China
Africa
Explore chapters and articles related to this topic
Lignocellulosic Biomass Wastes to Bioenergy
Published in Amit Kumar, Chhotu Ram, Nanobiotechnology for Green Environment, 2021
Amit Kumar, Diwakar Aggarwal, Amit Kumar Bharti, Chhotu Ram
Lignin degradation is performed by white-rot fungi most effectively. Lignin peroxidases, manganese peroxidizes, and laccases are the major lignin-degrading enzymes that are produced by these fungi. The characteristics of these enzymes vary according to the microbial source. Lignin peroxidase is also known as ligninase. It is one of the most important enzymes involved in the degradation of lignin. Lignin peroxidase has high redox potential (700–1,400 mV) and it can degrade the compounds with high redox potential that are not oxidized by other enzymes. Lignin peroxide can oxidize both phenolic and non-phenolic compounds. It can cleave the recalcitrant non-phenolic units that comprise approximately 90% of lignin (Niladevi, 2009; Plácido and Capareda, 2015). Manganese peroxidase is another important enzyme produced by the lignin-degrading fungi. It is also a heme peroxidase and requires H2O2 for its activity. Manganese peroxidase has lower redox potential lignin peroxidase and generally, it does not oxidize non-phenolic lignin compounds. They are glycoproteins with a molecular weight between 38 and 62.5 kDa (Niladevi, 2009; Plácido and Capareda, 2015). Laccases are the multicopper oxidase enzyme, widely distributed in plants, fungi, and bacteria and have the ability to catalyze the oxidation of various phenolic and non-phenolic compounds as well as many environmental pollutants (Dwivedi et al., 2011).
*
Published in Eli Ruckenstein, Hangquan Li, Chong Cheng, Concentrated Emulsion Polymerization, 2019
Eli Ruckenstein, Xiao-Bai Wang
Phanerochaete chrysosporium belongs to a family of wood-rotting fungi. They excrete a highly effective extracellular oxidative enzyme (ligninase) capable of degrading not only lignin, but, being nonspecific, also a wide variety of compounds. Several articles1–6 have described the degradation of a wide spectrum of chlorocarbons and polycyclic aromatics, such as 1,1,1, trichloro-2,2 -bis(4-chlorophenynl) ethane (DDT) polychlorinated biphenyls, polychlorinated dibenzo-p-dioxins, lindane, and chlorinated alkanes.2–4
Potential of silver nanoparticles synthesized using low active mosquitocidal Lysinibacillus sphaericus as novel antimicrobial agents
Published in Preparative Biochemistry & Biotechnology, 2021
Magda A. El-Bendary, Mohamed Abdelraof, Maysa E. Moharam, Elmahdy M. Elmahdy, Mousa A. Allam
Bacterial filtrates showed nitrate reductase activity and perhaps the nitrate reductase plays an important role in the reduction of Ag+ into Ag0 and stabilizing them. It has been postulated that the enzymes secreted by microorganisms play an important role in the reduction of metal ions, leading to nanoparticles nucleation and growth.[38] The nitrate reductase enzyme is involved in the synthesis of AgNPs in Bacillus licheniformis as reported by Kalishwaralal et al.[39] Also, the ability of hydrogenase, laccase, and ligninase to synthesize metal nanoparticles were reported.[4,39,40] The synthesis of metal nanoparticles actually occurred by combinations of biomolecules that is produced by microorganisms such as proteins, amino acids, surfactants, vitamins, polysaccharides, etc.[40,41]
Synthesis, characterization and DFT aspects of some oxovanadium(IV) and manganese(II) complexes involving dehydroacetic acid and β-diketones
Published in Journal of Coordination Chemistry, 2018
Bashir Ahmad Malik, Jan Mohammad Mir
In a similar fashion, investigations on coordination chemistry of Mn have shown its important role in various biochemical systems [13–16]. The biological relevance of this metal stems from of its existence in enzymes, such as superoxide dismutase (Mn-SOD), catalase, Mn-ribonucleotide reductase, Mn-peroxidase, ligninase, the oxygen evolving center (OEC) of photosystem II (PS-II), Mn-thiosulfate oxidase and manganese-containing catechol dioxygenase. Various structural models of manganese enzymes have helped a lot in exploring various aspects of manganese chemistry on the basis of structural, electrochemical, and magnetic properties like vistas. This in turn has given rise in the development of manganese complexes with instant applications in magnetic and catalytic chemistry [17–19]. Moreover, it has been found that Mn plays an important role in growth and development of various tissues among both the plant as well as animal kingdoms [20].
Endocrine disrupting chemicals (EDCs): chemical fate, distribution, analytical methods and promising remediation strategies – a critical review
Published in Environmental Technology Reviews, 2023
Mridula Chaturvedi, Sam Joy, Rinkoo Devi Gupta, Sangeeta Pandey, Shashi Sharma
Lignin peroxidase (LiP) is heme-containing an extracellular enzyme, also known as ligninase, secreted by white rot fungi during secondary metabolism. LiPs have isoelectric point (pI) between 3.1 and 4.7 and optimum activities between pH (2–5) and temperature (35–55°C). The natural mediator that improves enzyme activities is veratyl alcohol. LiP does not need mediators as laccases to eliminate high redox-potential compounds but it involves hydrogen peroxide to initiate the catalysis. LiP activity is inhibited by hydroxyl amino-dinitrotoluene, EDTA, sodium azide and mercaptoethanol [147].