臺灣博碩士論文加值系統

於試管中測定乳酸菌降低膽固醇的能力，共使用 19 株菌包括
Bifidobacterium longum B6 和 15708、Lactobacillus acidophilus B
、E、Farr、LA-1、N-1 和 4356、Lactobacillus bulgaricus Lb、448
、449、1006、11842 和 12278 及 Streptococcus thermophilus MC
、573、821、3641 和 19987。所測試的菌株皆具有降低膽固醇的能力。
在含有牛膽鹽的培養下，L. bulgaricus 449 具有最高的降低膽固醇能力
，L. acidophilus 4356 也具有相當好的降低膽固醇能力，膽固醇降低的
程度分別達到 51 % 和 41 %。沒有特定的菌屬或菌種表現出較其他菌屬
或菌種有較高的膽固醇降低能力。本實驗同時探討於試管中膽固醇降低之
機制。雖然膽固醇的降低與去結合型膽鹽共同沈澱有關，但實驗結果顯示
當以牛磺膽酸作為膽鹽來源時，膽固醇也會被降低，因此當膽鹽存在時，
膽固醇的降低除了由於與去結合型膽鹽產生共同沈澱外，也歸因於乳酸菌
細胞的作用。

Nineteen strains of lactic acid bacteria including
Bifidobacterium longum B6 and 15708, Lactobacillus acidophilus
B, E, Farr, LA-1, N-1, and 4356, Lactobacillus bulgaricus Lb,
448, 449, 1006, 11842, and 12278, and Streptococcus thermophilus
MC, 573, 821, 3641, and 19987 were investigated for cholesterol
reducing ability in vitro. Most of the strains tested were able
to reduce cholesterol. L. bulgaricus 449 demonstrated the best
cholesterol reducing ability when oxgall was present. L.
acidophilus 4356 also reduced cholesterol very well when oxgall
was used. These two strains reduced cholesterol at 51 and 41 %,
respectively. No particular genus or species showed higher
cholesterol reducing ability than the others. The mechanisms of
cholesterol reduction were also identified in the in vitro
system. Although the coprecipitation of cholesterol with
deconjugated biles contributed to the reduction of cholesterol
levels, cholesterol was reduced when taurocholic acid was used
as the source of bile. Therefore, the cholesterol reduction in
the presence of bile does not attribute only to the
coprecipitation with deconjugated bile salts but also to the
assimilation by cells.