High ammonia-nitrogen digestate has become a key bottleneck limiting the anaerobic digestion of organic solid waste.Vacuum ammonia stripping can simultaneously remove and recover ammonia nitrogen,which has attracted a...High ammonia-nitrogen digestate has become a key bottleneck limiting the anaerobic digestion of organic solid waste.Vacuum ammonia stripping can simultaneously remove and recover ammonia nitrogen,which has attracted a lot of attention in recent years.To investigate the parameter effects on the efficiency and mass transfer,five combination conditions(53℃ 15 kPa,60°C 20 kPa,65°C 25 kPa,72°C 35 kPa,and 81°C 50 kPa)were conducted for ammonia stripping of sludge digestate.The results showed that 80%of ammonia nitrogen was stripped in 45 min for all experimental groups,but the ammonia transfer coefficient varied under different conditions,which increased with the rising of boiling point temperature,and reached the maximum value(39.0 mm/hr)at 81°C 50 kPa.The ammonia nitrogen removal efficiency was more than 80%for 30 min vacuum stripping after adjusting the initial pH to above 9.5,and adjustment of the initial alkalinity also affects the pH value of liquid digestate.It was found that pH and alkalinity are the key factors influencing the ammonia nitrogen dissociation and removal efficiency,while temperature and vacuum mainly affect the ammonia nitrogen mass transfer and removal velocity.In terms of the mechanism of vacuum ammonia stripping,it underwent alkalinity destruction,pH enhancement,ammonia nitrogen dissociation,and free ammonia removal.In this study,two-stage experiments of alkalinity destruction and ammonia removal were also carried out,which showed that the two-stage configuration was beneficial for ammonia removal.It provides a theoretical basis and practical technology for the vacuum ammonia stripping from liquid digestate of organic solid waste.展开更多
The integration of sustainable technologies in waste management systems has become imperative in addressing the escalating challenges of agricultural productivity and sustainability. Plugs are essential when starting ...The integration of sustainable technologies in waste management systems has become imperative in addressing the escalating challenges of agricultural productivity and sustainability. Plugs are essential when starting crop production in controlled environment agriculture (CEA) setups and greenhouses. Horticultural crops such as vegetables, fruiting, and ornamental plants that utilize plugs have demonstrated higher success rates, healthier plants, and higher total yields. The APS Laboratory for Sustainable Agriculture explored the innovative utilization of digestate from the Home Water-Energy-Food Systems (H-WEF). The H-WEF system converts household food waste into biogas, electricity, and nutrient-rich digestate. The digestate from the H-WEF system was used to produce agricultural plugs, presenting a novel approach to circular resource utilization. We carried out the growth of Rex Butterhead Lettuce Latuca sativa plugs with 1) control system (synthetic fertilizer) and seven different treatments, 2) 5% Digestate—95% RO Water (5D–95RO);3) 10% Digestate—90% RO Water (10D–90RO);4) 15% Digestate—85% RO Water (15D–85RO);5) 20% Digestate—80% RO Water (20D–80RO);6) 25% Digestate—75% RO Water (25D–75RO);7) 30% Digestate—70% RO Water (30D–70RO);8) 35% Digestate—65% RO Water (35D–65RO). The plugs were cultivated for 15 days in a controlled environment until two leaves had developed after the cotyledon. After 15 days, we collected data on wet weight (g), plug head area (cm2), total leaf area (cm2), total chlorophyll content (mg/cm2), and dry weight (g). In addition, we collected data on the Leaf Area Index (LAI, cm2/cm2) and Specific Leaf Area (SLA, cm2/g). The synthetic fertigation yielded a higher wet weight than the following treatments: 5D–95RO, 10D–90RO, and 35D–65RO. While the 30D–70RO treatment produced a larger plug head than all other treatments. The digestate-based fertilizers were comparable to the synthetic fertilizer at dilutions of 25D–75RO and 30D–70RO. This study underscores the viability of using digestate for plug production, providing crucial insights for growers navigating the challenges of sustainable agricultural practices.展开更多
The paper presents the results of a two-year research of properties and the way of use of briquettes and pellets made of separated and partially dehydrated digestate from agricultural BGSs (biogas stations). Digesta...The paper presents the results of a two-year research of properties and the way of use of briquettes and pellets made of separated and partially dehydrated digestate from agricultural BGSs (biogas stations). Digestate is a by-product of BGS. There are approximately 170 agricultural BGSs operating in the Czech Republic. Unprocessed digestate with the dry mass content around 6% is usually applied to soil as a lighter mineral fertilizer. If digestate is separated and the separated solid component of the digestate is further dehydrated to 14 % moisture, it can be processed by pressing to the form of very solid pellets and briquettes, also with various additives. It was also ascertained that mechanical strength and shape of briquettes does not change due to long-term storage. In this form, the compressed digestate can be used in various ways. One of the ways is its energetic use by direct burning. That is why we have observed its calorific value and combustion heat. Another alternative use of compressed digestate from BGS is its application in targeted treatment of in particular mechanical properties of soil and its water regime. The briquettes and pellets have great water sorption properties--the briquette retains water and as a consequence grows up to four times in size. This specific property was analysed and it was ascertained that the speed of water sorption depends on the composition of the compressed mixture (i.e., the type of material and the size of its particles), but also on the total weight of the produced briquettes (i.e., their size). Similar dependency was ascertained for other briquette materials that were analysed.展开更多
The importance of enhancing sludge dewaterability is increasing due to the considerable impact of excess sludge volume on disposal costs and on overall sludge management. This study presents an innovative approach to ...The importance of enhancing sludge dewaterability is increasing due to the considerable impact of excess sludge volume on disposal costs and on overall sludge management. This study presents an innovative approach to enhance dewaterability of anaerobic digestate(AD) harvested from a wastewater treatment plant. The combination of zero valent iron(ZVI, 0–4.0 g/g total solids(TS)) and hydrogen peroxide(HP, 0–90 mg/g TS) under pH 3.0 significantly enhanced the AD dewaterability. The largest enhancement of AD dewaterability was achieved at 18 mg HP/g TS and 2.0 g ZVI/g TS, with the capillary suction time reduced by up to 90%. Economic analysis suggested that the proposed HP and ZVI treatment has more economic benefits in comparison with the classical Fenton reaction process. The destruction of extracellular polymeric substances and cells as well as the decrease of particle size were supposed to contribute to the enhanced AD dewaterability by HP + ZVI conditioning.展开更多
