title: Optimization of acidic extraction of astaxanthin from Phaffia rhodozyma.
abstract: Optimization of a process for extracting astaxanthin from Phaffia rhodozyma by acidic method was investigated, regarding several extraction factors such as acids, organic solvents, temperature and time. Fractional factorial design, central composite design and response surface methodology were used to derive a statistically optimal model, which corresponded to the following optimal condition: concentration of lactic acid at 5.55 mol/L, ratio of ethanol to yeast dry weight at 20.25 ml/g, temperature for cell-disruption at 30 degrees C, and extraction time for 3 min. Under this condition, astaxanthin and the total carotenoids could be extracted in amounts of 1294.7 microg/g and 1516.0 microg/g, respectively. This acidic method has advantages such as high extraction efficiency, low chemical toxicity and no special requirement of instruments. Therefore, it might be a more feasible and practical method for industrial practice.
authors.affiliation: School of Biosystem Engineering and Food Science, Zhejiang University, Hangzhou 310029, China. nihui1973@yahoo.com.cn
authors.forename: Hui
authors.initials: H
authors.lastname: Ni
authors.forename: Qi-he
authors.initials: QH
authors.lastname: Chen
authors.forename: Guo-qing
authors.initials: GQ
authors.lastname: He
authors.forename: Guang-bin
authors.initials: GB
authors.lastname: Wu
authors.forename: Yuan-fan
authors.initials: YF
authors.lastname: Yang
mesh_terms: D001487:Basidiomycota / Q000737:chemistry*; D006851:Hydrochloric Acid; D019344:Lactic Acid; D024341:Xanthophylls / Q000302:isolation & purification
chemical_list: D024341:Xanthophylls; D019344:Lactic Acid; C005948:astaxanthine; D006851:Hydrochloric Acid