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Cai G, Yu X, Cai R, Wang H. Eliminating the ecological hazards of Heterosigma akashiwo bloom by a microbial algicide: removal of nitrite contamination, redirection of carbon flow and restoration of metabolic generalists. FEMS Microbiol Ecol 2022; 99:6955817. [PMID: 36546573 DOI: 10.1093/femsec/fiac154] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/08/2022] [Revised: 12/13/2022] [Accepted: 12/17/2022] [Indexed: 12/24/2022] Open
Abstract
Harmful algal blooms (HABs) attracted much attention due to their extensive ecological hazards and the increasing influences on global biogeochemical cycles with the intensification of human impact and global warming. Lysing algal cells with species-specific microbial algicide seemed to be promising to eliminate HABs, but the potential ecotoxicity was rarely studied. In this study, microcosms simulating Heterosigma akashiwo blooms were established to reveal the influences of a microbial algicide from Streptomyces sp. U3 on the biological, physicochemical parameters and bacterial community. The results showed that H. akashiwo bloom accumulated nitrite to a lethal dose, produced bio-labile DOM with widespread influences and enriched pathogenic Coxiella to a high abundance. Lysing H. akashiwo cells by microbial algicide induced a bacterial bloom, eliminated nitrite contamination, enhanced the recalcitrance of DOM, and restored bacterial population from a Gammaproteobacteria-dominant community during bloom back to an Alphaproteobacteria-dominant community similar to the non-bloom seawater. Succession of bacterial genera further suggested that the variation from algal exudates to lysates promoted the restoration of metabolic generalists, which redirected the carbon flow to a less ecologically impactive path. This study revealed the benefits of using microbial algicide to remediate the ecological hazards of HABs, which provided references for future application.
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Affiliation(s)
- Guanjing Cai
- Biology Department and Institute of Marine Sciences, College of Science, and Guangdong Provincial Key Laboratory of Marine Biotechnology, Shantou University, Shantou 515063, China.,State Key Laboratory of Marine Environmental Science and Key Laboratory of the Ministry of Education for Coastal and Wetland Ecosystems, School of Life Sciences, Xiamen University, Xiamen 361005, China
| | - Xiaoqi Yu
- State Key Laboratory of Marine Environmental Science and Key Laboratory of the Ministry of Education for Coastal and Wetland Ecosystems, School of Life Sciences, Xiamen University, Xiamen 361005, China
| | - Runlin Cai
- Biology Department and Institute of Marine Sciences, College of Science, and Guangdong Provincial Key Laboratory of Marine Biotechnology, Shantou University, Shantou 515063, China
| | - Hui Wang
- Biology Department and Institute of Marine Sciences, College of Science, and Guangdong Provincial Key Laboratory of Marine Biotechnology, Shantou University, Shantou 515063, China
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Yue Y, Chen C, Zhong K, Wu Y, Gao H. Purification, Fermentation Optimization, and Antibacterial Activity of Pyrrole-2-carboxylic Acid Produced by an Endophytic Bacterium, Bacillus cereus ZBE, Isolated from Zanthoxylum bungeanum. Ind Eng Chem Res 2022. [DOI: 10.1021/acs.iecr.1c04164] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Affiliation(s)
- Yuxi Yue
- College of Biomass Science and Engineering and Healthy Food Evaluation Research Center, Sichuan University, Chengdu 610065, P. R. China
| | - Chong Chen
- Key Laboratory of Tropical Crop Products Processing of Ministry of Agriculture and Rural Affairs, Agricultural Products Processing Research Institute, Chinese Academy of Tropical Agricultural Sciences, Zhanjiang, Guangdong 524001, P. R. China
| | - Kai Zhong
- College of Biomass Science and Engineering and Healthy Food Evaluation Research Center, Sichuan University, Chengdu 610065, P. R. China
