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Zhou Y, Cui X, Wu B, Wang Z, Liu Y, Ren T, Xia S, Rittmann BE. Microalgal extracellular polymeric substances (EPS) and their roles in cultivation, biomass harvesting, and bioproducts extraction. BIORESOURCE TECHNOLOGY 2024; 406:131054. [PMID: 38944317 DOI: 10.1016/j.biortech.2024.131054] [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: 05/14/2024] [Revised: 06/25/2024] [Accepted: 06/26/2024] [Indexed: 07/01/2024]
Abstract
Microalgae extracellular polymeric substances (EPS) are complex high-molecular-weight polymers and the physicochemical properties of EPS strongly affect the core features of microalgae cultivation and resource utilization. Revealing the key roles of EPS in microalgae life-cycle processes in an interesting and novelty topic to achieve energy-efficient practical application of microalgae. This review found that EPS showed positive effect in non-gas uptake, extracellular electron transfer, toxicity resistance and heterotrophic symbiosis, but negative impact in gas transfer and light utilization during microalgae cultivation. For biomass harvesting, EPS favored biomass flocculation and large-size cell self-flocculation, but unfavored small size microalgae self-flocculation, membrane filtration, charge neutralization and biomass dewatering. During bioproducts extraction, EPS exhibited positive impact in extractant uptake, but the opposite effect in cellular membrane permeability and cell rupture. Future research on microalgal EPS were also identified, which offer suggestions for comprehensive understanding of microalgal EPS roles in various scenarios.
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Affiliation(s)
- Yun Zhou
- College of Resources and Environment, Huazhong Agricultural University, Wuhan 430070, China.
| | - Xiaocai Cui
- College of Resources and Environment, Huazhong Agricultural University, Wuhan 430070, China
| | - Beibei Wu
- College of Resources and Environment, Huazhong Agricultural University, Wuhan 430070, China
| | - Ziqi Wang
- College of Resources and Environment, Huazhong Agricultural University, Wuhan 430070, China
| | - Ying Liu
- College of Resources and Environment, Huazhong Agricultural University, Wuhan 430070, China
| | - Tian Ren
- College of Resources and Environment, Huazhong Agricultural University, Wuhan 430070, China
| | - Siqing Xia
- State Key Laboratory of Pollution Control and Resource Reuse, College of Environmental Science and Engineering, Tongji University, Shanghai 200092, China
| | - Bruce E Rittmann
- Biodesign Swette Center for Environmental Biotechnology, Arizona State University, Tempe, AZ 85287-5701, United States of America
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Liu MY, Liu XY, Guo YY, Ma JY, Duan JL, Zhang M, Han Y, Sun XD, Sun YC, Wang Y, Yuan XZ, Feng LJ. Nitrogen Forms Regulate the Response of Microcystis aeruginosa to Nanoplastics at Environmentally Relevant Nitrogen Concentrations. ACS NANO 2024; 18:11828-11836. [PMID: 38659192 DOI: 10.1021/acsnano.4c00739] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 04/26/2024]
Abstract
As essential primary producers, cyanobacteria play a major role in global carbon and nitrogen cycles. Though the influence of nanoplastics on the carbon metabolism of cyanobacteria is well-studied, little is known about how nanoplastics affect their nitrogen metabolism, especially under environmentally relevant nitrogen concentrations. Here, we show that nitrogen forms regulated growth inhibition, nitrogen consumption, and the synthesis and release of microcystin (MC) in Microcystis aeruginosa exposed to 10 μg/mL amino-modified polystyrene nanoplastics (PS-NH2) with a particle size of 50 nm under environmentally relevant nitrogen concentrations of nitrate, ammonium, and urea. We demonstrate that PS-NH2 inhibit M. aeruginosa differently in nitrate, urea, and ammonium, with inhibition rates of 51.87, 39.70, and 36.69%, respectively. It is caused through the differences in impairing cell membrane integrity, disrupting redox homeostasis, and varying nitrogen transport pathways under different nitrogen forms. M. aeruginosa respond to exposure of PS-NH2 by utilizing additional nitrogen to boost the production of amino acids, thereby enhancing the synthesis of MC, extracellular polymeric substances, and membrane phospholipids. Our results found that the threat of nanoplastics on primary producers can be regulated by the nitrogen forms in freshwater ecosystems, contributing to a better understanding of nanoplastic risks under environmentally relevant conditions.
