scholarly journals Production of Ligninolytic Enzymes by Coptotermes curvignathus Gut Bacteria

2019 ◽  
Vol 23 (1) ◽  
pp. 111-121 ◽  
Author(s):  
Fadilah Ayeronfe ◽  
Angzzas Kassim ◽  
Patricia Hung ◽  
Nadiah Ishak ◽  
Sharfina Syarifah ◽  
...  
Keyword(s):  
Lignocellulosic Biomass ◽  
Lignin Degradation ◽  
Laccase Activity ◽  
Ligninolytic Enzymes ◽  
Maximal Activity ◽  
Kraft Lignin ◽  
Bacterial Strains ◽  
Materials Synthesis ◽  
Culture Supernatants ◽  
Maximum Utilization

Abstract Maximum utilization of lignocellulosic biomass is contingent upon degrading the recalcitrant lignin polymer. Conventional methods employed in delignification require high inputs of energy and chemicals, resulting in the release of highly toxic effluents. The ability of gut flora of Coptotermes curvignathus in lignin degradation was investigated in this study. Production of ligninolytic enzymes was done in an aerated submerged fermentation system with kraft lignin as sole carbon source. The degradation experiment was carried out for 7 days at 30 °C, pH 7. Three potential lignin degraders identified as Bacillus sp., Lysinibacillus sp. and Acinetobacter sp. were successfully isolated. The bacterial growth and secretion of extracellular ligninolytic enzymes confirmed metabolism of kraft lignin by the identified strains. Lysinibacillus sp., a novel lignin degrader showed highest manganese peroxidase (76.36 ± 15.74 U/L) and laccase activity (70.67 ± 16.82 U/L) after 7 and 6 days of incubation respectively, while maximal activity of lignin peroxidase (262.49 ± 0.92 U/L) was recorded after 7 days in culture supernatants of Bacillus sp. With respect to the activity of the secreted enzymes, the lignin degrading potential of these bacterial strains can be explored in the valorisations of lignocellulosic biomass in industrial processes such as pulping, bioethanol production, fine chemicals and materials synthesis.

Enhanced Delignification of Lignocellulosic Biomass by Recombinant Fungus Phanerochaete chrysosporium Overexpressing Laccases and Peroxidases

2018 ◽  
Vol 28 (1) ◽  
pp. 1-13 ◽  
Author(s):  
Nancy Coconi Linares ◽  
Francisco Fernández ◽  
Achim M. Loske ◽  
Miguel A. Gómez-Lim
Keyword(s):  
Lignocellulosic Biomass ◽  
Phanerochaete Chrysosporium ◽  
Wheat Bran ◽  
Enzyme Production ◽  
Lignin Degradation ◽  
Laccase Activity ◽  
Ligninolytic Enzymes ◽  
Lignocellulose Degradation ◽  
Total Phenolic ◽  
Recombinant Strains

Ligninolytic enzyme production and lignin degradation are typically the rate-limiting steps in the biofuel industry. To improve the efficiency of simultaneous bio-delignification and enzyme production, <i>Phanerochaete chrysosporium</i> was transformed by shock wave-induced acoustic cavitation to co-overexpress 3 peroxidases and 1 laccase and test it on the degradation of sugarcane bagasse and wheat bran. Lignin depolymerization was enhanced by up to 25% in the presence of recombinant fungi in comparison with the wild-type strain. Sugar release on lignocellulose was 2- to 6-fold higher by recombinant fungi as compared with the control. Wheat bran ostensibly stimulated the production of ligninolytic enzymes. The highest peroxidase activity from the recombinant strains was 2.6-fold higher, whereas the increase in laccase activity was 4-fold higher in comparison to the control. The improvement of lignin degradation was directly proportional to the highest peroxidase and laccase activity. Because various phenolic compounds released during lignocellulose degradation have proven to be toxic to cells and to inhibit enzyme activity, a significant reduction (over 40%) of the total phenolic content in the samples treated with recombinant strains was observed. To our knowledge, this is the first report that engineering <i>P. chrysosporium</i> enhances<i></i> biodegradation of lignocellulosic biomass.

Degradation of natural and Kraft lignins by the microflora of soil and water

1977 ◽  
Vol 23 (4) ◽  
pp. 434-440 ◽  
Author(s):  
Don L. Crawford ◽  
Suellen Floyd ◽  
Anthony L. Pometto III ◽  
Ronald L. Crawford
Keyword(s):  
Molecular Weight ◽  
Microbial Degradation ◽  
Lignin Degradation ◽  
Kraft Lignin ◽  
Lignin Biodegradation ◽  
Incubation Periods ◽  
Molecular Weight Fractions ◽  
Soil And Water ◽  
Different Molecular Weight ◽  
Microbial Attack

