scholarly journals Genomics Analysis and Degradation Characteristics of Lignin by Streptomyces Thermocarboxydus Strain DF3-3

2021 ◽  
Author(s):  
Fangyun Tan ◽  
Jun Cheng ◽  
Yu Zhang ◽  
Xingfu Jiang ◽  
Yueqiu Liu
Keyword(s):  
Energy Conversion ◽  
Manganese Peroxidase ◽  
Metabolic Pathways ◽  
Lignin Degradation ◽  
Degradation Products ◽  
Degradation Mechanism ◽  
Biomass Energy ◽  
Raw Material ◽  
Gas Chromatography Mass Spectrometry ◽  
Degradation Intermediates

Abstract Background: Lignocellulose is an important raw material for biomass-to-energy conversion, and it exhibits a complex but inefficient degradation mechanism. Microbial degradation is promising due to its environmental adaptability and biochemical versatility, but the pathways used by microbes for lignin degradation have not been fully studied. Degradation intermediates and complex metabolic pathways require more study.Results: A novel actinomycete DF3-3, with the potential for lignin degradation, was screened and isolated. After morphological and molecular identification, DF3-3 was determined to be Streptomyces thermocarboxydus. The degradation of alkali lignin reached 31% within 15 days. Manganese peroxidase and laccase demonstrated their greatest activity levels, 1821.66 UL-1 and 1265.58 UL-1, respectively, on the sixth day. The highest lignin peroxidase activity was 480.33 UL-1 on the fourth day. A total of 19 lignin degradation intermediates were identified by gas chromatography-mass spectrometry (GC-MS), including 10 aromatic compounds. Genome sequencing and annotation identified 107 lignin-degrading enzyme-coding genes containing three core enzymatic systems for lignin depolymerization: laccases, peroxidases and manganese peroxidase. In total, 7 lignin metabolic pathways were predicted.Conclusions: Streptomyces thermocarboxydus strain DF3-3 has good lignin degradation ability. Degradation products and genomics analyses of DF3-3 show that it has a relatively complete lignin degradation pathway, including the β-ketoadipate pathway and peripheral reactions; gentisate pathway; anthranilate pathway; homogentisic pathway; and catabolic pathway for resorcinol. Two other pathways, the phenylacetate-CoA pathway and the 2,3-dihydroxyphenylpropionic acid pathway, are predicted based on genome data alone. This study provides the basis for future characterization of potential biotransformation enzyme systems for biomass energy conversion.

scholarly journals Model Analytical Development for Physical, Chemical, and Biological Characterization ofMomordica charantiaVegetable Drug

2016 ◽  
Vol 2016 ◽  
pp. 1-15 ◽  
Author(s):  
Deysiane Oliveira Brandão ◽  
Geovani Pereira Guimarães ◽  
Ravely Lucena Santos ◽  
Fernando José de Lima Ramos Júnior ◽  
Karla Monik Alves da Silva ◽  
...  
Keyword(s):  
Antimicrobial Activity ◽  
Analytical Methods ◽  
Degradation Products ◽  
Particle Surface ◽  
Momordica Charantia ◽  
Raw Material ◽  
Gas Chromatography Mass Spectrometry ◽  
Semiarid Region ◽  
Particle Sizes ◽  
Particle Surface Area

Momordica charantiais a species cultivated throughout the world and widely used in folk medicine, and its medicinal benefits are well documented, especially its pharmacological properties, including antimicrobial activities. Analytical methods have been used to aid in the characterization of compounds derived from plant drug extracts and their products. This paper developed a methodological model to evaluate the integrity of the vegetable drugM. charantiain different particle sizes, using different analytical methods.M. charantiawas collected in the semiarid region of Paraíba, Brazil. The herbal medicine raw material derived from the leaves and fruits in different particle sizes was analyzed using thermoanalytical techniques as thermogravimetry (TG) and differential thermal analysis (DTA), pyrolysis coupled to gas chromatography/mass spectrometry (PYR-GC/MS), and nuclear magnetic resonance (1H NMR), in addition to the determination of antimicrobial activity. The different particle surface area among the samples was differentiated by the techniques. DTA and TG were used for assessing thermal and kinetic parameters and PYR-GC/MS was used for degradation products chromatographic identification through the pyrograms. The infusions obtained from the fruit and leaves ofMomordica charantiapresented antimicrobial activity.

scholarly journals Lignin Degradation and Its Use in Signaling Development by the Coprophilous Ascomycete Podospora anserina

