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Show S, Akhter R, Paul I, Das P, Bal M, Bhattacharya R, Bose D, Mondal A, Saha S, Halder G. Efficacy of exopolysaccharide in dye-laden wastewater treatment: A comprehensive review. CHEMOSPHERE 2024; 355:141753. [PMID: 38531498 DOI: 10.1016/j.chemosphere.2024.141753] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/06/2023] [Revised: 03/12/2024] [Accepted: 03/16/2024] [Indexed: 03/28/2024]
Abstract
The discharge of dye-laden wastewater into the water streams causes severe water and soil pollution, which poses a global threat to aquatic ecosystems and humans. A diverse array of microorganisms such as bacteria, fungi, and algae produce exopolysaccharides (EPS) of different compositions and exhibit great bioflocculation potency to sustainably eradicate dyes from water bodies. Nanomodified chemical composites of EPS enable their recyclability during dye-laden wastewater treatment. Nevertheless, the selection of potent EPS-producing strains and physiological parameters of microbial growth and the remediation process could influence the removal efficiency of EPS. This review will intrinsically discuss the fundamental importance of EPS from diverse microbial origins and their nanomodified chemical composites, the mechanisms in EPS-mediated bioremediation of dyes, and the parametric influences on EPS-mediated dye removal through sorption/bioflocculation. This review will pave the way for designing and adopting futuristic green and sustainable EPS-based bioremediation strategies for dye-laden wastewater in situ and ex situ.
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Affiliation(s)
- Sumona Show
- Department of Chemical Engineering, National Institute of Technology Durgapur, Durgapur, 713209, West Bengal, India
| | - Ramisa Akhter
- Department of Biotechnology, National Institute of Technology Durgapur, Durgapur, 713209, West Bengal, India
| | - Indrani Paul
- Department of Biotechnology, Brainware University, Barasat, Kolkata, 700125, West Bengal, India
| | - Payal Das
- Department of Chemical Engineering, National Institute of Technology Durgapur, Durgapur, 713209, West Bengal, India
| | - Manisha Bal
- Department of Chemical Engineering, National Institute of Technology Durgapur, Durgapur, 713209, West Bengal, India
| | - Riya Bhattacharya
- School of Biotechnology, Shoolini University of Biotechnology and Management Sciences, Solan, 173229, Himachal Pradesh, India
| | - Debajyoti Bose
- School of Biotechnology, Shoolini University of Biotechnology and Management Sciences, Solan, 173229, Himachal Pradesh, India
| | - Amita Mondal
- Department of Chemistry, Vedanta College, Kolkata, 700054, West Bengal, India
| | - Shouvik Saha
- Department of Biotechnology, Brainware University, Barasat, Kolkata, 700125, West Bengal, India.
| | - Gopinath Halder
- Department of Chemical Engineering, National Institute of Technology Durgapur, Durgapur, 713209, West Bengal, India.
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Segura A, Molina L. LuxR402 of Novosphingobium sp. HR1a regulates the correct configuration of cell envelopes. Front Microbiol 2023; 14:1205860. [PMID: 37577419 PMCID: PMC10413115 DOI: 10.3389/fmicb.2023.1205860] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/14/2023] [Accepted: 07/10/2023] [Indexed: 08/15/2023] Open
Abstract
Although there is some evidence to suggest that LuxR-solo proteins participate in inter-species or even inter-kingdom communication, most of the LuxR-solo protein functions are unknown. We have characterized the LuxR402 regulator of Novosphingobium sp. HR1a, a bacterial strain with the ability to establish high numbers in the plant rhizosphere and able to degrade a wide range of polycyclic aromatic hydrocarbons. LuxR402 controls the aggregation state of the bacterial culture; cultures of a mutant strain lacking this regulator flocculate in less than 3 h without agitation. We have demonstrated that the bacterial surface of the mutant is highly hydrophobic and that the mutant cells assimilate sugars slower than the wild-type. The flocculation mechanism has been demonstrated to be involved in the survival of the strain under unfavorable conditions; the luxR402 gene is repressed and produces flocculation in the presence of salicylate, a substrate that, although being assimilated by Novosphingobium, is toxic to cells at high concentrations. The flocculation of cultures in industrial setups has mainly been achieved through the addition of chemicals; these studies open up the possibility of controlling the flocculation by regulating the level of expression of the luxR402 gene.
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Affiliation(s)
| | - Lázaro Molina
- Environmental Protection Department, Estación Experimental del Zaidín, Consejo Superior de Investigaciones Científicas, Madrid, Spain
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Bahniuk MS, Alidina F, Tan X, Unsworth LD. The last 25 years of research on bioflocculants for kaolin flocculation with recent trends and technical challenges for the future. Front Bioeng Biotechnol 2022; 10:1048755. [PMID: 36507274 PMCID: PMC9731118 DOI: 10.3389/fbioe.2022.1048755] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/19/2022] [Accepted: 11/09/2022] [Indexed: 11/27/2022] Open
Abstract
The generation of kaolin-containing wastewater is an inevitable consequence in a number of industries including mining, wastewater treatment, and bitumen processing. In some cases, the production of kaolin tailings waste during the production of bitumen or phosphate is as high as 3 times greater than the actual produced product. The existing inventory of nearly five billion barrels of oil sands tailings alone represents a massive storage and reclamation challenge, as well as a significant economic and environmental liability. Current reclamation options like inorganic coagulants and organic synthetic polymers may settle kaolin effectively, but may themselves pose an additional environmental hazard. Bioflocculants are an emerging alternative, given the inherent safety and biodegradability of their bio-based compositions. This review summarizes the different research attempts towards a better bioflocculant of kaolin, with a focus on the bioflocculant source, composition, and effective flocculating conditions. Bacillus bacteria were the most prevalent single species for bioflocculant production, with wastewater also hosting a large number of bioflocculant-producing microorganisms while serving as an inexpensive nutrient. Effective kaolin flocculation could be obtained over a broad range of pH values (1-12) and temperatures (5-95°C). Uronic acid and glutamic acid were predominant sugars and amino acids, respectively, in a number of effective bioflocculants, potentially due to their structural and charge similarities to effective synthetic polymers like polyacrylamide. Overall, these results demonstrate that bioflocculants can be produced from a wide range of microorganisms, can be composed of polysaccharides, protein or glycoproteins and can serve as effective treatment options for kaolin. In some cases, the next obstacle to their wide-spread application is scaling to industrially relevant volumes and their deployment strategies.
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Ibrahim HAH, Abou Elhassayeb HE, El-Sayed WMM. Potential functions and applications of diverse microbial exopolysaccharides in marine environments. J Genet Eng Biotechnol 2022; 20:151. [PMID: 36318392 PMCID: PMC9626724 DOI: 10.1186/s43141-022-00432-2] [Citation(s) in RCA: 15] [Impact Index Per Article: 7.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/30/2022] [Accepted: 10/08/2022] [Indexed: 01/25/2023]
Abstract
Exopolysaccharides (EPSs) from microorganisms are essential harmless natural biopolymers used in applications including medications, nutraceuticals and functional foods, cosmetics, and insecticides. Several microbes can synthesize and excrete EPSs with chemical properties and structures that make them suitable for several important applications. Microbes secrete EPSs outside their cell walls, as slime or as a "jelly" into the extracellular medium. These EPS-producing microbes are ubiquitous and can be isolated from aquatic and terrestrial environments, such as freshwater, marine water, wastewater, and soils. They have also been isolated from extreme niches like hot springs, cold waters, halophilic environments, and salt marshes. Recently, microbial EPSs have attracted interest for their applications such as environmental bio-flocculants because they are degradable and nontoxic. However, further efforts are required for the cost-effective and industrial-scale commercial production of microbial EPSs. This review focuses on the exopolysaccharides obtained from several extremophilic microorganisms, their synthesis, and manufacturing optimization for better cost and productivity. We also explored their role and applications in interactions between several organisms.
