本文選題：氣單胞菌 + 重金屬銅離子　； 參考：《西南交通大學(xué)》2017年碩士論文

【摘要】：隨著工業(yè)化快速發(fā)展及城鎮(zhèn)現(xiàn)代化進(jìn)程加快,我國(guó)所面臨的重金屬污染問(wèn)題十分嚴(yán)峻,目前我國(guó)有將近92%以上的水體受到重金屬污染,重金屬的超標(biāo)現(xiàn)象與日俱增。本文利用課題組前期從天然氣鉆井井場(chǎng)周邊污泥和鉆井廢水中篩選得到的檸檬酸桿菌、叢毛單胞菌、芽孢桿菌、氣單胞菌共4株菌株,使用單一菌或兩兩組合成復(fù)合菌群對(duì)重金屬銅模擬廢水進(jìn)行處理,使用原子吸收分光光度法測(cè)定處理前后Cu~(2+)濃度,篩選得到重金屬銅吸附優(yōu)勢(shì)菌株為氣單胞菌。采用分光光度計(jì)法測(cè)定氣單胞菌的耐受性,選擇處于對(duì)數(shù)期的氣單胞菌菌體接種到含有不同濃度的Cu~(2+)培養(yǎng)基中,每隔3h測(cè)定OD600的值,實(shí)驗(yàn)結(jié)果表明:氣單胞菌對(duì)重金屬Cu~(2+)的耐受閾值為200mg/L。采用單因素分析法研究氣單胞菌吸附重金屬銅的吸附行為,確定最優(yōu)吸附條件為:溫度30℃、pH為4、轉(zhuǎn)速為170rpm、菌體投加量為20g/L、初始Cu~(2+)濃度為100mg/L,吸附時(shí)間90min,此時(shí)吸附率86.25%。進(jìn)行Cu~(2+)的脅迫實(shí)驗(yàn),在Cu~(2+)脅迫下,氣單胞菌菌體內(nèi)的丙二醛(MDA)含量迅速增加,對(duì)氣單胞菌造成明顯的氧化損傷,同時(shí),培養(yǎng)后期MDA趨于穩(wěn)定,這一現(xiàn)象推測(cè)原因?yàn)闅鈫伟谏L(zhǎng)代謝達(dá)到穩(wěn)定后,存在于細(xì)胞膜上的酶能有效的清理體內(nèi)多余的自由基,防止繼續(xù)對(duì)細(xì)胞產(chǎn)生損害。氣單胞菌胞外聚合物中存在可以絡(luò)合Cu~(2+)的分泌物,能使菌體對(duì)Cu~(2+)的吸附效率提高,氣單胞菌胞外絡(luò)合能夠緩解Cu~(2+)對(duì)其微生物細(xì)胞體產(chǎn)生的毒性效應(yīng),從一方面說(shuō)也是其重金屬耐受性的重要機(jī)制。通過(guò)本實(shí)驗(yàn)對(duì)Cu~(2+)吸附優(yōu)勢(shì)菌株進(jìn)行篩選并分析其吸附重金屬銅離子的特性,能夠?yàn)橹亟饘巽~離子廢水的生物吸附處理技術(shù)提供理論依據(jù)。
[Abstract]:With the rapid development of industrialization and the acceleration of the modernization of cities and towns, the problem of heavy metal pollution in China is very serious. At present, more than 92% of the water bodies in China are polluted by heavy metals, and the phenomenon of heavy metals exceeding the standard is increasing day by day. In this paper, four strains of citric acid, acanthomonas, Bacillus spp and Aeromonas were screened from sludge and wastewater from natural gas drilling well site in the early stage. The heavy metal copper simulated wastewater was treated by a single bacterium or a combination of two groups of bacteria. The concentration of Cu~(2 before and after treatment was determined by atomic absorption spectrophotometry. The dominant strain of heavy metal copper adsorption was Aeromonas. The tolerance of Aeromonas was determined by spectrophotometer. The bacteria of Aeromonas in logarithmic phase were inoculated into the medium containing different concentrations of Cu~(2. The values of OD600 were measured every 3 hours. The results showed that the tolerance threshold of Aeromonas to heavy metal Cu~(2 was 200 mg / L. The adsorption behavior of heavy metal copper adsorbed by Aeromonas spp. Was studied by single factor analysis. The optimum adsorption conditions were determined as follows: temperature 30 鈩，

本文編號(hào)：1857910