2020 ◽  
Vol 6 (4) ◽  
pp. 278
Author(s):  
Moussa Dicko ◽  
Roselyne Ferrari ◽  
Narumon Tangthirasunun ◽  
Valérie Gautier ◽  
Christophe Lalanne ◽  
...  
Keyword(s):  
Lignin Degradation ◽  
Degradation Products ◽  
Podospora Anserina ◽  
Food Sources ◽  
Gas Chromatography Mass Spectrometry ◽  
Oxygen Species ◽  
Pyrolysis Gas ◽  
Genetical Analysis ◽  
Miscanthus Giganteus ◽  
Wide Range

The filamentous fungus Podospora anserina is a good model to study the breakdown of lignocellulose, owing to its ease of culture and genetical analysis. Here, we show that the fungus is able to use a wide range of lignocellulosic materials as food sources. Using color assays, spectroscopy and pyrolysis–gas chromatography mass spectrometry, we confirm that this ascomycete is able to degrade lignin, primarily by hydrolyzing β–O-4 linkages, which facilitates its nutrient uptake. We show that the limited weight loss that is promoted when attacking Miscanthus giganteus is due to a developmental blockage rather than an inefficiency of its enzymes. Finally, we show that lignin, and, more generally, phenolics, including degradation products of lignin, greatly stimulate the growth and fertility of the fungus in liquid cultures. Analyses of the CATΔΔΔΔΔ mutant lacking all its catalases, pro-oxidants and antioxidants indicate that improved growth and fertility of the fungus is likely caused by augmented reactive oxygen species levels triggered by the presence of phenolics.

scholarly journals Photo-degradation ibuprofen by UV/H2O2 process: response surface analysis and degradation mechanism

2017 ◽  
Vol 75 (12) ◽  
pp. 2935-2951 ◽  
Author(s):  
Mingguo Peng ◽  
Huajie Li ◽  
Xu Kang ◽  
Erdeng Du ◽  
Dongdong Li
Keyword(s):  
Aqueous Solution ◽  
Response Surface ◽  
Ph Value ◽  
Uv Light ◽  
Degradation Products ◽  
Degradation Mechanism ◽  
Oh Radical ◽  
Initial Ph ◽  
Rsm Model ◽  
Degradation Intermediates

The removal of ibuprofen (IBP) in aqueous solution using UV/H2O2 process was evaluated. The response surface methodology (RSM) and Box–Behnken design were employed to investigate the effects of process parameters on IBP removal, including the initial IBP concentration, H2O2 dosage, UV light intensity, and initial pH value of solution. The RSM model developed herein fits well with the experiments, and provides a good insight into the OH radical irritated degradation mechanisms and kinetics. High resolution accurate mass spectrometry coupled with liquid chromatography was used to identify the degradation intermediates. A total of 23 degradation products were identified, including mono-hydroxylated products and dihydroxylated products. A series of OH radical-initiated reactions, including hydroxylation, dihydroxylation, decarboxylation, demethylation, ring break, lead to the final mineralization of IBP to CO2 and H2O. UV/H2O2 technology could be a promising technology for IBP removal in aqueous solution.

Electrochemical degradation of 2,5-dichloro-1,4-phenylenediamine by anodic oxidation

2013 ◽  
Vol 67 (10) ◽  
pp. 2177-2183 ◽  
Author(s):  
Weijing Liu ◽  
Yong Chen ◽  
Hongyi Li ◽  
Qin Zhong
Keyword(s):  
Electrochemical Oxidation ◽  
Anodic Oxidation ◽  
Degradation Kinetics ◽  
Degradation Mechanism ◽  
Combustion Efficiency ◽  
Gas Chromatography Mass Spectrometry ◽  
Cyclic Voltammograms ◽  
Electrochemical Degradation ◽  
Initial Ph ◽  
Degradation Intermediates

Electrochemical degradation of 2,5-dichloro-1,4-phenylenediamine (DP) in aqueous solution by anodic oxidation was investigated. Linear sweep voltammograms and cyclic voltammograms were studied. The influence of operating parameters on electrochemical oxidation of DP was studied as a function of the current density, initial pH, and initial concentration of DP. The degradation kinetics analysis indicated that the electrochemical degradation of DP followed a first-order reaction. The degradation intermediates during electrochemical oxidation were analyzed by UV–vis spectrophotometer, ionic chromatograph (IC), and gas chromatography/mass spectrometry (GC/MS). The combustion efficiency of DP at the anode was also estimated. The electrochemical oxidation of DP resulted in the release of NH4+ and Cl−. Based on these results, a degradation mechanism for electrochemical degradation of DP by anodic oxidation was proposed.

