Wojciechowska Aleksandra, Klewicki Robert, Sójka Michał, Klewicka Elżbieta
Institute of Food Technology and Analysis, Faculty of Biotechnology and Food Sciences, Lodz University of Technology, Stefanowskiego 4/10, PL-90-924 Łódź, Poland.
Institute of Fermentation Technology and Microbiology, Faculty of Biotechnology and Food Sciences, Lodz University of Technology, Wólczańska 171/173, PL-90-924 Łódź, Poland.
Food Technol Biotechnol. 2017 Jun;55(2):258-265. doi: 10.17113/ftb.55.02.17.4732.
Bionic acids are bioactive compounds demonstrating numerous interesting properties. They are widely produced by chemical or enzymatic oxidation of disaccharides. This paper focuses on the galactosyl derivative of gluconic acid as a result of a new method of bionic acid synthesis which utilises the transglycosylation properties of β-galactosidase and introduces lactose as a substrate. Products obtained in such a process are characterised by different structures (and, potentially, properties) than those resulting from traditional oxidation of disaccharides. The aim of this study is to determine the effect of selected parameters (concentration and ratio of substrates, dose of the enzyme, time, pH, presence of salts) on the course of the reaction carried out with the enzymatic preparation Lactozym, containing β-galactosidase from . Research has shown that increased dry matter content in the baseline solution (up to 50%, by mass per volume) and an addition of NaCl contribute to higher yield. On the other hand, reduced content of the derivative is a result of increased pH from 7.0 to 9.0 and an addition of magnesium and manganese salts. Moreover, exceeding the β-galactosidase dose over approx. 35 000 U per 100 g of lactose also leads to reduced yield of the process. The most favourable molar ratio of sodium gluconate to lactose is 2.225:0.675. Depending on the conditions of the synthesis, the product concentration ranged between 17.3 and 118.3 g/L of the reaction mixture, which corresponded to the mass fraction of 6.64-23.7% of dry matter. The data obtained as a result of the present study may be useful for designing an industrial process.
仿生酸是具有众多有趣特性的生物活性化合物。它们通过二糖的化学或酶促氧化广泛产生。本文重点研究葡萄糖酸的半乳糖基衍生物，这是一种利用β - 半乳糖苷酶的转糖基化特性并引入乳糖作为底物的新型仿生酸合成方法的产物。与传统二糖氧化产生的产物相比，该过程中获得的产物具有不同的结构（以及潜在的性质）。本研究的目的是确定所选参数（底物浓度和比例、酶剂量、时间、pH值、盐的存在）对使用含有来自[具体来源未提及]的β - 半乳糖苷酶的酶制剂Lactozym进行的反应过程的影响。研究表明，基线溶液中干物质含量增加（高达50%，质量/体积）以及添加NaCl有助于提高产率。另一方面，pH值从7.0增加到9.0以及添加镁盐和锰盐会导致衍生物含量降低。此外，每100克乳糖的β - 半乳糖苷酶剂量超过约35000 U也会导致该过程的产率降低。葡萄糖酸钠与乳糖最有利的摩尔比为2.225:0.675。根据合成条件，产物浓度在反应混合物的17.3至118.3 g/L之间，这对应于干物质质量分数为6.64 - 23.7%。本研究获得的数据可能对设计工业过程有用。