The comparative rates of microbial degradation 14C-lignin-labeled lignocelluloses and 14C-Kraft lignins were investigated using selected soil and water samples as sources of microorganisms. Natural lignocelluloses containing 14C primarily in their lignin components were prepared by feeding plants uniformly labeled L-[14C]phenylalanine through their cut stems. 14C-Kraft lignins were prepared by pulping lignin-labeled lignocelluloses. Rates of lignin biodegradation were determined by monitoring 14CO2 evolution from incubation mixtures over incubation periods of up to 1000 h. Observed rates of lignin degradation were slow in all cases. Kraft lignins appeared more resistant to microbial attack than natural lignins, even though they were decomposed more rapidly during the first 100–200 h of incubation. Similar degradation patterns were observed in both soil and water. Individual samples, however, varied greatly in their overall rates of degradation of either lignin type. A Kraft-lignin preparation was separated into a variety of molecular weight fractions by column chromatography on LH-20 Sephadex and the biodegradability of the different molecular weight fractions determined. The lower molecular weight fractions of the Kraft lignin were decomposed at a significantly faster rate by the microflora of soil than were the fractions of higher molecular weight.

scholarly journals Effect of Lignin-Containing Media on Growth of Medicinal Mushroom Lentinula Edodes

2017 ◽  
Vol 71 (1-2) ◽  
pp. 38-42
Author(s):  
Nataļja Matjuškova ◽  
Laura Okmane ◽  
Dzintra Zaļā ◽  
Linda Rozenfelde ◽  
Māris Puķe ◽  
...  
Keyword(s):  
Wheat Straw ◽  
Nutrient Medium ◽  
Laccase Activity ◽  
Biomass Yield ◽  
Lentinula Edodes ◽  
Reference Conditions ◽  
Kraft Lignin ◽  
Mushroom Cultivation ◽  
Cultivation Medium ◽  
Solid Nutrient Medium

Abstract The effect of lignocellulose and lignin on growth of mycelium of mushroom Lentinula edodes and laccase activity in cultivation medium was studied. It was shown that cultivation of L. edodes mycelium in liquid nutrient medium with addition of 0.25-0.5% of kraft lignin increased mycelium biomass yield approximately two times compared with reference conditions without addition of lignin. Similar results were obtained in experiments in which 0.5% lignocellulose that remained after obtaining furfural, and 0.5% lignin that remained after obtaining furfural and glucose from wheat straw, were added to the nutrient medium. This effect was greater in the conditions of cultivation with good aeration, compared with static culture. Laccase activity in medium increased after addition of wheat straw lignocellulose or lignin only in the case of mycelium cultivation with aeration. In the case of mushroom cultivation on solid nutrient medium, addition of wheat straw lignocellulose and lignin promoted growth of mycelium only during the first 7 days of cultivation.

A novel method for improving laccase activity by immobilization onto copper ferrite nanoparticles for lignin degradation

2020 ◽  
Vol 152 ◽  
pp. 1098-1107 ◽  
Author(s):  
Kirupa Sankar Muthuvelu ◽  
Ravikumar Rajarathinam ◽  
Roselin Nivetha Selvaraj ◽  
Vignesh Babu Rajendren
Keyword(s):  
Lignin Degradation ◽  
Laccase Activity ◽  
Ferrite Nanoparticles ◽  
Copper Ferrite ◽  
Novel Method

Isolation and Characterization of a Novel Bacillus subtilis WD23 Exhibiting Laccase Activity from Forest Soil

2010 ◽  
Vol 113-116 ◽  
pp. 725-729 ◽  
Author(s):  
Chun Lei Wang ◽  
Min Zhao ◽  
De Bin Li ◽  
Dai Zong Cui ◽  
Hong Yi Yang ◽  
...  
Keyword(s):  
Bacillus Subtilis ◽  
Forest Soil ◽  
Half Life ◽  
Laccase Activity ◽  
Methyl Violet ◽  
Bacterial Strains ◽  
Biochemical Tests ◽  
Alizarin Red ◽  
Optimum Growth Temperature ◽  
Isolation And Characterization

The strain Bacillus sp. WD23 exhibiting laccase activity was screened from forest soil. The M9 medium containing Cu2+ was used for enriching and isolating bacterial strains capable of oxidizing syringaldazine (SGZ). One isolated strain was identified as Bacillus subtilis WD23 based on the results of physiological and biochemical tests and 16S rDNA sequence analysis. The strain WD23 could grow at temperatures ranging from 20 to 55°C and showed optimum growth temperature and pH at 25°C and 7.0, respectively. The sporulation rate of the strain clearly correlated well with the laccase activity. The temperature half-life of the spore laccase was 2.5 h at 80°C and the pH half-life was 15 d at pH 9.0. Its spore laccase could decolorized 50~90% of Remazol brilliant blue R (RBBR), alizarin red, congo red, methyl orange and methyl violet, which suggests the potential application of spore laccase in dyestuff treatment.

