A Comparative Study on Properties and Proteolytic Components of Papaya Peel and Latex Proteases
Phanuphong Chaiwut, Sarote Nitsawang, Lalida Shank, and Pawinee Kanasawud* Author for corresponding; e-mail address: lalida_shank@yahoo.com
Volume :Vol.34 No.1 (JANUARY 2007)
Research Article
DOI:
Received: 24 July 2006, Revised: -, Accepted: 23 November 2006, Published: -
Citation: Chaiwut P., Nitsawang S., Shank L. and Kanasawud P., A Comparative Study on Properties and Proteolytic Components of Papaya Peel and Latex Proteases, Chiang Mai Journal of Science, 2007; 34(1): 109-118.
Abstract
Proteases from papaya peels were extracted with water followed by precipitation with ethanol and 57.6% yield was obtained. Their maximum hydrolysis of casein comparing to proteases from latex were similar in temperature but different in pH. Both of papaya proteases were fully activated by 5 mM cysteine, the peel enzymes were activated 1.6 times higher than latex enzymes. The peel proteases are also more stable in pH ≥ 8 and at 80oC than the latex proteases. Cathodic polyacrylamide gel electrophoresis and in situ proteolysis verified that papaya peel proteases are composed of papain as a major component, chymopapain, and possible two proteases which are absent in crude papain. Separation by anodic polyacrylamide gel electrophoresis and in situ proteolysis illustrated that proteases from papaya peels contained a protease with pI less than 8.3. Anion-exchange chromatography indicated that papaya peel proteases consisted of a number of proteins and proteases different from those found in papaya proteases.