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1.
The viability of six different strains of probiotic vaginal Lactobacillus was examined in two different cryoprotective media, during refrigerated versus frozen storage, and using two traditional types of stock cultures for starting the biomass production. Freezing at -20 degrees C and -70 degrees C had much less adverse effect on viability than did storage at 7 degrees C, and the reduction in viability was greater at -20 degrees C than at -70 degrees C. The strains showed variation in the extent of the viability losses during both types of storage. Milk-yeast extract (MYE) was shown to be the more suitable protective medium to maintain viability of the strains during the storage. The vaginal Lactobacillus strains are most stable in MYE at -70 degrees C with only a small decrease of the viability observed under these conditions. The viable cell counts of Lactobacillus paracasei CRL 1251 and CRL 1289, L. crispatus CRL 1266 and L. salivarius CRL 1328 remained around 1 x 10(8) CFU/mL after 24 months of storage at -70 degrees C, or up to 18 months for L. acidophilus CRL 1259. 相似文献
2.
Bifidobacterium lactis V9(B.lactis V9)是一株具有良好益生特性且遗传稳定的益生茵,工业化生产环境中气体组成关系着益生菌活菌数量,进而影响其益生功效.[目的]研究不同气体环境对B.lactis V9生长及代谢的影响.[方法]在固体MRS培养基、液体MRS培养基及巴氏杀菌脱脂乳接种B.lactis V9,于不同的气体环境中培养.[结果]在固体MRS培养基上,B.lactis V9在混合气体(N2∶H2∶CO2=80∶10∶10)环境中菌落形成较氮气环境(N2∶99.99%)多,在空气环境(N2∶O2≈79∶21)中菌落形成极少.B.lactis V9在MRS液体中培养24 h,混合气体环境下其活菌数(9.11±0.11 log CFU/mL)显著高于空气环境下的活菌数(8.04±0.10 log CFU/mL) (P<0.01),在混合气体环境下B.lactis V9代谢生成的乙酸和乳酸量分别为12.79±0.86 mmol/L和11.99±0.73 mmol/L,显著高于在空气环境中生成量0.65±0.07 mmol/L和2.75±0.57 mmol/L (P<0.01),乙酸/乳酸比值分别为1.06∶1和0.24∶1.B.lactis V9在巴氏杀菌脱脂乳中发酵18h,混合气体环境下pH值(4.48±0.07)显著低于空气环境下的pH值(5.03±0.12) (P<0.01),混合气体环境下其活菌数(9.02±0.15 log CFU/mL)显著高于空气环境下的活菌数(8.53±0.08 log CFU/mL) (P<0.01).混合气体和空气环境下发酵脱脂乳产生的乙酸和乳酸量分别为60.52±2.30 mmol/L、5.17±1.02 mmol/L和16.86±0.34 mmol/L、5.92±0.81 mmol/L,乙酸/乳酸的值分别为11.71∶1和2.85∶1.[结论]在N2∶H2∶CO2=80∶10∶10混合气体环境下有利于B.lactis V9在液体MRS和脱脂乳中生长,其活菌数可以增加0.5-1个数量级.这一研究结果也可为B.lactis V9益生菌发酵乳的生产和产品中B.lactis V9活菌培养计数提供指导. 相似文献
3.
Pirkka V. Kirjavainen Hani S. El-Nezami Seppo J. Salminen Jorma T. Ahokas Paul F.A. Wright 《FEMS immunology and medical microbiology》1999,26(2):131-135
Four common Lactobacillus strains were screened for their effects on proliferation of mouse splenic lymphocytes. Mice received perorally 10(9) viable bacteria kg(-1) body weight for 7 days. Lactobacillus acidophilus treatment enhanced ex vivo basal proliferation (by 43%) and B-cell response at suboptimal and optimal concentrations of lipopolysaccharide (LPS) (by 27-28%). Conversely, Lactobacillus casei, Lactobacillus gasseri and Lactobacillus rhamnosus inhibited both basal proliferation (by 14-51%) and mitogen-stimulated lymphoproliferation, particularly at supra-optimal concentrations of concanavalin A (by 43-68%) and LPS (by 23-62%). Therefore, these Lactobacillus strains demonstrate strain-specific effects on B- and T-cells and may also alter the splenocyte sensitivity to the cytotoxic effects of mitogens. 相似文献
4.
