Background Formolase(FLS)is a computationally designed enzyme that catalyzes the carboligation of two or three C1 formaldehyde molecules into C2 glycolaldehyde or C3 dihydroxyacetone(DHA).FLS lays the foundation for s...Background Formolase(FLS)is a computationally designed enzyme that catalyzes the carboligation of two or three C1 formaldehyde molecules into C2 glycolaldehyde or C3 dihydroxyacetone(DHA).FLS lays the foundation for several artificial carbon fixation and valorization pathways,such as the artificial starch anabolic pathway.However,the application of FLS is limited by its low catalytic activity and product promiscuity.Findings FLS,designed and engineered based on benzoylformate decarboxylase from Pseudomonas putida,was selected as a candidate for modification.To evaluate its catalytic activity,25 residues located within an 8Ådistance from the active center were screened using single-point saturation mutagenesis.A screening approach based on the color reaction of the DHA product was applied to identify the desired FLS variants.After screening approximately 5,000 variants(approximately 200 transformants per site),several amino acid sites that were not identified by directed evolution were found to improve DHA formation.The serine-to-phenylalanine substitution at position 236 improved the activity towards DHA formation by 7.6-fold.Molecular dynamics simulations suggested that the mutation increased local hydrophobicity at the active site,predisposing the cofactor-C2 intermediate to nucleophilic attack by the third formaldehyde molecule for subsequent DHA generation.Conclusions This study provides improved FLS variants and valuable information into the influence of residues adjacent to the active center affecting catalytic efficiency,which can guide the rational engineering or directed evolution of FLS to optimize its performance in artificial carbon fixation and valorization.展开更多
Tamarind seeds are one of the waste crops that were usually given to pigs and the use of spontaneous bioconversion can increase digestibility. The research objective was to evaluate nutrient digestibility spontaneous ...Tamarind seeds are one of the waste crops that were usually given to pigs and the use of spontaneous bioconversion can increase digestibility. The research objective was to evaluate nutrient digestibility spontaneous bioconversion of tamarind seeds at Timor Local Pig. The study was conducted from May to July 2017 in the Laboratory of Animal Production and Reproduction of Kupang State Agricultural Polytechnic. The study used local male pigs grower phase of 3-4 months old aged and used a randomized block design with four treatments and five replications, namely R0 = ration without bioconversion spontaneous tamarind seeds, R1 = rations containing 10% bioconversion spontaneous tamarind seeds, R2 = ration containing 20% bioconversion spontaneous tamarind seeds, R3 = ration containing 30% bioconversion spontaneous tamarind seeds. The variables measured were dry matter digestibility, crude protein, crude fiber, and tannins. The results showed that spontaneous bioconversion of tamarind seeds affected significantly （p 〈 0.01） on dry matter digestibility, crude protein, ether extract, ash, and tannin digestibility but no effect （p 〉 0.05） on crude fiber digestibility. It was concluded that the use of tamarind seeds spontaneous bioconversion in livestock rations of local pigs Timor should be as much as 20%.展开更多
CO2 is not only the most important greenhouse gas but also an important resource of elemental carbon and oxygen.From the perspective of resource and energy strategy,the conversion of CO2 to chemicals driven by renewab...CO2 is not only the most important greenhouse gas but also an important resource of elemental carbon and oxygen.From the perspective of resource and energy strategy,the conversion of CO2 to chemicals driven by renewable energy is of significance,since it can not only reduce carbon emission by the utilization of CO2 as feedstock but also store low-grade renewable energy as high energy density chemical energy.Although studies on photoelectrocatalytic reduction of CO2 using renewable energy are increasing,artificial bioconversion of CO2 as an important novel pathway to synthesize chemicals has attracted more and more attention.By simulating the natural photosynthesis process of plants and microorganisms,the artificial bioconversion of CO2 can efficiently synthesize chemicals via a designed and constructed artificial photosynthesis system.This review focuses on the recent advancements in artificial bioreduction of CO2,including the key techniques,and artificial biosynthesis of compounds with different carbon numbers.On the basis of the aforementioned discussions,we present the prospects for further development of artificial bioconversion of CO2 to chemicals.展开更多
This study was undertaken to screen the filamentous fungi isolated from its relevant habitats(wastewater, sewage sludge and sludge cake) for the bioconversion of domestic wastewater sludge. A total of 35 fungal strain...This study was undertaken to screen the filamentous fungi isolated from its relevant habitats(wastewater, sewage sludge and sludge cake) for the bioconversion of domestic wastewater sludge. A total of 35 fungal strains were tested against wastewater sludge (total suspended solids, TSS 1%—5% w/w) to evaluate its potentiality for enhancing the biodegradability and dewaterability using liquid state bioconversion(LSB) process. The strains were divided into five groups i.e. Penicillium, Aspergillus, Trichoderma, Basidiomycete and Miscellaneous, respectively. The strains WWZP1003, SCahmA103, SCahmT105 and PC-9 among their respective groups of Penicillium, Aspergillus, Trichoderma and Basidiomycete played potential roles in terms of separation(formation of pellets/flocs/filaments), biodegradation(removal of COD) and filtration(filterability) of treated domestic wastewater sludge. The Miscellaneous group was not considered due to its unsatisfactory results as compared to the other groups. The pH value was also influenced by the microbial treatment during fermentation process. The filterability of treated sludge was improved by fungal treatment, and lowest filtration time was recorded for the strain WWZP1003 and SCahmA103 of Penicillium and Aspergillus groups respectively compared with other strains.展开更多
Production of 6-aminopenicillanic acid (6-APA) by hydrolysis using penicillin acylase (PA) was studied as a model of an enzymatic emulsion liquid membrane (ELM) process. The loss of PA activity was examined for variou...Production of 6-aminopenicillanic acid (6-APA) by hydrolysis using penicillin acylase (PA) was studied as a model of an enzymatic emulsion liquid membrane (ELM) process. The loss of PA activity was examined for various membrane compositions (organic solvent, surfactant, carrier). The effects of some experimental variables on the stability of emulsion were investigated. It was found that the choice of organic solvent greatly affected the stability of the emulsion. Increasing the concentration of the carrier in the membrane phase increases the transfer rate of substrate and products but also has a destabilizing effect on the emulsion. The recovery of 6-APA obtained by a di-carrier system (N263-N1923) was much higher than those when either of the di-carriers was used separately. The whole process was controlled both by the enzymatic reaction rate and by the transfer rate of the substrate and the products, however, the ratio of them could be changed by varying the composition of the system. For an optimum condition, it was obtained that the recovery ratio of 6-APA was over 80% and the conversion of benzyl penicillin (PG) was up to 90% in the external phase after 30 minutes. Meanwhile, the breakage percentage of the emulsion was less than 2%.展开更多
Parthenium hysterophorus is a globally recognized invasive alien weed that prominently colonizes grazing areas and cultivated lands causing adverse effect on crop production. Major allelochemicals released from parthe...Parthenium hysterophorus is a globally recognized invasive alien weed that prominently colonizes grazing areas and cultivated lands causing adverse effect on crop production. Major allelochemicals released from parthenium include sesqueterpene lactones and phenolic acids. Among these the presence of caffeic, vanillic and ferulic acids is of industrial significance as they possess potent free radical scavenging and anticancer activities. This study reports for the first time, high total phenolic acid content (20.82 ± 0.82 mg GAE/g dry sample) in parthenium. The GC-MS analysis indicated the presence of ferulic, p-coumaric, vanillic and gallic acid as major phenolic components. Free radical scavenging activity of the phenolic acids extract gave an EC50 value 130.4 μg/ml when measured using DPPH assay. Anticancer activity of parthenium phenolic extract against A-498 (IC50 0.5237 μg/ml) and MDA-MB231 (IC50 and 0.2685 μg/ml) cancerous cell lines indicated its potential to be used as anticancer agent.展开更多
