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Anthony I. Okoh - One of the best experts on this subject based on the ideXlab platform.
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bioflocculation potentials of a uronic acid containing glycoprotein produced by bacillus sp aemreg4 isolated from tyhume river south africa
3 Biotech, 2017Co-Authors: Nozipho Ntsangani, Leonard V Mabinya, Abiodun Oladele Olaniran, Kunle Okaiyeto, Nwodo U Uchechukwu, Anthony I. OkohAbstract:Bioflocculants are secondary metabolites produced by microorganisms during their growth which have received attentions due to their biodegradability, innocuousness and lack of secondary pollution from degradation intermediates. This study reports on a bioflocculant produced by Bacillus specie isolated from Thyume River in South Africa. The bacterial isolate was identified through 16S rDNA sequencing and the BLAST analysis of the nucleotide sequences revealed 99% similarity to Bacillus sp. BCT-7112. The sequence was subsequently deposited in the GenBank as Bacillus sp. AEMREG4 with accession number KP406729. The optimum culture conditions for bioflocculant production were an inoculum size 4% (v/v) (80%) and starch (81%) as well as yeast extract (82%) as sole carbon and nitrogen sources, respectively. Addition of Ca2+ greatly enhanced the Flocculating activity (76%) of crude bioflocculant over a wide range of pH 4–10 and retained high Flocculating activity when heated at 100 °C for 1 h. Chemical analyses of the purified bioflocculant revealed carbohydrate (79% w/w) as a predominant component followed by uronic acid (15% w/w) and protein (5% w/w). Fourier transform infrared spectrum revealed the presence of carboxyl, hydroxyl and methoxyl groups as the functional groups responsible for flocculation and the high flocculation activity achieved portends its industrial applicability.
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implications for public health demands alternatives to inorganic and synthetic flocculants bioflocculants as important candidates
MicrobiologyOpen, 2016Co-Authors: Kunle Okaiyeto, Leonard V Mabinya, Uchechukwu U. Nwodo, Stanley A Okoli, Anthony I. OkohAbstract:Chemical flocculants are generally used in drinking water and wastewater treatment due to their efficacy and cost effectiveness. However, the question of their toxicity to human health and environmental pollution has been a major concern. In this article, we review the application of some chemical flocculants utilized in water treatment, and bioflocculants as a potential alternative to these chemical flocculants. To the best of our knowledge, there is no report in the literature that provides an up-to-date review of the relevant literature on both chemical flocculants and bioflocculants in one paper. As a result, this review paper comprehensively discussed the various chemical flocculants used in water treatment, including their advantages and disadvantages. It also gave insights into bioflocculants production, challenges, various factors influencing their Flocculating efficiency and their industrial applications, as well as future research directions including improvement of bioflocculants yields and Flocculating activity, and production of cation-independent bioflocculants. The molecular biology and synthesis of bioflocculants are also discussed.
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bacillus toyonensis strain aemreg6 a bacterium isolated from south african marine environment sediment samples produces a glycoprotein bioflocculant
Molecules, 2015Co-Authors: Kunle Okaiyeto, Leonard V Mabinya, Uchechukwu U. Nwodo, Anthony I. OkohAbstract:A bioflocculant-producing bacteria, isolated from sediment samples of a marine environment in the Eastern Cape Province of South Africa demonstrated a Flocculating activity above 60% for kaolin clay suspension. Analysis of the 16S ribosomal deoxyribonucleic acid (rDNA) nucleotide sequence of the isolate in the GenBank database showed 99% similarity to Bacillus toyonensis strain BCT-7112 and it was deposited in the GenBank as Bacillus toyonensis strain AEMREG6 with accession number KP406731. The bacteria produced a bioflocculant (REG-6) optimally in the presence of glucose and NH4NO3 as the sole carbon and nitrogen source, respectively, initial medium pH of 5 and Ca2+ as the cation of choice. Chemical analysis showed that purified REG-6 was a glycoprotein mainly composed of polysaccharide (77.8%) and protein (11.5%). It was thermally stable and had strong Flocculating activity against kaolin suspension over a wide range of pH values (3–11) with a relatively low dosage requirement of 0.1 mg/mL in the presence of Mn2+. Fourier transform infrared spectroscopy (FTIR) revealed the presence of hydroxyl, carboxyl and amide groups preferred for flocculation. Scanning electron microscopy (SEM) revealed that bridging was the main flocculation mechanism of REG-6. The outstanding Flocculating performance of REG-6 holds great potential to replace the hazardous chemical flocculants currently used in water treatment.