The inhibition of nitrification by mixing nitrification inhibitors(NI)with fertilizers is emerging as an effective method to reduce fertilizer-induced nitrous oxide(N_(2)O)emissions.The additive 3,4-dimethylpyrazole p...The inhibition of nitrification by mixing nitrification inhibitors(NI)with fertilizers is emerging as an effective method to reduce fertilizer-induced nitrous oxide(N_(2)O)emissions.The additive 3,4-dimethylpyrazole phosphate(DMPP)apparently inhibits ammonia oxidizing bacteria(AOB)more than ammonia oxidizing archaea(AOA),which dominate the nitrification in alkaline and acid soil,respectively.However,the efficacy of DMPP in terms of nitrogen sources interacting with soil properties remains unclear.We therefore conducted a microcosm experiment using three typical Chinese agricultural soils with contrasting pH values(fluvo-aquic soil,black soil and red soil),which were fertilized with either digestate or urea in conjunction with a range of DMPP concentrations.In the alkaline fluvo-aquic soil,fertilization with either urea or digestate induced a peak in N_(2)O emission(60μg N kg^(-1)d^(-1))coinciding with the rapid nitrification within 3 d following fertilization.DMPP almost eliminated this peak in N_(2)O emission,reducing it by nearly 90%,despite the fact that the nitrification rate was only reduced by 50%.In the acid black soil,only the digestate induced an N_(2)O emission that increased gradually,reaching its maximum(20μg N kg^(-1)d^(-1))after 5–7 d.The nitrification rate and N_(2)O emission were both marginally reduced by DMPP in the black soil,and the N_(2)O yield(N_(2)O-N per NO2–+NO3–-N produced)was exceptionally high at 3.5%,suggesting that the digestate induced heterotrophic denitrification.In the acid red soil,the N_(2)O emission spiked in the digestate and urea treatments at 50 and 10μg N kg^(-1)d^(-1),respectively,and DMPP reduced the rates substantially by nearly 70%.Compared with 0.5%DMPP,the higher concentrations of DMPP(1.0 to 1.5%)did not exert a significantly(P<0.05)better inhibition effect on the N_(2)O emissions in these soils(either with digestate or urea).This study highlights the importance of matching the nitrogen sources,soil properties and NIs to achieve a high efficiency of N_(2)O emission reduction.展开更多
Catalytic pyrolysis of digestate to produce aromatic hydrocarbons can be combined with anaerobic fermentation to effectively transform and utilize all biomass components,which can achieve the meaningful purpose of tra...Catalytic pyrolysis of digestate to produce aromatic hydrocarbons can be combined with anaerobic fermentation to effectively transform and utilize all biomass components,which can achieve the meaningful purpose of transforming waste into high-value products.This study explored whether catalytic pyrolysis of digestate is feasible to prepare aromatic hydrocarbons by analyzing the thermogravimetric characteristics,pyrolysis characteristics,and catalytic pyrolysis characteristics of digestate.For digestate pyrolysis,an increase in temperature was found to elevate the CO,CH_4,and monocyclic aromatic hydrocarbon(benzene,toluene,and xylene;BTX)content,whereas it decreased the contents of phenols,acids,aldehydes,and other oxygenates.Furthermore,the catalytic pyrolysis process effectively inhibited the acids,phenols,and furans in the liquid,whereas the yield of BTX increased from 25.45%to 45.99%,and the selectivity of xylene was also increased from 10.32%to 28.72%after adding ZSM-5.ZSM-5 also inhibited the production of nitrogenous compounds.展开更多
The development of methods for the efficient treatment and application of food waste digestate is an important research goal.Vermicomposting via housefly larvae is an efficient way to reduce food waste and achieve its...The development of methods for the efficient treatment and application of food waste digestate is an important research goal.Vermicomposting via housefly larvae is an efficient way to reduce food waste and achieve its valorization,however,studies on the application and performance of digestate in vermicomposting are rarely.The present study aimed to investigate the feasibility of the co-treatment of food waste and digestate as an additive via larvae.Restaurant food waste(RFW)and household food waste(HFW)were selected to assess the effects of waste type on vermicomposting performance and larval quality.Waste reduction rates of 50.9%–57.8%were observed in the vermicomposting of food waste mixed with digestate at a ratio of 25%,which were slightly lower than those for treatments without the addition of digestate(62.8%–65.9%).The addition of digestate increased the germination index,with a maximum value of 82%in the RFW treatments with 25%digestate,and decreased the respiration activity,with a minimum value of 30 mg-O_(2)/g-TS.The larval productivity of 13.9%in the RFW treatment system with a digestate rate of 25%was lower that without digestate(19.5%).Materials balance shows that larval biomass and metabolic equivalent had decreasing trends as the amount of digestate increased and HFW vermicomposting exhibited lower bioconversion efficiency than that of RFW treatment system regardless of the addition of digestate.These results suggest that mixing digestate at a low ratio(25%)during vermicomposting of foodwaste especially RFW could lead to considerable larval biomass and generate relatively stable residues.展开更多
A vacuum membrane distillation(VMD)process with permeate fractional condensation on membrane downstream has been developed for simultaneous recovery of phosphorus and nitrogen from liquid digestate.The polytetrafluoro...A vacuum membrane distillation(VMD)process with permeate fractional condensation on membrane downstream has been developed for simultaneous recovery of phosphorus and nitrogen from liquid digestate.The polytetrafluoroethylene(PTFE)membrane flux could reach 6000 g·m-2·h-1 with the rejection efficiency of total phosphorus(TP)over 0.99,under the condition of flowrate being 120 L·h-1 and temperature being 40°C.Membrane fouling occurred with a film of organics and microorganism deposited on the surface of the membrane.Membrane flux could be reversed after the membrane was rinsed by water.Higher feed temperature and flowrate could improve the membrane flux,while hardly affect the rejection efficiency of total phosphorus.The concentration of TP could reach 1600 mg·L-1 after membrane distillation,which is about 5 times of that in initial liquid digestate.On the downstream of the membrane,some of the permeate vapor was condensed under the vacuum condition and most of water was collected here.The remaining vapor enriched with total nitrogen(TN)was compressed and pumped to the atmospheric condition to condense.The TN concentration in atmospheric condensate was as high as 7000 mg·L-1 with the process separation factor for ammonia being enhanced to 114.展开更多
This study focused on the characterization of digestates resulting from anaerobic digestion of manioc effluents from attiéké factories. Two types of digestate were characterized, one consisting of manioc eff...This study focused on the characterization of digestates resulting from anaerobic digestion of manioc effluents from attiéké factories. Two types of digestate were characterized, one consisting of manioc effluent + urine and another composed of manioc effluent + urine + cow dung. As a result, these residues of bio-digestion rich in nutrients (NPK) can be used as agricultural fertilizer. Moreover, the determination of some microorganisms and heavy metals digestates allowed to better appreciate its fertilizing quality. These parameters remained in accordance with the quality standards of a digestate prescribed. These results show that digestates from anaerobic co-digestion of manioc effluents, urine and cow dung can be used without fear as an agricultural biofertilizer.展开更多
Anaerobic digestion of biomasses originates different products, the most abundant of which are methane and carbon dioxide. During this process, a 60-70% organic matter reduction occurs and the final product, the diges...Anaerobic digestion of biomasses originates different products, the most abundant of which are methane and carbon dioxide. During this process, a 60-70% organic matter reduction occurs and the final product, the digestate, is charac- terized by high biological stability and high contents of recalcitrant organic molecules and nutrients. In the present work digestates obtained by different mixture of biomasses in a full-scale co-digestion plant operating in Italy were characterized as whole samples without any pre-treatment or extraction by means of Fourier transform infrared spec- troscopy and fluorescence spectroscopy in the synchronous-scan mode and results were compared to those obtained on the single fresh substrates. Biomasses considered were: beef cattle slurry, maize or sorghum silage, agro-industrial residues, olive residues and olive mill wastewater. These substrates exhibited typical spectra related to their different chemical composition. Results obtained on digestates provided evidence of distinctive characteristic of the final product as a function of the different composition of the biomasses loaded into the digestion plant. We concluded that FTIR and fluorescence spectra of digestates produced in a real co-digestion plant “inherit” the main spectroscopic features of the organic wastes from which they are produced. Spectroscopic techniques used in this work succeeded in qualitatively characterizing and differentiating digestates obtained from biomasses of different chemical composition.展开更多
