Molecular design of antibrowning agents.
Tyrosinase inhibitory and antioxidant activity of gallic acid and its series of alkyl chain esters were investigated. All inhibited the oxidation of L-3,4-dihydroxyphenylalanine (L-DOPA) catalyzed by mushroom tyrosinase. However, gallic acid and its short alkyl chain esters were oxidized as substrates yielding the colored oxidation products. In contrast, the long alkyl chain esters inhibited the enzyme activity without being oxidized. This indicates that the carbon chain length is associated with their tyrosinase inhibitory activity, presumably by interacting with the hydrophobic protein pocket in the enzyme. On the other hand, the esters, regardless their carbon chain length, showed potent scavenging activity on the autoxidation of linoleic acid and 1,1-diphenyl-2-p-picryhydrazyl (DPPH) radical, suggesting that the alkyl chain length is not related to the activity. The effects of side-chain length of gallates in relation to their antibrowning activity are studied.
Kubo
I
I
Department of Environmental Science, Policy and Management, University of California, Berkeley, California 94720-3112, USA. ikubo@uclink4.berkeley.edu
Kinst-Hori
I
I
Kubo
Y
Y
Yamagiwa
Y
Y
Kamikawa
T
T
Haraguchi
H
H
D000363:Agaricales / Q000201:enzymology; D000975:Antioxidants / Q000138:chemical synthesis* / Q000494:pharmacology; D015195:Drug Design; D005519:Food Preservation; D005707:Gallic Acid / Q000031:analogs & derivatives* / Q000138:chemical synthesis* / Q000494:pharmacology; D007700:Kinetics; D014442:Monophenol Monooxygenase / Q000037:antagonists & inhibitors*; D010084:Oxidation-Reduction; D013329:Structure-Activity Relationship
D000975:Antioxidants; D005707:Gallic Acid; D014442:Monophenol Monooxygenase