TY - JOUR
T1 - The effects of extracellular pH and hydroxycinnamic acids influence the intracellular pH of Brettanomyces bruxellensis DSM 7001
AU - Campolongo, Simona
AU - Siegumfeldt, Henrik
AU - Aabo, Thomas Ask
AU - Cocolin, Luca
AU - Arneborg, Nils
PY - 2014
Y1 - 2014
N2 - Brettanomyces bruxellensis yeast produces ethyl phenols, which cause wine spoilage and severe economic losses. Ethyl phenols are produced by a class of polyphenols that are present in grapes and musts, called hydrocinnamic acids, which are capable of inhibiting yeasts and bacteria. The viability and intracellular pH changes in B. bruxellensis DSM 7001, in response to extracellular pH, as well as to the presence of an energy source and hydroxycinnamic acids, have been investigated in this paper by means of Fluorescent Ratio Imaging Microscopy (FRIM). The results show that B. bruxellensis DSM 7001 is able to maintain viability and increase its pH gradient with decreasing external pH values, whereas it is not able to maintain a pH gradient at high external pH values (i.e. pH 8) and, as a consequence, dies. The growth inhibitory effects of ferulic and p-coumaric acid do not seem to be caused by a weak-acid inhibition mechanism, since both acids induce a similar, or even higher, intracellular acidification at a high external pH than at a low external pH. The results presented have to be confirmed by using other strains of B. bruxellensins in order to validate the outcomes obtained in this study.
AB - Brettanomyces bruxellensis yeast produces ethyl phenols, which cause wine spoilage and severe economic losses. Ethyl phenols are produced by a class of polyphenols that are present in grapes and musts, called hydrocinnamic acids, which are capable of inhibiting yeasts and bacteria. The viability and intracellular pH changes in B. bruxellensis DSM 7001, in response to extracellular pH, as well as to the presence of an energy source and hydroxycinnamic acids, have been investigated in this paper by means of Fluorescent Ratio Imaging Microscopy (FRIM). The results show that B. bruxellensis DSM 7001 is able to maintain viability and increase its pH gradient with decreasing external pH values, whereas it is not able to maintain a pH gradient at high external pH values (i.e. pH 8) and, as a consequence, dies. The growth inhibitory effects of ferulic and p-coumaric acid do not seem to be caused by a weak-acid inhibition mechanism, since both acids induce a similar, or even higher, intracellular acidification at a high external pH than at a low external pH. The results presented have to be confirmed by using other strains of B. bruxellensins in order to validate the outcomes obtained in this study.
KW - Brettanomyces bruxellensis
KW - Fluorescent Ratio Imaging Microscopy (FRIM)
KW - Hydroxycinnamic acid
KW - Weak acid inhibition mechanism
U2 - 10.1016/j.lwt.2014.06.006
DO - 10.1016/j.lwt.2014.06.006
M3 - Journal article
AN - SCOPUS:84907599080
SN - 0023-6438
VL - 59
SP - 1088
EP - 1092
JO - Lebensmittel - Wissenschaft und Technologie
JF - Lebensmittel - Wissenschaft und Technologie
IS - 2, Part 1
ER -