Decolorization of textile dyes by Bjerkandera sp. BOL 13 using waste biomass as carbon source

BACKGROUND: Phanerochaete chrysosporium, Trametes versicolor and Bjerkandera sp BOL13 were compared for decolorization of azo dyes supplied individually or as a mixture. The dye decolorization was also evaluated during continuous treatment under non‐sterile conditions using a lignocellulosic growth substrate. RESULTS: Bjerkandera sp BOL13 showed the highest dye decolorization potential. This fungus was also found to support high decolorization of Remazol Red RR at an initial pH of 4‐6 and when using straw as co‐substrate. The fungus was evaluated for Remazol Red RR decolorization in a continuously fed packed‐bed bioreactor operated under non‐sterile conditions with 3 days of hydraulic retention time. When glucose was supplied as growth‐substrate, decolorization efficiencies of 65‐90% were maintained for 12 days in a bioreactor packed with wooden material. The decolorization efficiency was lower when glucose was not fed to the fungus or when a plastic material was used as packing. Higher manganese peroxidase and laccase activities were also recorded when the wood packing was used. Contamination caused a drop in decolorization efficiency after 17‐19 days operation. CONCLUSIONS: The potential of Bjerkandera sp BOL13 for decolorization of azo dyes under non‐sterile conditions using lignocellulosic growth substrates was demonstrated. Research is needed to reduce contamination under non‐sterile conditions. © 2012 Society of Chemical Industry     

白腐菌预处理对稻草化学组分及酶水解的影响

采用5株白腐菌预处理稻草,对预处理过程中产生的木质纤维素降解酶系以及稻草化学组分变化进行了分析,研究了预处理对后续纤维素酶水解效率的影响。研究结果表明,5株白腐菌在预处理期间(0~50天)均能检测到漆酶(Lac)、锰过氧化物酶(MnP)和纤维素酶(Cel)活性,但未检测到木质素过氧化物酶(LiP)活性。其中凤尾菇培养第20天Lac活性达到最高,为2244 U/L;平菇培养40天MnP活性最高,达771 U/L;凤尾菇和平菇的木质素降解选择性指数(SI)随着预处理时间延长呈上升趋势,培养至50天时平菇的SI达到1.87,比其它4株白腐菌表现出更好的选择性降解木质素能力。云芝4号、平菇和凤尾菇表现出良好的预处理效果,经此3菌株预处理50天的稻草粉,在每克底物20 FPU酶用量条件下用纤维素酶水解48 h,酶水解总糖转化率分别达到59.6%、56.3%和54.4%。     

白腐真菌煤渣生物膜反应器对染料废水的脱色试验研究

白腐真菌煤渣生物反应器处理模拟活性艳红染料废水,菌种Ａ、Ｂ（担子菌纲）和Ｃ（云芝）最高脱色率分别达到８４％、８０％和９５％。试验表明,共培养液类型对染料的脱色效果有明显影响,菌种Ｃ受共培养液的影响最为显著。白腐真菌煤渣生物膜反应器对实际的偶氮染料废水的脱色作用主要在初始阶段完成,而到７２ｈ后ＣＯＤ得以有效去除。当该废水的初始ＣＯＤｃｒ为６０００ｍｇ／Ｌ时,经１４４ｈ后,ＣＯＤｃｒ的去除率达９８％。     

TNT红水治理研究新动态

综述了国内外治理TNT红水的研究现状及发展趋势,阐明了生化治理TNT红水的难点,给出了采用经红水驯化后的白腐菌生化治理TNT红水的技术措施、脱色方法及分析方法,指出白腐菌与木质素载体能较有效地降解TNT红水,该方法具有广阔的应用前景,同时对白腐菌处理技术的发展和应用提出建议.     

Pectobacterium parmentieri SCC 3193 Mutants with Altered Synthesis of Cell Surface Polysaccharides Are Resistant to N4-Like Lytic Bacteriophage ϕA38 (vB_Ppp_A38) but Express Decreased Virulence in Potato (Solanum tuberosum L.) Plants

Pectobacterium parmentieri is a Gram-negative plant-pathogenic bacterium able to infect potato (Solanum tuberosum L.). Little is known about lytic bacteriophages infecting P. parmentieri and how phage-resistance influences the environmental fitness and virulence of this species. A lytic phage vB_Ppp_A38 (ϕA38) has been previously isolated and characterized as a potential biological control agent for the management of P. parmentieri. In this study, seven P. parmentieri SCC 3193 Tn5 mutants were identified that exhibited resistance to infection caused by vB_Ppp_A38 (ϕA38). The genes disrupted in these seven mutants encoded proteins involved in the assembly of O-antigen, sugar metabolism, and the production of bacterial capsule exopolysaccharides. The potential of A38-resistant P. parmentieri mutants for plant colonization and pathogenicity as well as other phenotypes expected to contribute to the ecological fitness of P. parmentieri, including growth rate, use of carbon and nitrogen sources, production of pectinolytic enzymes, proteases, cellulases, and siderophores, swimming and swarming motility, presence of capsule and flagella as well as the ability to form biofilm were assessed. Compared to the wild-type P. parmentieri strain, all phage-resistant mutants exhibited a reduced ability to colonize and to cause symptoms in growing potato (S. tuberosum L.) plants. The implications of bacteriophage resistance on the ecological fitness of P. parmentieri are discussed.     

