乳酸菌素片生产菌菌株特性及产酸条件的研究

对乳酸菌素片生产菌嗜酸乳杆菌菌株的某些特性如质粒、抗药性、遗传稳定性、β－半乳糖甘酶含量以及产酸条件进行了研究。最佳产酸条件为２０％脱脂乳,自然ｐＨ,３７℃发酵７２ｈ,产酸４４３°Ｔ。     

Accumulation of Uridinediphospho-N-acetylmuramyl-peptides Induced by Glycine and Penicillin

The genes POX2 and POX4, which encode the subunits (PXP-2 and PXP-4) of peroxisomal fatty acyl-coenzyme A oxidase of Candida tropicalis, were introduced into the related yeast Candida maltosa. The cells transformed with POX2 or POX4 gave much PXP-2 or PXP-4 in the purified peroxisomes. The polypeptides associated with the heterologous organelle were resistant to added protease, implying that they were transported into the peroxisomes. Genes for curtailed versions of PXP-4 were constructed in vitro and introduced into the host cells. Peptide-C, the COOH-terminal two-thirds of PXP-4, was efficiently transported into the host peroxisomes, and the polypeptide containing the NH₂-terminal one-third was also, in much lesser amount. These and other results suggested that there were at least two regions of peroxisomal targeting information in PXP-4 and the primary information was internal. The deletions in Peptide-C inhibited the transport of many, but not all, of the host-cell peroxisomal polypeptides. This suggested heterogeneous transport systems on the peroxisomal membrane.     

嗜酸乳杆菌发酵上清液对常见肠道致病菌及其L型抑菌作用的实验研究

目的 探讨嗜酸乳杆菌（L. acidophilus）对肠道致病菌及其L型菌的抑菌作用,为临床开发L. acidophilus活菌制剂提供实验依据。方法 采用肉汤稀释法,检测L. acidophilus 36 h发酵上清液对肠道致病菌及其L型菌吸光度值的影响,计算抑菌率,探讨乳杆菌的抑菌活性。结果 3个浓度的L. acidophilus发酵上清液对3种常见肠道致病菌（致病性大肠埃希菌、伤寒沙门菌、痢疾志贺菌）及其L型菌均有不同程度抑菌作用,其中原液浓度抑菌作用最强。结论 L. acidophilus是一种可用于治疗多种肠道致病菌及其L型菌感染引起肠道疾病的微生态制剂,其代谢产物发挥抑菌作用是其机制之一。     

嗜酸乳杆菌YIT2004株的抗生素敏感性及对万古霉素耐药机制

目的 研究嗜酸乳杆菌YIT2004株的抗生素敏感性及其耐药机制。方法 最低抑菌浓度法检测嗜酸乳杆菌YIT2004株对抗生素的敏感性;提取YIT2004株基因组,用特异性引物对耐药基因进行PCR扩增。结果 嗜酸乳杆菌YIT2004株对青霉素、氨苄西林、亚胺培南、庆大霉素、红霉素和克林霉素敏感,对万古霉素耐药;YIT2004株基因组中不存在vanA、vanB耐药基因,但存在高度相似的aad、ddl万古霉素耐药基因。该耐药为固有耐药,不具备传递性。结论 嗜酸乳杆菌YIT2004株对青霉素、氨苄西林、亚胺培南、庆大霉素、红霉素和克林霉素敏感,对万古霉素固有耐药且其耐药性不可传递。嗜酸乳杆菌YIT2004株的使用具有安全性。     

平菇浸汁促进嗜酸乳杆菌生长的研究

对平菇浸汁可促进嗜酸乳杆菌的生长进行了初步研究。结果表明,平菇浸汁对嗜酸乳杆菌在还原脱脂乳中的生长具有明显的促进作用,添加5％～10％的平菇浸汁,可大大缩短嗜酸乳杆菌生长的世代时间,提高其产酸速率;在37℃下1Oh的培养,其中活菌数的含量较对照组大大提高,可达108/mL。     

乳酸、乙酸及pH对嗜酸乳杆菌和阴道加德纳菌的生长及交互作用影响

目的 探讨乳酸、乙酸及pH值变化对嗜酸乳杆菌和阴道加德纳菌的生长及交互作用影响,为探究细菌性阴道病患者治疗失败的可能原因提供依据。方法 （1）两菌经不同浓度乳酸、乙酸作用后,检测其细菌浓度变化。（2）两菌经不同pH的SBHIG肉汤单独及混合培养,检测其细菌浓度变化并涂片观察生长情况。结果 乳酸、乙酸浓度1.0%~5.0%时,均可抑制两菌的生长。0.1%乳酸对阴道加德纳菌生长的抑制能力较弱,但可促进嗜酸乳杆菌的生长。肉汤培养基在pH 3.5时,几乎只有嗜酸乳杆菌能生长;pH 8.5时,生长的细菌中阴道加德纳菌占绝大多数;pH 5.5和7.0时,两菌虽然共同生长,但嗜酸乳杆菌生长明显受抑制。结论 嗜酸乳杆菌与阴道加德纳菌存在交互作用,但受细菌浓度、乳酸和乙酸浓度及pH的影响。细菌性阴道病患者需多疗程疗治疗或治疗失败可能与乳杆菌累积浓度未能达到抑制阴道加德纳菌生长的要求有关。     

复方嗜酸乳杆菌片联合乳果糖对糖尿病便秘患者脑肠肽水平的影响

目的 探讨复方嗜酸乳杆菌片联合乳果糖对糖尿病便秘患者脑肠肽水平的影响.方法 选择2018年1月-2019年8月在我院内科门诊治疗的糖尿病便秘患者92例,随机分为观察组和对照组各46例.两组均予建立良好生活习惯、饮食调整、适当运动、排便锻炼及药物控制血糖等基础治疗.对照组在此基础上加乳果糖口服液15 mL/次,2次/d,...     

