乳酸菌胞外多糖的研究

介绍了乳酸菌胞外多糖研究，主要包括乳酸菌胞外多糖的种类和合成、遗传调控、生理功能、分离纯化和结构分析、构效关系及应用。     

肠膜明串珠菌胞外多糖的研究进展及其在饲料业中的应用前景

综述了肠膜明串珠菌胞外多糖的存在形式、组成成分、酶促合成过程、生成影响因素及提高产量的技术,介绍了肠膜明串珠菌胞外多糖的功能及用途,探讨了专供发酵饲料使用的肠膜明串珠菌的菌株选育问题、饲用肠膜明串珠菌微生态制剂的生产问题及低聚糖益生元饲料添加剂开发问题。     

一种通过肠膜明串珠菌发酵的花样奶布丁的研制

目前市售布丁主要是调制型奶布丁,是根据口味差异调制所需配料,加入明胶等凝固而成,虽有一些"半发酵型"的布丁产品,主要是以酸奶为原料进行调制而成,但其凝固成型过程主要依赖于添加的各种稳定剂,无法兼顾到美味、营养和健康.为此,本文研究了一种以脱脂乳和番茄汁为介质、基于肠膜明串珠菌发酵的花样奶布丁,其保留了牛乳中的各种营养物...     

产胞外多糖乳酸菌筛选及胞外多糖提取方法

从实验室保存及市售泡菜和发酵乳中分离的乳酸菌中进行筛选,通过黏度和EPS产量的测定,筛选出一株高产EPS的乳酸菌,为实验室保存菌株干酪乳杆菌,黏度为354.04mPa·s,产量为731.58mg/L。EPS提取过程中,比较了Sevag法和三氯乙酸法两种除蛋白方法,8%三氯乙酸除蛋白的方法效果最好。     

明串珠菌应用研究进展

明串珠菌是一类进行异型发酵的革兰氏阳性兼性厌氧乳酸菌,是众多传统发酵制品中的优势菌群,可应用于食品、化工、医疗等领域。本文从目前国内外研究现状出发,概述明串珠菌的分离筛选及特性,介绍了有关明串珠菌基因组学、蛋白质组学、代谢组学的研究进展,进而对其应用情况进行概括,旨在为今后明串珠菌能够更有效地应用于工业化生产和生活提供理论依据。     

乳酸菌胞外多糖

本文综述了目前关于乳酸菌胞外多糖(EPS)的结构、化学组成、影响乳酸菌EPS产生的因素等方面的研究现状及乳酸菌胞外多糖的应用。     

乳酸菌胞外多糖生物合成条件的研究

利用乳酸菌生长的液体培养基MRS作为米酒乳杆菌BXR-5-3胞外多糖（EPS）产生的基本培养基,并在该基础上对培养基进行调整,主要对碳源、氮源、培养基的初始pH值、发酵温度和发酵时间对EPS合成的影响进行了探讨．研究发现,该菌生物合成EPS的适宜条件为：葡萄糖和乳糖是该菌株合成EPS的合适的碳源,添加量分别为15g／L,培养基的初始pH值7．0,发酵温度35℃,发酵时间26h。     

胞外多糖对酸奶稳定性的研究

乳酸菌代谢生长过程会产生胞外多糖,胞外多糖对酸奶的物化特性具有重要的影响。采用硫酸-苯酚法测定不同发酵菌种胞外多糖的产量,对不同菌种发酵产品口感状态、黏度、持水性、耐热性进行比较分析。试验结果表明,胞外多糖能改善产品口感状态,提高产品黏度,提高产品持水性,增强产品耐热性,为以后酸奶的开发与应用提供一定的理论依据。     

乳与乳制品中明串珠菌的分离鉴定

从内蒙古通辽市科左后旗和扎鲁特旗牧民家庭乳样中分离到61株乳酸菌,并进行乳酸菌的分离鉴定。结果显示,其中有肠膜明串珠菌葡聚糖亚种2株,假肠膜明串珠菌1株,明串珠菌分离率为4．9％。     

乳酸菌发酵产生胞外多糖的研究进展

本文概述了乳酸菌胞外多糖（EPS）的生物合成途径,EPS产量的影响因素及对其结构性能的研究。     

1株具有免疫增强功能的乳酸菌筛选及其免疫效果评价

为筛选出具有较强免疫功能的益生菌用于临床研究,对分离自健康鸡粪便样品中的20株乳酸菌进行耐酸、耐胆盐、体外抑菌、黏附、胞外多糖含量测定试验以及小鼠免疫功能检测,并结合上述试验结果进行综合性评价.结果:筛选出20号菌株为目的菌株,耐酸、耐胆盐试验表明,该菌株在pH=2时的存活率为72.7％,在胆盐浓度为1.0％的环境中存...     

