摘要
深山含笑是一种常绿乔木,具有较好的园林观赏价值,其叶片在每年春天新旧叶交替时,会陆续凋落而不能实现其经济价值;我们前期研究发现深山含笑成熟叶片具有较高的过氧化物酶活性,而过氧化物酶在内分泌干扰物生物酶法降解途径中发挥着重要作用。为充分开发深山含笑叶的经济价值,提高资源的利用效率,我们对深山含笑叶过氧化物酶进行了纯化并初步研究了其性质;在此基础上,进一步研究了深山含笑叶过氧化物酶在降解环境污染物双酚A上的特性。结果显示,经过非离子表面活性剂(吐温-80)抽提、双水相萃取、DEAE-Sepharose离子交换层析,首次从深山含笑叶片中快速分离提纯结合态过氧化物酶,相对可溶性过氧化物酶纯化倍数为55. 2倍,回收率为19%。该酶的比活力为18 999 U/mg蛋白,以愈创木酚为反应底物的最佳pH值为4. 5,最适温度为50℃;具有较宽的pH稳定范围,热稳定性较好,60℃以下不易失活。深山含笑叶过氧化物酶对BPA具有良好的清除能力,在pH4~7,温度30~40℃,H2O2/BPA摩尔浓度之比达0. 8条件下,经过3 h,10 000 U/L POD对0. 2 mmol/L BPA清除率达90%以上,深山含笑过氧化物酶在酚类物质生物酶法催化降解途径中具有潜在的重大利用价值。
Michelia maudiae Dunn is evergreen arbor species with high ornamental value.The leaves will gradually withered and can’t achieve its economic value when the old and new leaves update.It was found that the leaves of M.maudiae Dunn have the peroxidase activity in the previous studies.Regarding the compelling effect of peroxidase in process of phenols biodegradation,the purification and properties of the peroxidase from the leaves of M.maudiae Dunn were studied to fully develop the value of the leaves and to improve the resource utilization efficiency.Based on that,its function of removing bisphenol A was further investigated.The results showed that,after extracted by Tween-80,aqueous two-phase extraction,and DEAE-Sepharose Fast Flow ion-exchange chromatography,the yield of bound peroxidase purified from the leaves of M.maudiae Dunn was 19%,and purification fold compared with soluble peroxidase was 55.2 with specific activity of 18 999 U/mg.The optimal pH for the substrate of guaiacol was 4.5.The optimal temperature was 50℃.The activity of the enzyme can be maintained for a long time below 60℃(good thermal stability).M.maudiae Dunn leaves peroxidase has good scavenging ability on BPA.Under the conditions of pH4-7,30-40℃and reach the ratio of H2O2/BPA to 0.8,the clearance rate of 0.2 mmol/L BPA derivatives for 10 000 U/L M.maudiae Dunn leaves peroxidase was 90%in 3 hours later.M.maudiae Dunn leaves peroxidase had convincing future in researches of phenols biodegradation.
作者
赵广华
肖强
洪健
ZHAO Guang-hua;XIAO Qiang;HONG Jian(Hubei key Laboratory of Biological Resources Protection and utilization (Hubei University forNationalities;School of Forestry and Horticulture,Hubei University for Nationalities,Enshi 445000,China)
出处
《天然产物研究与开发》
CAS
CSCD
北大核心
2019年第2期338-344,249,共8页
Natural Product Research and Development
基金
国家自然科学基金(31260057
31460203)
关键词
过氧化物酶
纯化
双水相萃取
双酚A
深山含笑
peroxidase
purification
aqueous two-phase extraction
BPA
Michelia maudiae Dunn