| | - Yanping Wu
- College of Biomass Science and Engineering and Healthy Food Evaluation Research Center, Sichuan University, Chengdu 610065, P. R. China
| | - Hong Gao
- College of Biomass Science and Engineering and Healthy Food Evaluation Research Center, Sichuan University, Chengdu 610065, P. R. China
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Sales de Menezes LH, Carneiro LL, Maria de Carvalho Tavares I, Santos PH, Pereira das Chagas T, Mendes AA, Paranhos da Silva EG, Franco M, Rangel de Oliveira J. Artificial neural network hybridized with a genetic algorithm for optimization of lipase production from Penicillium roqueforti ATCC 10110 in solid-state fermentation. BIOCATALYSIS AND AGRICULTURAL BIOTECHNOLOGY 2021. [DOI: 10.1016/j.bcab.2020.101885] [Citation(s) in RCA: 12] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/05/2023]
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Liu K, Jiang B, Wang Q, Yang L, Lu B, Li X, Yuan H. Study on the Conditions of Pretreating Vinegar Residue with Sodium Hydroxide for Simultaneous Saccharification and Fermentation to Produce Alcohol and Xylose. FOOD SCIENCE AND TECHNOLOGY RESEARCH 2020. [DOI: 10.3136/fstr.26.381] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/03/2022]
Affiliation(s)
- Kunyi Liu
- College of Wuliangye Technology and Food Engineering, Yibin Vocational and Technical College
- College of Food Science and Technology/College of Longrun Pu-erh Tea, Yunnan Agricultural University
| | - Bin Jiang
- College of Food Science and Technology/College of Longrun Pu-erh Tea, Yunnan Agricultural University
| | - Qi Wang
- College of Wuliangye Technology and Food Engineering, Yibin Vocational and Technical College
| | - Liran Yang
- College of Food Science and Technology/College of Longrun Pu-erh Tea, Yunnan Agricultural University
| | - Bing Lu
- College of Wuliangye Technology and Food Engineering, Yibin Vocational and Technical College
| | - Xiuping Li
- College of Wuliangye Technology and Food Engineering, Yibin Vocational and Technical College
| | - Huawei Yuan
- College of Life Science and Food Engineering/Solid-state Fermentation Resource Utilization Key Laboratory of Sichuan Province, Yibin University
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Engineering diverse eubacteria promoters for robust Gene expression in Streptomyces lividans. J Biotechnol 2018; 289:93-102. [PMID: 30481545 DOI: 10.1016/j.jbiotec.2018.11.017] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/21/2018] [Revised: 11/13/2018] [Accepted: 11/20/2018] [Indexed: 11/23/2022]
Abstract
Due to the lack of powerful gene regulation elements, the engineering development of Streptomyces is often limited. Here, we disclosed that the heterologous σ70 -dependent promoters, which have been reported as inefficient tools for gene expression in Streptomyces, could be efficiently recognized by Streptomyces housekeeping factor σhrdB. Therefore, an effective strategy was developed to engineer these promoters for robust gene expression in Streptomyces by fusing them with optimized 5'-untranslation regions (5'-UTRs). As a proof of concept, the widely used Ptac in E. coli was engineered by fusing its core promoter region with the 5'-UTRR15 from a relatively powerful Streptomyces promoter PkasO*R15 and resulted in Ptac*, the activity of which was 8.1-fold that of Ptac and 1.7-fold that of PkasO*R15 in S. lividans TK24. Next, the 5'-UTRR15 was optimized by randomizing the ribosome binding site (RBS). Based on the base biases of those RBSs with higher activity, eight artificial RBSs were rationally designed, and the optimal resulting promoter Ptac*RBS3 showed about 2.1, 3.6, and 17.6 times the activity of Ptac*, PkasO*R15, and Ptac, respectively, demonstrating that the heterologous Ptac was converted into a type of robust Streptomyces promoters. This study thus greatly expands promoter diversity for the engineering of Streptomyces.
