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固定化白腐菌对造纸废水的生物降解研究 总被引:6,自引:0,他引:6
就具有较强木质素降解能力的白腐菌对造纸废水的降解效果及条件进行了初步研究.分别采用固定化白腐菌和悬浮态白腐菌在不同接种量下对造纸废水进行降解,对降解过程中的白腐菌生长量、pH、COD、木质素含量等废水降解指标进行测定.结果显示两种不同状态下的白腐菌均能降解造纸废水,但它们的降解程度不同.其中固定化白腐菌降解木质素效果较好,且呈现较明显规律,说明固定化的白腐菌较悬浮态的白腐菌更具有降解造纸废水的潜在能力. 相似文献
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经高温碱性盐法预处理的玉米秸秆预处理液中木质素和碱性盐含量高,为了反复利用含盐预处理液,需脱除其中的可溶性木质素。本实验从腐木中筛选分离到一株木质素降解菌株CCZU-WJ6,通过形态学观察和16S rDNA序列分析,鉴定该菌株属于无色杆菌属(Achromobacter sp.)。测定了CCZU-WJ6木质素降解相关酶的活性,及其在玉米秸秆预处理液中的生长趋势、预处理液的COD去除率和木质素降解率,通过GC-MS和FTIR检测预处理液中组分及其化学键的变化。通过单因素实验确定了菌株CCZU-WJ6处理预处理液的最佳条件为pH 7.0、温度30℃、预处理液稀释倍数10倍、接菌量0.5g/mL。在处理6天后,预处理液COD脱除率为40.9%,木质素的降解率为32.1%,CCZU-WJ6分泌木质素过氧化物酶和锰过氧化物酶的酶活分别达到215.5U/L、200.1U/L。CCZU-WJ6会破坏木质素结构中的苯环结构、醚键以及C=O键,降解产物中含有愈创木酚和对香豆酸,推断其降解途径为β-芳基醚代谢途径和阿魏酸代谢途径。CCZU-WJ6可用来处理含木质素的工业废水,在工业方面具有广阔的应用前景。 相似文献
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利用聚合氯化铝-聚丙烯酰胺处理稻草NH4OH-KOH蒸煮黑液。系统讨论了聚合氯化铝用量、聚丙烯酰胺用量、反应温度和黑液pH值等工艺参数对絮凝效果的影响,继而确定了适宜絮凝工艺条件。结果表明,该絮凝体系对黑液COD去除率为68%,木质素去除率为92%。仪器测试表明絮凝沉淀物中除含有大量木质素外,氮、钾等营养元素的含量分别为23. 73%、6. 24%(均为干基),为絮凝沉淀物制备固体有机肥料创造条件;上层清液pH 为9. 20,呈碱性,杂质含量低,补加NH4OH/KOH后可作为蒸煮液循环使用,使稻草制浆更易于实施清洁生产。 相似文献
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白腐菌降解木质纤维素顺序规律的研究 总被引:19,自引:0,他引:19
通过纤维素、半纤维素和木质素三者含量变化的测定,以及傅立叶变换红外光谱(FTIR)的谱图分析,研究了 BP2、CD1和 AX3三株白腐菌在50 天培养期中降解木屑基质中木质纤维素的规律。结果表明,三株白腐菌对木屑基质中纤维素、半纤维素和木质素三者的降解具有一定的顺序和选择性,即先降解半纤维素和木质素,再同时降解半纤维素、纤维素和木质素;从降解比例来看,三株菌对木质素具有很强的降解优势(45%左右)和选择性(0.5左右)。木质素的相关谱带(1630,1510,1325 和 1265 cm-1)强度及半纤维素和纤维素的相关谱带强度(1740,1325,1160 和 898 cm-1)的变化也证实了这一结论。 相似文献
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选择性降解木质素白腐菌筛选的研究 总被引:7,自引:0,他引:7
对国内外15种产漆酶的白腐菌进行初步筛选,从中获得7株产漆酶活性较高的菌株。经对木材降解能力的分析及在培养过程中所产各种酶酶活的测定,得到了2株产漆酶酶活高、降解木质素选择性优良的菌株,其中Flammulinavelutipes和My-1两菌株经14天液体培养,漆酶酶活高达214IU/mL和231IU/mL。杨木经其处理30天后木质素降解率达到22.67%和15.46%。 相似文献
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Peng Dangcong Jin Qiting 《Journal of chemical technology and biotechnology (Oxford, Oxfordshire : 1986)》1993,58(1):89-93
The anaerobic digestion of alkaline black liquor from a cereal straw pulping mill was studied in batch (serum bottles) and continuous systems (up-flow anaerobic sludge blanket reactor—UASB). The batch digestion studies confirmed that lignin and related compounds (LRC) in the alkaline black liquor were the main inhibitory substances and could not be decomposed by anaerobic bacteria. At organic loading rates of 5–10 kg COD m?3 day?1, the UASB reactor achieved 50–60% COD removal efficiencies. Gas production was 2–3 dm3 per dm3 of alkaline black liquor. Two different sludge types were examined in the reactor: granular and cluster-like sludges. Sludge in a cluster, which involved many small granules and flocs, tended to form larger aggregates and possessed good settling ability. 相似文献
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白腐菌Cyathus stercoreus预处理芦苇制浆的研究 总被引:3,自引:0,他引:3
