title: A chiral ligand exchange CE system for monitoring inhibitory effect of kojic acid on tyrosinase.
abstract: A facile chiral ligand exchange capillary electrophoresis (CLE-CE) system with Zn(II)-L-alanine as the chiral selector in the presence of β-cyclodextrin has been developed for enantioseparation of dansyl amino acids. The influence of the key factors, such as buffer pH, the ratio of Zn (II) to ligand, the concentration of β-cyclodextrin and the concentration of the complex, were investigated in detail when D, L-Tyr and D, L-Thr were selected as the model analytes. The proposed method showed favorable quantitative analysis property of dansyl D, L-tyrosine with good linearity (r(2)≥0.999) and reproducibility (RSD≤3.8%), then, it was applied in studying the activity of tyrosinase through the determination of L-tyrosine concentration variation after being incubated with the enzyme. Further, the inhibitory efficiency of kojic acid and soy sauce on the tyrosinase was investigated. The IC50 of kojic acid obtained from the sigmoidal inhibitory curve was 21.35 μM. The results imply that the proposed CLE-CE system has the potential in exploring the activity of enzyme and screening the inhibitors of enzyme.
authors.affiliation: Beijing National Laboratory for Molecular Sciences, Key Lab of Analytical Chemistry for Living Biosystems, Institute of Chemistry, Chinese Academy of Sciences, No. 2 Zhongguancun Beiyijie, Beijing 100190, China; College of Food Sciences and Engineering, Shandong Agricultural University, Tai'an, Shandong 271018, China.
authors.forename: Bing-bing
authors.initials: BB
authors.lastname: Sun
authors.forename: Li
authors.initials: L
authors.lastname: Qi
authors.forename: Xiao-yu
authors.initials: XY
authors.lastname: Mu
authors.forename: Juan
authors.initials: J
authors.lastname: Qiao
authors.forename: Ming-lin
authors.initials: ML
authors.lastname: Wang
mesh_terms: D000409:Alanine / Q000737:chemistry; D003619:Dansyl Compounds / Q000737:chemistry*; D019075:Electrophoresis, Capillary / Q000379:methods*; D004791:Enzyme Inhibitors / Q000032:analysis* / Q000737:chemistry; D006801:Humans; D006863:Hydrogen-Ion Concentration; D008024:Ligands; D014442:Monophenol Monooxygenase / Q000037:antagonists & inhibitors* / Q000737:chemistry; D011753:Pyrones / Q000032:analysis* / Q000737:chemistry; D011994:Recombinant Proteins / Q000737:chemistry; D015203:Reproducibility of Results; D012996:Solutions; D045730:Soy Foods / Q000032:analysis; D013237:Stereoisomerism; D013912:Threonine / Q000737:chemistry; D014443:Tyrosine / Q000737:chemistry*; D015032:Zinc / Q000737:chemistry; D047392:beta-Cyclodextrins / Q000737:chemistry
chemical_list: D003619:Dansyl Compounds; D004791:Enzyme Inhibitors; D008024:Ligands; D011753:Pyrones; D011994:Recombinant Proteins; D012996:Solutions; D047392:beta-Cyclodextrins; D013912:Threonine; D014443:Tyrosine; C011890:kojic acid; D014442:Monophenol Monooxygenase; D015032:Zinc; C031215:betadex; D000409:Alanine
keywords: AAs; CE; CLE; Capillary electrophoresis; Chiral ligand exchange; Dns-AA; Dns-Cl; Kojic acid; LOD; LOQ; RSD; Resolution; Rs; Thr; Tris; Tris(hydroxymethyl)aminomethane; Tyr; Tyrosinase inhibitor; amino acids; capillary electrophoresis; chiral ligand exchange; dansyl choride; dansylated-AA; l-Ala; l-alanine; limit of detection; limit of quantitation; relative standard deviation; threonine; tyrosine; β-CD; β-cyclodextrin