The aim of this study was to design a new emulsion liquid membrane(ELM)system for the separation of succinic acid from aqueous solutions.The concentration of succinic acid varied from 20 to 60 mmol·L^(-1).The pre...The aim of this study was to design a new emulsion liquid membrane(ELM)system for the separation of succinic acid from aqueous solutions.The concentration of succinic acid varied from 20 to 60 mmol·L^(-1).The prepared ELM system includes tributylamine(TBA)as a carrier,commercial kerosene as a solvent,Span 80 as a surfactant,and Na2CO3as a stripping agent.In order to control the membrane swelling,different values of cyclohexanone were added to the membrane phase.The effect of various empirical variables on the extraction of the succinic acid such as acid concentration in the feed solution,initial feed concentration,carrier concentration,the stirring speed of the extraction,Na2CO3,surfactant,and cyclohexanone concentrations,and treat ratio in the ELM system.The best result was obtained when TBA was used as the carrier.The final acid extraction efficiency was independent of pH variations of the aqueous feed solution.The extraction of succinic acid solution with a concentration of 40 mmol·L^(-1)was improved by increasing the treat ratio 1:7-1:3,stripping phase concentration 0.5-1.5 mol·L^(-1),stirring speed 300-500 r·min^(-1)and cyclohexanone concentration in the membrane phase 1.2-1.6 mol·L^(-1).No considerable effect on the extraction rate was observed for the carrier concentration in the membrane phase.But,the surfactant concentration in the feed phase showed a dual effect on the extraction efficiency.展开更多
Larix olgensis A. Henry(Changbai larch) is a productive commercial species and good candidate for afforestation in northeast China. It is widely planted in lead-stressed soils which can induce oxidative damage in this...Larix olgensis A. Henry(Changbai larch) is a productive commercial species and good candidate for afforestation in northeast China. It is widely planted in lead-stressed soils which can induce oxidative damage in this plant. Increasing tolerance to lead(Pb) stress is therefore of keen interest. A greenhouse experiment was conducted to identify the biomass, physiological responses and Pb accumulation of L. olgensis seedlings to Pb stress under succinic acid(SA) application and to explore the interaction of exogenous SA applications and stress resistance. L. olgensis seedlings were planted in Pb-stressed or unstressed haplic cambisols in pots. In Pb-contaminated soils the seedlings were treated daily with concentrations of SA solutions at a rate approximately equivalent to 0, 0.04,0.2, 1.0, or 2.0 mmol kg-1of soil for 10, 20, and 30 days,respectively. Pb treatment induced damage in the seedlings and led to the inhibition of biomass accumulation in roots,stems and leaves, and a rise in Pb accumulation in fine roots and leaves. Malondialdehyde(MDA) content and electrolyte leakage in leaves significantly increased while peroxidase(POD) activities, soluble protein and photosynthetic pigment contents in leaves were all reduced.Physiological toxicity was promoted with increasing Pb treatment times. When Pb-stressed seedlings were exposed to SA(especially 10.0 mmol L-1 over 20 days), the physiological responses for Pb-only were reversed and the biomass of roots, stems, and leaves dramatically increased.SA facilitated Pb uptake in fine roots and leaves but more Pb accumulated in fine roots. The results demonstrate that exogenous SA alleviates Pb-induced oxidative injuries and improves the tolerance of L. olgensis seedlings to Pb stress.展开更多
In this study, we investigated the essential role of feed solution pH so as to gain insights into the transport mechanisms of succinic acid concentration by osmotically-driven forward osmosis (FO) process. FO perfor...In this study, we investigated the essential role of feed solution pH so as to gain insights into the transport mechanisms of succinic acid concentration by osmotically-driven forward osmosis (FO) process. FO performances including water flux and bidirectional transport of succinate and chloride anions were systematically examined using cellulose triacetate-based FO membrane. Additionally, real seawater was explored as draw solution. Experimental results revealed that