Growth inhibition of Listeria monocytogenes by a bacteriocin of Pediococcus acidilactici M during fermentation of kimchi

Four lactic acid bacteria known to produce bacteriocins were evaluated for the inhibitory effect against Listeria monocytogenes strain Scott A. Lactococcus lactis subsp. lactis biovar diacetylactis 26-2 was the least antilisterial, whereas Pediococcus acidilactici M resulted in the largest zone of inhibition on an agar medium. Leuconostoc paramesenteroides OX and Lactobacillus sake Lb 706 were intermediate. Aqueous solutions of crude bacteriocin powders derived from supernatant fluids of L. sake Lb 706 and P. acidilactici M. cultures inhibited the growth of Lactobacillus plantarum UGA8 in MRS agar. The addition of 10 mg of crude bacteriocin powder from L. sake to 150 g of kimchi fermented at 14 ± 1°C for 16 days had no effect on the growth of L. monocytogenes. The same amount of crude bacteriocin derived from P. acidilactici, however, had an initial lethal effect on L. monocytogenes and controlled growth of the pathogen throughout the 16-day fermentation. The successful application of bacteriocins to control the growth of L. monocytogenes in lightly fermented foods such as kimchi would appear to be achievable.     

Increased antioxidative and nitric oxide scavenging activity of ginseng marc fermented by Pediococcus acidilactici KCCM11614P

Food Science and Biotechnology - This study aimed to improve the antioxidant and nitric oxide scavenging activities of ginseng marc fermented by Pediococcus acidilactici, thereby creating a...     

Effect of a bacteriocin produced by Pediococcus acidilactici against Listeria monocytogenes and Clostridium perfringens on Spanish raw meat

The inhibitory effect of a bacteriocin, produced by Pediococcus acidilactici, against Listeria monocytogenes and Clostridium perfringens on Spanish raw meat surface, was evaluated by in situ assays. Samples were incubated with the bacteriocin and then with a culture of the pathogenic bacteria. The treatment with 500, 1000 or 5000 bacteriocin units/ml (BU/ml) reduced the counts of L. monocytogenes after storage at 15°C during 72h by 1, 2 or 3 log cycles and with 1000 or 5000 BU/ml after storage at 4°C during 21 days by 2.5 or 3.5 log cycles, respectively, compared to the control. With C. perfringens a bacteriostatic effect could be observed.     

乳酸片球菌发酵液中主要有机酸及其抑菌性研究

为研究乳酸片球菌发酵产生的有机酸与其抑菌活性之间的相关性,采用spot-on-lawn法及琼脂扩散法研究其抑菌活性,利用HPLC分析发酵液主要有机酸组分。结果表明:乳酸片球菌以葡萄糖作为发酵碳源时发酵能力最强,且主要抑菌物质为有机酸;乳酸、乙酸与总酸含量与抑菌活性存在正相关性(P<0.05)。乳酸片球菌发酵液有机酸组分与抑菌活性的研究为开发新型生物防腐剂的潜在菌株的筛选提供依据。     

乳酸足球菌精氨酸代谢与瓜氨酸积累

酿造酱油中氨基甲酸乙酯的主要前体物质瓜氨酸由乳酸足球菌通过精氨酸代谢产生。为了研究酱油中瓜氨酸的积累机制,以分离自酱油成曲的乳酸足球菌Pediococcus acidilactici BBE1120为研究对象,考察不同培养条件(碳源、盐浓度、氨基酸)对其积累瓜氨酸的影响。结果表明,高盐环境是导致乳酸足球菌积累瓜氨酸的关键因素,碳源的种类及浓度对瓜氨酸的积累也有一定影响,培养基中精氨酸、瓜氨酸、鸟氨酸含量对瓜氨酸的积累影响不大。该研究结果对阐明酱油发酵过程中氨基甲酸乙酯前体物质的积累机制具有重要意义。     

乳酸片球菌细菌素的分离纯化及理化性质

将乳酸片球菌接种于MRS培养基,37℃静置培养17h产生细菌素。根据细菌素在pH6.0时与菌体的吸附力最强,pH2.0时吸附力最弱,通过调节pH和离心来分离纯化细菌素,得率为22.80%,比活为4.526×104AU/mg;细菌素的理化性质实验表明,细菌素经120℃处理20min仍保留70.08%的活性;在pH2～9范围内20℃处理3h抑菌活性稳定,当pH≥9时活性逐渐降低;经胃蛋白酶、胰蛋白酶、木瓜蛋白酶和蛋白酶K处理后均无抑菌活性。实验表明,该细菌素耐热、耐酸、耐碱,对蛋白酶敏感,具有开发为安全、天然的食品防腐剂的良好前景。     

