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Ibrahim H. Mondal - One of the best experts on this subject based on the ideXlab platform.
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Control of the crystal structure of Microbial Cellulose during nascent stage
Journal of Applied Polymer Science, 2020Co-Authors: Ibrahim H. MondalAbstract:The structure of the product, from an Acetobacter culture in the presence of Fluorescent Brightener, Direct Red 28, and Direct Blue 1, 14, 15 and 53, characterized by an X-ray diffractormeter is a crystalline complex. On the other hand, solid-state 13C-NMR spectroscopy reveals that the product is noncrystalline. However, the X-ray result of the product sample suggests that the dye molecule is included in the form of a monolayer between the Cellulose sheets in the complex corresponding to the (11¯0) plane of Microbial Cellulose. But the Celluloses regenerated from the Fluorescent Brightener product, the Direct Red 28 product, and the rest of the dye products are Celluloses I, IV, and II, respectively. More specifically, the 13C-NMR spectra revealed that the crystal types of Cellulose from the Fluorescent Brightener and Direct Red 28 products are Iβ and IVI, respectively. Thus, the crystal structure of the product and the regenerated Cellulose depends mainly on the position and number of the sulfonate groups in a direct dye and the interactions of the dye with the noncrystalline Microbial Cellulose in the nascent stage. The conformation and arrangement of the nascent Cellulose chain changes when a direct dye adheres to it. © 2000 John Wiley & Sons, Inc. J Appl Polym Sci 79: 1726–1734, 2001
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Mechanism of structure formation of Microbial Cellulose during nascent stage
Cellulose, 2013Co-Authors: Ibrahim H. MondalAbstract:The structure of Microbial Cellulose (MC) produced by Acetobacter xylinum was studied in presence of Fluorescent Brightener, Direct Blue 1, 14, 15, 53, Direct Red 28, 75 and 79, as probe. X-ray diffraction pattern of the product showed that it was a crystalline complex of dye and Cellulose. The product has the structure in which the monomolecular layer of the dye molecule is included between the Cellulose sheets corresponding to the (\( 1\bar{1}0 \)) planes of Microbial Cellulose. As a result of dye inclusion, d-spacing of lower angle plane (100) of products becomes 8.0–8.8 A instead of 6.1 A of MC. The d-spacing for the higher angle plane must be (010) plane due to stronger van der Waals forces between the pyranose rings which reduced 5.3 A space of (110) plane of MC to 3.9–4.5 A in the product. However, Cellulose regenerated from FB, DR28 products was Cellulose I and IV, respectively, and that from each DB1, 14, 15, 53, DR75 and 79 products was Cellulose II. Solid state 13C NMR and deuteration-IR showed the product was non-crystalline which was contrasted to X-ray results. The regenerated Celluloses were Cellulose Iβ, IVI and II, respectively. Thus the structure of the product depends on the characteristics of dye which affects the conformation of Cellulose at the nascent stage by the direct interaction with Cellulose chains. The different regenerated Celluloses as well as different fine structure in the same Cellulose allomorph were produced depending mainly on number and position of the sulfonate groups in the dye.
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Influence of substitution of direct dye having biphenylenebis(azo) skeletal structure on nascent Cellulose produced by acetobacter xylinum [II]
Journal of Applied Polymer Science, 1999Co-Authors: Ibrahim H. MondalAbstract:The influence of Direct Blue 14 and 53 dyes, both having biphenylenebis(azo) skeletal structure but different sulfonate groups substitution on the structure of the nascent Microbial Cellulose was examined. The product obtained from the Acetobacter culture in the presence of each dye is a characteristic dye–Cellulose complex, and the dye molecule is included between the Cellulose sheets in the complex corresponding to the (110) plane of Microbial Cellulose. Due to the inclusion of dyes between the Cellulose sheets through hydrogen bonding or van der Waals forces, the hydrogen bonding between Cellulose chains of Microbial Cellulose is hindered. The different position of sulfonate groups has no major influence on the two products except on the uniplanar orientation of the product. Celluloses regenerated from both products are Cellulose II, but their fine structures are different from each other. © 1999 John Wiley & Sons, Inc. J Appl Polym Sci 71: 1007–1015, 1999
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Structure of Nascent Microbial Cellulose III. Different Influence of Direct Red 75 and 79 on Nascent Microbial Cellulose
Polymer Journal, 1998Co-Authors: Ibrahim H. MondalAbstract:The influence of Direct Red 75 and 79 having the same ureylenebis(naphthylazo)benzene skeletal structure on the nascent structure of Microbial Cellulose was examined. Each product obtained from Acetobacter-culture in the presence of Direct Red 75 or Direct Red 79 is a crystalline complex in which the monolayer of a dye is included between the Cellulose sheets corresponding to the (110) plane of Microbial Cellulose. Cellulose regenerated from each product forms Cellulose II. Although the substituent groups in the skeletal structure of both the dyes are not the same, there is no different interactions on the nascent structure of Microbial Cellulose. Due to the ureylene group on the skeletal structure of dye, stronger hydrogen bonding is occurred between the dye and Cellulose in the product. The ureylene group affects stable hydrogen bonding in the Cellulose regenerated from Direct Red 75 and Direct Red 79 products.
