Limits...
Immobilization, Regiospecificity Characterization and Application of Aspergillus oryzae Lipase in the Enzymatic Synthesis of the Structured Lipid 1,3-Dioleoyl-2-Palmitoylglycerol.

Cai H, Li Y, Zhao M, Fu G, Lai J, Feng F - PLoS ONE (2015)

Bottom Line: The enzymatic synthesis of 1,3-dioleoyl-2-palmitoylglycerol (OPO), one of the main components of human milk fats, has been hindered by the relatively high cost of sn-1,3-specific lipases and the deficiency in biocatalyst stability.The sn-1,3-specific lipase from Aspergillus oryzae (AOL) is highly and efficiently immobilized with the polystyrene-based hydrophobic resin D3520, with a significant 49.54-fold increase in specific lipase activity compared with the AOL powder in catalyzing the synthesis of OPO through the acidolysis between palm stearin and oleic acid (OA).Immobilized AOL D3520, as the biocatalyst, was used for the enzymatic synthesis of the structured lipid OPO through the acidolysis between palm stearin and OA.

View Article: PubMed Central - PubMed

Affiliation: College of Biosystems Engineering and Food Science, Zhejiang University, Hangzhou, China; Zhejiang Key Laboratory for Agro-Food Processing, Zhejiang University, Hangzhou, China.

ABSTRACT
The enzymatic synthesis of 1,3-dioleoyl-2-palmitoylglycerol (OPO), one of the main components of human milk fats, has been hindered by the relatively high cost of sn-1,3-specific lipases and the deficiency in biocatalyst stability. The sn-1,3-specific lipase from Aspergillus oryzae (AOL) is highly and efficiently immobilized with the polystyrene-based hydrophobic resin D3520, with a significant 49.54-fold increase in specific lipase activity compared with the AOL powder in catalyzing the synthesis of OPO through the acidolysis between palm stearin and oleic acid (OA). The optimal immobilization conditions were investigated, including time course, initial protein concentration and solution pH. The sn-1,3 specificity of lipases under different immobilization conditions was evaluated and identified as positively associated with the lipase activity, and the pH of the immobilization solution influenced the regiospecificity and synthetic activity of these lipases. Immobilized AOL D3520, as the biocatalyst, was used for the enzymatic synthesis of the structured lipid OPO through the acidolysis between palm stearin and OA. The following conditions were optimized for the synthesis of structured lipid OPO: 65 °C temperature; 1:8 substrate molar ratio between palm stearin and OA; 8% (w/w) enzyme load; 3.5% water content of the immobilized lipase; and 1 h reaction time. Under these conditions, highly efficient C52 production (45.65%) was achieved, with a tripalmitin content of 2.75% and a sn-2 palmitic acid (PA) proportion of 55.08% in the system.

No MeSH data available.


Related in: MedlinePlus

Carrier screening for immobilization of AOL: (a) Fixation level, (b) Lipase activity and specific activity of lipase in the acidolysis reaction for C52 synthesis from palm stearin and OA.
© Copyright Policy
Related In: Results  -  Collection

License
getmorefigures.php?uid=PMC4517815&req=5

pone.0133857.g001: Carrier screening for immobilization of AOL: (a) Fixation level, (b) Lipase activity and specific activity of lipase in the acidolysis reaction for C52 synthesis from palm stearin and OA.

Mentions: Lipase immobilization often contributes to the enhancement of the catalytic activity of this enzyme in nonaqueous system, and the effect of immobilization on lipase primarily depends on the method and the support material selected[16, 17]. The results of a previous report showed that the particles of 300 nm in diameter were suitable for immobilization[25]. Therefore, 7 PS-based non-polar and low polar resins and 4 ion-exchange resins of 300–1250 nm in diameter were screened for the immobilization of the sn-1,3-specific lipase AOL L03. Ethanol has been used to improve lipase immobilization on hydrophobic supports through decreasing the hydrophobicity of the inner surface of the pores and thereby increasing the access of lipase to these substances[17, 26]. All the hydrophobic supports displayed strong lipase adsorption, and the fixation levels were almost twice as high as that of the ion-exchange support (Fig 1A). D3520 had the highest fixation level (96.97%), and the DM11 was last among the hydrophobic supports (84.61%), with the smallest specific surface area (200–250 m2/g), and the fixation level of D318 (50.56%) was the highest among the ion-exchange supports. The immobilization yields are dependent on the structural and chemical characteristics of supports, and a large internal surface area is typically associated with high enzymatic activity.