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Kuo YM, Yang J, Liu WW, Zhao E, Li R, Yao L. Using generalized additive models to investigate factors influencing cyanobacterial abundance through phycocyanin fluorescence in East Lake, China. ENVIRONMENTAL MONITORING AND ASSESSMENT 2018; 190:599. [PMID: 30238229 DOI: 10.1007/s10661-018-6981-z] [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: 06/11/2018] [Accepted: 09/13/2018] [Indexed: 06/08/2023]
Abstract
East Lake is a shallow lake (in Wuhan, China) where cyanobacteria blooms occurred frequently from 1970 to 1985. During the study period, all Carlson trophic state index values were > 50, indicating that East Lake is in a eutrophic state. In this study, phycocyanin concentrations were measured through phycocyanin fluorometry for rapid assessment of cyanobacterial abundance. The smoothing splines of the optimal generalized additive model (GAM) indicated that Secchi depth (SD), total phosphorus (TP) and dissolved oxygen (DO) concentrations, electrical conductivity (EC), chemical oxygen demand (COD), and ratios of total nitrogen (TN) to TP (TN:TP) were the main environmental factors in a moderate nonlinear relationship with cyanobacterial phycocyanin concentrations in East Lake. The shape of the GAM smoother can be used to quantify the relationship between a response variable and an explanatory variable in the scatterplot. Phycocyanin concentrations were sharply and negatively related to both SD and EC when the SD was 20-80 cm and EC was > 270 mg/L. Phycocyanin concentrations increased with concentrations of TP, DO, and COD. Phycocyanin concentrations increased sharply with TP concentrations when TP concentrations were > 0.10 mg/L and approached to a constant when DO concentrations were > 8.20 mg/L. Approximately, 85% of the phycocyanin concentrations were negatively correlated with TN:TP of < 26. In summary, organic compounds and TP were inferred to the key factors limiting the potential growth of cyanobacteria in East Lake. These change points/thresholds of smoothing splines of aforementioned variables may serve as a framework for managing the cyanobacterial growth.
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Affiliation(s)
- Yi-Ming Kuo
- Laboratory of Basin Hydrology and Wetland Eco-restoration, China University of Geosciences, Wuhan, 430074, China.
- School of Environmental Studies, China University of Geosciences, Wuhan, 430074, China.
| | - Jun Yang
- Aquatic EcoHealth Group, Key Laboratory of Urban Environment and Health, Institute of Urban Environment, Chinese Academy of Sciences, Xiamen, 361021, China
| | - Wen-Wen Liu
- Laboratory of Basin Hydrology and Wetland Eco-restoration, China University of Geosciences, Wuhan, 430074, China
- School of Environmental Studies, China University of Geosciences, Wuhan, 430074, China
| | - Enmin Zhao
- Laboratory of Basin Hydrology and Wetland Eco-restoration, China University of Geosciences, Wuhan, 430074, China
- School of Environmental Studies, China University of Geosciences, Wuhan, 430074, China
| | - Ran Li
- Laboratory of Basin Hydrology and Wetland Eco-restoration, China University of Geosciences, Wuhan, 430074, China
- School of Environmental Studies, China University of Geosciences, Wuhan, 430074, China
| | - Liquan Yao
- Laboratory of Basin Hydrology and Wetland Eco-restoration, China University of Geosciences, Wuhan, 430074, China
- School of Environmental Studies, China University of Geosciences, Wuhan, 430074, China
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Kim J, Lyu XM, Lee JJL, Zhao G, Chin SF, Yang L, Chen WN. Metabolomics analysis of Pseudomonas chlororaphis JK12 algicidal activity under aerobic and micro-aerobic culture condition. AMB Express 2018; 8:131. [PMID: 30128639 PMCID: PMC6102160 DOI: 10.1186/s13568-018-0660-x] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/14/2018] [Accepted: 08/11/2018] [Indexed: 12/05/2022] Open
Abstract
Utilization of algicidal bacteria as a biological agent have been receiving significant interest for controlling harmful algal blooms. While various algicidal bacterial strains have been identified, limited studies have explored the influence of bacterial culture conditions on its algicidal activity. Here, the effect of oxygen on the algicidal activity of a novel bacterium JK12, against a model diatom, Phaeodactylum tricornutum (P. tricornutum) was studied. Strain JK12 showed high algicidal activity against P. tricornutum and was identified as Pseudomonas chlororaphis (P. chlororaphis) by 16S ribosomal RNA gene analysis. JK12 culture supernatant exhibited strong algicidal activity while washed JK12 cells showed no obvious activity, indicating that JK12 indirectly attacks algae by secreting extracellular algicidal metabolites. Micro-aerobic culture condition dramatically enhanced the algicidal activity of JK12 by 50%, compared to that cultured under aerobic condition in 24 h. Extracellular metabolomic profiling of JK12 using gas chromatography–mass spectrometry and liquid chromatography–mass spectrometry analysis revealed significantly higher amounts of allantoic acid, urocanic acid, cytidine 2′,3′-cyclic phosphate, uridine 2′,3′-cyclic phosphate, and chlorinated tryptophan in the micro-aerobic culture. This is the first report to demonstrate the important role of oxygen on the algicidal activity of a non-pathogenic strain P. chlororaphis. In addition, the metabolomics analysis provided insights into the algicidal mechanism of P. chlororaphis.
