Reliable production of biofuels and specifically bioethanol has attracted a significant amount of re-search recently.Within this context,this study deals with dynamic simulation of bioethanol production processes and ...Reliable production of biofuels and specifically bioethanol has attracted a significant amount of re-search recently.Within this context,this study deals with dynamic simulation of bioethanol production processes and in particular aims at developing a mathematical model for describing simultaneous saccharification and co-fermentation （SSCF） of C6 and C5 sugars.The model is constructed by combining existing mathematical mod-els for enzymatic hydrolysis and co-fermentation.An inhibition of ethanol on cellulose conversion is introduced in order to increase the reliability.The mathematical model for the SSCF is verified by comparing the model predic-tions with experimental data obtained from the ethanol production based on kraft paper mill sludge.When fitting the model to the data,only the yield coefficients for glucose and xylose metabolism were fine-tuned,which were found to be 0.43 g·g-1 （ethanol/glucose） and 0.35 g·g-1 （ethanol/xylose） respectively.These promising validation results encourage further model application to evaluate different process configurations for lignocellulosic bioetha-nol technology.展开更多
Anaerobic fermentation is an efficient method to extract phosphorus from excess sludge,thereby facilitating its recovery and mitigating the phosphorus resource shortage.However,the prevalent metal-bound phosphorus spe...Anaerobic fermentation is an efficient method to extract phosphorus from excess sludge,thereby facilitating its recovery and mitigating the phosphorus resource shortage.However,the prevalent metal-bound phosphorus species within sludge was difficult to release into the fermentation liquor.To address this,this study evaluated the enhanced phosphorus release performance from sludge containing iron-phosphorus compounds(Fe-P)via co-fermenting it with agriculture wastes.Specifically,protein-rich feather(Feather Group)and polysaccharide-rich tea residue(Tea Group)was respectively dosed into batch-scale fermentation jar.Results showed that the Feather Group exhibited significantly higher levels of released soluble phosphorus(2.1 folds)and volatile fatty acids(41.4 folds)compared to the Control Group,with concentrations reaching up to 280 mg/L and 9366 mg chemical oxygen demand/L,respectively.The activities ofα-glucosidase,neutral protease and acetate kinase in the Feather group were increased by 11.1%,92.3%and 37.6%,respectively,compared with the Control group.Methanogen abundance decreased while hydrolytic acid-producing bacteria and iron-reducing bacteria increased significantly after supplying agricultural wastes.Metagenomic analysis demonstrated a significant increase in genes related to acetic acid synthesis.Mechanism elucidation suggested that increased iron-reducing bacteria abundance promoted Fe3+reduction into Fe2+,thus enhancing phosphorus release from Fe-P compounds.This work may provide valuable information for developing effective strategy to extract phosphorus resource from complex environmental wastes.展开更多
Abstract： Daqu distiller＇s grains were co-fermented as raw materials by Trichoderma.koningii and Trichosporon cutaneum to produce microbial oils, which can provide raw materials for bio-diesel development. The singl...Abstract： Daqu distiller＇s grains were co-fermented as raw materials by Trichoderma.koningii and Trichosporon cutaneum to produce microbial oils, which can provide raw materials for bio-diesel development. The single factor tests were used to investigate the effects of ratio of strains, inoculum size, culture temperature and culture time on the production of microbial oils. The best processing conditions were obtained by orthogonal test through measuring the content of microbial oils in product. The result shows that the microbial oils content of the co-fermented product under the ratio of Trichoderma.koningii to Trichosporon cutaneum of 1：1, the inoculum size of strains of 11% at 28 ℃ for 6 d is 7.15 g/L. It is shown that the production of microbial oils co-fermented by Trichoderma.koningii and Trichosporon cutaneum with Daqu distiller＇s grains is possible. The research provides a new idea for the reuse of Daqu distiller＇s grains and also provides a new way for the development of microbial oils.展开更多
