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Lignin Peroxidase (lignin + peroxidase)
Selected AbstractsOptimization of extraction of bulk enzymes from spent mushroom compostJOURNAL OF CHEMICAL TECHNOLOGY & BIOTECHNOLOGY, Issue 7 2003Avneesh D Singh Abstract The profiling of ligninase, hemicellulase and cellulase of Pleurotus sajor-caju after inoculation of spawn in bags containing sawdust was done at monthly intervals for a period of 6 months. Xylanase (EC 3.2.1.8) was produced throughout the 6 months studied with the productivity range from 5.60 to 7.51 U g,1. Cellulase (EC 3.2.1.4) and ,-glucosidase (EC 3.2.1.21) productivities were highest at 4 months, producing 3.31 U g,1 and 121.13 U g,1 respectively. Laccase (EC 1.10.3.2) productivity was highest at 2 months with a value of 7.59 U g,1. Lignin peroxidase (EC 1.11.1.14) productivity was highest at 5 months with a value of 206.20 U g,1. Total soluble proteins were highest at 4 months with a value of 0.139 mg cm,3. The profiling of lignin peroxidase in 5-month-old spent mushroom compost was monitored over a period of 10 months. It was observed that lignin peroxidase was produced throughout the period but productivity was variable. The average lignin peroxidase productivity ranged from 30 to 110 U g,1. The activities of the enzymes extracted in tap water at pH 8.4 were comparable to that extracted in 50 mmol sodium citrate buffer at pH 4.8 and distilled water at pH 5.2 at 4 °C using an incubator shaker at 200 rpm for 18 h. The optimum extraction time was 1 h using an incubator shaker at 4 °C. When an incubator shaker was used, there was no significant difference in the recovery of xylanase, cellulase and laccase at different pH values at 4 °C and 28 °C. No significant difference was observed in the recovery of ,-glucosidase using an incubator shaker at different pH values at 4 °C although the enzyme recovery was slightly higher at pH 8.12, with a value of 29.27 U g,1. The optimum extraction of ,-glucosidase was at pH 4 at room temperature using an incubator shaker. For the lignin peroxidase enzyme, the optimum pH for extraction was 6 at 4 °C and pH 7 at room temperature using an incubator shaker at 200 rpm for 1 h. Homogenization for 8 min at 8000 rpm using tap water at pH 4 had an advantage over the use of the incubator shaker for the extraction as high titers of enzymes were recovered. Copyright © 2003 Society of Chemical Industry [source] In vitro characterization of Inocutis jamaicensis and experimental inoculation of Eucalyptus globulus standing treesFOREST PATHOLOGY, Issue 5 2009S. Lupo Summary Lesions of variable size, associated with the hymenomycete Inocutis jamaicensis, a white-rot fungus, have been observed on the stems of Eucalyptus globulus trees in Uruguay. The aim of this study was to evaluate some ecophysiological characteristics of I. jamaicensis and assess its ability to colonize E. globulus trees of two different seed origins (Geeveston and Jeeralang) and the clone, 334-1-AR, obtained by micropropagation (ENCE, Spain). The growth of an I. jamaicensis isolate (MVHC11379) was evaluated at 25°C in a medium with a water potential of 0 (, = 0). The growth rate did not vary significantly with a growth medium pH of between 4 and 7. I. jamaicensis showed no growth at either 5 or 37°C at any pH or , tested. Weight loss of heartwood and sapwood of different plant provenances inoculated with I. jamaicensis under laboratory conditions was evaluated, and significant differences observed. Lignin-modifying enzyme activity was evaluated in culture medium with or without E. globulus sawdust as substrate or inducer. Laccase activity was observed with sawdust and manganese peroxidase activity with and without sawdust. Only slight activity of aryl-alcohol oxidase and lignin peroxidase was detected without sawdust. Experimental inoculation with I. jamaicensis of 3-year-old Geeveston and Jeeralang, and of 4-year-old 334-1-AR stems, resulted in successful fungal colonization of 56% of the 334-1-AR, 50% of Geeveston and 25% of Jeeralang trees. Only the heartwood was decayed. In 334-1-AR, the rotted wood was delimited by a reaction zone. Wood characteristics and the ability of I. jamaicensis to overcome the chemical reactions in the tree could partially explain differences in susceptibility to the fungus among provenances observed under natural and laboratory conditions. [source] Biodegradation of disperse textile dye Brown 3REL by newly isolated Bacillus sp.JOURNAL OF APPLIED MICROBIOLOGY, Issue 1 2008Abstract Aims:, To isolate the potential micro-organism for the degradation of textile disperse dye Brown 3 REL and to find out the reaction mechanism. Methods and Results:, 16S rDNA analysis revealed an isolate from textile effluent