scholarly journals Transformation of Tetracycline by Manganese Peroxidase from Phanerochaete chrysosporium

Molecules ◽  
2021 ◽  
Vol 26 (22) ◽  
pp. 6803
Author(s):  
Xuemei Sun ◽  
Yifei Leng ◽  
Duanji Wan ◽  
Fengyi Chang ◽  
Yu Huang ◽  
...  
Keyword(s):  
Phanerochaete Chrysosporium ◽  
Manganese Peroxidase ◽  
Degradation Products ◽  
Degradation Mechanism ◽  
Transformation Products ◽  
Transformation Rate ◽  
Transformation Mechanism ◽  
Initial Concentration ◽  
Negative Impacts ◽  
High Level

The negative impacts on the ecosystem of antibiotic residues in the environment have become a global concern. However, little is known about the transformation mechanism of antibiotics by manganese peroxidase (MnP) from microorganisms. This work investigated the transformation characteristics, the antibacterial activity of byproducts, and the degradation mechanism of tetracycline (TC) by purified MnP from Phanerochaete chrysosporium. The results show that nitrogen-limited and high level of Mn2+ medium could obtain favorable MnP activity and inhibit the expression of lignin peroxidase by Phanerochaete chrysosporium. The purified MnP could transform 80% tetracycline in 3 h, and the threshold of reaction activator (H2O2) was about 0.045 mmol L−1. After the 3rd cyclic run, the transformation rate was almost identical at the low initial concentration of TC (77.05–88.47%), while it decreased when the initial concentration was higher (49.36–60.00%). The antimicrobial potency of the TC transformation products by MnP decreased throughout reaction time. We identified seven possible degradation products and then proposed a potential TC transformation pathway, which included demethylation, oxidation of the dimethyl amino, decarbonylation, hydroxylation, and oxidative dehydrogenation. These findings provide a novel comprehension of the role of MnP on the fate of antibiotics in nature and may develop a potential technology for tetracycline removal.

Systematical Characterization of Impurity Profiles in Daptomycin Raw Material by 2-Dimentional HPLC Tandem with MS Detector

2020 ◽  
Vol 16 ◽  
Author(s):  
Jin Li ◽  
Shang-Chen Yao ◽  
Li-Hui Yin ◽  
Chang-Qin Hu ◽  
Ming-Zhe Xu
Keyword(s):  
Thermodynamic Calculation ◽  
Degradation Products ◽  
Degradation Mechanism ◽  
Raw Material ◽  
Cyclic Lipopeptide ◽  
Mass Fragmentation ◽  
Positive Mode ◽  
On Line ◽  
First Time

Objective: To systematically characterize the impurity profile in Daptomycin raw material by 2 Dimensional LC/MSn. Method: The target impurity was separated by first Dimensional HPLC and enriched by a 500μl loop, then desalted using the on-line second Dimensional HPLC and analyzed by MS detector in positive mode. Their structures were characterized based on the degradation mechanism and mass fragmentation regularity of the cyclic lipopeptide, as well as the molecular thermodynamic calculation. Results: A total of 12 impurities were characterized in the raw material, including 6 degradation products; 8 impurities are reported for the first time. The mass fragmentation regularities of 2 β-isomers of Asp residue were summarized. Conclusion: The structures of impurities in Daptomycin raw material, especially for β-isomer impurities, could be rapidly identified by on-line 2 Dimensional LC/MSn method together with the molecular thermodynamic calculation.

scholarly journals Estimation of Ocean Thermal Energy Conversion Resources in the East of Malaysia

2020 ◽  
Vol 9 (1) ◽  
pp. 22
Author(s):  
Sathiabama T. T. Thirugnana ◽  
Abu Bakar Jaafar ◽  
Takeshi Yasunaga ◽  
Tsutomu Nakaoka ◽  
Yasuyuki Ikegami ◽  
...  
Keyword(s):  
Dissolved Oxygen ◽  
Energy Conversion ◽  
Thermal Energy ◽  
Biomass Energy ◽  
Relative Depth ◽  
Solar Pv ◽  
Ocean Thermal Energy Conversion ◽  
Thermal Energy Conversion ◽  
Oceanographic Data ◽  
Ocean Thermal Energy

