Hongkong Baptist University & Institute of Soil Science, Chinese Academy of Sciences, Nanjing, China.
Curr Microbiol. 2010 May;60(5):336-42. doi: 10.1007/s00284-009-9546-0. Epub 2009 Nov 19.
Biodegradation of polycyclic aromatic hydrocarbons (PAHs) by pure laccase has been reported, but the high cost limited its application in environmental bioremediation. Here, we reported a study about PAHs degradation by crude extracts (CEs) containing laccase, which were obtained by extracting four spent mushroom (Agaricus bisporus, Pleurotus eryngii, Pleurotus ostreatus, and Coprinus comatus) substrates. The results showed that anthracene, benzo[a]pyrene, and benzo[a]anthracene were top three degradable PAHs by CEs while naphthalene was most recalcitrant. The PAHs oxidation was enhanced in the presence of 2,2-azino-bis-(3-ethylbenzothiazoline-6-sulfonic acid) (ABTS). Laccase included in CE might play a major role in PAHs degradation. The maximum degradation rate of anthracene and benzo[a]pyrene was observed by using crude extracts from P. eryngii while the highest laccase activities were found in crude extracts from A. bisporus, moreover, crude extracts from P. eryngii, which contained less laccase activities, degraded more anthracene and benzo[a]pyrene than pure laccase with higher laccase activities. The lack of correlation between laccase activity and PAHs degradation rate indicated that other factors might also influence the PAHs degradation. Boiled CEs were added to determine the effect on PAHs degradation by laccase. The results showed that all four boiled CEs had improved the PAHs oxidation. The maximum improvement was observed by adding CEs from P. eryngii. It suggested that some mediators indeed existed in CEs and CEs from P. eryngii contained most. As a result, CEs from P. eryngii has the most application potential in PAHs bioremediation.
已报道纯漆酶可生物降解多环芳烃（PAHs），但成本高限制了其在环境生物修复中的应用。本研究报道了从四种废弃蘑菇（双孢蘑菇、杏鲍菇、糙皮侧耳和毛头鬼伞）基质中提取含有漆酶的粗提物（CEs）对 PAHs 降解的研究。结果表明，CEs 对蒽、苯并[a]芘和苯并[a]蒽的降解能力最强，而萘最难降解。在 2,2-联氮-双（3-乙基苯并噻唑啉-6-磺酸）（ABTS）存在下，PAHs 氧化增强。CEs 中包含的漆酶可能在 PAHs 降解中起主要作用。使用杏鲍菇的粗提物观察到蒽和苯并[a]芘的最大降解率，而双孢蘑菇的粗提物具有最高的漆酶活性，此外，漆酶活性较低的杏鲍菇粗提物比具有更高漆酶活性的纯漆酶降解了更多的蒽和苯并[a]芘。漆酶活性与 PAHs 降解率之间缺乏相关性表明，其他因素也可能影响 PAHs 的降解。添加煮沸的 CEs 以确定其对漆酶降解 PAHs 的影响。结果表明，四种煮沸的 CEs 均提高了 PAHs 的氧化。添加杏鲍菇的 CEs 可获得最大的提高。这表明 CEs 中确实存在一些介体，并且杏鲍菇的 CEs 中含有最多的介体。因此，杏鲍菇的 CEs 在 PAHs 生物修复中具有最大的应用潜力。