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Structure of Nascent Microbial Cellulose II. Effects of Methyl and Methoxy Groups of Direct Blue 14 and 15 on Nascent Microbial Cellulose
Polymer Journal, 1998Co-Authors: Ibrahim H. MondalAbstract:The effects of methyl and methoxy groups in Direct Blue 1 and Direct Blue 53 on the structure of nascent Microbial Cellulose were characterized by X-ray, solid state 13C NMR and deuteration-IR measurements. There were no other differences between these two direct dyes, except methyl and methoxy groups. The product obtained from Acetobacter-culture in the presence of each Direct Blue 1 and Direct Blue 53 is a crystalline complex composed of a dye and Cellulose, and the product has a structure in which the dye molecule is between the Cellulose sheets corresponding to the (100) plane of the complex, i.e., (110) planes of Microbial Cellulose. Celluloses regenerated from both products form Cellulose II. Although Direct Blue 1 contains two methoxy groups and Direct Blue 53 contains two methyl groups, different effects of these groups on the structure of nascent Microbial Cellulose were not identified.
Lee R Lynd - One of the best experts on this subject based on the ideXlab platform.
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Development of a Multipoint Quantitation Method to Simultaneously Measure Enzymatic and Structural Components of the Clostridium thermocellum Cellulosome Protein Complex
Journal of Proteome Research, 2013Co-Authors: Andrew B. Dykstra, Lee R Lynd, Lois A. St Brice, Miguel Á. Rodríguez, Babu Raman, Javier A. Izquierdo, Kelsey D. Cook, Robert L. HettichAbstract:Clostridium thermocellum has emerged as a leading bioenergy-relevant microbe due to its ability to solubilize Cellulose into carbohydrates, mediated by multicomponent membrane-attached complexes termed cellulosomes. To probe Microbial Cellulose utilization rates, it is desirable to be able to measure the concentrations of saccharolytic enzymes and estimate the total amount of cellulosome present on a mass basis. Current cellulase determination methodologies involve labor-intensive purification procedures and only allow for indirect determination of abundance. We have developed a method using multiple reaction monitoring (MRM-MS) to simultaneously quantitate both enzymatic and structural components of the cellulosome protein complex in samples ranging in complexity from purified cellulosomes to whole cell lysates, as an alternative to a previously developed enzyme-linked immunosorbent assay (ELISA) method of cellulosome quantitation. The precision of the cellulosome mass concentration in technical replicat...
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diversity of bacteria and glycosyl hydrolase family 48 genes in cellulolytic consortia enriched from thermophilic biocompost
Applied and Environmental Microbiology, 2010Co-Authors: Lee R Lynd, Javier A. Izquierdo, Maria SizovaAbstract:The enrichment from nature of novel Microbial communities with high cellulolytic activity is useful in the identification of novel organisms and novel functions that enhance the fundamental understanding of Microbial Cellulose degradation. In this work we identify predominant organisms in three cellulolytic enrichment cultures with thermophilic compost as an inoculum. Community structure based on 16S rRNA gene clone libraries featured extensive representation of clostridia from cluster III, with minor representation of clostridial clusters I and XIV and a novel Lutispora species cluster. Our studies reveal different levels of 16S rRNA gene diversity, ranging from 3 to 18 operational taxonomic units (OTUs), as well as variability in community membership across the three enrichment cultures. By comparison, glycosyl hydrolase family 48 (GHF48) diversity analyses revealed a narrower breadth of novel clostridial genes associated with cultured and uncultured Cellulose degraders. The novel GHF48 genes identified in this study were related to the novel clostridia Clostridium straminisolvens and Clostridium clariflavum, with one cluster sharing as little as 73% sequence similarity with the closest known relative. In all, 14 new GHF48 gene sequences were added to the known diversity of 35 genes from cultured species.