Biofilm formation in an ice cream plant 总被引:1,自引:0,他引:1
The sites of biofilm formation in an ice cream plant were investigated by sampling both the production line and the environment. Experiments were carried out twice within a 20-day period. First, stainless steel coupons were fixed to surfaces adjacent to food contact surfaces, the floor drains and the doormat. They were taken for the analysis of biofilm at three different production stages. Then, biofilm forming bacteria were␣enumerated and also presence of Listeria monocytogenes was monitored. Biofilm forming isolates were selected on the basis of colony morphology and Gram’s reaction; Gram negative cocci and rod, Gram positive cocci and spore forming isolates were identified. Most of the biofilm formations were seen on the conveyor belt of a packaging machine 8 h after the beginning of the production, 6.5 × 103 cfu cm−2. Most of the Gram negative bacteria identified belong to Enterobacteriaceae family such as Proteus, Enterobacter, Citrobacter, Shigella, Escherichia, Edwardsiella. The other Gram negative microflora included Aeromonas, Plesiomonas, Moraxella, Pseudomonas or Alcaligenes spp. were also isolated. Gram positive microflora of the ice cream plant included Staphyloccus, Bacillus, Listeria and lactic acid bacteria such as Streptococcus, Leuconostoc or Pediococcus spp. The results from this study highlighted the problems of spread of pathogens like Listeria and Shigella and spoilage bacteria. In the development of cleaning and disinfection procedures in ice cream plants, an awareness of these biofilm-forming bacteria is essential for the ice cream plants. 相似文献
5.
《Saudi Journal of Biological Sciences》2016,23(4):503-506
Aspartame is an artificial sweetener used as an alternate for sugar in several foods and beverages. The study reports that consumption of aspartame containing product could lead to cancer. However, the effect of aspartame on apoptosis process in cancer is not yet understood clearly. HeLa cells were exposed to different concentrations (0.01–0.05 mg/ml) of aspartame for 48 h. Cytotoxicity of aspartame on cancer cells was determined by SRB assay. The result indicates no significant changes on cell viability. Aspartame suppresses apoptosis process in cancer cells by down-regulation of mRNA expression of tumor suppressor gene p53, and pro-apoptotic gene bax. It up-regulates anti-apoptotic gene bcl-2 mRNA expression. In addition, Ki 67 and PCNA mRNA, and protein expressions were determined. Taking all these together, we conclude that aspartame may be a potent substance to slow-down the apoptosis process in HeLa cells. Further works are ongoing to understand the biochemical and molecular mechanism of aspartame in cancer cells. 相似文献
6.
We have compared the gas phase thermochemical properties of aspartame (artificial sweetener) and α- and β-glucose. These parameters include metal ion affinities with Li+-, Na+-, K+-, Mg+2-, Ca+2-, Fe+2-, Zn+2-ions, and chloride ion affinity by using DFT calculations. For example, for aspartame, the affinity values for the above described metal ions are, respectively, 86.5, 63.2, 44.2, 255.4, 178.4, 235.4, and 300.4, and for β-glucose are 65.2, 47.3 32.9, 212.9, 140.2, 190.1, and 250.0 kcal mol−1, respectively. The study shows differences between the intrinsic chemistry of aspartame and glucose. 相似文献
7.
