Studies On Pigment Production And Pigment's Character Of The Rhodotorular Glutinis

The carotenoid,a main kind of natural pigments which has been known to play an important role in keeping health and medical treatment.13-carotene is a typical carotenoid,which has been used as pigment and nutrition strengthener in food industry. In addition,its excellent antioxidant activity has been testified by many experiments.Some yeast strains producing carotenoid were separated from red lees in Fujian.At last,the B-5 stain was chosen as the test material,and it was identified as Rhodotorula glutinis var glutinis of Rhodotorular glutinis.By the orthogonai experiment,the optimal culture medium for pigment produce were decided as follows:glucose is 0.30%,NH₄NO₃ is 0.25%,tomato juice is 5mL,yeast power is 6g.It was studded that the extraction technics of the zymolytic production of Rhodotorular glutinis.In the experiment,three kinds of extraction method,namely ultrasonic,trituration and acid-heat method,were compared about extracting effect. The effect of ultrasonic damage was optimal.By orthogonal experiments,the extraction technics were as follows:the optimal organic solvent was acetone,the optimal temperature was 20℃,the optimal extraction time was 3 h,the optimal ratio of material to liquid was 1:40(m/v) and twice extracting was optimal.It were studied that the stability of the pigments in different illumination time and temperature,the best pH value,the effect of antiseptic,its reducing capacity as the contrast withα-tocopherol,and the antioxidation.The results were showed that the pigments had poor photostability and thermal stability,the optimal storage pH value was 6.0,the oxidation process could be inhibited by the antiseptic.The pigments had effective radical clearance ability,with the maximal scavenging activity to superoxide radical,with the second place to hydroxyl radical,and with the worst to hydrogen peroxide.Finally,the compositions of Rhodotorularglutinis pigments were separated and identified by thin-layer chromatography,fluorometry and spectrophotometer.Four components were separated and three of them belong toβ-carotene kind.