乳酸片球菌抑菌物质细菌素的分离纯化

将乳酸片球菌接种于MRS培养基,37℃静置培养17h后产生抑菌物质细菌素.用三步法从培养液中分离纯化细菌素:首先根据细菌素在pH6.0时与菌体的吸附力最强,pH2.0时吸附力最弱,通过调节pH和离心来收集细菌素,然后经过SP Sepharose Fast Flow阳离子交换柱层析和Sephadex G-50凝胶层析进行纯化,最后细菌素的得率为0.19%,比活为5.17×104AU/mg,纯化了34.54倍.得到的细菌素样品通过Tricine-SDS-PAGE电泳出现清晰条带,大小约为4600D.     

从酸白菜中分离出一株产细菌素的乳酸片球菌

本试验从酸白菜中分离出一株有抑制单核细胞增多症李氏杆菌作用的菌株,经鉴定为乳酸片球菌,还对植物乳杆菌、金黄色葡萄球菌、蜡样芽胞杆菌等革兰氏阳性细菌有抗菌作用。该抗菌物质对蛋白水解酶敏感、对过氧化氢酶不敏感、耐热、在较宽的pH范围内保持活性。在排除是有机酸和过氧化氢后,初步认为该菌产生的抗菌物质为抗菌肽,即细菌素。     

Pediococcus acidilactici as a potential probiotic to be used in food industry

The objective of this study was to compare the results obtained between a commercial probiotic bacterium and a strain of Pediococcus acidilactici isolated from a food matrix. Besides the characterisation of the isolates, the main focus of this work was to evaluate their ability to survive through simulated gastrointestinal tract passage as well as the effect of the spray drying process to be used as concentrated cultures in the food industry. Both lactic acid bacteria produced any of the virulence determinants investigated; they exhibited no significant antibiotic resistances and <1 log unit reduction in viable counts was obtained after exposure to simulated gastrointestinal tract conditions. Concentrated cultures of P. acidilactici HA‐6111‐2 in 10% (w/v) of reconstituted skim milk were obtained by spray drying and, after 60 days of storage at 4 °C, <1 log unit reduction in viable count was recorded. In conclusion, from these preliminary characterisation tests and its extended viability in the dried form, this P. acidilactici strain should be considered as a potentially useful probiotic.     

乳酸片球菌液态法发酵猪肉的工艺研究

研究了乳酸片球菌液态法发酵猪肉的生产工艺.对影响发酵的因素 --盐浓度、亚硝酸钠浓度、接种量、发酵时间和发酵温度等进行优化实验研究,通过正交试验,得到盐浓度2.5%、亚硝酸钠浓度 0.012%、接种量 3.5%、发酵时间 21h、发酵温度 30℃的优化发酵工艺条件.优化发酵条件下所得产品,微生物及NaNO 2含量均达到标准,具有良好的发酵肉风味,结果令人满意.     

乙酰辅酶A羧化酶对乳酸片球菌耐酸性能的影响

通过对来源于山西老陈醋固态酿造过程中的乳酸菌分离株的耐醋酸性能分析,筛选得到了醋酸耐受性较优的乳酸片球菌（Pediococcus acidilactici）AAF3-3,该菌株对其他种类的酸压力（乳酸和盐酸）也表现出一定的耐受性。利用定量实时聚合酶链反应（qRT-PCR）对该菌株中乙酰辅酶A羧化酶基因（acc）的转录水平进行分析发现,其在醋酸、乳酸和盐酸下的转录水平分别是无压力条件下的4.32、2.02和1.13倍,均出现了明显上调。进一步构建该基因的过表达菌株并进行耐酸性能分析。结果表明,与对照菌株相比,acc过表达菌株在3种酸压力下的生长性能和存活性能均有所提高,其中,3%（V/V）醋酸条件下培养24 h时过表达菌株的相对活菌数是对照菌株的24倍。这表明乙酰辅酶A羧化酶在乳酸片球菌AAF3-3耐受不同种类的酸压力中发挥着重要作用。     