Since 1993, China has become a net importer of energy from a net exporter. The total energy con- sumption has been greater than the total supply, and the external dependence of the energy demand increases rapidly. Ch...Since 1993, China has become a net importer of energy from a net exporter. The total energy con- sumption has been greater than the total supply, and the external dependence of the energy demand increases rapidly. China＇ s crude oil import volume and imports amount reached 253.78 million tons and 196.664 billion US dollars in 2011, with a growth rate of 6 % and 45.3 %, respectively, year-on-year. The significant increase in demand for oil and the caused structural contradictions are increasingly becoming the greatest challenge for China＇ s energy security. The energy crisis has not only touched everyone＇ s nerves, but also sparked a strong desire to find alternative energy.展开更多
Switchgrass (Panicum virgatum L.) is a native warm-season grass and it is one of potential bioenergy crops. The objectives of this study were to: 1) assess the best performing switchgrass genotype suitable for Kansas ...Switchgrass (Panicum virgatum L.) is a native warm-season grass and it is one of potential bioenergy crops. The objectives of this study were to: 1) assess the best performing switchgrass genotype suitable for Kansas soil and climatic condition in the USA, 2) determine the correlation between plant height or tiller numbers per plant and dry biomass of various switchgrass genotypes, and 3) assess a bioconversion efficiency of certain varieties of switchgrass. Twenty-two different genotypes of seedlings were allowed to grow in cones for 30 days under controlled environments. The genotype Cave-in-Rock was the shortest among the genotypes. Significant difference in number of tillers per plant was observed among the genotypes. The genotypes Alamo recorded the highest numbers of tiller plant-1 and the genotype Cave-in-Rock had the lowest numbers of tiller plant-1 compared with other genotypes. The genotypes Alamo, NL 94 C2-2, NL 94 C2-3, NSL 2009-1 and NSL 2009-2 had increased above ground biomass compared with other genotypes. The correlation study indicates that there was a significant positive correlation between number of tillers per plant and per plant dry weight (R2 = 0.93), number of tillers per plant and plant height (R2 = 0.94), and plant height and per plant dry weight (R2 = 0.82). Based on the biomass composition, the SWG 2007-2 genotype was the promising switchgrass line for the bioconversion through the sugar platform route due to high carbohydrate and low lignin content. On the other hand, the high biomass yield per unit area of field in NL 94 C2-1 led this genotype with the highest total carbohydrate yield per unit area of field despite the lowest total carbohydrate content in the genotype. These results are pertinent for crop breeders to develop the most promising switchgrass line with high biomass yield and high bioconversion efficiency to produce biofuel through the sugar platform route.展开更多
The bioconversion process of municipal solid waste was assessed on the basis of the results obtained from the biodrying reactor working at a full industrial scale.The bio-reactor is a part of mechanical-biological ins...The bioconversion process of municipal solid waste was assessed on the basis of the results obtained from the biodrying reactor working at a full industrial scale.The bio-reactor is a part of mechanical-biological installation following mechanical stage.The bio-reactor was equipped with measuring devices allowing the analysis of the parameters like:temperature both inside the waste and also air above the waste and also the humidity of waste during the 14 days of the biodrying process.The kinetics of bioconversion was assessed basing on measured the loss of ignition(LOI)parameter detected during the biodrying process.The LOI value of the samples varied from 17.03%Am.to 30.34%d.m.depending on the location inside the reactor.The estimated kinetic rate constant kT of the bioconversion of biomass in the industrial reactor was kT=0.3141.In analyzed case study the calorific value of product leaving the full-scale bio-reactor is too low to use this product as an alternative fuel.As w'as stated the reason of this is too low a share of the carbon-rich fraction in the feedstock.展开更多
The main objective of this investigation was to study the time effect during solid state bioconversion (SSB) on total phenolics content (TPC) and antioxidant activity (AoxA) of common beans to improve antihypertensive...The main objective of this investigation was to study the time effect during solid state bioconversion (SSB) on total phenolics content (TPC) and antioxidant activity (AoxA) of common beans to improve antihypertensive functionality. Cooked cotyledons of dehulled common beans were inoculated with a suspension of R. oligosporus NRRL 2710 (1 × 106 spores/mL), and incubated at 35℃ for times of 24, 36, 48, 60, 72, 84, 96 and 108 h (after 108 h the cotyledons showed off odor). Flours from bioprocessed dehulled common bean from each incubation time were blended with their corresponding milled seed coats. The best time for producing bioprocessed common bean (added with seed coats) functional flour with the highest AoxA (ORAC value = 17,468 μmol Trolox equivalents (TE)/100 gsample, dw;ABTS value = 13,505 μmol TE/100 gsample, dw) was 108 h. The SSB process substantially increased TPC and total hydrophilic AoxA and antihypertensive potential of common beans in 2.24, 2.45 - 2.73 and 6769 times, respectively. Proteins hydrolyzates from unprocessed whole and bioprocessed (108 h) common beans had IC50 [concentration needed to inhibit 50% the activity of angiotensin converting enzyme (ACE)] of 79.2 and 0.0117 μg/mL, respectively. The SSB is an efective strategy to improve the TPC of common beans for enhanced functionality with improved antioxidant activity and antihypertensive potential.展开更多
This study presented new insights into the sustainable conversion of total petroleum hydrocarbon(TPHC)into polyhydroxyalkanoates(PHAs)using wetland microbial fuel cells(WMFCs).The main innovations included the followi...This study presented new insights into the sustainable conversion of total petroleum hydrocarbon(TPHC)into polyhydroxyalkanoates(PHAs)using wetland microbial fuel cells(WMFCs).The main innovations included the following two points:(1)The integration of bioelectricity generation with efficient PHA production further underscored the potential of electroactive biofilms as a sustainable platform for simultaneous TPHC biotransformation,bioelectricity recovery and PHA production.