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Affiliation(s)
- Mei-Yan Liu
- Shandong Key Laboratory of Environmental Processes and Health, School of Environmental Science and Engineering, Shandong University, Qingdao, Shandong 266237, P. R. China
| | - Xiao-Yu Liu
- Shandong Key Laboratory of Environmental Processes and Health, School of Environmental Science and Engineering, Shandong University, Qingdao, Shandong 266237, P. R. China
| | - Yu-Yu Guo
- State Key Laboratory of Microbial Technology, Shandong University, Qingdao 266237, P. R. China
| | - Jing-Ya Ma
- Shandong Key Laboratory of Environmental Processes and Health, School of Environmental Science and Engineering, Shandong University, Qingdao, Shandong 266237, P. R. China
| | - Jian-Lu Duan
- Shandong Key Laboratory of Environmental Processes and Health, School of Environmental Science and Engineering, Shandong University, Qingdao, Shandong 266237, P. R. China
| | - Mou Zhang
- Shandong Key Laboratory of Environmental Processes and Health, School of Environmental Science and Engineering, Shandong University, Qingdao, Shandong 266237, P. R. China
| | - Yi Han
- Shandong Key Laboratory of Environmental Processes and Health, School of Environmental Science and Engineering, Shandong University, Qingdao, Shandong 266237, P. R. China
| | - Xiao-Dong Sun
- Shandong Key Laboratory of Environmental Processes and Health, School of Environmental Science and Engineering, Shandong University, Qingdao, Shandong 266237, P. R. China
| | - Yu-Chen Sun
- Shandong Key Laboratory of Environmental Processes and Health, School of Environmental Science and Engineering, Shandong University, Qingdao, Shandong 266237, P. R. China
| | - Yue Wang
- Shandong Key Laboratory of Environmental Processes and Health, School of Environmental Science and Engineering, Shandong University, Qingdao, Shandong 266237, P. R. China
| | - Xian-Zheng Yuan
- Shandong Key Laboratory of Environmental Processes and Health, School of Environmental Science and Engineering, Shandong University, Qingdao, Shandong 266237, P. R. China
- Sino-French Research Institute for Ecology and Environment (ISFREE), Shandong University, Qingdao, Shandong 266237, P. R. China
| | - Li-Juan Feng
- Shandong Key Laboratory of Environmental Processes and Health, School of Environmental Science and Engineering, Shandong University, Qingdao, Shandong 266237, P. R. China
- College of Geography and Environment, Shandong Normal University, Jinan, Shandong 250014, P. R. China
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Reignier O, Bormans M, Marchand L, Sinquin C, Amzil Z, Zykwinska A, Briand E. Production and composition of extracellular polymeric substances by a unicellular strain and natural colonies of Microcystis: Impact of salinity and nutrient stress. ENVIRONMENTAL MICROBIOLOGY REPORTS 2023; 15:783-796. [PMID: 37697704 PMCID: PMC10667651 DOI: 10.1111/1758-2229.13200] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/14/2023] [Accepted: 08/22/2023] [Indexed: 09/13/2023]
Abstract
The transfer of toxic cyanobacterial Microcystis blooms from freshwater to estuaries constitutes a serious environmental problem worldwide that is expected to expand in scale and intensity with anthropogenic and climate change. The formation and maintenance of Microcystis in colonial form is conditioned to the presence of extracellular polymeric substances (EPS). In this study, we attempted to better understand how the mucilaginous colonial form of Microcystis evolves under environmental stress conditions. In particular, we studied and compared the production and the composition of EPS fractions (attached and free) from natural colonies of a Microcystis bloom and from a unicellular M. aeruginosa strain under salinity and nutrient stress (representing a land-sea continuum). Our results highlighted a greater production of EPS from the natural colonies of Microcystis than the unicellular one under nutrient and combined stress conditions dominated by the attached form. In comparison to the unicellular Microcystis, EPS produced by the colonial form were characterized by high molecular weight polysaccharides which were enriched in uronic acids and hexosamines, notably for the free fraction in response to increased salinities. This complex extracellular matrix gives the cells the ability to aggregate and allows the colonial cyanobacterial population to cope with osmotic shock.
