title: Efficient regioselective acylation of quercetin using Rhizopus oryzae lipase and its potential as antioxidant.
abstract: The present investigation describes the regioselective enzymatic acylation of quercetin with ferulic acid using Rhizopus oryzae lipase. Optimization of reaction parameters resulted in 93.2% yield of the ester synthesized using 750IU of lipase in cyclo-octane at a temperature of 45°C. The reaction was successfully carried out upto 25g scale. The ester synthesized was analyzed by (1)H Nuclear magnetic resonance spectroscopy. The ester synthesized (quercetin ferulate) showed higher antiradical activity as compared to ascorbic acid using the 2,2-diphenyl-1-picrylhydrazyl radical method. These results on enzyme-catalyzed acylation of quercetin might be used to prepare and scale-up other flavonoids derivatives.
authors.affiliation: Department of Microbiology, University of Delhi South Campus, New Delhi 110021, India; Center of Innovative and Applied Bioprocessing (CIAB), C-127, IInd Floor, Phase 8, Industrial Area, S.A.S. Nagar, Mohali 160071, Punjab, India.
authors.forename: Vinod
authors.initials: V
authors.lastname: Kumar
authors.affiliation: Department of Microbiology, University of Delhi South Campus, New Delhi 110021, India.
authors.forename: Firdaus
authors.initials: F
authors.lastname: Jahan
authors.affiliation: Department of Microbiology, University of Delhi South Campus, New Delhi 110021, India.
authors.forename: Richi V
authors.initials: RV
authors.lastname: Mahajan
authors.affiliation: Department of Microbiology, University of Delhi South Campus, New Delhi 110021, India. Electronic address: rksmicro@yahoo.co.in.
authors.forename: Rajendra Kumar
authors.initials: RK
authors.lastname: Saxena
mesh_terms: D000215:Acylation; D000975:Antioxidants / Q000378:metabolism; D001713:Biphenyl Compounds; D002384:Catalysis; D008049:Lipase / Q000378:metabolism*; D010851:Picrates; D011794:Quercetin / Q000096:biosynthesis* / Q000737:chemistry; D012233:Rhizopus / Q000201:enzymology*
chemical_list: D000975:Antioxidants; D001713:Biphenyl Compounds; D010851:Picrates; D011794:Quercetin; C004931:1,1-diphenyl-2-picrylhydrazyl; D008049:Lipase
keywords: Quercetin; Quercetin ferulate; R. oryzae Lipase; Regioselective acylation