一株强化发酵甜瓣子的乳酸片球菌特性及应用效果评价

甜瓣子是以蚕豆制曲后加盐水发酵而成的,是郫县豆瓣风味形成的关键阶段。筛选适用于强化甜瓣子发酵的专用乳酸菌,以期应用于强化甜瓣子发酵。以甜瓣子为原料筛选生长速度快、产酸能力强的高效乳酸菌,研究其生长特性。利用筛选得到的高效乳酸菌制备菌剂并用于强化甜瓣子发酵,分析甜瓣子品质。该研究筛选得到1株乳酸片球菌ND1,37℃培养6 h、OD610达1. 375,培养24 h发酵液中乳酸含量达到1. 296 g/100 g。ND1在4～50℃条件生长良好,高温更利于其生长,在37～45℃生长速度最快;能耐受10%的盐,在盐含量(质量分数)为0%～8%的条件生长良好;在pH 3. 5～6生长速度快。利用菌株ND1发酵得到的乳酸菌剂活菌数可达1. 07×10¹²CFU/g,利用该菌剂发酵甜瓣子,可有效提高甜瓣子中有机酸(尤其是乙酸、苹果酸、乳酸)含量,强化甜瓣子风味。该研究筛选的乳酸片球菌ND1具有良好的温度、酸度、盐度适应性,能改善甜瓣子中有机酸含量,有望被用作强化甜瓣子发酵增香的乳酸菌,改善郫县豆瓣品质。     

添加乳酸片球菌AS185的益生菌Ricotta干酪品质评价

将一株益生性乳酸片球菌（Pediococcus acidilactici）AS185添加到Ricotta干酪中,通过理化指标、质构特性、乳酸菌活菌数、挥发性成分分析等评价AS185对干酪品质的影响。结果表明,经4 ℃冷藏21 d后,添加乳酸片球菌AS185的益生菌乳清干酪的脂肪、蛋白质和水分质量分数分别为17.60%、27.47%和49.95%,pH值为4.75,均与未添加益生菌的对照干酪无显著差异。贮藏21 d,乳酸菌活菌数为7.45 log CFU/g,符合益生菌产品要求;益生菌乳清干酪的硬度、粘聚性、胶着度和咀嚼度分为723.85 N、0.97 mm、699.58和699.61 mJ,均高于对照干酪,其质地更为结实,更具有咀嚼感。在挥发性成分的种类和含量方面,益生菌乳清干酪共检测出15类成分,其中酸类、醇类、酮类的相对含量较高,分别为38.56%、24.64%、13.76%,均高于对照组;在外观色泽、滋气味和组织状方面,益生菌干酪与对照干酪无显著差异（p>0.05）,但整体可接受性方面优于对照组,说明益生菌乳酸片球菌AS185的添加对干酪风味的形成有积极作用。乳酸片球菌AS185具有适合Ricotta乳清干酪加工的技术特性,是一株有应用前景的益生菌菌株。     

In vitro evaluation of Pediococcus acidilactici NCDC 252 for its probiotic attributes

In vitro probiotic attributes of Pediococcus acidilactici, viz. tolerance to acidity and bile salt, phenol resistance, lactic acid production, antioxidant activity, cell surface hydrophobicity, lysozyme resistance and the presence of β‐galactosidase, proteolytic, lipase and peptidoglycan hydrolase activities, were studied. The strain was found to be rich in different proteolytic activities, β‐galactosidase and antioxidant activities, and produced lactic acid. The studies conducted support that P. acidilactici national collection of dairy cultures (NCDC) 252 is a potential probiotic for humans with all the essential basic probiotic properties. This testing is useful to gain insight into this strain and its mechanism of action. All these attributes add to its therapeutic importance and industrial significance.     

Partial characterisation of an anti-listeria substance produced by Pediococcus acidilactici P9

To improve the microbiological security of food products, 285 lactic acid bacteria were isolated from koumiss and pickles, and their antimicrobial properties were characterised. Among the strains, Pediococcus acidilactici P9, a strain isolated from a local pickled vegetable, produced an antagonistic substance that inhibited Listeria monocytogenes and Shigella. The substance was heat (121 °C for 20 min) and pH (2.0–10.0) stable, but sensitive to proteolytic enzymes. The production of bacteriocins started at the exponential phase and reached its maximum at the stationary phase, indicating that it was growth related. P. acidilactici P9 also showed an ability to protect HT-29 from invasion by L. monocytogenes and the inhibition rate reached 35.89%. P. acidilactici P9 showed a potential for application in food products as a biopreservative.     

乳酸片球菌AS185调节高脂高糖饮食诱导的代谢综合征

目的:研究乳酸片球菌(Pediococcus acidilactici)AS185对代谢综合征小鼠的调节作用,并探讨其作用机制.方法:高脂高糖饮食诱导小鼠代谢综合征造模(6周),灌胃乳酸片球菌AS185,每天1次,连续8周,通过测量体质量、血糖浓度、血脂和血清炎症因子水平并进行Western blot检测,评价乳酸片球...     

