氯過氧化物酶與苯酚降解菌株的協(xié)同降解動力學(xué)研究

, , , , , 張永

(上海師范大學(xué) 生命與環(huán)境科學(xué)學(xué)院,上海 200234)

氯過氧化物酶與苯酚降解菌株的協(xié)同降解動力學(xué)研究

張 瑩,楚啟玉,陳淼,陳軍,肖明,張永明

(上海師范大學(xué) 生命與環(huán)境科學(xué)學(xué)院,上海200234)

氯過氧化物酶(CPO)催化苯酚與H2O2發(fā)生過氧化反應(yīng)生成鄰苯二酚,能減輕苯酚對降解菌株的抑制作用,加快降解菌株對苯酚的生物降解.實驗結(jié)果表明:在2h內(nèi)適量的H2O2存在時10U/L的CPO可以使300mg/L苯酚降解率達(dá)到67.85%,而CPO與降解菌株協(xié)同作用下苯酚降解率則可達(dá)到70.72%,比單一菌株降解率8.52%提高了62.2%.在降解體系中補充鄰苯二酚進(jìn)一步揭示了CPO氧化苯酚的中間產(chǎn)物有利于菌體細(xì)胞形成共基質(zhì)效應(yīng),提高細(xì)胞的苯酚生物降解效率.降解動力學(xué)分析顯示:在苯酚質(zhì)量濃度為100～1200mg/L時,CPO與菌株協(xié)同降解體系的最大比降解速率qmax=0.000195h-1,基質(zhì)飽和常數(shù)Ks=1.0501mg/L,基質(zhì)抑制常數(shù)KI=5.1272mg/L.

氯過氧化物酶; 過氧化作用; 協(xié)同生物降解; 苯酚殘留; 降解動力學(xué)

0 引 言

苯酚是許多化工廢水的主要污染成分[1-4],苯酚結(jié)構(gòu)中羥基化學(xué)性質(zhì)活潑,苯環(huán)結(jié)構(gòu)穩(wěn)定,因此即使在低劑量污染的狀態(tài)下,苯酚也會快速與蛋白質(zhì)等生物活性物質(zhì)發(fā)生反應(yīng),同時還會通過食物鏈的富集效應(yīng)在生物體中積累,對生物體產(chǎn)生毒害作用[5-6].生物降解苯酚是解除苯酚污染的主要手段,目前對苯酚生物降解的研究多集中在高效降解菌株的篩選和選育等方面[7-10].由于微生物通常需要幾小時甚至幾十小時的延滯期才能在細(xì)胞內(nèi)合成降解苯酚的酶系,對苯酚污染的生物危害解除速度慢,而且高濃度苯酚也會對降解菌株的生長產(chǎn)生明顯的抑制作用[11],影響了生物降解苯酚的效率.

有報道研究了過氧化酶對苯酚、氟酚等芳香族化合物的氧化作用[12-17],其中以辣根過氧化物酶(Horseradish Peroxidase,HRP)的研究最多[18].近年來,氯過氧化物酶(Chloroperoxidase,EC1.11.1.10,CPO)被用于染料氧化脫色[19-20]、芳烴氯化或脫氯[21-22]等方面的研究,具有良好的應(yīng)用效果.CPO是一種含有高鐵(IX)原卟啉為輔基的血紅素糖蛋白[24],其結(jié)構(gòu)的多重性賦予了CPO具有廣泛的底物適應(yīng)性,可以催化鹵素離子、芳香族化合物、脂肪族化合物和醇類化合物等進(jìn)行過氧化反應(yīng)[25-26].已有的研究顯示CPO可以更加快捷地鈍化芳烴物質(zhì)化學(xué)活潑性,有利于提高微生物對芳烴的可生化性能,對芳烴污染環(huán)境的生態(tài)修復(fù)具有重要的作用[27-29].本研究運用CPO與苯酚降解菌混合處理苯酚廢水,探討CPO與微生物菌株協(xié)同降解苯酚的特征,建立一種快速減少苯酚污染的生物毒性,提高苯酚降解速率的復(fù)合降解途徑.

1 材料與方法

1.1培養(yǎng)基及化學(xué)試劑

無機鹽培養(yǎng)基(MSM):Na2HPO46 g/L,KH2PO43 g/L,NaCl 0.5 g/L,NH4Cl 1 g/L,FeSO40.025 g/L,酵母膏0.2 g/L,MgSO40.24 g/L,CaCl20.011 g/L,pH=6.5～6.8,按實驗需要量加入相應(yīng)濃度的葡萄糖或苯酚,0.1 MPa,20 min滅菌.

