巴马长寿老人源乳酸杆菌的筛选及其益生特性

为获得巴马长寿老人肠道乳杆菌并研究其益生特性,采用改良MRS+Ca CO3固体培养基与改良MRS+X-gal固体培养基从10位广西巴马百岁老人粪便中筛选出19株乳杆菌,再通过生理生化实验、糖发酵实验、模拟胃肠转运实验、疏水性实验和自凝集实验,筛选出消化道逆环境耐受性强和粘附力好的菌株3株(GU-L3、GU-P132和GU-G23),进一步对三株菌进行了16Sr DNA序列鉴定,结果发现GU-L3为干酪乳杆菌(Lactobacillus casei);GU-P132为发酵乳杆菌(Lactobacillus fermentum);GU-G23为格氏乳杆菌(Lactobacillus gasseri)。三个菌株经模拟胃肠液转运实验后,存活率皆达到107 CFU/m L以上,自凝集率分别为12.43±0.03%、78.88±0.01%和35.92±0.02%,疏水率分别为6.38±0.02%、81.77±0.02%和10.58±0.05%,粘附性也高于其他菌株。经与国内外有关报道相比,综合认为这三株来自巴马老人肠道的乳酸杆菌益生特性明显,具有较好的开发潜力。

Screening of Intestinal Lactobacillus from Bama Centenarians and Their Probiotic Characteristics

In order to study the probiotic characteristics of Lactobacillus obtained from Bama centenarians, improved MRS+CaCO3 and MRS+X-gal solid culture media were used to isolate and culture the Lactobacillus from the feces of 10 Guangxi centenarians. After culturing, 19 strains of Lactobacillus were selected. Three of these strains (GU-L3, GU-P132, and GU-G23) with high tolerance to adverse gastrointestinal environments and good adhesiveness were obtained through physiological and biochemical experiments, sugar fermentation experiments, simulated gastrointestinal transit experiments, and auto-aggregation and hydrophobicity screening. Sequencing of 16S rDNA revealed that GU-L3 was Lactobacillus casei, GU-P132 was Lactobacillus fermentum, and GU-G23 was Lactobacillus gasseri. After the simulated gastrointestinal transit experiment, the survival rates of the L. casei, L. fermentum, and L. gasseri were found to be above 107 cfu/mL, while the auto-aggregation rates were 12.43±0.03%, 78.88±0.01%, and 35.92±0.02%, respectively, and the hydrophobicity rates were 6.38±0.02%, 81.77±0.02%, and 10.58±0.05%, respectively. The adhesiveness of these strains was already known to be higher than that of the other strains. Compared with the reports of related domestic and international probiotic strains, the GU-L3, GU-P132, and GU-G22 intestinal Lactobacillus strains from Bama centenarians had better probiotic characteristics and development potential.