The possibility of producing biogas and methane from two phases olive pomace was considered using anaerobic digestion and the microbial characteristic of digestate for the agrarian use was analyzed. In the work, the m...The possibility of producing biogas and methane from two phases olive pomace was considered using anaerobic digestion and the microbial characteristic of digestate for the agrarian use was analyzed. In the work, the main aim was to obtain biogas, made from at least 50% methane, and a digestate that can be used in the field of agronomy, from the anaerobic digestion of the substrates. The tests were carried out by digesting different mixtures of the two-phase pomace, mulberry leaves and mud civil wastewater (pre-digested) in a batch system and in anaerobic mesophilic conditions (35 ~C). The substrates were properly homogenized in order to obtain mixtures of known and uniform composition. The initial and final STi (Total Solids) and initial SVi (Volatile Solids), the concentration of chemical oxygen demand and total phenols were measured and the process yield (m3/t SV) was quantified with standard procedure. The objectives of the study were the analysis of microbial biodiversity developed during fermentation of mixtures based products and the microbial communities corresponding to Eubacteria, Archaea and Fungiwas analyzed. The suitability of the digestate for agronomical use was evaluated by estimating pathogens bacteria that may be present and by index of inhibition of plant organisms model.展开更多
To improve anaerobic digestion(AD)efficiency of rice straw,solid alkaline CaO and the liquid fraction of digestate(LFD)were used as pretreatment agents of rice straw.The results showed that AD performance of rice stra...To improve anaerobic digestion(AD)efficiency of rice straw,solid alkaline CaO and the liquid fraction of digestate(LFD)were used as pretreatment agents of rice straw.The results showed that AD performance of rice straw with CaOLFD pretreatment was optimal in different pretreatment methods of the CaO+LFD,CaOLFD,LFD+CaO,CaO,and LFD.The maximum methane yield(314 ml(g VS)^(-1))and the highest VFAs concentration(14851 mg·L^(-1) on day 3)of the CaOLFD pretreatment group were 81%and 118%higher than that of the control group,respectively.Under the action of solid alkaline CaO,the bacteria of Clostridium,Atopostipes,Sphaerochaeta,Tissierella,Thiopseudomonas,Rikenellaceae,and Sedimentibacter could build up co-cultures with the archaeal of Methanosaeta,Methanobacterium,and Methanosarcina performing direct interspecies electron transfer(DIET)and improving AD performance of rice straw.Therefore,the combined pretreatment using CaO and LFD could not only pretreat rice straw but also stimulate co-cultures of microorganism to establish DIET enhancing AD efficiency.展开更多
Anaerobic digestion is a process that is widely used for the treatment of organic wastes. The digestate can be used as a soil amendment or crop fertiliser. The aims of our work were to evaluate 1) the physicochemical ...Anaerobic digestion is a process that is widely used for the treatment of organic wastes. The digestate can be used as a soil amendment or crop fertiliser. The aims of our work were to evaluate 1) the physicochemical composition and pathogen content in a digestate from poultry manure, according to international regulations, and 2) the effect of its soil application on the major chemical and biological soil properties and on the growth of Lactuca sativa. The experiment consisted of two groups of pots(with and without crop). Treatments applied to each group were as follows: low and high doses of digestate and inorganic fertiliser, and no application(control)(low dose: 70 kg nitrogen(N) ha^(-1) and 21 kg phosphorus(P) ha^(-1); high dose: 210 kg N ha^(-1) and 63 kg P ha^(-1)). Soil samples were taken 7 and 34 d(harvest) after treatment applications. Heavy metal and pathogen contents in the digestate were below the upper limit values. Despite the high pH and electrical conductivity values of the digestate, both soil parameters presented acceptable values for crop growth. Although there were no initial increases in total inorganic N and available P in soil with digestate application, an increase in the fresh weight of crop was observed with the high dose application. This is probably associated with the slow nutrient release from the digestate during the development of the crop. Changes in the microbial community were temporary and occurred at the initial sampling stage of the experiment.展开更多
This study investigated the effect of the digestate application depth on soil nitrogen volatilization and vertical distribution in black loam soil and sandy loam column.The contents of soil moisture,TKN(total Kjeldahl...This study investigated the effect of the digestate application depth on soil nitrogen volatilization and vertical distribution in black loam soil and sandy loam column.The contents of soil moisture,TKN(total Kjeldahl nitrogen),ammonium nitrogen,nitrate nitrogen,and the extent of ammonia volatilization were tested by applying digestate at depths of 0 cm,2 cm,6 cm,10 cm,15 cm and 20 cm,respectively.The experimental results showed that ammonia volatilization mainly occurred in the first 10 days and reduced significantly when the application depth was deeper than 10 cm.At the same application depth,compared with the black loam,the nitrogen loss in sandy loam through ammonia volatilization was less,and the penetration depth of nitrate nitrogen and ammonium nitrogen were all deeper.In the same soil,nitrate nitrogen penetrated deeper than ammonium nitrogen at all application depths.展开更多
To investigate the in vitro digestion and fermentation properties of soybean oligosaccharides(SBOS)extracted from defatted soybean meal,the changes in monosaccharide composition and molecular mass were analyzed.Subseq...To investigate the in vitro digestion and fermentation properties of soybean oligosaccharides(SBOS)extracted from defatted soybean meal,the changes in monosaccharide composition and molecular mass were analyzed.Subsequently,the effect of SBOS on microbial community structure and metabolites was studied by 16S rRNA gene sequencing and untargeted metabolomics based on liquid chromatography-mass spectrometry.Results showed that SBOS was not easily enzymolyzed during simulated digestion and could reach the large intestine through the digestive system.The significant decrease in the molecular mass of SBOS after in vitro fermentation indicated its utilization by the gut microbiota,which increased the contents of short-chain fatty acids and lactic acid,thereby reducing the pH of the fermentation broth.Moreover,the core community was found to consist of Blautia,Lactobacillaceae,and Pediococcus.SBOS up-regulated beneficial differential metabolites such as myo-inositol,lactose,and glucose,which were closely related to galactose,amino sugar,and nucleotide sugar metabolism.This study will provide a reference for exploring the relationship between the gut microbiota and the metabolites of SBOS,and provide a basis for the development and application of SBOS as an ingredient for functional products.展开更多
