光合细菌益生特性的实验研究
发布时间：2018-12-06 12:24
【摘要】：背景: 人类整个胃肠道(gastrointestinal tract,GIT)栖居着大量微生物,这些微生物构成了GIT的生物屏障。但GIT随时经受各种内源性和外源性的氧化应激,导致胃肠黏膜的氧化损伤。人类已就微生物应对氧化应激开展了少量研究。据报道一些乳酸杆菌具有抗氧化特性,能减少摄入食物过程中活性氧自由基(reactive oxygen species,ROS)的富集。一些乳酸菌还能降解超氧阴离子自由基和H_2O_2。据报道类球红细菌体内外有抗氧化作用,但作用部位不具体,作用机理不确切。尚未见其它种类光合细菌(photosynthetic bacteria,PSB)抗氧化作用的报道,也未见具有抗氧化作用的PSB对氧化损伤胃肠黏膜保护作用的研究报道。 当前PSB作为益生菌株已在国外的保健食品中应用,但尚未列入国内允许用于保健食品的菌种名单内,可见PSB作为益生菌株已有一定应用基础,但尚缺乏益生特性的系统资料。 目的: 本课题对8株PSB作为益生菌的安全性、功效性、工艺特性等益生特性进行初步研究,并对其进行系统鉴定,同时建立大鼠胃肠黏膜的急性水浸氧化应激模型来探讨PSB在宿主体内对氧化损伤胃肠黏膜的保护作用,为开发PSB保健品、药品提供益生特性资料和功效开发方向,以促进PSB在保健品、药品中的应用。 实验方法: (一)本课题通过表型特征、培养特征、生理生化特征和菌株的16S rDNA序列分析对8株PSB菌株进行了系统鉴定。(二)观察8株PSB菌株体外对8种抗生素药敏纸片的敏感性;对菌株2c(10~(10)CFU/mL)的安全性进行体内实验,包括急性毒性实验,检测血液中内毒素含量,用细菌培养方法观察摄入菌株2c后是否造成细菌易位,用扫描电镜和透射电镜观察菌株2c对肠黏膜和细胞结构有无不良影响,用试剂盒检测反映肝肾功能的血液生理生化指标了解菌株2c是否对肝肾功能有不良影响。(三)通过以下方法对PSB菌株的功效性进行了实验:(1)研究8株PSB菌株体外对酸和胆盐的耐受、在模拟胃液和小肠液中的存活率、体外对4种肠道常见致病菌的抑制作用和菌株体外对HT-29细胞的黏附作用,以及用Van Niel富集培养基富集培养大鼠摄入PSB期间以及停止摄入PSB后一周之内粪便中的PSB,以预测菌株在宿主体内存活和持续情况。(2)检测8
[Abstract]:Background: human gastrointestinal tract (gastrointestinal tract,GIT) inhabit a large number of microorganisms, which constitute the biological barrier of GIT. However, GIT is subjected to various endogenous and exogenous oxidative stress at any time, leading to oxidative injury of gastrointestinal mucosa. Little research has been done on the response of microorganisms to oxidative stress. Some Lactobacilli are reported to have antioxidant properties that reduce the concentration of reactive oxygen free radical (reactive oxygen species,ROS) during food intake. Some lactic acid bacteria can also degrade superoxide anion free radicals and H _ 2O _ 2s _ 2. It is reported that globular red bacteria have antioxidation effect in vivo and in vitro, but the action site is not specific and the mechanism is not exact. There are no reports on the antioxidant effects of other photosynthetic bacteria (photosynthetic bacteria,PSB) or the protective effects of PSB on oxidative injury of gastrointestinal mucosa. Currently, PSB as a probiotic strain has been used in health food abroad, but it has not been included in the list of strains allowed for health food in China. It can be seen that PSB as a probiotic strain has a certain application foundation, but there is still no systematic data on probiotics. Objective: to study the probiotic characteristics of 8 strains of PSB as probiotics, including their safety, efficacy and technological characteristics, and to identify them systematically. At the same time, an acute water-immersion oxidative stress model of rat gastrointestinal mucosa was established to study the protective effect of PSB on oxidative injury of gastrointestinal mucosa in the host, and to provide the information of probiotic characteristics and the development direction of efficacy for the development of PSB health products and drugs. To promote the application of PSB in health products and medicines. Methods: (1) eight strains of PSB were systematically identified by phenotypic, culture, physiological and biochemical characteristics and 16s rDNA sequence analysis. (2) to observe the sensitivity of 8 PSB strains to 8 antibiotic sensitive tablets in vitro; The safety of strain 2c (10 ~ (10) CFU/mL) was tested in vivo, including acute toxicity test, endotoxin content in blood, bacterial culture method was used to observe whether bacterial translocation was caused by strain 2c ingestion. The negative effects of strain 2c on intestinal mucosa and cell structure were observed by scanning electron microscope (SEM) and transmission electron microscope (TEM). The blood physiological and biochemical indexes reflecting liver and kidney function were detected by kit to determine whether strain 2c had adverse effect on liver and kidney function. (3) the efficacy of PSB strains was tested by the following methods: (1) the tolerance of 8 PSB strains to acid and bile salt in vitro and the survival rate in simulated gastric juice and intestinal fluid were studied. Inhibition of four common intestinal pathogens in vitro and adhesion of the strains to HT-29 cells in vitro, and PSB, in feces of rats enriched with Van Niel enrichment medium during uptake of PSB and within one week after cessation of PSB intake To predict the survival and persistence of the strain in the host. (2) Detection 8
