Studies on immunostimulating ability and active components in lactic acid bacteria used to fermented milk

L.德氏保加利亚乳杆菌和嗜酸乳杆菌经溶菌酶和N-乙酰神经氨酸酶水解后进行了表征。为了评价L.嗜酸乳杆菌群乳酸菌能在肠道内生长，L.嗜酸乳杆菌和L.在小鼠腹膜巨噬细胞培养物中研究Gasseri。9株L.嗜酸乳杆菌菌株诱导巨噬细胞培养物中的干扰素。L. 13个菌株中有5个菌株还形成了gasseri。用抗干扰素血清诱导产生的干扰素以α/β型为主。使用小鼠脾细胞通过促有丝分裂活性评价嗜酸乳杆菌菌株。仅在一个完整细胞中观察到较高的活性，然而，来自6个菌株的细胞壁组分显示出显著较高的活性。通过离子交换色谱法分离显示最高值的一个菌株的细胞壁组分，然后测量活性并进行化学分析。该活性主要存在于结合组分中，并且证实其对小鼠脾细胞的B细胞具有特异性。活性组分的糖部分由葡萄糖、N-乙酰氨基葡萄糖、N-乙酰胞壁酸和甘油组成。活性组分中N-乙酰氨基葡萄糖的含量越高，其与葡萄糖的比例越高。当摄入含有这种乳酸菌的乳制品时，嗜酸乳杆菌群可以作为肠道中的免疫刺激剂。

The cell wall components of L. delbrueckii subsp. bulgaricus and L.acidophilus were characterized after hydrolysis with lysozyme and N-acetylneuraminidase. The difference between two species were elucidated.In order to evaluate the biological activity induced by L. acidophilus group lactic acid bacteria which can grow in intestinal tract, induction of interferon by L. acidophilus and L. gasseri was investigated in murine peritoneal macrophage cultures. Four strains in 9 L. acidophilus strains induced interferon in macrophage cultures. Such activation effect by L. gasseri was also formed on 5 strains in 13 strains. Induced interferons were characterized as alpha/beta by treatment with anti-interferon serum.The biological activities of whole cell and hydrolyzed cell component of 9 L. acidophilus strains were evaluated by mitogenic activities using murine spleen cells. Higher activity was observed in only one whole cell, however, the cell wall components from 6 strains showed significantly higher activity. The cell wall component from one strain which showed the highest value was fractionated by ion-exchange chromatography, followed by measurement of the activity and chemical analysis. The activity was mainly found in the bound fractions and it was confirmed to be specific on B-cell of murine spleen cells. Carbohydrate moiety of the active fractions was composed of glucose, N-acetylglucosamine, N-acetylmuramic acid and glycerol. Higher active fraction tends to contain higher N-acetylglucosamine in the ratio against glucose.The results indicate that some strains of L. acidophilus group can act as an immunostimulators in the intestinal tract when dairy products containing such lactic acid bacteria was ingested.