978 resultados para Purinergic P1


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下载PDF阅读器2008年3月-2009年3月,把35 000尾滇池金线鲃(Sinocyclocheilus grahami)仔稚鱼分别饲养于3个池塘进行对比饲养研究.密度分别是:P1为208尾/m3;P2为167尾/m3;P3为41尾/m3.饲养期间采用相同的管理措施.每天数据收集采用:在仔鱼孵化后的5~16d的每天8:00和18:00从每个育苗池中捞取5~8尾仔鱼进行测量分析.仔鱼开口30d后,每月从培育池各捞取15尾,测量全长和体重.研究发现,滇池金线鲃仔鱼的开口时间为孵化后的5 d,混合营养期3~5d,这与初孵的演池金线鲃仔鱼的全长和卵黄囊较大有关.在容易造成仔鱼大量死亡的混合营养期,通过采用浆状物-轮虫-人工混合饲料的方式,大幅度提高了滇池金线鲃仔稚鱼的存活率,孵化一年后的滇池会线鲃稚鱼存活率可达82.7%.经过一周年的饲养,滇池金线鲃稚鱼的体重由(0.027±0.01)g(0.003~1.22)增长到(8.83±0.54)g (3.7~16.7),月均增重为0.73 g;全长由(15.8±0.30)mm (11.5~20.0)增长到(91.6±1.67)mm (75.0~16.0),全长月均增长6.32 mm.滇池金线鲃稚鱼全年全长的增长呈线性相关,y=9.82+7.05month(R2=0.9891);全年体重的增长呈指数关系,y=0.0158month2.54(R2=0.9939).

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下载PDF阅读器目的 研究三七总皂苷(Panax notoginseng saponins,PNS)对大鼠海马脑片CA1区锥体神经元兴奋性和抑制性突触传递的作用.方法 断头法分离3~4周雄性Wistar大鼠海马半脑,用切片机切出400μm厚度的海马脑片,对CA1区锥体细胞采用"盲法"全细胞膜片钳技术记录,分别检测和分析PNS(0.05~0.4 g/L)对刺激CA1传人纤维引出的兴奋性突触后电流(EPSCs)和抑制性突触后电流(IPSCs)的影响,继而以脉冲间隔为50 ms的配对刺激代替单刺激,通过EPSC2/EPSC1(P2/P1)值的变化观察PNS对双脉冲易化(paired-pulse facilitation,PPF)的影响.结果 0.1~0.4 g/L PNS显著抑制EPSCs(P<0.05),且PNS在抑制P1、P2的同时明显升高P2/P1值(P<0.05),加强了双脉冲易化,但PNS对IPSCs无显著影响(P>0.05).结论 PNS 显著减小大鼠海马CA1区锥体神经元的EPSCs而不影响IPSCs,说明PNS不是通过强化抑制性中间神经元的功能间接地抑制兴奋性神经元,而是对兴奋性突触传递直接产生抑制;PNS明显升高P2/p1值,说明 PNS是通过突触前机制抑制CA1区兴奋性突触传递.

