Optimization of the silanization conditions for the immobilization of papain onto white lahar

Date

11-2009

Degree

Bachelor of Science in Chemistry

College

College of Arts and Sciences (CAS)

Abstract

ABSTRACT

ORAIS, ANGELICA ESPIRITU. College of Arts and Science, University of the Philippines Los Banos. October 2009. OPTIMIZATION OF THE SILANIZATION CONDITIONS FOR THE IMMOBILIZATION OF PAPAIN ONTO LAHAR.

Adviser: Dr. Veronica C. Sabularse

Lahar samples were obtained from Tarlac, Pampanga which is an area located near Mt. Pinatubo. Lahar obtained from this arm consists of black and white lahar. Pretreatment of lahar was conducted in order to separate black and white lahar to obtain an entirely homogeneous sample of white lahar. SEM analysis was conducted to determine the physical characteristics of black and white lahar. Electron micrographs showed that white lahar has greater porosity than black lahar making it more suitable as a support for enzyme immobilization. The treated white lahar was silanized under optimum conditions of 15% 3-aminopropyltriethoxysilane at 75 °C for 2 hours and activated using 2.5% glutaraldehyde. Chemical tests and FT-1R analyses confirmed attachment of silane and glutaraldehyde to lahar. The amount of papain immobilized on the activated lahar was 38.7 %. The free and lahar-immobilized papain exhibited maximal activity at pH 6.5, a temperature of 65 °C, and a substrate concentration of 0.75 mg/ml. The Michaelis constant, Km, of the immobilized papain was 3.28 x leg casein/ 100m1 and that of the free papain was 6.38 x 10' g casein/ 100m1. Maximal velocities, \trim, of the immobilized and free papain were found to be 16.39 and 11.11 (mmol tyr/mI)/min, respectively. While the turnover numbers, k,,,, were found to be 1092.7 and 740.7 (rrimol)/min-mg for immobilized and free papain respectively. Papain stability towards continuous use, daily use and weekly use were also determined. The immobilization of papain gave stability to the enzyme. The immobilized enzyme still exhibited activity after 10 hours of continuous use. Activity was also observed after daily use for 5 consecutive days. Likewise, lahar-immobilized papain remained active after 4 weeks of consecutive use.

Language

English

Location

UPLB Main Library Special Collections Section (USCS)

Call Number

LG 993.5 2009 C4 O73

Document Type

Thesis

This document is currently not available here.

Share

COinS