the pH-dependent speciation of succinic acid can affect the FO performances. Ionization of succinic acid at higher solution pH enhanced the osmotic pressure of feed solution, thus leading to lower water flux performance. A strong effect was pointed out on the succinate rejection for which nearly 100% rejections were achieved at pH above its pKa2 value. The rejection of succinate increased in the following order of chemical form: C2H4C2O4H2 〈 C2H4C2OH- 〈 C2H4C2O24-. With real seawater as the draw solution, low to moderate water fluxes (〈4 L. m- 2. h- 1 ) were observed. The divalent succinate anion was highly retained in the feed side despite differences in the succinic acid feed concentration at pH of approximately 6.90.展开更多
Solubilities were measured for succinic acid dissolved in cyclohexanone, cyclohexanol and 5 of their mixed solvents at the temperature range from 291. 85 K to 358.37 K using a dynamic method. The solubility data were ...Solubilities were measured for succinic acid dissolved in cyclohexanone, cyclohexanol and 5 of their mixed solvents at the temperature range from 291. 85 K to 358.37 K using a dynamic method. The solubility data were regressed by λh equation, with,the average absolute relative deviation 3.47%. The binary interaction parameter is 0.306 7 for the mixed solvent of oyolohexanone and cyclohexanol was determined by correlating the experimental solubilities with the modified λh equation. When the binary interaction parameter was determined it can be used to extrapolate the solubilities of succinic acid in mixed solvents of cyclohexanone and cyclohexanol at any proportion.The average absolute relative deviation was 7. 69% by using the modified λh equation to correlate the solubility data, however, the average absolute relative deviation was 8.89% by using NRTL equation to correlate the solubility data. The results show that the accuracy of the modified λh equation is better than that of the NRTL equation for the solubility of succinic acid in the 5 mixed solvents of cyclohexanone and cyclohexanol.展开更多
Objective: The aim of our study was to detect whether Vitamin E Succinic Acid (VES) could regulate the expression level of DR5 in the cells and further elucidate the potential mechanisms involving that VES enhances th...Objective: The aim of our study was to detect whether Vitamin E Succinic Acid (VES) could regulate the expression level of DR5 in the cells and further elucidate the potential mechanisms involving that VES enhances the effect of mDRA-6 to eradicate leukemia Raji and K562 cells. Methods: MTT method was used to detect the growth inhibition of VES and mDRA-6 to Raji and K562 cells. Annexin V-FITC/PI double staining assay was used to analysis the apoptosis of leukemia cell. Flow cytometry was used to detect the cell surface DR5 expression. Immunoblotting technique was used to detect the DR5 protein expression. Results: MTT detection showed that 10 μmol/L mDRA-6 on the cell death rates of Raji and K562 cells were 21.98% and 5.23%, respectively. While increasing concentration of VES (5 μmol/L, 10 μmol/L, 20 μmol/L) and mDRA-6 both on the cell viability of Raji or K562 cells, the mortality of Raji cells elevated to 24.67%, 35.65% (P<0.01) and 40.22% (P<0.01), respectively. Similarly, the mortality of K562 cells increase to 6%, 7.89% (P<0.01) and 8.67% (P<0.01), respectively. To further specify the increased cell death rate induced by mDRA-6 and VES, the treated cells were analyzed by Annexin-V/PI staining assay. As shown in Fig. 1, the apoptosis rates of Raji and K562 cells treated with 2 μg/mL mDRA-6 for 12 h were 20.79% and 7.74%. Compared with this, the proportion of apoptotic cells increased upon exposure to 2 μg/mL mDRA-6 combination with 10 μmol/L VES, the apoptosis rates of Raji and K562 cells were 43.18% and 16.99%, respectively. To examine the anticancer effects of a combination strategy based on mDRA-6 and VES. We analyzed whether VES could elevated the expression level of DR5 on Raji and K562 cytomembrane by FACS. Interestingly, after treated with 10 μmol/L VES for 12 h, the expression level of DR5 on Raji and K562 cell surface increased from 50.66% to 70.08%, and 15.02% to 16.38%, respectively. Immune imprinting technology test showed that, different concentrations of VES could increase Raji and K562 cell DR5 protein expression. Conclusion: VES enhances the effect of mDRA-6 to eradicate leukemia Raji and K562 cells. The proper mechanism is VES could enhance the Raji and K562 cell membrane expression of DR5, and VES can also enhance the DR5 protein expression of cells.展开更多