In recent years,volatile fatty acid(VFA)production through anaerobic fermentation of sewage sludge,instead of methane production,has been regarded as a high-value and promising roadmap for sludge stabilization and res...In recent years,volatile fatty acid(VFA)production through anaerobic fermentation of sewage sludge,instead of methane production,has been regarded as a high-value and promising roadmap for sludge stabilization and resource recovery.This review first presents the effects of some essential factors that influence VFA production and composition.In the second part,we present an extensive analysis of conventional pretreatment and co-fermentation strategies ultimately addressed to improving VFA production and composition.Also,the effectiveness of these approaches is summarized in terms of sludge degradation,hydrolysis rate,and VFA production and composition.According to published studies,it is concluded that some pretreatments such as alkaline and thermal pretreatment are the most effective ways to enhance VFA production from sewage sludge.The possible reasons for the improvement of VFA production by different methods are also discussed.Finally,this review also highlights several current technical challenges and opportunities in VFA production with spectrum control,and further related research is proposed.展开更多
The tolerance of Lactiplantibacillus plantarum(L.plantarum)to iso-α-acid is critical to sour beer production,and the mechanism of its tolerance to iso-α-acid on cell phenotype is still uncovered.In current study,the...The tolerance of Lactiplantibacillus plantarum(L.plantarum)to iso-α-acid is critical to sour beer production,and the mechanism of its tolerance to iso-α-acid on cell phenotype is still uncovered.In current study,the tolerance of L.plantarum J6 was enhanced by adaptive laboratory evolution(ALE).And the stress response of L.plantarum J6-6 was analyzed by the changes of intracellular protein,cell membrane fatty acid composition and permeability.The strain J6-6 with iso-α-acid(25 mg/L)displayed an increased unsaturation of fatty acids.The protein involved in glycolysis pathway,nucleotide,amino acid and energy metabolism,would enhance the tolerance of J6-6.In addition,ALE can reduce the damage and improve the viability of iso-α-acid.The application of J6-6 in sour beer can easily control the entire fermentation,with more sweet-sour taste and better flavor.This study provides a well-defined target of easy-to-control sour beer.展开更多
基金Supported by the Mexican National Council for Science and Technology (CONACyT# 118903)the Danish Research Council for Technology and Production Sciences (FTP# 274-07-0339)
文摘Reliable production of biofuels and specifically bioethanol has attracted a significant amount of re-search recently.Within this context,this study deals with dynamic simulation of bioethanol production processes and in particular aims at developing a mathematical model for describing simultaneous saccharification and co-fermentation （SSCF） of C6 and C5 sugars.The model is constructed by combining existing mathematical mod-els for enzymatic hydrolysis and co-fermentation.An inhibition of ethanol on cellulose conversion is introduced in order to increase the reliability.The mathematical model for the SSCF is verified by comparing the model predic-tions with experimental data obtained from the ethanol production based on kraft paper mill sludge.When fitting the model to the data,only the yield coefficients for glucose and xylose metabolism were fine-tuned,which were found to be 0.43 g·g-1 （ethanol/glucose） and 0.35 g·g-1 （ethanol/xylose） respectively.These promising validation results encourage further model application to evaluate different process configurations for lignocellulosic bioetha-nol technology.
基金supported by the“Pioneer”and“Leading Goose”R&D Program of Zhejiang(No.2023C03149).
