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Aim: The effects of detergent, ethanol and ethanol with plant meadowfoam oil on the growth of the red heterobasidomycete Xanthophyllomyces dendrorhous and on the production of astaxanthin (3,3′‐dihydroxy‐β,β‐carotene‐4,4′‐dione) and fatty acids in this red yeast were investigated. Methods and Results: Ethanol supplementation at a final concentration of 0.8% (v/v) caused an increase in the growth, astaxanthin production and fatty acid production of treated X. dendrorhous compared with untreated X. dendrorhous. Supplementation of meadowfoam oil with 0.8% ethanol further improved the growth and astaxanthin production of X. dendrorhous. Fatty acid compositions following supplementation with various concentrations of ethanol and oil were also analysed. With 0.8% ethanol supplementation, the ratio of linoleic acid (C18:2) and α‐linolenic acid (C18:3ω3, ALA) decreased. Conversely, with 1.8% ethanol supplementation, the ALA ratio increased. Conclusions: Ethanol can serve as a promoting factor for coproduction of astaxanthin and fatty acids in X. dendrorhous, whereas simultaneous supplementation of ethanol and meadowfoam oil can cause further astaxanthin production. Significance and Impact of Study: Astaxanthin is widely used in various functional products because of its antioxidant activity. This study shows that X. dendrorhous can coproduce astaxanthin and functional fatty acids at high levels following supplementation with ethanol. [ABSTRACT FROM AUTHOR]

Developing a use for the inedible parts of citrus, mainly peel, would have great environmental and economic benefits worldwide. Astaxanthin is a value-added fine chemical that affects fish pigmentation and has recently been used in healthcare products for humans, resulting in an increased demand. This study aimed to produce astaxanthin from a citrus, ponkan, peel extract using the yeast Xanthophyllomyces dendrorhous, which has the ability to use both pentose and hexose. Feeding on only ponkan peel extract enhanced X. dendrorhous growth and the concomitant astaxanthin production. Additionally, we determined that pectin and its arabinose content were the main substrate and sole carbon source, respectively, for X. dendrorhous growth and astaxanthin production. Thus, ponkan peel extract could become a valuable resource for X. dendrorhous–based astaxanthin production. Using citrus peel extract for microbial fermentation will allow the development of processes that produce value-added chemicals from agricultural byproducts. [ABSTRACT FROM AUTHOR]

The valuable marine carotenoid, astaxanthin, is used in supplements, medicines and cosmetics. In this study, crustacyanin, an astaxanthin-binding protein, was used to solubilize and concentrate astaxanthin. The recombinant crustacyanin of European lobster spontaneously formed an inclusion body when it was over-expressed in Escherichia coli. In this study, fusing the NusA-tag to the crustacyanin subunits made it possible to express in a soluble fraction and solubilize astaxanthin in aqueous solution. By cutting off the NusA-tag, the crustacyanin subunits generated the pure insoluble form, and captured and concentrated astaxanthin. Overall, the attaching and releasing NusA-tag method has the potential to supply solubilized carotenoids in aqueous solution and concentrated carotenoids, respectively. [ABSTRACT FROM AUTHOR]