Effect of bacteriocin‐producing Pediococcus acidilactici K10 on beer fermentation

Beer is generally considered to be a beverage that has high microbiological stability. However, some undesirable lactic acid bacteria (LAB) can grow in beer and consequently spoil this beverage. In this study, bacteriocin‐producing Pediococcus acidilactici K10 was used as a means of bio‐acidifying the mash and reducing the spoilage LAB content of the beer. The K10 strain had antimicrobial activity against two beer spoilage LAB strains in wort and did not grow in a beer environment. The K10 strain was inoculated before the mashing step. The effect of K10 as a starter culture was investigated and compared with a control. As a result, filtration time was shortened by 17 min, alcohol content was increased by 137%, foam stability was increased by 156%, bitterness was increased by two bitterness units and there was a significant difference (p < 0.05) in aromatic and sour odour. The feasibility of using bacteriocin‐producing LAB strain in beer brewing is envisaged. Copyright © 2016 The Institute of Brewing & Distilling     

乳酸片球菌R-4细菌素PA-1原核表达及其理化特性

为实现原核表达产出细菌素并检测其理化特性,作者将乳酸片球菌 R-4细菌素pedA基因进行扩增回收,与pMD19-T载体连接后转入E.coli DH5α感受态细胞进行克隆。提取克隆后的pedA基因与表达载体pET-32a（+）连接,形成重组质粒pET-32a-pedA并转入E.coli BL21(DE3)感受态细胞,经异丙基硫代半乳糖苷诱导,乳酸片球菌R-4细菌素PA-1在大肠杆菌细胞进行表达。表达蛋白质经Ni-NTA柱纯化后,以金黄色葡萄球菌为指示菌检测其理化特性。结果表明,在E.coli BL21(DE3)细胞中成功表达相对分子质量为26 000的乳酸片球菌R-4细菌素PA-1并完成纯化。纯化后的乳酸片球菌R-4细菌素PA-1在40~121 ℃作用20 min、在pH 2~12、紫外线照射0~10 h、过氧化氢酶作用2 h后,其抑菌范围分别为14.7~15.6 mm、14.0~16.5 mm、15.1~15.8 mm和14.9 mm,而分别经胃蛋白酶和胰蛋白酶作用2 h均失去抑菌作用。这表明乳酸片球菌R-4细菌素PA-1对高温、强酸强碱、紫外线和过氧化氢酶均具有较好的稳定性,而胃蛋白酶和胰蛋白酶会使其失活。     

Pediocin PA-1 production during repeated-cycle batch culture of immobilized Pediococcus acidilactici UL5 cells

Pediocin PA-1 production by Pediococcus acidilactici UL5 cells immobilized in kappa-carrageenan/locust bean gum gel beads was studied during repeated-cycle batch (RCB) culture with pH control in Man Rogosa and Sharpe (MRS) broth supplemented with 1% glucose and whey permeate (SWP) medium. The pediocin PA-1 production by free P. acidilactici cells pH-controlled batch culture has reached 2048 and 4096 AU ml(-1) after 11 and 12 h of incubation, with volumetric productivities of 187 and 342 AU ml(-1) h(-1) in SWP and MRS media, respectively. In RCB culture, immobilized cells reached a maximum concentration of 7.3+/-0.2 x 10(10) and 4.3+/-0.9 x 10(10) cfu g(-1) of beads in MRS and SWP media, respectively. The maximum pediocin PA-1 activity obtained during RCB fermentation was 4096 AU ml(-1); it was attained after only 0.75 and 2 h of incubation in MRS and SWP media, respectively. The corresponding volumetric productivities were 5461 and 2048 AU ml(-1) h(-1). Pediocin PA-1 production in the RCB culture was highly stable over 12 fermentation cycles carried out over 3 d in SWP media.     

Production of 3-phenyllactic acid and 4-hydroxyphenyllactic acid by Pediococcus acidilactici DSM 20284 fermentation

It was reported that 3-phenyllactic acid (PLA) and 4-hydroxyphenyllactic acid (HPLA) could be produced by Pediococcus acidilactici DSM 20284. PLA and HPLA concentrations were 0.65 and 0.25 mM when P. acidilactici DSM 20284 was grown in MRS broth for 36 h. In comparison with P. acidilactici DSM 20284 fermentation using MRS medium alone, PLA and HPLA production could be significantly promoted by the supplement of the corresponding amino acid (phenylalanine and tyrosine) and ketoacid (phenylpyruvic acid and 4-hydroxyphenylpyruvic acid) precursors in MRS broth, but inhibited by the supplement of the non-corresponding precursors. Promotion and inhibitory effects were both strengthened when supplement amounts increased. Ketoacids precursors showed more promotion effect on the corresponding 2-hydroxy acids production than amino acid precursors; however, amino acid precursors showed more inhibitory effect on non-corresponding 2-hydroxy acids production than ketoacids precursors.