文摘Anaerobic fermentation is an efficient method to extract phosphorus from excess sludge,thereby facilitating its recovery and mitigating the phosphorus resource shortage.However,the prevalent metal-bound phosphorus species within sludge was difficult to release into the fermentation liquor.To address this,this study evaluated the enhanced phosphorus release performance from sludge containing iron-phosphorus compounds(Fe-P)via co-fermenting it with agriculture wastes.Specifically,protein-rich feather(Feather Group)and polysaccharide-rich tea residue(Tea Group)was respectively dosed into batch-scale fermentation jar.Results showed that the Feather Group exhibited significantly higher levels of released soluble phosphorus(2.1 folds)and volatile fatty acids(41.4 folds)compared to the Control Group,with concentrations reaching up to 280 mg/L and 9366 mg chemical oxygen demand/L,respectively.The activities ofα-glucosidase,neutral protease and acetate kinase in the Feather group were increased by 11.1%,92.3%and 37.6%,respectively,compared with the Control group.Methanogen abundance decreased while hydrolytic acid-producing bacteria and iron-reducing bacteria increased significantly after supplying agricultural wastes.Metagenomic analysis demonstrated a significant increase in genes related to acetic acid synthesis.Mechanism elucidation suggested that increased iron-reducing bacteria abundance promoted Fe3+reduction into Fe2+,thus enhancing phosphorus release from Fe-P compounds.This work may provide valuable information for developing effective strategy to extract phosphorus resource from complex environmental wastes.
基金Project(10A110) supported by Hunan Provincial Education Department of ChinaProject(2010JT4055) supported by Hunan Provincial Science & Technology Department of China
文摘Abstract： Daqu distiller＇s grains were co-fermented as raw materials by Trichoderma.koningii and Trichosporon cutaneum to produce microbial oils, which can provide raw materials for bio-diesel development. The single factor tests were used to investigate the effects of ratio of strains, inoculum size, culture temperature and culture time on the production of microbial oils. The best processing conditions were obtained by orthogonal test through measuring the content of microbial oils in product. The result shows that the microbial oils content of the co-fermented product under the ratio of Trichoderma.koningii to Trichosporon cutaneum of 1：1, the inoculum size of strains of 11% at 28 ℃ for 6 d is 7.15 g/L. It is shown that the production of microbial oils co-fermented by Trichoderma.koningii and Trichosporon cutaneum with Daqu distiller＇s grains is possible. The research provides a new idea for the reuse of Daqu distiller＇s grains and also provides a new way for the development of microbial oils.
基金supported by the National Natural Science Foundation of China(No.51578068)"One Thousand Talent Plan" Youth Program
文摘In recent years,volatile fatty acid(VFA)production through anaerobic fermentation of sewage sludge,instead of methane production,has been regarded as a high-value and promising roadmap for sludge stabilization and resource recovery.This review first presents the effects of some essential factors that influence VFA production and composition.In the second part,we present an extensive analysis of conventional pretreatment and co-fermentation strategies ultimately addressed to improving VFA production and composition.Also,the effectiveness of these approaches is summarized in terms of sludge degradation,hydrolysis rate,and VFA production and composition.According to published studies,it is concluded that some pretreatments such as alkaline and thermal pretreatment are the most effective ways to enhance VFA production from sewage sludge.The possible reasons for the improvement of VFA production by different methods are also discussed.Finally,this review also highlights several current technical challenges and opportunities in VFA production with spectrum control,and further related research is proposed.
基金supported by the National Natural Science Foundation of China(31871785)the Program of Introducing Talents of Discipline to Universities(111 Project)(111-2-06).
文摘The tolerance of Lactiplantibacillus plantarum(L.plantarum)to iso-α-acid is critical to sour beer production,and the mechanism of its tolerance to iso-α-acid on cell phenotype is still uncovered.In current study,the tolerance of L.plantarum J6 was enhanced by adaptive laboratory evolution(ALE).And the stress response of L.plantarum J6-6 was analyzed by the changes of intracellular protein,cell membrane fatty acid composition and permeability.The strain J6-6 with iso-α-acid(25 mg/L)displayed an increased unsaturation of fatty acids.The protein involved in glycolysis pathway,nucleotide,amino acid and energy metabolism,would enhance the tolerance of J6-6.In addition,ALE can reduce the damage and improve the viability of iso-α-acid.The application of J6-6 in sour beer can easily control the entire fermentation,with more sweet-sour taste and better flavor.This study provides a well-defined target of easy-to-control sour beer.