Immobilization, Regiospecificity Characterization and Application of Aspergillus oryzae Lipase in the Enzymatic Synthesis of the Structured Lipid 1,3-Dioleoyl-2-Palmitoylglycerol.

Cai H, Li Y, Zhao M, Fu G, Lai J, Feng F - PLoS ONE (2015)

Carrier screening for immobilization of AOL: (a) Fixation level, (b) Lipase activity and specific activity of lipase in the acidolysis reaction for C52 synthesis from palm stearin and OA.
© Copyright Policy
Related In: Results  -  Collection

License
Show All Figures
getmorefigures.php?uid=PMC4517815&req=5

pone.0133857.g001: Carrier screening for immobilization of AOL: (a) Fixation level, (b) Lipase activity and specific activity of lipase in the acidolysis reaction for C52 synthesis from palm stearin and OA.
Mentions: Lipase immobilization often contributes to the enhancement of the catalytic activity of this enzyme in nonaqueous system, and the effect of immobilization on lipase primarily depends on the method and the support material selected[16, 17]. The results of a previous report showed that the particles of 300 nm in diameter were suitable for immobilization[25]. Therefore, 7 PS-based non-polar and low polar resins and 4 ion-exchange resins of 300–1250 nm in diameter were screened for the immobilization of the sn-1,3-specific lipase AOL L03. Ethanol has been used to improve lipase immobilization on hydrophobic supports through decreasing the hydrophobicity of the inner surface of the pores and thereby increasing the access of lipase to these substances[17, 26]. All the hydrophobic supports displayed strong lipase adsorption, and the fixation levels were almost twice as high as that of the ion-exchange support (Fig 1A). D3520 had the highest fixation level (96.97%), and the DM11 was last among the hydrophobic supports (84.61%), with the smallest specific surface area (200–250 m2/g), and the fixation level of D318 (50.56%) was the highest among the ion-exchange supports. The immobilization yields are dependent on the structural and chemical characteristics of supports, and a large internal surface area is typically associated with high enzymatic activity.

Bottom Line: The enzymatic synthesis of 1,3-dioleoyl-2-palmitoylglycerol (OPO), one of the main components of human milk fats, has been hindered by the relatively high cost of sn-1,3-specific lipases and the deficiency in biocatalyst stability.The sn-1,3-specific lipase from Aspergillus oryzae (AOL) is highly and efficiently immobilized with the polystyrene-based hydrophobic resin D3520, with a significant 49.54-fold increase in specific lipase activity compared with the AOL powder in catalyzing the synthesis of OPO through the acidolysis between palm stearin and oleic acid (OA).Immobilized AOL D3520, as the biocatalyst, was used for the enzymatic synthesis of the structured lipid OPO through the acidolysis between palm stearin and OA.

View Article: PubMed Central - PubMed

Affiliation: College of Biosystems Engineering and Food Science, Zhejiang University, Hangzhou, China; Zhejiang Key Laboratory for Agro-Food Processing, Zhejiang University, Hangzhou, China.

ABSTRACT
The enzymatic synthesis of 1,3-dioleoyl-2-palmitoylglycerol (OPO), one of the main components of human milk fats, has been hindered by the relatively high cost of sn-1,3-specific lipases and the deficiency in biocatalyst stability. The sn-1,3-specific lipase from Aspergillus oryzae (AOL) is highly and efficiently immobilized with the polystyrene-based hydrophobic resin D3520, with a significant 49.54-fold increase in specific lipase activity compared with the AOL powder in catalyzing the synthesis of OPO through the acidolysis between palm stearin and oleic acid (OA). The optimal immobilization conditions were investigated, including time course, initial protein concentration and solution pH. The sn-1,3 specificity of lipases under different immobilization conditions was evaluated and identified as positively associated with the lipase activity, and the pH of the immobilization solution influenced the regiospecificity and synthetic activity of these lipases. Immobilized AOL D3520, as the biocatalyst, was used for the enzymatic synthesis of the structured lipid OPO through the acidolysis between palm stearin and OA. The following conditions were optimized for the synthesis of structured lipid OPO: 65 °C temperature; 1:8 substrate molar ratio between palm stearin and OA; 8% (w/w) enzyme load; 3.5% water content of the immobilized lipase; and 1 h reaction time. Under these conditions, highly efficient C52 production (45.65%) was achieved, with a tripalmitin content of 2.75% and a sn-2 palmitic acid (PA) proportion of 55.08% in the system.

No MeSH data available.


Related in: MedlinePlus