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Ren Y, Jia Z, Liu Y, Liang C, Zhang X, Xu D, Ye N. Elevated pCO 2 alleviates the toxic effects of polystyrene nanoparticles on the marine microalga Nannochloropsis oceanica. THE SCIENCE OF THE TOTAL ENVIRONMENT 2023; 895:164985. [PMID: 37364831 DOI: 10.1016/j.scitotenv.2023.164985] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/10/2023] [Revised: 06/02/2023] [Accepted: 06/16/2023] [Indexed: 06/28/2023]
Abstract
Concerns about the environmental effects of nanoplastics on marine ecosystems are increasing. Ocean acidification (OA) has also become a global environmental problem. Plastic pollution occurs concomitantly with anthropogenic climate stressors such as OA. However, the combined effects of NP and OA on marine phytoplankton are still not well understood. Therefore, we have investigated the behavior of ammonia (NH2) polystyrene nanoparticles (PS NP) in f/2 medium under 1000 μatm pCO2 and discussed the toxicity of PS NP (100 nm; 0.5 and 1.5 mg/L) on Nannochloropsis oceanica under long and short-term acidification (LA and SA; pCO2 ~ 1000 μatm). We observed PS NP suspended in pCO2 1000 μatm f/2 medium aggregated to a size greater than nanoscale (1339.00 ± 76.10 nm). In addition, we found that PS NP significantly inhibited the growth of N. oceanica at two concentrations, which also produced oxidative stress. Whereas, the growth of algal cells under the coupling of acidification and PS NP was significantly better than that of single PS NP exposure. This indicated that acidification significantly alleviated the toxic effects of PS NP on N. oceanica, and long-term acidification can even promote the growth of N. oceanica under low-density NP. To further understand the mechanism, we analyzed a comparative transcriptome. The results showed that PS NP exposure inhibited the expression of genes involved in the TCA cycle. The acidification was possibly reflected in ribosomes and corresponding processes, which alleviated the negative effects of PS NP on N. oceanica by promoting the synthesis of related enzymes and proteins. This study provided a theoretical basis for assessing the damage of NP to marine phytoplankton under OA. We propose that future studies evaluating the toxicology of NP to marine ecology should consider the changing ocean climate.
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Affiliation(s)
- Yudong Ren
- College of Marine Science and Biological Engineering, Qingdao University of Science and Technology, Qingdao, China
| | - Zhihua Jia
- College of Marine Science and Biological Engineering, Qingdao University of Science and Technology, Qingdao, China
| | - Yajing Liu
- College of Marine Science and Biological Engineering, Qingdao University of Science and Technology, Qingdao, China
| | - Chengwei Liang
- College of Marine Science and Biological Engineering, Qingdao University of Science and Technology, Qingdao, China.
| | - Xiaowen Zhang
- Yellow Sea Fisheries Research Institute, Chinese Academy of Fishery Sciences, Qingdao, China; Function Laboratory for Marine Fisheries Science and Food Production Processes, Qingdao National Laboratory for Marine Science and Technology, Qingdao, China
| | - Dong Xu
- Yellow Sea Fisheries Research Institute, Chinese Academy of Fishery Sciences, Qingdao, China; Function Laboratory for Marine Fisheries Science and Food Production Processes, Qingdao National Laboratory for Marine Science and Technology, Qingdao, China
| | - Naihao Ye
- Yellow Sea Fisheries Research Institute, Chinese Academy of Fishery Sciences, Qingdao, China; Function Laboratory for Marine Fisheries Science and Food Production Processes, Qingdao National Laboratory for Marine Science and Technology, Qingdao, China.