1,1-二甲基-4-氯3,5-環(huán)己二酮(MCD)購于Sigma公司,MCD溶于含有20 mmol/L KCl的物質(zhì)的量濃度為0.1 mol/L的磷酸鉀緩沖溶液中,配制成物質(zhì)的量濃度為0.1 mmol/L的MCD溶液.

過氧化氫溶液:物質(zhì)的量濃度為10 mmol/L的過氧化氫每周配制新鮮溶液并在4℃下保存于棕色瓶中.

鄰苯二酚等試劑購于上海國藥有限公司.

1.2CPO及苯酚降解菌株

CPO利用海洋真菌(Caldariomycesfumago)發(fā)酵生產(chǎn)[30],發(fā)酵液經(jīng)過純化至酶濃度為6 146.24 U/mL,蛋白質(zhì)質(zhì)量濃度為24.35 mg/mL,RZ=A403 nm/A280 nm=1.12.其中,A403 nm是此酶含鐵卟啉結(jié)構(gòu)在403 nm波長下的特定吸光度;A280 nm是蛋白質(zhì)分子的特定吸光度,Rz為該酶純度的量值.

苯酚降解菌株分離于上海龍華污水處理場厭氧/好氧(A/O)處理池的活性污泥,經(jīng)鑒定為Micrococcuscalcoaceticus[31].

1.3實驗方法

1.3.1 CPO活力及基質(zhì)含量測定

CPO活力單位定義及測定方法參照[32].

苯酚含量測定使用Agilent 1260系列HPLC檢測,檢測條件:柱溫25 ℃,柱型號C18 4.6 mm×250 mm,恒流1.0 mL/min洗脫,檢測器:紫外檢測波長:280 nm,流動相:VA(甲醇)∶VB(體積分?jǐn)?shù)為10%的36%乙酸水溶液)=77∶23.

化學(xué)需氧量(COD)的測定采用重鉻酸鉀比色法[31].

1.3.2 苯酚生物降解實驗

經(jīng)過活化的苯酚降解菌株Micrococcuscalcoaceticus接入添加了質(zhì)量濃度為500 mg/L的葡萄糖的MSM培養(yǎng)基中,添加50 mL培養(yǎng)液入三角瓶(容量為250 mL),30 ℃,200 r/min培養(yǎng)24 h后,在10 ℃,10 000 r/min高速冷凍離心10 min,用MSM懸浮離心兩次制取細(xì)胞懸浮液,并在無碳MSM中30 ℃,180 r/min下培養(yǎng)12 h使菌體細(xì)胞處于碳饑餓狀態(tài),以MSM調(diào)節(jié)菌懸液濃度至OD600值為1.0作為降解實驗接種菌液.

CPO對苯酚轉(zhuǎn)化實驗在苯酚質(zhì)量濃度為100～1 200 mg/L的MSM中,加入最終質(zhì)量濃度為5 mg/L的H2O2,再加入一定活力濃度的CPO制備液.

菌株苯酚降解實驗分別在MSM中添加質(zhì)量濃度為100～1 200 mg/L的苯酚,接種2 mL菌液.

協(xié)同降解實驗為CPO與菌株在苯酚質(zhì)量濃度為100～1 200 mg/L的MSM中同時加入最終濃度為5 mg/L的H2O2,不同活力濃度的CPO和2 mL菌液的情況下進(jìn)行.以MSM只加5 mg/L的H2O2,不加入CPO和菌液的含相應(yīng)苯酚濃度的MSM為空白對照.降解反應(yīng)在30 ℃,150 r/min振蕩條件下完成.間隔一定時間測定降解液中苯酚濃度.以上實驗均設(shè)置3組平行重復(fù).

1.3.3 苯酚協(xié)同生物降解動力學(xué)特征描述

通過實驗描述CPO對苯酚的單獨或與苯酚降解菌協(xié)同降解苯酚的特征,分析CPO對不同初始質(zhì)量濃度S0(mg/L)的苯酚降解特性,考察在CPO與降解菌共同降解苯酚的比降解速率q(h-1),選擇合適的降解動力學(xué)模型,求找實驗條件下不同苯酚濃度下的最大比降解速率qmax(h-1),基質(zhì)飽和常數(shù)Ks(mg/L)以及基質(zhì)抑制常數(shù)KI(mg/L).以上實驗均設(shè)置3組平行重復(fù).