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characterization of a bioflocculant produced by a consortium of halomonas sp okoh and micrococcus sp leo
International Journal of Environmental Research and Public Health, 2013Co-Authors: Kunle Okaiyeto, Leonard V Mabinya, Uchechukwu U. Nwodo, Anthony I. OkohAbstract:The physicochemical and Flocculating properties of a bioflocculant produced by a bacterial consortium composed of Halomonas sp. Okoh and Micrococcus sp. Leo were investigated. The purified bioflocculant was cation and pH dependent, and optimally flocculated kaolin clay suspension at a dosage of 0.1 mg/mL. The Flocculating activity of the bioflocculant was stimulated in the presence of Ca2+, Mn2+, Al3+ and had a wide pH range of 2–10, with the highest Flocculating activity of 86% at pH 8. The bioflocculant was thermostable and retained more than 70% of its Flocculating activity after being heated at 80 °C for 30 min. Thermogravimetric analyses revealed a partial thermal decomposition of the biofloculant at 400 °C. The infrared spectrum showed the presence of hydroxyl, carboxyl and amino moieties as functional groups. The bioflocculant produced by the bacterial consortium appears to hold promising alternative to inorganic and synthetic organic flocculants that are widely used in wastewater treatment.
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Characterization of an Exopolymeric Flocculant Produced by a Brachybacterium sp.
Materials (Basel Switzerland), 2013Co-Authors: Uchechukwu U. Nwodo, Mayowa Oladele Agunbiade, Ezekiel Green, M Nwamadi, Karl Rumbold, Anthony I. OkohAbstract:We evaluated the bioflocculant production potential of an Actinobacteria, which was isolated from a freshwater environment in the Eastern Cape province of South Africa. 16S rDNA nucleotide sequencing analyses revealed that the actinobacteria belongs to the Brachybacterium genus, and the sequences were deposited in the GenBank as Brachybacterium sp. UFH, with accession number HQ537131. Optimum fermentation conditions for bioflocculant production by the bacteria include an initial medium pH of 7.2, incubation temperature of 30 °C, agitation speed of 160 rpm and an inoculum size of 2% (vol/vol) of cell density 3.0 × 108 CFU/mL. The carbon, nitrogen and cation sources for optimum bioflocculant production were maltose (83% Flocculating activity), urea (91.17% Flocculating activity) and MgCl2 (91.16% Flocculating activity). Optimum bioflocculant production coincided with the logarithmic growth phase of the bacteria, and chemical analyses of the bioflocculant showed 39.4% carbohydrate and 43.7% protein (wt/wt). The mass ratio of neutral sugar, amino sugar and uronic acids was 1.3:0.7:2.2. Fourier transform infrared spectroscopy (FTIR) indicated the presence of carboxyl, hydroxyl and amino groups, amongst others, typical for heteropolysaccharide and glycosaminoglycan polysaccharides. Bioflocculant pyrolysis showed thermal stability at over 600 °C, while scanning electron microscope (SEM) imaging revealed a maze-like structure of interlaced flakes. Its high flocculation activity suggests its suitability for industrial applicability.
J Wang - One of the best experts on this subject based on the ideXlab platform.
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flocculation behavior and mechanism of an exopolysaccharide from the deep sea psychrophilic bacterium pseudoalteromonas sp sm9913
Bioresource Technology, 2008Co-Authors: Wei Li, Weizhi Zhou, Yunchu Zhang, J WangAbstract:Abstract Flocculation behavior and mechanism of the exopolysaccharide secreted by Pseudoalteromonas sp. SM9913 (EPS SM9913), a psychrophilic bacterium isolated from 1855 m deep-sea sediment, has been studied in this paper. EPS SM9913 showed a peak Flocculating activity of 49.3 in 1 g/L kaolin suspension with 4.55 mmol/L CaCl 2 and the optimum pH range of 5–8. It appears that the Flocculating activity of EPS SM9913 was stimulated by Ca 2+ and Fe 2+ . This study found that EPS SM9913 showed a better flocculation performance than Al 2 (SO 4 ) 3 at salinity of 5–100‰ or temperatures of 5–15 °C. In addition, this EPS was effective to flocculate several other suspended solids. The measured zeta-potentials, the size of flocs formed during the flocculation process and the surface profile of flocs revealed by scan electron micrograph suggest that bridging is the main flocculation mechanism of the studied EPS. Deacetylation of EPS SM9913 resulted in a significant decrease in its Flocculating activity indicating that the large number of acetyl groups in EPS SM9913 played an important role in its flocculation performance.