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Affiliation(s)
- Hassan A. H. Ibrahim
- grid.419615.e0000 0004 0404 7762Marine Microbiology Department, National Institute of Oceanography and Fisheries (NIOF), Cairo, 11516 Egypt
| | - Hala E. Abou Elhassayeb
- grid.419615.e0000 0004 0404 7762Marine Microbiology Department, National Institute of Oceanography and Fisheries (NIOF), Cairo, 11516 Egypt
| | - Waleed M. M. El-Sayed
- grid.419615.e0000 0004 0404 7762Marine Microbiology Department, National Institute of Oceanography and Fisheries (NIOF), Cairo, 11516 Egypt
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Selepe TN, Maliehe TS, Moganedi K, Masoko P, Mulaudzi V. Isolation and Optimisation of Culture Conditions for a Marine Bioflocculant-Producing Bacterium and Application of Its Bioflocculant in Wastewater Treatment. INTERNATIONAL JOURNAL OF ENVIRONMENTAL RESEARCH AND PUBLIC HEALTH 2022; 19:10237. [PMID: 36011872 PMCID: PMC9408499 DOI: 10.3390/ijerph191610237] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 06/29/2022] [Revised: 08/03/2022] [Accepted: 08/05/2022] [Indexed: 06/15/2023]
Abstract
The application of bioflocculants has become an alternative to that of chemical flocculants in wastewater treatment due to their environmental friendliness and non-toxic effects. This study aimed at isolating a bioflocculant-producing bacterium from marine water, optimisation of its culture conditions, and investigation of the removal efficiency of its bioflocculant on pollutants in wastewater. The bacterium was identified by 16S rRNA gene analysis. Optimal carbon and nitrogen sources, inoculum size, temperature, pH, and time were determined by the one-factor-at-a-time assay. The cytotoxicity of the bioflocculant was assessed on African green monkey kidney and bovine dermis cells using a tetrazolium-based columetric (MTT) method. Its removal efficiencies on chemical oxygen demand (COD), biological oxygen demand (BOD) and sulphur were determined using the Jar test method. The bacterial isolate was identified as Ochrobactrum oryzae AB84113. A maximum flocculating activity of 92% and a yield of 3.768 g/L were obtained when a 1% (v/v) inoculum size was used in the presence of starch and yeast extract at pH 7, 30 °C, and after 72 h of cultivation. The bioflocculant demonstrated non-cytotoxic effects on bovine dermis and African green monkey kidney cells. The bioflocculant removed 98% COD, 91% BOD and 86% of Sulphur. The bioflocculant has potential for pollutant removal from industrial wastewater.
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Affiliation(s)
- Tlou Nelson Selepe
- Department of Water and Sanitation, University of Limpopo, Private Bag X1106, Polokwane 0727, South Africa
| | - Tsolanku Sidney Maliehe
- Department of Biochemistry, Microbiology and Biotechnology, University of Limpopo, Private Bag X1106, Polokwane 0727, South Africa
| | - Kgabo Moganedi
- Department of Biochemistry, Microbiology and Biotechnology, University of Limpopo, Private Bag X1106, Polokwane 0727, South Africa
| | - Peter Masoko
- Department of Biochemistry, Microbiology and Biotechnology, University of Limpopo, Private Bag X1106, Polokwane 0727, South Africa
| | - Vusimuzi Mulaudzi
- Department of Chemistry, University of Limpopo, Private Bag X1106, Polokwane 0727, South Africa
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Isolation, Identification and Characterization of Bioflocculant-Producing Bacteria from Activated Sludge of Vulindlela Wastewater Treatment Plant. Appl Microbiol 2021. [DOI: 10.3390/applmicrobiol1030038] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
Abstract
The low microbial flocculant yields and efficiencies limit their industrial applications. There is a need to identify bacteria with high bioflocculant production. The aim of this study was to isolate and identify a bioflocculant-producing bacterium from activated sludge wastewater and characterise its bioflocculant activity. The identification of the isolated bacterium was performed by 16S rRNA gene sequencing analysis. The optimal medium composition (carbon and nitrogen sources, cations and inoculum size) and culture conditions (temperature, pH, shaking speed and time) were evaluated by the one-factor-at-a-time method. The morphology, functional groups, crystallinity and pyrolysis profile of the bioflocculant were analysed using scanning electron microscope (SEM), Fourier transform infrared (FTIR) and thermogravimetric (TGA) analysis. The bacterium was identified as Proteus mirabilis AB 932526.1. Its optimal medium and culture conditions were: sucrose (20 g/L), yeast extract (1.2 g/L), MnCl2 (1 g/L), pH 6, 30 °C, inoculation volume (3%), shaking speed (120 rpm) for 72 h of cultivation. SEM micrograph revealed the bioflocculant to be amorphous. FTIR analysis indicated the presence of hydroxyl, carboxyl and amino groups. The bioflocculant was completely pyrolyzed at temperatures above 800 °C. The bacterium has potential to produce bioflocculant of industrial importance.
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Du M, Wang L, Ebrahimi A, Chen G, Shu S, Zhu K, Shen C, Li B, Wang G. Extracellular polymeric substances induced cell-surface interactions facilitate bacteria transport in saturated porous media. ECOTOXICOLOGY AND ENVIRONMENTAL SAFETY 2021; 218:112291. [PMID: 33957420 DOI: 10.1016/j.ecoenv.2021.112291] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/19/2020] [Revised: 04/16/2021] [Accepted: 04/23/2021] [Indexed: 06/12/2023]
Abstract
Bacteria often respond to dynamic soil environment through the secretion of extracellular polymeric substances (EPS). The EPS modifies cell surface properties and soil pore-scale hydration status, which in turn, influences bacteria transport in soil. However, the effect of soil particle size and EPS-mediated surface properties on bacterial transport in the soil is not well understood. In this study, the simultaneous impacts of EPS and collector size on Escherichia coli (E. coli) transport and deposition in a sand column were investigated. E. coli transport experiments were carried out under steady-state flow in saturated columns packed with quartz sand with different size ranges, including 0.300-0.425 mm (sand-I), 0.212-0.300 mm (sand-II), 0.106-0.150 mm (sand-III) and 0.075-0.106 mm (sand-IV). Bacterial retention increased with decreasing sand collector size, suggesting that straining played an important role in fine-textured media. Both experiment and simulation results showed a clear drop in the retention rate of the bacterial population with the presence of additional EPS (200 mg L-1) (EPS+). The inhibited retention of cells in sand columns under EPS+ scenario was likely attributed to enhanced bacteria hydrophilicity and electrostatic repulsion between cells and sand particles as well as reduced straining. Calculations of the extended Derjaguin-Landau-Verwey-Overbeek (XDLVO) interactions energies revealed that high repulsive energy barrier existed between bacterial cells and sand particles in EPS+ environment, primarily due to high repulsive electrostatic force and Lewis acid-base force, as well as low attractive Lifshitz-van der Waals force, which retarded bacterial population deposition. Steric stabilization of EPS would also prevent the approaching of cells close to the quartz surface and thereby hinder cell attachment. This study was the first to show that EPS reduced bacterial straining in saturated porous media. These findings provide new insight into the functional effects of extrinsic EPS on bacterial transport behavior in the saturated soil environment, e.g., aquifers.
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Affiliation(s)
- Mengya Du
- Department of Soil and Water Sciences, China Agricultural University, Beijing 100193, China
| | - Lin Wang
- Department of Soil and Water Sciences, China Agricultural University, Beijing 100193, China
| | - Ali Ebrahimi
- Department of Civil and Environmental Engineering, Massachusetts Institute of Technology, Cambridge, MA 02139, USA
| | - Guowei Chen
- Department of Municipal Engineering, Hefei University of Technology, Hefei, Anhui 230009, China
| | - Shangyi Shu
- Department of Soil and Water Sciences, China Agricultural University, Beijing 100193, China
| | - Kun Zhu
- Department of Soil and Water Sciences, China Agricultural University, Beijing 100193, China
| | - Chongyang Shen
- Department of Soil and Water Sciences, China Agricultural University, Beijing 100193, China
| | - Baoguo Li
- Department of Soil and Water Sciences, China Agricultural University, Beijing 100193, China
| | - Gang Wang
- Department of Soil and Water Sciences, China Agricultural University, Beijing 100193, China.