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Yu X, Cai G, Wang H, Hu Z, Zheng W, Lei X, Zhu X, Chen Y, Chen Q, Din H, Xu H, Tian Y, Fu L, Zheng T. Fast-growing algicidal Streptomyces sp. U3 and its potential in harmful algal bloom controls. JOURNAL OF HAZARDOUS MATERIALS 2018; 341:138-149. [PMID: 28777959 DOI: 10.1016/j.jhazmat.2017.06.046] [Citation(s) in RCA: 30] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/27/2017] [Revised: 06/18/2017] [Accepted: 06/20/2017] [Indexed: 06/07/2023]
Abstract
To find the potential algicidal microorganisms and apply them to prevent and terminate harmful algal blooms (HABs), we isolated an actinomycete U3 from Mangrove, which had a potent algicidal effect on the harmful alga Heterosigma akashiwo. It could completely lyse the algal cells by producing active compounds, which were highly sensitive to high temperature and strong alkaline, but resistant to acid. One μg/mL of crude extract of the fermentation supernatant could kill 70% of H. akashiwo cells in 3 d. Unlike most of the other known algicidal Streptomyces, U3 showed strong ability of proliferation with the algal inclusion as the nutrient source. The washed mycelial pellets also gradually exhibited significant algicidal effect during the visible growth in the algal culture. It suggests that U3 could efficiently absorb nutrients from algal culture to support its growth and produce algicidal compounds that might cause the autophagy of algal cells. Therefore, applying U3, as a long-term and environmentally friendly bio-agent to control the harmful blooms of H. akashiwo, would be effective and promising. And the decrease of bioavailable DOM and increase of bio-refractory DOM during the algicidal process of U3 provided new insights into the ecological influence of algicial microorganisms on marine ecosystem.