The objective of this article is to review genotoxicologic and carcinogenic profile of the artificial sweetener aspartame. Aspartame is a synthetic dipeptide, nearly 180–200 times sweeter than sucrose. It is the most widely used artificial sweetener especially in carbonated and powdered soft drinks, beverages, drugs and hygiene products. There is a discussion ongoing for many years whether aspartame posses genotoxic and carcinogenic risk for humans. This question led to many studies to specify the adverse effects of aspartame. Therefore, we aimed to review the oldest to latest works published in major indices to gather information within this article. With respect to published data, genotoxicity and carcinogenicity of aspartame is still confusing. So, consumers should be aware of the potential side effects of aspartame before they consume it. 相似文献
8.
V. Aparna Sudhakaran Harsh Panwar Ritu Chauhan Raj Kumar Duary Rahul Kumar Rathore Virender Kumar Batish Sunita Grover 《Genes & nutrition》2013,8(6):637-648
The anti-inflammatory potential of eight indigenous probiotic Lactobacillus isolates was evaluated in vitro in terms of modulating the expression of tumor necrosis factor-alpha (TNF-α) and interleukin-6 (IL-6) in human acute monocytic leukemia (THP-1) cells under inflammatory conditions. Amongst these, Lactobacillus plantarum Lp91 was the most potent anti-inflammatory strain as it evoked a significant (P < 0.001) down-regulation of TNF-α by −1.45-fold relative to the control in THP-1 cells. However, in terms of IL-6 expression, all the strains could up-regulate its expression considerably at different levels. Hence, based on in vitro expression of TNF-α, Lp91 was selected for in vivo study in lipopolysaccharide (LPS)-induced mouse model to look at the expression of TNF-α, IL-6, monocyte chemotactic protein-1 (MCP-1), vascular cell adhesion molecule-1 (VCAM-1), intercellular adhesion molecule (ICAM-1) and E-selectin in mouse aorta. In LPS challenged (2 h) mice group fed with Lp91 for 10 days, TNF-α, IL-6, MCP-1, VCAM-1, ICAM-1 and E-selectin expressions were significantly down-regulated by 3.10-, 10.02-, 4.22-, −3.14-, 2.28- and 5.71-fold relative to control conditions. In conclusion, Lp91 could serve as a candidate probiotic strain to explore it as a possible biotherapeutic anti-inflammatory agent against inflammatory diseases including cardiovascular disease.
Electronic supplementary material
The online version of this article (doi:10.1007/s12263-013-0347-5) contains supplementary material, which is available to authorized users. 相似文献9.
Probiotic use of lactobacilli in the human female urogenital tract 总被引:13,自引:0,他引:13
Jacqueline A. McGroarty 《FEMS immunology and medical microbiology》1993,6(4):251-264
10.
子痫前期(preeclampsia,PE)是妊娠期高血压疾病(hypertensive disorders of pregnancy,HDP)之一,严重损害母婴健康,影响3%~5%的妊娠。随高通量测序技术的发展和普及,肠道微生物与人类健康和疾病的关系逐渐清晰。PE患者肠道微生物群结构变化与疾病的发生发展密切相关,失调的肠道菌群很可能会成为PE早期诊断的生物标志物或干预的靶点。本文总结了以测序技术为基础获得的正常妊娠女性和PE患者肠道微生物分布规律数据,并提出益生菌调理建议,以期为PE的科学预测、精准干预提供理论支持。 相似文献
11.
12.
K.A. Ryan T. Jayaraman P. Daly C. Canchaya S. Curran F. Fang E.M. Quigley P.W. O’Toole 《Letters in applied microbiology》2008,47(4):269-274
Aims: Recent evidence suggests that the human gastric microbiota is much more diverse than previously thought. The aim of this study was to assess the potential for isolating lactobacilli from the human stomach. Methods and Results: Lactobacilli were selectively cultured from gastric biopsies from 12 patients undergoing routine endoscopy. Lactobacilli were present in four of 12 biopsies. We isolated, in total 10 different strains representing five species (Lactobacillus gasseri, L. fermentum, L. vaginalis, L. reuteri and L. salivarius). The 10 isolates varied greatly in their ability to inhibit the growth of two Gram‐positive bacteria and two Gram‐negative bacteria. Furthermore, the acid and bile resistance profiles of the 10 isolates spanned a wide range. Conclusions: Five different Lactobacillus species were cultured from human gastric biopsies for the first time. Significance and Impact of the Study: Diverse Lactobacillus species are more prevalent in the human stomach than previously recognized, representing an untapped source of bacteria with beneficial probiotic and/or biotechnological properties. 相似文献
13.