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Data on intergroup-interactions (I-I) were collected in 5 seasonally provisioned groups (A, B, D, D-1, and E) of Tibetan macaques (Macaca Thibetana) at Mt. Emei in three 70-day periods between 1991 April-June (P1), September-November (P2), December-1992 February (P3). The I-I were categorized as forewarning made by high-ranking males (including Branch Shaking and/or Loud Calls), long-distance interactions in space (specified by changes in their foraging movements), and close encounters (with Affinitive Behavior, Male's Herding Female, Sexual Interaction, Severe Conflict, Adult Male-male Conflict, Opportunistic Advance and Retreat, etc. performed by different age-sex classes). From periods Fl to P3, the I-I rate decreased with reduction in population density as a positive correlate of food clumpedness or the number of potential feeders along a pedestrian trail. On the other hand, from the birth season (BS, represented by P1 and P3) to the mating season (MS, represented by P2) the dominance relation between groups, which produced a winner and a loser in the encounters, became obscure; the proportion of close encounters in the I-I increased; the asymmetry (local groups over intruders) of forewarning signals disappeared; the rate of branch shaking decreased; and sometimes intergroup cohesion appeared. Considering that sexual interactions also occurred between the encountering groups, above changes in intergroup behaviors may be explained with a model of the way in which the competition for food (exclusion) and the sexual attractiveness between opposite sexes were in a dynamic equilibrium among the groups, with the former outweighing the latter in the BS, and conversely in the MS. Females made 93% of severe conflicts, which occurred in 18% of close encounters. Groups fissioned in the recent past shared the same home range, and showed the highest hostility to each other by females. In conspicuous contrast with females' great interest in intergroup food/range competition, adult male-male conflicts that were normally without body contact occurred in 66% bf close encounters; high-ranking male herding of females, which is typical in baboons, appeared in 83% of close encounters, and showed no changes with season and sexual weight-dimorphism; peripheral juvenile and subadult males were the main performers of the affinitive behaviors, opportunistic advance and retreat, and guarding at the border. In brief, all males appeared to "sit on the fence" at the border, likely holding out hope of gaining the favor of females both within and outside the group. Thus, females and males attempted to maximize reproductive values in different ways, just as expected by Darwin-Trivers' theory of sexual selection. In addition, group fission was observed in the largest and highest-ranking group for two times (both in the MS) when its size increased to a certain level, and the mother group kept their dominant position in size and rank among the groups that might encounter, suggesting that fission takes a way of discarding the "superfluous part" in order to balance the cost of competition for food and mates within a group, and the benefit of cooperation to access the resources for animals in the mother group. (C) 1997 Wiley-Liss, Inc.

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利用人工湿地和养殖塘构建了复合养殖系统,通过设置不同塘间水质差异,调查了斑点叉尾鮰鱼鱼种培育段和成鱼养殖段不同梯度下的浮游动物种类丰度,并探讨了种类丰度与环境因子的关系.结果表明,2养殖阶段的循环塘中,轮虫的种类丰度随养殖密度的增加而升高,浮游甲壳动物随养殖密度的增加而降低.成鱼养殖阶段对照塘中轮虫的种类丰度高于循环塘P1、P2;枝角类和桡足类的丰度则低于P1、P2;高养殖密度塘P3中,3种形态浮游动物种类丰度均低于对照塘.15种环境因子的主成分分析以及种类丰度与环境因子的冗余度分析结果表明,影响浮游动物

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肿瘤坏死因子受体(TNFR)是细胞因子受体家族中的一员,在大DNA病毒的免疫逃避中起着重要的作用。 淋巴囊肿病毒中国株(LCDV-C)是一种大DNA病毒,属于虹彩病毒科。参照已知虹彩病毒TNFR基因设计引物: P1,5′GGATCCAAAACTATGATTAAAATAAAGA 3′;P2:5′ATTACTCGAGAATGTTAAAAATTAAGCTT 3′。以LCDV-C基因组DNA为模板,PCR扩增得到一个834bp的DNA片段,并对该片段进行测序。构建原核表 达重组质粒后,在大肠杆菌DE3中诱导表达,

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This paper presents a generalized vector control system for a generic brushless doubly fed (induction) machine (BDFM) with nested-loop type rotor. The generic BDFM consists of p1/p2 pole-pair stator windings and a nested-loop rotor with N number of loops per nest. The vector control system is derived based on the basic BDFM equation in the synchronous mode accompanied with an appropriate synchronization approach to the grid. An analysis is performed for the vector control system using the generic BDFM vector model. The analysis proves the efficacy of the proposed approach in BDFM electromagnetic torque and rotor flux control. In fact, in the proposed vector control system, the BDFM torque can be controlled very effectively promising a high-performance BDFM shaft speed control system. A closed-loop shaft speed control system is composed based on the presented vector control system whose performance is examined both in simulations and experiments. The results confirm the high performance of the proposed approach in BDFM shaft speed control as well as a very close agreement between the simulations and experiments. Tests are performed on a 180-frame prototype BDFM. © 2012 IEEE.

