扬州稀甜酱中乳酸菌的分离鉴定及抑菌活性初探

以扬州稀甜酱为研究对象,采用经典乳酸菌筛选法从样品中分离、纯化乳酸菌,采用形态学观察、生理生化试验和16S rRNA序列分析对乳酸菌进行鉴定,并采用牛津杯法对发酵滤液的抑菌活性进行研究。结果表明,从扬州稀甜酱中共分离、纯化出33株乳酸菌,其中15株菌株被鉴定为屎肠球菌（Enterococcus faecium）,12株菌株被鉴定为乳酸片球菌（Pediococcus acidilactici）,4株菌株被鉴定为类肠膜魏斯氏菌（Weissella paramesenteroides）,2株菌株被鉴定为酸鱼乳杆菌（Lactobacillus acidipiscis）,屎肠球菌和乳酸片球菌为扬州稀甜酱中的优势乳酸菌。乳酸片球菌TJ17和TJ31发酵滤液对金黄色葡萄球菌（Staphylococcus aureus）、单核细胞增生李斯特氏菌（Listeria monocytogenes）和大肠埃希氏菌（Escherichia coli）均有明显的抑制作用,且乳酸片球菌TJ31抑菌效果较好。     

新疆传统乳品中乳酸菌的抗氧化能力

实验用菌为从新疆传统乳制品酸奶和干酪中分离出的7株乳酸菌,分别是乳酸片球菌(Pediococcus acidilactici)1株、植物乳杆菌(Lactobacillus plantarum)3株、耐久肠球菌(Enterococcus durans)1株、魏斯氏菌(Weissella cibaria)1株和面包乳杆菌(Lactobacillus panis)1株。对其清除DPPH自由基、超氧阴离子自由基、羟自由基、还原能力以及亚铁离子螯合能力进行了研究。结果表明:7株乳酸菌具有不同的抗氧化能力,其中植物乳杆菌亚铁离子螯合能力最强,乳酸片球菌超氧阴离子自由基清除能力相对较高,魏斯氏菌的DPPH自由基清除能力较强,面包乳杆菌的羟自由基清除能力和还原能力最强。     

水牛乳中可培养乳酸菌多样性分析

采用传统分离培养方法,从三品杂交生水牛奶混合样品中,分离出105株乳酸菌,通过形态、生理生化、API细菌鉴定系统及16S rDNA基因序列分析方法对各菌株属种进行鉴定。16S rRNA序列分析结果显示,105株菌共分为5个属8个种,呈现较为丰富的乳酸菌多样性,具体数量分布为乳酸乳球菌21株,植物乳杆菌19株,格氏乳球菌17株,乳明串珠菌13株,食窦魏斯氏菌11株,肠膜明串珠菌8株,类肠膜魏斯氏菌6株,嗜热链球菌5株,糊精乳杆菌5株。由此可知,水牛乳中可培养乳酸菌优势菌群的主次关系为：乳酸乳球菌（Lactococcus lactis）＞植物乳杆菌（Lactobacillus plantaru）＞格氏乳球菌（Lactococcus garvieae）＞乳明串珠菌（Leuconostoc lactis）＞食窦魏斯氏菌（Weissella cibaria）,此为后续开发水牛乳中优势乳酸菌资源提供了良好的理论基础。     

新疆传统酸奶中乳酸菌的筛选鉴定及菌相分析

酸奶是新疆各少数民族经常食用的一种乳制品。从新疆采集的22个酸奶样品中共分离出56株乳酸菌,通过形态特征观察、生理生化实验、糖发酵实验等传统鉴定方法,结合16S r DNA序列分析对其进行鉴定。结果表明,新疆传统酸奶中菌相构成为德氏乳杆菌(Lactobacillus.delbrueckii subsp.)46株(占总分离株的82%);发酵乳杆菌(Lactobacillus.fermentum)2株(4%);瑞士乳杆菌(Lactobacillus.helveticus)2株(4%);嗜酸乳杆菌(Lactobacillus acidophilus)1株(2%);鸡乳杆菌(Lactobacillus.gallinarum)2株(4%);屎肠球菌(Enterococcus faecalis)1株(2%);耐久肠球菌(Enterococcus canis)2株(4%)。说明新疆传统酸奶中德氏乳杆菌为优势菌。     