The formation of humic-like acids(HLAs)is an essential process for converting liquid digestate into organic soil amendments to enhance agricultural sustainability.The aim of this study was to investigate the impact of...The formation of humic-like acids(HLAs)is an essential process for converting liquid digestate into organic soil amendments to enhance agricultural sustainability.The aim of this study was to investigate the impact of oxygen and/or MnO_(2)on the production of HLAs.Herein,abiotic humification performance of the digestate dissolved organic matter(DOM)is investigated with fluxes of air and N2 in the absence and presence of MnO_(2).Our results demonstrated that the fate of digestate DOM greatly depends on the oxidizing environment,the MnO_(2)enhanced nitrogen involved in the formation of HLAs.The synergistic effects of MnO_(2)and oxygen effectively improved the production of HLAs,and the corresponding component evolution was analyzed using spectroscopic evidence.The twodimensional correlation spectroscopy results demonstrated that the reaction sequence of digestate DOM followed the order of protein-like substances,substances with an absorbance at 325 nm,substances with UV absorbance at 254 nm and HLAs.Additionally,excitation emission matrix fluorescence combined with parallel factor analysis(EEM-PARAFAC)showed that tryptophan-like C3 was more prone to transformation than tyrosine-like C2 and was responsible for the humification process.The substance with an absorbance at 325 nm was a reaction intermediate in the transformation process of protein-like substances to HLAs.The above findings can be used to promote the production of liquid fertilizer associated with carbon sequestration as well as the sustainable development of biogas production.展开更多
Hydrogen sulfide(H_(2)S)removal has been a significant concern in various industries.In this study,food waste diges-tate-derived biochar(DFW-BC),a by-product of food waste treatment with abundant minerals,was assessed...Hydrogen sulfide(H_(2)S)removal has been a significant concern in various industries.In this study,food waste diges-tate-derived biochar(DFW-BC),a by-product of food waste treatment with abundant minerals,was assessed for removing H_(2)S from different simulated biogas containing oxygen(O_(2))and carbon dioxide(CO_(2))and under differ-ent moisture(H_(2)O)contents(0%and 20%)of biochar.The influencing mechanisms of the gas conditions combined with the moisture contents were also investigated.The results showed an H_(2)S removal of 1.75 mg g^(−1)for dry bio-char under pure H_(2)S,4.29 mg g^(−1)for dry biochar under H_(2)S+O_(2),5.29 mg g^(−1)for humid biochar under H_(2)S,and 12.50 mg g^(−1)for humid biochar under H_(2)S+O_(2).For dry DFW-BC,the high Fe content was responsible for the O_(2)enhancement.In contrast,O_(2)+H_(2)O activated the catalytic H_(2)S oxidation of the less reactive minerals(mainly Ca).The inhibition of CO_(2)on H_(2)S adsorption was not obvious for dry DFW-BC;the specific pore structure may have provided a buffer against the physisorption competition of CO_(2).However,when H_(2)O was present on DFW-BC,the changes in critical biochar properties and sulfur speciation as opposed to that without H_(2)O implied an evident occurrence of CO_(2)chemisorption.This CO_(2)chemisorption partially hindered O_(2)+H_(2)O enhancement,decreasing the H_(2)S removal capacity from 12.50 to 8.88 mg g^(−1).The negative effect was ascribed to mineral carbonation of CO_(2),neutralizing the alkaline surface and immobilizing metal oxides,which thus reduced the acceleration in H_(2)S dissociation and activa-tion in catalytic H_(2)S oxidation by O_(2)+H_(2)O.展开更多
Yaks are well-adapted to the harsh environment of the Tibetan Plateau,and they emit less enteric methane(CH_(4))and digest poor-quality forage better than cattle.To examine the potential of yak rumen inoculum to mitig...Yaks are well-adapted to the harsh environment of the Tibetan Plateau,and they emit less enteric methane(CH_(4))and digest poor-quality forage better than cattle.To examine the potential of yak rumen inoculum to mitigate CH_(4)production and improve digestibility in cattle,we incubated substrate with rumen inoculum from yak(YRI)and cattle(CRI)in vitro in five ratios(YRI:CRI):(1)0:100(control),(2)25:75,(3)50:50,(4)75:25 and(5)100:0 for 72 h.The YRI:CRI ratios of 50:50,75:25 and 100:0 produced less total gas and CH_(4)and accumulated less hydrogen(H_(2))than0:100(control)at most time points.From 12 h onwards,there was a linear decrease(P<0.05)in carbon dioxide(CO_(2))production with increasing YRI:CRI ratio.At 72 h,the ratios of 50:50 and 75:25 had higher dry matter(+7.71%and+4.11%,respectively),as well as higher acid detergent fiber digestibility(+15.5%and+7.61%,respectively),when compared to the 0:100 ratio(P<0.05).Increasing the proportion of YRI generally increased total VFA concentrations,and,concomitantly,decreased the proportion of metabolic hydrogen([2H])incorporated into CH_(4),and decreased the recovery of[2H].The lower[2H]recovery indicates unknown[2H]sinks in the culture.Estimated Gibbs free energy changes(ΔG)for reductive acetogenesis were negative,indicating the thermodynamic feasibility of this process.It would be beneficial to identify:1)the alternative[2H]sinks,which could help mitigate CH_(4)emission,and 2)core microbes involved in fiber digestion.This experiment supported lower CH_(4)emission and greater nutrient digestibility of yaks compared to cattle.Multi-omics combined with microbial culture technologies developed in recent years could help to better understand fermentation differences among species.展开更多
In this editorial,we comment on the article by Qin et al,recently published in the World Journal of Gastrointestinal Oncology.Malignant tumors of the digestive tract represent a significant health threat.Kinesin famil...In this editorial,we comment on the article by Qin et al,recently published in the World Journal of Gastrointestinal Oncology.Malignant tumors of the digestive tract represent a significant health threat.Kinesin family member 14(KIF14),a critical kinesin,is pivotal in the proliferation,migration,and invasion of tumor cells.It has emerged as a focal point in recent studies of malignant tumors in the digestive tract.This article reviews the current research on KIF14 within these tumors and details its significant role in tumor cell behaviors,including proliferation,apo-ptosis,migration,invasion,and angiogenesis,alongside the regulatory mechanisms of the associated intracellular signaling pathways.Additionally,it explores the clinical value of KIF14 as a potential biomarker for early diagnosis,disease monitoring,and prognostic evaluation in malignant tumors of the digestive tract.The article concludes by introducing the potential regulatory role of traditional Chinese medicine,aiming to combine the strengths of both modern and traditional medical approaches to enhance treatment outcomes and prognosis for patients with these tumors.展开更多
Gene expression and the content of hormones regulating feed intake and digestion are crucial for understanding gastric evacuation(GE)and feeding frequency in fish.This study assessed the effects of temperature and siz...Gene expression and the content of hormones regulating feed intake and digestion are crucial for understanding gastric evacuation(GE)and feeding frequency in fish.This study assessed the effects of temperature and size on these parameters by examining the domestication of steelhead trout(Oncorhynchus mykiss)at four temperatures(8℃,12℃,16℃,and 20℃)and with two sizes(75.99 g±10.48 g and 140.21 g±22.08 g)over two weeks.The trout were fasted for 72 h before the GE trial to ensure complete gastric emptying.In each GE trial,the expressions of peptide tyrosine(PYY),cholecystokinin(CCK),and ghrelin genes,along with corresponding serum hormone levels,were measured before feeding and at 0 h and 24 h after feeding,in conjunction with feed intake and 24-h gastric content mass.Results revealed significant effects of temperature on the expression of the three gastric genes.CCK expression increased at 8℃,correlating with reduced feed intake,while PYY and CCK increased at 20℃,correlating with accelerated gastric evacuation.Size significantly influenced serum levels of all three hormones,but the interaction between temperature and size did not affect PYY and ghrelin expression or their serum contents.This study provides molecular insights into how temperature and size regulate the digestion of steelhead trout,offering a theoretical framework for optimizing feeding frequency in aquaculture practices.展开更多
基金supported by the National Key Research and Development Program of China(No.2020YFC1908702)the National Natural Science Foundation of China(No.52131002)+1 种基金the Science and Technology Commission of Shanghai Municipality(No.22dz1209200)China Three Gorges Corporation(No.202403018).
