Search for natural laccase mediator and its application for green chemistry

天然漆酶介体的寻找及其在绿色化学中的应用

• 批准号: 17580139
• 负责人: KAWAI Shingo
• 金额: $ 2.3万
• 依托单位: Shizuoka University
• 依托单位国家: 日本
• 项目类别: Grant-in-Aid for Scientific Research (C)
• 财政年份: 2005
• 资助国家: 日本
• 起止时间: 2005 至 2006
• 项目状态: 已结题
• 来源: https://kaken.nii.ac.jp/en/grant/KAKENHI-PROJECT-17580139/
• 关键词: Laccase; Mediator; Lignin; Anthracene; White-rot fungi; Bioremediation; バイオレメディエーション; パルプ漂白; 酸化分解

Laccase-mediator system is one of the most powerful lignin degrading systems. However, the natural laccase mediator from the culture of lignin-degrading fungi has been not reported yet. To address this question, we considered the assay systems for searching the mediator. First, we developed an assay system using the breaching abilities (brightness and Kappa number) of unbleached kraft pulp treated with laccase-mediator system. However, we rejected this system for the complicated operation. Second, we planed an assay system by using of anthracene oxidation. Laccase could only oxidized anthracene in the presence of mediator, for example 1-hydroxybenzotriazole (HBT). Consequently, this system was simple and quick assay system by using HPLC.For the mediator candidates, we prepared the ultrafiltration permeate of Trametes versicolor laccase (Fr. B) and water extracts of its fungus (Fr. F). They could act as the laccase mediator for anthracene oxidation (Degradation rate, F : 67.3%, B : 75.5 %). Then, these extracts were fractionated to hexane-soluble (Hex) and ethyl acetate-soluble (EtOAc). Three fractions of them have mediator activities (Degradation rate, F-Hex : 70.0%, B-Hex : 70.0 %, B-EtOAc : 75.6 %). The existence of mediator in these extractives is seen as a strong possibility.

漆酶-介体系统是木质素降解最强的系统之一。然而，从木质素降解真菌培养物中提取天然漆酶介体的研究尚未见报道。为了解决这个问题，我们考虑了用于搜索介体的测定系统。首先，我们开发了一个测试体系，使用漆酶-介体系统处理的未漂硫酸盐浆的破坏能力（白度和卡伯值）。但是，由于操作复杂，我们拒绝了这个系统。其次，我们设计了一个蒽氧化的检测系统。漆酶只能在介质如1-羟基苯并三唑（HBT）存在下氧化蒽。因此，该体系是一种简便、快速的高效液相色谱检测体系。它们可以作为漆酶的介体氧化蒽（降解率，F：67.3%，B：75.5%）.然后，将这些提取物分级为己烷可溶性（Hex）和乙酸乙酯可溶性（EtOAC）。其中三个级分具有介体活性（降解率，F-Hex：70.0%，B-Hex：70.0%，B-EtOAc：75.6%）。在这些萃取物中存在介体被认为是一个很大的可能性。