title: Cinnamaldehyde inhibits enzymatic browning of cut lettuce by repressing the induction of phenylalanine ammonia-lyase without promotion of microbial growth.
abstract: Cinnamaldehyde treatment inhibited the browning of cut lettuce during cold storage. In this study, to clarify the mechanism of inhibitory action of cinnamaldehyde against the browning and to show its microbiological merit, its effect on the browning of cut lettuce was compared to that of mild heat treatment. Both cinnamaldehyde and mild heat treatments inhibited the induction of phenylalanine ammonia-lyase (PAL) activity because of cutting. As a result, the biosynthesis of polyphenols, which are substrates of polyphenol oxidase, was inhibited. This reduction of polyphenol synthesis caused the inhibition of the browning. Cinnamaldehyde treatment repressed the induction of PAL mRNA, while mild heat treatment did not repress its induction. The increase in microbes in cut lettuce treated with cinnamaldehyde was less than that treated with mild heat after 12 days.
authors.affiliation: Department of Nutrition and Food Science, Ochanomizu University , 2-1-1 Otsuka, Bunkyo-ku, Tokyo 112-8610, Japan.
authors.forename: Eriko
authors.initials: E
authors.lastname: Tanaka
authors.forename: Saya
authors.initials: S
authors.lastname: Okumura
authors.forename: Rikako
authors.initials: R
authors.lastname: Takamiya
authors.forename: Hitomi
authors.initials: H
authors.lastname: Hosaka
authors.forename: Yuko
authors.initials: Y
authors.lastname: Shimamura
authors.forename: Masatsune
authors.initials: M
authors.lastname: Murata
mesh_terms: D000171:Acrolein / Q000031:analogs & derivatives* / Q000494:pharmacology; D001419:Bacteria / Q000187:drug effects / Q000254:growth & development*; D015536:Down-Regulation / Q000187:drug effects*; D004791:Enzyme Inhibitors / Q000494:pharmacology*; D005419:Flavonoids / Q000096:biosynthesis; D005511:Food Handling; D005519:Food Preservation; D018545:Lactuca / Q000187:drug effects / Q000201:enzymology* / Q000235:genetics / Q000382:microbiology; D010636:Phenols; D010650:Phenylalanine Ammonia-Lyase / Q000037:antagonists & inhibitors / Q000235:genetics / Q000378:metabolism*; D010940:Plant Proteins / Q000037:antagonists & inhibitors / Q000235:genetics / Q000378:metabolism*; D059808:Polyphenols
chemical_list: D004791:Enzyme Inhibitors; D005419:Flavonoids; D010636:Phenols; D010940:Plant Proteins; D059808:Polyphenols; D000171:Acrolein; D010650:Phenylalanine Ammonia-Lyase; C012843:cinnamaldehyde