title: Tyrosinase inhibition kinetic studies of standardized extract of Berberis aristata.
abstract: The stem bark and wood of Berberis aristata DC (Daruharidra) are one of the principal ingredients of traditional skin lighting and exfoliating scrub preparation in India. The standardised extract of B. aristata was screened to evaluate their in vitro antityrosinase activity and inhibition kinetics. Phytochemical and pharmacological studies were carried out with different solvent fractions of the methanol extract of B. aristata (MEBA). RP-HPLC analysis was used to determine the berberine content in extract and fractions of B. aristata. MEBA showed maximum berberine content. Extract and fractions of B. aristata contain the maximum amount of alkaloids than other constituents. In tyrosinase inhibition assay, MEBA was found to possess highest dose-dependent monophenolase and moderate diphenolase activity. The enzyme kinetic study revealed that MEBA possessed mixed type inhibition of monophenolase activity of tyrosinase. These bioactivities indicate that the MEBA has antihyperpigmentation potential in human skin.
authors.affiliation: a Department of Pharmaceutical Technology, School of Natural Product Studies , Jadavpur University , Kolkata , India.
authors.forename: Rajarshi
authors.initials: R
authors.lastname: Biswas
authors.affiliation: a Department of Pharmaceutical Technology, School of Natural Product Studies , Jadavpur University , Kolkata , India.
authors.forename: Pulok K
authors.initials: PK
authors.lastname: Mukherjee
authors.affiliation: a Department of Pharmaceutical Technology, School of Natural Product Studies , Jadavpur University , Kolkata , India.
authors.forename: Sushil K
authors.initials: SK
authors.lastname: Chaudhary
mesh_terms: D000470:Alkaloids / Q000032:analysis; D001599:Berberine / Q000032:analysis; D028142:Berberis / Q000737:chemistry*; D002851:Chromatography, High Pressure Liquid / Q000592:standards; D004353:Drug Evaluation, Preclinical / Q000379:methods; D004791:Enzyme Inhibitors / Q000737:chemistry / Q000494:pharmacology*; D007194:India; D007700:Kinetics; D014442:Monophenol Monooxygenase / Q000037:antagonists & inhibitors*; D010936:Plant Extracts / Q000032:analysis / Q000737:chemistry* / Q000494:pharmacology*; D012997:Solvents / Q000737:chemistry
chemical_list: D000470:Alkaloids; D004791:Enzyme Inhibitors; D010936:Plant Extracts; D012997:Solvents; D001599:Berberine; D014442:Monophenol Monooxygenase
keywords: Berberis aristata; RP-HPLC; antityrosinase; berberine; mixed-inhibition kinetics