Diacetyl production by different strains of Lactococcus lactis subsp. lactis var. diacetylactis and Leuconostoc spp.

SummarySeveral strains of Lactococcus lactis subsp. lactis var. diacetylactis and Leuconostoc spp. were compared for product formation from citrate in milk cultures. Most strains produced acetoin and butanediol. Some strains derived from buffer starter cultures produced, in addition, α-acetolactate. Lactococcus lactis strain C17, which produced acetoin and butanediol but no α-acetolactate in culture, was compared physiologically with L. lactis strain Ru4, which produced only α-acetolactate. Activities of enzymes involved in citrate metabolism were almost identical in both strains, with the exception of α-acetolactate decarboxylase, which was missing in strain Ru4. The formation of α-acetolactate, acetoin and diacetyl was further analysed in cell-free extracts. α-Acetolactate synthase activity saturated at a high pyruvate concentration (100 mm). This is in agreement with the observed accumulation of pyruvate externally, and probably internally, during α-acetolactate, acetoin and butanediol production by L. lactis cells.

[1]  Hillier Aj,et al.  [63] l-Lactate dehydrogenase,1 FDP-activated, from Streptococcus cremoris , 1982 .

[2]  K. Jordan,et al.  Production of acetolactate by Streptococcus diacetylactis and Leuconostoc spp. , 1988, Journal of Dairy Research.

[3]  W. Westerfield.  A colorimetric determination of blood acetoin. , 1945, The Journal of biological chemistry.

[4]  T. Cogan.  Constitutive nature of the enzymes of citrate metabolism in Streptococcus lactis subsp. diacetylactis , 1981, Journal of Dairy Research.

[5]  J. Stadhouders,et al.  Determination of diacetyl in dairy products containing alpha-acetolactic acid , 1984 .

[6]  Jeroen Hugenholtz,et al.  Citrate Fermentation by Lactococcus and Leuconostoc spp , 1991, Applied and environmental microbiology.

[7]  T. Cogan,et al.  Citric acid metabolism in hetero- and homofermentative lactic acid bacteria , 1976, Applied and environmental microbiology.

[8]  W. Verhue,et al.  Study of the Citrate Metabolism of Lactococcus lactis subsp. lactis Biovar Diacetylactis by Means of 13C Nuclear Magnetic Resonance , 1991, Applied and environmental microbiology.

[9]  F. C. Størmer.  2,3-Butanediol biosynthetic system in Aerobacter aerogenes. , 1975, Methods in Enzymology.

[10]  W. Sandine,et al.  Improved Medium for Lactic Streptococci and Their Bacteriophages , 1975, Applied microbiology.

[11]  M. M. Bradford.  A rapid and sensitive method for the quantitation of microgram quantities of protein utilizing the principle of protein-dye binding. , 1976, Analytical biochemistry.

[12]  Z. Puhan,et al.  Technology of mesophilic fermented milk , 1988 .

[13]  F. Z. Hegazi,et al.  Acetoin and Diacetyl Production by Homo- and Heterofermentative Lactic Acid Bacteria. , 1983, Journal of food protection.

[14]  P. Frey,et al.  Synthesis and properties of 2-acetylthiamin pyrophosphate: an enzymatic reaction intermediate. , 1987, Biochemistry.

[15]  Hideki Suzuki,et al.  Differences between Lactobacillus casei subsp. casei 2206 and Citrate-Positive Lactococcus lactis subsp. lactis 3022 in the Characteristics of Diacetyl Production , 1991, Applied and environmental microbiology.

[16]  J. Pien,et al.  Le dosage du diactyle dans les beurres (Mthode d'expertise) , 1937 .

[17]  Z. Libudzisz,et al.  Production of diacetyl and acetoin by lactic acid bacteria , 1982 .

[18]  E. Collins,et al.  Diacetyl Biosynthesis in Streptococcus diacetilactis and Leuconostoc citrovorum , 1968, Journal of bacteriology.

[19]  M. Rogosa,et al.  A MEDIUM FOR THE CULTIVATION OF LACTOBACILLI , 1960 .

[20]  J. Visser,et al.  Pyruvate dehydrogenase complex from Bacillus. , 1982, Methods in enzymology.

[21]  J. Snoep,et al.  Isolation, characterization, and physiological role of the pyruvate dehydrogenase complex and alpha-acetolactate synthase of Lactococcus lactis subsp. lactis bv. diacetylactis , 1992, Journal of bacteriology.