文摘High ammonia-nitrogen digestate has become a key bottleneck limiting the anaerobic digestion of organic solid waste.Vacuum ammonia stripping can simultaneously remove and recover ammonia nitrogen,which has attracted a lot of attention in recent years.To investigate the parameter effects on the efficiency and mass transfer,five combination conditions(53℃ 15 kPa,60°C 20 kPa,65°C 25 kPa,72°C 35 kPa,and 81°C 50 kPa)were conducted for ammonia stripping of sludge digestate.The results showed that 80%of ammonia nitrogen was stripped in 45 min for all experimental groups,but the ammonia transfer coefficient varied under different conditions,which increased with the rising of boiling point temperature,and reached the maximum value(39.0 mm/hr)at 81°C 50 kPa.The ammonia nitrogen removal efficiency was more than 80%for 30 min vacuum stripping after adjusting the initial pH to above 9.5,and adjustment of the initial alkalinity also affects the pH value of liquid digestate.It was found that pH and alkalinity are the key factors influencing the ammonia nitrogen dissociation and removal efficiency,while temperature and vacuum mainly affect the ammonia nitrogen mass transfer and removal velocity.In terms of the mechanism of vacuum ammonia stripping,it underwent alkalinity destruction,pH enhancement,ammonia nitrogen dissociation,and free ammonia removal.In this study,two-stage experiments of alkalinity destruction and ammonia removal were also carried out,which showed that the two-stage configuration was beneficial for ammonia removal.It provides a theoretical basis and practical technology for the vacuum ammonia stripping from liquid digestate of organic solid waste.
文摘The integration of sustainable technologies in waste management systems has become imperative in addressing the escalating challenges of agricultural productivity and sustainability. Plugs are essential when starting crop production in controlled environment agriculture (CEA) setups and greenhouses. Horticultural crops such as vegetables, fruiting, and ornamental plants that utilize plugs have demonstrated higher success rates, healthier plants, and higher total yields. The APS Laboratory for Sustainable Agriculture explored the innovative utilization of digestate from the Home Water-Energy-Food Systems (H-WEF). The H-WEF system converts household food waste into biogas, electricity, and nutrient-rich digestate. The digestate from the H-WEF system was used to produce agricultural plugs, presenting a novel approach to circular resource utilization. We carried out the growth of Rex Butterhead Lettuce Latuca sativa plugs with 1) control system (synthetic fertilizer) and seven different treatments, 2) 5% Digestate—95% RO Water (5D–95RO);3) 10% Digestate—90% RO Water (10D–90RO);4) 15% Digestate—85% RO Water (15D–85RO);5) 20% Digestate—80% RO Water (20D–80RO);6) 25% Digestate—75% RO Water (25D–75RO);7) 30% Digestate—70% RO Water (30D–70RO);8) 35% Digestate—65% RO Water (35D–65RO). The plugs were cultivated for 15 days in a controlled environment until two leaves had developed after the cotyledon. After 15 days, we collected data on wet weight (g), plug head area (cm2), total leaf area (cm2), total chlorophyll content (mg/cm2), and dry weight (g). In addition, we collected data on the Leaf Area Index (LAI, cm2/cm2) and Specific Leaf Area (SLA, cm2/g). The synthetic fertigation yielded a higher wet weight than the following treatments: 5D–95RO, 10D–90RO, and 35D–65RO. While the 30D–70RO treatment produced a larger plug head than all other treatments. The digestate-based fertilizers were comparable to the synthetic fertilizer at dilutions of 25D–75RO and 30D–70RO. This study underscores the viability of using digestate for plug production, providing crucial insights for growers navigating the challenges of sustainable agricultural practices.
文摘The paper presents the results of a two-year research of properties and the way of use of briquettes and pellets made of separated and partially dehydrated digestate from agricultural BGSs (biogas stations). Digestate is a by-product of BGS. There are approximately 170 agricultural BGSs operating in the Czech Republic. Unprocessed digestate with the dry mass content around 6% is usually applied to soil as a lighter mineral fertilizer. If digestate is separated and the separated solid component of the digestate is further dehydrated to 14 % moisture, it can be processed by pressing to the form of very solid pellets and briquettes, also with various additives. It was also ascertained that mechanical strength and shape of briquettes does not change due to long-term storage. In this form, the compressed digestate can be used in various ways. One of the ways is its energetic use by direct burning. That is why we have observed its calorific value and combustion heat. Another alternative use of compressed digestate from BGS is its application in targeted treatment of in particular mechanical properties of soil and its water regime. The briquettes and pellets have great water sorption properties--the briquette retains water and as a consequence grows up to four times in size. This specific property was analysed and it was ascertained that the speed of water sorption depends on the composition of the compressed mixture (i.e., the type of material and the size of its particles), but also on the total weight of the produced briquettes (i.e., their size). Similar dependency was ascertained for other briquette materials that were analysed.
基金the Australian Research Council Discovery Early Career Researcher Award(No.DE160100667)the Australian Research Council Discovery Project(No.DP170102812)+1 种基金the Philanthropic Grant for Early Career Engineering Researcher(No.GE12015)the postdoctoral fellowship support from the Japan Society for the Promotion of Science(JSPS)(No.268245)
文摘The importance of enhancing sludge dewaterability is increasing due to the considerable impact of excess sludge volume on disposal costs and on overall sludge management. This study presents an innovative approach to enhance dewaterability of anaerobic digestate(AD) harvested from a wastewater treatment plant. The combination of zero valent iron(ZVI, 0–4.0 g/g total solids(TS)) and hydrogen peroxide(HP, 0–90 mg/g TS) under pH 3.0 significantly enhanced the AD dewaterability. The largest enhancement of AD dewaterability was achieved at 18 mg HP/g TS and 2.0 g ZVI/g TS, with the capillary suction time reduced by up to 90%. Economic analysis suggested that the proposed HP and ZVI treatment has more economic benefits in comparison with the classical Fenton reaction process. The destruction of extracellular polymeric substances and cells as well as the decrease of particle size were supposed to contribute to the enhanced AD dewaterability by HP + ZVI conditioning.
基金supported by the National Natural Science Foundation of China(31861133018,41830751,42107320)the Hainan University Startup Fund,China(KYQD(ZR)-20098).