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Consolidated bioprocessing of cellulosic biomass: an update
Current Opinion in Biotechnology, 2005Co-Authors: Lee R Lynd, John Mcbride, Mark LaserAbstract:Biologically mediated processes seem promising for energy conversion, in particular for the conversion of lignocellulosic biomass into fuels. Although processes featuring a step dedicated to the production of cellulase enzymes have been the focus of most research efforts to date, consolidated bioprocessing (CBP) – featuring cellulase production, Cellulose hydrolysis and fermentation in one step – is an alternative approach with outstanding potential. Progress in developing CBP-enabling microorganisms is being made through two strategies: engineering naturally occurring cellulolytic microorganisms to improve product-related properties, such as yield and titer, and engineering non-cellulolytic organisms that exhibit high product yields and titers to express a heterologous cellulase system enabling Cellulose utilization. Recent studies of the fundamental principles of Microbial Cellulose utilization support the feasibility of CBP.
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Quantitative determination of cellulase concentration as distinct from cell concentration in studies of Microbial Cellulose utilization: Analytical framework and methodological approach
Biotechnology and Bioengineering, 2002Co-Authors: Lee R Lynd, Yiheng ZhangAbstract:In analyzing Microbial Cellulose utilization, it would be useful to independently measure the mass concentration of cells and cellulase enzymes. Such measurements would allow investigation of the allocation of cellular resources between synthesis of cells and cellulase, in vivo cell- and cellulase-specific Cellulose hydrolysis rates, and bioenergetics. Methodological protocols are not established for independent determination of cell and cellulase concentrations for the common case in which a substantial fraction of cellulase is attached to the cell surface. Alternative analytical approaches by which to develop such protocols are examined from the perspective of error minimization. For cell concentration measurement, acceptable accuracy is expected when the concentrations of a cell-specific component (e.g., DNA) is determined or when total protein is determined in conjunction with a measurement specific to cellulase. For cellulase concentration measurement, acceptable accuracy is expected when a measurement specific to cellulase such as ELISA is used. Several analytical approaches are rejected based on large expected errors.
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Microbial Cellulose Utilization: Fundamentals and Biotechnology
Microbiology and Molecular Biology Reviews, 2002Co-Authors: Lee R Lynd, Willem H. Van Zyl, Paul J Weimer, Isak S. PretoriusAbstract:Fundamental features of Microbial Cellulose utilization are examined at successively higher levels of aggregation encompassing the structure and composition of cellulosic biomass, taxonomic diversity, cellulase enzyme systems, molecular biology of cellulase enzymes, physiology of cellulolytic microorganisms, ecological aspects of cellulase-degrading communities, and rate-limiting factors in nature. The methodological basis for studying Microbial Cellulose utilization is considered relative to quantification of cells and enzymes in the presence of solid substrates as well as apparatus and analysis for Cellulose-grown continuous cultures. Quantitative description of Cellulose hydrolysis is addressed with respect to adsorption of cellulase enzymes, rates of enzymatic hydrolysis, bioenergetics of Microbial Cellulose utilization, kinetics of Microbial Cellulose utilization, and contrasting features compared to soluble substrate kinetics. A biological perspective on processing cellulosic biomass is presented, including features of pretreated substrates and alternative process configurations. Organism development is considered for "consolidated bioprocessing" (CBP), in which the production of cellulolytic enzymes, hydrolysis of biomass, and fermentation of resulting sugars to desired products occur in one step. Two organism development strategies for CBP are examined: (i) improve product yield and tolerance in microorganisms able to utilize Cellulose, or (ii) express a heterologous system for Cellulose hydrolysis and utilization in microorganisms that exhibit high product yield and tolerance. A concluding discussion identifies unresolved issues pertaining to Microbial Cellulose utilization, suggests approaches by which such issues might be resolved, and contrasts a Microbially oriented Cellulose hydrolysis paradigm to the more conventional enzymatically oriented paradigm in both fundamental and applied contexts.