对用白腐菌Cyathus stercoreus预处理芦苇制取化学浆进行了研究。实验结果表明,用Cyathus stercoreus固体发酵处理后的芦苇所制烧碱—蒽醌浆的白度和粘度要低于未经发酵处理的对比浆的白度和粘度,而Kappa值高于对比浆;这个结果表明,白腐菌Cyathus stercoreus 对芦苇中的纤维素,半纤维素和木质素均有不同程度的降解能力,且对纤维素和半纤维素的降解要高于对木素的降解。且在白腐菌Cyathus stercoreus预处理过程中所分泌的各种木素降解酶的作用下,芦苇木素既发生降解,也发生一定程度的聚合。 相似文献
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Abstract The lignin degradation by Flavodon flavus (Klotzsch) Ryv. and Schizophyllum commune Fr. on Mangifera indica and Syzygium cumini wood, changes in the chemical composition of the degraded wood, and production of extra-cellular lignocellulolytic enzymes were analyzed. White rot fungi F. flavus and S. commune selectively degraded the lignin of S. cumini rather than the holocellulose component, whereas simultaneous degradation of lignin occurred in the case of M. indica. After 90 days of pretreatment with F. flavus, total weight loss was 29% and loss in lignin content was 25.7% in M. indica wood. However, 8% loss of holocellulose was caused by S. commune in S. cumini wood. Extracellular enzymes from F. flavus such as ligninase and cellulase showed higher activity in degradation of M. indica wood than in S. cumini wood. Weight loss and changes in chemical composition of M. indica and S. cumini woods showed good correlation with enzyme activity in lignocellulose degradation. Woods of S. cumini showed resistance to the white rot fungi could be due to the presence of polyphenols. 相似文献
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Abstract Black liquor, isolated dissolved lignin and residual lignin samples corresponding to different cooking times were obtained from flow-through kraft cooking of birch wood. Dissolved lignin was isolated from black liquor by acid precipitation and residual lignin was isolated from pulp by acid-dioxane extraction. The average mobility (μav) of the lignin-containing samples was determined by capillary zone electrophoresis. The lignin samples have a broad mobility distribution that reflects the charge-to-size ratio of the molecules. At pH 12, i.e. when lignin is completely dissociated, the μav of each type of sample increases during the cook, reflecting an increase in charge density of the lignin. For samples corresponding to the initial and beginning of the bulk delignification phases, the μav decreases in the order dissolved lignin>black liquor>residual lignin. The lower charge density of black liquor compared to dissolved lignin is proposed to be caused by associations between lignin and carbohydrate fragments dissolved in the black liquor. As from the middle of the bulk delignification phase, the μav of the three series of samples is quite similar. The decrease in mobility on lowering the pH is an indication of the degree of dissociation of the lignin phenol groups. At pH 10, i.e. about the pKa of lignin, the μav of black liquor is highest throughout the cook. The relative order of μav is then black liquor>dissolved lignin≈residual lignin. 相似文献