Characterization and application of lactic acid bacteria for tropical silage preparation

Strains TH 14, TH 21 and TH 64 were isolated from tropical silages, namely corn stover, sugar cane top and rice straw, respectively, prepared in Thailand. These strains were selected by low pH growth range and high lactic acid‐producing ability, similar to some commercial inoculants. Based on the analysis of 16S ribosomal RNA gene sequence and DNA‐DNA relatedness, strain TH 14 was identified as Lactobacillus casei, and strains TH 21 and TH 64 were identified as L. plantarum. Strains TH 14, TH 21, TH 64 and two commercial inoculants, CH (L. plantarum) and SN (L. rhamnosus), were used as additives to fresh and wilted purple Guinea and sorghum silages prepared using a small‐scale fermentation method. The number of epiphytic lactic acid bacteria (LAB) in the forages before ensilage was relatively low but the numbers of coliform and aerobic bacteria were higher. Sorghum silages at 30 days of fermentation were all well preserved with low pH (3.56) and high lactic acid production (72.86 g/kg dry matter). Purple Guinea silage inoculated with LAB exhibited reduced count levels of aerobic and coliform bacteria, lower pH, butyric acid and ammonia nitrogen and increased lactic acid concentration, compared with the control. Strain TH 14 more effectively improved lactic acid production compared with inoculants and other strains. © 2016 Japanese Society of Animal Science     

活性多糖在发酵乳中的应用研究进展

分子生物学技术已证实,活性多糖作为一种天然高分子聚合物具有多种生理生化活性功能,其中活性多糖络合水的能力、高黏度、抗氧化及抗衰老等特性奠定了其应用于食品领域的基础,将活性多糖与食品相结合生产功能性食品成为当下研究的热点.发酵乳具有良好的风味和益生性能,但是也存在诸如货架期较短、凝乳品质较差、益生性能表现一般等问题,如何...     

不同浓度赤霉酸对饲料添加菌生长的影响

为研究不同浓度的赤霉酸对饲料添加菌生长的影响,用2种不同浓度的赤霉酸溶液单独添加饲料乳酸菌（A4+A7）和纤维素分解菌（Nf+Y6）进行培养52 h,其中每4 h作一个单位测定出OD_{600 nm}值并绘制生长曲线,分析不同浓度的赤霉酸对饲料添加菌生长的影响。结果表明,赤霉酸浓度为10 mg/L时,各组OD_{600 nm}值分别为0.64、0.70、0.84、0.78、0.72,其中试验组2的OD_{600 nm}值与对照组和其他试验组相比有明显增高,总活菌数高达11.6×10⁸ CFU/mL,比对照组（1.63×10⁸ CFU/mL）高7倍以上;当赤霉酸浓度增加到20 mg/L时,各组OD_{600 nm}值分别为0.64、0.60、0.59、0.59、0.63,其中各试验组的OD_{600 nm}值与对照组相比无明显差异（P>0.05）,试验组活菌数（1.60×10⁸ CFU/mL）与对照组相比（1.63×10⁸ CFU/mL）无明显差异（P>0.05）。通过试验数据和生长曲线得知赤霉酸浓度在10 mg/L时能促进乳酸菌和纤维素分解菌的生长繁殖;赤霉酸浓度为20 mg/L时乳酸菌和纤维素分解菌的生长速度明显下降。综上提示,适当添加赤霉酸对饲料添加菌生长有明显的促进作用,赤霉酸浓度过高则饲料添加菌的生长量降低。     

Microbiota of 'airag', 'tarag' and other kinds of fermented dairy products from nomad in Mongolia

The traditional fermented dairy products were collected from three nomadic families in Donto‐Govi prefecture in Mongolia (central Mongolia), and those microbiota were analyzed. These samples consist three of ‘airag’, two of ‘tarag’, two of ‘isgelen tarag’ and ‘qoormog’, and some cheeses. In airag, Lactobacillus (L.) helveticus, L. kefiri, and Saccharomyces (S.) dairensis were common, and L. paracasei, L. plantarum, L. farciminis, S. cerevisiae, Issachenkia (I.) orientalis, Kluyveromyces (K.) wickerhamii were also found. In tarag, isgelen tarag and qoormog, L. helveticus, L. kefiri, L. fermentum, L. paracasei and L. acetotolerance were found. L. delbrueckii subsp. bulgaricus was also found in one tarag and one qoormog samples. Randomly amplified polymorphic DNA (RAPD) analysis showed that there were diversity in each L. helveticus family and products, and there were common strains found in airag and tarag in the same family.     

Effects of oral supplementation of probiotic strains of Lactobacillus rhamnosus and Enterococcus faecium on diarrhoea events of foals in their first weeks of life

