title: A comparison on the preparation of hot water extracts from Chlorella pyrenoidosa (CPEs) and radical scavenging and macrophage activation effects of CPEs.
abstract: Development of hot water extracts of Chlorella pyrenoidosa (CPE) may help in the reduction of the cost involved in C. pyrenoidosa-based biofuel production. The current extraction conditions of CPE greatly vary and the CPE-related research are developing rather slowly. To find an effective preparation method, in the present study, we have prepared CPEs using high pressures, ultrasonication, and enzymolysis, and we have compared the yields, general ingredients, and bioactivities of these products. The yields of the high pressure and enzymolysis methods were more than 25%. CPE-a, which has been prepared under an extra 0.1 MPa pressure in an autoclave, was rich in protein, and it had the strongest absorbance at 260 and 280 nm, whereas CPE-c and CPE-d, which were prepared via the enzymolysis of cellulase and pectinase, had higher sugar content. The CPEs had no inhibitory influence on the formation of advanced glycation end products, and their metal chelating activities were poor. However, all the products had significant positive effects on in vitro free radical scavenging and macrophage growth promotion. Hydroxyl radicals were scavenged in a concentration-dependent manner by CPE-a, and the cultured macrophage Ana-1 proliferated to 162.98% of the control when CPE-a was administrated at 200 μg mL(-1). Furthermore, phagocytic activity and intracellular nitric oxide levels of Ana-1 were significantly enhanced with the administration of CPE-a. In brief, our results suggest that hot water extraction with high pressure is an effective method for preparing high value-added bio-products from C. pyrenoidosa, which have strong potential for use in free radical scavenging and macrophage activation.
authors.affiliation: State Key Laboratory of Bioreactor Engineering, East China University of Science and Technology, Shanghai 200237, People's Republic of China. hysygli@163.com.
authors.forename: Xiuyuan
authors.initials: X
authors.lastname: Zhuang
authors.forename: Daojing
authors.initials: D
authors.lastname: Zhang
authors.forename: Wen
authors.initials: W
authors.lastname: Qin
authors.forename: Jia
authors.initials: J
authors.lastname: Deng
authors.forename: Hui
authors.initials: H
authors.lastname: Shan
authors.forename: Liming
authors.initials: L
authors.lastname: Tao
authors.forename: Yuanguang
authors.initials: Y
authors.lastname: Li
mesh_terms: D000818:Animals; D002460:Cell Line; D005591:Chemical Fractionation / Q000295:instrumentation / Q000379:methods*; D002708:Chlorella / Q000737:chemistry*; D016166:Free Radical Scavengers / Q000302:isolation & purification* / Q000494:pharmacology*; D008262:Macrophage Activation / Q000187:drug effects*; D008264:Macrophages / Q000187:drug effects* / Q000276:immunology; D051379:Mice; D010587:Phagocytosis; D014465:Ultrasonics / Q000379:methods*
chemical_list: D016166:Free Radical Scavengers