Department of Chemical Engineering and Food Engineering, Federal University of Santa Catarina, P.O. Box 476, Florianopolis, SC, 88040-900, Brazil.
Bioprocess Biosyst Eng. 2019 Feb;42(2):213-222. doi: 10.1007/s00449-018-2026-9. Epub 2018 Oct 26.
The use of green sources for materials synthesis has gained popularity in recent years. This work investigated the immobilization of lipase NS-40116 (Thermomyces lanuginosus lipase) in polyurethane foam (PUF) using a biopolyol obtained through the enzymatic glycerolysis between castor oil and glycerol, catalyzed by the commercial lipase Novozym 435 for the PUF formation. The reaction was performed to obtain biopolyol resulting in the conversion of 64% in mono- and diacylglycerol, promoting the efficient use of the reaction product as biopolyol to obtain polyurethane foam. The enzymatic derivative with immobilized lipase NS-40116 presented apparent density of 0.19 ± 0.03 g/cm and an immobilization yield was 94 ± 4%. Free and immobilized lipase NS-40116 were characterized in different solvents (methanol, ethanol, and propanol), temperatures (20, 40, 60 and 80 °C), pH (3, 5, 7, 9 and 11) and presence of ions Na, Mg, and Ca. The support provided higher stability to the enzyme, mainly when subjected to acid pH (free lipase lost 80% of relative activity after 360 h of contact, when the enzymatic derivative lost around 22%) and high-temperature free lipase lost 50% of relative activity, while the immobilized remained 95%. The enzymatic derivative was also used for esterification reactions and conversions around 66% in fatty acid methyl esters, using abdominal chicken fat as feedstock, were obtained in the first use, maintaining this high conversion until the fourth reuse, proving that the support obtained using environmentally friendly techniques is applicable.
近年来，使用绿色原料合成材料已经变得越来越流行。本工作研究了通过酶促蓖麻油与甘油之间的甘油解反应，用商业脂肪酶 Novozym 435 催化生成的生物多元醇，将脂肪酶 NS-40116（Thermomyces lanuginosus 脂肪酶）固定在聚氨酯泡沫（PUF）中的方法。该反应是为了获得生物多元醇，从而使单甘酯和二甘酯的转化率达到 64%，促进反应产物作为生物多元醇的有效利用，以获得聚氨酯泡沫。用固定化脂肪酶 NS-40116 的酶衍生物的表观密度为 0.19±0.03 g/cm3，固定化产率为 94±4%。游离和固定化的 NS-40116 脂肪酶在不同溶剂（甲醇、乙醇和丙醇）、温度（20、40、60 和 80°C）、pH（3、5、7、9 和 11）和存在离子 Na、Mg 和 Ca 时的特性进行了研究。该载体为酶提供了更高的稳定性，特别是在酸性 pH（游离脂肪酶在接触 360 小时后相对活性损失了 80%，而酶衍生物损失了约 22%）和高温下，游离脂肪酶的相对活性损失了 50%，而固定化脂肪酶的相对活性保持在 95%。该酶衍生物还用于酯化反应，使用腹部鸡脂作为原料，首次反应获得了约 66%的脂肪酸甲酯转化率，在第四次重复使用时仍保持高转化率，证明了使用环保技术获得的载体是适用的。
