title: Extraction and quantitation of coumarin from cinnamon and its effect on enzymatic browning in fresh apple juice: a bioinformatics approach to illuminate its antibrowning activity.
abstract: Enzymatic browning by polyphenoloxidase (PPO) affects food quality and taste in fruits and vegetables. Thus, the study was designed to reduce browning in apple juice by coumarin. The ethanolic extract of cinnamon was prepared and its coumarin content was quantitated by HPLC, using authentic coumarin (AC) as standard. The effect of cinnamon extract (CE) and AC on enzymatic browning, its time dependent effects, and the specific activity of PPO and peroxidase (POD) were studied in apple juice. The docking of coumarin with PPO and POD was also performed to elucidate its antibrowning mechanism. The CE (73%) and AC (82%) showed better reduction in browning, maintained its antibrowning effect at all time points, and significantly (p < 0.05) reduced the specific activity of PPO and POD when compared with controls. Coumarin showed strong interaction with binding pockets of PPO and POD, suggesting its potential use as inhibitor to enzyme mediated browning in apple juice.
authors.affiliation: Department of Biotechnology, Rajalakshmi Engineering College, Thandalam, Chennai-602 105, Tamil Nadu, India.
authors.forename: Rajarajeshwari
authors.initials: R
authors.lastname: Thada
authors.forename: Shivashri
authors.initials: S
authors.lastname: Chockalingam
authors.forename: Ramesh Kumar
authors.initials: RK
authors.lastname: Dhandapani
authors.forename: Rajasekar
authors.initials: R
authors.lastname: Panchamoorthy
mesh_terms: D001628:Beverages / Q000032:analysis*; D004156:Catechol Oxidase / Q000037:antagonists & inhibitors / Q000737:chemistry / Q000378:metabolism; D002935:Cinnamomum zeylanicum / Q000737:chemistry*; D003116:Color; D003374:Coumarins / Q000032:analysis / Q000737:chemistry* / Q000302:isolation & purification / Q000378:metabolism; D004791:Enzyme Inhibitors / Q000032:analysis / Q000737:chemistry* / Q000302:isolation & purification / Q000378:metabolism; D005520:Food Preservatives / Q000032:analysis / Q000737:chemistry* / Q000302:isolation & purification / Q000378:metabolism; D063427:Food Quality; D005638:Fruit / Q000737:chemistry / Q000201:enzymology; D027845:Malus / Q000737:chemistry* / Q000201:enzymology; D008968:Molecular Conformation; D062105:Molecular Docking Simulation; D009195:Peroxidase / Q000037:antagonists & inhibitors / Q000737:chemistry / Q000378:metabolism; D024301:Plant Bark / Q000737:chemistry; D010936:Plant Extracts; D010940:Plant Proteins / Q000037:antagonists & inhibitors / Q000737:chemistry / Q000378:metabolism; D017365:Spices / Q000032:analysis*
chemical_list: D003374:Coumarins; D004791:Enzyme Inhibitors; D005520:Food Preservatives; D010936:Plant Extracts; D010940:Plant Proteins; C030123:coumarin; D004156:Catechol Oxidase; D009195:Peroxidase