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High yield of wax ester synthesized from cetyl alcohol and octanoic acid by lipozyme RMIM and Novozym 435.

Kuo CH, Chen HH, Chen JH, Liu YC, Shieh CJ - Int J Mol Sci (2012)

Bottom Line: Response surface methodology (RSM) and 5-level-4-factor central composite rotatable design (CCRD) are employed to evaluate the effects of reaction time (1-5 h), reaction temperature (45-65 °C), substrate molar ratio (1-3:1), and enzyme amount (10%-50%) on the yield of cetyl octanoate.Using RSM to optimize the reaction, the maximum yields reached 94% and 98% using Lipozyme(®) RMIM and Novozym(®) 435, respectively.Novozym(®) 435 proves to be a more efficient biocatalyst than Lipozyme(®) RMIM.

View Article: PubMed Central - PubMed

Affiliation: Biotechnology Center, National Chung Hsing University, 250 Kuo-kuang Road, Taichung 402, Taiwan; E-Mail: jahomekuo@gmail.com.

ABSTRACT
Wax esters are long-chain esters that have been widely applied in premium lubricants, parting agents, antifoaming agents and cosmetics. In this study, the biocatalytic preparation of a specific wax ester, cetyl octanoate, is performed in n-hexane using two commercial immobilized lipases, i.e., Lipozyme(®) RMIM (Rhizomucor miehei) and Novozym(®) 435 (Candida antarctica). Response surface methodology (RSM) and 5-level-4-factor central composite rotatable design (CCRD) are employed to evaluate the effects of reaction time (1-5 h), reaction temperature (45-65 °C), substrate molar ratio (1-3:1), and enzyme amount (10%-50%) on the yield of cetyl octanoate. Using RSM to optimize the reaction, the maximum yields reached 94% and 98% using Lipozyme(®) RMIM and Novozym(®) 435, respectively. The optimum conditions for synthesis of cetyl octanoate by both lipases are established and compared. Novozym(®) 435 proves to be a more efficient biocatalyst than Lipozyme(®) RMIM.

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Response surface plots showing the relationships between cetyl octanoate yield and reaction parameters for Novozym® 435: (a) reaction time and enzyme amount; (b) reaction time and temperature; (c) reaction time and substrate molar ratio.
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f3-ijms-13-11694: Response surface plots showing the relationships between cetyl octanoate yield and reaction parameters for Novozym® 435: (a) reaction time and enzyme amount; (b) reaction time and temperature; (c) reaction time and substrate molar ratio.

Mentions: Reaction times and enzyme amount were investigated in the range of the reaction time of 1–5 h and enzyme amount of 10%–50%, respectively. Figure 3a represents the effect of varying reaction time and enzyme amount on esterification efficiency at a substrate molar ratio of 2:1 and a reaction temperature of 55 °C. At the lowest reaction time of 1 h with the lowest enzyme amount of 10%, molar conversion was only 44%. A reaction with an enzyme amount of 35% and a reaction time of 3.75 h increased the yield to 97%. Figure 3b shows the effects of reaction time, temperature and their mutual interaction on cetyl octanoate synthesis at a substrate molar ratio of 2:1 and an enzyme amount of 30%. With the highest reaction temperature of 65 °C and reaction time of 3.75 h, a cetyl octanoate yield of 99% was obtained. Whereas, when the reaction temperature was decreased to 45 °C and the reaction time shortened to 1 h, only 66% yield remained. Figure 3c shows the effect of varying reaction time and substrate molar ratio on esterification at a reaction temperature of 50 °C and an enzyme amount of 20%. The yield increased with increasing substrate molar ratio and reaction time. With the highest reaction time of 5 h and the highest substrate molar ratio of 3:1, cetyl octanoate yield of 95% was obtained. These results from Figure 3 reveal that reaction time, temperature, substrate molar ratio and enzyme amount are all important variables for synthesis of cetyl octanoate catalyzed by Candida antarctica (Novozym® 435). Unlike Lipozyme® RMIM, the esterification yield increased as the substrate molar ratio increased using Novozym® 435. Since excess acid in the reaction might cause denaturation of the enzyme and loss of its activity [29], our results indicated that the Novozym® 435 was more tolerant to acidic conditions than Lipozyme® RMIM.


High yield of wax ester synthesized from cetyl alcohol and octanoic acid by lipozyme RMIM and Novozym 435.

