Computational Assessment of the Three-Dimensional Configuration of Dissolved Organic Matter Chromophores and Influence on Absorption Spectra

Enzymatic saccharification is a key step in the green conversion of lignocellulose to biofuels and other products. A key deficiency in common biocatalytic systems, such as Trichoderma reesei, is the insufficient presence of β-glucosidase (BGL). This study intended to develop an efficient process of BGL production as an enhancement to the T. reesei system. The authors investigated the process optimization of BGL by the mutant strain Aspergillus niger C112, which was previously developed in the authors’ laboratory. The culture medium and process (carbon, nitrogen, temperature, and pH) were optimized for cost-effective BGL production, which led to a maximum BGL activity of 8.91 ± 0.35 U/mL. In addition, the dynamics of the physio-chemical parameters (zeta potential and dissolved organic matter) of the process were studied and showed good correlations to the yield of BGL. Furthermore, a three-dimensional excitation-emission matrix fluorescence spectroscopy was successfully applied for analyzing the component, origin, and dynamics of dissolved organic matter, which contributed to a further understanding and optimization of BGL production.

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Characterization of dissolved organic matter in a submerged membrane bioreactor by using three-dimensional excitation and emission matrix fluorescence spectroscopy

Water Research ◽

10.1016/j.watres.2008.12.033 ◽

2009 ◽

Vol 43 (6) ◽

pp. 1533-1540 ◽

Cited By ~ 293

Author(s):

Zhiwei Wang ◽

Zhichao Wu ◽

Shujuan Tang

Keyword(s):

Organic Matter ◽

Fluorescence Spectroscopy ◽

Dissolved Organic Matter ◽

Membrane Bioreactor ◽

Three Dimensional ◽

Submerged Membrane Bioreactor ◽

Excitation And Emission Matrix

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Characteristics of dissolved organic matter in a water purification plant and distribution pipes

MATEC Web of Conferences ◽

10.1051/matecconf/201928003007 ◽

2019 ◽

Vol 280 ◽

pp. 03007 ◽

Cited By ~ 1

Author(s):

Toshiro Yamada ◽

Maulana Yusup Rosadi ◽

Hudori ◽

Yukitaka Suzuki ◽

Eri Ito ◽

...

Keyword(s):

Molecular Weight ◽

Organic Matter ◽

Water Treatment ◽

Dissolved Organic Matter ◽

Three Dimensional ◽

Quality Parameters ◽

Raw Water ◽

Treatment Unit ◽

Treatment Processes ◽

Doc Concentration

Dissolved organic matter (DOM) needs to be characterized todetermine the ability of a water treatment unit to reduce organic matter andits relationship to the levels of chlorine required for disinfection. Weinvestigated water quality parameters, including DOM, in a waterpurification plant and distribution pipes located in central Japan. Thedissolved organic carbon (DOC) concentration decreased from 0.73 mg/Lin raw water to 0.50 mg/L in purified water by conventional treatmentprocesses. The DOC of purified water decreased slightly in the pipesdownstream of the plant. The three-dimensional excitation-emission matrixfluorescence spectra showed some specific peaks for humic-like substancesand protein-like substances in all water samples, and the compositions ofDOM in purified water were close to those in raw water. However, therewas a peak of protein-like substances in purified and returned water, whichwas not observed for raw water. The fluorescence intensities of humic-likesubstances in purified water decreased downstream of the plant, while thefluorescence intensities of protein-like substances increased in the pipes. The measured molecular weight distributions of DOM in water presentedsome specific peaks, and DOM with a smaller molecular weight was noteasily removed by water treatment processes. There were positiverelationships between decreases in the intensities of some peaks andresidual chlorine decay.