Antioxidant and anti-inflammatory therapy approaches have been in the focus of attention in the treatment of different cancer diseases where oxidative stress has been implicated. Succinic acid has been previously repo...Antioxidant and anti-inflammatory therapy approaches have been in the focus of attention in the treatment of different cancer diseases where oxidative stress has been implicated. Succinic acid has been previously reported to possess radical scavenger, iron chelating and anti-inflammatory properties in the mouse fibroblast. The purpose of this study was to investigate potential therapeutic effects of succinic acid and possible signal pathway involved in the mouse fibroblast. We demonstrated highly potent antioxidant-radical scavenging activities of succinic acid.展开更多
We conduct research on the development of new medicines based on succinic acid, ascorbic acid and rutin. We studied the anti-inflammatory action (exudative inflammation, model of carrageenan-induced paw edema of rats...We conduct research on the development of new medicines based on succinic acid, ascorbic acid and rutin. We studied the anti-inflammatory action (exudative inflammation, model of carrageenan-induced paw edema of rats), the hepatoprotective (injury of rats with carbon tetrachloride) and renal protectie action. In the study, the anti-inflammatory activity of our medicines (exudative inflammation, karahenin model of inflammatory edema of paws rats) is set to ability of suppression of the inflammatory response by 24.4 %. Against the background, the action of carbon tetrachloride observed a positive effect on cholesterol- and pigment- forming liver function. Reducing the activity of enzymes ALT (alanine transaminase) and AST (aspartate transaminase) in groups of animals, which treated with our medication, talks about their ability to recover morpho functional integrity of the membranes of hepatocytes and warn of changes in the liver damage with carbon tetrachloride. Renal protective action screening study found that investigated mixture capable of increasingly lower level of creatinine in the blood of rats: 27.27-39.18 mmol/L in Lespeflan. Similarly, the concentration of urea in the smaller of the studied using mixtures is 5.18 mmol/L, while the application lespeflanu urea concentration slightly higher is 6.78 mmol/L. This shows that hypoazotemic effect is traced compared with the control group, and better than the comparator Lespeflan. Study of acute toxicity showed that the investigated mixture refers to practically nontoxic drugs. It is confirmed the need for further studies on the pharmacological activity of our facility to determine the effect on capillaries and the immune system, and as a result, prevention and treatment of influenza and ARI (acute respiratory infections).展开更多
To evaluate the effects of dietary supplementation with succinic acid on growth performance,flesh quality,glucose,and lipid metabolism of Nile tilapia(Oreochromis niloticus)fed a high-carbohydrate diet(HCD),five iso-n...To evaluate the effects of dietary supplementation with succinic acid on growth performance,flesh quality,glucose,and lipid metabolism of Nile tilapia(Oreochromis niloticus)fed a high-carbohydrate diet(HCD),five iso-nitrogenous and iso-lipidic diets were prepared as follows:HCD(control group)consisting of 55%corn starch and HCD supplemented with 0.5%,1.0%,2.0%,and 4.0%succinic acid,respectively.Tilapia with an initial body weight of 204.90±1.23 g randomly assigned to 15 tanks with 3 replicates per group and 10 fish per tank fed for 8 weeks.Increasing dietary succinic acid supplementation resulted in significant second-order polynomial relationship in the weight gain rate(WGR),specific growth rate(SGR),feed conversion ratio(FCR),protein efficiency rate(PER),viscerosomatic index,condition factor,and contents of muscular crude lipid and glycogen(P<0.05).The hepatosomatic index,mesenteric fat index,liver glycogen content and crude lipid contents of the whole-body and liver demonstrated