目的探讨微生态调节剂双歧杆菌三联活菌对慢性肝衰竭患者肠道菌群的影响。方法根据治疗方法不同将46例慢性肝衰竭患者随机分为治疗组和对照组各23例,两组均给予慢性肝衰竭常规治疗,治疗组在上述基础上给予双歧杆菌三联活菌胶囊,210mg/粒,每次2粒,2次/d,疗程2周。观察治疗前后两组患者的肠道菌群菌落计数变化及血清总胆红素(TBiL)、凝血酶原时间(PT)变化。结果两组患者在实验前肠道菌群、TBiL、PT比较差异均无统计学意义(P〉0.05)。治疗2周后,对照组患者治疗前后肠道菌群无明显变化(P〉0.05),TBiL、PT有所下降但不显著,治疗组患者的肠球菌、双歧杆菌、乳杆菌以及酵母样真菌的菌落数均较治疗前明显增加,TBiL、PT较前明显好转(P〈0.05)。结论口服双歧杆菌三联活菌制剂可以促进慢性肝衰竭患者肠道正常菌群的恢复及改善肝功能。 相似文献
14.
艾滋病(AIDS)是一种具有极大危害性的传染性疾病。AIDS发病和死亡都呈现明显上升趋势,传播模式发生变化,疫情由高危人群向一般人群扩散。因此,AIDS/HIV已成为中国的一个严重的公共卫生问题,政府对此极为重视。目前AIDS的治疗药物主要包括NNRTIs、NRTIs、PIs、FIs、CRIs和INIs这6大类,因长期使用这些药物的副作用以及此病合并的并发症特性,探讨其发病机制及寻找新的治疗思路,一直是此病研究领域中的热点。随着肠道微生态学研究领域的发展,应用人体无害的益生菌治疗HIV感染相关腹泻逐渐受到全球关注,就此作一综述。 相似文献
15.
Lactobacilli are believed to be beneficial for the human hosts and are currently being evaluated as potentially probiotic bacteria. In this study, Lactobacillus strains were isolated from infant faeces and were examined in vitro for potential probiotic properties. Faecal specimens from 63 healthy, full-term infants were collected at 4, 30 and 90 days after delivery. Seventy-four Lactobacillus strains were isolated and one or more different phenotypes from each infant (n = 44) were selected for further testing. The bacterial isolates were identified mainly as L. gasseri, L. crispatus, Lactobacillus paracasei, L. salivarius, L. fermentum after amplification and sequencing of 16s rRNA gene. The strains were examined for acid and bile tolerance, adhesion to Caco-2 cells, antibiotic susceptibility and antimicrobial activity against selected enteric pathogens. The great majority of the isolated lactobacilli were susceptible to ampicillin, amoxicillin/clavulanic acid, tetracycline, erythromycin, cephalothin, chloramphenicol and rifampicin. Resistance to vancomycin or bacitracin was detected to 34% of the strains. Twenty strains out of forty-four exhibited significant tolerance to bile salts. Those strains were subsequently tested for resistance to low pH conditions (pH 2 and 3). Interestingly, 85% (17 strains) of the tested lactobacilli remained unaffected at pH 3 after 3 h of incubation, 6 strains were found resistant at pH 2 after 1.5 h and only 2 strains found resistant after 3 h of incubation. Two of the strains were able to adhere to Caco-2 cells. In conclusion, two isolates fulfilled the in vitro probiotic criteria and are good candidates for further in vivo evaluation. 相似文献
16.