Protective Effects of a Culture Supernatant of Lactobacillus acidophilus and Antioxidants on Ileal Ulcer Formation in Rats Treated with a Nonsteroidal Antiinflammatory Drug

Ileal ulcers and thiobarbituric acid (TBA)-reactive substances in the ileal mucosa were induced in rats treated with a nonsteroidal antiinflammatory drug, 5-bromo-2-(4-fluorophenyl)-3-(4-methylsulfonylphenyl)thiophene (BFMeT), at a dose of 1,000 mg/kg administered with tap water as drinking water. However, the formation of ileal ulcers and TBA-reactive substances in the ileal mucosa was repressed by giving the animals a culture supernatant of Lactobacillus acidophilus as drinking water. We measured the antioxidative activity of the culture supernatant and found that the supernatant inhibited the formation of t-butyl hydroperoxide-induced TBA-reactive substances in erythrocyte membrane ghosts. Therefore, the effects of various known antioxidative compounds on the ileal ulcer formation induced by BFMeT were investigated. While α-tocopherol, t-butyl-1,4-hydroxyanisole and allopurinol did not repress ulcer formation after BFMeT treatment, ascorbic acid, dimethyl sulfoxide, glutathione and β-carotene significantly inhibited formation. Among these compounds, ascorbic acid was the most effective. Accumulation of TBA-reactive substances in the ileal mucosa after BFMeT treatment also decreased significantly in rats treated with ascorbic acid. In addition, the percentage of Gram-negative rods in the ileal contents of rats treated with BFMeT and tap water was dramatically increased, but it was not increased in rats treated with BFMeT and these antioxidants. A positive correlation between the percentage of Gram-negative rods and the number of ileal ulcers was also observed. These results suggest that lipid peroxidation mediated by oxygen radicals plays an important role in the induction of ileal ulcers by BFMeT in rats, and that lipopolysaccharide-activated neutrophils probably produce highly reactive hypochlorous acid and hydrogen peroxide, which are inactivated by ascorbic acid and glutathione, respectively.     

多菌种混合发酵无醇饮料的研究

以大麦芽、大麦和大米为主料,优质红茶为辅料,依据微生物生理代谢与生态的基本原理,选择了三个菌种混合发酵,开发了一种新型发酵无醇饮料。采用的三个菌种是：酵母菌（Ｓａｃｃｈａｒｏｍｙｃｅｓｃｅｒｉｖｉｓｉａｅ）,嗜酸乳酸菌（Ｌａｃｔｏｂａｃｉｌｌｕｓａｃｉｄｏｐｈｉｌｕｓ）,弱氧化醋酸单胞菌（Ａｃｅｔｏｍｏｎａｓｓｕｂｏｘｙｄａｎｓ）。将上述菌种按一定比例（１：１：２）接种,接种总量为发酵基质的１０％,控制发酵温度２０－２５℃,发酵时间５天,即可制成风格独特、口味纯正的新型发酵无醇饮料（含醇量＜１％）。     

复方嗜酸乳杆菌片联合三联方案根除幽门螺杆菌的临床研究

目的探讨复方嗜酸乳杆菌片联合三联方案根除幽门螺杆菌(Helicobacter pylori,H.pylori)的疗效及不良反应。方法将143例H.pylori检测阳性的患者随机分为A1组(48例)、A2组(46例)和B组(49例)。B组给予三联方案(埃索美拉唑、阿莫西林、克拉霉素)根除H.pylori治疗,疗程10d。A1组、A2组分别在上述三联方案的基础上同时加用10d、20d的复方嗜酸乳杆菌片。治疗过程中观察并记录上述三组的不良反应发生情况,停药4周后查13 C呼气试验判别H.pylori根除是否成功。结果共133例患者完成治疗和随访,A1组、A2组、B组根除率按方案(PP)分析分别为65.9%、69.8%、63.0%,按意向性(ITT)分析分别为60.4%、65.2%、59.2%,无论按方案分析还是意向性分析三组根除率差异均无统计学意义(P0.05)。纳入三组的共143例患者均完成不良反应的随访,A1组、A2组、B组不良反应发生率分别为10.4%、8.7%、30.6%,三组相比差异有统计学意义(P0.05),其中A1组、A2组分别与B组相比差异有统计学意义(P0.05),A1组与A2组相比差异无统计学意义(P0.05)。结论三联方案加用10d、20d的复方嗜酸乳杆菌片未能提高H.pylori根除率,但可降低不良反应发生率。