title: Countercurrent flow of supercritical anti-solvent in the production of pure xanthophylls from Nannochloropsis oculata.
abstract: This study examined pilot scaled elution chromatography coupled with supercritical anti-solvent precipitation (using countercurrent flow) in generating zeaxanthin-rich particulates from a micro-algal species. Ultrasonic agitated acetone extract subjected to column fractionation successfully yielded a fraction containing 349.4 mg/g of zeaxanthin with a recovery of 85%. Subsequently, supercritical anti-solvent (SAS) precipitation of the column fraction at 150 bar and 343 K produced submicron-sized particulates with a concentration of 845.5mg/g of zeaxanthin with a recovery of 90%. Experimental results from a two-factor response surface method SAS precipitation indicated that purity, mean size and morphology of the precipitates were significantly affected by the flow type configuration, feed flow rate and injection time.
authors.affiliation: Department of Chemical Engineering, National Chung Hsing University, 250 Kuo-Kuang Road, Taichung 40227, ROC Taiwan.
authors.forename: Yueh-Cheng
authors.initials: YC
authors.lastname: Cho
authors.forename: Yuan-Chuen
authors.initials: YC
authors.lastname: Wang
authors.forename: Chwen-Jen
authors.initials: CJ
authors.lastname: Shieh
authors.forename: Justin Chun-Te
authors.initials: JC
authors.lastname: Lin
authors.forename: Chieh-Ming J
authors.initials: CM
authors.lastname: Chang
authors.forename: Esther
authors.initials: E
authors.lastname: Han
mesh_terms: D002245:Carbon Dioxide / Q000737:chemistry; D011232:Chemical Precipitation; D025924:Chromatography, Supercritical Fluid / Q000379:methods*; D003377:Countercurrent Distribution / Q000379:methods*; D058086:Microalgae / Q000737:chemistry; D010316:Particle Size; D013010:Sonication; D058009:Stramenopiles / Q000737:chemistry*; D024341:Xanthophylls / Q000302:isolation & purification*
chemical_list: D024341:Xanthophylls; D002245:Carbon Dioxide