significantly linear and second-order polynomial relationship(P<0.05).Quadratic curve model analysis based on WGR,SGR,PER,and FCR demonstrated that optimal supplementation with succinic acid in the HCD of Nile tilapia ranged from 1.83%to 2.43%.Fish fed with 1.0%succinic acid had higher muscular hardness,increased the contents of alkali-soluble hydroxyproline in collagen,docosahexaenoic acid(DHA)and n-3 polyunsaturated fatty acid(n-3PUFA)in muscle,and lower total fatty acid content in muscle(P<0.05)compared with the control group.Compared to the control group,dietary supplementation with 1.0%succinic acid significantly increased the contents of total bounding amino acid(arginine,histidine,isoleucine,lysine,methionine,alanine,proline),total flavor amino acid(free aspartic acid),the catalase(CAT)activity and total antioxidant capacity,and the mRNA relative expression levels of CAT,superoxide dismutase(SOD),and nuclearfactor erythroidderived 2-like 2(Nrf2)in muscle(P<0.05).Furthermore,succinic acid supplementation significantly up-regulated mRNA relative expression levels of glycolysis genes(hexokinase 2[HK2],phosphofructokinase,muscle-A[PFKMA],and phosphofructokinase,muscle-B[PFKMB]),a key glycogen synthesis gene(glycogen synthase[GYS]),and lipid catabolism genes(carnitine palmitoyltransferase-1B[CPT1B],hormone sensitive lipase[HSL],and lipoprotein lipase[LPL]),while down-regulating the mRNA relative expression level of fatty acid synthase(FASN)in muscle(P<0.05).In conclusion,dietary supplementation with 1.83%to 2.43%succinic acid improved muscle quality by increasing muscle antioxidant capacity and hardness,changing muscle amino acid and fatty acid composition,and regulating muscle glucose and lipid metabolism.展开更多
Utilizing CO_(2)for bio-succinic acid production is an attractive approach to achieve carbon capture and recycling(CCR)with simultaneous production of a useful platform chemical.Actinobacillus succinogenes and Basfia ...Utilizing CO_(2)for bio-succinic acid production is an attractive approach to achieve carbon capture and recycling(CCR)with simultaneous production of a useful platform chemical.Actinobacillus succinogenes and Basfia succiniciproducens were selected and investigated as microbial catalysts.Firstly,the type and concentration of inorganic carbon concentration and glucose concentration were evaluated.6 g C/L MgCO_(3)and 24 g C/L glucose were found to be the optimal basic operational conditions,with succinic acid production and carbon yield of over 30 g/L and over 40%,respectively.Then,for maximum gaseous CO_(2)fixation,carbonate was replaced with CO_(2)at different ratios.The“less carbonate more CO_(2)”condition of the inorganic carbon source was set as carbonate:CO_(2)=1:9(based on the mass of carbon).This condition presented the highest availability of CO_(2)by well-balanced chemical reaction equilibrium and phase equilibrium,showing the best performance with regarding CO_(2)fixation(about 15 mg C/(L·hr)),with suppressed lactic acid accumulation.According to key enzymes analysis,the ratio of phosphoenolpyruvate carboxykinase to lactic dehydrogenase was enhanced at high ratios of gaseous CO_(2),which could promote glucose conversion through the succinic acid path.To further increase gaseous CO_(2)fixation and succinic acid production and selectivity,stepwise CO_(2)addition was evaluated.50%-65%increase in inorganic carbon utilization was obtained coupled with 20%-30%increase in succinic acid selectivity.This was due to the promotion of the succinic acid branch of the glucose metabolism,while suppressing the pyruvate branch,along with the inhibition on the conversion from glucose to lactic acid.展开更多
The homogeneous and controllable morphology of anhydrous magnesium carbonate(MgCO_(3))particles with excellent properties is difficult to obtain because of a variety of synthetic factors.The effect of succinic acid as...The homogeneous and controllable morphology of anhydrous magnesium carbonate(MgCO_(3))particles with excellent properties is difficult to obtain because of a variety of synthetic factors.The effect of succinic acid as a crystal modifier on the particle morphology transformation of anhydrous MgCO_(3)was investigated by the hydrothermal method.The effect of the addition of succinic acid on the particles was similar to that of temperature change.The morphology of particles with a folded diamond-like shape was gradually uniform,and the particle size was between 3.3 and 7.5μm.Anhydrous MgCO_(3)particles prepared at pH 9 could easily agglomerate,and the average particle size increased from diamond-like to cube-like as the reaction time increased.The interaction between succinic acid and magnesium ions at different concentrations was the main factor responsible for the morphological changes.The pH,temperature,and time affected the molecular motion rate and crystal growth.展开更多
