發(fā)布時間：2018-12-11 01:39

【摘要】：二甲戊樂靈(N-(1-乙基丙基)-2,6-二硝基-3,4-二甲基苯胺;CAS no.40487-42-1)是一種二硝基苯胺類除草劑。二甲戊靈的作用機制是通過二甲戊靈進(jìn)入植物體內(nèi)與微管蛋白結(jié)合,抑制植物細(xì)胞的分裂和伸長。近年來被廣泛應(yīng)用于玉米、馬鈴薯、水稻、大豆、煙草、蔬菜等多種作物的除草。它的廣泛使用導(dǎo)致在土壤、地下水、地表水和空氣中被檢測出來,對生態(tài)系統(tǒng)和人類健康產(chǎn)生了重大的危害。本實驗室從南海近海岸底泥中篩選到兩株二甲戊靈降解菌,命名為WL-4和WL-6。通過形態(tài)學(xué)、生化特征、16S r DNA序列鑒定,WL-4鑒定為假單胞菌屬(Pseudomonas sp.WL-4),WL-6鑒定為芽孢桿菌屬(Bacillus sp.WL-6)。菌株P(guān)seudomonas sp.WL-4最適p H和溫度分別是7,30℃;菌株Bacillus sp.WL-6最適p H和溫度分別是6,35℃。Haldane Andrews模型描述在不同底物濃度下,二甲戊靈的降解速率。降解速率常數(shù)qmax,Ks和Ki被擬合分別為0.02873h-1,5.629mg/L,240.2 mg/L。在菌株Bacillus sp.WL-6降解二甲戊靈過程中,通過氣相色譜質(zhì)譜聯(lián)用儀(GC-MS)有九個產(chǎn)物被捕捉和鑒定。二甲戊靈通過羥基化形成2-((3,4-二甲基-2,6-二硝基苯基)氨基)丁-1-醇再通過脫烷基形成1-(5-甲基-7-硝基-1H-苯并[d]咪唑-1-基)丙-1-酮。二甲戊靈側(cè)鏈的甲基先通過加氧酶形成羥基,然后在脫氫酶作用下生成7-氨基-5-甲基-1-(戊-3-基)-1H-苯并[d]咪唑-6-甲醛。細(xì)菌Bacillus sp.WL-6呈現(xiàn)了一個二甲戊靈全新的降解途徑。而Pseudomonas sp.WL-4有兩個產(chǎn)物被捕捉并被鑒定為為1-(5-甲基-7-硝基-1H-苯并[d]咪唑-1-基)丙-1-酮,和7-氨基-5-甲基-1-(戊-3-基)-1H-苯并[d]咪唑-6-甲醛。因此Pseudomonas sp.WL-4和Bacillus sp.WL-6可潛在用于二甲戊樂靈污染水體和土壤的生態(tài)修復(fù)。
[Abstract]:Penicillin (N- (1-ethyl propyl)-2-nitro-3-dimethylaniline; CAS no.40487-42-1) is a herbicide of dinitroaniline. The mechanism of penicillin is to inhibit the division and elongation of plant cells by entering the plant with tubulin binding. In recent years is widely used in maize, potatoes, rice, soybean, tobacco, vegetables and other crops weeding. Its widespread use has led to the detection of soil, groundwater, surface water and air, posing major risks to ecosystems and human health. Two strains of dimethopentyl degrading bacteria, named WL-4 and WL-6., were isolated from the sediments of the South China Sea near the coast in our laboratory. According to morphological and biochemical characteristics, 16s r DNA sequence, WL-4 was identified as Pseudomonas (Pseudomonas sp.WL-4) and WL-6 as Bacillus (Bacillus sp.WL-6). The optimum pH and temperature of strain Pseudomonas sp.WL-4 were 730 鈩，

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