Amir Hossein Mahvi - One of the best experts on this subject based on the ideXlab platform.
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Simultaneous nitrification and denitrification using a polypyrrole/Microbial Cellulose electrode in a membraneless bio-electrochemical system
RSC Advances, 2020Co-Authors: Hooshyar Hossini, Abbas Rezaee, Bita Ayati, Amir Hossein MahviAbstract:In this study, the feasibility of ammonium and total nitrogen (TN) removal from aqueous solution using a simultaneous nitrification and denitrification process was studied in a membraneless (single chamber) bio-electrochemical system with a novel electrode. The main objectives were to synthesize a polypyrrole/Microbial Cellulose (PPy/MC) composite and utilize it as a novel electrode material. To determine the mechanical properties of PPy/MC, the tensile strength and Young’s modulus were investigated. A biofilm was prepared using the fabricated electrode during the first few weeks. Effective parameters such as initial ammonium concentrations (NH4+ ∼ 15–150 mg N L−1), HRT (6–72 h), carbon/nitrogen ratio (C/N ratio ∼ 0–4), current intensity (2–10 mA), and pH (6.5–8.5) were evaluated. The following optimum values were obtained: HRT, 24 h; C/N ratio, 2; electric current, 6 mA; and pH, 7–7.5 at a constant ammonium concentration of 77.77 mg N L−1. It can be concluded from the experimental data that under optimal conditions about 97.42 and 62.47% of ammonium and TN were removed successfully, respectively.
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simultaneous nitrification and denitrification using a polypyrrole Microbial Cellulose electrode in a membraneless bio electrochemical system
RSC Advances, 2015Co-Authors: Hooshyar Hossini, Abbas Rezaee, Bita Ayati, Amir Hossein MahviAbstract:In this study, the feasibility of ammonium and total nitrogen (TN) removal from aqueous solution using a simultaneous nitrification and denitrification process was studied in a membraneless (single chamber) bio-electrochemical system with a novel electrode. The main objectives were to synthesize a polypyrrole/Microbial Cellulose (PPy/MC) composite and utilize it as a novel electrode material. To determine the mechanical properties of PPy/MC, the tensile strength and Young’s modulus were investigated. A biofilm was prepared using the fabricated electrode during the first few weeks. Effective parameters such as initial ammonium concentrations (NH4+ ∼ 15–150 mg N L−1), HRT (6–72 h), carbon/nitrogen ratio (C/N ratio ∼ 0–4), current intensity (2–10 mA), and pH (6.5–8.5) were evaluated. The following optimum values were obtained: HRT, 24 h; C/N ratio, 2; electric current, 6 mA; and pH, 7–7.5 at a constant ammonium concentration of 77.77 mg N L−1. It can be concluded from the experimental data that under optimal conditions about 97.42 and 62.47% of ammonium and TN were removed successfully, respectively.
Malcolm R Brown - One of the best experts on this subject based on the ideXlab platform.
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the future prospects of Microbial Cellulose in biomedical applications
Biomacromolecules, 2007Co-Authors: Wojciech Czaja, David J Young, Marek Kawecki, Malcolm R BrownAbstract:Microbial Cellulose has proven to be a remarkably versatile biomaterial and can be used in wide variety of applied scientific endeavors, such as paper products, electronics, acoustics, and biomedical devices. In fact, biomedical devices recently have gained a significant amount of attention because of an increased interest in tissue-engineered products for both wound care and the regeneration of damaged or diseased organs. Due to its unique nanostructure and properties, Microbial Cellulose is a natural candidate for numerous medical and tissue-engineered applications. For example, a Microbial Cellulose membrane has been successfully used as a wound-healing device for severely damaged skin and as a small-diameter blood vessel replacement. The nonwoven ribbons of Microbial Cellulose microfibrils closely resemble the structure of native extracellullar matrices, suggesting that it could function as a scaffold for the production of many tissue-engineered constructs. In addition, Microbial Cellulose membranes, ...
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Microbial Cellulose the natural power to heal wounds
Biomaterials, 2006Co-Authors: Wojciech Czaja, A Krystynowicz, Stanislaw Bielecki, Malcolm R BrownAbstract:Microbial Cellulose (MC) synthesized in abundance by Acetobacter xylinum shows vast potential as a novel wound healing system. The high mechanical strength and remarkable physical properties result from the unique nanostructure of the never-dried membrane. This article attempts to briefly summarize the recent developments and applications of MC in the emerging field of novel wound dressings and skin substitutes. It considers the properties of the synthesized material, its clinical performance, as well as progress in the commercialization of MC for wound care products. Efficient and inexpensive fermentation techniques, not presently available, will be necessary to produce large quantities of the polymer.