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利用活体观察及蛋白银染色技术对钟形钟虫的形态学及表膜下纤维系统进行了研究 ,分别给出活体及蛋白银制片后标本的鉴别特征及表膜下纤维系统。本种活体鉴定主要特征为虫体呈宽钟状 ,细胞质不透明 ,镜下明显可见有散布的脂滴存在。蛋白银制片特征为口器明显呈横位 ,第 1(P1)和第 2咽膜 (P2 )汇合后形成的短咽膜弯曲程度较甚。纵向纤维粗壮而稀疏 ,40— 5 0条 ;口围盘纤维网粗壮 ,呈轮辐状排布 ,相邻两轮辐外部末端多呈闭合态 ;第 3咽膜 (P3)由 3排毛基索组成 ,其靠近P2 侧的一列毛基索在P1与P

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聚酞亚胺(P1)的电化学活性对电路泄漏、金属腐蚀、金属与PI界面的老化有直接影响,研究聚酞亚胺的这一特性对金属防护、分子器件的设计、电沉积、材料的开发和修饰等具有潜在的应用价值。我们采用系列化学环化的可溶性PI样品,系统研究其在不同溶剂中及PI浇铸膜的电化学行为,这对进一步弄清PI这一新的电化学体系的电荷传递机理,探讨PI新的应用前景具有重要意义。本文工作获得以下几个有意义的结果(1)一般情况下,PI溶液的电化学反应是准可逆的,而且,在循环伏安图中,峰电流与电位扫速的平方根成正比,因此反应受扩散步骤控制。(2) PI的分子中的共扼结构与其电化学反应有关,因此,PI的电化学反应伴随着电致变色现象。(3)首次发现,溶剂对PI的电化学行为有很大影响,在有的溶剂中,Pl的电化学反应是准可逆的,但在有些溶剂中,却观察不到PI的电化学反应。(4)首次发现,PI的形态对其电化学性质也有很大影响,PI分子链段柔性好的有较可逆性的电化学行为。(5)可溶性聚酞亚胺在溶液中浓度越大,对其电化学反应越有利。(6) PI浇铸膜修饰电极的电化学响应在开始时随膜的厚度的增加而增大,而且稳定性也越好,当达到一定厚度后,电化学响应达到一个恒定值。(乃PI浇铸膜修饰电极在所试验的不同有机溶剂中均有较好电化学响应。 (8) PI二醉单体的电化学性质与PI-相似,分子中的共辘结构对PI二醉单体的电化学氧化还原反应有利。