52%的菌核·锰锌对烟草赤星病菌的室内及田间毒力测定

室内采用孢子萌发抑制法测定菌核净、代森锰锌以及它们的复配剂52%菌核·锰锌对烟草赤星病菌的毒力,结果表明,菌核净和代森锰锌以适当的比例复配,可明显提高其对烟草赤星病菌孢子萌发的抑制率.计算复配剂共毒系数为385.081 9,表现出增效作用.田间防治试验亦表明,该复配剂可有效地控制赤星病的发生和危害.     

甜菜机械化栽培的机械改装配套及作业标准的研究

通过深翻深松 ,使耕层达到 30cm左右 ,有利于甜菜块根膨大生长 ,并使根腐病发病率降低 2 2 6 %。利用限深轮 ,使甜菜播种深度控制在 3cm为宜。按 7cm、1 2cm和 1 7cm分层施肥 ,能提高肥料利用率。苗期行间深松 2 5cm以上 ,可大大促进幼苗生长。机械起甜菜的机具入土深度以 30cm为宜。采用本项农机农艺配套技术 ,可使每亩增加 0 81t甜菜 ,单产提高 38 9% ,并使块根含糖率增加 0 6 8°S。     

Rapid determination of ergosterol in grape mashes for grape rot indication and further quality assessment by means of an industrial near infrared/visible (NIR/VIS) spectrometer – A feasibility study

Perceptual quality and food safety of grape products like wine is generally impaired by grape rot. Commonly applied visual inspection for quality assessment remains subjective. However, conventional analytical determinations are tedious and time-consuming. In contrast, near infrared/visible (NIR/VIS) spectroscopy is an objective and rapid alternative. An industrial spectrometer especially designed for on-line process integration was applied in laboratory configuration to evaluate the feasibility of the prediction of ergosterol and 12 further quality-associated parameters in grape mashes. Calibration models were established, validated, and evaluated. Spectral ranges used were 450–850 nm (VIS) and 1050–1650 nm (NIR). The regression method applied was partial least squares (PLS) regression. Calibrations at best suitable for discriminating low and high values were obtained for gluconic, acetic, tartaric, and titratable acids contents, pH value, ethanol content, and laccase activity. Therefore, for these parameters limits of NIR/VIS spectroscopy may be revealed. Calibrations for semi-quantitative predictions or rough estimations were obtained for fructose, glucose, and malic acid contents. Best performance suitable for quantitative predictions was achieved for relative density, glycerol, and ergosterol contents. The industrial spectrometer proved to perform similar to a research laboratory spectrometer. Consequently, a future on-line implementation of NIR/VIS spectrometers in wineries may be a valuable and reliable tool for rapid grape quality assessment at reception. Particularly, ergosterol content prediction proved to be a promising measure for efficient and immediate quality control and management, respectively. Wine quality and food safety may be increased. Fair and incentive pricing of delivered grapes may be enabled.     

Evaluation of basidiomycetous fungi for pretreatment of contaminated soil

BACKGROUND: For most dioxin‐contaminated sawmill soils, combustion is recommended. However, the process may be inefficient if the soil has a high organic matter content. The use of saprotrophic basidiomycetous fungi is an alternative for pretreatment of this kind of soil. A total of 147 fungi were evaluated for their ability to grow in sawmill soil. From this screening, the best soil colonizing fungi were selected to study their enzyme activities and degradation of soil organic matter. Pine (Pinus sylvestris) bark was used as a co‐substrate to propagate the fungi into the soil. The activities of manganese peroxidase (MnP), laccase, endo‐1,4‐β‐glucanase, endo‐1,4‐β‐xylanase, and endo‐1,4‐β‐mannanase were analysed from the inocula and fungal treated soil. RESULTS: The screening revealed that 56 out of 147 fungi were able to grow in non‐sterile soil, and most of them were litter‐decomposing fungi (LDF). In pine bark cultures, the highest enzyme activities were observed with Phanerochaete velutina, which produced 5 U g^?1 of MnP. The activity of endo‐1,4‐β‐glucanase was generally higher than that of other hydrolytic enzymes. The highest carbon loss from soil with a high organic matter content was achieved by P. velutina (3.4%) and Stropharia rugosoannulata (2.4%). CONCLUSIONS: Many LDF, and in addition the white‐rot fungus P. velutina, are potential degraders of soil organic matter since they showed good growth and respiratory activity. Pine bark was a suitable lignocellulosic co‐substrate and a good promoter of MnP activity. Copyright © 2009 Society of Chemical Industry     

新型细胞固定化载体强化白腐菌降解活性染料

为提高白腐真菌的产酶能力和后续对染料的降解效果,采用摇瓶试验研究新型细胞固定化载体——聚氨酯泡沫固定化白腐真菌后的锰过氧化物酶(MnP)产生情况以及后续对活性染料——活性艳红K-2BP的降解效果.结果显示,新型载体固定化培养白腐真菌的5d脱色率为95%,比悬浮培养7d的脱色率高15%.固定化培养产生的MnP酶活为936.61U/L,而悬浮培养的MnP仅为269.52U/L,并且酶活高峰期提前4d.另外,固定化培养体系中碳、氮源的消耗比悬浮培养快很多,而且固定化培养使得白腐真菌具有较高的H2O2产量.因此,新型细胞固定化载体强化白腐真菌降解活性染料的原因应归于这种培养体系碳、氮源的快速消耗而带来的MnP酶活的提高和高H2O2产量.