2 結(jié)果與討論

2.1CPO對苯酚降解的影響

圖1 CPO對苯酚的生物降解曲線

單獨添加最終濃度0、4、8、10和12 U/L的CPO,同時加入5 mg/L的H2O2,苯酚初始質(zhì)量濃度為300 mg/L,實驗條件下酶解苯酚16 h,考察苯酚初始濃度S0不變,改變CPO濃度E0對苯酚反應(yīng)速率的影響,考察CPO轉(zhuǎn)化反應(yīng)中最適酶濃度對苯酚轉(zhuǎn)化的影響,結(jié)果如圖1所示.

CPO在2 h內(nèi)對300 mg/L苯酚具有穩(wěn)定的苯酚轉(zhuǎn)化能力,隨著CPO濃度從0增加為12 U/L,2 h內(nèi)苯酚的降解率(S/S0)分別為7.25%、43.93%、56.62%、67.85%和69.45%.當(dāng)CPO濃度為12 U/L時,苯酚降解率比10 U/L時只微增1.6%,CPO濃度能已經(jīng)接近飽和.檢測反應(yīng)1.5 h 時10 U/mL CPO反應(yīng)液中苯酚質(zhì)量濃度為152.21 mg/L,而此時測出反應(yīng)液中鄰苯二酚的質(zhì)量濃度為145.64 mg/L,說明CPO氧化苯酚的主要產(chǎn)物為鄰苯二酚,這與Litvintsev等[33-34]觀察到的苯酚優(yōu)先轉(zhuǎn)化為鄰苯二酚的現(xiàn)象相符合.

2.2添加鄰苯二酚對苯酚降解的共基質(zhì)效應(yīng)

分別在兩種情況下比較菌株協(xié)同降解苯酚的特征.第一組:苯酚質(zhì)量濃度為300 mg/L時不添加或添加10 U/mL的CPO;第二組:苯酚質(zhì)量濃度為150 mg/L時不添加或添加150 mg/L鄰苯二酚,考察CPO氧化的中間產(chǎn)物鄰苯二酚對菌株降解苯酚的促進(jìn)作用,結(jié)果如圖2所示.

從圖2可知,苯酚初始質(zhì)量濃度為300 mg/L時添加10 U/mL的CPO,2 h內(nèi)菌株對苯酚的降解率為70.72%,16 h內(nèi)為88.31%;而單純菌株對苯酚的降解率只有8.52%(2 h)和71.63%(16 h).150 mg/L苯酚液與同時補充150 mg/L鄰苯二酚的降解液2 h苯酚降解率分別為11.79%和32.18%,16 h分別為48.36%和72.09%.說明添加CPO確實能提高苯酚的初期降解率,能有效降低苯酚對菌體細(xì)胞的抑制作用,經(jīng)CPO轉(zhuǎn)化后的苯酚液更加有利于菌株對苯酚的降解;補加鄰苯二酚也可以明顯促進(jìn)苯酚的生物降解.其機制可能為CPO轉(zhuǎn)化了苯酚形成更容易降解的鄰苯二酚中間產(chǎn)物,與苯酚形成共基質(zhì)效應(yīng)從而提高苯酚的生物降解效率.

圖2 菌株的苯酚降解曲線

2.3CPO與降解菌株協(xié)同降解苯酚的性能

圖3 CPO與降解菌株對苯酚的協(xié)同降解特征

以質(zhì)量濃度分別為100、300、500、700、1 000和1 200 mg/L的苯酚液為轉(zhuǎn)化對象,添加10 U/mL 的CPO,5 mg/L的H2O2,接種2 mL菌液,相同反應(yīng)條件下降解20 h,苯酚轉(zhuǎn)化結(jié)果如圖3所示.

從圖3可知,CPO和苯酚降解菌株組成的苯酚生物協(xié)同降解體系對初始質(zhì)量濃度較低(<300 mg/L)的苯酚液,2 h內(nèi)苯酚降解率高于對初始質(zhì)量濃度較高(>1 000 mg/L)的苯酚液的降解率,隨著苯酚初始濃度的提高其生物降解速度呈下降趨勢.這與高濃度苯酚對酶活性或細(xì)胞生長的抑制有關(guān)[35-36].

