Superoxide Dismutase Activity and Ethanol Respiration in a Fungi Resistance to Ethanol Monascus sp. MM

Abstract

ABSTRACT Monascus sp. MM was a contaminant fungus isolated from museum specimen preserved with ethanol 70 %. In order to verify role of superoxide dismutase (SOD) in protecting cell from ethanol toxicity during ethanol metabolism, SOD activities of Monascus sp.MM and a Monmcus sp. NGK, which was isolated fiom fermented red rice (angkak), were compared. When fungus was grown with glucose, CuIZn-SOD activity of Monascus sp., MM was 7.1 times of thht of Monascus sp. NGK. Whereas in ethanol medium, CuIZn-SOD activity of Monarcus sp. MM was 24.6 times of that in Monascus sp. NGK. Induction of CuIZn-SOD Monmcus sp. MM by ethanol was not observed. Compared with Mn-SOD, activity of CuIZn- SOD was markedly important (I 0 times of Mn-SOD when fungi grown with ethanol; 12 times when the fungi grown with glucose). The data indicated that Cu/Zn-SOD might play an important role in protecting cell fiom ethanol toxicity during ethanol metabolism. Ethanol respiration rate of Monascus sp. MM was also important since O2 consumption and ethanol degradation rates were clearly higher than that of Monascus sp. NGK. Keywords: Monarcw sp., superoxide dismutase, respiration, ethanol resistance.