Optimal culture conditions for pigment production of yeast isolated from Citrus paradisi

Autor: Yin-Feng Chen, 陳尹丰
Rok vydání: 2016
Druh dokumentu: 學位論文 ; thesis
Popis: 104
Expanding demands on natural pigment have driven the development of nutritive and functional natural food colorants. In among of that, red pigment has achieved rapid development nowadays. Production of pigments by fungi is characterized by various benefits such as short cycle, high recovery, climate-unaffected, optimal conditions on growth can be determined on temperature, pH, carbon and nitrogen sources. This study has utilized fruit and vegetable wastes as substrates for colorant production including wastes Penghu cactus, tomato, carrot, apple, grapefruit, lemon. Different color formation colonies with diameter 3-4 mm, and further classified according their appearances on mycelia, size, glossiness and colors were screened by plating. After verification on the ITS1 and ITS4 region of the screened colonies, it was classified as a species similar to Rhodotorula mucilaginosa. This strain is found highly to produce carotenoids. We have further optimized the condition for its growth. After inoculation 0.1%, a shaking condition of 125 rpm was carried out to reach 24 hour stationary phase under 27.5℃, pH 5.0 substrate, glucose 15 g/L and yeast extract at 2.5 g/L, highest colorant production was determined at1469.29 μg /L. The obtained colorant was further tested under short time high temperature (STHT) at 37℃, 6 hours, short time low temperature (STLT) at 10℃, 6 hours, and 22.5℃ conditions. It was discovered that temperature change during short time was unable to increase colorant production, however, a 22.5℃ would found to increase colorant production as high to 1533.27μg/g, this condition also found to prolong the production and reduce colorant degradation. This could be potential for bulk colorant production in near future.
Databáze: Networked Digital Library of Theses & Dissertations