Enhancement of lignin degradation and laccase activity in Pleurotus ostreatus by cotton stalk extract

1998 ◽  
Vol 44 (7) ◽  
pp. 676-680 ◽  
Author(s):  
Orly Ardon ◽  
Zohar Kerem ◽  
Yitzhak Hadar
Keyword(s):  
Oxygen Consumption ◽  
Pleurotus Ostreatus ◽  
Lignin Degradation ◽  
Laccase Activity ◽  
White Rot ◽  
White Rot Fungus ◽  
Lignin Biodegradation ◽  
Cotton Stalk ◽  
Fermentation System ◽  
Uv Visible

The white rot fungus Pleurotus ostreatus was grown in a chemically defined solid state fermentation system amended with cotton stalk extract (CSE).Treated cultures exhibited increased laccase activity as well as enhanced lignin mineralization. Mineralization of [14C]lignin initialized 4 days earlier in CSE-supplemented cultures than in control cultures. Total mineralization in the first 16 days was 15% in the CSE-treated cultures, compared with only 7% in the controls. Cotton stalk extract also contained compounds that serve as substrates for laccase purified from P. ostreatus as shown by oxygen consumption, as well as changes in the UV–visible spectrum.Key words: cotton, Pleurotusostreatus, white rot, laccase, lignin biodegradation.

scholarly journals Decolourisation Capabilities of Ligninolytic Enzymes Produced byMarasmius cladophyllusUMAS MS8 on Remazol Brilliant Blue R and Other Azo Dyes

2017 ◽  
Vol 2017 ◽  
pp. 1-8 ◽  
Author(s):  
Ngieng Ngui Sing ◽  
Ahmad Husaini ◽  
Azham Zulkharnain ◽  
Hairul Azman Roslan
Keyword(s):  
Azo Dyes ◽  
Culture Medium ◽  
Laccase Activity ◽  
Dye Degradation ◽  
Ligninolytic Enzymes ◽  
Brilliant Blue ◽  
Remazol Brilliant Blue R ◽  
Orange G ◽  
Dye Decolourisation

Marasmius cladophylluswas examined for its ability to degradatively decolourise the recalcitrant dye Remazol Brilliant Blue R (RBBR) and screened for the production of ligninolytic enzymes using specific substrates. Monitoring dye decolourisation by the decrease in absorbance ratio ofA592/A500shows that the decolourisation of RBBR dye was associated with the dye degradation.Marasmius cladophyllusproduces laccase and lignin peroxidase in glucose minimal liquid medium containing RBBR. Both enzyme activities were increased, with laccase activity recorded 70 times higher reaching up to 390 U L−1on day 12. Further in vitro RBBR dye decolourisation using the culture medium shows that laccase activity was correlated with the dye decolourisation. Fresh RBBR dye continuously supplemented into the decolourised culture medium was further decolourised much faster in the subsequent round of the RBBR dye decolourisation. In vitro dye decolourisation using the crude laccase not only decolourised 76% of RBBR dye in just 19 hours but also decolourised 54% of Orange G and 33% of Congo red at the same period of time without the use of any exogenous mediator. This rapid dye decolourisation ability of the enzymes produced byM. cladophyllusthus suggested its possible application in the bioremediation of dye containing wastewater.

scholarly journals Transcriptomics analysis reveals the high biodegradation efficiency of white-rot fungus Phanerochaete sordida YK-624 on native lignin

2020 ◽  
Author(s):  
Jianqiao Wang ◽  
Tomohiro Suzuki ◽  
Hideo Dohra ◽  
Toshio Mori ◽  
Hirokazu Kawagishi ◽  
...  
Keyword(s):  
Gene Expression ◽  
Lignin Degradation ◽  
Ligninolytic Enzymes ◽  
Organic Matrix ◽  
Tca Cycle ◽  
Underlying Mechanism ◽  
White Rot ◽  
White Rot Fungus ◽  
Lignin Biodegradation ◽  
Phanerochaete Sordida

Abstract Background Lignocellulosic biomass is an organic matrix composed of cellulose, hemicellulose, and lignin. In nature, lignin degradation by basidiomycetes is the key step in lignocellulose decay. The white-rot fungus Phanerochaete sordida YK-624 (YK-624) has been extensively studied due to its high lignin degradation ability. In our previous study, it was demonstrated that YK-624 can secrete lignin peroxidase and manganese peroxidase for lignin degradation. However, the underlying mechanism for lignin degradation by YK-624 remains unknown.Results Here, we analyzed YK-624 gene expression following growth under ligninolytic and nonligninolytic conditions and compared the differentially expressed genes in YK-624 to those in the model white-rot fungus P. chrysosporium by next-generation sequencing. More ligninolytic enzymes and lignin-degrading auxiliary enzymes were upregulated in YK-624. This might explain the high degradation efficiency of YK-624. In addition, the genes involved in energy metabolism pathways, such as the TCA cycle, oxidative phosphorylation, lipid metabolism, carbon metabolism and glycolysis, were upregulated under ligninolytic conditions in YK-624.Conclusions In the present study, the first differential gene expression analysis of YK-624 under ligninolytic and nonligninolytic conditions was reported. The results obtained in this study indicated that YK-624 produces more energy- and lignin-degrading enzymes for more efficient lignin biodegradation.

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