臭鳜鱼中优良乳酸菌的分离筛选与鉴定

从臭鳜鱼中分离纯化得到50株疑似乳酸菌,按照肉制品发酵剂筛选标准,获得了4株优良乳酸菌L4、L12、L20和L36,其均具良好的耐盐性、发酵性和生长特性。经传统生理生化鉴定及16S rDNA序列分析,优良乳酸菌L4、L12、L20和L36分别为屎肠球菌(Enterococcus faecium)、弯曲乳杆菌(Lactobacillus curvatus)、坚强肠球菌(Enterococcus durans)、干酪乳杆菌(Lactobacillus casei)。     

广西地区青年人肠道乳酸菌的分离及其发酵酸奶品质的评价

采用传统的可培养方法对广西青年人肠道乳酸菌进行了分离与纯化,通过16S rRNA序列分析对菌株进行了鉴定,并将筛选菌株作为酸奶发酵剂应用。结果表明,分离到的23株乳酸菌中被鉴定为发酵乳杆菌（Lactobacillus fermentum）11株,唾液乳杆菌（Lactobacillus salivarius）6株,格氏乳杆菌（Lactobacillus gasseri）2株,副干酪乳杆菌（Lactobacillus paracasei）1株,融合魏斯氏菌（Weissella confuse）2株和口乳杆菌（Lactobacillus oris）1株。筛选乳酸菌制作的酸奶之间芳香类物质差异并不显著（P＞0.05）,而酸奶样品间酸味、后味A和丰度差异较大。进一步分析表明,副干酪乳杆菌HBUAS54287、唾液乳杆菌HBUAS54223与HBUAS54248、格氏乳杆菌HBUAS54233、发酵乳杆菌HBUAS54238与HBUAS54318乳酸产生能力较强,可进一步筛选用于酸奶复合发酵剂的开发。     

新疆伊犁地区乳品中发酵菌种的筛选及产酸性能研究

通过传统分离方法从新疆伊犁州乳品中初步分离纯化出71株乳酸菌,其中具有明显产酸凝乳特性的乳酸菌8株,经生理生化鉴定以及16S rRNA序列比对分析,确定8株乳酸菌的种属分别为德氏乳杆菌保加利亚亚种(Lactobacillus delbrueckii subsp.bulgaricus)、开菲尔乳杆菌(Lactobacillus kefiranofaciens)、发酵乳杆菌(Lactobacillus fermentum)、植物乳杆菌(Lactobacillus plantarum)、乳酸明串球菌(Leuconostoc lactis)和粪肠球菌(Enterococcus faecalis)。对8株乳酸菌的生长性能、产酸性能、后酸化性能、感官特性等多个指标进行分析得出,德氏乳杆菌BSTS6-1、BSTS6-3、BSTS6-4生长速度快、产酸速率高,发酵乳风味纯正、组织形态良好且菌株后酸化能力弱,符合酸乳发酵菌种的基本特征。     

新疆酸马奶中乳酸菌的多态性分析及发酵性能研究

以新疆牧民传统家庭自制酸马奶样品为研究对象,考察乳酸菌的多态性及筛选优良性状的乳酸菌菌株。通过16S r RNA基因序列分析和生理生化试验等方法对分离出的菌株进行鉴定,并进行发酵性能测试。结果表明,本实验共分离出19株菌株,包括乳酸乳球菌乳酸亚种(Lactococcus lactis subsp.lactis)(8株)、粪肠球菌(Enterococcus faecalis)(2株)、屎肠球菌(Enterococcus faecium)(2株)、嗜热链球菌(Streptococcus thermophilus)(1株)、干酪乳杆菌(Lactobacillus casei)(3株)、植物乳杆菌(Lactobacillus plantarum)(2株)和徳氏乳杆菌乳酸亚种(Lactobacillus delbrueckii subsp.Lactis)(1株)。其中,干酪乳杆菌JDB1.1505是一株产酸和产黏性能都比较突出的乳酸菌,发酵脱脂乳的滴定酸度达到了130.1°T,黏度为1420.1m Pa·s,具有良好的乳品发酵应用潜能。     