(2)The interactive dynamics of PHAs,metabolites,extracellular polymeric substances(EPS)and microorganisms during the formation and stabilization of electroactive biofilms provided novel insights into microbial strategies for carbon utilization.As the electroactive biofilm formed and stabilized,the current density enhanced significantly from 0 to 101 mA m2,then stabilized,and finally dropped to 3.51 mA m2.Similarly,the power density showed a trend of increasing in the initial stage,maintaining in the middle stage,and then descending in the later stage.The production of six types of PHAs was identified:poly(3-hydroxybutyrate)[P(3HB)],poly(3-hydroxyvalerate)[P(3HV)],poly(3-hydroxybutyrate-co-3-hydroxyvalerate)[P(3HB-co-3HV)],poly[(R)-3-hydroxybutyrate-co-(R)-3-hydroxyhexanoate][P(3HB-co-3HHX)],poly(3-hydroxyhexadecanoate)[P(3HHD)]and poly(3-hydroxyoctadecanoate)[P(3HOD)],highlighting the metabolic flexibility of electroactive biofilms.The total PHA content was initially undetectable(days 0–4),gradually increased(days 4–28),rose rapidly(days 28–48),gradually increased and descended(days 48–68).The maximum PHA content of 0.664 g g⁻1 DCW achieved highlighted the dual functionality of WMFCs in bioelectricity production and PHA biosynthesis,distinguishing it from conventional MFC applications.The TPHC biodegradation ratio demonstrated a gradual increase(days 0–28),with a more pronounced rise(days 28–48),and a gradual rise to 76.1%(days 48–68).Throughout the process,the metabolite volatile fatty acids(VFAs)produced were primarily acetate,propionate,butyrate and valerate.The trend of VFA production from days 0–56 closely followed that of TPHC biodegradation.The trend of tyrosine/tryptophan proteins in EPS was aligned with that of biofilm thickness.The strong correlation between the increase in the biofilm thickness and the intensity and peak height of tyrosine/tryptophan proteins during the first 20 days suggested that these proteins were integral to the structural integrity of the biofilms,and from days 20–64,the minimal variation in their intensity and peak height indicated that the biofilms had reached a relatively stable state.The biofilms in turn provided a stable microbial substrate and energetic support for the subsequent efficient synthesis of PHA.During the early phase,the dual-function bacteria,such as Pseudomonas,Bacillus,Acinetobacter and Desulfosarcina,prioritized electron transfer and bioelectricity production using available carbon sources.As bioelectricity generation became less critical in the later phase,the bacteria shifted to intracellular PHA accumulation,transitioning from bioelectricity production to PHA biosynthesis.Finally,a comprehensive network connecting functional microorganisms with bioelectricity production,PHA content,TPHC biodegradation,VFA production and EPS peak height was established.Overall,these findings provided valuable insights into the dynamic interactions and metabolic strategies of electroactive biofilms in WMFCs,highlighting their potential for the efficient bioconversion of PHCs into PHAs.展开更多
The study investigated the enhanced production of 2-hydroxybutyric acid(2-HBA)from threonine using a two-step whole-cell bioconversion by recombinant Escherichia coli BL21(DE3)overexpressing threonine dehydratase and ...The study investigated the enhanced production of 2-hydroxybutyric acid(2-HBA)from threonine using a two-step whole-cell bioconversion by recombinant Escherichia coli BL21(DE3)overexpressing threonine dehydratase and keto-reductase.To address the rate-limiting step posed by NADH regeneration for the keto-reductase reaction converting 2-ketobutyric acid(2-KBA)to 2-HBA,formate dehydrogenase from Candida boidinii was overexpressed under the T7 promoter,resulting in a high titer of 1015 mM and a yield of 0.70 mol/mol.Furthermore,the yield was improved by disrupting three enzymes responsible for the degradation of the intermediate(2-KBA),pyruvate-formate lyase(PflB),pyruvate oxidase(PoxB),and pyruvate dehydrogenase complex(PDHc),leading to an impressive yield of 0.99 mol/mol,closely approaching the theo-retical maximum of 1.00 mol/mol.The triple mutant,designed to prevent 2-KBA degradation,achieved a remarkable titer of 1,400 mM and volumetric productivity of 58 mmol/L/h.To the best of our knowledge,this achievement represents the highest reported titer and yield for 2-HBA production to date.展开更多
Anaerobic oxidation of methane(AOM)can contribute to reducing methane emissions in landfills;however,the AOM rates vary depending on the inoculum source.This study addressed the capacity of AOM of a fermentative micro...Anaerobic oxidation of methane(AOM)can contribute to reducing methane emissions in landfills;however,the AOM rates vary depending on the inoculum source.This study addressed the capacity of AOM of a fermentative microbial community derived from a reactor treatingmunicipal solidwastes.First,the inoculum’s autotrophic capacitywas verified using a gasmixture of 75% CO_(2) and 25% H_(2).Results demonstrated that the fermentative microbial community reached amaximum CO_(2) consumption rate of 22.5±1.2 g CO_(2)/(m^(3)·h),obtaining acetate as the main product.Then,the inoculum was grown on a gas mixture of 50%CH_(4),35%CO_(2),and 15%N_(2),using iron(Fe^(3+))as the electron acceptor.The AOM rates increased over time and peaked at 3.1±0.9 g CH_(4)/(m^(3)·h)by 456 h with the simultaneous consumption of CO_(2).Acetate was the main product,with amaximum concentration of 180±9mg/L.By 408 h,a bacterial cluster of indicator species correlated with the AOM rates,including to Rhodobactereceae(r=0.80),Oceanicola(r=0.80),Propionicicella(r=0.77),Christensenellaceae(r=0.58),Oscillospiraceae(r=0.53),Mobilitalea(r=0.66),Hungateiclostridiaceae(r=0.46),and Izemoplasmatales(r=0.77).Methanosarcina,Methanobacterium,and Methanoculleus correlated with the AOM and CO_(2) consumption rates.A co-occurrence network analysis showed that Methanosarcina positively interacted with syntrophic bacteria like Christensenellaceae and Acinetobacter and diverse heterotrophic bacteria.This study demonstrated the feasibility of obtaining a CH_(4)-oxidizing microbial community in 16 days,exhibiting AOM rates higher than those reported for soils.展开更多
Nanocellulose has various outstanding properties and great potential for replacing petrochemical products.The utilization of lignocellulose to produce nanocellulose is of great significance to the sustainable developm...Nanocellulose has various outstanding properties and great potential for replacing petrochemical products.The utilization of lignocellulose to produce nanocellulose is of great significance to the sustainable development of the economy and society.However,the direct extraction of nanocellulose from lignocellulose by chemical method is challenged by toxic chemicals utilization,energy and time consumption,and waste water generation.Therefore,this paper addressed the conversion of lignocellulosic biomass into bacterial nanocellulose(BNC)by the biological method.Moreover,this article highlights the recent advances in potentials and challenges of lignocellulosic biomass for BNC production through the bioconversion process,including biomass pretreatment,enzymatic hydrolysis,glucose and xylose fermentation,GA accumulation,and inhibitor tolerant.The development in metabolic and evolutionary engineering to enhance the production capacity of BNC-producing strain is also discussed.It is expected to provide guidance on the effective bioproduction of nanocellulose from lignocellulosic biomass.展开更多
Tetrahydrocurcumin(THCu)is one of the major reduction metabolites of curcumin(CUR),which is a well-known yellow food pigment from turmeric with strong antioxidant,anti-inflammatory,and antibacterial properties.THCu ex...Tetrahydrocurcumin(THCu)is one of the major reduction metabolites of curcumin(CUR),which is a well-known yellow food pigment from turmeric with strong antioxidant,anti-inflammatory,and antibacterial properties.THCu exhibits better solubility,stability,bioavailability than CUR and similar pharmacological activities.In recent years,the market demand for the colorless THCu has a large growth for its application in the field of functional foods and cosmetics due to its strong antioxidant and skin-whitening function.Current industrial production mainly relies on chemical synthesis.The environmental-friendly and good-selectivity synthesis methods like microbial/enzymatic transformation might be better alternative.Several microorganisms have been reported with the capability of CUR reduction.Good-selectivity enzymes also have been characterized like alcohol dehydrogenase from equine liver and curcumin reductase from gut bacteria.This review focuses on the production technology of THCu and summarizes researches on its new chemical synthesis strategies,possible bioconversion methods,detection methods and potential applications.展开更多