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Han J, Li H, Liu Y, Liu P, Song Y, Wang Y, Zhang L, Wang W. Extraction of extracellular polymeric substances (EPS) from indigenous bacteria of rare earth tailings and application to removal of thorium ions (Th 4+). WATER SCIENCE AND TECHNOLOGY : A JOURNAL OF THE INTERNATIONAL ASSOCIATION ON WATER POLLUTION RESEARCH 2023; 87:83-98. [PMID: 36640025 DOI: 10.2166/wst.2022.411] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/17/2023]
Abstract
Thorium, as an important radioactive element, is widely present in nature, and its accompanying environmental pollution is also serious. Extracellular polymeric substances (EPS) are commonly found on the surface of microbial bodies and have strong adsorption capacity for metal ions. In this study, four methods were used to extract EPS from indigenous bacteria of rare earth tailings and to determine the best extraction method. The extracted EPS was applied to treat Th4+, and the changes in functional groups and composition of EPS were investigated. The results showed that the ultrasonic method was more efficient than other methods. The best removal efficiency was observed at pH 3.5, Th4+ concentration of 20 mg/L, and EPS dosage of 30 mL at 25 °C. After 9 h, the adsorption process reached equilibrium with a maximum removal efficiency of 75.93% and a maximum theoretical adsorption capacity of 25.96 mg/g. The Th4+ removal process was consistent with the Langmuir and Freundlich adsorption isotherms and the kinetic data were consistent with the pseudo-second-order kinetic model, which is mainly based on chemisorption. Amide I and amide II of proteins, C-H from aliphatic, as well as O-H and C = O from carboxylic acid play important roles in the adsorption process.
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Affiliation(s)
- Jianhong Han
- School of Energy and Environment, Inner Mongolia University of Science and Technology, No.7, Alding street, Baotou, Inner Mongolia 014010, China E-mail:
| | - Hongyan Li
- School of Energy and Environment, Inner Mongolia University of Science and Technology, No.7, Alding street, Baotou, Inner Mongolia 014010, China E-mail:
| | - Yi Liu
- School of Chemical Engineering and Technology, TianGong University, No. 399, Binshui West Road, Xiqing District, Tianjin 300130, China
| | - Pai Liu
- School of Chemical Engineering and Technology, TianGong University, No. 399, Binshui West Road, Xiqing District, Tianjin 300130, China
| | - Yi Song
- School of Energy and Environment, Inner Mongolia University of Science and Technology, No.7, Alding street, Baotou, Inner Mongolia 014010, China E-mail:
| | - Yuting Wang
- School of Energy and Environment, Inner Mongolia University of Science and Technology, No.7, Alding street, Baotou, Inner Mongolia 014010, China E-mail:
| | - Lianke Zhang
- School of Energy and Environment, Inner Mongolia University of Science and Technology, No.7, Alding street, Baotou, Inner Mongolia 014010, China E-mail:
| | - Weida Wang
- School of Energy and Environment, Inner Mongolia University of Science and Technology, No.7, Alding street, Baotou, Inner Mongolia 014010, China E-mail:
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Sun A, Xu L, Zhou G, Yin E, Chen T, Wang Y, Li X. Roles of polystyrene micro/nano-plastics as carriers on the toxicity of Pb 2+ to Chlamydomonas reinhardtii. CHEMOSPHERE 2022; 309:136676. [PMID: 36191764 DOI: 10.1016/j.chemosphere.2022.136676] [Citation(s) in RCA: 10] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/08/2022] [Revised: 09/27/2022] [Accepted: 09/28/2022] [Indexed: 06/16/2023]
Abstract
Little information could be consulted on the impacts of micro-plastics as carriers on toxicity of heavy metals, especially for micro-plastics of different sizes. Therefore, this study investigated the adsorption and desorption of Pb2+ on polystyrene plastics with nano- and micro-size (NPs and MPs), and further evaluated the roles of NPs and MPs as carriers on the toxicity of Pb2+ to Chlamydomonas reinhardtii (C. reinhardtii). The results showed that NPs showed higher adsorption capacities and a lower desorption rate for Pb2+ than MPs. The growth inhibitory rates (IR) of mixed and loaded Pb2+ with MPs to C. reinhardtii were 18.29% and 15.76%, respectively, which were lower than that of Pb2+ (22.28%). The presence of MPs decreased the bioavailability of Pb2+ to C. reinhardtii by a competitive adsorption for Pb2+ between MPs and algal cells, and suppressed membrane damage and oxidative stress caused by Pb2+. Maximum IR was observed for the mixture of NPs with Pb2+ (35.64%), followed by Pb2+ loaded on NPs (30.13%), single NPs (26.71%) and Pb2+ (21.01%). The internalization of NPs with absorbed Pb2+ intensified lipid peroxidation. The mixed and loaded microplastics with Pb2+ had more negative effects on C. reinhardtii than the single microplastics. The size-dependent effect was observed in the capacity of heavy metal ions carried by microplastics and the roles of microplastics as carriers on the toxicity of Pb2+. The results showed that the indirect risk of microplastics as 'carriers' could not be ignored, especially for NPs.
