Development and Use of a Screening Procedure for Production of (alpha)-Acetolactate by Lactococcus lactis subsp. lactis biovar diacetylactis Strains.
نویسندگان
چکیده
A method was developed to screen and isolate mutagenized Lactococcus lactis subsp. lactis biovar diacetylactis strains accumulating (alpha)-acetolactate. This compound is accumulated by (alpha)-acetolactate decarboxylase-deficient strains and undergoes spontaneous degradation into diacetyl on agar plates. The diacetyl produced is detected by a colorimetric reaction yielding a red halo around the colonies.
منابع مشابه
Diacetyl and a-Acetolactate Overproduction by Lactococcus lactis subsp. lactis Biovar Diacetylactis Mutants That Are Deficient in a-Acetolactate Decarboxylase and Have a Low Lactate Dehydrogenase Activity
Lactococcus lactis subsp. lactis biovar diacetylactis strains are utilized in several industrial processes for producing the flavoring compound diacetyl or its precursor a-acetolactate. Using random mutagenesis with nitrosoguanidine, we selected mutants that were deficient in a-acetolactate decarboxylase and had low lactate dehydrogenase activity. The mutants produced large amounts of a-acetola...
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ورودعنوان ژورنال:
- Applied and environmental microbiology
دوره 63 2 شماره
صفحات -
تاریخ انتشار 1997