太湖蘆葦根系中溶藻菌的分離鑒定及溶藻效果

沈紅池+潘瑞松+吳旭鵬+蔡慶慶+張文藝

摘 要：富含氮、磷、鉀等營(yíng)養(yǎng)物質(zhì)的污水排入河流、湖泊，造成藍(lán)藻爆發(fā)，而溶藻菌可以有效降解水體中的藍(lán)藻污染。從藍(lán)藻污染嚴(yán)重的太湖百瀆港岸邊蘆葦根系中篩選出1株溶藻菌（Bacillus sp），命名為G6，系統(tǒng)發(fā)育分析表明，G6菌株與芽孢桿菌同源性最高。將培養(yǎng)至對(duì)數(shù)期的G6菌液以菌藻比1∶10的比例，在溫度28 ℃、光強(qiáng)2 500 lx、光暗比12 h∶12 h的條件下經(jīng)光照培養(yǎng)箱培養(yǎng)7 d，對(duì)銅綠囊藻液Chla去除率可達(dá)82%。此外，G6菌株在無(wú)光照條件下也具有溶藻特性，這有利于其在缺少光照的深水域中增殖并發(fā)揮溶藻作用。G6通過(guò)分泌溶藻物質(zhì)殺滅銅綠囊藻，屬于間接溶藻，且溶藻物質(zhì)具有熱穩(wěn)定性，能夠在較高溫度下發(fā)揮溶藻特性。

關(guān)鍵詞：溶藻菌；銅綠微囊藻；16SrDNA；溶藻效果

中圖分類號(hào)：X703

文獻(xiàn)標(biāo)志碼：A 文章編號(hào)：1674-4764（2017）05-0123-06

Abstract： Large amounts of sewage with nitrogen， phosphorus， potassium and other nutrients into the river lake will cause the algae bloom. Algae-lysing bacteria which can effectively degrade cyanobacteria in water is a potential treatment. An algicidal bacterium against toxic Microcystis aeruginosastrain G6 is isolated from reed roots in Baidu port of Taihu Lake. According to phylogenetic analysis， strain G6（Bacillus sp） is identified as Bacillus sp .The strain G6 which cultivated to the logarithmic phase is voted to water with bacteria and algae ratio of 1∶10. The Chl-a of algae fluid could be reduced up to 82% when it is placed in the light incubator of 28 ℃ temperature， light intensity 2 500 lux， and photoperiod 12 h∶12 h for 7 days. Strain G6 has the character that it can kill the algae cells without light. It is conducive to bacteria breeding and degradate algae in the deep sea which lack of light. The strain G6 could produce substance which can dissolv algae to kill microcystis aeruginosa， which is an indirect way to kill algae. The substance has thermal stability to kill the algae cells at high temperature.

Keywords：algicidal bacteira； microcystis aeruginosa； 16SrDNA； algicidal effect

隨著工農(nóng)業(yè)發(fā)展，富含氮、磷、鉀等營(yíng)養(yǎng)物質(zhì)的污水逐漸排入河流、湖泊中，造成水體富營(yíng)養(yǎng)化日益加劇，藍(lán)藻大規(guī)模爆發(fā)，水資源越發(fā)緊缺，水生物的生存環(huán)境受到威脅[1-3]。藍(lán)藻的死亡不僅會(huì)產(chǎn)生惡臭，其分泌的藻毒素還具有致癌性，嚴(yán)重威脅著飲用水安全和人類的身體健康[4-6]。

除藻的方法主要有物理、化學(xué)和生物方法[7]。物理法有機(jī)械除藻、直接過(guò)濾法、超聲法等[8]，但這些方法都存在著成本高，耗時(shí)長(zhǎng)的缺點(diǎn)。化學(xué)法主要通過(guò)投加化學(xué)試劑來(lái)進(jìn)行殺藻，殘留的化學(xué)藥劑仍然滯留在水體中容易造成二次污染[9-10]。所以，物理和化學(xué)方法都不能從根本上解決藍(lán)藻污染問(wèn)題。……