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Three-dimensional excitation-emission matrix fluorescence spectroscopy and fractions of dissolved organic matter change in landfill leachate by biological treatment

Environmental Science and Pollution Research ◽

10.1007/s11356-015-5226-8 ◽

2015 ◽

Vol 23 (1) ◽

pp. 793-799 ◽

Cited By ~ 16

Author(s):

Yanrui Cui ◽

Qing Wu ◽

Mengsi Yang ◽

Fengling Cui

Keyword(s):

Organic Matter ◽

Fluorescence Spectroscopy ◽

Dissolved Organic Matter ◽

Landfill Leachate ◽

Biological Treatment ◽

Three Dimensional ◽

Excitation Emission Matrix

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Fluorescence analysis allows to predict the oxidative capacity of humic quinones in dissolved organic matter: implication for pollutant degradation

Environmental Chemistry Letters ◽

10.1007/s10311-020-01137-z ◽

2020 ◽

Author(s):

Davide Palma ◽

Edith Parlanti ◽

Mahaut Sourzac ◽

Olivier Voldoire ◽

Aude Beauger ◽

...

Keyword(s):

Organic Matter ◽

Dissolved Organic Matter ◽

Water Samples ◽

Three Dimensional ◽

Complex Mixture ◽

Fluorescence Analysis ◽

Oxidative Capacity ◽

Reactive Species ◽

Solar Light ◽

Pollutant Degradation

AbstractDissolved organic matter (DOM) controls the degradation and sequestration of aquatic pollutants and, in turn, water quality. In particular, pollutant degradation is performed by oxidant species that are generated by exposure of DOM to solar light, yet, since DOM is a very complex mixture of poorly known substances, the relationships between potential oxidant precursors in DOM and their oxydative capacity is poorly known. Here, we hypothesized that production of oxidant species could be predicted using fluorescence analysis. We analysed water samples from an alluvial plain by fluorescence spectroscopy; the three-dimensional spectra were then decomposed into seven individual components using a multi-way algorithm. Components include a protein-like fluorophore, e.g. tryptophan-like and tyrosine-like, three humic fluorophores, 2-naphthoxyacetic acid, and a by-product. We compared component levels with the ability of water samples to generate reactive species under solar light. The results show a strong correlation between reactive species production and the intensity of two humic-like fluorophores assigned to reduced quinones. Monitoring these fluorophores should thus allow to predict the ability of DOM degradation of pollutants in surface waters.

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Seasonal and spatial variations in characteristics of Lake Biwa dissolved organic matter: sorption of pyrene and its derivatives and fluorescence properties

Water Science & Technology ◽

10.2166/wst.2008.743 ◽

2008 ◽

Vol 58 (8) ◽

pp. 1609-1614

Author(s):

T. Kusakabe ◽

K. Ikeda ◽

Y. Shimizu ◽

S. Higashi ◽

Y. Kawabata ◽

...

Keyword(s):

Organic Matter ◽

Dissolved Organic Matter ◽

Lake Biwa ◽

Vertical Mixing ◽

Three Dimensional ◽

Spatial Variations ◽

Fluorescence Properties ◽

Sorption Coefficient ◽

Suwannee River Fulvic Acid ◽

Seasonal And Spatial Variations

The objectives of this research were to investigate seasonal and spatial variations in (1) sorption of pyrene and its derivatives onto dissolved organic matter (DOM) and (2) fluorescence properties of DOM in Lake Biwa, Japan. In the case of pyrene, sorption coefficient (Kdoc) of Lake Biwa DOM seasonally changed from 1,200 to 3,800 L/kgC. Vertical distribution of Kdoc was affected by thermocline formation in summer, while it was uniformly distributed as a result of vertical mixing in winter. Functional groups affected sorption of pyrene onto Lake Biwa DOM in different manner from that onto Suwannee River fulvic acid. Three-dimensional excitation emission matrices (3D-EEMs) fluorescence spectroscopy was applied to characterize Lake Biwa DOMs and indicated the existence of at least two fluorophores. The two major peaks at Ex230/Em300 and Ex230/Em425 originated from protein-like and fulvic/humic-like substances, respectively. The peak at Ex230/Em300 showed the maximum fluorescence intensity at a depth of 5 m and could be affected by stratification of the water column in summer. On the other hand, the peak at Ex230/Em425 showed similar profiles both in summer and in winter. These results demonstrably showed that sorption of micropollutants and fluorescence properties of Lake Biwa DOMs were seasonally and spatially varied.

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