title: Interaction of sesamol (3,4-methylenedioxyphenol) with tyrosinase and its effect on melanin synthesis.
abstract: Sesamin, sesamolin (lignans) and sesamol--from sesame seed (Sesamum indicum L.)--are known for their health promoting properties. We examined the inhibition effect of sesamol, a phenolic degradation product of sesamolin, on the key enzyme in melanin synthesis, viz. tyrosinase, in vitro. Sesamol inhibits both diphenolase and monophenolase activities with midpoint concentrations of 1.9 μM and 3.2 μM, respectively. It is a competitive inhibitor of diphenolase activity with a K(i) of 0.57 μM and a non-competitive inhibitor of monophenolase activity with a K(i) of 1.4 μM. Sesamol inhibits melanin synthesis in mouse melanoma B16F10 cells in a concentration dependant manner with 63% decrease in cells exposed to 100 μg/mL sesamol. Apoptosis is induced by sesamol, limiting proliferation. This study of the chemistry and biology of lignans, in relation to the mode of action of bioactive components, may open the door for drug applications targeting enzymes.
authors.affiliation: Department of Protein Chemistry & Technology, Central Food Technological Research Institute/CSIR, Mysore, Karnataka, India.
authors.forename: C Mahendra
authors.initials: CM
authors.lastname: Kumar
authors.forename: U V
authors.initials: UV
authors.lastname: Sathisha
authors.forename: Shylaja
authors.initials: S
authors.lastname: Dharmesh
authors.forename: A G Appu
authors.initials: AG
authors.lastname: Rao
authors.forename: Sridevi A
authors.initials: SA
authors.lastname: Singh
mesh_terms: D000363:Agaricales / Q000201:enzymology; D000818:Animals; D017209:Apoptosis / Q000187:drug effects; D052117:Benzodioxoles / Q000378:metabolism* / Q000494:pharmacology*; D020134:Catalytic Domain / Q000187:drug effects; D045744:Cell Line, Tumor; D003296:Cooking; D003300:Copper / Q000378:metabolism; D004791:Enzyme Inhibitors / Q000378:metabolism* / Q000494:pharmacology*; D017705:Lignans / Q000494:pharmacology; D008543:Melanins / Q000096:biosynthesis*; D051379:Mice; D014442:Monophenol Monooxygenase / Q000037:antagonists & inhibitors* / Q000737:chemistry / Q000378:metabolism*; D010088:Oxidoreductases / Q000037:antagonists & inhibitors; D010636:Phenols / Q000378:metabolism* / Q000494:pharmacology*; D011485:Protein Binding; D012715:Sesame Oil / Q000737:chemistry; D013057:Spectrum Analysis
chemical_list: D052117:Benzodioxoles; D004791:Enzyme Inhibitors; D017705:Lignans; D008543:Melanins; D010636:Phenols; D003300:Copper; D012715:Sesame Oil; C025583:sesamol; D010088:Oxidoreductases; C412191:monophenolase; D014442:Monophenol Monooxygenase