Document Type : Original Article
Authors
1 Asistant professor of Biochemistry, Department Of Biology, Payame Noor University,
2 Department of Chemistry, Payame Noor University, IRAN
Abstract
In order to better understand how to prevent enzymatic greenning, it is important to understand kinetic properties of polyphenol oxidase. we investigated the effect of SDS on the rate of catechol oxidation by small cherry tomato partial purified PPO. PPO activity increased with increasing SDS concentration. The most effective concentration of SDS was 0.8, 1 and 1.25 mM in according to pH and type of substrate, where the measured activity was 0.074 and 0.247 units/mg.protein at pH 6.7 and 0.159 and 0.118 unit/mg.protein at pH 8 for catechol and pyrogallol, respectively. The activation of field small cherry PPO increased linearly with the SDS concentration up to 1 – 1.5 mM and decreased thereafter. The activity of small cherry PPO was also enhanced 1.7-fold by exposure to SDS at pH 8.0 in presence of catechol, 1.8-fold by exposure to SDS at pH 8.0 in presence of pyrogallol, 2.3-fold by exposure to SDS at pH 6.7 in presence of catechol and 2.6-fold by exposure to SDS at pH 6.7 in presence of pyrogallol. Therefore sodium dodesyl sulphate is an activator of polyphenol oxidase that can probably change latent form of enzyme to active form, so increases the activity of polyphenol oxidase
Keywords
Fraignier MP, Marques L, Fleuriet A, Macheix JJ (1995) Biochemical and immunochemical characteristics of polyphenol oxidases from different fruits of Prunus. J Agric Food Chem 43:2375– 2380.
Laveda, E. Nunez-Delicado, F. Garcia-Carmona and A. Sanchez-Ferrer.(2001) Proteolytic activation of latent Paraguaya peach PPO. Characterization of monophenolase activity. J. Agric. Food Chem. 49(2):1003-8.
Li L, Steffens J C (2002) Overexpression of polyphenol oxidase in transgenic tomato plants results in enhanced bacterial disease resistance. Planta 215: 239-247.
Lowry OH, Rosebrough NJ, Farr AL, Randall RJ (1951). Protein measurement with the Folin-Phenol reagents. J. Biol. Chem, 193: 265-27.
Kenten R (1958) Latent phenolase in extracts of broad bean (Vicia faba L.). 1. Activation by anionic wetting agents. Biochem. J. 68, 244–251.
Kessler A, Baldwin I (2002) Plant responses to insect herbivory: the emerging molecular analysis. Annu. Rev. Plant Biol. 53, 299–328.
Mayer A, Harel E (1979) Polyphenol oxidases in plants – review. Phytochemistry 18, 193–215.
Jiang H, Shi C, Xie Y, Xu X, Liu Q (2003) Activation of tobacco leaf polyphenol oxidase by sodium dodecyl sulfate. Indian J. Biochem. Biophys. 40, 350–353.
Melo GA, Shimizu MM, Mazzafera P (2006) Polyphenoloxidase activity in coffee leaves and its role in resistance against the coffee leaf miner and coffee leaf rust. Phytochemistry 67: 277-285.
Moore BM, Flurkey WH (1990) Sodium dodecyl activation of a plant polyphenol oxidase. J Biol Chem 265:4982–4988.
Robinson S, Dry I (1992) Broad bean leaf polyphenol oxidase is a 60-kilodalton protein susceptible to proteolytic cleavage. Plant Physiol. 99, 317–323.
Robb D, Mapson L, Swain T (1964) Activation of the latent tyrosinase of broad bean. Nature (London) 201, 503–504.
Swain T, Mapson L, Robb D (1966) Activation of Vicia faba (L.) tyrosinase as effected by denaturing agents. Phytochemistry 5, 469–482.
Saeidian S, Keyhani E, Keihani J (2007). Polyphenol oxidase activity in dormant saffron (Crocus Sativus L.) corm. Acta Physiol Plant, 29: 463-471.
Saeidian S, Keyhani E, Keihani J (2007). Effect of Ionic Detergents, Nonionic Detergents, and Chaotropic Agents on Polyphenol Oxidase Activity from Dormant Saffron (Crocus sativus L.) Corms. J. Agric. Food Chem, 55(9): 3713-3719.
Saeidian S (2013). Partial purification and characterisation of polyphenol oxidase from tomatoes (solanum lycopersicum). International journal of Advanced Biological and Biomedical Research, Volume 1, Issue 6,
2013: 637-648
)