title: Inhibitory effects of hinokitiol on tyrosinase activity and melanin biosynthesis and its antimicrobial activities.
abstract: The inhibitory effects of hinokitiol, a constituent of the woody oils isolated from Cupressaceae heartwood, on mushroom tyrosinase and melanin formation in B16 melanoma cells as well as its antimicrobial activity were investigated. Our results showed that hinokitiol could strongly inhibit both monophenolase activity and diphenolase activity of the enzyme and the inhibition was reversible. The IC(50) values were estimated as 9.67 μM for monophenolase activity and 0.21 μM for diphenolase activity. The lag time of the monophenolase activity was not obviously lengthened by the compound. Kinetic analyses showed that the inhibition mechanism of hinokitiol was a mixed-type inhibition of the diphenolase activity. Hinokitiol effectively inhibited both cellular tyrosinase activity and melanin biosynthesis in B16 melanoma cells with significant cytotoxicity. Furthermore, it was found that hinokitiol could inhibit the proliferation of Salmonella enteritidis, Escherichia coli, Bacillus subtilis, Staphyloccocus aureus, Klebsiella pneumoniae, and Ralstonia solanacearum to different extents. This research may widen the use of hinokitiol in the fields of food preservation, depigmentation, and insecticide use.
authors.affiliation: Agricultural Bioresource Research Institute, Fujian Academy of Agricultural Sciences, Fuzhou, China.
authors.forename: Yu-Jing
authors.initials: YJ
authors.lastname: Zhu
authors.forename: Ling
authors.initials: L
authors.lastname: Qiu
authors.forename: Jing-Jing
authors.initials: JJ
authors.lastname: Zhou
authors.forename: Hua-Yun
authors.initials: HY
authors.lastname: Guo
authors.forename: Yong-Hua
authors.initials: YH
authors.lastname: Hu
authors.forename: Zhi-Cong
authors.initials: ZC
authors.lastname: Li
authors.forename: Qin
authors.initials: Q
authors.lastname: Wang
authors.forename: Qing-Xi
authors.initials: QX
authors.lastname: Chen
authors.forename: Bo
authors.initials: B
authors.lastname: Liu
mesh_terms: D000363:Agaricales / Q000201:enzymology; D000818:Animals; D000900:Anti-Bacterial Agents / Q000494:pharmacology*; D045744:Cell Line, Tumor; D049109:Cell Proliferation / Q000187:drug effects; D002470:Cell Survival / Q000187:drug effects; D004791:Enzyme Inhibitors / Q000494:pharmacology*; D005520:Food Preservatives / Q000494:pharmacology; D005656:Fungal Proteins / Q000037:antagonists & inhibitors / Q000378:metabolism; D006090:Gram-Negative Bacteria / Q000187:drug effects; D016937:Gram-Positive Endospore-Forming Rods / Q000187:drug effects; D007700:Kinetics; D008543:Melanins / Q000096:biosynthesis*; D008544:Melanocytes / Q000187:drug effects / Q000201:enzymology; D008546:Melanoma, Experimental; D051379:Mice; D008826:Microbial Sensitivity Tests; D014442:Monophenol Monooxygenase / Q000037:antagonists & inhibitors* / Q000378:metabolism; D039821:Monoterpenes / Q000494:pharmacology*; D013379:Substrate Specificity; D014334:Tropolone / Q000031:analogs & derivatives* / Q000494:pharmacology
chemical_list: D000900:Anti-Bacterial Agents; D004791:Enzyme Inhibitors; D005520:Food Preservatives; D005656:Fungal Proteins; D008543:Melanins; D039821:Monoterpenes; D014334:Tropolone; D014442:Monophenol Monooxygenase; C009479:beta-thujaplicin