El Agha Ayman, Abbeddou Souheila, Makris Dimitris P, Kefalas Panagiotis
Department of Food Quality and Chemistry of Natural Products, Mediterranean Agronomic Institute of Chania, Chania, Greece.
Biodegradation. 2009 Apr;20(2):143-53. doi: 10.1007/s10532-008-9208-0. Epub 2008 Aug 1.
The exploitation of food residual sources consists of a major factor in reducing the polluting load of food industry wastes and developing novel added-value products. Plant food residues including trimmings and peels might contain a range of enzymes capable of transforming bio-organic molecules with potential phytotoxicity, including hydrolases, peroxidases and polyphenoloxidases. Although the use of bacterial and fungal enzymes has gained interest in studies pertaining to bioremediation applications, plant enzymes have been given less attention or even disregarded. In this view, this study aimed at the investigating the use of a crude peroxidase preparation from onion solid by-products for oxidising caffeic acid, a widespread o-diphenol, whose various derivatives may occur in food industry wastes, such as olive mill waste waters. Increased enzyme activity was observed at a pH value of 5, but considerable activity was also retained for pH up to 7. Favourable temperatures for increased activity varied between 20 degrees C and 40 degrees C, 30 degrees C being the optimal. Liquid chromatography-mass spectrometry analysis of a homogenate/H(2)O(2)-treated caffeic acid solution revealed the existence of a tetramer as major oxidation product. Based on the data generated, a putative pathway for the formation of the peroxidase-mediated caffeic acid tetramer was proposed.
开发食品残余资源是减少食品工业废弃物污染负荷和开发新型增值产品的一个主要因素。包括修剪物和果皮在内的植物性食品残余物可能含有一系列能够转化具有潜在植物毒性的生物有机分子的酶，包括水解酶、过氧化物酶和多酚氧化酶。尽管在生物修复应用研究中，细菌和真菌酶的使用已引起关注，但植物酶却较少受到关注甚至被忽视。有鉴于此，本研究旨在考察利用洋葱固体副产品中的粗制过氧化物酶制剂氧化咖啡酸（一种广泛存在的邻二酚）的情况，其各种衍生物可能存在于食品工业废弃物中，如橄榄果渣废水。在pH值为5时观察到酶活性增加，但在pH值高达7时也保留了相当的活性。活性增加的适宜温度在20℃至40℃之间变化，30℃为最佳温度。对匀浆/H₂O₂处理的咖啡酸溶液进行液相色谱-质谱分析，结果显示存在一种四聚体作为主要氧化产物。基于所产生的数据，提出了过氧化物酶介导的咖啡酸四聚体形成的推测途径。
