摘要
以一株高絮凝活性的丝状真菌菌株——糙刺篮状菌(Talaromyces sp.CC-1)为研究对象,考察了热提取法、离心沉淀法、阳离子交换树脂法、NaOH-超声法等4种方法对该菌株胞外多聚物(ECP)的提取效果,结合细胞破坏程度(核酸含量)、ECP的提取效率、化学组成分析对这4种方法进行评价.结果表明,Talaromyces sp.CC-1产生的ECP的化学组成以多糖为主,4种方法中多糖分别占ECP总量的中97%、73%、72%、67%.其中,热提取法既能提高ECP的提取效率(提取量为940 mg·L-1),又不会在提取过程中对菌株细胞造成破坏(核酸仅占ECP总量1%,为离心沉淀法、树脂法和NaOH-超声法的0.06、0.04、0.03倍),是较适宜的ECP提取方法.红外光谱(FI-IR)对热提取的ECP的进一步分析表明,ECP结构中含有较多的羧基、羟基、氨基等絮凝活性基团,凝胶渗透色谱(GPC)分析显示,ECP的分子量分布为1.7×105—3.4×106Da之间,高效液相色谱(HPLC)测定ECP的单糖组成,发现ECP中多糖主要由葡萄糖、甘露糖、木糖和半乳糖等单糖构成(物质的量之比为95.7∶5.8∶1.8∶1).
Four different ECP extraction methods, thermal extraction, centrifugal sedimentation, ion exchange resin （CER） and sodium hydroxide combined with ultrasonication, were compared on a flocculating activity filamentous fungus Talaromyces sp. CC-1. The effect was evaluated by determining the extraction efficiency, constituents of the ECP, and the extent of the cell damage （nucleic acid content）. The results show that the ECP produced by Talaromyces sp.CC-1 was mainly composed of polysaccharide, accounting for 97%, 73%, 72% and 67% of the total ECP in the four extraction methods. Thermal extraction was the most effective method for Talaromyces sp. CC- 1, based on the relatively high extraction yield （940 mg. L-1） and the comparatively small cell disruption with 1% of nucleic acid, only 0.06, 0.04 and 0.03 times of the other three. In addition, the ECP extracted by thermal extraction was confirmed to have a large molecular weight distribution （1.7× 105--3.4× 106 Da） and functional groups for flocculating by gel permeation chromatography and infrared spectroscopy. High performance liquid chromatography analyses showed that the ECP extracted by thermal extraction mainly contained glucose, mannose, xylose and galactose, with a mole ratio of 95.7：5.8：1.8：1.
出处
《环境化学》
CAS
CSCD
北大核心
2014年第4期624-629,共6页
Environmental Chemistry
基金
国家自然科学基金项目(21377057)
江苏省自然科学基金项目(BK20131313)资助
关键词
微生物絮凝剂
丝状真菌
糙刺篮状菌
胞外多聚物
提取
bioflocculant, filamentous fungi, Talaromyces sp. CC- 1, extra-cellular polymers,extraction.
作者简介
通讯联系人，Tel：13951029726；E—mail：di．fang@njau．edu．cn