文摘The inhibition of nitrification by mixing nitrification inhibitors(NI)with fertilizers is emerging as an effective method to reduce fertilizer-induced nitrous oxide(N_(2)O)emissions.The additive 3,4-dimethylpyrazole phosphate(DMPP)apparently inhibits ammonia oxidizing bacteria(AOB)more than ammonia oxidizing archaea(AOA),which dominate the nitrification in alkaline and acid soil,respectively.However,the efficacy of DMPP in terms of nitrogen sources interacting with soil properties remains unclear.We therefore conducted a microcosm experiment using three typical Chinese agricultural soils with contrasting pH values(fluvo-aquic soil,black soil and red soil),which were fertilized with either digestate or urea in conjunction with a range of DMPP concentrations.In the alkaline fluvo-aquic soil,fertilization with either urea or digestate induced a peak in N_(2)O emission(60μg N kg^(-1)d^(-1))coinciding with the rapid nitrification within 3 d following fertilization.DMPP almost eliminated this peak in N_(2)O emission,reducing it by nearly 90%,despite the fact that the nitrification rate was only reduced by 50%.In the acid black soil,only the digestate induced an N_(2)O emission that increased gradually,reaching its maximum(20μg N kg^(-1)d^(-1))after 5–7 d.The nitrification rate and N_(2)O emission were both marginally reduced by DMPP in the black soil,and the N_(2)O yield(N_(2)O-N per NO2–+NO3–-N produced)was exceptionally high at 3.5%,suggesting that the digestate induced heterotrophic denitrification.In the acid red soil,the N_(2)O emission spiked in the digestate and urea treatments at 50 and 10μg N kg^(-1)d^(-1),respectively,and DMPP reduced the rates substantially by nearly 70%.Compared with 0.5%DMPP,the higher concentrations of DMPP(1.0 to 1.5%)did not exert a significantly(P<0.05)better inhibition effect on the N_(2)O emissions in these soils(either with digestate or urea).This study highlights the importance of matching the nitrogen sources,soil properties and NIs to achieve a high efficiency of N_(2)O emission reduction.
基金partially funded by the GTCLC-NEG project,which received funding from the European Union’s Horizon 2020 Research and Innovation Programme under the Marie Sklodowska-Curie Grant Agreement (101018756)the Brisk 2 European project (731101)for funding this project.The project acronym was B2PB-SIN2-1001,and the project title was“Optimization of catalytic pyrolysis of digestate and sewage sludge.”。
文摘Catalytic pyrolysis of digestate to produce aromatic hydrocarbons can be combined with anaerobic fermentation to effectively transform and utilize all biomass components,which can achieve the meaningful purpose of transforming waste into high-value products.This study explored whether catalytic pyrolysis of digestate is feasible to prepare aromatic hydrocarbons by analyzing the thermogravimetric characteristics,pyrolysis characteristics,and catalytic pyrolysis characteristics of digestate.For digestate pyrolysis,an increase in temperature was found to elevate the CO,CH_4,and monocyclic aromatic hydrocarbon(benzene,toluene,and xylene;BTX)content,whereas it decreased the contents of phenols,acids,aldehydes,and other oxygenates.Furthermore,the catalytic pyrolysis process effectively inhibited the acids,phenols,and furans in the liquid,whereas the yield of BTX increased from 25.45%to 45.99%,and the selectivity of xylene was also increased from 10.32%to 28.72%after adding ZSM-5.ZSM-5 also inhibited the production of nitrogenous compounds.
基金This work is supported by the National Key R&D Program of China(No.2018YFD1100600).The authors appreciate Ms.Ning Zhang,Mr.WeiWang,and Mr.Jing Guo for their assistances in analysis.
文摘The development of methods for the efficient treatment and application of food waste digestate is an important research goal.Vermicomposting via housefly larvae is an efficient way to reduce food waste and achieve its valorization,however,studies on the application and performance of digestate in vermicomposting are rarely.The present study aimed to investigate the feasibility of the co-treatment of food waste and digestate as an additive via larvae.Restaurant food waste(RFW)and household food waste(HFW)were selected to assess the effects of waste type on vermicomposting performance and larval quality.Waste reduction rates of 50.9%–57.8%were observed in the vermicomposting of food waste mixed with digestate at a ratio of 25%,which were slightly lower than those for treatments without the addition of digestate(62.8%–65.9%).The addition of digestate increased the germination index,with a maximum value of 82%in the RFW treatments with 25%digestate,and decreased the respiration activity,with a minimum value of 30 mg-O_(2)/g-TS.The larval productivity of 13.9%in the RFW treatment system with a digestate rate of 25%was lower that without digestate(19.5%).Materials balance shows that larval biomass and metabolic equivalent had decreasing trends as the amount of digestate increased and HFW vermicomposting exhibited lower bioconversion efficiency than that of RFW treatment system regardless of the addition of digestate.These results suggest that mixing digestate at a low ratio(25%)during vermicomposting of foodwaste especially RFW could lead to considerable larval biomass and generate relatively stable residues.
基金supported by the Fundamental Research Funds for the Central Universities(No.20822041B4013)Key Laboratory of Development and Application of Rural Renewable Energy,Ministry of Agriculture and Rural Affairs,China(No.18H0491)。
文摘A vacuum membrane distillation(VMD)process with permeate fractional condensation on membrane downstream has been developed for simultaneous recovery of phosphorus and nitrogen from liquid digestate.The polytetrafluoroethylene(PTFE)membrane flux could reach 6000 g·m-2·h-1 with the rejection efficiency of total phosphorus(TP)over 0.99,under the condition of flowrate being 120 L·h-1 and temperature being 40°C.Membrane fouling occurred with a film of organics and microorganism deposited on the surface of the membrane.Membrane flux could be reversed after the membrane was rinsed by water.Higher feed temperature and flowrate could improve the membrane flux,while hardly affect the rejection efficiency of total phosphorus.The concentration of TP could reach 1600 mg·L-1 after membrane distillation,which is about 5 times of that in initial liquid digestate.On the downstream of the membrane,some of the permeate vapor was condensed under the vacuum condition and most of water was collected here.The remaining vapor enriched with total nitrogen(TN)was compressed and pumped to the atmospheric condition to condense.The TN concentration in atmospheric condensate was as high as 7000 mg·L-1 with the process separation factor for ammonia being enhanced to 114.
文摘This study focused on the characterization of digestates resulting from anaerobic digestion of manioc effluents from attiéké factories. Two types of digestate were characterized, one consisting of manioc effluent + urine and another composed of manioc effluent + urine + cow dung. As a result, these residues of bio-digestion rich in nutrients (NPK) can be used as agricultural fertilizer. Moreover, the determination of some microorganisms and heavy metals digestates allowed to better appreciate its fertilizing quality. These parameters remained in accordance with the quality standards of a digestate prescribed. These results show that digestates from anaerobic co-digestion of manioc effluents, urine and cow dung can be used without fear as an agricultural biofertilizer.
文摘Anaerobic digestion of biomasses originates different products, the most abundant of which are methane and carbon dioxide. During this process, a 60-70% organic matter reduction occurs and the final product, the digestate, is charac- terized by high biological stability and high contents of recalcitrant organic molecules and nutrients. In the present work digestates obtained by different mixture of biomasses in a full-scale co-digestion plant operating in Italy were characterized as whole samples without any pre-treatment or extraction by means of Fourier transform infrared spec- troscopy and fluorescence spectroscopy in the synchronous-scan mode and results were compared to those obtained on the single fresh substrates. Biomasses considered were: beef cattle slurry, maize or sorghum silage, agro-industrial residues, olive residues and olive mill wastewater. These substrates exhibited typical spectra related to their different chemical composition. Results obtained on digestates provided evidence of distinctive characteristic of the final product as a function of the different composition of the biomasses loaded into the digestion plant. We concluded that FTIR and fluorescence spectra of digestates produced in a real co-digestion plant “inherit” the main spectroscopic features of the organic wastes from which they are produced. Spectroscopic techniques used in this work succeeded in qualitatively characterizing and differentiating digestates obtained from biomasses of different chemical composition.