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structural investigations of Microbial Cellulose produced in stationary and agitated culture
Cellulose, 2004Co-Authors: Wojciech Czaja, Dwight K Romanovicz, Malcolm R BrownAbstract:Structural characteristics of Microbial Cellulose synthesized by two different methods have been compared using FT-IR and X-ray diffraction techniques. Cellulose synthesized by Acetobacter xylinum NQ-5 strain from agitated culture conditions is characterized by a lower Iϑ mass fraction than Cellulose that was produced statically. Such a decrease was in good correlation with smaller crystallite sizes of microfibrils produced in agitated culture. Formation of characteristic Cellulose spheres during agitation has been investigated by various electron and light microscopic methods. On this basis, a hypothetical mechanism of sphere formation and cell arrangement in the agitated culture has been proposed. During agitation, cells are stacked together in organized groups around the outer surface of the Cellulose sphere.
Hooshyar Hossini - One of the best experts on this subject based on the ideXlab platform.
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Simultaneous nitrification and denitrification using a polypyrrole/Microbial Cellulose electrode in a membraneless bio-electrochemical system
RSC Advances, 2020Co-Authors: Hooshyar Hossini, Abbas Rezaee, Bita Ayati, Amir Hossein MahviAbstract:In this study, the feasibility of ammonium and total nitrogen (TN) removal from aqueous solution using a simultaneous nitrification and denitrification process was studied in a membraneless (single chamber) bio-electrochemical system with a novel electrode. The main objectives were to synthesize a polypyrrole/Microbial Cellulose (PPy/MC) composite and utilize it as a novel electrode material. To determine the mechanical properties of PPy/MC, the tensile strength and Young’s modulus were investigated. A biofilm was prepared using the fabricated electrode during the first few weeks. Effective parameters such as initial ammonium concentrations (NH4+ ∼ 15–150 mg N L−1), HRT (6–72 h), carbon/nitrogen ratio (C/N ratio ∼ 0–4), current intensity (2–10 mA), and pH (6.5–8.5) were evaluated. The following optimum values were obtained: HRT, 24 h; C/N ratio, 2; electric current, 6 mA; and pH, 7–7.5 at a constant ammonium concentration of 77.77 mg N L−1. It can be concluded from the experimental data that under optimal conditions about 97.42 and 62.47% of ammonium and TN were removed successfully, respectively.
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Microbial Cellulose as a support for photocatalytic oxidation of toluene using TiO2nanoparticles
Journal of Applied Polymer Science, 2016Co-Authors: Abbas Rezaee, Golamhossin Pourtagi, Hooshyar Hossini, Mahshid LoloiAbstract:© 2015 Wiley Periodicals, Inc. The aim of this study was to investigate the feasibility of toluene degradation using impregnated Microbial Cellulose (MC) with titanium dioxide (TiO 2 ) nanoparticles (MC/TiO 2 ). The effects of the initial toluene concentration and ultraviolet (UV) source on the degradation efficiency of toluene have been evaluated. The experimental results showed that the rate of toluene degradation decreased with an increasing of the inlet toluene concentration. After 40 min reaction time, the decomposition rate (%) of toluene decreased from 72.3% to 36.02% for experiments conducted at 100 and 500 ppm, respectively. The degradation efficiency of toluene decreased with application of UVA source instead of UVC source. The toluene degradation efficiency (%) reached to 87.79% and 76.87% for UVC and UVA irradiation, respectively. At initial toluene concentration of 100 mg/L, toluene degradation efficiency for photocatalysis and photolysis processes were 70.2% and 10.65%, respectively; indicating that the photocatalytic degradation efficiency is significantly higher than that of photolytic degradation efficiency. Furthermore, photocatalytic degradation kinetics of toluene was studied and the rates of degradation were found to conform to pseudo-second-order kinetic. As shown in the present study, impregnation of TiO 2 nanoparticles on MC/TiO 2 significantly increases toluene removal for short exposure time. It can be concluded that the MC acted as a local toluene concentrator by adsorbing pollutants from the air stream, and thereby diffusing them to the TiO 2 nanoparticles for photodegradation.