目的观察微生态制剂(思连康)辅助治疗活动期溃疡性结肠炎(UC)的疗效和安全性,并进一步探讨微生态制剂对肠黏膜局部细胞因子的影响。方法活动期UC患者86例,随机分为2组,对照组(40例)口服美沙拉嗪,同时用琥珀酸氢化考的松及庆大霉素、蒙脱石散保留灌肠,重度患者加静脉用激素。治疗组(46例)在上述治疗基础上,口服思连康1.5 g,每天3次。治疗6个月后评价2组疗效,主要症状和结肠镜变化情况,免疫组化法检测患者肠黏膜局部细胞因子IL-10、IL-6和IL-18的变化。结果治疗后2组临床表现均有明显好转,且治疗组优于对照组,2组比较差异有统计学意义(P<0.05)。2组治疗后结肠镜表现均有明显改善,治疗组优于对照组;疾病活动指数(DAI)降低(P<0.05),降低幅度治疗组优于对照组(P<0.05)。所有患者均未见明显的不良反应。免疫组化结果显示治疗后肠黏膜细胞因子IL-10的水平升高,治疗组优于对照组,IL-6和IL-18均有降低,IL-6下降治疗组优于对照组,而IL-18的降低2组间差异无统计学意义。结论微生态制剂口服辅助治疗UC疗效明显,并能降低UC的复发,且无不良反应。其机制可能与上调局部肠黏膜抗炎性细胞因子,下调炎性细胞因子有关。 相似文献
17.
目的 探讨益生菌制剂对2型糖尿病患者的疗效及其对肠道菌群的影响。 方法 选取医院收治的92例2型糖尿病患者随机分为对照组和研究组,各46例。对照组给予基础治疗,研究组给予基础治疗联合益生菌制剂。对比治疗前后两组患者临床症状评分和糖代谢指标水平变化,肠道菌群的组成及多样性变化,治疗效果和药物不良反应。 结果 治疗后两组患者Chao1指数和Shannon指数均升高(均P0.05)。 结论 益生菌制剂能够控制2型糖尿病患者的临床症状,改善糖代谢,增加肠道菌群的多样性,调节肠道菌群属水平相对丰度,还可增强疗效且安全。 相似文献
18.
The human body is colonized by a vast array of bacteria whose diversity is largely affected by predation of bacteriophages. Here, we discussed the impact of bacteriophages on the composition of human intestinal microbiota as well as on the survival and thus efficacy of probiotic bacteria in the human gut. 相似文献
19.
益生菌的功能机制越来越受学者们的关注,尤其是分子水平上的益生菌-宿主相互作用功能机制的研究越来越受关注.本文就益生菌-宿主相互作用机制以及研究方法进行综述. 相似文献
20.
天女木兰花粉形态特征及其生活力 总被引:7,自引:0,他引:7
对天女木兰(Magnolia sieboldii)花粉的采集时期、形态以及培养的温度和培养基进行了研究,并探讨贮存温度和时间对花粉生活力的影响。结果表明,扫描电镜观察到的花粉形状和萌发孔与其他已报道的木兰科植物相同,但大小和花粉外壁的纹理不同。在花瓣刚刚展开的初花期采集的花粉生活力最高。25℃下最适于花粉的萌发;花粉在含10%蔗糖+0.1%硼酸的培养基上培养14h的萌发率最高,0.01%~0.05%的氯化钙对花粉的萌发影响不显著,0.1%的氯化钙对花粉的萌发有抑制作用。随着贮存时间的延长,花粉萌发率不断降低。不同贮存温度下花粉萌发率的降低速度依次为-10℃〈4℃〈25℃,-10%下贮藏5d的花粉萌发率降低了48.8%,10d后萌发率降低为0。 相似文献