本文關(guān)鍵詞：一株DBP降解菌DNB-S1的降解特性及其攝食行為的研究　出處：《東北農(nóng)業(yè)大學(xué)》2016年碩士論文　論文類型：學(xué)位論文

  更多相關(guān)文章： DBP降解菌 細(xì)菌細(xì)胞亞顯微結(jié)構(gòu) 細(xì)胞膜表面疏水性 細(xì)胞膜表面官能團(tuán) 攝食機(jī)制

【摘要】：鄰苯二甲酸二丁酯(DBP)是鄰苯二甲酸酯(PAEs)的其中一種,作為塑料中的增塑劑被廣泛應(yīng)用于生產(chǎn)生活中,DBP很容易釋放到環(huán)境中,對環(huán)境造成污染,威脅人類的生命健康。本研究以研究室前期篩選得到的DBP降解菌Novosphingobium aromaticivorans DNB-S1為研究對象,研究了DNB-S1的生長降解特性,并對其攝食行為進(jìn)行初步探索,研究得到的主要成果如下:(1)菌株DNB-S1在不同營養(yǎng)條件下的生長速率不同,生長速率由快到慢的處理為:LBMSM-GluMSM-DBP+GluMSM-DBP。菌株DNB-S1對DBP的降解效果受pH及溫度影響,在p H為7.0或溫度為35℃時(shí)降解速率最高,48 h均可降解86.4%的DBP。(2)菌株DNB-S1對DBP、DMP、DEP和DEHP均有降解效果,以MSM培養(yǎng)基培養(yǎng),在72 h內(nèi)可分別將500 mg/L的DBP、DMP、DEP和DEHP降解95%、95%、84%和60%以上。使用4種PAEs混合的MSM培養(yǎng)基培養(yǎng)菌株DNB-S1,菌株生長情況良好,5天內(nèi)對125 mg/L的DBP、DMP、DEP和DEHP的降解率可分別達(dá)到93%、88%、97%和71%以上,使500 mg/L的混合PAEs降解88%以上。(3)DNB-S1在各處理中生長狀態(tài)均良好,細(xì)胞壁平滑,細(xì)胞外膜內(nèi)膜結(jié)構(gòu)完整,無溶膜現(xiàn)象細(xì)胞質(zhì)飽滿,核糖體延細(xì)胞內(nèi)膜在細(xì)胞質(zhì)中呈均勻分布狀態(tài),擬核形態(tài)正常,沒有變異。當(dāng)培養(yǎng)體系中存在DBP的條件下,DNB-S1細(xì)胞外部的肽聚糖層消失。(4)DNB-S1可根據(jù)不同環(huán)境及不同DBP的含量調(diào)節(jié)自身CSH,以MSM-DBP培養(yǎng)基或MSM-DBP+Glu培養(yǎng)基培養(yǎng)的菌株在培養(yǎng)初期CSH高達(dá)79.8%,在3天后穩(wěn)定于50%左右;以MSM-Glu培養(yǎng)基培養(yǎng)的菌株在培養(yǎng)初期CSH為26.9%,3天后穩(wěn)定于50%左右;以LB培養(yǎng)基培養(yǎng)的菌株CSH在7天內(nèi)始終保持在9.3%-13.4%之間。培養(yǎng)的p H和溫度對菌株DNB-S1的CSH均有一定影響,菌株DNB-S1在酸性環(huán)境或溫度為30-35℃環(huán)境中CSH較高。(5)用100 mg/L的初始DBP濃度培養(yǎng)菌株72 h,整個(gè)降解體系及細(xì)胞外液中的DBP含量隨時(shí)間呈逐漸下降趨勢。而培養(yǎng)初期,菌體表面迅速積累DBP,積累量達(dá)到1.2 mg/L,之后菌體細(xì)胞表面積累的DBP含量隨培養(yǎng)時(shí)間逐漸下降,72 h后降至0.3 mg/L以下;菌體細(xì)胞內(nèi)部的DBP含量隨培養(yǎng)時(shí)間不斷增加,在48-72 h之內(nèi)基本保持穩(wěn)定狀態(tài),證明DBP能夠順利進(jìn)入到菌體細(xì)胞內(nèi)并被持續(xù)降解利用。(6)不論培養(yǎng)體系中是否存在DBP,DNB-S1親水基團(tuán)的種類都保持不變。當(dāng)培養(yǎng)體系中存在DBP時(shí),DNB-S1細(xì)胞膜表面會生成疏水性基團(tuán)C-H和R-COOH;當(dāng)培養(yǎng)體系中不存在DBP時(shí),這些疏水性基團(tuán)會相應(yīng)消失。
[Abstract]:Dibutyl phthalate (DBP) phthalate two formic acid ester (PAEs) one, as the plasticizer is widely used in production and life in plastic, DBP is easily released into the environment, causing pollution to the environment, threat to human health. This study is based on the room before the screen of the DBP Degradation Strain Novosphingobium aromaticivorans DNB-S1 as the research object, studies the growth and degradation characteristics of DNB-S1, and makes a preliminary exploration on its feeding behavior, main research results are as follows: (1) the growth rate of strain DNB-S1 in different nutrition conditions, the growth rate from fast to slow: LBMSM-GluMSM-DBP+GluMSM-DBP. strain DNB-S1 effect on DBP the degradation effect of pH and temperature in P