Employing biodegradable plastics is one of the choices to solve white pollution issues.Polybutylene succinate(PBS),as a biodegradable plastic with good stability and heat resistance,is produced by polymerization of su...Employing biodegradable plastics is one of the choices to solve white pollution issues.Polybutylene succinate(PBS),as a biodegradable plastic with good stability and heat resistance,is produced by polymerization of succinic acid and butylene glycol.However,inadequate supply of the direct upstream material succinic acid restricts the development of this industry.In this work,we provide a carbonylative strategy to construct succinic acid derivatives from carbon monoxide(CO),ethylene and alcohols.The reaction catalyzed by palladium catalyst under oxidative conditions.展开更多
Succinic acid is one of the most useful intermediate chemicals that can be produced in a biorefinery approach.In this study,Actinobacillus succinogenes was immobilized to produce succinic acid using non-detoxified cor...Succinic acid is one of the most useful intermediate chemicals that can be produced in a biorefinery approach.In this study,Actinobacillus succinogenes was immobilized to produce succinic acid using non-detoxified corn fiber hydrolysate(CFH)and a control mimicking the sugars in CFH.Tests were carried out in a hollow fiber membrane packed-bed biofilm reactor(HFM–PBR)operated in a continuous mode.Under steady-state conditions,the bioconversion process was characterized in terms of sugar consumption,succinic acid and other organic acid production.Steady states were obtained at dilution rates of 0.025,0.05,0.075,0.1,0.2,and 0.3 h^(-1).The optimal results were achieved at the dilution rate of 0.05 h^(-1)and recirculation rate of 50 ml/min with a maximum succinic acid concentration,yield and productivity of 31.1 g/L,0.61 g/g and 1.56 g/L h,respectively,when control was used.Succinic acid concentration,yield and productivity of 23.4 g/L,0.51 g/g and 1.17 g/L h,respectively,were obtained when CFH was used.Productivity in the HFM–PBR was between 1.3 and 1.9 times higher than productivities for succinic acid production from CFH stated in the literature.The results demonstrated that immobilized A.succinogenes has the potential for effective conversion of an inexpensive biomass feedstock to succinic acid.Furthermore,the process has the potential to serve as a means for value-added chemical biomanufacturing in an integrated corn biorefinery.展开更多
Succinic acid is considered as an important platform chemical. Succinic acid fermentation with Actinobacillus succinogenes strain BE-1 was optimized by central composite design (CCD) using a response surface methodo...Succinic acid is considered as an important platform chemical. Succinic acid fermentation with Actinobacillus succinogenes strain BE-1 was optimized by central composite design (CCD) using a response surface methodology (RSM). The optimized production of succinic acid was predicted and the interactive effects between glucose, yeast extract, and magnesium carbonate were investigated. As a result, a model for predicting the concentration of succinic acid production was developed. The accuracy of the model was confirmed by the analysis of variance (ANOVA), and the validity was further proved by verification experiments showing that percentage errors between actual and predicted values varied from 3.02% to 6.38%. In addition, it was observed that the interactive effect between yeast extract and magnesium carbonate was statistically significant. In conclusion, RSM is an effective and useful method for optimizing the medium components and investigating the interactive effects, and can provide valuable information for succinic acid scale-up fermentation using A. succinogenes strain BE-I.展开更多