圖4 不同初始濃度的苯酚協(xié)同降解過程COD去除率

圖4為不同初始苯酚濃度的反應(yīng)液中COD的去除率測定結(jié)果,反應(yīng)初期(2 h內(nèi))苯酚的COD去除率差異不大,3 h后去除率快速上升,至6 h時COD的去除率與苯酚的降解率表現(xiàn)為正相關(guān),反映出苯酚經(jīng)過CPO的轉(zhuǎn)化其可生化能力得到了明顯提高,苯酚結(jié)構(gòu)被徹底分解.

2.4苯酚協(xié)同降解動力學(xué)特征

在實驗條件下探討苯酚降解的動力學(xué)特征,結(jié)果如圖5所示.圖5中直線方程的回歸系數(shù)R2均大于0.95,數(shù)據(jù)具有良好的回歸性.直線斜率為比降解速率(q),可知初始苯酚質(zhì)量濃度為100、300、500、700、1 000和1 200 mg/L時,CPO和苯酚降解菌協(xié)同降解苯酚的比降解速率分別為:0.6899、0.5429、0.3593、0.2661、0.1038和0.0604 h-1.

2.5降解動力學(xué)模型擬合

苯酚的生物降解過程存在基質(zhì)對酶和細(xì)胞的生物抑制作用可以用Haldan 模型[36]描述:

圖5 不同初始濃度的苯酚協(xié)同降解過程的比降解速率

得到二次方程:

圖6 降解動力學(xué)特征曲線

二次項趨勢線如圖6所示,R2=0.9617,實驗曲線具有較好的擬合性,分別計算出CPO與降解菌協(xié)同降解苯酚時的最大比降解速率qmax=0.000195 h-1,基質(zhì)飽和常數(shù)Ks=1.0501 mg/L,基質(zhì)抑制常數(shù)KI=5.1272 mg/L.參數(shù)表明CPO與降解菌共同構(gòu)成的協(xié)同降解苯酚體系具有高降解率,低基質(zhì)飽和度和高基質(zhì)濃度抑制的特點.

3 結(jié) 論

實驗所用的苯酚降解菌株Micrococcuscalcoaceticus是一株以鄰苯酚二酚2,3加氧酶開環(huán)的細(xì)菌[36],菌株獨自降解苯酚時先是在胞內(nèi)苯酚羥化酶催化下形成鄰苯酚二酚,再在鄰苯酚二酚2,3-加氧酶作用下生成2-羥基粘糠酸半醛,經(jīng)過進(jìn)一步代謝最后進(jìn)入三羧酸循環(huán)途徑徹底氧化成二氧化碳和水[37].CPO催化苯酚與H2O2發(fā)生過氧化反應(yīng)生成了鄰苯二酚,易氧化降解的鄰苯二酚與苯酚形成共基質(zhì)效應(yīng)加快了對苯酚的生物降解作用,減輕苯酚對降解菌株的抑制作用.因此,CPO與降解菌株協(xié)同反應(yīng)時苯酚降解率比單一菌株降解率明顯提高.實驗在較廣泛的苯酚濃度范圍內(nèi)探討了CPO與菌株構(gòu)成的苯酚協(xié)同降解體系的特征,結(jié)果表明該復(fù)合降解體系對苯酚的比降解速率高,基質(zhì)飽和常數(shù)低,基質(zhì)抑制常數(shù)高.研究結(jié)果對污染水體中苯酚類有害物質(zhì)的快速轉(zhuǎn)化和高效降解建立了一種新型模式,并在動力學(xué)機制上作出了合理解釋.

[1] Lakshmi M V V C,Sridevi V.A review on biodegradation of phenol from industry effluents [J].Journal of Industrial Pollution Control,2009,25(1):13-27.

[2] Lina S H,Juang R S.Adsorption of phenol and its derivatives from water using synthetic resins and low-cost natural adsorbents:A review [J].Journal of Environmental Management,2009,90(3):1336-1349.

[3] Mohan S V,Prasad K K,Rao N C,et al.Acid azo dye degradation by free and immobilized horseradish peroxidase (HRP) catalyzed process [J].Chemosphere,2005,58(8):1097-1105.

[4] Wu Y,Taylor K E,Biswas N,et al.Kinetic model for removal of phenol by horseradish peroxidase with PEG [J].Journal of Environmental Engineering,1999,125(5):451-458.

[5] Busca G,Berardinelli S,Resimi C,et al.Technologies for the removal of phenol from fluid streams:a short review of recent deveopments [J].Journal of Hazardous Materials,2008,160(2):265-288.