A cholesterol oxidase(COD)was hybridized with Ca^(2+),Zn^(2+),Al^(3+),Fe^(2+) and Mn^(2+).After precipitation with PO_(4)^(3-) at 4℃ for 72 h,the resulting pellets were freeze-dried.In scanning electron microscopy as...A cholesterol oxidase(COD)was hybridized with Ca^(2+),Zn^(2+),Al^(3+),Fe^(2+) and Mn^(2+).After precipitation with PO_(4)^(3-) at 4℃ for 72 h,the resulting pellets were freeze-dried.In scanning electron microscopy assays,the metal-COD complexes revealed flower-like or granular structures after hybridization.Fourier transform infrared spectroscopy assay revealed the characteristic peaks of both the enzyme and metal materials.X-ray diffraction analysis indicated that COD was encapsulated in CaHPO_(4)·2H_(2)O-,Zn_(3)(PO_(4))_(2)·4H_(2)O-,AlPO_(4-),FeP_(4-) and Mn_(3)(PO_(4))_(2)·3H_(2)O-based nanostructures,respectively.Differential scanning calorimetry assay indicated significant increases in thermo-denaturation temperatures from 60.5℃ to 167.02℃,167.02℃,137.70℃,172.85℃ and 160.99℃,respectively.Using steroid derivatives as substrates,this enzyme could convert cholesterol,pregnenolone,dehydroepiandrosterone,ergosterol,b-sitosterol and stigmasterol to related single products.Hybridization in metal-based nanostructures could significantly enhance the initial conversion ratio and reaction stability of the enzyme.In addition,substrate selectivity could be affected by various metal materials.Briefly,using Ca^(2+),Zn^(2+),Al^(3+),Fe^(2+) and Mn^(2+) as hybrid raw materials could help to encapsulate COD in related metal-enzyme nanostructures,and could help to promote the stability and tolerant properties of the enzyme,while also enhancing its catalytic characteristics.展开更多
Bioconversion is a biological process by which organic materials are converted into products with higher biological and commercial value.During its larval stage the black soldier fly Hermetia illucens is extremely vor...Bioconversion is a biological process by which organic materials are converted into products with higher biological and commercial value.During its larval stage the black soldier fly Hermetia illucens is extremely voracious and can feed on a wide vari-ety of organic materials.To study the impact of different fruit byproducts on the insect's growth,final larval biomass,substrate reduction,bioconversion parameters,and larval nu-tritional composition,10000 black soldier fly larvae(BSFL)were reared on 7.0 kg of one of three substrates(strawberry,tangerine,or orange)or on a standard diet as a control.The results highlight that BSFL can successfully feed and grow on each of these diets,though their development time,growth rate,and final biomass were differently impacted by the substrates,with strawberry being the most suitable.The lipid and protein contents of BSFL were similar among larvae fed on different substrates;however,major differences were detected in ash,micronutrient,fiber,fatty acid,and amino acid contents.Overall,the results indicate that fruit waste management through the BSFL bioconversion process rep-resents a commercially promising resource for regional and national agrifood companies.Our study offers new perspectives for sustainable and environmentally friendly industrial development by which fruit byproducts or waste might be disposed of or unconventionally enhanced to create secondary products of high biological and economic value,including BSFL biomass as animal feed or,in perspective,as alternative protein source for human nutrition.展开更多
Biogenic coalbed methane(BCBM)reservoirs aim to produce methane from in situ coal deposits following microbial conversion of coal.Success of BCBM reservoirs requires economic methane production within an acceptable ti...Biogenic coalbed methane(BCBM)reservoirs aim to produce methane from in situ coal deposits following microbial conversion of coal.Success of BCBM reservoirs requires economic methane production within an acceptable timeframe.The work reported here quantifies the findings of previously published qualitative work,where it was found that bioconversion induces strains in the pore,matrix and bulk scales.Using imaging and dynamic strain monitoring techniques,the bioconversion induced strain is quantified here.To understand the effect of these strains from a reservoir geomechanics perspective,a corresponding poromechanical model is developed.Furthermore,findings of imaging experiments are validated using core-flooding flow experiments.Finally,expected field-scale behavior of the permeability response of a BCBM operation is modeled and analyzed.The results of the study indicated that,for Illinois coals,bioconversion induced strains result in a decrease in fracture porosity,resulting in a detrimental permeability drop in excess of 60%during bioconversion,which festers itself exponentially throughout its producing life.Results indicate that reservoirs with high initial permeability that will support higher Darcian flowrates,would be better suited for coal bioconversion,thereby providing a site-selection criteria for BCBM operations.展开更多
Fungal endophytes,as an untapped resource of glycoside hydrolase biocatalysts,need to be further developed.Mogroside V,the primary active compound in Siraitia grosvenorii fruit,can be converted into other various bioa...Fungal endophytes,as an untapped resource of glycoside hydrolase biocatalysts,need to be further developed.Mogroside V,the primary active compound in Siraitia grosvenorii fruit,can be converted into other various bioactive mogrosides by selective hydrolysis of glucose residues at C3 and C24 positions.In present study,20 fungal strains were randomly selected from our endophytic fungal strain library to assess their capability for mogroside V transformation.The results revealed that relatively high rate(30%)endophytic fungal strains exhibited transformative potential.Further analysis indicated that endophytic fungi could produce abundant mogrosides,and the pathways for biotransforming mogroside V showed diverse.Among the given fungal endophytes,Aspergillus sp.S125 almost completely converted mogroside V into the end-products mogroside II A and aglycone within just 2 days of fermentation;Muyocopron sp.A5 produced rich intermediate products,including siamenoside I,and the end-product mogroside II E.Subsequently,we optimized the fermentation conditions for Aspergillus sp.S125 and Muyocopron sp.A5 to evaluate the feasibility of large-scale mogroside V conversion.After optimization,Aspergillus sp.S125 converted 10 g/L of mogroside V into 4.5 g/L of mogroside II A and 3.6 g/L of aglycone after 3 days of fermentation,whereas Muyocopron sp.A5 selectively produced 4.88 g/L of siamenoside I from 7.5 g/L of mogroside V after 36 h of fermentation.This study not only identifies highly effective biocatalytic candidates for mogrosides transformation,but also strongly suggests the potential of plant endophytic fungi as valuable resources for the biocatalysis of natural compounds.展开更多
A key aspect of sustainable bioeconomy is the recirculation of renewable,agricultural waste streams as substrates for microbial production of high-value compounds.One approach is the bioconversion of corn stover,an ab...A key aspect of sustainable bioeconomy is the recirculation of renewable,agricultural waste streams as substrates for microbial production of high-value compounds.One approach is the bioconversion of corn stover,an abundant maize crop byproduct,using the fungal maize pathogen Ustilago maydis.U.maydis is already used as a unicellular biocatalyst in the production of several industrially-relevant compounds using plant biomass hydrolysates.In this study,we demonstrate that U.maydis can grow using untreated corn stover as its sole carbon source.We developed a small-scale bioreactor platform to investigate U.maydis processing of corn stover,combining online monitoring of fungal growth and metabolic activity profiles with biochemical analyses of the pre-and post-fermentation residues.Our results reveal that U.maydis primarily utilizes soluble sugars i.e.,glucose,sucrose and fructose present in corn stover,with only limited exploitation of the abundant lignocellulosic carbohydrates.Thus,we further explored the biotechnological potential of enhancing U.maydis´lignocellulosic utilization.Additive performance improvements of up to 120%were achieved when using a maize mutant with increased biomass digestibility,co-fermentation with a commercial cellulolytic enzyme cocktail,and exploiting engineered fungal strains expressing diverse lignocellulose-degrading enzymes.This work represents a key step towards scaling up the production of sustainable compounds from corn stover using U.maydis and provides a tool for the detailed monitoring of the fungal processing of plant biomass substrates.展开更多
基金supported by the Strategic Priority Research Program of the Chinese Academy of Sciences(XDC0110201)the National Natural Science Foundation of China(32222004 and 32070083)+3 种基金the Major Program and Innovation Fund of Haihe Laboratory of Synthetic Biology(22HHSWSS00003 and 22HHSWSS00017)the CAS Project for Young Scientists in Basic Research(YSBR-072)the Youth Innovation Promotion Association of Chinese Academy of Sciences(2021177)the Tianjin Synthetic Biotechnology Innovation Capacity Improvement Project(TSBICIP-KJGG-008).