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Saleem M, Malik S, Mehwish HM, Ali MW, Hussain N, Khurshid M, Rajoka MSR, Chen Y. Isolation and functional characterization of exopolysaccharide produced by Lactobacillus plantarum S123 isolated from traditional Chinese cheese. Arch Microbiol 2021; 203:3061-3070. [PMID: 33791833 DOI: 10.1007/s00203-021-02291-w] [Citation(s) in RCA: 17] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/28/2020] [Revised: 03/15/2021] [Accepted: 03/17/2021] [Indexed: 12/23/2022]
Abstract
During the past few years, there are growing interests in the potential use of exopolysaccharide (EPS) in the food industry as an efficient biopolymer because of its exceptional biological features. Therefore, the aim of the present study is EPS production by Lactobacillus Plantarum S123 (S123 EPS), its partial structural and biopotential characterization. The results from this study suggested that the major portion of S123 EPS has an amorphous sponge-like structure with partial crystalline nature. The FTIR and NMR results suggested that the S123 EPS consists of carbonyl and hydroxyl groups, respectively. Furthermore, the results of technological as well as biotechnological characterization suggested that the S123 EPS was exhibited excellent antibacterial activity against Gram-positive (7.2 mm) and Gram-negative bacteria (11.5 mm), DPPH radical scavenging activity (> 65%), water holding capacity (326.6 ± 0.5%), oil holding capacity (995.3 ± 0.2%), flocculation (89.5 ± 0.6%), and emulsifying (80.1 ± 1.1%) activities. Overall, the present results suggested that due to the highly porous structure and efficient biotechnological potential, S123 EPS from Lactobacillus plantarum S123 (L. plantarum S123) can be used in the functional food product.
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Affiliation(s)
- Muhammad Saleem
- Institute for Advanced Study, Shenzhen University, Nanshan District, Shenzhen, 518060, Guangdong, China.,Department of Optoelectronic Science and Technology, Shenzhen University, Shenzhen, 518060, People's Republic of China.,Department of Chemistry, University of Kotli, Kotli, Azad Jammu and Kashmir, Pakistan
| | - Samiullah Malik
- School of Basic Medicine, Health Science Center, Shenzhen University, Shenzhen, 518060, People's Republic of China
| | - Hafiza Mahreen Mehwish
- School of Basic Medicine, Health Science Center, Shenzhen University, Shenzhen, 518060, People's Republic of China
| | - Muhammad Waqas Ali
- Institute for Advanced Study, Shenzhen University, Nanshan District, Shenzhen, 518060, Guangdong, China
| | - Nazim Hussain
- Centre for Applied Molecular Biology (CAMB), University of the Punjab, Lahore, 53700, Pakistan
| | - Mohsin Khurshid
- Department of Microbiology, Government College University, Faisalabad, Pakistan
| | - Muhammad Shahid Riaz Rajoka
- School of Basic Medicine, Health Science Center, Shenzhen University, Shenzhen, 518060, People's Republic of China. .,Food and Feed Immunology Group, Graduate School of Agricultural Science, Tohoku University, Sendai, 980-8572, Japan.
| | - Yougen Chen
- Institute for Advanced Study, Shenzhen University, Nanshan District, Shenzhen, 518060, Guangdong, China.
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Chouchane H, Najjari A, Neifar M, Cherif H, Askri R, Naili F, Ouzari HI, Cherif A. Unravelling the characteristics of a heteropolysaccharide-protein from an Haloarchaeal strain with flocculation effectiveness in heavy metals and dyes removal. ENVIRONMENTAL TECHNOLOGY 2020; 41:2180-2195. [PMID: 30517064 DOI: 10.1080/09593330.2018.1556742] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/25/2018] [Accepted: 12/03/2018] [Indexed: 06/09/2023]
Abstract
The production, characterization and potential application in heavy metals and dyes removal of a novel heteropolysaccharide-protein named, gpHb, produced by an Haloarchaeal strain Halogeometricum borinquense strain A52 were investigated. The highest gpHb yield of 13.96 ± 0.32 g/L was produced under optimized conditions by response surface methodology. We focused on the characteristics and flocculation performance of gpHb. An important attribute of protein with 16 protein types identified that occupied a total content of 50.2% in the gpHb. Additionally, carbohydrate that occupied 30.4% of the total bioflocculant content consisted of three monosaccharides. Fourier transform-infrared spectroscopy indicated the presence of carboxyl, hydroxyl, amine, amide, and sulphate groups. To further study flocculation activities, factors such as bioflocculant dosage, temperature, pH, salinity and cations addition were tested. In comparison to the chemical flocculant polyaluminium chloride, gpHb maintain high activity at large range of salinity and its flocculation activity was higher on both sides of pH 7. Addition of trivalent cation mainly Fe3+ enhances the flocculating rate indicating that the bioflocculant is negatively charged. Its practical applicability was established for heavy metals and dyes removal from saline aqueous solutions. The highest removal efficiency was observed with Cr3+ (91.4%) and Ni2+ (89.60%) and with basic blue 3 (83.8%) and basic red (78.6%). The excellent flocculation activity of gpHb under saline condition suggests its potential industrial utility for treatment of textile and tannery wastewaters.
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Affiliation(s)
- Habib Chouchane
- ISBST, LR11-ES31 BVBGR, Biotechpole Sidi Thabet, Univ. Manouba, Ariana, Tunisia
| | - Afef Najjari
- Faculté des Sciences de Tunis, LR03ES03 Laboratoire de Microbiologie et Biomolécules Actives, Université Tunis El Manar, Tunis, Tunisia
| | - Mohamed Neifar
- ISBST, LR11-ES31 BVBGR, Biotechpole Sidi Thabet, Univ. Manouba, Ariana, Tunisia
| | - Hanen Cherif
- ISBST, LR11-ES31 BVBGR, Biotechpole Sidi Thabet, Univ. Manouba, Ariana, Tunisia
| | - Refka Askri
- ISBST, LR11-ES31 BVBGR, Biotechpole Sidi Thabet, Univ. Manouba, Ariana, Tunisia
| | - Fatma Naili
- ISBST, LR11-ES31 BVBGR, Biotechpole Sidi Thabet, Univ. Manouba, Ariana, Tunisia
| | - Hadda Imene Ouzari
- Faculté des Sciences de Tunis, LR03ES03 Laboratoire de Microbiologie et Biomolécules Actives, Université Tunis El Manar, Tunis, Tunisia
| | - Ameur Cherif
- ISBST, LR11-ES31 BVBGR, Biotechpole Sidi Thabet, Univ. Manouba, Ariana, Tunisia
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Ma L, Liang J, Wang S, Yang B, Chen M, Liu Y. Production of a bioflocculant from Klebsiella sp. OS-1 using brewery wastewater as a source. ENVIRONMENTAL TECHNOLOGY 2019; 40:44-52. [PMID: 28877651 DOI: 10.1080/09593330.2017.1377770] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/31/2017] [Accepted: 09/04/2017] [Indexed: 06/07/2023]
Abstract
This study evaluated the potential of bioflocculant production from a Klebsiella strain using brewery wastewater as nutrients. The bioflocculant named OS-1B produced by Klebsiella sp. OS-1 exhibited a good flocculating activity to kaolin clay suspension (around 95%), when the diluted brewery wastewater with 7.2 mg/L total nitrogen and 1013 mg/L CODCr was used as a nitrogen source. Glucose (15 g/L) is the most favorable carbon source for Klebsiella sp. OS-1 in bioflocculant production from brewery wastewater. The yielded bioflocculant is pH tolerant and thermally stable, suggesting its good industrial potential. OS-1B mainly comprises polysaccharide (69.4%) and protein (24.5%). Fourier-transform infrared spectra indicate the presence of hydroxyl, carboxyl, esters and amino groups in the bioflocculant molecules. Combined with the results of zeta potential measurements, bridging is suggested as the main flocculation mechanism for OS-1B flocculation with kaolin. Overall, brewery wastewater can be used as a substrate to produce bioflocculants.