Kuo CH, Chen HH, Chen JH, Liu YC, Shieh CJ - Int J Mol Sci (2012)

Response surface plots showing the relationships between cetyl octanoate yield and reaction parameters for Novozym® 435: (a) reaction time and enzyme amount; (b) reaction time and temperature; (c) reaction time and substrate molar ratio.
© Copyright Policy - open-access
Related In: Results  -  Collection

License 1 - License 2
Show All Figures
getmorefigures.php?uid=PMC3472770&req=5

f3-ijms-13-11694: Response surface plots showing the relationships between cetyl octanoate yield and reaction parameters for Novozym® 435: (a) reaction time and enzyme amount; (b) reaction time and temperature; (c) reaction time and substrate molar ratio.
Mentions: Reaction times and enzyme amount were investigated in the range of the reaction time of 1–5 h and enzyme amount of 10%–50%, respectively. Figure 3a represents the effect of varying reaction time and enzyme amount on esterification efficiency at a substrate molar ratio of 2:1 and a reaction temperature of 55 °C. At the lowest reaction time of 1 h with the lowest enzyme amount of 10%, molar conversion was only 44%. A reaction with an enzyme amount of 35% and a reaction time of 3.75 h increased the yield to 97%. Figure 3b shows the effects of reaction time, temperature and their mutual interaction on cetyl octanoate synthesis at a substrate molar ratio of 2:1 and an enzyme amount of 30%. With the highest reaction temperature of 65 °C and reaction time of 3.75 h, a cetyl octanoate yield of 99% was obtained. Whereas, when the reaction temperature was decreased to 45 °C and the reaction time shortened to 1 h, only 66% yield remained. Figure 3c shows the effect of varying reaction time and substrate molar ratio on esterification at a reaction temperature of 50 °C and an enzyme amount of 20%. The yield increased with increasing substrate molar ratio and reaction time. With the highest reaction time of 5 h and the highest substrate molar ratio of 3:1, cetyl octanoate yield of 95% was obtained. These results from Figure 3 reveal that reaction time, temperature, substrate molar ratio and enzyme amount are all important variables for synthesis of cetyl octanoate catalyzed by Candida antarctica (Novozym® 435). Unlike Lipozyme® RMIM, the esterification yield increased as the substrate molar ratio increased using Novozym® 435. Since excess acid in the reaction might cause denaturation of the enzyme and loss of its activity [29], our results indicated that the Novozym® 435 was more tolerant to acidic conditions than Lipozyme® RMIM.

Bottom Line: Response surface methodology (RSM) and 5-level-4-factor central composite rotatable design (CCRD) are employed to evaluate the effects of reaction time (1-5 h), reaction temperature (45-65 °C), substrate molar ratio (1-3:1), and enzyme amount (10%-50%) on the yield of cetyl octanoate.Using RSM to optimize the reaction, the maximum yields reached 94% and 98% using Lipozyme(®) RMIM and Novozym(®) 435, respectively.Novozym(®) 435 proves to be a more efficient biocatalyst than Lipozyme(®) RMIM.

View Article: PubMed Central - PubMed

Affiliation: Biotechnology Center, National Chung Hsing University, 250 Kuo-kuang Road, Taichung 402, Taiwan; E-Mail: jahomekuo@gmail.com.

ABSTRACT
Wax esters are long-chain esters that have been widely applied in premium lubricants, parting agents, antifoaming agents and cosmetics. In this study, the biocatalytic preparation of a specific wax ester, cetyl octanoate, is performed in n-hexane using two commercial immobilized lipases, i.e., Lipozyme(®) RMIM (Rhizomucor miehei) and Novozym(®) 435 (Candida antarctica). Response surface methodology (RSM) and 5-level-4-factor central composite rotatable design (CCRD) are employed to evaluate the effects of reaction time (1-5 h), reaction temperature (45-65 °C), substrate molar ratio (1-3:1), and enzyme amount (10%-50%) on the yield of cetyl octanoate. Using RSM to optimize the reaction, the maximum yields reached 94% and 98% using Lipozyme(®) RMIM and Novozym(®) 435, respectively. The optimum conditions for synthesis of cetyl octanoate by both lipases are established and compared. Novozym(®) 435 proves to be a more efficient biocatalyst than Lipozyme(®) RMIM.

Show MeSH
Related in: MedlinePlus