[6] Zhang Q,Cheng X D,Chen Z,et al.Roles of manganese oxides in degradation of phenol under UV-Vis irradiation:Adsorption,oxidation,and photocatalysis [J].Journal of Environmental Sciences,2011,23(11):1904-1910.

[7] Kowalska M,Bodzek M,Bohdziewicz J.Biodegradation of phenols and cyanides using membranes with immobilized microorganisms [J].Process Biochemistry,1998,33(2):189-197.

[8] Khokhawala I M,Gogate P R.Degradation of phenol using a combination of ultrasonic and UV irradiations at pilot scale operation [J].Ultrasonics Sonochemistry,2010,17(5):833-838.

[9] Li J M,Jin Z X,Yu B B.Isolation and characterization of aniline degradation slightly halophilic bacterium,Erwiniasp.strain HSA6 [J].Microbiological Research,2010,165(5):418-426.

[10] Bastos A E,Moon D H,Rossi A,et al.Salt-tolerant phenol degrading microorganisms isolated from Amazonian soil sampies [J].Arch Mircobwl,2000,174(5):346-352.

[11] Klibanov A M,Alberti B N,Morris E D.Enzymatic removal of toxic phenols and anilines from waste waters [J].Journal of Applied Biochemistry,1980,2(5):414-421.

[12] Samokyszyn V M,Freeman J P,Maddipatig K R.Peroxidase-catalyzed oxidation of penta chlorophenol [J].Chemical Research in Toxicology,1995,8(3):349-355.

[13] Nicell J A,Bewtra J K,Taylor K E.Enzyme catalyzed polymerization and precipitation of aromatic compounds from wastewater [J].Water Science and Technology,1992(3):157-164.

[14] Nicell J A,Saadi K W,Buchanan I D.Phenol polymerization and precipitation by enzyme and an additive [J].Bioresource Technology,1995(1):5-16.

[15] Kazuga C,Aitken M D,Gold A.Primary product of the horseradish peroxidase-catalyzed oxidation of pentachlorophenol [J].Environmental Science and Technology,1999,33(9):1408-1412.

[16] Choi Y J,Chae H J,Kim E Y.Steady-state oxidation model by horseradish peroxidase for the estimation of the non-inactivation zone in the enzymatic removal of pentachlorophenol [J].Journal of Bioscience and Bioengineering,1999,88(4):368-373.

[17] Szatkowski L,Thompson M K,Kaminski R,et al.Oxidative dechlorination of halogenated phenols catalyzed by two distinct enzymes:Horseradish peroxidase and dehaloperoxidase [J].Archives of Biochemistry and Biophysics,2011,505(1):22-32.

[18] Zhang J,Feng M Y,Jiang Y C,et al.Efficient decolorization/degradation of aqueous azo dyes using buffered H2O2oxidation catalyzed by a dosage below ppm level of chloroperoxidase [J].Chemical Engineering Journal,2012,191(19):236-242.

[20] Vázquezduhalt R,Ayala M,Márquezrocha F J.Biocatalytic chlorination of aromatic hydrocarbons by chloroperoxidase ofCaldariomycesfumago[J].Phytochemistry,2001,58(6):929-933.

[21] Díaz-Díaz G,Blanco-López M C,Lobo-Castaón M J,Miranda-Ordieres A J.Kinetic study of the oxidative dehalogenation of 2,4,6-trichlorophenol catalyzed by chloroperoxidase [J].Journal of Molecular Catalysis B:Enzymatic,2010,66(3):332-336.

[22] Shaw P D,Hager L P.Biological chlorination VI.Chloroperoxidase:A component of the β-ketoadipate chlorinase system [J].Journal of Biological Chemistry,1961,236(6):1626-1630.

[23] Hager L P,Morris D R,Brown F S,Eberwein H.Chloroperoxidase Ⅱ-utilization of halogen anions [J].The Journal of Biological Chemistry,1966,241( 8):1769-1777.

[24] Sanfilippo C,Nicolosi G.Catalytic behavior of chloroperoxidase fromCaldariomycesfumagoin the oxidation of cyclic conjugated dienes [J].Tetrahedron:Asymm,2002,13(17):1889-1892.

[25] Hocking M B,Intihar D J.Oxidation of phenol by aqueous hydrogen peroxide catalysed by ferric ion-catechol complexes [J].Journal of Chemical Technology & Biotechnology,2010,35(7):365-381.

[26] Karakhanov E A,Filippova T Y,M artynova S A,et al.New catalytic system for selective oxidation of aromatic compounds by hydrogen peroxide [J].Catalysis Today,1998,44(1-4):189-198.