文摘Background Formolase(FLS)is a computationally designed enzyme that catalyzes the carboligation of two or three C1 formaldehyde molecules into C2 glycolaldehyde or C3 dihydroxyacetone(DHA).FLS lays the foundation for several artificial carbon fixation and valorization pathways,such as the artificial starch anabolic pathway.However,the application of FLS is limited by its low catalytic activity and product promiscuity.Findings FLS,designed and engineered based on benzoylformate decarboxylase from Pseudomonas putida,was selected as a candidate for modification.To evaluate its catalytic activity,25 residues located within an 8Ådistance from the active center were screened using single-point saturation mutagenesis.A screening approach based on the color reaction of the DHA product was applied to identify the desired FLS variants.After screening approximately 5,000 variants(approximately 200 transformants per site),several amino acid sites that were not identified by directed evolution were found to improve DHA formation.The serine-to-phenylalanine substitution at position 236 improved the activity towards DHA formation by 7.6-fold.Molecular dynamics simulations suggested that the mutation increased local hydrophobicity at the active site,predisposing the cofactor-C2 intermediate to nucleophilic attack by the third formaldehyde molecule for subsequent DHA generation.Conclusions This study provides improved FLS variants and valuable information into the influence of residues adjacent to the active center affecting catalytic efficiency,which can guide the rational engineering or directed evolution of FLS to optimize its performance in artificial carbon fixation and valorization.
文摘Tamarind seeds are one of the waste crops that were usually given to pigs and the use of spontaneous bioconversion can increase digestibility. The research objective was to evaluate nutrient digestibility spontaneous bioconversion of tamarind seeds at Timor Local Pig. The study was conducted from May to July 2017 in the Laboratory of Animal Production and Reproduction of Kupang State Agricultural Polytechnic. The study used local male pigs grower phase of 3-4 months old aged and used a randomized block design with four treatments and five replications, namely R0 = ration without bioconversion spontaneous tamarind seeds, R1 = rations containing 10% bioconversion spontaneous tamarind seeds, R2 = ration containing 20% bioconversion spontaneous tamarind seeds, R3 = ration containing 30% bioconversion spontaneous tamarind seeds. The variables measured were dry matter digestibility, crude protein, crude fiber, and tannins. The results showed that spontaneous bioconversion of tamarind seeds affected significantly （p 〈 0.01） on dry matter digestibility, crude protein, ether extract, ash, and tannin digestibility but no effect （p 〉 0.05） on crude fiber digestibility. It was concluded that the use of tamarind seeds spontaneous bioconversion in livestock rations of local pigs Timor should be as much as 20%.
基金supported by the National Natural Science Foundation of China (91745114, 21802160)the National Key R&D Program of China (2016YFA0202800)+2 种基金Shanghai Sailing Program (18YF1425700)Shanghai Advanced Research Institute Innovation Research Program (Y756812ZZ1(172002),Y756803ZZ1(171003))the support from the Hundred Talents Program of the Chinese Academy of Sciences~~
文摘CO2 is not only the most important greenhouse gas but also an important resource of elemental carbon and oxygen.From the perspective of resource and energy strategy,the conversion of CO2 to chemicals driven by renewable energy is of significance,since it can not only reduce carbon emission by the utilization of CO2 as feedstock but also store low-grade renewable energy as high energy density chemical energy.Although studies on photoelectrocatalytic reduction of CO2 using renewable energy are increasing,artificial bioconversion of CO2 as an important novel pathway to synthesize chemicals has attracted more and more attention.By simulating the natural photosynthesis process of plants and microorganisms,the artificial bioconversion of CO2 can efficiently synthesize chemicals via a designed and constructed artificial photosynthesis system.This review focuses on the recent advancements in artificial bioreduction of CO2,including the key techniques,and artificial biosynthesis of compounds with different carbon numbers.On the basis of the aforementioned discussions,we present the prospects for further development of artificial bioconversion of CO2 to chemicals.
文摘This study was undertaken to screen the filamentous fungi isolated from its relevant habitats(wastewater, sewage sludge and sludge cake) for the bioconversion of domestic wastewater sludge. A total of 35 fungal strains were tested against wastewater sludge (total suspended solids, TSS 1%—5% w/w) to evaluate its potentiality for enhancing the biodegradability and dewaterability using liquid state bioconversion(LSB) process. The strains were divided into five groups i.e. Penicillium, Aspergillus, Trichoderma, Basidiomycete and Miscellaneous, respectively. The strains WWZP1003, SCahmA103, SCahmT105 and PC-9 among their respective groups of Penicillium, Aspergillus, Trichoderma and Basidiomycete played potential roles in terms of separation(formation of pellets/flocs/filaments), biodegradation(removal of COD) and filtration(filterability) of treated domestic wastewater sludge. The Miscellaneous group was not considered due to its unsatisfactory results as compared to the other groups. The pH value was also influenced by the microbial treatment during fermentation process. The filterability of treated sludge was improved by fungal treatment, and lowest filtration time was recorded for the strain WWZP1003 and SCahmA103 of Penicillium and Aspergillus groups respectively compared with other strains.
基金the National Natural Science Foundation of China (No. 29136130).
文摘Production of 6-aminopenicillanic acid (6-APA) by hydrolysis using penicillin acylase (PA) was studied as a model of an enzymatic emulsion liquid membrane (ELM) process. The loss of PA activity was examined for various membrane compositions (organic solvent, surfactant, carrier). The effects of some experimental variables on the stability of emulsion were investigated. It was found that the choice of organic solvent greatly affected the stability of the emulsion. Increasing the concentration of the carrier in the membrane phase increases the transfer rate of substrate and products but also has a destabilizing effect on the emulsion. The recovery of 6-APA obtained by a di-carrier system (N263-N1923) was much higher than those when either of the di-carriers was used separately. The whole process was controlled both by the enzymatic reaction rate and by the transfer rate of the substrate and the products, however, the ratio of them could be changed by varying the composition of the system. For an optimum condition, it was obtained that the recovery ratio of 6-APA was over 80% and the conversion of benzyl penicillin (PG) was up to 90% in the external phase after 30 minutes. Meanwhile, the breakage percentage of the emulsion was less than 2%.
文摘Parthenium hysterophorus is a globally recognized invasive alien weed that prominently colonizes grazing areas and cultivated lands causing adverse effect on crop production. Major allelochemicals released from parthenium include sesqueterpene lactones and phenolic acids. Among these the presence of caffeic, vanillic and ferulic acids is of industrial significance as they possess potent free radical scavenging and anticancer activities. This study reports for the first time, high total phenolic acid content (20.82 ± 0.82 mg GAE/g dry sample) in parthenium. The GC-MS analysis indicated the presence of ferulic, p-coumaric, vanillic and gallic acid as major phenolic components. Free radical scavenging activity of the phenolic acids extract gave an EC50 value 130.4 μg/ml when measured using DPPH assay. Anticancer activity of parthenium phenolic extract against A-498 (IC50 0.5237 μg/ml) and MDA-MB231 (IC50 and 0.2685 μg/ml) cancerous cell lines indicated its potential to be used as anticancer agent.