contaminated soil as Bacillus sp. VUS and was able to degrade (100%) dye Brown 3REL within 8 h at static anoxic condition. A significant increase in the activities of lignin peroxidase, laccase and NADH-DCIP reductase was observed up to complete decolourization of Brown 3REL. The optimum temperature required for degradation was 40°C and pH 6·5,12·0. Phyto-toxicity and chemical oxygen demand revealed nontoxic products of dye degradation. The biodegradation was monitored by UV,VIS, FTIR spectroscopy and HPLC. The final products 6,8-dichloro-quinazoline-4-ol and cyclopentanone were characterized by gas chromatography-mass spectrometry. This Bacillus sp. VUS also decolourized (80%) textile dye effluent within 12 h. Conclusions:, This study suggests that Bacillus sp. VUS could be a useful tool for textile effluent treatment. Significance and Impact of the Study:, The newly isolated Bacillus sp. VUS decolourized 16 textile dyes and textile dye effluent also. It achieved complete biodegradation of Brown 3REL. Phytotoxicity study demonstrated no toxicity of the biodegraded products for plants with respect to Triticum aestivum and Sorghum bicolor. [source] Tyrosinase and peroxidase production by Rhizopus oryzae strain ENHE obtained from pentachlorophenol-contaminated soilJOURNAL OF CHEMICAL TECHNOLOGY & BIOTECHNOLOGY, Issue 10 2008Hugo León-Santiesteban Abstract BACKGROUND: The aim of this study was to investigate the ability of a zygomycete isolated from pentachlorophenol (PCP)-contaminated soil to produce peroxidase and phenoloxidase enzymes, and to determine the effect of tyrosine and PCP on the enzyme activities. The ability of the isolate to tolerate and remove PCP was also studied. RESULTS: A zygomycete capable of tolerating and removing PCP was isolated from contaminated soil and identified by molecular techniques as Rhizopus oryzae strain ENHE. This fungus produced extra- and intracellular tyrosinase and extracellular lignin peroxidase. Tyrosinase activity increased with 0.1 g tyrosine L,1 added to the culture medium. PCP had no effect on tyrosinase activity but increased lignin peroxidase activity. It was shown that R. oryzae ENHE grew until 100 mg PCP L,1 and removed 90% of the initial PCP concentration of 12.5 mg L,1 in 24 h and that the enzymes tyrosinase and lignin peroxidase were probably involved in the PCP removal process. CONCLUSION: The results indicate that R. oryzae ENHE has the potential to be used to produce tyrosinase and lignin peroxidase enzymes. In the few studies that report the production of peroxidase and extracellular tyrosinase by fungi, these enzymes are produced mainly by basidiomycetes. Copyright © 2008 Society of Chemical Industry [source] Improvement of the catalytic performance of lignin peroxidase in reversed micellesJOURNAL OF CHEMICAL TECHNOLOGY & BIOTECHNOLOGY, Issue 1 2008Jing Lan Abstract BACKGROUND: Anionic surfactant sodium bis (2-ethylhexyl) sulfosuccinate (AOT) had an inhibiting effect on lignin peroxidase (LiP). To improve the catalytic activity of LiP in an AOT reversed micelle in isooctane, nonionic surfactant polyoxyethylene lauryl ether (Brij30) was incorporated into the interfacial membrane. H2O2 played dual roles in the LiP-catalyzed oxidation of substrates. To obtain a sustainable high activity of LiP, a coupled enzymatic reaction, i.e. the glucose oxidase (GOD)-catalyzed oxidation of glucose was used as an H2O2 source. RESULTS: Owing to modification of the charge density of the interfacial membrane, the activity of LiP in an optimized AOT/Brij30 reversed micellar medium (,B (the molar percentage of Brij30) = 0.53, ,0 ([H2O]/([AOT] + [Brij30]) = 23, pH = 4.8) was 40 times that in a single AOT reversed micelle. Due to the controlled release of H2O2, the concentration of H2O2 in the mixed reversed micellar medium was maintained at a moderately high level throughout, which made the LiP-catalyzed oxidation of substrates proceed at a higher conversion rate than counterparts in which H2O2 was supplied externally in one batch at the beginning of the reaction. Decolourization of two waterless-soluble aromatic dyes (pyrogallol red and bromopyrogallol red) using LiP coupled with GOD in the medium also demonstrated that a higher decolourization percentage was obtained if H2O2 was supplied enzymatically. CONCLUSION: The proposed measures (both physicochemical and biochemical) were very effective, giving significant improvement in the catalytic performance of LiP in a single AOT reversed micelle in isooctane, which helped to degrade or transform hydrophobic aromatic compounds with LiP in reversed micelles more efficiently. Copyright © 2007 Society of Chemical Industry [source] Optimization of extraction of bulk enzymes from spent mushroom compostJOURNAL