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flocculation behavior and mechanism of an exopolysaccharide from the deep sea psychrophilic bacterium pseudoalteromonas sp sm9913
Bioresource Technology, 2008Co-Authors: Weizhi Zhou, Yunchu Zhang, J Wang, Xiwang ZhuAbstract:Flocculation behavior and mechanism of the exopolysaccharide secreted by Pseudoalteromonas sp. SM9913 (EPS SM9913), a psychrophilic bacterium isolated from 1855m deep-sea sediment, has been studied in this paper. EPS SM9913 showed a peak Flocculating activity of 49.3 in 1g/L kaolin suspension with 4.55mmol/L CaCl2 and the optimum pH range of 5-8. It appears that the Flocculating activity of EPS SM9913 was stimulated by Ca2+ and Fe2+. This study found that EPS SM9913 showed a better flocculation performance than Al2(SO4)3 at salinity of 5-100 per thousand or temperatures of 5-15 degrees C. In addition, this EPS was effective to flocculate several other suspended solids. The measured zeta-potentials, the size of flocs formed during the flocculation process and the surface profile of flocs revealed by scan electron micrograph suggest that bridging is the main flocculation mechanism of the studied EPS. Deacetylation of EPS SM9913 resulted in a significant decrease in its Flocculating activity indicating that the large number of acetyl groups in EPS SM9913 played an important role in its flocculation performance.
Rongshi Cheng - One of the best experts on this subject based on the ideXlab platform.
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flocculation of escherichia coli using a quaternary ammonium salt grafted carboxymethyl chitosan flocculant
Environmental Science & Technology, 2014Co-Authors: Zhen Yang, Hu Yang, Jeanregis Degorcedumas, Eric Guibal, Rongshi ChengAbstract:Only few studies are available on bacteria removal efficiencies and antibacterial properties of flocculants, which is one of the important requirements in water treatment work. Escherichia coli (E. coli) was selected as an example of a Gram-negative bacteria for testing the Flocculating properties of a quaternary ammonium salt grafted chitosan (carboxymethyl chitosan-graft-poly[(2-methacryloyloxyethyl) trimethylammonium chloride] copolymer; i.e., CMC-g-PDMC). The effect of various flocculation parameters, including flocculant dosage, initial bacterial density, nutrient medium content, and pH were successively investigated. The experimental results indicated that, besides flocculation effects, CMC-g-PDMC also exhibited a bactericidal effect (not requiring additional treatment facilities). Moreover, the flocculation mechanisms were investigated via zeta potential measurements, floc observation, and three-dimensional excitation–emission matrix spectra analysis. Apart from its Flocculating and settling effect...
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Flocculation of Escherichia coli Using a Quaternary Ammonium Salt Grafted Carboxymethyl Chitosan Flocculant
ENVIRONMENTAL SCIENCE & TECHNOLOGY, 2014Co-Authors: Zhen Yang, Hu Yang, Eric Guibal, Jean-regis Degorce-dumas, Rongshi ChengAbstract:Only few studies are available on bacteria removal efficiencies and antibacterial properties of flocculants, which is one of the important requirements in water treatment work. Escherichia coli (E. coli) was selected as an example of a Gram-negative bacteria for testing the Flocculating properties of a quaternary ammonium salt grafted chitosan (carboxymethyl chitosangraft-poly[(2-methacryloyloxyethyl) trimethylammonium chloride] copolymer; i.e., CMC-g-PDMC). The effect of various flocculation parameters, including flocculant dosage, initial bacterial density, nutrient medium content, and pH were successively investigated. The experimental results indicated that, besides flocculation effects, CMC-g-PDMC also exhibited a bactericidal effect (not requiring additional treatment facilities). Moreover, the flocculation mechanisms were investigated via zeta potential measurements, floc observation, and three-dimensional excitation-emission matrix spectra analysis. Apart from its Flocculating and settling effect, this chitosan-based material has bactericidal action through the breaking of bacterial cell walls by grafted quaternary ammonium salt.