文摘The possibility of producing biogas and methane from two phases olive pomace was considered using anaerobic digestion and the microbial characteristic of digestate for the agrarian use was analyzed. In the work, the main aim was to obtain biogas, made from at least 50% methane, and a digestate that can be used in the field of agronomy, from the anaerobic digestion of the substrates. The tests were carried out by digesting different mixtures of the two-phase pomace, mulberry leaves and mud civil wastewater (pre-digested) in a batch system and in anaerobic mesophilic conditions (35 ~C). The substrates were properly homogenized in order to obtain mixtures of known and uniform composition. The initial and final STi (Total Solids) and initial SVi (Volatile Solids), the concentration of chemical oxygen demand and total phenols were measured and the process yield (m3/t SV) was quantified with standard procedure. The objectives of the study were the analysis of microbial biodiversity developed during fermentation of mixtures based products and the microbial communities corresponding to Eubacteria, Archaea and Fungiwas analyzed. The suitability of the digestate for agronomical use was evaluated by estimating pathogens bacteria that may be present and by index of inhibition of plant organisms model.
基金supported by the National Key Research&Development Program of Ministry of Science and Technology of the People’s Republic of China(grant number 2018YFC1900901).
文摘To improve anaerobic digestion(AD)efficiency of rice straw,solid alkaline CaO and the liquid fraction of digestate(LFD)were used as pretreatment agents of rice straw.The results showed that AD performance of rice straw with CaOLFD pretreatment was optimal in different pretreatment methods of the CaO+LFD,CaOLFD,LFD+CaO,CaO,and LFD.The maximum methane yield(314 ml(g VS)^(-1))and the highest VFAs concentration(14851 mg·L^(-1) on day 3)of the CaOLFD pretreatment group were 81%and 118%higher than that of the control group,respectively.Under the action of solid alkaline CaO,the bacteria of Clostridium,Atopostipes,Sphaerochaeta,Tissierella,Thiopseudomonas,Rikenellaceae,and Sedimentibacter could build up co-cultures with the archaeal of Methanosaeta,Methanobacterium,and Methanosarcina performing direct interspecies electron transfer(DIET)and improving AD performance of rice straw.Therefore,the combined pretreatment using CaO and LFD could not only pretreat rice straw but also stimulate co-cultures of microorganism to establish DIET enhancing AD efficiency.
文摘Anaerobic digestion is a process that is widely used for the treatment of organic wastes. The digestate can be used as a soil amendment or crop fertiliser. The aims of our work were to evaluate 1) the physicochemical composition and pathogen content in a digestate from poultry manure, according to international regulations, and 2) the effect of its soil application on the major chemical and biological soil properties and on the growth of Lactuca sativa. The experiment consisted of two groups of pots(with and without crop). Treatments applied to each group were as follows: low and high doses of digestate and inorganic fertiliser, and no application(control)(low dose: 70 kg nitrogen(N) ha^(-1) and 21 kg phosphorus(P) ha^(-1); high dose: 210 kg N ha^(-1) and 63 kg P ha^(-1)). Soil samples were taken 7 and 34 d(harvest) after treatment applications. Heavy metal and pathogen contents in the digestate were below the upper limit values. Despite the high pH and electrical conductivity values of the digestate, both soil parameters presented acceptable values for crop growth. Although there were no initial increases in total inorganic N and available P in soil with digestate application, an increase in the fresh weight of crop was observed with the high dose application. This is probably associated with the slow nutrient release from the digestate during the development of the crop. Changes in the microbial community were temporary and occurred at the initial sampling stage of the experiment.
基金the National Natural Science Foundation of China(No.51406032)Natural Science Foundation of Heilongjiang Province(No.E201406)+1 种基金Federal Funding of Heilongjiang Province(No.LBH-Z13044)National High-tech R&D Program of China(No.2014AA022001).
文摘This study investigated the effect of the digestate application depth on soil nitrogen volatilization and vertical distribution in black loam soil and sandy loam column.The contents of soil moisture,TKN(total Kjeldahl nitrogen),ammonium nitrogen,nitrate nitrogen,and the extent of ammonia volatilization were tested by applying digestate at depths of 0 cm,2 cm,6 cm,10 cm,15 cm and 20 cm,respectively.The experimental results showed that ammonia volatilization mainly occurred in the first 10 days and reduced significantly when the application depth was deeper than 10 cm.At the same application depth,compared with the black loam,the nitrogen loss in sandy loam through ammonia volatilization was less,and the penetration depth of nitrate nitrogen and ammonium nitrogen were all deeper.In the same soil,nitrate nitrogen penetrated deeper than ammonium nitrogen at all application depths.
文摘To investigate the in vitro digestion and fermentation properties of soybean oligosaccharides(SBOS)extracted from defatted soybean meal,the changes in monosaccharide composition and molecular mass were analyzed.Subsequently,the effect of SBOS on microbial community structure and metabolites was studied by 16S rRNA gene sequencing and untargeted metabolomics based on liquid chromatography-mass spectrometry.Results showed that SBOS was not easily enzymolyzed during simulated digestion and could reach the large intestine through the digestive system.The significant decrease in the molecular mass of SBOS after in vitro fermentation indicated its utilization by the gut microbiota,which increased the contents of short-chain fatty acids and lactic acid,thereby reducing the pH of the fermentation broth.Moreover,the core community was found to consist of Blautia,Lactobacillaceae,and Pediococcus.SBOS up-regulated beneficial differential metabolites such as myo-inositol,lactose,and glucose,which were closely related to galactose,amino sugar,and nucleotide sugar metabolism.This study will provide a reference for exploring the relationship between the gut microbiota and the metabolites of SBOS,and provide a basis for the development and application of SBOS as an ingredient for functional products.
基金The authors are grateful for the financial support from the National Key Technology Research and Development Programs,China(No.2018YFC1901405)the National Natural Science Foundation of China(Grant No.52100167)+3 种基金the Natural Science Foundation of Hebei Province,China(No.B2020203024)the Key Research and Development Plan of Hebei Province,China(No.21327312D)the Young and Middle-Aged Science and Technology Innovation Leadership Talents Project of Xinjiang Production and Construction Corps,China(No.2019CB028)the Science and Technology Public Relations Projects in Key Fields of Xinjiang Production and Construction Corps,China(No.2019AB028).
文摘The formation of humic-like acids(HLAs)is an essential process for converting liquid digestate into organic soil amendments to enhance agricultural sustainability.The aim of this study was to investigate the impact of oxygen and/or MnO_(2)on the production of HLAs.Herein,abiotic humification performance of the digestate dissolved organic matter(DOM)is investigated with fluxes of air and N2 in the absence and presence of MnO_(2).Our results demonstrated that the fate of digestate DOM greatly depends on the oxidizing environment,the MnO_(2)enhanced nitrogen involved in the formation of HLAs.The synergistic effects of MnO_(2)and oxygen effectively improved the production of HLAs,and the corresponding component evolution was analyzed using spectroscopic evidence.The twodimensional correlation spectroscopy results demonstrated that the reaction sequence of digestate DOM followed the order of protein-like substances,substances with an absorbance at 325 nm,substances with UV absorbance at 254 nm and HLAs.Additionally,excitation emission matrix fluorescence combined with parallel factor analysis(EEM-PARAFAC)showed that tryptophan-like C3 was more prone to transformation than tyrosine-like C2 and was responsible for the humification process.The substance with an absorbance at 325 nm was a reaction intermediate in the transformation process of protein-like substances to HLAs.The above findings can be used to promote the production of liquid fertilizer associated with carbon sequestration as well as the sustainable development of biogas production.