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I LnCl_3-LiCl-THF配合物的研究深入地研究了氯化稀土和氯化锂于四氢呋喃溶液中,以不同的摩尔比,在不同条件下的反应。实验结果表明,反应速度随着稀土元素原子半径的减小,LiCl/LnCl_3摩尔比的增大,以及四氢呋喃用量的增加而加快。通过紫外质谱元素分析和X-射线单晶结构分析等证明,随着不同的LiCl/LnCl_3摩尔比和结晶条件的不同,可以得到不同组成的LnCl_3-LiCl-TNF配合物。对(LaCl)(THF)_2(μ_2-Cl)_4[Li(THF)_2]_2和(LaCl)DME(μ_3-Cl)(μ_2-Cl)_5(La·DME)Li(THF)_2晶体的结构分析表明,前者为单斜晶系,P21/C空间群。a=10.542(4), b=32.236(4), c=11.182(6)A °; β=113.50(3) °, V=3484.97 A °~3. Z=4, R=0.0471;后者为三斜晶系,PT空间群,晶胞参数是:a=11.123(3), b=16.564(5), c=8.653(3)A °;α=95.16(3), β=95.63(3), γ=74.71(3) °;V=1527.0A °~3。Z=2,R=0.0303。实验结果还表明,μ_2-和μ_3-氯桥键是LnCl_3-LiCl-THF类配合物中最基本、最重要的配位键,这种键是通过多重键的方式起着稳定分子结构的作用。当进行与有机配体的交换反应时,由于它们的特殊稳定性,能起到阻止轻稀土有机配合物歧化反应的作用。II环戊二烯基轻镧系氯化物的合成及其稳定性的研究对(G_5H_5)_3Ln·THF和LnCl_3·3LiCl-THF (Ln=La, Nd)溶液反应的研究表明,由于μ_2-氯桥键的作用,轻稀土环戊二烯基化合物中环戊二烯基的再分配反应,在0℃或室温下都能迅速进行。通过两者不同的摩尔比反应,经元素分析、红外光谱、~1H NMR和质谱鉴定,方便地合成了C_5H_5 LnCl_2·2LiCl·5THF和(C_5H_5)_2LnCl.LiCl·nTHF (Ln=La, Nd)等配合物。这一结果表明(C_5H_5)_2LnCl.LiCl·nTHF配合物不仅能稳定地存在于THF溶液中,而且能在一定条件下析出结晶。对(C_5H_5)_2LaCl.LiCl·4THF的晶体结构测定表明,该晶体属于正交晶系,Pc2m空间群。a=12.306(4), b=23.056(6), c=26.701(11)A°; V=7575.81A°~3;而(C_5H_5)_2LaCl·LiCl(DME)_2THF晶体则属于六方晶系,a=12.967(4), b=12.967(4), c=24.108(10)A°;V=3510 A°~3。通过(G_5H_5)_3Ln·THF与LnCl_3·3THF (Ln=La, Nd)的反应进一步研究了轻稀土环戊二烯基氯化物的稳定性。经元素分析,红外光谱和晶体结构分析表明合成了[(η~5-C_5H_5)_4La_3Cl_5·3THF]_2·9THF和(C_5H_5)_2 NdCl·THF配合物,前者属于三斜晶系,P1空间群。a=11.690(3), b=11.750(5), c=18.433(6)A°; α=98.75(3), β=95.62(3), γ=118.92(2)°; V=2147.06 A°~3. Z=1, R=0.099。对环戊二烯基轻稀土氯化物的稳定性进行了较详细地讨论。结果表明,THF的用量和化合物的溶解度是影响产物组成的决定因素。当THF的量不足以溶解所生成的产物时,就会歧化成溶解度最大((C_5H_5)_3Ln·THF)和最小(LnCl_3·nTHF)的两种组分。反之,环戊二烯基轻稀土化合物(Ln=La, Nd)中环戊二烯基的再分配反应就能顺利进行。经元素分析和结构测定,在((C_5H_5)_3Nd·THF)和NdCl_3·LiCl-THF溶液的反应体系中,偶然分离得到了[(η~5-C_5H_5)_4Nd_4(μ_4-o)(μ_2-Cl)_8] [Li(DMP)_2THF]_2这一不合常规的化合物,其晶体属于正交晶系,Pna2,空间群a=19.010(7), b=23.231(6), c=14.180(4); V=6261.91 A°~3。Z=4, R=0.054。说明在一定条件下,μ-氧桥键也起到了稳定分子结构的作用。推测了各类环戊二烯基轻稀土氯化物在THF中的合成反应机理,在LiCl存在的反应体系中Ln cl cl Li桥键能与环戊二烯基发生交换反应;在(C_5H_5)_3Ln·THF和LnCl_3·3THF的反应体系中,首先存在着LnCl_3分子之间的互相作用,因而易于形成双核或多核配合物。这类配合物以晶体形式析出时,易于发生结构上的变化,即化合物的结晶形态与溶液中的形态不一定相同。探索了环戊二烯基烯丙基稀土化合物新的合成方法。找到了真空加热脱水制备氯化稀土的最佳条件,其产物纯度在97%以上。通过加入Co_3O_4/Wo_3催化助燃剂的方法,提高了测定稀土有机化合物中碳含量的准确性。