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Affiliation(s)
- Lili Ma
- a School of Chemistry and Chemical Engineering , Southwest Petroleum University , Chengdu , People's Republic of China
| | - Jingjing Liang
- a School of Chemistry and Chemical Engineering , Southwest Petroleum University , Chengdu , People's Republic of China
| | - Shanyi Wang
- a School of Chemistry and Chemical Engineering , Southwest Petroleum University , Chengdu , People's Republic of China
- b Hangxiang Nine-year Compulsory Education School , Ziyang , People's Republic of China
| | - Bing Yang
- a School of Chemistry and Chemical Engineering , Southwest Petroleum University , Chengdu , People's Republic of China
| | - Mingyan Chen
- a School of Chemistry and Chemical Engineering , Southwest Petroleum University , Chengdu , People's Republic of China
| | - Yucheng Liu
- a School of Chemistry and Chemical Engineering , Southwest Petroleum University , Chengdu , People's Republic of China
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11
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Srivastava A, Seo SH, Ko SR, Ahn CY, Oh HM. Bioflocculation in natural and engineered systems: current perspectives. Crit Rev Biotechnol 2018; 38:1176-1194. [DOI: 10.1080/07388551.2018.1451984] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/03/2023]
Affiliation(s)
- Ankita Srivastava
- Cell Factory Research Center, Korea Research Institute of Bioscience and Biotechnology, Daejeon, Republic of Korea
| | - Seong-Hyun Seo
- Cell Factory Research Center, Korea Research Institute of Bioscience and Biotechnology, Daejeon, Republic of Korea
| | - So-Ra Ko
- Cell Factory Research Center, Korea Research Institute of Bioscience and Biotechnology, Daejeon, Republic of Korea
| | - Chi-Yong Ahn
- Cell Factory Research Center, Korea Research Institute of Bioscience and Biotechnology, Daejeon, Republic of Korea
| | - Hee-Mock Oh
- Cell Factory Research Center, Korea Research Institute of Bioscience and Biotechnology, Daejeon, Republic of Korea
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12
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Functional characterization and biotechnological potential of exopolysaccharide produced by Lactobacillus rhamnosus strains isolated from human breast milk. Lebensm Wiss Technol 2018. [DOI: 10.1016/j.lwt.2017.11.034] [Citation(s) in RCA: 68] [Impact Index Per Article: 11.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/21/2023]
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13
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Ntozonke N, Okaiyeto K, Okoli AS, Olaniran AO, Nwodo UU, Okoh AI. A Marine Bacterium, Bacillus sp. Isolated from the Sediment Samples of Algoa Bay in South Africa Produces a Polysaccharide-Bioflocculant. INTERNATIONAL JOURNAL OF ENVIRONMENTAL RESEARCH AND PUBLIC HEALTH 2017; 14:ijerph14101149. [PMID: 28961180 PMCID: PMC5664650 DOI: 10.3390/ijerph14101149] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 09/01/2017] [Revised: 09/21/2017] [Accepted: 09/25/2017] [Indexed: 11/16/2022]
Abstract
Bioflocculants mediate the removal of suspended particles from solution and the efficiency of flocculation is dependent on the characteristics of the flocculant. Apart from the merits of biodegradability and harmlessness, bioflocculants could be viable as industrially relevant flocculants as they are a renewable resource. Additionally, the shortcomings associated with the conventionally used flocculants such as aluminium salts and acrylamide polymers, which include dementia and cancer, highlight more the need to use bioflocculants as an alternative. Consequently, in this study a marine sediment bacterial isolate was screened for bioflocculant production. Basic local alignment search tools (BLAST) analysis of 16S ribosomal deoxyribonucleic acid (rDNA) sequence of the bacterial isolate showed 98% similarity to Bacillus thuringiensis MR-R1. The bacteria produced bioflocculant optimally with inoculum size (4% v/v) (85%), glucose (85.65%) and mixed nitrogen source (urea, ammonium chloride and yeast extract) (75.9%) and the divalent cation (Ca2+) (62.3%). Under optimal conditions, a maximum flocculating activity of over 85% was attained after 60 h of cultivation. The purified polysaccharide-bioflocculant flocculated optimally at alkaline pH 12 (81%), in the presence of Mn2+ (73%) and Ca2+ (72.8%). The high flocculation activity shown indicates that the bioflocculant may contend favourably as an alternative to the conventionally used flocculants in water treatment.
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Affiliation(s)
- Ncedo Ntozonke
- SAMRC Microbial Water Quality Monitoring Centre, University of Fort Hare, Private Bag X1314, Alice 5700, South Africa.
- Applied and Environmental Microbiology Research Group (AEMREG), Department of Biochemistry and Microbiology, University of Fort Hare, Private Bag X1314, Alice 5700, South Africa.
| | - Kunle Okaiyeto
- SAMRC Microbial Water Quality Monitoring Centre, University of Fort Hare, Private Bag X1314, Alice 5700, South Africa.
- Applied and Environmental Microbiology Research Group (AEMREG), Department of Biochemistry and Microbiology, University of Fort Hare, Private Bag X1314, Alice 5700, South Africa.
| | - Arinze S Okoli
- GenØK-Centre for Biosafety, Forskningsparken i Breivika, Postboks 6418, 9294 Tromsø, Norway.
| | - Ademola O Olaniran
- Department of Microbiology, School of Life Sciences, University of KwaZulu-Natal, Private Bag X54001, Durban 4000, South Africa.
| | - Uchechukwu U Nwodo
- SAMRC Microbial Water Quality Monitoring Centre, University of Fort Hare, Private Bag X1314, Alice 5700, South Africa.
- Applied and Environmental Microbiology Research Group (AEMREG), Department of Biochemistry and Microbiology, University of Fort Hare, Private Bag X1314, Alice 5700, South Africa.
| | - Anthony I Okoh
- SAMRC Microbial Water Quality Monitoring Centre, University of Fort Hare, Private Bag X1314, Alice 5700, South Africa.
- Applied and Environmental Microbiology Research Group (AEMREG), Department of Biochemistry and Microbiology, University of Fort Hare, Private Bag X1314, Alice 5700, South Africa.
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14
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Abd El-Salam AE, Abd-El-Haleem D, Youssef AS, Zaki S, Abu-Elreesh G, El-Assar SA. Isolation, characterization, optimization, immobilization and batch fermentation of bioflocculant produced by Bacillus aryabhattai strain PSK1. J Genet Eng Biotechnol 2017; 15:335-344. [PMID: 30647672 PMCID: PMC6296622 DOI: 10.1016/j.jgeb.2017.07.002] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/29/2017] [Revised: 06/15/2017] [Accepted: 07/03/2017] [Indexed: 11/18/2022]
Abstract
Among others, isolate PSK1 was selected and identified by 16 S rDNA sequencing as Bacillus aryabhattai. Growth optimization of PSK1 and physicochemical parameters affected bioflocculant production was carried out by Plackett-Burman design and resulted in increasing in the activity by 4.5%. Bioflocculant production by entrapped and adsorbed immobilized microbial cells was performed using different techniques and revealed enhancement in the activity in particular with pumice adsorption. HPLC analysis of sugars and amino acids composition, FTIR and the effect of different factors on the purified PSK1 biopolymer such as presence of cations, thermal stability, pH range and clay concentration was carried out. Scanning electron microscopy (SEM) of free, immobilized cells, PSK1 bioflocculant and formed flocs were performed. The results revealed that bioflocculant PSK1 is mainly glycoprotein consists of glucose and rhamnose with a large number of amino acids in which arginine and phenylalanine were the major. SEM analysis demonstrated that PSK1 have a clear crystalline rod shaped structure. FTIR spectrum reported the presence of hydroxyl and amino groups which are preferred in flocculation process. PSK1 was soluble in water and insoluble in all other tested organic solvents, while it was thermally stable from 40 to 80 °C. Among examined cations, CaCl2 was the best coagulant. The maximum flocculation activity of the PSK1 recorded at 50 °C (92.8%), pH 2.0 (94.56%) with clay concentration range 5-9 g/l. To obtain a large amount of PSK1 bioflocculant with high flocculating activity, batch fermentation was employed. The results recorded ∼6 g/l yield after 24 h of fermentation.