基金the National Key R&D Program of China(2018YFC1902903)National Natural Science Foundation of China(22176005)the Fundamental Research Funds for the Central Universities,Sun Yat-sen University(Project no.22qntd2701).
文摘Hydrogen sulfide(H_(2)S)removal has been a significant concern in various industries.In this study,food waste diges-tate-derived biochar(DFW-BC),a by-product of food waste treatment with abundant minerals,was assessed for removing H_(2)S from different simulated biogas containing oxygen(O_(2))and carbon dioxide(CO_(2))and under differ-ent moisture(H_(2)O)contents(0%and 20%)of biochar.The influencing mechanisms of the gas conditions combined with the moisture contents were also investigated.The results showed an H_(2)S removal of 1.75 mg g^(−1)for dry bio-char under pure H_(2)S,4.29 mg g^(−1)for dry biochar under H_(2)S+O_(2),5.29 mg g^(−1)for humid biochar under H_(2)S,and 12.50 mg g^(−1)for humid biochar under H_(2)S+O_(2).For dry DFW-BC,the high Fe content was responsible for the O_(2)enhancement.In contrast,O_(2)+H_(2)O activated the catalytic H_(2)S oxidation of the less reactive minerals(mainly Ca).The inhibition of CO_(2)on H_(2)S adsorption was not obvious for dry DFW-BC;the specific pore structure may have provided a buffer against the physisorption competition of CO_(2).However,when H_(2)O was present on DFW-BC,the changes in critical biochar properties and sulfur speciation as opposed to that without H_(2)O implied an evident occurrence of CO_(2)chemisorption.This CO_(2)chemisorption partially hindered O_(2)+H_(2)O enhancement,decreasing the H_(2)S removal capacity from 12.50 to 8.88 mg g^(−1).The negative effect was ascribed to mineral carbonation of CO_(2),neutralizing the alkaline surface and immobilizing metal oxides,which thus reduced the acceleration in H_(2)S dissociation and activa-tion in catalytic H_(2)S oxidation by O_(2)+H_(2)O.
基金supported by the National Natural Science Foundation of China(32072757 and U21A20250)。
文摘Yaks are well-adapted to the harsh environment of the Tibetan Plateau,and they emit less enteric methane(CH_(4))and digest poor-quality forage better than cattle.To examine the potential of yak rumen inoculum to mitigate CH_(4)production and improve digestibility in cattle,we incubated substrate with rumen inoculum from yak(YRI)and cattle(CRI)in vitro in five ratios(YRI:CRI):(1)0:100(control),(2)25:75,(3)50:50,(4)75:25 and(5)100:0 for 72 h.The YRI:CRI ratios of 50:50,75:25 and 100:0 produced less total gas and CH_(4)and accumulated less hydrogen(H_(2))than0:100(control)at most time points.From 12 h onwards,there was a linear decrease(P<0.05)in carbon dioxide(CO_(2))production with increasing YRI:CRI ratio.At 72 h,the ratios of 50:50 and 75:25 had higher dry matter(+7.71%and+4.11%,respectively),as well as higher acid detergent fiber digestibility(+15.5%and+7.61%,respectively),when compared to the 0:100 ratio(P<0.05).Increasing the proportion of YRI generally increased total VFA concentrations,and,concomitantly,decreased the proportion of metabolic hydrogen([2H])incorporated into CH_(4),and decreased the recovery of[2H].The lower[2H]recovery indicates unknown[2H]sinks in the culture.Estimated Gibbs free energy changes(ΔG)for reductive acetogenesis were negative,indicating the thermodynamic feasibility of this process.It would be beneficial to identify:1)the alternative[2H]sinks,which could help mitigate CH_(4)emission,and 2)core microbes involved in fiber digestion.This experiment supported lower CH_(4)emission and greater nutrient digestibility of yaks compared to cattle.Multi-omics combined with microbial culture technologies developed in recent years could help to better understand fermentation differences among species.
基金Supported by the 2023 Government-funded Project of the Outstanding Talents Training Program in Clinical Medicine,No.ZF2023165Key Research and Development Projects of Hebei Province,No.18277731D+1 种基金Natural Science Foundation of Hebei Province,No.H202423105Hebei Provincial Administration of Traditional Chinese Medicine,Scientific Research Project,No.2020014.
文摘In this editorial,we comment on the article by Qin et al,recently published in the World Journal of Gastrointestinal Oncology.Malignant tumors of the digestive tract represent a significant health threat.Kinesin family member 14(KIF14),a critical kinesin,is pivotal in the proliferation,migration,and invasion of tumor cells.It has emerged as a focal point in recent studies of malignant tumors in the digestive tract.This article reviews the current research on KIF14 within these tumors and details its significant role in tumor cell behaviors,including proliferation,apo-ptosis,migration,invasion,and angiogenesis,alongside the regulatory mechanisms of the associated intracellular signaling pathways.Additionally,it explores the clinical value of KIF14 as a potential biomarker for early diagnosis,disease monitoring,and prognostic evaluation in malignant tumors of the digestive tract.The article concludes by introducing the potential regulatory role of traditional Chinese medicine,aiming to combine the strengths of both modern and traditional medical approaches to enhance treatment outcomes and prognosis for patients with these tumors.
基金National Key Research and Development Program of China(Nos.2024YFD2400300 and 2019YFD0901000)the Natural National Science Foundation of China(No.32373104).
文摘Gene expression and the content of hormones regulating feed intake and digestion are crucial for understanding gastric evacuation(GE)and feeding frequency in fish.This study assessed the effects of temperature and size on these parameters by examining the domestication of steelhead trout(Oncorhynchus mykiss)at four temperatures(8℃,12℃,16℃,and 20℃)and with two sizes(75.99 g±10.48 g and 140.21 g±22.08 g)over two weeks.The trout were fasted for 72 h before the GE trial to ensure complete gastric emptying.In each GE trial,the expressions of peptide tyrosine(PYY),cholecystokinin(CCK),and ghrelin genes,along with corresponding serum hormone levels,were measured before feeding and at 0 h and 24 h after feeding,in conjunction with feed intake and 24-h gastric content mass.Results revealed significant effects of temperature on the expression of the three gastric genes.CCK expression increased at 8℃,correlating with reduced feed intake,while PYY and CCK increased at 20℃,correlating with accelerated gastric evacuation.Size significantly influenced serum levels of all three hormones,but the interaction between temperature and size did not affect PYY and ghrelin expression or their serum contents.This study provides molecular insights into how temperature and size regulate the digestion of steelhead trout,offering a theoretical framework for optimizing feeding frequency in aquaculture practices.