OF CHEMICAL TECHNOLOGY & BIOTECHNOLOGY, Issue 7 2003Avneesh D Singh Abstract The profiling of ligninase, hemicellulase and cellulase of Pleurotus sajor-caju after inoculation of spawn in bags containing sawdust was done at monthly intervals for a period of 6 months. Xylanase (EC 3.2.1.8) was produced throughout the 6 months studied with the productivity range from 5.60 to 7.51 U g,1. Cellulase (EC 3.2.1.4) and ,-glucosidase (EC 3.2.1.21) productivities were highest at 4 months, producing 3.31 U g,1 and 121.13 U g,1 respectively. Laccase (EC 1.10.3.2) productivity was highest at 2 months with a value of 7.59 U g,1. Lignin peroxidase (EC 1.11.1.14) productivity was highest at 5 months with a value of 206.20 U g,1. Total soluble proteins were highest at 4 months with a value of 0.139 mg cm,3. The profiling of lignin peroxidase in 5-month-old spent mushroom compost was monitored over a period of 10 months. It was observed that lignin peroxidase was produced throughout the period but productivity was variable. The average lignin peroxidase productivity ranged from 30 to 110 U g,1. The activities of the enzymes extracted in tap water at pH 8.4 were comparable to that extracted in 50 mmol sodium citrate buffer at pH 4.8 and distilled water at pH 5.2 at 4 °C using an incubator shaker at 200 rpm for 18 h. The optimum extraction time was 1 h using an incubator shaker at 4 °C. When an incubator shaker was used, there was no significant difference in the recovery of xylanase, cellulase and laccase at different pH values at 4 °C and 28 °C. No significant difference was observed in the recovery of ,-glucosidase using an incubator shaker at different pH values at 4 °C although the enzyme recovery was slightly higher at pH 8.12, with a value of 29.27 U g,1. The optimum extraction of ,-glucosidase was at pH 4 at room temperature using an incubator shaker. For the lignin peroxidase enzyme, the optimum pH for extraction was 6 at 4 °C and pH 7 at room temperature using an incubator shaker at 200 rpm for 1 h. Homogenization for 8 min at 8000 rpm using tap water at pH 4 had an advantage over the use of the incubator shaker for the extraction as high titers of enzymes were recovered. Copyright © 2003 Society of Chemical Industry [source] Involvement of lignin peroxidase in the decolourization of black olive mill wastewaters by Geotrichum candidumLETTERS IN APPLIED MICROBIOLOGY, Issue 1 2005L. Ayed Abstract Aim:, Decolourization of black olive mill wastewaters (OMW) by depolymerization of phenolic compounds by Geotrichum candidum. Methods and Results:, Our results show that G. candidum is able to grow on black OMW supplemented with carbon source and nitrogen. The Geotrichum growth decreased the pH and induced a 49% of colour removal when the black OMW was supplemented with glycerol and diammonium tartrate (20 mm ammonium). An improvement of 10% of colour removal was observed when the culture was supplemented with veratryl alcohol. The decolourization was inhibited with glutamate as nitrogen source. Conclusion:, Our results suggest the potential use of G. candidum in black OMW decolourization and support the concept that lignin peroxidase (LiP) of G. candidum is involved in the depolymerization of phenolic compounds. Significance and Impact of the Study:, This is the first report of LiP production by G. candidum on OMW. [source] Olive Oil Mill Waste Waters Decoloration and Detoxification in a Bioreactor by the White Rot Fungus Phanerochaeteflavido-albaBIOTECHNOLOGY PROGRESS, Issue 3 2002P. Blánquez Olive oil mill wastewater (OMW) is produced as waste in olive oil extraction. With the purpose of treating this highly polluting waste, a number of experiments were conducted in a laboratory-scale bioreactor with the white rot fungus Phanerochaete flavido-alba ( P.flavido-alba). It is known that this fungus is capable of decolorizing OMW in static or semistatic cultures at Erlenmeyer scale and at 30 °C. The objective of this work was to prove that P. flavido-alba could decolorize OMW in submerged cultures and that it is capable of reducing OMW toxicity at room temperature (25 °C) and in a laboratory-scale bioreactor. In the experiments conducted, manganese peroxidase (MnP) and laccase enzymes were detected; however, unlike other studies, lignin peroxidase was not found to be present. Decoloration obtained after treatment was 70%. The reduction of aromatic compounds obtained was 51%, and the toxicity of the culture medium was reduced by up to 70%. We can therefore state that P.flavido-alba is capable of reducing important environmental parameters of industrial effluents and that prospects are positive for the use of this process at a larger scale, even when working at room temperature. [source] | ||||||||||