文摘Since 1993, China has become a net importer of energy from a net exporter. The total energy con- sumption has been greater than the total supply, and the external dependence of the energy demand increases rapidly. China＇ s crude oil import volume and imports amount reached 253.78 million tons and 196.664 billion US dollars in 2011, with a growth rate of 6 % and 45.3 %, respectively, year-on-year. The significant increase in demand for oil and the caused structural contradictions are increasingly becoming the greatest challenge for China＇ s energy security. The energy crisis has not only touched everyone＇ s nerves, but also sparked a strong desire to find alternative energy.
文摘Switchgrass (Panicum virgatum L.) is a native warm-season grass and it is one of potential bioenergy crops. The objectives of this study were to: 1) assess the best performing switchgrass genotype suitable for Kansas soil and climatic condition in the USA, 2) determine the correlation between plant height or tiller numbers per plant and dry biomass of various switchgrass genotypes, and 3) assess a bioconversion efficiency of certain varieties of switchgrass. Twenty-two different genotypes of seedlings were allowed to grow in cones for 30 days under controlled environments. The genotype Cave-in-Rock was the shortest among the genotypes. Significant difference in number of tillers per plant was observed among the genotypes. The genotypes Alamo recorded the highest numbers of tiller plant-1 and the genotype Cave-in-Rock had the lowest numbers of tiller plant-1 compared with other genotypes. The genotypes Alamo, NL 94 C2-2, NL 94 C2-3, NSL 2009-1 and NSL 2009-2 had increased above ground biomass compared with other genotypes. The correlation study indicates that there was a significant positive correlation between number of tillers per plant and per plant dry weight (R2 = 0.93), number of tillers per plant and plant height (R2 = 0.94), and plant height and per plant dry weight (R2 = 0.82). Based on the biomass composition, the SWG 2007-2 genotype was the promising switchgrass line for the bioconversion through the sugar platform route due to high carbohydrate and low lignin content. On the other hand, the high biomass yield per unit area of field in NL 94 C2-1 led this genotype with the highest total carbohydrate yield per unit area of field despite the lowest total carbohydrate content in the genotype. These results are pertinent for crop breeders to develop the most promising switchgrass line with high biomass yield and high bioconversion efficiency to produce biofuel through the sugar platform route.
文摘The bioconversion process of municipal solid waste was assessed on the basis of the results obtained from the biodrying reactor working at a full industrial scale.The bio-reactor is a part of mechanical-biological installation following mechanical stage.The bio-reactor was equipped with measuring devices allowing the analysis of the parameters like:temperature both inside the waste and also air above the waste and also the humidity of waste during the 14 days of the biodrying process.The kinetics of bioconversion was assessed basing on measured the loss of ignition(LOI)parameter detected during the biodrying process.The LOI value of the samples varied from 17.03%Am.to 30.34%d.m.depending on the location inside the reactor.The estimated kinetic rate constant kT of the bioconversion of biomass in the industrial reactor was kT=0.3141.In analyzed case study the calorific value of product leaving the full-scale bio-reactor is too low to use this product as an alternative fuel.As w'as stated the reason of this is too low a share of the carbon-rich fraction in the feedstock.
基金This research was supported by grants Programa de Fomento y Apoyo a Proyectos de Investigación(PRO-FAPI 2011,2012)Universidad Autónoma de Sinaloa and Fundación Produce Sinaloa,AC(2010,2011,2012).
文摘The main objective of this investigation was to study the time effect during solid state bioconversion (SSB) on total phenolics content (TPC) and antioxidant activity (AoxA) of common beans to improve antihypertensive functionality. Cooked cotyledons of dehulled common beans were inoculated with a suspension of R. oligosporus NRRL 2710 (1 × 106 spores/mL), and incubated at 35℃ for times of 24, 36, 48, 60, 72, 84, 96 and 108 h (after 108 h the cotyledons showed off odor). Flours from bioprocessed dehulled common bean from each incubation time were blended with their corresponding milled seed coats. The best time for producing bioprocessed common bean (added with seed coats) functional flour with the highest AoxA (ORAC value = 17,468 μmol Trolox equivalents (TE)/100 gsample, dw;ABTS value = 13,505 μmol TE/100 gsample, dw) was 108 h. The SSB process substantially increased TPC and total hydrophilic AoxA and antihypertensive potential of common beans in 2.24, 2.45 - 2.73 and 6769 times, respectively. Proteins hydrolyzates from unprocessed whole and bioprocessed (108 h) common beans had IC50 [concentration needed to inhibit 50% the activity of angiotensin converting enzyme (ACE)] of 79.2 and 0.0117 μg/mL, respectively. The SSB is an efective strategy to improve the TPC of common beans for enhanced functionality with improved antioxidant activity and antihypertensive potential.
基金supported by National Natural Science Foundation of China(42106144)Natural Science Foundation of Shandong Province(ZR2021QE125,ZR2020QD089 and ZR2023QC207)+2 种基金Science and Technology Project of Beijing Life Science Academy Company Limited(0002023CC0090)Natural Science Foundation of Qingdao City(23-2-1-52-zyyd-jch)Central Public-interest Scientific Institution Basal Research Fund(1610232023020).
文摘This study presented new insights into the sustainable conversion of total petroleum hydrocarbon(TPHC)into polyhydroxyalkanoates(PHAs)using wetland microbial fuel cells(WMFCs).The main innovations included the following two points:(1)The integration of bioelectricity generation with efficient PHA production further underscored the potential of electroactive biofilms as a sustainable platform for simultaneous TPHC biotransformation,bioelectricity recovery and PHA production.(2)The interactive dynamics of PHAs,metabolites,extracellular polymeric substances(EPS)and microorganisms during the formation and stabilization of electroactive biofilms provided novel insights into microbial strategies for carbon utilization.As the electroactive biofilm formed and stabilized,the current density enhanced significantly from 0 to 101 mA m2,then stabilized,and finally dropped to 3.51 mA m2.Similarly,the power density showed a trend of increasing in the initial stage,maintaining in the middle stage,and then descending in the later stage.The production of six types of PHAs was identified:poly(3-hydroxybutyrate)[P(3HB)],poly(3-hydroxyvalerate)[P(3HV)],poly(3-hydroxybutyrate-co-3-hydroxyvalerate)[P(3HB-co-3HV)],poly[(R)-3-hydroxybutyrate-co-(R)-3-hydroxyhexanoate][P(3HB-co-3HHX)],poly(3-hydroxyhexadecanoate)[P(3HHD)]and poly(3-hydroxyoctadecanoate)[P(3HOD)],highlighting the metabolic flexibility of electroactive biofilms.The total PHA content was initially undetectable(days 0–4),gradually increased(days 4–28),rose rapidly(days 28–48),gradually increased and descended(days 48–68).The maximum PHA content of 0.664 g g⁻1 DCW achieved highlighted the dual functionality of WMFCs in bioelectricity production and PHA biosynthesis,distinguishing it from conventional MFC applications.The TPHC biodegradation ratio demonstrated a gradual increase(days 0–28),with a more pronounced rise(days 28–48),and a gradual rise to 76.1%(days 48–68).Throughout the process,the metabolite volatile fatty acids(VFAs)produced were primarily acetate,propionate,butyrate and valerate.The trend of VFA production from days 0–56 closely followed that of TPHC biodegradation.The trend of tyrosine/tryptophan proteins in EPS was aligned with that of biofilm thickness.The strong correlation between the increase in the biofilm thickness and the intensity and peak height of tyrosine/tryptophan proteins during the first 20 days suggested that these proteins were integral to the structural integrity of the biofilms,and from days 20–64,the minimal variation in their intensity and peak height indicated that the biofilms had reached a relatively stable state.The biofilms in turn provided a stable microbial substrate and energetic support for the subsequent efficient synthesis of PHA.During the early phase,the dual-function bacteria,such as Pseudomonas,Bacillus,Acinetobacter and Desulfosarcina,prioritized electron transfer and bioelectricity production using available carbon sources.As bioelectricity generation became less critical in the later phase,the bacteria shifted to intracellular PHA accumulation,transitioning from bioelectricity production to PHA biosynthesis.Finally,a comprehensive network connecting functional microorganisms with bioelectricity production,PHA content,TPHC biodegradation,VFA production and EPS peak height was established.Overall,these findings provided valuable insights into the dynamic interactions and metabolic strategies of electroactive biofilms in WMFCs,highlighting their potential for the efficient bioconversion of PHCs into PHAs.