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Affiliation(s)
- Ayat E. Abd El-Salam
- Botany and Microbiology Department, Faculty of Science, Alexandria University, Alexandria, Egypt
| | - Desouky Abd-El-Haleem
- Environmental Biotechnology Department, Genetic Engineering and Biotechnology Research Institute, City of Scientific Research and Technological Applications, 21934 Burgelarab, Alexandria, Egypt
- Corresponding author.
| | - Amany S. Youssef
- Botany and Microbiology Department, Faculty of Science, Alexandria University, Alexandria, Egypt
| | - Sahar Zaki
- Environmental Biotechnology Department, Genetic Engineering and Biotechnology Research Institute, City of Scientific Research and Technological Applications, 21934 Burgelarab, Alexandria, Egypt
| | - Gadallah Abu-Elreesh
- Environmental Biotechnology Department, Genetic Engineering and Biotechnology Research Institute, City of Scientific Research and Technological Applications, 21934 Burgelarab, Alexandria, Egypt
| | - Samy A. El-Assar
- Botany and Microbiology Department, Faculty of Science, Alexandria University, Alexandria, Egypt
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15
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Guo H, Hong C, Zheng B, Lu F, Jiang D, Qin W. Bioflocculants' production in a biomass-degrading bacterium using untreated corn stover as carbon source and use of bioflocculants for microalgae harvest. BIOTECHNOLOGY FOR BIOFUELS 2017; 10:306. [PMID: 29270220 PMCID: PMC5738095 DOI: 10.1186/s13068-017-0987-6] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/12/2017] [Accepted: 12/01/2017] [Indexed: 05/19/2023]
Abstract
BACKGROUND Bioflocculation has been developed as a cost-effective and environment-friendly method to harvest multiple microalgae. However, the high production cost of bioflocculants makes it difficult to scale up. In the current study, low-cost bioflocculants were produced from untreated corn stover by a biomass-degrading bacterium Pseudomonas sp. GO2. RESULTS Pseudomonas sp. GO2 showed excellent production ability of bioflocculants through directly hydrolyzing various biomasses. The untreated corn stover was selected as carbon source for bioflocculants' production due to its highest flocculating efficiency compared to that when using other biomasses as carbon source. The effects of fermentation parameters on bioflocculants' production were optimized via response surface methodology. According to the optimal model, an ideal flocculating efficiency of 99.8% was obtained with the fermentation time of 130.46 h, initial pH of 7.46, and biomass content of 0.64%. The relative importance of carboxymethyl cellulase and xylanase accounted for 51.8% in the process of bioflocculants' production by boosted regression tree analysis, further indicating that the bioflocculants were mainly from the hydrolysates of biomass. Biochemical analysis showed that it contained 59.0% polysaccharides with uronic acid (34.2%), 32.1% protein, and 6.1% nucleic acid in the bioflocculants, which had an average molecular weight as 1.33 × 106 Da. In addition, the bioflocculants showed the highest flocculating efficiency at a concentration of 12.5 mg L-1 and were stable over broad ranges of pH and temperature. The highest flocculating efficiencies obtained for Chlorella zofingiensis and Neochloris oleoabundans were 77.9 and 88.9%, respectively. CONCLUSIONS The results indicated that Pseudomonas sp. GO2 can directly utilize various untreated lignocellulolytic biomasses to produce low-cost bioflocculants, which showed the high efficiency to harvest two green microalgae in a low GO2 fermentation broth/algal culture ratio.
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Affiliation(s)
- Haipeng Guo
- Department of Biology, Lakehead University, Thunder Bay, ON P7B 5E1 Canada
- State Key Laboratory of Plant Physiology and Biochemistry, College of Life Sciences, Zhejiang University, Hangzhou, 310058 China
| | - Chuntao Hong
- Academy of Agricultural Sciences of Ningbo City, Ningbo, 315040 China
| | - Bingsong Zheng
- State Key Laboratory of Subtropical Silviculture, Zhejiang A & F University, Hangzhou, 311300 China
| | - Fan Lu
- School of Biological Engineering, Hubei University of Technology, Wuhan, 430068 China
| | - Dean Jiang
- State Key Laboratory of Plant Physiology and Biochemistry, College of Life Sciences, Zhejiang University, Hangzhou, 310058 China
| | - Wensheng Qin
- Department of Biology, Lakehead University, Thunder Bay, ON P7B 5E1 Canada
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16
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Okaiyeto K, Nwodo UU, Okoli SA, Mabinya LV, Okoh AI. Implications for public health demands alternatives to inorganic and synthetic flocculants: bioflocculants as important candidates. Microbiologyopen 2016; 5:177-211. [PMID: 26914994 PMCID: PMC4831466 DOI: 10.1002/mbo3.334] [Citation(s) in RCA: 47] [Impact Index Per Article: 5.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/29/2015] [Revised: 11/05/2015] [Accepted: 11/24/2015] [Indexed: 12/11/2022] Open
Abstract
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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Affiliation(s)
- Kunle Okaiyeto
- SAMRC Microbial Water Quality Monitoring Centre, University of Fort Hare, Alice, 5700, South Africa.,Applied and Environmental Microbiology Research Group (AEMREG), Department of Biochemistry and Microbiology, University of Fort Hare, Alice, 5700, South Africa
| | - Uchechukwu U Nwodo
- SAMRC Microbial Water Quality Monitoring Centre, University of Fort Hare, Alice, 5700, South Africa.,Applied and Environmental Microbiology Research Group (AEMREG), Department of Biochemistry and Microbiology, University of Fort Hare, Alice, 5700, South Africa
| | - Stanley A Okoli
- GenØK - Centre for Biosafety, Science Park, University of Tromsø, Tromsø, 9291, Norway
| | - Leonard V Mabinya
- SAMRC Microbial Water Quality Monitoring Centre, University of Fort Hare, Alice, 5700, South Africa.,Applied and Environmental Microbiology Research Group (AEMREG), Department of Biochemistry and Microbiology, University of Fort Hare, Alice, 5700, South Africa
| | - Anthony I Okoh
- SAMRC Microbial Water Quality Monitoring Centre, University of Fort Hare, Alice, 5700, South Africa.,Applied and Environmental Microbiology Research Group (AEMREG), Department of Biochemistry and Microbiology, University of Fort Hare, Alice, 5700, South Africa
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17
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Okaiyeto K, Nwodo UU, Mabinya LV, Okoli AS, Okoh AI. Evaluation of flocculating performance of a thermostable bioflocculant produced by marine Bacillus sp. ENVIRONMENTAL TECHNOLOGY 2016; 37:1829-1842. [PMID: 26797258 DOI: 10.1080/09593330.2015.1133717] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/05/2023]
Abstract
This study assessed the bioflocculant (named MBF-W7) production potential of a bacterial isolate obtained from Algoa Bay, Eastern Cape Province of South Africa. The 16S ribosomal deoxyribonucleic acids gene sequence analysis showed 98% sequence similarity to Bacillus licheniformis strain W7. Optimum culture conditions for MBF-W7 production include 5% (v/v) inoculum size, maltose and NH4NO3 as carbon and nitrogen sources of choice, medium pH of 6 as the initial pH of the growth medium. Under these optimal conditions, maximum flocculating activity of 94.9% was attained after 72 h of cultivation. Chemical composition analyses showed that the purified MBF-W7 was a glycoprotein which was predominantly composed of polysaccharides 73.7% (w/w) and protein 6.2% (w/w). Fourier transform infrared spectroscopy revealed the presence of hydroxyl, carboxyl and amino groups as the main functional groups identified in the bioflocculant molecules. Thermogravimetric analyses showed the thermal decomposition profile of MBF-W7. Scanning electron microscopy imaging revealed that bridging played an important role in flocculation. MBF-W7 exhibited excellent flocculating activity for kaolin clay suspension at 0.2 mg/ml over a wide pH range of 3-11; with the maximal flocculation rate of 85.8% observed at pH 3 in the presence of Mn(2+). It maintained and retained high flocculating activity of over 70% after heating at 100°C for 60 min. MBF-W7 showed good turbidity removal potential (86.9%) and chemical oxygen demand reduction efficiency (75.3%) in Tyume River. The high flocculating rate of MBF-W7 makes it an attractive candidate to replace chemical flocculants utilized in water treatment.
