title: Effect of active oxygen species on the productivity of torularhodin by Rhodotorula glutinis No. 21.
abstract: The effect of active oxygen species on the productivity of torularhodin, an effective antioxidant, by soil yeast, Rhodotorula glutinis no. 21, was examined. Methylene blue, methyviologen and AAPH [2,2'-azobis(2-amidinopropane) dihydrochloride] were used as generators of singlet oxygen, superoxide anion radicals and peroxy radicals, respectively. All of them indicated effectiveness at a dose of 1.0 x 10(-10) to 3.0 x 10(-6) M. Addition of these generators to the culture medium had almost no influence on the biosynthesis of beta-carotene, whereas it had marked enhancement on those of torulene and torularhodin. Production of uric acid by xanthineoxidase remained unchanged at a torularhodin concentration of up to 100 microM. This result suggests that torularhodin does not directly affect the productivity of superoxide anions. It has been proved that torularhodin has a more potent effect on the scavenging of peroxyl radicals and inhibits substrate degradation by singlet oxygen more effectively than beta-carotene does. Continuous addition of methylene blue enhanced the torularhodin accumulation more markedly than single addition.
authors.affiliation: Department of Agricultural Chemistry Faculty of Agriculture, Kinki University, 3327-204 Nakamachi, Nara 631-8505, Japan. hideyuki-sakaki@senju.co.jp
authors.forename: Hideyuki
authors.initials: H
authors.lastname: Sakaki
authors.forename: Hidesato
authors.initials: H
authors.lastname: Nochide
authors.forename: Sadao
authors.initials: S
authors.lastname: Komemushi
authors.forename: Wataru
authors.initials: W
authors.lastname: Miki