基金supported by the National Research Foundation of Korea(NRF)grant funded by the Korean government(MSIT)(No.NRF-2020R1A5A1019631).
文摘The study investigated the enhanced production of 2-hydroxybutyric acid(2-HBA)from threonine using a two-step whole-cell bioconversion by recombinant Escherichia coli BL21(DE3)overexpressing threonine dehydratase and keto-reductase.To address the rate-limiting step posed by NADH regeneration for the keto-reductase reaction converting 2-ketobutyric acid(2-KBA)to 2-HBA,formate dehydrogenase from Candida boidinii was overexpressed under the T7 promoter,resulting in a high titer of 1015 mM and a yield of 0.70 mol/mol.Furthermore,the yield was improved by disrupting three enzymes responsible for the degradation of the intermediate(2-KBA),pyruvate-formate lyase(PflB),pyruvate oxidase(PoxB),and pyruvate dehydrogenase complex(PDHc),leading to an impressive yield of 0.99 mol/mol,closely approaching the theo-retical maximum of 1.00 mol/mol.The triple mutant,designed to prevent 2-KBA degradation,achieved a remarkable titer of 1,400 mM and volumetric productivity of 58 mmol/L/h.To the best of our knowledge,this achievement represents the highest reported titer and yield for 2-HBA production to date.
基金This work was supported by the DGAPA-UNAM(PAPIIT project,No.IN102721)the support from CONAHCYT through the Investigadoras e Investigadores por Mexico program(Researcher ID 6407,Project 265).
文摘Anaerobic oxidation of methane(AOM)can contribute to reducing methane emissions in landfills;however,the AOM rates vary depending on the inoculum source.This study addressed the capacity of AOM of a fermentative microbial community derived from a reactor treatingmunicipal solidwastes.First,the inoculum’s autotrophic capacitywas verified using a gasmixture of 75% CO_(2) and 25% H_(2).Results demonstrated that the fermentative microbial community reached amaximum CO_(2) consumption rate of 22.5±1.2 g CO_(2)/(m^(3)·h),obtaining acetate as the main product.Then,the inoculum was grown on a gas mixture of 50%CH_(4),35%CO_(2),and 15%N_(2),using iron(Fe^(3+))as the electron acceptor.The AOM rates increased over time and peaked at 3.1±0.9 g CH_(4)/(m^(3)·h)by 456 h with the simultaneous consumption of CO_(2).Acetate was the main product,with amaximum concentration of 180±9mg/L.By 408 h,a bacterial cluster of indicator species correlated with the AOM rates,including to Rhodobactereceae(r=0.80),Oceanicola(r=0.80),Propionicicella(r=0.77),Christensenellaceae(r=0.58),Oscillospiraceae(r=0.53),Mobilitalea(r=0.66),Hungateiclostridiaceae(r=0.46),and Izemoplasmatales(r=0.77).Methanosarcina,Methanobacterium,and Methanoculleus correlated with the AOM and CO_(2) consumption rates.A co-occurrence network analysis showed that Methanosarcina positively interacted with syntrophic bacteria like Christensenellaceae and Acinetobacter and diverse heterotrophic bacteria.This study demonstrated the feasibility of obtaining a CH_(4)-oxidizing microbial community in 16 days,exhibiting AOM rates higher than those reported for soils.
基金supported by the National Natural Science Foundation of China, Grant Nos. 22108205 and 21978219the Scientific Research Program of Tianjin Education Commission, Grant No. 2019KJ237。
文摘Nanocellulose has various outstanding properties and great potential for replacing petrochemical products.The utilization of lignocellulose to produce nanocellulose is of great significance to the sustainable development of the economy and society.However,the direct extraction of nanocellulose from lignocellulose by chemical method is challenged by toxic chemicals utilization,energy and time consumption,and waste water generation.Therefore,this paper addressed the conversion of lignocellulosic biomass into bacterial nanocellulose(BNC)by the biological method.Moreover,this article highlights the recent advances in potentials and challenges of lignocellulosic biomass for BNC production through the bioconversion process,including biomass pretreatment,enzymatic hydrolysis,glucose and xylose fermentation,GA accumulation,and inhibitor tolerant.The development in metabolic and evolutionary engineering to enhance the production capacity of BNC-producing strain is also discussed.It is expected to provide guidance on the effective bioproduction of nanocellulose from lignocellulosic biomass.
基金supported by the Zhejiang Provincial Natural Science Foundation of China(No.LY19B060008)the Zhejiang Provincial Key Research Program of China(Grant 2019C02088).
文摘Tetrahydrocurcumin(THCu)is one of the major reduction metabolites of curcumin(CUR),which is a well-known yellow food pigment from turmeric with strong antioxidant,anti-inflammatory,and antibacterial properties.THCu exhibits better solubility,stability,bioavailability than CUR and similar pharmacological activities.In recent years,the market demand for the colorless THCu has a large growth for its application in the field of functional foods and cosmetics due to its strong antioxidant and skin-whitening function.Current industrial production mainly relies on chemical synthesis.The environmental-friendly and good-selectivity synthesis methods like microbial/enzymatic transformation might be better alternative.Several microorganisms have been reported with the capability of CUR reduction.Good-selectivity enzymes also have been characterized like alcohol dehydrogenase from equine liver and curcumin reductase from gut bacteria.This review focuses on the production technology of THCu and summarizes researches on its new chemical synthesis strategies,possible bioconversion methods,detection methods and potential applications.
基金supported by the National Key Research and Development Program of China(Grant No.2018YFA0900304-300)the Natural Science Foundation of Jiangsu Province(Grant Nos.BK20160053 and BE2018055)the Priority Academic Program Development of Jiangsu Higher Education Institutions,111 Project(Grant No.111-2-06).