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preparation of strong cationic chitosan graft polyacrylamide flocculants and their Flocculating properties
Industrial & Engineering Chemistry Research, 2011Co-Authors: Yaobo Lu, Zhen Yang, Yabo Shang, Xin Huang, Aimin Chen, Yuxiang Jiang, Wei Gu, Xiaozhi Qian, Hu Yang, Rongshi ChengAbstract:Recently, more attentions have been paid to natural polymer-based flocculants in water treatment, since they are believed to be low-cost, nontoxic, and environmentally friendly materials. In this work, strong cationic chitosan-based graft copolymer flocculants (3-chloro-2-hydroxypropyl trimethyl ammonium chloride (CTA) modified chitosan-graft-polyacrylamide, denoted as chitosan-CTA-g-PAM) have been prepared, and their Flocculating properties were studied systematically, both at the laboratory scale and at the pilot scale. In laboratory scale, a kaolin suspension was employed as synthetic wastewater. The effects of dosage, temperature, and original turbidity of untreated wastewater were investigated, respectively. Moreover, in pilot scale, the raw water from the Zhenjiang part of the Yangtse River in China was used as wastewater. The influences of three external factors—dosage, sedimentation time, and mechanical mixing rate—on the Flocculating performances have been studied by orthogonal testing, respectiv...
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the Flocculating properties of chitosan graft polyacrylamide flocculants i effect of the grafting ratio
Journal of Applied Polymer Science, 2010Co-Authors: Bo Yuan, Yabo Shang, Yaobo Lu, Aimin Chen, Yuxiang Jiang, Xiaozhi Qian, Hu Yang, Guangzhi Wang, Rongshi ChengAbstract:A series of chitosan-graft-polyacrylamide copolymers have been prepared as flocculants for waste water treatment. The results indicated that the grafting ratio was one of the key factors for the Flocculating effects. The copolymers with various grafting ratios showed different Flocculating properties. To observe every detail of this effect, the specific refractive index increment measurement (SRIIM) method was used to determine the grafting ratio at the beginning of this study. Interestingly, it was found that as the grafting ratio increased, the Flocculating effect increased until it reached its maximum point. At that point, it decreased. This result was discussed in terms of the cooperative effects of the charge neutralization and bridging Flocculating mechanisms. A structure model of chitosan-g-polyacrylamide copolymer flocculants has been proposed. © 2010 Wiley Periodicals, Inc. J Appl Polym Sci, 2010
Weizhi Zhou - One of the best experts on this subject based on the ideXlab platform.
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flocculation behavior and mechanism of an exopolysaccharide from the deep sea psychrophilic bacterium pseudoalteromonas sp sm9913
Bioresource Technology, 2008Co-Authors: Wei Li, Weizhi Zhou, Yunchu Zhang, J WangAbstract:Abstract Flocculation behavior and mechanism of the exopolysaccharide secreted by Pseudoalteromonas sp. SM9913 (EPS SM9913), a psychrophilic bacterium isolated from 1855 m deep-sea sediment, has been studied in this paper. EPS SM9913 showed a peak Flocculating activity of 49.3 in 1 g/L kaolin suspension with 4.55 mmol/L CaCl 2 and the optimum pH range of 5–8. It appears that the Flocculating activity of EPS SM9913 was stimulated by Ca 2+ and Fe 2+ . This study found that EPS SM9913 showed a better flocculation performance than Al 2 (SO 4 ) 3 at salinity of 5–100‰ or temperatures of 5–15 °C. In addition, this EPS was effective to flocculate several other suspended solids. The measured zeta-potentials, the size of flocs formed during the flocculation process and the surface profile of flocs revealed by scan electron micrograph suggest that bridging is the main flocculation mechanism of the studied EPS. Deacetylation of EPS SM9913 resulted in a significant decrease in its Flocculating activity indicating that the large number of acetyl groups in EPS SM9913 played an important role in its flocculation performance.