南宁地区米酒曲源乳酸菌在糯米汁中氨基酸和有机酸代谢特征研究

该研究采用纯培养技术对广西省南宁地区米酒曲中乳酸菌多样性进行了解析,旨在揭示其分离株在糯米汁中产氨基酸和有机酸的特征。结果表明,11个样品共分离出20株乳酸菌,分别被鉴定为戊糖片球菌（Pediococcus pentosaceus）、融合魏斯氏菌（Weissella confuse）、类肠膜魏斯氏菌（Weissella paramesenteroides）、屎肠球菌（Enterococcus faecium）、台湾乳球菌（Lactococcus taiwanensis）、植物乳杆菌（Lactobacillus plantarum）和戊糖乳杆菌（Lactobacillus pentosus）,其中戊糖片球菌（P. pentosaceus）占分离株的35%,为南宁地区米酒曲中的优势乳酸菌。选取除屎肠球菌（E. faecium）外的16株乳酸菌分离株进行糯米汁纯种发酵,结果发现所有菌株均不产氨基酸,乳酸为糯米汁中主要有机酸。主成分分析（PCA）结果表明,融合魏斯氏菌（W. confuse）HBUAS53367产有机酸的能力较强,可用于后续进一步研究。     

水牛乳中高产胞外多糖乳酸菌的筛选与鉴定

从生水牛乳中筛选出两株高产胞外多糖（EPS）的乳酸菌株LB2、LB7,经MRS肉汤培养基发酵后,菌液中的胞外多糖（EPS）产量分别达135 mg/L、148 mg/L,通过形态学、生理生化特征、API细菌鉴定系统、16S rRNA序列分析,鉴定出菌株LB2为植物乳杆菌（Lactobacillus plantarum）,LB7为类肠膜魏斯氏菌（Weissella paramesenteroides）。将其应用到水牛乳酸奶的发酵中,结果表明,植物乳杆菌LB2和类肠膜魏斯氏菌LB7均可用来发酵水牛乳酸奶,且能有效增加酸奶的黏度和胞外多糖产量,其黏度和EPS产量分别为4 050 mPa·s和149 mg/L。     

Streptococcus parauberis associated with modified atmosphere packaged broiler meat products and air samples from a poultry meat processing plant

Lactic acid bacteria (LAB) isolated from marinated or non-marinated, modified atmosphere packaged (MAP) broiler leg products and air samples of a large-scale broiler meat processing plant were identified and analyzed for their phenotypic properties. Previously, these strains had been found to be coccal LAB. However, the use of a 16 and 23S rRNA gene RFLP database had not resulted in species identification because none of the typically meat-associated LAB type strains had clustered together with these strains in the numerical analysis of the RFLP patterns. To establish the taxonomic position of these isolates, 16S rRNA gene sequence analysis, numerical analysis of ribopatterns, and DNA-DNA hybridization experiments were done. The 16S rRNA gene sequences of three isolates possessed the highest similarities (over 99%) with the sequence of S. parauberis type strain. However, in the numerical analysis of HindIII ribopatterns, the type strain did not cluster together with these isolates. Reassociation values between S. parauberis type or reference strain and the strains studied varied from 82 to 97%, confirming that these strains belong to S. parauberis. Unexpectedly, most of the broiler meat-originating strains studied for their phenotypical properties did not utilize lactose at all and the same strains fermented also galactose very weakly, properties considered atypical for S. parauberis. This is, to our knowledge, the first report of lactose negative S. parauberis strains and also the first report associating S. parauberis with broiler slaughter and meat products.     