文摘A cholesterol oxidase(COD)was hybridized with Ca^(2+),Zn^(2+),Al^(3+),Fe^(2+) and Mn^(2+).After precipitation with PO_(4)^(3-) at 4℃ for 72 h,the resulting pellets were freeze-dried.In scanning electron microscopy assays,the metal-COD complexes revealed flower-like or granular structures after hybridization.Fourier transform infrared spectroscopy assay revealed the characteristic peaks of both the enzyme and metal materials.X-ray diffraction analysis indicated that COD was encapsulated in CaHPO_(4)·2H_(2)O-,Zn_(3)(PO_(4))_(2)·4H_(2)O-,AlPO_(4-),FeP_(4-) and Mn_(3)(PO_(4))_(2)·3H_(2)O-based nanostructures,respectively.Differential scanning calorimetry assay indicated significant increases in thermo-denaturation temperatures from 60.5℃ to 167.02℃,167.02℃,137.70℃,172.85℃ and 160.99℃,respectively.Using steroid derivatives as substrates,this enzyme could convert cholesterol,pregnenolone,dehydroepiandrosterone,ergosterol,b-sitosterol and stigmasterol to related single products.Hybridization in metal-based nanostructures could significantly enhance the initial conversion ratio and reaction stability of the enzyme.In addition,substrate selectivity could be affected by various metal materials.Briefly,using Ca^(2+),Zn^(2+),Al^(3+),Fe^(2+) and Mn^(2+) as hybrid raw materials could help to encapsulate COD in related metal-enzyme nanostructures,and could help to promote the stability and tolerant properties of the enzyme,while also enhancing its catalytic characteristics.
基金supported by Basilicata Region within the framework of"Programma di Sviluppo Rurale 2014-2020"(project"FeedInsect"—measure 16.2,D.D.424/2019)and PO FESR Basilicata 2014-2020—Action 1B.1.2.2(project"Valbioeconomia,"D.D.660/2021).
文摘Bioconversion is a biological process by which organic materials are converted into products with higher biological and commercial value.During its larval stage the black soldier fly Hermetia illucens is extremely voracious and can feed on a wide vari-ety of organic materials.To study the impact of different fruit byproducts on the insect's growth,final larval biomass,substrate reduction,bioconversion parameters,and larval nu-tritional composition,10000 black soldier fly larvae(BSFL)were reared on 7.0 kg of one of three substrates(strawberry,tangerine,or orange)or on a standard diet as a control.The results highlight that BSFL can successfully feed and grow on each of these diets,though their development time,growth rate,and final biomass were differently impacted by the substrates,with strawberry being the most suitable.The lipid and protein contents of BSFL were similar among larvae fed on different substrates;however,major differences were detected in ash,micronutrient,fiber,fatty acid,and amino acid contents.Overall,the results indicate that fruit waste management through the BSFL bioconversion process rep-resents a commercially promising resource for regional and national agrifood companies.Our study offers new perspectives for sustainable and environmentally friendly industrial development by which fruit byproducts or waste might be disposed of or unconventionally enhanced to create secondary products of high biological and economic value,including BSFL biomass as animal feed or,in perspective,as alternative protein source for human nutrition.
基金US Department of Energy,award number DE-FE0026161The authors would also like to thank Dr.Yanna Liang and Ji Zhang for providing the optimized microbial media for bioconversion.
文摘Biogenic coalbed methane(BCBM)reservoirs aim to produce methane from in situ coal deposits following microbial conversion of coal.Success of BCBM reservoirs requires economic methane production within an acceptable timeframe.The work reported here quantifies the findings of previously published qualitative work,where it was found that bioconversion induces strains in the pore,matrix and bulk scales.Using imaging and dynamic strain monitoring techniques,the bioconversion induced strain is quantified here.To understand the effect of these strains from a reservoir geomechanics perspective,a corresponding poromechanical model is developed.Furthermore,findings of imaging experiments are validated using core-flooding flow experiments.Finally,expected field-scale behavior of the permeability response of a BCBM operation is modeled and analyzed.The results of the study indicated that,for Illinois coals,bioconversion induced strains result in a decrease in fracture porosity,resulting in a detrimental permeability drop in excess of 60%during bioconversion,which festers itself exponentially throughout its producing life.Results indicate that reservoirs with high initial permeability that will support higher Darcian flowrates,would be better suited for coal bioconversion,thereby providing a site-selection criteria for BCBM operations.
基金supported by the National Key R&D Program of China(2021YFC2101303)by the Natural Science Foundation of Jiangxi Province of China(20212BAB215006,20224BAB215023,20232BAB205008)by the Foundation of Jiangxi Educational Committee(GJJ2201346,GJJ2201319).
文摘Fungal endophytes,as an untapped resource of glycoside hydrolase biocatalysts,need to be further developed.Mogroside V,the primary active compound in Siraitia grosvenorii fruit,can be converted into other various bioactive mogrosides by selective hydrolysis of glucose residues at C3 and C24 positions.In present study,20 fungal strains were randomly selected from our endophytic fungal strain library to assess their capability for mogroside V transformation.The results revealed that relatively high rate(30%)endophytic fungal strains exhibited transformative potential.Further analysis indicated that endophytic fungi could produce abundant mogrosides,and the pathways for biotransforming mogroside V showed diverse.Among the given fungal endophytes,Aspergillus sp.S125 almost completely converted mogroside V into the end-products mogroside II A and aglycone within just 2 days of fermentation;Muyocopron sp.A5 produced rich intermediate products,including siamenoside I,and the end-product mogroside II E.Subsequently,we optimized the fermentation conditions for Aspergillus sp.S125 and Muyocopron sp.A5 to evaluate the feasibility of large-scale mogroside V conversion.After optimization,Aspergillus sp.S125 converted 10 g/L of mogroside V into 4.5 g/L of mogroside II A and 3.6 g/L of aglycone after 3 days of fermentation,whereas Muyocopron sp.A5 selectively produced 4.88 g/L of siamenoside I from 7.5 g/L of mogroside V after 36 h of fermentation.This study not only identifies highly effective biocatalytic candidates for mogrosides transformation,but also strongly suggests the potential of plant endophytic fungi as valuable resources for the biocatalysis of natural compounds.
基金Open Access funding enabled and organized by Projekt DEALfunded by the NRW Strategic Project Bioeconomy Science Center(BioSC),Boost Fund 2.0(“NextVegOil”2021_04)+1 种基金The scientific activities of the BioSC were financially supported by the Ministry of Culture and Science within the framework of the NRW Strategieprojekt BioSC(No.313/323-400-00213)Additional funding was provided by Germany’s Federal Ministry of Education and Research(BMBF)grant“Cornwall,”031B1303A and Deutsche Forschun-gsgemeinschaft(DFG,German Research Foundation)under Germany’s Excel-lence Strategy-EXC 2048/1-Project ID:390686111 to M.Pa.,and Marie Curie PIOF-GA-2013-623553 to V.R.
文摘A key aspect of sustainable bioeconomy is the recirculation of renewable,agricultural waste streams as substrates for microbial production of high-value compounds.One approach is the bioconversion of corn stover,an abundant maize crop byproduct,using the fungal maize pathogen Ustilago maydis.U.maydis is already used as a unicellular biocatalyst in the production of several industrially-relevant compounds using plant biomass hydrolysates.In this study,we demonstrate that U.maydis can grow using untreated corn stover as its sole carbon source.We developed a small-scale bioreactor platform to investigate U.maydis processing of corn stover,combining online monitoring of fungal growth and metabolic activity profiles with biochemical analyses of the pre-and post-fermentation residues.Our results reveal that U.maydis primarily utilizes soluble sugars i.e.,glucose,sucrose and fructose present in corn stover,with only limited exploitation of the abundant lignocellulosic carbohydrates.Thus,we further explored the biotechnological potential of enhancing U.maydis´lignocellulosic utilization.Additive performance improvements of up to 120%were achieved when using a maize mutant with increased biomass digestibility,co-fermentation with a commercial cellulolytic enzyme cocktail,and exploiting engineered fungal strains expressing diverse lignocellulose-degrading enzymes.This work represents a key step towards scaling up the production of sustainable compounds from corn stover using U.maydis and provides a tool for the detailed monitoring of the fungal processing of plant biomass substrates.
