Comparison of different valent iron on anaerobic sludge digestion: Focusing on oxidation reduction potential, dissolved organic nitrogen and microbial community

2021 ◽  
Vol 16 (6) ◽  
Author(s):  
Zecong Yu ◽  
Keke Xiao ◽  
Yuwei Zhu ◽  
Mei Sun ◽  
Sha Liang ◽  
...  
Keyword(s):  
Microbial Community ◽  
Dissolved Organic Nitrogen ◽  
Organic Nitrogen ◽  
Reduction Potential ◽  
Anaerobic Sludge ◽  
Sludge Digestion ◽  
Oxidation Reduction ◽  
Oxidation Reduction Potential ◽  
Anaerobic Sludge Digestion

scholarly journals Restoration and Purification of Dissolved Organic Nitrogen by Bacteria and Phytoremediation in Shallow Eutrophic Lakes Sediments

2018 ◽  
Vol 38 ◽  
pp. 01027
Author(s):  
Xin Li ◽  
Yi Yue
Keyword(s):  
Amino Acid ◽  
Microbial Activity ◽  
Dissolved Organic Nitrogen ◽  
Organic Nitrogen ◽  
Potential Temperature ◽  
Eutrophic Lakes ◽  
Oxidation Reduction ◽  
Oxidation Reduction Potential ◽  
Nitrogen Loadings

Endogenous organic nitrogen loadings in lake sediments have increased with human activity in recent decades. A 6-month field study from two disparate shallow eutrophic lakes could partly reveal these issues by analysing seasonal variations of biodegradation and phytoremediation in the sediment. This paper describes the relationship between oxidation reduction potential, temperature, microbial activity and phytoremediation in nitrogen cycling by calculation degradative index of dissolved organic nitrogen and amino acid decomposition. The index was being positive in winter and negative in summer while closely positive correlated with biodegradation. Our analysis revealed that rather than anoxic condition, biomass is the primary factor to dissolved organic nitrogen distribution and decomposition. Some major amino acids statistics also confirm the above view. The comparisons of organic nitrogen and amino acid in abundance and seasons in situ provides that demonstrated plants cue important for nitrogen removal by their roots adsorption and immobilization. In conclusion, enhanced microbial activity and phytoremediation with the seasons will reduce the endogenous nitrogen loadings by the coupled mineralization and diagenetic process.

The Bioleaching Characteristics of Chalcopyrite with Different Genetic Types

2013 ◽  
Vol 825 ◽  
pp. 443-446 ◽  
Author(s):  
Jing Bai ◽  
Jiang Kang Wen ◽  
Song Tao Huang ◽  
Biao Wu ◽  
Bo Wei Chen
Keyword(s):  
Microbial Community ◽  
Reduction Potential ◽  
Extraction Yield ◽  
Genetic Type ◽  
Copper Extraction ◽  
Genetic Types ◽  
Oxidation Reduction ◽  
Oxidation Reduction Potential

The copper extraction yield from thermophilic bioleaching of chalcopyrite depends on temperature, pH, and the oxidation-reduction potential (ORP), the activity of the thermophile used, as well as on the different genetic type of the chalcopyrite used. The bioleaching characteristics of chalcopyrite from marine volcanic type and porphyry type, and the influence of genetic type on microbial community were studied. The results indicated that the bioleaching of chalcopyrite is controlled by the ORP rather than by the pH. The thermophiles composition of marine volcanic type bioleaching wasMetallosphaeracuprinaandSulfobus spHB59.Metallosphaeracuprinawas the dominate bacteria during porphyry chalcopyrite bioleaching. The different leachability between marine volcanic type and porphyry type is attributed to their nature which caused by genetic type.

scholarly journals On the Elucidation of the pH Dependence of the Oxidation-Reduction Potential of Cytochrome c at Alkaline pH

1966 ◽  
Vol 241 (18) ◽  
pp. 4180-4185
Author(s):  
Karl G. Brandt ◽  
Paul C. Parks ◽  
Georg H. Czerlinski ◽  
George P. Hess
Keyword(s):  
Cytochrome C ◽  
Reduction Potential ◽  
Ph Dependence ◽  
Alkaline Ph ◽  
Oxidation Reduction ◽  
Oxidation Reduction Potential

scholarly journals In situ measurements of oxidation–reduction potential and hydrogen peroxide concentration as tools for revealing LPMO inactivation during enzymatic saccharification of cellulose

2021 ◽  
Vol 14 (1) ◽  
Author(s):  
Adnan Kadić ◽  
Anikó Várnai ◽  
Vincent G. H. Eijsink ◽  
Svein Jarle Horn ◽  
Gunnar Lidén
Keyword(s):  
Reduction Potential ◽  
Enzymatic Saccharification ◽  
The State ◽  
Enzyme Inactivation ◽  
Ex Situ ◽  
Process Economics ◽  
Complete Inactivation ◽  
Oxidation Reduction ◽  
Oxidation Reduction Potential

Abstract Background Biochemical conversion of lignocellulosic biomass to simple sugars at commercial scale is hampered by the high cost of saccharifying enzymes. Lytic polysaccharide monooxygenases (LPMOs) may hold the key to overcome economic barriers. Recent studies have shown that controlled activation of LPMOs by a continuous H2O2 supply can boost saccharification yields, while overdosing H2O2 may lead to enzyme inactivation and reduce overall sugar yields. While following LPMO action by ex situ analysis of LPMO products confirms enzyme inactivation, currently no preventive measures are available to intervene before complete inactivation. Results Here, we carried out enzymatic saccharification of the model cellulose Avicel with an LPMO-containing enzyme preparation (Cellic CTec3) and H2O2 feed at 1 L bioreactor scale and followed the oxidation–reduction potential and H2O2 concentration in situ with corresponding electrode probes. The rate of oxidation of the reductant as well as the estimation of the amount of H2O2 consumed by LPMOs indicate that, in addition to oxidative depolymerization of cellulose, LPMOs consume H2O2 in a futile non-catalytic cycle, and that inactivation of LPMOs happens gradually and starts long before the accumulation of LPMO-generated oxidative products comes to a halt. Conclusion Our results indicate that, in this model system, the collapse of the LPMO-catalyzed reaction may be predicted by the rate of oxidation of the reductant, the accumulation of H2O2 in the reactor or, indirectly, by a clear increase in the oxidation–reduction potential. Being able to monitor the state of the LPMO activity in situ may help maximizing the benefit of LPMO action during saccharification. Overcoming enzyme inactivation could allow improving overall saccharification yields beyond the state of the art while lowering LPMO and, potentially, cellulase loads, both of which would have beneficial consequences on process economics.

Sign in / Sign up

Export Citation Format

Share Document