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Affiliation(s)
- Kunle Okaiyeto
- a South Africa Medical Research Council (SAMRC), Microbial Water Quality Monitoring Centre , University of Fort Hare , Alice , South Africa
- b Applied and Environmental Microbiology Research Group, Department of Biochemistry and Microbiology , University of Fort Hare , Alice , South Africa
| | - Uchechukwu U Nwodo
- a South Africa Medical Research Council (SAMRC), Microbial Water Quality Monitoring Centre , University of Fort Hare , Alice , South Africa
- b Applied and Environmental Microbiology Research Group, Department of Biochemistry and Microbiology , University of Fort Hare , Alice , South Africa
| | - Leonard V Mabinya
- a South Africa Medical Research Council (SAMRC), Microbial Water Quality Monitoring Centre , University of Fort Hare , Alice , South Africa
- b Applied and Environmental Microbiology Research Group, Department of Biochemistry and Microbiology , University of Fort Hare , Alice , South Africa
| | - Arinze S Okoli
- c GenØK Centre for Biosafety , Forskningsparken i Breivika , Tromsø , Norway
| | - Anthony I Okoh
- a South Africa Medical Research Council (SAMRC), Microbial Water Quality Monitoring Centre , University of Fort Hare , Alice , South Africa
- b Applied and Environmental Microbiology Research Group, Department of Biochemistry and Microbiology , University of Fort Hare , Alice , South Africa
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18
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Okaiyeto K, Nwodo UU, Mabinya LV, Okoli AS, Okoh AI. Characterization of a Bioflocculant (MBF-UFH) Produced by Bacillus sp. AEMREG7. Int J Mol Sci 2015; 16:12986-3003. [PMID: 26062133 PMCID: PMC4490482 DOI: 10.3390/ijms160612986] [Citation(s) in RCA: 42] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/29/2015] [Revised: 05/10/2015] [Accepted: 05/11/2015] [Indexed: 01/28/2023] Open
Abstract
A bioflocculant named MBF-UFH produced by a Bacillus species isolated from sediment samples of Algoa Bay of the Eastern Cape Province of South Africa was characterized. The bacterial identification was through 16S rDNA sequencing; nucleotide sequences were deposited in GenBank as Bacillus sp. AEMREG7 with Accession Number KP659187. The production of the bioflocculant was observed to be closely associated with cell growth. The bioflocculant had the highest flocculating activity of 83.2% after 72 h of cultivation, and approximately 1.6 g of purified MBF-UFH was recovered from 1 L of fermentation broth. Its chemical analyses indicated that it is a glycoprotein composed of polysaccharide (76%) and protein (14%). Fourier transform infrared spectroscopy (FTIR) revealed that it consisted of hydroxyl, amide, carboxyl and methoxyl as the functional moieties. Scanning electron microscopy (SEM) revealed the amorphous structure of MBF-UFH and flocculated kaolin clay particles. The maximum flocculating activity of 92.6% against kaolin clay suspension was achieved at 0.3 mg/mL over pH ranges of 3-11 with the peak flocculating rate at pH 8 in the presence of MgCl2. The bioflocculant retained high flocculating activity of 90% after heating at 100 °C for 1 h. MBF-UFH appears to have immense potential as an alternative to conventional chemical flocculants.
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Affiliation(s)
- Kunle Okaiyeto
- South Africa-Medical Research Council (SA-MRC), Microbial Water Quality Monitoring Centre, University of Fort Hare, 5700 Alice, South Africa.
- Applied and Environmental Microbiology Research Group, Department of Biochemistry and Microbiology, University of Fort Hare, 5700 Alice, South Africa.
| | - Uchechukwu U Nwodo
- South Africa-Medical Research Council (SA-MRC), Microbial Water Quality Monitoring Centre, University of Fort Hare, 5700 Alice, South Africa.
- Applied and Environmental Microbiology Research Group, Department of Biochemistry and Microbiology, University of Fort Hare, 5700 Alice, South Africa.
| | - Leonard V Mabinya
- South Africa-Medical Research Council (SA-MRC), Microbial Water Quality Monitoring Centre, University of Fort Hare, 5700 Alice, South Africa.
- Applied and Environmental Microbiology Research Group, Department of Biochemistry and Microbiology, University of Fort Hare, 5700 Alice, South Africa.
| | - Arinze S Okoli
- GenØK-Centre for Biosafety, Forskningsparken i Breivika, Postboks 6418, 9294 Tromsø, Norway.
| | - Anthony I Okoh
- South Africa-Medical Research Council (SA-MRC), Microbial Water Quality Monitoring Centre, University of Fort Hare, 5700 Alice, South Africa.
- Applied and Environmental Microbiology Research Group, Department of Biochemistry and Microbiology, University of Fort Hare, 5700 Alice, South Africa.
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19
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Tang W, Song L, Li D, Qiao J, Zhao T, Zhao H. Production, characterization, and flocculation mechanism of cation independent, pH tolerant, and thermally stable bioflocculant from Enterobacter sp. ETH-2. PLoS One 2014; 9:e114591. [PMID: 25485629 PMCID: PMC4259340 DOI: 10.1371/journal.pone.0114591] [Citation(s) in RCA: 58] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/17/2014] [Accepted: 11/09/2014] [Indexed: 11/18/2022] Open
Abstract
Synthetic high polymer flocculants, frequently utilized for flocculating efficiency and low cost, recently have been discovered as producing increased risk to human health and the environment. Development of a more efficient and environmentally sound alternative flocculant agent is investigated in this paper. Bioflocculants are produced by microorganisms and may exhibit a high rate of flocculation activity. The bioflocculant ETH-2, with high flocculating activity (2849 mg Kaolin particle/mg ETH-2), produced by strain Enterobacter sp. isolated from activated sludge, was systematically investigated with regard to its production, characterization, and flocculation mechanism. Analyses of microscopic observation, zeta potential and ETH-2 structure demonstrates the bridging mechanism, as opposed to charge neutralization, was responsible for flocculation of the ETH-2. ETH-2 retains high molecular weight (603 to 1820 kDa) and multi-functional groups (hydroxyl, amide and carboxyl) that contributed to flocculation. Polysaccharides mainly composed of mannose, glucose, and galactose, with a molar ratio of 1∶2.9∶9.8 were identified as the active constituents in bioflocculant. The structure of the long backbone with active sites of polysaccharides was determined as a primary basis for the high flocculation activity. Bioflocculant ETH-2 is cation independent, pH tolerant, and thermally stable, suggesting a potential fit for industrial application.
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Affiliation(s)
- Wei Tang
- Research Center of Environmental Microbiology and Ecology, Chongqing Institute of Green and Intelligent Technology, Chinese Academy of Science, Chongqing, 400714, China
| | - Liyan Song
- Research Center of Environmental Microbiology and Ecology, Chongqing Institute of Green and Intelligent Technology, Chinese Academy of Science, Chongqing, 400714, China
- Key Laboratory of Reservoir Aquatic Environment, Chinese Academy of Sciences, Chongqing Institute of Green and Intelligent Technology, Chinese Academy of Sciences, Chongqing, 400714, China
- * E-mail:
| | - Dou Li
- Research Center of Environmental Microbiology and Ecology, Chongqing Institute of Green and Intelligent Technology, Chinese Academy of Science, Chongqing, 400714, China
- Key Laboratory of Reservoir Aquatic Environment, Chinese Academy of Sciences, Chongqing Institute of Green and Intelligent Technology, Chinese Academy of Sciences, Chongqing, 400714, China
| | - Jing Qiao
- Research Center of Environmental Microbiology and Ecology, Chongqing Institute of Green and Intelligent Technology, Chinese Academy of Science, Chongqing, 400714, China
| | - Tiantao Zhao
- School of Chemistry and Chemical Engineering, Chongqing University of Technology, Chongqing, 400054, China
| | - Heping Zhao
- Ministry of Education, Key Lab of Environmental Remediation and Ecosystem Health, College of Environmental and Resource Science, Zhejiang University, Hangzhou, 310058, China
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20
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Salehizadeh H, Yan N. Recent advances in extracellular biopolymer flocculants. Biotechnol Adv 2014; 32:1506-22. [DOI: 10.1016/j.biotechadv.2014.10.004] [Citation(s) in RCA: 87] [Impact Index Per Article: 8.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/16/2014] [Revised: 10/02/2014] [Accepted: 10/07/2014] [Indexed: 10/24/2022]
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21
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Yin YJ, Tian ZM, Tang W, Li L, Song LY, McElmurry SP. Production and characterization of high efficiency bioflocculant isolated from Klebsiella sp. ZZ-3. BIORESOURCE TECHNOLOGY 2014; 171:336-342. [PMID: 25218206 DOI: 10.1016/j.biortech.2014.08.094] [Citation(s) in RCA: 30] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/23/2014] [Revised: 08/21/2014] [Accepted: 08/22/2014] [Indexed: 06/03/2023]
Abstract
In this study, a new bioflocculant (ZZ-3) is isolated and evaluated. This novel flocculant was derived Klebsiella, which was identified by 16S rDNA sequencing as well as biochemical and physiological analyses. The composition of ZZ-3 was found to be 84.6% polysaccharides and 6.1% protein. More specifically, the amount (moles) of the polysaccharides rhamnose, mannose, and galactose were found to be 6.48, 2.47, and 1.74 greater than glucose, respectively. Results show ZZ-3 has a relatively high molecular weight (603-1820 kDa) and contains many functional groups (hydroxyl, amide, carboxyl, and methoxyl) that likely contribute to flocculation. The results of microscopic observation, zeta potential measurements, and ZZ-3 bioflocculant structure suggested that bridging was the main mechanism for flocculation with kaolin. Based on a high flocculation efficiency, thermal stability, pH tolerance and the ability to flocculate without additional cations, ZZ-3 shows potential for industrial application.