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自1968年浅井等合成β-羧基乙基锗倍半氧化物(Ge-732),并发现其广谱抗癌和保健作用以来,有机锗化合物合成及生物活性的研究相当活跃。有机锗倍半氧化物,由于具有低毒和广泛的药理作用而倍受重视。二十年来,虽对Ge-732及其衍生物和其他有机锗化合物进行了相当广泛的研究,但作为临床便用的锗药物尚未见文献报导。另外,有机锗化合物的结构-生物活性关系也有待搞清。合成新型有机锗化合物,深入研究它们的结构和性质,进行抗癌活性试验提示其结构-活性关系,仍是十分有意义的课题,为此,我们开展了以下几个方面的研究。一、合成了Ge-732的中间体Cl_3GeCH_2CHRCOOH (R=H,CH_3)单晶,用X-射线衍射法确定了晶体和分子结构,晶体分属单斜和三斜晶系,P21/n和P1-bar空间群,Ge原子与三个Cl原子和一个羧乙基(甲基羧乙基)C原子以a键连结,形成不规则的四面体几何构型,分子靠羧基间氢键缔合为二聚体。TG-DTA和MS研究发现Ge-Cl键易断裂,是化学反应的活性部位,通过IR和Raman光谱较完整地分析了分子振动的各模式。改进了Ge-732的文献合成方法,缩短了合成时间,产率提高到80%以上。发现用不同方法制备的Ge-732由于聚合度、Ge-O大环天度及氢键强度不同,其IR光谱、热分解温度等存在一定差异。二、合成了16种β-酚酯乙基锗倍半氧化物(GeCH_2CHRCOOAr)_2O_3和8种β-烃基酰胺基乙基锗倍半氧化物(GeCH_2CHRCONHR')_2O_3,通过多种手段主宰了它们的组成和结构。IR光谱的重要特点是800 ~ 900cm~(-1)出现两个V_(Ge)吸收峰,FAB-MS证明上述衍生物结构中同样存在Ge-O-Ge-O大环,系列衍生物的Ge_3p,Ge3d电子结合能接近,说明不同衍生物中Ge原子所处的结构环境基本相同。粉末X-射线衍射谱表明(GeCH_2CHRCOOAr)_2O_3衍生物的晶体结构与Ge-732类似。因增加了酚酯或酰胺基团,亲脂性提高,能延长在体内的代射时间,而可能具有比Ge-732更强的抗癌活性。三、合成了N-(5-F尿嘧啶-N_1)酰胺基基锗倍半氧化物,通过IR光谱,元素分析确定了组成和结构,该人物可能具有抗癌和增强机体免疫功能的双重作用。四,观察了三种(GeOH_2CHRCOOAr)_2O_3对体外HeLa细胞(人宫颈癌细胞)和二倍体细胞(正常细胞)培养的影响,发现对二倍体细胞基本无影响,而对HeLa细胞分裂有相当明显的抑制作用细胞形态发迹对细胞的分裂抑制作用与苯环取代基有关,证明苯环修饰部分参予生物作用在上述实验基础上,用其中一种人物进行了载瘤鼠的给药试验,发现体内癌细胞中三种酶含量降低,因而抑制小鼠腹水癌细胞的生长。但在体外细胞培养中也发现,(GeCH_2CHRCOONHR')_2O_3对胃癌细胞分裂无明显抑制,药理作用机制可能与酚酯衍生物不完全相同。

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本文以戊二胺、已二胺、癸二胺和对-苯撑-双苯偏三酸酯二酐为单体通过溶液聚合反应制备了聚酯酰亚胺TLCP系列共聚物。采用IR,WAXD,DSC和偏光显微镜研究了共聚物的结构和液晶性能。采用TG研究了聚合物的热稳定性。共聚物红外光谱表明,在1775cm~(-1), 1712cm~(-1), 1370cm~(-1)和725cm~(-1)处表现出酰亚胺键的特征吸收峰,在1650cm~(-1), 1540cm~(-1)处并未表现出酰胺键的特征吸收峰,这说明酰亚胺化进行完全。DSC结果表明,共聚物样品第一次升温曲线上都表现出两个明显的吸热峰Tm1和Tm2,Tm1是共聚物从固态向液晶态转变的温度,而Tm2是从液晶态向各向同性状态转变的温度。Tm1和Tm2之间的温差为聚合物的介晶温度范围。我们利用正交偏光显微镜观察了共聚物的液晶态结构,结果表明,在Tm1和Tm2之间具有明显的双折射现象。而且都表现出典型的棒状或小锥状结构,这是近晶型液晶的典型结构特征。共聚物WAXD研究结果表明,在2θ ≈ 20°左右可以观察较强的衍射峰,这说明分子链横向排列间距在4.5-5.0A左右。在2θ ≤ 13°的小角范围内可以观察到多个比较尖锐衍射峰,表明聚合物分子采取较为完美的层状超分子结构顺序排列。共聚物在2θ ≈ 20°和小角范围内衍射峰的出现表明共聚物是近晶型结构。TG分析结果表明,聚合物具有较高的热稳定性;进一步,对P1进行了非等温动力学研究,结果表明其液晶级转变和结晶转变过程基本满足Avrami方程。