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flocculation behavior and mechanism of an exopolysaccharide from the deep sea psychrophilic bacterium pseudoalteromonas sp sm9913
Bioresource Technology, 2008Co-Authors: Weizhi Zhou, Yunchu Zhang, J Wang, Xiwang ZhuAbstract:Flocculation behavior and mechanism of the exopolysaccharide secreted by Pseudoalteromonas sp. SM9913 (EPS SM9913), a psychrophilic bacterium isolated from 1855m deep-sea sediment, has been studied in this paper. EPS SM9913 showed a peak Flocculating activity of 49.3 in 1g/L kaolin suspension with 4.55mmol/L CaCl2 and the optimum pH range of 5-8. It appears that the Flocculating activity of EPS SM9913 was stimulated by Ca2+ and Fe2+. This study found that EPS SM9913 showed a better flocculation performance than Al2(SO4)3 at salinity of 5-100 per thousand or temperatures of 5-15 degrees C. In addition, this EPS was effective to flocculate several other suspended solids. The measured zeta-potentials, the size of flocs formed during the flocculation process and the surface profile of flocs revealed by scan electron micrograph suggest that bridging is the main flocculation mechanism of the studied EPS. Deacetylation of EPS SM9913 resulted in a significant decrease in its Flocculating activity indicating that the large number of acetyl groups in EPS SM9913 played an important role in its flocculation performance.
Leonard V Mabinya - One of the best experts on this subject based on the ideXlab platform.
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bioflocculation potentials of a uronic acid containing glycoprotein produced by bacillus sp aemreg4 isolated from tyhume river south africa
3 Biotech, 2017Co-Authors: Nozipho Ntsangani, Leonard V Mabinya, Abiodun Oladele Olaniran, Kunle Okaiyeto, Nwodo U Uchechukwu, Anthony I. OkohAbstract:Bioflocculants are secondary metabolites produced by microorganisms during their growth which have received attentions due to their biodegradability, innocuousness and lack of secondary pollution from degradation intermediates. This study reports on a bioflocculant produced by Bacillus specie isolated from Thyume River in South Africa. The bacterial isolate was identified through 16S rDNA sequencing and the BLAST analysis of the nucleotide sequences revealed 99% similarity to Bacillus sp. BCT-7112. The sequence was subsequently deposited in the GenBank as Bacillus sp. AEMREG4 with accession number KP406729. The optimum culture conditions for bioflocculant production were an inoculum size 4% (v/v) (80%) and starch (81%) as well as yeast extract (82%) as sole carbon and nitrogen sources, respectively. Addition of Ca2+ greatly enhanced the Flocculating activity (76%) of crude bioflocculant over a wide range of pH 4–10 and retained high Flocculating activity when heated at 100 °C for 1 h. Chemical analyses of the purified bioflocculant revealed carbohydrate (79% w/w) as a predominant component followed by uronic acid (15% w/w) and protein (5% w/w). Fourier transform infrared spectrum revealed the presence of carboxyl, hydroxyl and methoxyl groups as the functional groups responsible for flocculation and the high flocculation activity achieved portends its industrial applicability.
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implications for public health demands alternatives to inorganic and synthetic flocculants bioflocculants as important candidates
MicrobiologyOpen, 2016Co-Authors: Kunle Okaiyeto, Leonard V Mabinya, Uchechukwu U. Nwodo, Stanley A Okoli, Anthony I. OkohAbstract:Chemical flocculants are generally used in drinking water and wastewater treatment due to their efficacy and cost effectiveness. However, the question of their toxicity to human health and environmental pollution has been a major concern. In this article, we review the application of some chemical flocculants utilized in water treatment, and bioflocculants as a potential alternative to these chemical flocculants. To the best of our knowledge, there is no report in the literature that provides an up-to-date review of the relevant literature on both chemical flocculants and bioflocculants in one paper. As a result, this review paper comprehensively discussed the various chemical flocculants used in water treatment, including their advantages and disadvantages. It also gave insights into bioflocculants production, challenges, various factors influencing their Flocculating efficiency and their industrial applications, as well as future research directions including improvement of bioflocculants yields and Flocculating activity, and production of cation-independent bioflocculants. The molecular biology and synthesis of bioflocculants are also discussed.
