Department of Food Engineering and Technology, Institute of Chemical Technology, Nathalal Parekh Marg, Matunga, Mumbai 400 019, India.
Department of Pharmaceutical Sciences and Technology, Institute of Chemical Technology, Nathalal Parekh Marg, Matunga, Mumbai 400 019, India.
Food Chem. 2019 Mar 1;275:95-104. doi: 10.1016/j.foodchem.2018.09.090. Epub 2018 Sep 15.
This study reports on removal of acrylamide from roasted coffee by acrylamidase from Cupriavidus oxalaticus ICTDB921. Chitosan coated calcium alginate beads were functionalized with citric acid as nontoxic cross linker and activated by 1-ethyl-3-(3-dimethylaminopropyl) carbodiimide hydrochloride (EDC) and N-hydroxysuccinimide (NHS) (1.66:1 w/w) for covalent immobilization of acrylamidase. The optimum beads were obtained using 5% sodium alginate, 1.5% chitosan, and 0.6 mol/L citric acid. The beads prepared at each step were characterized by FTIR and SEM. Coating of chitosan matrix on calcium alginate beads enhanced the mechanical stability over that of calcium alginate and/or chitosan. The immobilized acrylamidase showed optimum pH/temperature of 8.5/65 °C, improved pH/thermal/shelf stability, and retained 80% activity after four cycles. Haldane model could describe the degradation kinetics of acrylamide in batch study. In packed bed column, a bed height, feed flow rate and inlet acrylamide concentration of 20 cm, 1 mL/min, and 100 mg/L gave best results.
本研究报告了利用 Oxalobacter oxalaticus ICTDB921 的丙烯酰胺酶从烤咖啡中去除丙烯酰胺。壳聚糖包覆的海藻酸钙珠用柠檬酸作为无毒交联剂进行功能化，并用 1-乙基-3-(3-二甲基氨基丙基)碳二亚胺盐酸盐 (EDC) 和 N-羟基琥珀酰亚胺 (NHS) (1.66:1 w/w) 激活，用于丙烯酰胺酶的共价固定化。使用 5%海藻酸钠、1.5%壳聚糖和 0.6 mol/L 柠檬酸可获得最佳珠粒。通过傅里叶变换红外光谱 (FTIR) 和扫描电子显微镜 (SEM) 对制备的每个步骤的珠粒进行了表征。壳聚糖基质的涂层提高了钙藻酸盐珠的机械稳定性，优于钙藻酸盐和/或壳聚糖。固定化的丙烯酰胺酶表现出最佳的 pH/温度为 8.5/65°C，提高了 pH/热/货架稳定性，并在四个循环后保留了 80%的活性。Haldane 模型可以描述批处理研究中丙烯酰胺的降解动力学。在填充床柱中，床高、进料流速和入口丙烯酰胺浓度为 20 cm、1 mL/min 和 100 mg/L 时，效果最佳。
