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Lipase-Catalyzed Synthesis of Wax Ester

ABSTRACT Five immobilized lipases were tested for their ability to catalyze the alcoholysis reaction of triolein and oleyl alcohol to produce oleyl oleate, a wax ester. Lipase AH, LipasePS-C, Lipozyme and Novozyme showed relatively higher specific activities. Lipozyme and Novozyme were then used to investigate the effect of continuously controlled water activity and the effect of adding silica gel on the reaction system. It was found that the reaction system using Lipozyme and Novozyme were best carried out at aw=0.33. The amount of silica gel needed for both Lipozyme and Novozyme to reach optimal yield of ester are 0.25 g and 0.50 g; respectively. A reaction system at optimum condition was carried out and the percentage yield of oleyl oleate produced was 75.66%. Abstrak. Lima jenis lipase sekatgerak telah diuji kebolehannya untuk memangkinkan tindakbalas alkoholisis diantara triolein dan alkohol olil untuk menghasilkan olil oleat, sejenis ester lilin. Lipase AH, Lipase PS-C, Lipozim dan Novozim telah menunjukkan aktiviti spesifik yang tinggi. Lipozim dan Novozim seterusnya telah digunakan untuk mengkaji kesan aktiviti air berterusan dan kesan penambahn gel silika keatas sistem tindakbals. Hasil yang didapati telah menunjukkan bahawa tindakbalas terbaik bagi sistem yang bermangkinkan Lipozim dan Novozim adalah pada nilai aktiviti air = 0.33. Manakala amaun gel silika yang diperlukan didalam sistem tindakbalas untuk mencapai keadaan optimum adalah 0.25g untuk Lipozim dan 0.50g untuk Novozim. Suatu sistem tindakbalas telah dijalankan pada keadaan optimum dan peratus hasil bagi olil oleat yang diperolehi adalah 75.66%.

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Oct 8, 2014