Foal first diarrhoea is one of the most prominent problems in the early life of horses. Probiotics might have the potency to prevent or at least diminish neonatal diarrhoea. We hypothesised that the treatment of foals with probiotic strains of Lactobacillus rhamnosus and Enterococcus faecium starting early after birth and then daily over 2 weeks would prevent or mitigate foal heat diarrhoea. The influence of this probiotic treatment on diarrhoea incidence and growth and health performance of young foals was investigated. Thirty‐four foals were randomly allocated to two groups. From day 1 to 14 of life, the foals received either placebo (PG, n = 16) or the probiotic treatment (TG, n = 18). Clinical examination was performed, and the faeces consistency score (FCS, 1–5; with diarrhoea defined by ≤3) was recorded once per day in weeks 1 and 2 and once weekly in weeks 3–8 of life (WL). The body height was measured at birth and after two and eight WL. Diarrhoea occurred in the 1st WL in 19% and 61% of PG and TG foals respectively. In the 1st WL, diarrhoea lasted 0.3 ± 0.8 and 1.6 ± 1.4 days in PG and TG foals respectively. In the 2nd WL, diarrhoea occurred in 94% and 84% of PG and TG foals, respectively, and lasted for 3.0 ± 1.5 and 3.7 ± 1.6 days respectively. At least two periods of diarrhoea developed in 33% and 65% of PG and TG foals respectively. The TG foals grew slightly slower than the PG foals. The results indicated that the probiotic treatment of neonatal foals as performed in this study was not suitable to reduce diarrhoea within the first two WL, because contrary to the hypothesis, the TG foals suffered more frequently and for longer periods from diarrhoea than the PG foals.     

Effect of microbial inoculants on the fermentation characteristics,nutritive value,and in vitro digestibility of various forages

This study was aimed to examine the characteristics of three isolated lactic acid bacteria (LAB) strains (HG24, M1, and TG1), and to evaluate their effects on fermentation characteristics, nutritive value, and in vitro digestibility in a variety of substrates. The experiments were conducted with Italian ryegrass (Lolium multiflorum Lam.), tall fescue (Festuca arundinacea Schred.), and oat (Avena sativa L.) in laboratory silo (1 L) for ensiling 30 days. All the treated silages had significantly (p < 0.05) higher in vitro dry matter digestibility (IVDMD), and lower undesirable microorganism populations compared with controls. In Italian ryegrass and oat silages, all the inoculants improved the fermentation quality, evidenced by distinctly (p < 0.05) higher LA contents and ratios of LA to acetic acid, and lower pH, butyric acid and ammonia nitrogen contents. Strains HG24 and commercial inoculant G (Lactobacillus plantarum MTD‐1) performed better than strains M1 and TG1, indicated by obviously (p < 0.05) higher LA contents, LAB numbers, and IVDMD. In tall fescue silage, all the isolated LAB strains (HG24, M1 and TG1) markedly (p < 0.05) increased IVDMD compared with strain G. Strain HG24 is recommended as a good LAB inoculant for ensiling in various forages.     

乳酸菌发酵扶正解毒散复合制剂的制备及其在肉鸡上的应用研究

本研究旨在制备一种乳酸菌发酵的扶正解毒散复合制剂,并探索其对肉鸡生长性能和免疫器官发育的影响。首先,利用单因子试验法将不同比例的黄芪、板蓝根、淫羊藿及复合中药提取液添加至乳酸菌的培养基中,测定中药对乳酸菌生长的影响;其次,利用正交试验对复合药液培养基进行优化,确定最佳的培养基配方;最后,选取1日龄健康AA肉仔鸡450只,随机分为3组,每组3个重复:对照组(抗生素)、试验Ⅰ组(发酵制剂)、试验Ⅱ组(未发酵制剂),分别在试验的第21、42天测定肉鸡的生长及免疫器官指标。试验结果显示,黄芪、板蓝根、淫羊藿及复合药液组的最高活菌数与对照组相比分别提高了261.64%、505.48%、156.16%、564.38%。通过正交试验得到复合发酵液最适生产培养基配方:复合药液100 mL、红糖2.0 g、蛋白胨0.3 g、豆粕2.0 g,发酵液活菌数为7.13×10⁹ CFU/mL。肉鸡生长试验结果显示,1~42日龄阶段,Ⅰ、Ⅱ组的平均日增重分别比对照组提高了17.84%和8.22% (P<0.05),料肉比分别比对照组降低了10.88%和4.66% (P<0.05),平均日采食量明显高于对照组 (P<0.05);21、42日龄时,Ⅰ、Ⅱ组脾指数分别比对照组提高了11.04%和13.58% (P<0.05)、7.79%和7.41% (P<0.05),法氏囊指数分别比对照组提高了31.30%和26.23% (P<0.05)、15.65%和11.48% (P<0.05)。以上试验结果表明中药提取液能促进乳酸菌的增殖,复合发酵液能够提高肉鸡的生长性能并促进免疫器官的发育。     

低聚糖对雏鸡大肠粪便NH3-N含量及肠道菌群的影响

试验选取1日龄罗曼蛋公雏250只，随机分为5组，试验组饲料或饮水中分别添加海藻糖(500mg／kg)、海藻胶(600mg／kg)、大豆寡糖(500mg／kg)、圆葱寡糖(500mg/d)。结果表明，四种低聚糖均可促进肠道乳酸菌及双歧杆菌的生长繁殖，对魏氏梭菌的生长呈现抑制作用。海藻糖、海藻胶对降低大肠粪便NH3—N含量效果不显著(P＞0．05)，而大豆寡糖效果显著(P＜0．05)，圆葱寡糖效果极显著(P＜0.01)。