酸马奶分离到的乳酸菌分子鉴定

为了研究内蒙古锡林郭勒盟传统酸马奶的乳酸菌构成,将从酸马奶样品中分离到的11株乳酸菌采用16 SrDNA鉴定方法进行分子鉴定。结果为:将所测菌株序列与标准菌株序列进行比对,菌株序列发现与瑞士乳杆菌菌株序列的同源性均较高,所测11株乳酸菌菌株均为瑞士乳杆菌。     

腌腊肉制品中乳酸菌的筛选鉴定及其在腊肠中的应用

为筛选适合传统腌腊肉制品的优良乳酸菌菌株,从多种农家自制传统腌腊肉制品中分离纯化出9株优势乳酸菌。通过发酵特性筛选,得到一株性状优良菌株10M-7,并制备该菌株的干粉发酵剂,以未接种发酵剂腊肠为对照,分析此发酵剂对腊肠感官品质和微生物变化的影响。结果表明,10M-7菌株具有良好的产酸特性和抑菌性能。根据形态学、生理生化特征和16S rRNA序列分析,鉴定其为植物乳杆菌,采用冷冻干燥法制备纯种发酵剂,并制作人工发酵腊肠。发酵剂组pH值在初期便迅速下降,且始终低于对照组;发酵剂组乳酸菌迅速生长繁殖,且葡萄球菌和大肠杆菌数量与对照组相比明显降低。感官评价表明,当添加量为10~4CFU/g原料肉时,能够很好地保持和改善产品风味,使产品整体感觉更好。     

眉山泡菜中乳酸菌的分离鉴定

目的：分析眉山泡菜的基本数据和乳酸菌的菌种构成。方法：从眉山市采集泡菜12 份,测定pH值、总酸度、盐度、乳酸菌计数,用16S rRNA序列分析法鉴定菌种。结果：样品pH值的范围是3.37～3.89,总酸度的范围是0.65～0.92 g/100 g（以乳酸计）,盐度的范围是4.16%～5.28%（以NaCl计）,MRS和M17乳酸菌计数分别是1.71～6.33、1.33～5.78（lg（CFU/g））。总酸度对乳酸菌计数影响最大。共分离鉴定出16 株乳酸菌：Lactobacillus fermentum（2 株）、Lactobacillus plantarum（3 株）、Lactobacillus brevis（2 株）、Lactobacillusacidophilus（1 株）、Lactobacillus casei（1 株）、Lactobacillus pentosus（1 株）、Lactobacillus delbrueckii（1 株）、Lactococcus lactis（3 株）、Pediococcus pentosaceus（2 株）。结论：眉山泡菜中乳酸菌存在多样性,实验结果为工业发酵生产泡菜积累了菌株。     

Distribution of lactic acid bacteria in garlic (Allium sativum) and green onion (Allium fistulosum) using SDS-PAGE whole cell protein pattern comparison and 16S rRNA gene sequence analysis

Distributions of lactic acid bacteria (LAB) in garlic and green onion samples as kimchi sub-ingredients were analyzed by comparing the SDS-PAGE whole cell protein patterns and 16S rRNA gene sequence analysis. In total, 245 LAB were isolated from 10 garlic samples and differentiated into 7 groups by comparing SDS-PAGE whole cell protein patterns. The groups were identified as Leuconostoc, Weissella, and Lactobacillus through the 16S rRNA gene sequence analysis. A total of 115 LAB were isolated from 7 green onion samples, differentiated into 6 groups, and identified as Weissella, Leuconostoc, and Lactococcus. Leuconostoc was the most dominated LAB in garlic and Weissella was the most dominated LAB in green onion. The LAB identified in this study was found as dominant microorganisms in kimchi. This result suggests the possible contribution of LAB in garlic and green onion to the bacterial microflora of kimchi, especially during early stage of fermentation.     

Diversity of lactic acid bacteria in suan-tsai and fu-tsai, traditional fermented mustard products of Taiwan

Fu-tsai and suan-tsai are spontaneously fermented mustard products traditionally prepared by the Hakka tribe of Taiwan. We chose 5 different processing stages of these products for analysis of the microbial community of lactic acid bacteria (LAB) by 16S rRNA gene sequencing. From 500 LAB isolates we identified 119 representative strains belonging to 5 genera and 18 species, including Enterococcus (1 species), Lactobacillus (11 species), Leuconostoc (3 species), Pediococcus (1 species), and Weissella (2 species). The LAB composition of mustard fermented for 3 days, known as the Mu sample, was the most diverse, with 11 different LAB species being isolated. We used sequence analysis of the 16S rRNA gene to identify the LAB strains and analysis of the dnaA, pheS, and rpoA genes to identify 13 LAB strains for which identification by 16S rRNA gene sequences was not possible. These 13 strains were found to belong to 5 validated known species: Lactobacillus farciminis, Leuconostoc mesenteroides, Leuconostoc pseudomesenteroides, Weissella cibaria, and Weissella paramesenteroides, and 5 possibly novel Lactobacillus species. These results revealed that there is a high level of diversity in LAB at the different stages of fermentation in the production of suan-tsai and fu-tsai.     