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Affiliation(s)
- Xiaoqi Yu
- State Key Laboratory of Marine Environmental Science and Key Laboratory of the Ministry of Education for Coastal and Wetland Ecosystems, School of Life Sciences, Xiamen University, Xiamen 361102, China
| | - Guanjing Cai
- State Key Laboratory of Marine Environmental Science and Key Laboratory of the Ministry of Education for Coastal and Wetland Ecosystems, School of Life Sciences, Xiamen University, Xiamen 361102, China
| | - Hui Wang
- Biology Department, College of Life Science, Shantou University, Shantou 515063, China
| | - Zhong Hu
- Biology Department, College of Life Science, Shantou University, Shantou 515063, China
| | - Wei Zheng
- State Key Laboratory of Marine Environmental Science and Key Laboratory of the Ministry of Education for Coastal and Wetland Ecosystems, School of Life Sciences, Xiamen University, Xiamen 361102, China
| | - Xueqian Lei
- State Key Laboratory of Marine Environmental Science and Key Laboratory of the Ministry of Education for Coastal and Wetland Ecosystems, School of Life Sciences, Xiamen University, Xiamen 361102, China
| | - Xiaoying Zhu
- State Key Laboratory of Marine Environmental Science and Key Laboratory of the Ministry of Education for Coastal and Wetland Ecosystems, School of Life Sciences, Xiamen University, Xiamen 361102, China
| | - Yao Chen
- State Key Laboratory of Marine Environmental Science and Key Laboratory of the Ministry of Education for Coastal and Wetland Ecosystems, School of Life Sciences, Xiamen University, Xiamen 361102, China
| | - Qiuliang Chen
- State Key Laboratory of Marine Environmental Science and Key Laboratory of the Ministry of Education for Coastal and Wetland Ecosystems, School of Life Sciences, Xiamen University, Xiamen 361102, China
| | - Hongyan Din
- State Key Laboratory of Marine Environmental Science and Key Laboratory of the Ministry of Education for Coastal and Wetland Ecosystems, School of Life Sciences, Xiamen University, Xiamen 361102, China
| | - Hong Xu
- State Key Laboratory of Marine Environmental Science and Key Laboratory of the Ministry of Education for Coastal and Wetland Ecosystems, School of Life Sciences, Xiamen University, Xiamen 361102, China
| | - Yun Tian
- State Key Laboratory of Marine Environmental Science and Key Laboratory of the Ministry of Education for Coastal and Wetland Ecosystems, School of Life Sciences, Xiamen University, Xiamen 361102, China
| | - Lijun Fu
- Fujian Provincial Key Laboratory of Ecology-Toxicological Effects & Control for Emerging Contaminants, Putian University, Putian 351100, China.
| | - Tianling Zheng
- State Key Laboratory of Marine Environmental Science and Key Laboratory of the Ministry of Education for Coastal and Wetland Ecosystems, School of Life Sciences, Xiamen University, Xiamen 361102, China.
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Sun R, Sun P, Zhang J, Esquivel-Elizondo S, Wu Y. Microorganisms-based methods for harmful algal blooms control: A review. BIORESOURCE TECHNOLOGY 2018; 248:12-20. [PMID: 28801171 DOI: 10.1016/j.biortech.2017.07.175] [Citation(s) in RCA: 136] [Impact Index Per Article: 22.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/31/2017] [Revised: 07/28/2017] [Accepted: 07/29/2017] [Indexed: 06/07/2023]
Abstract
Harmful algal blooms (HABs) are a worldwide problem with numerous negative effects on water systems, which have prompted researchers to study applicable measures to inhibit and control them. This review summarized the current microorganisms-based methods or technologies aimed at controlling HABs. Based on their characteristics, these methods can be divided into two categories: methods based on single-species microorganisms and methods based on microbial aggregates, and four types: methods for rapid decrease of algal cells density (e.g., alga-bacterium and alga-fungus bioflocculation), inhibition of harmful algal growth, lysis of harmful algae (e.g. algicidal bacteria, fungi, and actinomycete), and methods based on microbial aggregates (periphytons and biofilms). An integrative process of "flocculation-lysis-degradation-nutrients regulation" is proposed to control HABs. This review not only offers a systematic understanding of HABs control technologies based on microorganisms but also elicits a re-thinking of HABs control based on microbial aggregates.
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Affiliation(s)
- Rui Sun
- State Key Laboratory of Soil and Sustainable Agriculture, Institute of Soil Sciences, Chinese Academy of Sciences, 71 East Beijing Road, Nanjing 210008, China; College of Resource and Environment, University of Chinese Academy of Sciences, Beijing 100049, China
| | - Pengfei Sun
- State Key Laboratory of Soil and Sustainable Agriculture, Institute of Soil Sciences, Chinese Academy of Sciences, 71 East Beijing Road, Nanjing 210008, China.