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Affiliation(s)
- Ya-Jie Yin
- Environmental Microbiology and Ecology Research Center, Chongqing Institute of Green and Intelligent Technology, Chinese Academy of Sciences, Chongqing 400714, PR China
| | - Zun-Ming Tian
- Shanghai Information Center for Life Sciences, Shanghai Institute of Biological Sciences, Chinese Academy of Science, Shanghai 200031, PR China
| | - Wei Tang
- Environmental Microbiology and Ecology Research Center, Chongqing Institute of Green and Intelligent Technology, Chinese Academy of Sciences, Chongqing 400714, PR China
| | - Lei Li
- Environmental Microbiology and Ecology Research Center, Chongqing Institute of Green and Intelligent Technology, Chinese Academy of Sciences, Chongqing 400714, PR China
| | - Li-Yan Song
- Environmental Microbiology and Ecology Research Center, Chongqing Institute of Green and Intelligent Technology, Chinese Academy of Sciences, Chongqing 400714, PR China; Key Laboratory of Reservoir Aquatic Environment, Chongqing Institute of Green and Intelligent Technology, Chinese Academy of Sciences, Chongqing 400714, PR China.
| | - Shawn P McElmurry
- Department of Civil & Environmental Engineering, Wayne State University, Detroit, MI 48202, USA
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22
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More TT, Yadav JSS, Yan S, Tyagi RD, Surampalli RY. Extracellular polymeric substances of bacteria and their potential environmental applications. JOURNAL OF ENVIRONMENTAL MANAGEMENT 2014; 144:1-25. [PMID: 24907407 DOI: 10.1016/j.jenvman.2014.05.010] [Citation(s) in RCA: 416] [Impact Index Per Article: 41.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/14/2013] [Revised: 05/02/2014] [Accepted: 05/11/2014] [Indexed: 05/06/2023]
Abstract
Biopolymers are considered a potential alternative to conventional chemical polymers because of their ease of biodegradability, high efficiency, non-toxicity and non-secondary pollution. Recently, extracellular polymeric substances (EPS, biopolymers produced by the microorganisms) have been recognised by many researchers as a potential flocculent for their applications in various water, wastewater and sludge treatment processes. In this context, literature information on EPS is widely dispersed and is very scarce. Thus, this review marginalizes various studies conducted so far about EPS nature-production-recovery, properties, environmental applications and moreover, critically examines future research needs and advanced application prospective of the EPS. One of the most important aspect of chemical composition and structural details of different moieties of EPS in terms of carbohydrates, proteins, extracellular DNA, lipid and surfactants and humic substances are described. These chemical characteristics of EPS in relation to formation and properties of microbial aggregates as well as degradation of EPS in the matrix (biomass, flocs etc) are analyzed. The important engineering properties (based on structural characteristics) such as adsorption, biodegradability, hydrophilicity/hydrophobicity of EPS matrix are also discussed in details. Different aspects of EPS production process such as bacterial strain maintenance; inoculum and factors affecting EPS production were presented. The important factors affecting EPS production include growth phase, carbon and nitrogen sources and their ratio, role of other nutrients (phosphorus, micronutrients/trace elements, and vitamins), impact of pH, temperature, metals, aerobic versus anaerobic conditions and pure and mixed culture. The production of EPS in high concentration with high productivity is essential due to economic reasons. Therefore, the knowledge about all the aspects of EPS production (listed above) is highly essential to formulate a logical and scientific basis for the research and industrial activities. One of the very important issues in the production/application/biodegradation of EPS is how the EPS is extracted from the matrix or a culture broth. Moreover, EPS matrix available in different forms (crude, loosely bound, tightly bound, slime, capsular and purified) can be used as a bioflocculant material. Several chemical and physical methods for the extraction of EPS (crude form or purified form) from different sources have been analyzed and reported. There is ample information available in the literature about various EPS extraction methods. Flocculability, dewaterability and biosorption ability are the very attractive engineering properties of the EPS matrix. Recent information on important aspects of these properties qualitatively as well as quantitatively has been described. Recent information on the mechanism of flocculation mediated by EPS is presented. Potential role of EPS in sludge dewatering and biosorption phenomenon has been discussed in details. Different factors influencing the EPS ability to flocculate and dewaterability of different suspensions have been included. The factors considered for the discussion are cations, different forms of EPS, concentration of EPS, protein and carbohydrate content of EPS, molecular weight of EPS, pH of the suspension, temperature etc. These factors were selected for the study based upon their role in the flocculation and dewatering mechanism as well the most recent available literature findings on these factors. For example, only recently it has been demonstrated that there is an optimum EPS concentration for sludge flocculation/dewatering. High or low concentration of EPS can lead to destabilization of flocs. Role of EPS in environmental applications such as water treatment, wastewater flocculation and settling, colour removal from wastewater, sludge dewatering, metal removal and recovery, removal of toxic organic compounds, landfill leachate treatment, soil remediation and reclamation has been presented based on the most recent available information. However, data available on environmental application of EPS are very limited. Investigations are required for exploring the potential of field applications of EPS. Finally, the limitations in the knowledge gap are outlined and the research needs as well as future perspectives are highlighted.
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Affiliation(s)
- T T More
- Institut national de la recherche scientifique, Centre Eau, Terre & Environnement, Université du Québec, 490 de la Couronne, Québec, QC G1K 9A9, Canada.
| | - J S S Yadav
- Institut national de la recherche scientifique, Centre Eau, Terre & Environnement, Université du Québec, 490 de la Couronne, Québec, QC G1K 9A9, Canada
| | - S Yan
- Institut national de la recherche scientifique, Centre Eau, Terre & Environnement, Université du Québec, 490 de la Couronne, Québec, QC G1K 9A9, Canada
| | - R D Tyagi
- Institut national de la recherche scientifique, Centre Eau, Terre & Environnement, Université du Québec, 490 de la Couronne, Québec, QC G1K 9A9, Canada.
| | - R Y Surampalli
- U. S. Environmental Protection Agency, P.O. Box 17-2141, Kansas City, KS 66117, USA
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23
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Aljuboori AHR, Uemura Y, Osman NB, Yusup S. Production of a bioflocculant from Aspergillus niger using palm oil mill effluent as carbon source. BIORESOURCE TECHNOLOGY 2014; 171:66-70. [PMID: 25189510 DOI: 10.1016/j.biortech.2014.08.038] [Citation(s) in RCA: 62] [Impact Index Per Article: 6.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/10/2014] [Revised: 08/06/2014] [Accepted: 08/07/2014] [Indexed: 05/22/2023]
Abstract
This study evaluated the potential of bioflocculant production from Aspergillus niger using palm oil mill effluent (POME) as carbon source. The bioflocculant named PM-5 produced by A. niger showed a good flocculating capability and flocculating rate of 76.8% to kaolin suspension could be achieved at 60 h of culture time. Glutamic acid was the most favorable nitrogen source for A. niger in bioflocculant production at pH 6 and temperature 35 °C. The chemical composition of purified PM-5 was mainly carbohydrate and protein with 66.8% and 31.4%, respectively. Results showed the novel bioflocculant (PM-5) had high potential to treat river water from colloids and 63% of turbidity removal with the present of Ca(2+) ion.