【学位授予单位】：第三军医大学
【学位级别】：博士
【学位授予年份】：2005
【分类号】：R37
本文编号：2366021
[Abstract]:Background: human gastrointestinal tract (gastrointestinal tract,GIT) inhabit a large number of microorganisms, which constitute the biological barrier of GIT. However, GIT is subjected to various endogenous and exogenous oxidative stress at any time, leading to oxidative injury of gastrointestinal mucosa. Little research has been done on the response of microorganisms to oxidative stress. Some Lactobacilli are reported to have antioxidant properties that reduce the concentration of reactive oxygen free radical (reactive oxygen species,ROS) during food intake. Some lactic acid bacteria can also degrade superoxide anion free radicals and H _ 2O _ 2s _ 2. It is reported that globular red bacteria have antioxidation effect in vivo and in vitro, but the action site is not specific and the mechanism is not exact. There are no reports on the antioxidant effects of other photosynthetic bacteria (photosynthetic bacteria,PSB) or the protective effects of PSB on oxidative injury of gastrointestinal mucosa. Currently, PSB as a probiotic strain has been used in health food abroad, but it has not been included in the list of strains allowed for health food in China. It can be seen that PSB as a probiotic strain has a certain application foundation, but there is still no systematic data on probiotics. Objective: to study the probiotic characteristics of 8 strains of PSB as probiotics, including their safety, efficacy and technological characteristics, and to identify them systematically. At the same time, an acute water-immersion oxidative stress model of rat gastrointestinal mucosa was established to study the protective effect of PSB on oxidative injury of gastrointestinal mucosa in the host, and to provide the information of probiotic characteristics and the development direction of efficacy for the development of PSB health products and drugs. To promote the application of PSB in health products and medicines. Methods: (1) eight strains of PSB were systematically identified by phenotypic, culture, physiological and biochemical characteristics and 16s rDNA sequence analysis. (2) to observe the sensitivity of 8 PSB strains to 8 antibiotic sensitive tablets in vitro; The safety of strain 2c (10 ~ (10) CFU/mL) was tested in vivo, including acute toxicity test, endotoxin content in blood, bacterial culture method was used to observe whether bacterial translocation was caused by strain 2c ingestion. The negative effects of strain 2c on intestinal mucosa and cell structure were observed by scanning electron microscope (SEM) and transmission electron microscope (TEM). The blood physiological and biochemical indexes reflecting liver and kidney function were detected by kit to determine whether strain 2c had adverse effect on liver and kidney function. (3) the efficacy of PSB strains was tested by the following methods: (1) the tolerance of 8 PSB strains to acid and bile salt in vitro and the survival rate in simulated gastric juice and intestinal fluid were studied. Inhibition of four common intestinal pathogens in vitro and adhesion of the strains to HT-29 cells in vitro, and PSB, in feces of rats enriched with Van Niel enrichment medium during uptake of PSB and within one week after cessation of PSB intake To predict the survival and persistence of the strain in the host. (2) Detection 8
【学位授予单位】：第三军医大学
【学位级别】：博士
【学位授予年份】：2005
【分类号】：R37
【引证文献】
相关期刊论文 前1条
1 许乐乐;王园园;刘春娥;李永芹;Kevin David Penkava;庄如豪;李泽宇;王学超;;光合细菌功能型胡萝卜汁饮料的研制[J];食品科技;2013年02期
，本文编号：2366021
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