[27] Miller V P,Tschirret-Guth R A,Ortiz P R.Chloroperoxidase-catalyzed benzylic hydroxylation [J].Archives of Biochemistry and Biophysics,1995,319(2):333-340.

[28] Vande Velde F,Bakker M,Van Rantwijk F,et al.Chloroperoxidase catalyzed enantioselective oxidations in hydrophobic organic media [J].Biotechnology and Bioengineering,2001,72 (5):523-529.

[29] Aiba S,Shoda M,Nagalani M.Kinetics of product inhibition in alcohol fermentation [J].Biotechnology and Bioengineering,2000,67 (6):671-90.

[30] 孫凌燕.氯過氧化物酶的發(fā)酵條件優(yōu)化 [D].上海:上海師范大學(xué),2009.

Sun L Y.Researches on fermentation conditions for the production of Chloroperoxidase [D].Shanghai:Shanghai Normal University,2009.

[31] 許甜甜.苯酚降解菌的分離鑒定及苯酚降解的相關(guān)研究 [D].上海:上海師范大學(xué),2012.

Xu T T.Isolation and identification of phenol degrading bacteria and related studies on phenol degradation [D].Shangai:Shanghai Normal University,2009.

[32] Hager L P,Morris D R,Brown F S,et al.Chloroperoxidase II [J].The Journal of Biological Chemistry,1966,241(8):1768-1767.

[33] Litvintsev I Y,Mimic Y U,Mikhailyuk A I,et al.Kinetics and mechanism of catalytic hydroxylation of phenol by hydrogen peroxide [J].Kinetics and Catalyst,1993,34(1):76-82.

[34] Khokhawala M,Gogate P R.Degradation of phenol using a combination of ultrasonic and UV irradiations at pilot scale operation [J].Ultrasonics Sonochemistry,2010,17(5):833-838.

[35] Ho K L,Lin B,Chen Y Y.Biodegradation of phenol usingCorynebacteriumsp.DJ1 aerobic granulesl [J].Bioresource Technology,2009,100(21):5051-5055.

[36] Wang Y C,Riess R,Nemati M.Scale-up impacts on mass transfer and bioremediation of suspended naphthalene particles in bead mill bioreactors [J].Bioresource Technology,2008,99(17):8143-8150.

[37] Ali S,Lafuente R F,Cowan D A.Meta-pathway degradation of phenolics by thermophilic Bacilli [J].Enzyme and Microbial Technology,1998,23(8):462-468.

(責(zé)任編輯：顧浩然)

DynamicsofphenolsynergisticbiodegradationbyChloroperoxidaseandbacterialstrains

Zhang Ying,ChuQiyu,ChenMiao,ChenJun*,XiaoMing,ZhangYongming

(College of Life and Environmental Sciences,Shanghai Normal University,Shanghai200234,China)

Chloroperoxidase (CPO) can catalyze phenol reacting peroxide reaction generating with H2O2to catechol,which can reduce the inhibitory effect of phenol degradating generating bacterial strains.At the meantime,it can accelerate the rate of phenol's biodegradation.The results show that10U/L of CPO has67.85% conversion rate of300mg /L phenol within2h with an appropriate amount of H2O2.While the degradation rate of phenol degradation under synergy of strain and CPO is up to70.72%,increased by62.2% comparing with a single strain degradation rate (8.52%).Supplementary catechol in the reaction system can further verified that the intermediate products can be good for forming the co-substrate effect in bacteria,thereby improving the phenol degradation efficiency of biological bacterial cells.Biodegradation dynamics analysis shows that the maximum specific degradation rate of the CPO and strain synergistic.The maximum specific degradation rateqmax=0.000195h-1,the matrix saturation constant Ks=1.0501mg/L,and the substrate inhibition constant KI=5.1272mg/L when phenol concentration in the range of100～1200mg/L.

Chloroperoxidase; peroxidation; synergistic biodegradation; phenol residues; degradation dynamics

2016-04-01

國家自然科學(xué)基金 (31070671);上海市科委項目 (11440502300).

張 瑩(1992-),女,碩士研究生,主要從事微生物分子、生物學(xué)方面的研究.E-mail:18363622613@qq.com

導(dǎo)師簡介: 陳 軍(1966-),男,副教授,博士,主要從事微生物酶學(xué)方面的研究.E-mail:cj7206@shnu.edu.cn

X506

:A

:1000-5137(2017)04-0453-07

*