| | - Jianhong Zhang
- Resources & Environment Business Dept., International Engineering Consulting Corporation, Beijing 100048, China
| | - Sofia Esquivel-Elizondo
- Swette Center for Environmental Biotechnology at Biodesign Institute, Arizona State University, 1001 South McAllister Avenue, Tempe, AZ 85287-5701, USA
| | - Yonghong Wu
- State Key Laboratory of Soil and Sustainable Agriculture, Institute of Soil Sciences, Chinese Academy of Sciences, 71 East Beijing Road, Nanjing 210008, China
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Gewirtz H, Dilsizian V. Myocardial Viability: Survival Mechanisms and Molecular Imaging Targets in Acute and Chronic Ischemia. Circ Res 2017; 120:1197-1212. [PMID: 28360350 DOI: 10.1161/circresaha.116.307898] [Citation(s) in RCA: 43] [Impact Index Per Article: 6.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/23/2016] [Revised: 02/27/2017] [Accepted: 03/02/2017] [Indexed: 12/17/2022]
Abstract
Myocardial responses to acute ischemia/reperfusion and to chronic ischemic conditions have been studied extensively at all levels of organization. These include subcellular (eg, mitochondria in vitro); intact, large animal models (eg, swine with chronic coronary stenosis); as well as human subjects. Investigations in humans have used positron emission tomographic metabolic and myocardial blood flow measurements, assessment of gene expression and anatomic description of myocardium obtained at the time of coronary artery revascularization, ventricular assist device placement, or heart transplantation. A multitude of genetic, molecular, and metabolic pathways have been identified, which may promote either myocyte survival or death or, most interestingly, both. Many of these potential mediators in both acute ischemia/reperfusion and adaptations to chronic ischemic conditions involve the mitochondria, which play a central role in cellular energy production and homeostasis. The present review is focused on operative survival mechanisms and potential myocardial viability molecular imaging targets in acute and chronic ischemia, especially those which impact mitochondrial function.
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Affiliation(s)
- Henry Gewirtz
- From the Department of Medicine (Cardiology Division), Massachusetts General Hospital, Harvard Medical School, Boston (H.G.); and Department of Diagnostic Radiology and Nuclear Medicine, University of Maryland School of Medicine, Baltimore (V.D.)
| | - Vasken Dilsizian
- From the Department of Medicine (Cardiology Division), Massachusetts General Hospital, Harvard Medical School, Boston (H.G.); and Department of Diagnostic Radiology and Nuclear Medicine, University of Maryland School of Medicine, Baltimore (V.D.).
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Pappu JSM, Gummadi SN. Multi response optimization for enhanced xylitol production by Debaryomyces nepalensis in bioreactor. 3 Biotech 2016; 6:151. [PMID: 28330223 PMCID: PMC4936968 DOI: 10.1007/s13205-016-0467-x] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/11/2016] [Accepted: 06/30/2016] [Indexed: 11/05/2022] Open
Abstract
In this study, the optimization of different process variables—pH (4–6), aeration rate (200–550 rpm) and agitation rate (0.6–1.8 vvm) were investigated using rotating simplex method and uniform design method to enhance xylitol production from xylose by D. nepalensis in a batch stirred tank bioreactor. Maximum xylitol productivity (0.576 g L−1 h−1) was obtained at pH 4.0, agitation 300 rpm and aeration 1.5 vvm by rotating simplex method. Individual optimum values of pH, agitation and aeration are 4.2, 370 rpm and 1.2 vvm, respectively, for productivity, 4.3, 350 rpm and 1.0 vvm, respectively for xylitol concentration and 4.4, 360 rpm and 0.8 vvm, respectively for yield. Using generalized distance approach, the simultaneous optimal values were found to be—pH 4.3, 370 rpm and 0.9 vvm. After multi-response analysis, batch fermentation at optimal operating conditions resulted in enhanced productivity (0.76 g L−1 h−1), xylitol concentration (59.4 g L−1) and yield (0.58 g g−1) with an increase of 76.74 % of xylitol productivity.