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两栖类动物的皮肤是其得以生存的重要器官,它担负着许多生理功能,如呼吸、水份调节、温度控制、排泄、繁殖、抵抗微生物、防御天敌等。存在于两栖动物皮肤分泌物中的生物活性成分已成为研究热点。目前,己分离鉴定出许多具有各种生物活性的蛋白质及多肤。通过三步分离纯化过程:DEAE-SephadexA-50离子交换,SephadeX075凝胶过滤,和DEAE-SephadexA-50离子交换层析,我们从大蹼铃蟾(Bombinamaxima)皮肤匀浆物中分离得到纯化的大蹼铃蟾皮肤白蛋白(Bm-A-skin)。SDS-PAGE电泳表明,该蛋白为单链蛋白质,在还原状态下表观分子量为67kDa。非还原状态下至少存在三条带,分子量分别为50,55和110kDa。经N-端氨基酸序列分析,其序列均相同,故该蛋白在SDS存在下有同分异构体及多聚体形式。根据所测得的N端氨基酸序列及内肤序列设计引物,通过筛选已构建的大蹼铃蟾皮肤cDNA文库,获得了编码该蛋白的全长cDNA。经序列分析发现该蛋白由三个保守的血清白蛋白结构域组成,并且同人血清白蛋白及牛血清白蛋白的序列相似度分别为39%和38%。随后,我们从血清中也分离纯化到血清白蛋白(BmA-serum),并通过RT-PCR,从大蹼铃蟾肝脏中扩增得到其全长cDNA序列。对由cDNA序列推导的两个大蹼铃蟾白蛋白的氨基酸序列进行比较,发现二者基本相同,只有两个氨基酸的差异,即BmA-skin的Gly417,Ser569,在BmA-serum中均为Asn。造成这两个氨基酸差异的只有一个碱基的突变,即编码BmA-skinGly417,Ser569密码子的第二位碱基A在BmA-serum中变为G。另外,从肝脏获得的BmA-serum的cDNA3'非翻译区还有8个碱基的插入。经扫描光谱分析,BmA-skin含有大量的血红素b,含量为0.95moFinol蛋白,而BmA-serum中含量较少,为0.05mol/mol蛋白。经schiff试剂染色发现,BmA-skin及BmA-serum均为非糖蛋白质。两者均具有抑制trypsin水解小肚底物的活性,但对其它丝氨酸蛋白酶的活性则无抑制,如thrombin、chyomotryPSin、elastase及substilisin。利用表面等离子共振技术研究BmA-skin及BmA-serum与trysin的相互作用,分别得到它们与trrpsin结合的动力学常数,解离平衡常数KD为两者均通过由一对二硫键cys53-Cys62形成的一个暴露的活性位点环,以1:1分子摩尔比同tryrsin形成稳定的非共价结合的复合物,其反应活性位点为Arg58(P1)-His59(P1')。利用免疫组织化学方法研究发现,BmA-skin广泛地分布于成年大蹼铃蟾上皮细胞的细胞膜及真皮的疏松结缔组织层。表明其在蛙皮肤的生理功能中发挥重要作用,如水及代谢物质交换,渗透压的维持,皮肤呼吸等。另外,我们还从非洲爪蟾(xenopus勿即is)的血清及皮肤中分离到其68扔a的血清白蛋白,经初步鉴定也具有trtPsin抑制活性,但其抑制机制与B.maxima白蛋白不同,还有待于进一步研究。通过MTT法研究发现,BmA-skin对人T淋巴细胞H9、C8166及hemin处理的红白血病细胞K562具有细胞毒活性。三种细胞经BmA-skin处理72h,CC50A片段化,细胞核形态变化及流式细胞仪分析,结果显示,BmA-skin具有选择性诱导细胞调亡的特性。而BmA-serum对三种细胞均无毒性作用,单独的hemin对三种细胞的,胜也很弱。实验结果表明,BmA-skin结合的血红素b可能对其细胞毒及诱导细胞调亡的活性具有较大的贡献。用Cy3标记的BmA-skin与Hg和C8166细胞保温后,发现其进入细胞内发挥作用,这可能是其诱导细胞调亡机制之一。

