Bernal Claudia, Illanes Andres, Wilson Lorena
Escuela de Ingeniería Bioquímica, Pontificia Universidad Católica de Valparaíso, Avenida Brasil 2085, P.O. Box 4059, Valparaíso, Chile.
J Agric Food Chem. 2015 Apr 15;63(14):3716-24. doi: 10.1021/jf505222x. Epub 2015 Apr 1.
Sugar esters are considered as surfactants due to its amphiphilic balance that can lower the surface tension in oil/water mixtures. Enzymatic syntheses of these compounds are interesting both from economic and environmental considerations. A study was carried out to evaluate the effect of four solvents, temperature, substrate molar ratio, biocatalyst source, and immobilization methodology on the yield and specific productivity of lactulose palmitate monoester synthesis. Lipases from Pseudomonas stutzeri (PsL) and Alcaligenes sp. (AsL), immobilized in porous silica functionalized with octyl groups (adsorption immobilization, OS) and with glyoxyl-octyl groups (both adsorption and covalent immobilization, OGS), were used. The highest lactulose palmitate yields were obtained at 47 °C in acetone, for all biocatalysts, while the best lactulose:palmitic acid molar ratio differed according to the immobilization methodology, being 1:1 for AsL-OGS biocatalyst (20.7 ± 3%) and 1:3 for the others (30-50%).
由于糖酯具有两亲平衡，能够降低油/水混合物中的表面张力，因此被视为表面活性剂。从经济和环境角度考虑，这些化合物的酶促合成具有重要意义。开展了一项研究，以评估四种溶剂、温度、底物摩尔比、生物催化剂来源和固定化方法对乳糖棕榈酸单酯合成产率和比生产率的影响。使用了固定在辛基官能化多孔二氧化硅上的斯氏假单胞菌脂肪酶（PsL）和产碱杆菌脂肪酶（AsL）（吸附固定化，OS），以及固定在乙醛酸辛基官能化多孔二氧化硅上的脂肪酶（吸附和共价固定化，OGS）。对于所有生物催化剂，在47℃的丙酮中可获得最高的乳糖棕榈酸产率，而最佳的乳糖与棕榈酸摩尔比因固定化方法而异，AsL-OGS生物催化剂为1:1（20.7±3%），其他生物催化剂为1:3（30-50%）。