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Cai G, Yang X, Lai Q, Yu X, Zhang H, Li Y, Chen Z, Lei X, Zheng W, Xu H, Zheng T. Lysing bloom-causing alga Phaeocystis globosa with microbial algicide: An efficient process that decreases the toxicity of algal exudates. Sci Rep 2016; 6:20081. [PMID: 26847810 PMCID: PMC4742815 DOI: 10.1038/srep20081] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/02/2015] [Accepted: 11/23/2015] [Indexed: 01/04/2023] Open
Abstract
Algicidal microbes could effectively remove the harmful algae from the waters. In this study, we were concerned with the ecological influence of an algicide extracted from Streptomyces alboflavus RPS, which could completely lyse the Phaeocystis globosa cells within two days. In microcosms, 4 μg/mL of the microbial algicide could efficiently remove P. globosa cells without suppressing other aquatic organisms. Bioluminescent assays confirmed that the toxicity of microbial algicide at this concentration was negligible. Interestingly, the toxicity of P. globosa exudates was also significantly reduced after being treated with the algicide. Further experiments revealed that the microbial algicide could instantly increase the permeability of the plasma membrane and disturb the photosynthetic system, followed by the deformation of organelles, vacuolization and increasing oxidative stress. The pre-incubation of N-acetyl cysteine (NAC) verified that the rapid damages to the plasma membrane and photosynthetic system caused the algal death in the early phase, and the increasing oxidative stress killed the rest. The late accumulation and possible release of CAT also explained the decreasing toxicity of the algal culture. These results indicated that this microbial algicide has great potential in controlling the growth of P. globosa on site.
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Affiliation(s)
- Guanjing Cai
- State Key Laboratory of Marine Environmental Science and Key Laboratory of the Ministry of Education for Coastal and Wetland Ecosystems, School of Life Sciences, Xiamen University, Xiamen 361005, China
| | - Xujun Yang
- State Key Laboratory of Marine Environmental Science and Key Laboratory of the Ministry of Education for Coastal and Wetland Ecosystems, School of Life Sciences, Xiamen University, Xiamen 361005, China
| | - Qiliang Lai
- Key Laboratory of Marine Biogenetic Resources, Third Institute of Oceanography, State Oceanic Administration, People's Republic of China
| | - Xiaoqi Yu
- State Key Laboratory of Marine Environmental Science and Key Laboratory of the Ministry of Education for Coastal and Wetland Ecosystems, School of Life Sciences, Xiamen University, Xiamen 361005, China
| | - Huajun Zhang
- State Key Laboratory of Marine Environmental Science and Key Laboratory of the Ministry of Education for Coastal and Wetland Ecosystems, School of Life Sciences, Xiamen University, Xiamen 361005, China
| | - Yi Li
- State Key Laboratory of Marine Environmental Science and Key Laboratory of the Ministry of Education for Coastal and Wetland Ecosystems, School of Life Sciences, Xiamen University, Xiamen 361005, China
| | - Zhangran Chen
- State Key Laboratory of Marine Environmental Science and Key Laboratory of the Ministry of Education for Coastal and Wetland Ecosystems, School of Life Sciences, Xiamen University, Xiamen 361005, China
| | - Xueqian Lei
- State Key Laboratory of Marine Environmental Science and Key Laboratory of the Ministry of Education for Coastal and Wetland Ecosystems, School of Life Sciences, Xiamen University, Xiamen 361005, China
| | - Wei Zheng
- State Key Laboratory of Marine Environmental Science and Key Laboratory of the Ministry of Education for Coastal and Wetland Ecosystems, School of Life Sciences, Xiamen University, Xiamen 361005, China
| | - Hong Xu
- State Key Laboratory of Marine Environmental Science and Key Laboratory of the Ministry of Education for Coastal and Wetland Ecosystems, School of Life Sciences, Xiamen University, Xiamen 361005, China
| | - Tianling Zheng
- State Key Laboratory of Marine Environmental Science and Key Laboratory of the Ministry of Education for Coastal and Wetland Ecosystems, School of Life Sciences, Xiamen University, Xiamen 361005, China
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