The Malaysian Government has set a target of achieving 20% penetration of Renewable Energy (RE) in the energy mix spectrum by 2025. In order to get closer to the target, Ocean Thermal Energy Conversion (OTEC) aligned with solar PV, biogas and biomass energy sources must be evaluated and comprehended. Hybrid OTEC systems consisting of energy and water production are currently under research and validation. Therefore, for the construction of a commercial OTEC plant, 1 MW or 2.5 MW, the choice of a strategic location or potential site is vital. In this paper, oceanographic data such as seawater temperature, depth, salinity and dissolved oxygen obtained from the Japan Oceanographic Data Center (JODC) for Semporna, Tawau, Kudat, Pulau Layang-Layang and Pulau Kalumpang in Sabah, Malaysia, are reported. The RE available from the Exclusive Economic Zone (EEZ) on the coast of Sabah was estimated based on the JODC data obtained. There were no remarkable differences in temperatures between the five sites, which were reported as approximately 27 °C at the surface and 7 °C at depths below 600 m. The surface salinities below 100 m at those sites were slightly lower than the deeper waters, where the salinity increased up to approximately 34.5 PSU. Dissolved oxygen data from the Pulau Kalumpang site showed a slight increment to approximately 4.7 mL/L at depth intervals below 50 m, before declining steadily to approximately 1.7 mL/L along with the depth. The temperature-salinity profiles of the Malaysian sites were congruent with those of Palau, Kumejima and Okinawa, but not with that of Fiji, where the salinity profile showed a distinct variation at the relative depth (below 200 m). Estimates of RE using two different methods were used to prove the potential of OTEC in Malaysia.

Chemical characterization and in vitro fermentation ofBrassicastraw treated with the aerobic fungus,Trametes versicolor

2011 ◽  
Vol 91 (4) ◽  
pp. 695-702 ◽  
Author(s):  
J. E. Ramirez-Bribiesca ◽  
Y. Wang ◽  
L. Jin ◽  
T. Canam ◽  
J. R. Town ◽  
...  
Keyword(s):  
Mutant Strain ◽  
Trametes Versicolor ◽  
Lignin Degradation ◽  
Volatile Fatty Acids ◽  
Degradation Products ◽  
Chemical Characterization ◽  
Gas Production ◽  
In Vitro Fermentation ◽  
Lignin Degradation Products

Ramirez-Bribiesca, J. E., Wang, Y., Jin, L., Canam, T., Town, J. R., Tsang, A., Dumonceaux, T. J. and McAllister, T. A. 2011. Chemical characterization and in vitro fermentation of Brassica straw treated with the aerobic fungus, Trametes versicolor . Can. J. Anim. Sci. 91: 695–702. Brassica napus straw (BNS) was either not treated or was treated with two strains of Trametes versicolor; 52J (wild type) or m4D (a cellobiose dehydrogenase-deficient mutant) with four treatments: (i) untreated control (C-BNS), (ii) 52J (B-52J), (iii) m4D (B-m4D) or (iv) m4D+glucose (B-m4Dg). Glucose was provided to encourage growth of the mutant strain. All treatments with T. versicolor decreased (P<0.05) neutral-detergent fibre and increased (P<0.05) protein and the concentration of lignin degradation products in straw. Ergosterol was highest (P<0.05) in straw treated with B-52J, suggesting it generated the most fungal biomass. Insoluble lignin was reduced (P<0.05) in straw treated with B-52J and B-m4D, but not with B-m4Dg. Mannose and xylose concentration were generally higher (P<0.05) in straw treated with fungi, whereas glucose and galactose were lower as compared with C-BNS. The four treatments above were subsequently assessed in rumen in vitro fermentations, along with BNS treated with 2 mL g−1of 5 N NaOH. Concentrations of total volatile fatty acids after 24 and 48h were lower (P<0.05) in incubations that contained BNS treated with T. versicolor as compared with C-BNSor NaOH-treated BNS. Compared with C-BNS, in vitrodry matter disappearance and gas production were increased (P<0.05) by NaOH, but not by treatment with either strain of T. versicolor. Although treatment with T. versicolor did release more lignin degradation products, it did not appear to provide more degradable carbohydrate to in vitro rumen microbial populations, even when a mutant strain with compromised carbohydrate metabolism was utilized. Production of secondary compounds by the aerobic fungi may inhibit rumen microbial fermentation.

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