title: Astaxanthin preparation by fermentation of esters from Haematococcus pluvialis algal extracts with Stenotrophomonas species.
abstract: Natural astaxanthin (Ax) is an additive that is widely used because of its beneficial biochemical functions. However, the methods used to produce free Ax have drawbacks. Chemical saponification methods produce several by-products, and lipase-catalyzed hydrolysis methods are not cost effective. In this study, a bacterial strain of Stenotrophomonas sp. was selected to enzymatically catalyze the saponification of Ax esters to produce free all-trans-Ax. Through single-factor experiments and a Box-Behnken design, the optimal fermentation conditions were determined as follows: a seed culture age of 37.79 h, an inoculum concentration of 5.92%, and an initial broth pH of 6.80. Under these conditions, a fermentation curve was drawn, and the optimal fermentation time was shown to be 60 h. At 60 h, the degradation rate of the Ax esters was 98.08%, and the yield of free all-trans-Ax was 50.130 μg/mL. © 2016 American Institute of Chemical Engineers Biotechnol. Prog., 32:649-656, 2016.
authors.affiliation: College of Food Science and Engineering, Ocean University of China, Qingdao, 266003, China.
authors.forename: Hao
authors.initials: H
authors.lastname: Dong
authors.affiliation: College of Food Science and Engineering, Ocean University of China, Qingdao, 266003, China.
authors.forename: Xuemin
authors.initials: X
authors.lastname: Li
authors.affiliation: College of Food Science and Engineering, Ocean University of China, Qingdao, 266003, China.
authors.forename: Changhu
authors.initials: C
authors.lastname: Xue
authors.affiliation: College of Food Science and Engineering, Ocean University of China, Qingdao, 266003, China.
authors.forename: Xiangzhao
authors.initials: X
authors.lastname: Mao
mesh_terms: D000460:Chlorophyta / Q000737:chemistry* / Q000378:metabolism*; D004952:Esters / Q000737:chemistry / Q000378:metabolism*; D005285:Fermentation; D020588:Stenotrophomonas / Q000737:chemistry / Q000378:metabolism*; D024341:Xanthophylls / Q000096:biosynthesis / Q000737:chemistry
chemical_list: D004952:Esters; D024341:Xanthophylls; C005948:astaxanthine
keywords: Ax esters; H. pluvialis oil; Stenotrophomonas sp; fermentation; free all-trans-Ax