有害菌之量，
而飲用六週後則可促進體內抗氧化力並降低脂質過氧化物含量，對血脂濃度具有 正面功效，因此大豆發酵乳對人體具有益處。
英文摘要
The objective of this study was to investigate the effects of fermented soymilk on human gut microflora and blood lipids. In section one, a cross-over clinical and self-controlled study was performed, in which 26 subjects (21-26 years of age) were randomly divided into two groups. The subjects in the YuSoy group (n = 13) drank fermented soymilk in the first experimental period, while the subjects in the SoyYu group (n = 13) drank soymilk in the first experimental period. Each subject consumed 500 mL of soy drink a day. After two weeks, in the period of fermented
soymilk-drinking, the ratios of Bifidobacterium spp. to total anerobic organisms and Lactobacillus spp. to total anerobic organisms significantly increased when compared to those in the soymilk-drinking period (p < 0.05). The population of Clostridium perfringens significantly decreased when compared to those in the soymilk-drinking period (p < 0.05). In section two, a 6-wk clinical and self-controlled study was
performed, in which 18 subjects (20-55 years of age) consumed 500 mL of fermented soymilk a day. Blood samples were collected. Blood lipids and antioxidative indexes were measured. After fermented soymilk consumption, the concentration of
LDL-cholesterol significantly decreased (p < 0.05), and the concentration of
triglycerides in those whose > 160 mg/dL significantly decreased (p < 0.05), and the concentration of HDL-cholesterol in those whose < 40 mg/dL significantly increased (p < 0.05). There was no difference in cholesterol. On the other hand, the
concentration of plasma total antioxidant status and glutathione of RBC significantly increased (p < 0.05), while the superoxide dismutase activity significantly increased (p < 0.05). There was no difference in catalase activity of RBC. The thiobarbuturic acid reactive substrance (TBARs) significantly decreased, and the LDL-lag time significantly increased (p < 0.05). These findings indicated that fermented soymilk consumption significantly improved probiotic counts in the human gastrointestinal tract in a two-week period, while the antioxidative condition was improved in a six-week period.