H 7 or the temperature is 35 DEG C when the degradation rate is highest, 48 h can degrade 86.4% DBP. (2) strain DNB-S1 on DBP, DMP, DEP and DEHP have the effect of degradation, In MSM medium, within 72 h respectively 500 mg/L, DBP, DMP, DEP and DEHP was 95%, 95%, 84% and more than 60%. The use of 4 kinds of PAEs hybrid MSM medium strain DNB-S1, strain DBP, good growth, to 125 mg/L DMP in 5 days, the degradation of DEP and the rate of DEHP can reach 93%, respectively, 88%, 97% and 71% above, the above mixed PAEs degradation of 88% 500 mg/L. (3) DNB-S1 well growth state in each treatment, cell wall smooth, endometrial cell membrane structure integrity, no film dissolution phenomenon of cytoplasmic ribosomal membrane was full, extended state of uniform distribution in the cytoplasm, the nuclear morphology was normal, no mutation. When the culture conditions of DBP exist in the system, the peptidoglycan layer DNB-S1 outside of the cell disappeared. (4) DNB-S1 according to the different environment and different content of DBP regulates its own CSH, with MSM-DBP medium or MSM-DBP+Glu medium strain at the beginning of culture C SH up to 79.8%, 3 days after the stable at around 50%; cultured with MSM-Glu strain in the early culture of CSH was 26.9%, 3 days after the stable at around 50%; with LB culture medium of strain CSH in 7 days is always maintained at between 9.3%-13.4%. The cultured P H and temperature of the DNB-S1 strain of CSH influence of strain DNB-S1 in acidic environment or high temperature environment. C CSH 30-35 (5) strain 72 h 100 mg/L with the initial concentration of DBP culture, DBP content of the whole system and the degradation of extracellular fluid decreased gradually with time. And the initial cultivation, cell surface rapid accumulation of DBP, accumulation up to 1.2 mg/L, the content of DBP after cell surface accumulation decreased gradually with incubation time, after 72 h below 0.3 mg/L; the content of DBP within the bacterial cells increased with incubation time, remained stable in 48-72 within h, proved that DBP can smoothly Into the cell and was sustained by degradation. (6) no matter whether culture exists in the DBP system, DNB-S1 type of hydrophilic group will remain unchanged. When the culture exists in DBP system, DNB-S1 cell membrane surface hydrophobic groups C-H and R-COOH; when the DBP does not exist in the training system, these hydrophobic the corresponding groups will disappear.

【學(xué)位授予單位】：東北農(nóng)業(yè)大學(xué)
【學(xué)位級別】：碩士
【學(xué)位授予年份】：2016
【分類號】：X172
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本文編號：1363205