检索结果-南通市图书馆

The Citrate Metabolism in Homo-and Heterofermentative LAB:A Selective Means of Becoming Dominant over Other Microorganisms in Complex Ecosystems

引用

Food and Nutrition Sciences 2014年第10期5卷 953-969页

作者： gemelas laetitia Degraeve Pascal Demarigny Yann Isara-Lyon AgrapoleFood Microbiology LaboratoryBIODYMIALyonFrance Lyon 1 University Research Laboratory in Industrial Engineering Food—BIODYMIA EA 373Bourg-en-BresseFrance

The citrate metabolism has been extensively studied in lactic acid bacteria (LAB) for its aroma compound production. Among the 4-carbon (C4) by-products obtained from citrate fermentation, diacetyl is one of the better known products for its contribution to the buttery aroma of dairy products. A lot of documents deal with ways to improve diacetyl concentration in food matrices. Apart from these organoleptic advantages, in a microbial ecosystem, the citrate metabolism gives selective advantages to citrate positive microorganisms. Citrate metabolism allows the LAB to use another carbon source for their growth, withstand acidic conditions and generate a “proton motive force” (PMF). Moreover, the citrate/glucid co-metabolism leads to the fast release of organic compounds known for having bacteriostatic effects. Under specific conditions, the C4?pathway liberates diacetyl which is bacteriostatic. In this review we first describe the citrate metabolism and the enzymes involved in the two homo- and heterofermentative LABLc diacetylactisandLeuconostocspp. Moreover, the way to shift the metabolic pathway toward the production of aromatic compounds is discussed for both of these fermentative types of bacteria. Finally, the selective advantages of citrate metabolism for LAB in complex microbial ecosystems are delineated.

关键词： Citrate Metabolism Lactococcus lactis subsp.lactis biovar.diacetylactis Leuconostoc spp. Complex Microbial Ecosystems Homo-and Heterofermentative Lactic Acid Bacteria

来源：

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

A Rapid Electrophoresis Method on Agarose Gel to Characterise Dairy Protein Aggregates

引用

Food and Nutrition Sciences 2018年第4期9卷 325-334页

作者： laetitia gemelas Pascal Degraeve Marion Morand Arnaud Hallier Yann Demarigny Univ Lyon ISARA Lyon Université Lyon 1 BioDyMIA (Bioingénierie et Dynamique Microbienne aux Interfaces Alimentaires) EA n&#176 3733 ISARA Agrap&#244 le Lyon France Univ Lyon Université Lyon 1 ISARA Lyon BioDyMIA (Bioingénierie et Dynamique Microbienne aux Interfaces Alimentaires) EA n&#176 3733 IUT Lyon 1 technopole Alimentec rue Henri de Boissieu BOURG-EN-BRESSE France General Mills Inc One Global Dairy Vienne Technical Center Chemin des Mines Vienne France ISARA Lyon Chemistry Laboratory Lyon France

Heat treatment of milk may cause whey proteins and caseins to form aggregates. These soluble and micellar aggregates and their other properties (size, composition, shape, etc.) can affect the techno-functionalities to the milk, conferring interesting or negative features depending on the application in dairy industries. In this study, we propose a new approach to characterise those protein aggregates. SDS-agarose electrophoresis is followed by the calculation of a retention factor (Rf) for each protein spot. Rf allows milk aggregates to be compared qualitatively under the same conditions. This method could be transposed to the dairy industry for a better knowledge of the milk subsequent to heat treatment.

关键词： Heat Treatment of Milk Dairy Protein Aggregates Agarose Gel Electrophoresis

来源：

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Selective Lactococcus Enumeration in Raw Milk

引用

Food and Nutrition Sciences 2013年第9期4卷 49-58页

作者： laetitia gemelas Véronique Rigobello Mai Huong Ly-Chatain Yann Demarigny Isara-Lyon Unité BioDyMIALyonFrance

The Lactococcus diversity in cow and goat raw milk was investigated. To do so, a protocol had to be established for the specific enumeration of lactococci. Eight agar media and one control medium were analysed to compare their proficiency in evaluating the Lactococcus population in raw milk: M17 Nal, Elliker, modified Elliker, PCA + milk, modified KCA, modified Chalmers, Turner, FSDA. The M17 medium was used as reference. Eighteen pure strains were tested on these media for their selectivity towards lactococci: six Lactococcus species or subspecies, three Leuconostoc, three Enterococcus, two Lactobacillus, one Streptococcus thermophilus, one Pseudomonas fluorescens, one Escherichia coli and one Staphylococcus aureus. All these bacteria were chosen for their regular presence in raw milk. The KCA medium proved to be the most selective towards lactococci, on condition that 1) we discriminated the colonies using the catalase test and 2) we subtracted the Enterococcus population counted on BEA. However, it was not possible to separate the Streptococcus from the Lactococcus colonies on KCA. The “Lactococcus-like” population including these two genera was estimated at a mean level of 3.18 log(cfu)/mL and 4.14 log(cfu)/mL in cow and goat raw milk respectively. This is consistent with the data already published.

关键词： Lactococcus Culture Media Raw Milk LAB Modified KCA

来源：

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

欢迎您,

建议与咨询留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

时间限定

文献类型

馆藏选择

核心期刊

语言

文献类型

帮助

文字说明：

检索规则说明：

检索范例：

分类表

所选分类

限定检索结果

文献类型

馆藏范围

日期分布

学科分类号

主题

机构

作者

语言

在线全文

在线全文

在线全文

请选择保存的检索档案：

请选择收藏分类：

通借通还

欢迎您,

建议与咨询 留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

时间限定

文献类型

馆藏选择

核心期刊

语言

文献类型

帮助

文字说明：

检索规则说明：

检索范例：

分类表

所选分类

限定检索结果

文献类型

馆藏范围

日期分布

学科分类号

主题

机构

作者

语言

在线全文

在线全文

在线全文

请选择保存的检索档案： 新增检索档案 确定 取消

请选择收藏分类： 新增自定义分类 确定 取消

通借通还

建议与咨询留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

请选择保存的检索档案：

请选择收藏分类：