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Affiliation(s)
- Aoxue Sun
- College of Water Conservancy and Civil Engineering, Shandong Agricultural University, Tai'an, Shandong, 271018, China
| | - Limei Xu
- College of Water Conservancy and Civil Engineering, Shandong Agricultural University, Tai'an, Shandong, 271018, China; State Key Laboratory of Crop Biology, College of Life Sciences, Shandong Agricultural University, Tai'an, Shandong, 271018, China
| | - Gaoxiang Zhou
- College of Water Conservancy and Civil Engineering, Shandong Agricultural University, Tai'an, Shandong, 271018, China
| | - Erqin Yin
- College of Water Conservancy and Civil Engineering, Shandong Agricultural University, Tai'an, Shandong, 271018, China
| | - Tiantian Chen
- College of Water Conservancy and Civil Engineering, Shandong Agricultural University, Tai'an, Shandong, 271018, China
| | - Yong Wang
- State Key Laboratory of Crop Biology, College of Life Sciences, Shandong Agricultural University, Tai'an, Shandong, 271018, China.
| | - Xiaochen Li
- College of Water Conservancy and Civil Engineering, Shandong Agricultural University, Tai'an, Shandong, 271018, China.
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Abstract
Microalgae are used in flocculation processes because biopolymers are released into the culture medium. Microalgal cell growth under specific conditions (temperature, pH, luminosity, nutrients, and salinity) provides the production and release of exopolysaccharides (EPS). These biopolymers can be recovered from the medium for application as bioflocculants or used directly in cultivation as microalgae autoflocculants. The optimization of nutritional parameters, the control of process conditions, and the possibility of scaling up allow the production and industrial application of microalgal EPS. Therefore, this review addresses the potential use of EPS produced by microalgae in bioflocculation. The recovery, determination, and quantification techniques for these biopolymers are also addressed. Moreover, other technological applications of EPS are highlighted.
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Xu L, Zhao Z, Yan Z, Zhou G, Zhang W, Wang Y, Li X. Defense pathways of Chlamydomonas reinhardtii under silver nanoparticle stress: Extracellular biosorption, internalization and antioxidant genes. CHEMOSPHERE 2022; 291:132764. [PMID: 34752836 DOI: 10.1016/j.chemosphere.2021.132764] [Citation(s) in RCA: 10] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/23/2021] [Revised: 10/25/2021] [Accepted: 10/31/2021] [Indexed: 06/13/2023]
Abstract
Numerous studies have been investigated the toxic effects of silver nanoparticle (Ag-NPs) on algae; however, little attention has been paid to the defense pathways of algae cells to Ag-NPs. In the study, Chlamydomonas reinhardtii (C. reinhardtii) was selected as a model organism to investigate the defense mechanisms to Ag-NPs exposure. The results showed that exopolysaccharide and protein in bound-extracellular polymeric substances significantly increased under Ag-NPs stress. These metal-binding groups including C-O-C (exopolysaccharide), CH3/CH2 (proteins), O-H/N-H (hydroxyl group) and C-H (alkyl groups) played a key role in extracellular biosorption. The internalized or strongly bound Ag (1.90%-17.45% of total contents) was higher than the loosely surface biosorption (0.31%-1.79%). The accumulation of glutathione disulfide (GSSG), together with the decline of reduced glutathione/GSSG (GSH/GSSG) ratio in C. reinhardtii cells, indicated a significant oxidative stress caused by exposure of Ag-NPs. The increasing phytochelatin accompanied with the decreasing GSH level indicated a critical role to intracellular detoxification of Ag. Furthermore, upregulation of antioxidant genes (MSOD, QTOX2, CAT1, GPX2, APX and VTE3) can cope with oxidative stress of Ag-NPs or Ag+. The up-regulation of ascorbate peroxidase (APX) and glutathione peroxidase (GPX2) genes and the reduction in GSH contents showed that the toxicity of Ag-NPs could be mediated by an intracellular ascorbate-GSH defense pathway. These findings can provide valuable information on ecotoxicity of Ag-NPs, potential bioremediation and adaptation capabilities of algal cells to Ag-NPs.
