Linked Life Data

12430774

Source:http://linkedlifedata.com/resource/pubmed/id/12430774

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
1
pubmed:dateCreated
2002-11-14
pubmed:abstractText
Lactobacillus fermentum Ogi E1 is an amylolytic heterofermentative lactic acid bacterium previously isolated from ogi, a Benin maize sourdough. In the present study, the effect of different pH between 3.5 and 6.0 on starch fermentation products and alpha-amylase production was investigated. Whereas a pH of 5.0 was optimum for specific growth rate and lactic acid production, growth was only slightly affected at suboptimal pH of 4.0 and 6.0. Over a pH range of 6.0 to 3.5, yields of product formation from substrate and of biomass relative to ATP were constant. These results showed that L. fermentum Ogi E1 was particularly acid tolerant, and well adapted to the acid conditions that develop during natural fermentation of cereal doughs. This acid tolerance may partly explain the dominance of L. fermentum in various traditional African sourdoughs. Surprisingly, alpha-amylase production, unlike growth, dropped dramatically when the strain was cultivated at pH 4.0 with starch. With maltose as substrate, the yield of alpha-amylase relative to biomass remained unchanged at pH 4.0 and 5.0, unlike that observed with starch. Based on the distribution of enzyme activity between extra- and intracellular fractions and fermentation kinetics, it appears that starch was first hydrolyzed into dextrins by alpha-amylase activity, and maltose was produced from dextrins by extracellular enzyme activity, transferred into the cell and then hydrolyzed into glucose by intracellular alpha-glucosidase.
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Jan
pubmed:issn
0168-1605
pubmed:author
pubmed:issnType
Print
pubmed:day
15
pubmed:volume
80
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
77-87
pubmed:dateRevised
2008-11-21
pubmed:meshHeading
pubmed:year
2003
pubmed:articleTitle
Study of starch fermentation at low pH by Lactobacillus fermentum Ogi E1 reveals uncoupling between growth and alpha-amylase production at pH 4.0.
pubmed:affiliation
Institut de Recherche pour le Développement, Unité R106 Nutrition, Alimentation, Sociétiés, Montpellier, France.
pubmed:publicationType
Journal Article, Research Support, Non-U.S. Gov't