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Microbial Cellulose as a support for photocatalytic oxidation of toluene using TiO2 nanoparticles
Journal of Applied Polymer Science, 2015Co-Authors: Abbas Rezaee, Golamhossin Pourtagi, Hooshyar Hossini, Mahshid LoloiAbstract:The aim of this study was to investigate the feasibility of toluene degradation using impregnated Microbial Cellulose (MC) with titanium dioxide (TiO2) nanoparticles (MC/TiO2). The effects of the initial toluene concentration and ultraviolet (UV) source on the degradation efficiency of toluene have been evaluated. The experimental results showed that the rate of toluene degradation decreased with an increasing of the inlet toluene concentration. After 40 min reaction time, the decomposition rate (%) of toluene decreased from 72.3% to 36.02% for experiments conducted at 100 and 500 ppm, respectively. The degradation efficiency of toluene decreased with application of UVA source instead of UVC source. The toluene degradation efficiency (%) reached to 87.79% and 76.87% for UVC and UVA irradiation, respectively. At initial toluene concentration of 100 mg/L, toluene degradation efficiency for photocatalysis and photolysis processes were 70.2% and 10.65%, respectively; indicating that the photocatalytic degradation efficiency is significantly higher than that of photolytic degradation efficiency. Furthermore, photocatalytic degradation kinetics of toluene was studied and the rates of degradation were found to conform to pseudo-second-order kinetic. As shown in the present study, impregnation of TiO2 nanoparticles on MC/TiO2 significantly increases toluene removal for short exposure time. It can be concluded that the MC acted as a local toluene concentrator by adsorbing pollutants from the air stream, and thereby diffusing them to the TiO2 nanoparticles for photodegradation. © 2015 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2016, 133, 43051.
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simultaneous nitrification and denitrification using a polypyrrole Microbial Cellulose electrode in a membraneless bio electrochemical system
RSC Advances, 2015Co-Authors: Hooshyar Hossini, Abbas Rezaee, Bita Ayati, Amir Hossein MahviAbstract:In this study, the feasibility of ammonium and total nitrogen (TN) removal from aqueous solution using a simultaneous nitrification and denitrification process was studied in a membraneless (single chamber) bio-electrochemical system with a novel electrode. The main objectives were to synthesize a polypyrrole/Microbial Cellulose (PPy/MC) composite and utilize it as a novel electrode material. To determine the mechanical properties of PPy/MC, the tensile strength and Young’s modulus were investigated. A biofilm was prepared using the fabricated electrode during the first few weeks. Effective parameters such as initial ammonium concentrations (NH4+ ∼ 15–150 mg N L−1), HRT (6–72 h), carbon/nitrogen ratio (C/N ratio ∼ 0–4), current intensity (2–10 mA), and pH (6.5–8.5) were evaluated. The following optimum values were obtained: HRT, 24 h; C/N ratio, 2; electric current, 6 mA; and pH, 7–7.5 at a constant ammonium concentration of 77.77 mg N L−1. It can be concluded from the experimental data that under optimal conditions about 97.42 and 62.47% of ammonium and TN were removed successfully, respectively.
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Heterotrophic Biological Denitrification Using Microbial Cellulose as Carbon Source
Journal of Polymers and The Environment, 2010Co-Authors: Hatam Godini, Abbas Rezaee, Ali Khavanin, Afshin Nili Ahmadabadi, Sayedomid Rastegar, Hooshyar HossiniAbstract:The objective of this study was to investigate the feasibility of using a Microbial biopolymer produced by Acetobacter xylinum as a carbon source for heterotrophic biological denitrification. The denitrification rate, COD availability and nitrite concentration were response param- eters. Under the experimental conditions, a denitrification rate of about 0.74 kg NO3 - N/m 3 d at 6 h retention time was achieved with Microbial Cellulose (MC). The reactor efflu- ent contained significantly COD concentrations (20-86 mg/ L) so it was not carbon limited, and was receiving enough carbon to facilitate the denitrification process. The maxi- mum nitrite concentration in the effluent was found to be 0.4 mg/L. However, decreasing the retention time to 3 h significantly reduced the efficiency. It can be concluded that the MC is a suitable carbon source for nitrate removal in a heterotrophic biological denitrification process.