Shahanaz Khatun
Department of Biochemistry, University of Rajshahi, Rajshahi 6205, Bangladesh
Nurul Absar
Department of Biochemistry, University of Rajshahi, Rajshahi 6205, Bangladesh
M. Ashraduzzaman
Department of Biochemistry, University of Rajshahi, Rajshahi 6205, Bangladesh
ABSTRACT
Polyphenoloxidase (PPO), a highly active oxidative enzyme in Sajna leaves at mature stage was purified by ion exchange chromatography on DEAE-cellulose followed by CM-cellulose. The purified enzyme was monomer in nature and its molecular weight was estimated to be 56,000 and 55,500 by gelfiltration and SDS-PAGE respectively. The enzyme appeared to be a single polypeptide chain as revealed by SDS-PAGE either in presence or absence of reducing agent. The enzyme has following characteristics : optimum pH 6.2, optimum temperature 32°C, Km value 0.047M against catechol as substrate and maximum absorption 279 nm. The activity of the enzyme was enhanced by Ca2+ and Cu2+ but its activity lost completely in presence of ascorbic acid, EDTA, KCN and NaHSO3.
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How to cite this article
Shahanaz Khatun, Nurul Absar and M. Ashraduzzaman, 2001. Purification, Characterization and Effect of Physico-chemical Agents on Stability of Polyphenoloxidase from Sajna (Moringa oleifere L.) Leaves at Mature Stage. Pakistan Journal of Biological Sciences, 4: 1129-1132.
DOI: 10.3923/pjbs.2001.1129.1132
URL: https://scialert.net/abstract/?doi=pjbs.2001.1129.1132
DOI: 10.3923/pjbs.2001.1129.1132
URL: https://scialert.net/abstract/?doi=pjbs.2001.1129.1132
REFERENCES
- Andrews, P., 1965. The gel-filtration behaviour of proteins related to their molecular weights over a wide range. Biochem. J., 96: 595-606.
CrossRefDirect Link - Partington, J.C. and G.P. Bolwell, 1996. Purification of polyphenoloxidase free of the storage protein patatin from potato tuber. Phytochemistry, 42: 1499-1502.
Direct Link - Lowry, O.H., N.J. Rosebrough, A.L. Farr and R.J. Randall, 1951. Protein measurement with the folin phenol reagent. J. Biol. Chem., 193: 265-275.
CrossRefPubMedDirect Link - Mowlah, G. and S. ltoo, 1982. Quantitative changes in guava polyphenols and the polyphenoloxidase (PPO) at different stages of maturation, ripening and storage. Nippon Shokuhin Kogyo Gakkaishi, 29: 413-417.
Direct Link - Owusu-Ansah, Y.J., 1989. Polyphenol oxidase in wild rice (Zizania palustris). J. Agric. Food Chem., 37: 901-904.
CrossRefDirect Link - Soderhall, I., 1995. Properties of carrot polyphenoloxidase. Phytochemistry, 39: 33-38.
CrossRefDirect Link