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Affiliation(s)
- Limei Xu
- State Key Laboratory of Crop Biology, College of Life Sciences, Shandong Agricultural University, Tai'an, Shandong, 271018, China; College of Water Conservancy and Civil Engineering, Shandong Agricultural University, Tai'an, Shandong, 271018, China
| | - Zhilin Zhao
- College of Water Conservancy and Civil Engineering, Shandong Agricultural University, Tai'an, Shandong, 271018, China
| | - Zhen Yan
- College of Water Conservancy and Civil Engineering, Shandong Agricultural University, Tai'an, Shandong, 271018, China
| | - Gaoxiang Zhou
- College of Water Conservancy and Civil Engineering, Shandong Agricultural University, Tai'an, Shandong, 271018, China
| | - Wenming Zhang
- Department of Civil and Environmental Engineering, University of Alberta, Edmonton, Alberta, T6G 1H9, Canada
| | - Yong Wang
- State Key Laboratory of Crop Biology, College of Life Sciences, Shandong Agricultural University, Tai'an, Shandong, 271018, China.
| | - Xiaochen Li
- College of Water Conservancy and Civil Engineering, Shandong Agricultural University, Tai'an, Shandong, 271018, China.
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Extraction of the Bacterial Extracellular Polysaccharide FucoPol by Membrane-Based Methods: Efficiency and Impact on Biopolymer Properties. Polymers (Basel) 2022; 14:polym14030390. [PMID: 35160380 PMCID: PMC8838009 DOI: 10.3390/polym14030390] [Citation(s) in RCA: 9] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/15/2021] [Revised: 01/08/2022] [Accepted: 01/17/2022] [Indexed: 02/06/2023] Open
Abstract
In this study, membrane-based methods were evaluated for the recovery of FucoPol, the fucose-rich exopolysaccharide (EPS) secreted by the bacterium Enterobacter A47, aiming at reducing the total water consumption and extraction time, while keeping a high product recovery, thus making the downstream procedure more sustainable and cost-effective. The optimized method involved ultrafiltration of the cell-free supernatant using a 30 kDa molecular weight cut-off (MWCO) membrane that allowed for a 37% reduction of the total water consumption and a 55% reduction of the extraction time, compared to the previously used method (diafiltration-ultrafiltration with a 100 kDa MWCO membrane). This change in the downstream procedure improved the product’s recovery (around 10% increase) and its purity, evidenced by the lower protein (8.2 wt%) and inorganic salts (4.0 wt%) contents of the samples (compared to 9.3 and 8.6 wt%, respectively, for the previously used method), without impacting FucoPol’s sugar and acyl groups composition, molecular mass distribution or thermal degradation profile. The biopolymer’s emulsion-forming and stabilizing capacity was also not affected (emulsification activity (EA) with olive oil, at a 2:3 ratio, of 98 ± 0% for all samples), while the rheological properties were improved (the zero-shear viscosity increased from 8.89 ± 0.62 Pa·s to 17.40 ± 0.04 Pa·s), which can be assigned to the higher purity degree of the extracted samples. These findings demonstrate a significant improvement in the downstream procedure raising FucoPol’s recovery, while reducing water consumption and operation time, key criteria in terms of process economic and environmental sustainability. Moreover, those changes improved the biopolymer’s rheological properties, known to significantly impact FucoPol’s utilization in cosmetic, pharmaceutical or food products.
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