CENTRO DE REFERENCIA PARA LACTOBACILOS
Unidad Ejecutora - UE
Effect of L-malic acid on the B-glycosidase enzyme production in microorganisms from wines
LOTO CAMPOS, I.E.; SAGUIR F.M.; MANCA DE NADRA M. C.
Lugar: Mendoza Argentina; Año: 2007 vol. 31 p. 301 - 301
Volatile compounds from odorless, non volatile-glycosides can be released by enzymatic hydrolysis, thus enhancing the aromatic wines profile. We previously demonstrated that the strains of Oenococcus oeni ST and Pediococcus pentosaceus 12p posed b-glycosidase activity in cellular suspensions. The aim of this work was to investigate in the same strains of O. oeni y P. pentosaceus the effect of L-malic acid on the b-glycosidase enzyme synthesis. Cells were cultivated in MRS medium with 15% of tomato juice (TJ) and in the same medium+1.5 g/l of L-malic acid at 30ºC. b-glycosidase activity was measured in cellular suspensions utilizing p-nitrofenyl-b-D-glycopiranoside as substrate. L-malic acid addition to the medium increased 14.1% the O. oeni ST growth but did not modify the 12p strain development. Enzymatic activities were maxima in the cellular suspensions obtained at the end of exponential growth phase. In the ST strain, when L-malic acid was added to the MRS+TJ medium decreased 35% the maximum specific activity (485.2 nmol/mg/h). By contrast in P. pentosaceus 12p the L-malic acid increased 40% the maximum specific activity (520 nmol/mg/h). In conclusion, in the fermented grape must, O. oeni ST responsible microorganism for conducing malolactic fermentation in north Argentinean wines has higher potentialities to expresser the b-glycosidase enzyme when the L- malic acid decarboxylation had been concluded.