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Affiliation(s)
- Ahmad H Rajab Aljuboori
- Centre for Biofuel and Biochemical Research (CBBR), Universiti Teknologi PETRONAS, 31750 Tronoh, Perak, Malaysia.
| | - Yoshimitsu Uemura
- Centre for Biofuel and Biochemical Research (CBBR), Universiti Teknologi PETRONAS, 31750 Tronoh, Perak, Malaysia
| | - Noridah Binti Osman
- Centre for Biofuel and Biochemical Research (CBBR), Universiti Teknologi PETRONAS, 31750 Tronoh, Perak, Malaysia
| | - Suzana Yusup
- Biomass Processing Lab, Universiti Teknologi PETRONAS, 31750 Tronoh, Perak, Malaysia
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Okaiyeto K, Nwodo UU, Mabinya LV, Okoh AI. Evaluation of the flocculation potential and characterization of bioflocculant produced by Micrococcus sp. Leo. APPL BIOCHEM MICRO+ 2014. [DOI: 10.1134/s000368381406012x] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
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Nwodo UU, Okoh AI. Mixed culture fermentation and media optimization by response surface model: Streptomyces and Brachybacterium species in bioflocculant production. Molecules 2014; 19:11131-44. [PMID: 25076145 PMCID: PMC6271801 DOI: 10.3390/molecules190811131] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/09/2014] [Revised: 07/14/2014] [Accepted: 07/21/2014] [Indexed: 12/02/2022] Open
Abstract
The biofloculant production potential of a consortium of Streptomyces and Brachybacterium species were evaluated. Optimum bioflocculant yields (g/L) and flocculation activities (%) were observed for the following preferred nutritional sources: glucose (56%; 2.78 ± 0.15 g/L), (NH4)2NO3 (53%; 2.81 ± 0.37 g/L) and CaSO4·H2O (47%; 2.19 ± 0.13 g/L). A Plackett-Burman design revealed the critical fermentation media components. The concentrations of these components were optimized [glucose; 16.0, (NH4)2NO3; 0.5 and CaSO4·H2O; 1.2 (g/L)] through a central composite design with optimum bioflocculant yield of 3.02 g/L and flocculation activity of 63.7%. The regression coefficient (R2 = 0.6569) indicates a weak estimation of the model’s adequacy and a high lack-of-fit value (34.1%). Lack of synergy in the consortium may have been responsible for the model inadequacy observed. FTIR spectrometry showed the bioflocculant to be a heteropolysaccharide, while SEM imaging revealed an amorphous loosely arranged fluffy structure with interstial spacing of less than 1 µm.
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Affiliation(s)
- Uchechukwu U Nwodo
- Applied and Environmental Microbiology Research Group (AEMREG), Department of Biochemistry and Microbiology, University of Fort Hare, Private Bag X1314, Alice 5700, South Africa.
| | - Anthony I Okoh
- Applied and Environmental Microbiology Research Group (AEMREG), Department of Biochemistry and Microbiology, University of Fort Hare, Private Bag X1314, Alice 5700, South Africa.
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Bioflocculant production by a consortium of Streptomyces and Cellulomonas species and media optimization via surface response model. Colloids Surf B Biointerfaces 2014; 116:257-64. [DOI: 10.1016/j.colsurfb.2014.01.008] [Citation(s) in RCA: 50] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/19/2013] [Revised: 12/20/2013] [Accepted: 01/06/2014] [Indexed: 11/18/2022]
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Nwodo UU, Agunbiade MO, Green E, Nwamadi M, Rumbold K, Okoh AI. Characterization of an Exopolymeric Flocculant Produced by a Brachybacterium sp. MATERIALS 2013; 6:1237-1254. [PMID: 28809207 PMCID: PMC5452324 DOI: 10.3390/ma6041237] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 02/02/2013] [Revised: 03/03/2013] [Accepted: 03/05/2013] [Indexed: 11/16/2022]
Abstract
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.
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Affiliation(s)
- Uchechukwu U Nwodo
- Applied and Environmental Microbiology Research Group (AEMREG), Department of Biochemistry and Microbiology, University of Fort Hare, Private Bag X1314, Alice 5700, South Africa.
| | - Mayowa O Agunbiade
- Applied and Environmental Microbiology Research Group (AEMREG), Department of Biochemistry and Microbiology, University of Fort Hare, Private Bag X1314, Alice 5700, South Africa.
| | - Ezekiel Green
- Applied and Environmental Microbiology Research Group (AEMREG), Department of Biochemistry and Microbiology, University of Fort Hare, Private Bag X1314, Alice 5700, South Africa.
| | - Mutshinyalo Nwamadi
- Spectra Analytical Facility, University of Johannesburg, Auckland Park 2006, South Africa.
| | - Karl Rumbold
- School of Molecular and Cell Biology, University of the Witwatersrand, Johannesburg, Gauteng, ZA 2050, South Africa.
| | - Anthony I Okoh
- Applied and Environmental Microbiology Research Group (AEMREG), Department of Biochemistry and Microbiology, University of Fort Hare, Private Bag X1314, Alice 5700, South Africa.
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Nwodo U, Okoh A. Characterization and flocculation properties of biopolymeric flocculant (glycosaminoglycan) produced by Cellulomonas
sp. Okoh. J Appl Microbiol 2013; 114:1325-37. [DOI: 10.1111/jam.12095] [Citation(s) in RCA: 38] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/18/2012] [Revised: 11/27/2012] [Accepted: 11/28/2012] [Indexed: 11/26/2022]
Affiliation(s)
- U.U. Nwodo
- Department of Biochemistry and Microbiology; Applied and Environmental Microbiology Research Group (AEMREG), University of Fort Hare; Alice South Africa
| | - A.I. Okoh
- Department of Biochemistry and Microbiology; Applied and Environmental Microbiology Research Group (AEMREG), University of Fort Hare; Alice South Africa
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Nwodo UU, Green E, Okoh AI. Bacterial exopolysaccharides: functionality and prospects. Int J Mol Sci 2012; 13:14002-15. [PMID: 23203046 PMCID: PMC3509562 DOI: 10.3390/ijms131114002] [Citation(s) in RCA: 329] [Impact Index Per Article: 27.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/07/2012] [Revised: 10/05/2012] [Accepted: 10/24/2012] [Indexed: 12/27/2022] Open
Abstract
Diverse structural, functional and valuable polysaccharides are synthesized by bacteria of all taxa and secreted into the external environment. These polysaccharides are referred to as exopolysaccharides and they may either be homopolymeric or heteropolymeric in composition and of diverse high molecular weights (10 to 1000 kDa). The material properties of exopolysaccharides have revolutionized the industrial and medical sectors due to their retinue of functional applications and prospects. These applications have been extensive in areas such as pharmacological, nutraceutical, functional food, cosmeceutical, herbicides and insecticides among others, while prospects includes uses as anticoagulant, antithrombotic, immunomodulation, anticancer and as bioflocculants. Due to the extensive applications of bacterial exopolysaccharides, this overview provides basic information on their physiologic and morphologic functions as well as their applications and prospects in the medical and industrial sectors.
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Affiliation(s)
- Uchechukwu U. Nwodo
- Applied and Environmental Microbiology Research Group (AEMREG), Department of Biochemistry and Microbiology, University of Fort Hare, Private Bag X1314, Alice 5700, South Africa; E-Mails: (E.G.); (A.I.O.)
| | - Ezekiel Green
- Applied and Environmental Microbiology Research Group (AEMREG), Department of Biochemistry and Microbiology, University of Fort Hare, Private Bag X1314, Alice 5700, South Africa; E-Mails: (E.G.); (A.I.O.)
| | - Anthony I. Okoh
- Applied and Environmental Microbiology Research Group (AEMREG), Department of Biochemistry and Microbiology, University of Fort Hare, Private Bag X1314, Alice 5700, South Africa; E-Mails: (E.G.); (A.I.O.)
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A freshwater streptomyces, isolated from Tyume River, produces a predominantly extracellular glycoprotein bioflocculant. Int J Mol Sci 2012; 13:8679-8695. [PMID: 22942728 PMCID: PMC3430259 DOI: 10.3390/ijms13078679] [Citation(s) in RCA: 34] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/15/2012] [Revised: 06/18/2012] [Accepted: 06/21/2012] [Indexed: 11/25/2022] Open
Abstract
We evaluated bioflocculant production by a freshwater actinobacteria whose 16S rDNA nucleotide sequence was deposited in GenBank as Streptomyces sp. Gansen (accession number HQ537129). Optimum culture conditions for bioflocculant production were an initial medium pH of 6.8, incubation temperature of 30 °C, agitation speed of 160 rpm and an inoculum size of 2% (v/v) of cell density 1.5 × 108 cfu/mL. The carbon, nitrogen and cation sources for optimum bioflocculant production were glucose (89% flocculating activity), ammonium sulfate (76% flocculating activity) and MgCl2. Bioflocculant pyrolysis showed three step decomposition indicative of three components while chemical analyses showed 78% carbohydrate and 22% protein (wt/wt). The mass ratio of neutral sugar, amino sugar and uronic acids was 4.6:2.4:3. FTIR spectrometry indicated the presence of carboxyl, hydroxyl and amino groups, typical for heteropolysaccharide. The bioflocculant showed a lattice structure as seen by SEM imaging. Its high flocculation activity suggests its suitability for industrial applicability.
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