Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
3
pubmed:dateCreated
2000-6-15
pubmed:abstractText
Addition of branched-chain amino acids (BCAA) or an inhibitor of the BCAA biochemical pathways during fermentation of milk with a lac(-) mutant of Lactobacillus delbrueckii subsp. bulgaricus and Streptococcus thermophilus strongly influenced the formation of two aroma-impact compounds, 2,3-butanedione and 2,3-pentanedione, as well as their direct precursors 2-acetolactate and 2-acetohydroxybutyrate. This suggests a connection between vicinal diketone formation and BCAA biosynthesis in yogurt bacteria. A recently developed static-and-trapped headspace technique combined with gas chromatography-mass spectrometry demonstrated incorporation of (13)C from [U-(13)C(6)]-D-glucose and [U-(13)C(4)]-L-threonine into both vicinal diketones. For 2,3-butanedione, glucose is the major precursor via pyruvate and activated acetaldehyde. For 2, 3-pentanedione, L-threonine is a precursor via 2-ketobutyrate, but glucose is the major contributor via activated acetaldehyde and, possibly, also via 2-ketobutyrate, which is a degradation product of 3-methylaspartate, an intermediate in glutamate synthesis.
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Mar
pubmed:issn
0021-8561
pubmed:author
pubmed:issnType
Print
pubmed:volume
48
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
724-31
pubmed:dateRevised
2006-11-15
pubmed:meshHeading
pubmed:year
2000
pubmed:articleTitle
Vicinal diketone formation in yogurt: (13)C precursors and effect of branched-chain amino acids.
pubmed:affiliation
Nestlé Research Center, NESTEC Ltd., P.O. Box 44, Vers-chez-les-Blanc, 1000 Lausanne 26, Switzerland.
pubmed:publicationType
Journal Article