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bacillus toyonensis strain aemreg6 a bacterium isolated from south african marine environment sediment samples produces a glycoprotein bioflocculant
Molecules, 2015Co-Authors: Kunle Okaiyeto, Leonard V Mabinya, Uchechukwu U. Nwodo, Anthony I. OkohAbstract:A bioflocculant-producing bacteria, isolated from sediment samples of a marine environment in the Eastern Cape Province of South Africa demonstrated a Flocculating activity above 60% for kaolin clay suspension. Analysis of the 16S ribosomal deoxyribonucleic acid (rDNA) nucleotide sequence of the isolate in the GenBank database showed 99% similarity to Bacillus toyonensis strain BCT-7112 and it was deposited in the GenBank as Bacillus toyonensis strain AEMREG6 with accession number KP406731. The bacteria produced a bioflocculant (REG-6) optimally in the presence of glucose and NH4NO3 as the sole carbon and nitrogen source, respectively, initial medium pH of 5 and Ca2+ as the cation of choice. Chemical analysis showed that purified REG-6 was a glycoprotein mainly composed of polysaccharide (77.8%) and protein (11.5%). It was thermally stable and had strong Flocculating activity against kaolin suspension over a wide range of pH values (3–11) with a relatively low dosage requirement of 0.1 mg/mL in the presence of Mn2+. Fourier transform infrared spectroscopy (FTIR) revealed the presence of hydroxyl, carboxyl and amide groups preferred for flocculation. Scanning electron microscopy (SEM) revealed that bridging was the main flocculation mechanism of REG-6. The outstanding Flocculating performance of REG-6 holds great potential to replace the hazardous chemical flocculants currently used in water treatment.
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characterization of a bioflocculant produced by a consortium of halomonas sp okoh and micrococcus sp leo
International Journal of Environmental Research and Public Health, 2013Co-Authors: Kunle Okaiyeto, Leonard V Mabinya, Uchechukwu U. Nwodo, Anthony I. OkohAbstract:The physicochemical and Flocculating properties of a bioflocculant produced by a bacterial consortium composed of Halomonas sp. Okoh and Micrococcus sp. Leo were investigated. The purified bioflocculant was cation and pH dependent, and optimally flocculated kaolin clay suspension at a dosage of 0.1 mg/mL. The Flocculating activity of the bioflocculant was stimulated in the presence of Ca2+, Mn2+, Al3+ and had a wide pH range of 2–10, with the highest Flocculating activity of 86% at pH 8. The bioflocculant was thermostable and retained more than 70% of its Flocculating activity after being heated at 80 °C for 30 min. Thermogravimetric analyses revealed a partial thermal decomposition of the biofloculant at 400 °C. The infrared spectrum showed the presence of hydroxyl, carboxyl and amino moieties as functional groups. The bioflocculant produced by the bacterial consortium appears to hold promising alternative to inorganic and synthetic organic flocculants that are widely used in wastewater treatment.
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production and characterization of bioflocculant produced by halobacillus sp mvuyo isolated from bottom sediment of algoa bay
Environmental Technology, 2012Co-Authors: Sekelwa Cosa, Leonard V Mabinya, Abiodun Oladele Olaniran, Anthony Ifeanyi OkohAbstract:A bioflocculant-producing bacteria isolated from marine sediment of Algoa Bay was assessed for its bioflocculant-producing potentials. Based on 16S recombinant deoxyribonucleic acid (rDNA) sequence analysis, the isolate was identified as Halobacillus sp. and deposited in the Genbank as Halobacillus sp. Mvuyo with accession number HQ537125. The bacteria produced bioflocculant optimally in the presence of glucose (76% Flocculating activity) and ammonium chloride (93% Flocculating activity) as sole sources of carbon and nitrogen, respectively. The Flocculating capabilities of the flocculant were increased by the addition of Ca2+ (76% Flocculating activity) and the highest Flocculating activity was observed at neutral pH (7.0). The chemical analysis of the bioflocculant revealed that it contained mainly polysaccharide and protein.