四川牦牛奶和曲拉中九株乳酸菌的分子鉴定

为准确鉴定分离自我国四川鲜牦牛奶和曲拉中9株乳酸菌到种水平,作者运用16S rDNA序列分析、recA基因特异扩增和hsp60-RFLP等多种分子技术对分离自我国四川地区鲜牦牛奶和曲拉中的9株乳酸菌进行分类鉴定。结果证实,16S rDNA序列分析法可将9株乳酸菌初步归类为植物乳杆菌群(4株),肠膜明串珠菌(4株),瑞士乳杆菌(1株)。由于16S rDNA序列分析法不能区分植物乳杆菌和戊糖乳杆菌,为了进一步鉴定植物乳杆菌群中的4株菌,继续采用recA基因特异扩增和hsp60-RFLP技术对其细分,结果表明recA基因特异扩增和hsp60-RFLP的方法均能很好地把植物乳杆菌群中的4株菌鉴定到种水平,且均为植物乳杆菌。     

甘南牧区犏牛酸奶中优良乳酸菌的分离与鉴定

从甘南牧区采集的犏牛酸奶中分离得到76 株乳酸菌。筛选得到3 株凝乳快速、产酸力强、凝乳质地优良的乳酸菌菌株,包括1 株球菌和2 株杆菌。采用16S rRNA基因序列比对分析,鉴定3 株乳酸菌分别是屎肠球菌（Enterococcus faecium）、德氏乳杆菌（Lactobacillus delbrueckii）和发酵乳杆菌（Lactobacillus fermentum）。通过球杆菌混合发酵实验,结果表明混合菌株发酵的产酸速率比单菌株发酵明显加快,且后酸化程度较弱,其感官质量也明显优于单菌发酵。     

High‐Throughput Isolation of Bacteriocin‐Producing Lactic Acid Bacteria,with Potential Application in the Brewing Industry

Lactic acid bacteria (LAB) were isolated from malted cereals by means of a high‐throughput screening approach and investigated for antimicrobial activity against a range of beer‐spoiling bacteria. Putative bacteriocin‐producing strains were identified by 16S rRNA analysis and the inhibitory compounds were partially characterized. Following determination of the inhibitory spectra of the strains, an unspeciated Lactobacillus sp. UCC128, with inhibitory activity against a range of beer‐spoiling strains was subjected to further characterization. A bacteriocin was purified from this strain and analyzed by mass spectrometry to determine the weight of the protein. The result indicated that the bacteriocin was highly similar to pediocin AcH/PA‐1 from Pediococcus acidilactici. The bacteriocin‐producers identified in this study have the potential to be used in the brewing industry to enhance the microbiological stability of beer in conjunction with hurdles already in place in the brewing process.     

东北酸菜中乳酸菌的分离鉴定与耐酸性菌株的筛选

为筛选出高耐酸性乳酸菌,通过形态学观察和随机扩增多态性DNA标记分析技术,对自然发酵酸菜中分离纯化的乳酸菌菌株进行初步鉴别,随后利用16S rDNA序列同源性分析进行种属鉴定,并筛选在pH 3.0条件下存活率较高的菌株。结果表明,72 株分离乳酸菌包括62 株乳杆菌和10 株乳球菌,其中有21 株菌的指纹图谱不相同,经鉴定,分别为乳肠球菌（Enterococcus lactis）、弯曲乳杆菌（Lactobacillus curvatus）、米曲霉乳杆菌（L. oryzae）、短乳杆菌（L. brevis）、副干酪乳杆菌（L. paracasei）、棒状乳杆菌（L. coryniformis）。pH 3.0条件下存活率在75%以上的菌株有8 株,管家基因rpoA序列同源性分析结果表明高耐酸性的两株菌株为植物乳杆菌（L. plantarum）,为开发功能性乳酸菌食品提供了一定理论支持。