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目前对PVA生物降解研究重点逐渐转移到对PVA降解菌和PVA降解酶的研究开发上,随着对PVA降解高效新菌株的不断发现和PVA降解酶作用机理和分泌机制的深入了解,利用高效微生物或酶法治理PVA这类高聚物的污染将具有较大的应用潜力。本论文研究工作正是基于这种客观条件下进行的,对本实验室前期分离的PVA降解菌株P1、共生菌B1+B2、Pa、Pb为研究对象,重点研究了菌株P1和共生菌B1+B2的产酶条件和产酶特性,验证找出了影响菌株P1产酶的生长因子,论证了菌株B1+B2的产酶特性,优化得出了菌株B1+B2的最佳产酶条件;然后对共生菌B1+B2的PVA降解酶的稳定性进行了研究;最后研究了最佳组合菌的产酶特性和最佳产酶条件。主要研究结果如下: 1 通过对菌株P1产酶因子的研究,找出了核黄素是菌株P1产酶的必须因子,在以淀粉为碳源时,核黄素只是产酶的必须因子,而不是菌体生长的必须因子;在以PVA为碳源时,核黄素既是生长的必须因子,也是产酶的必须因子,是菌株P1的生长因子。 2 对共生菌B1+B2的产酶条件和产酶特性进行了研究,并通过正交实验找出了影响菌株产酶的主要条件和菌株产酶的最佳条件。 3 对共生菌PVA降解酶的稳定性进行了研究,确定了影响酶稳定性的主要理化条件。 4 通过对菌株降解性能的比较,确定菌株Pa、Pb、共生菌、P1的作为组合菌的组成菌,然后通过复配实验确定出菌株的最佳组合为菌株Pa、P1、共生菌,最后通过正交实验确定最佳组合菌的最佳配比。 5对影响组合菌产酶的因素进行了研究,通过正交实验确定了影响组合菌产酶的主要因素和最佳产酶条件。 本文通过对PVA降解菌株产酶条件和特性的研究,旨在为PVA降解菌生产酶制剂及进一步优化PVA降解菌在PVA废水治理中的应用提供理论和应用依据。 Now the PVA-degrading bacteria and polyvinyl alcohol-degrading enzyme are the key studies on the PVA biological degradation. It has great application potential using special bacteria and enzyme to treat pollution of PVA, with some high efficient Strain and enzyme were found. The study of this paper was based on that objective condition. The stain P1, symbiotic bacteria B1+B2, stain Pa and strain Pb were studied .The conditions of enzyme production and enzyme production characteristic of stain P1, symbiotic bacteria B1+B2 were our key study, we tested and verified the growth factor which effected enzyme production of strain P1, demonstrated enzyme production characteristic of symbiotic bacteria B1+B2, optimized and obtained the optimum conditions of enzyme production; then we studied the stability of polyvinyl alcohol-degrading enzyme of strain B1+B2; last the enzyme characteristic and the optimum conditions of alcohol-degrading enzyme production of optimum combination stains were studied. The main study results are below: 1. Through the study of enzyme production factor we found that lactoflavin is the necessary factor in strain P1 enzyme production. When we used starch to be carbon energy, lactoflavin is only the necessary factor of enzyme production, but not growth factor. When we used PVA to be carbon energy, lactoflavin was not only the necessary growth factor ,but also the necessary enzyme production factor.So it was the growth factor of strain P1 2. The enzyme production conditions and enzyme production characteristic of symbiotic bacteria B1+B2 were studied. Through the orthogonal experimental design, the main conditions which effected the enzyme production and the optimum conditions of enzyme production were obtained 3. Through the study of the stability of polyvinyl alcohol-degrading enzyme, the main physical and chemical conditions which effected the enzyme stability were 4. The stain P1,symbiotic bacteria B1+B2, stain Pa and strain Pb were selected to form combination bacteria. The stain P1,symbiotic bacteria B1+B2,stain Pa were the optimum combination through duplication experiment. Then the optimum ratio was obtained through orthogonal experiment. 5. Studied the factors which effected the polyvinyl alcohol-degrading enzyme activity, then through orthogonal experiment, the main factors and condition of enzyme production which effected the combination bacteria were achieved. The result of the study was valuable for the ferment of the PVA-degrading enzyme and the optimization of the PVA-degrading performance in the PVA wastewater.