Extraction equilibrium features of succinic acid, malic acid,maleic acid and fumaric acid were investi- gated systematically withtrioctylamine (TOA) in chloroform, 4-methyl-2-pentanone (MIBK) and1-octanol. Fourier tra...Extraction equilibrium features of succinic acid, malic acid,maleic acid and fumaric acid were investi- gated systematically withtrioctylamine (TOA) in chloroform, 4-methyl-2-pentanone (MIBK) and1-octanol. Fourier transform-infrared (FTIR) spectroscopic analysisof organic samples loaded with the acid shows that amine forms 1:1complex of ion-pair association with succinic acid, malic acid andmaleic acid, and 1:1, 2:1 complex of ion-pair association withfumaric acid. It is proposed that the complex forms depend on thesecond dissociation constant of the dibasic acid, pK_a2.展开更多
The effect of succinic acid deamidationinduced modification on wheat gluten was investigated in the present study.The changes of surface hydrophobicity,functional properties,secondary structure,and sensibility of prot...The effect of succinic acid deamidationinduced modification on wheat gluten was investigated in the present study.The changes of surface hydrophobicity,functional properties,secondary structure,and sensibility of proteolysis of modified samples were determined.The solubility of deamidated proteins increased in the isoelectric region of untreated wheat gluten.The isoelectric point of succinic acid deamidated wheat gluten was shifted to a basic pH and existed in the broad pH regions.Foaming property and molecular flexibility of wheat gluten were improved after the modification.The hydrolysis degree of the hydrolysates in proteolysis with flavorzyme and pancreatin increased after succinic acid deamidation.Moreover,succinic acid deamidation-induced modification resulted in little change in molecular weight and secondary structure of the protein.Thus,succinic acid could facilitate unfolding protein conformation.In addition,it could improve protein-water interactions,surface properties,and sensibility of the proteolysis of the deamidated wheat gluten.展开更多
The underlying pathophysiology of liver dysfunction in urea cycle disorders(UCDs) is still largely elusive. There is some evidence that the accumulation of urea cycle(UC) intermediates are toxic for hepatocyte mitocho...The underlying pathophysiology of liver dysfunction in urea cycle disorders(UCDs) is still largely elusive. There is some evidence that the accumulation of urea cycle(UC) intermediates are toxic for hepatocyte mitochondria. It is possible that liver injury is directly caused by the toxicity of ammonia. The rarity of UCDs, the lack of checking of iron level in these patients, superficial knowledge of UC and an underestimation of the metabolic role of fumaric acid, are the main reasons that are responsible for the incomprehension of the mechanism of liver injury in patients suffering from UCDs. Owing to our routine clinical practice to screen for iron overload in severely ill neonates, with the focus on the newborns suffering from acute liver failure, we report a case of citrullinemia with neonatal liver failure and high blood parameters of iron overload. We hypothesize that the key is in the decreased-deficient fumaric acid production in the course of UC in UCDs that causes several sequentially intertwined metabolic disturbances with final result of liver iron overload. The presented hypothesis could be easily tested by examining the patients suffering from UCDs, for liver iron overload. This could be easily performed in countries with a high population and comprehensive national register for inborn errors of metabolism. Conclusion: Providing the hypothesis is correct, neonatal liver damage in patients having UCD can be prevented by the supplementation of pregnant women with fumaric or succinic acid, prepared in the form of iron supplementation pills. After birth, liverdamage in patients having UCDs can be prevented by supplementation of these patients with zinc fumarate or zinc succinylate, as well.展开更多
Now the mining of high salt underground brine has been an important aspect of salt lake mining,which is the necessary support to the development of national economy.With the change of underground geological
The glutamate decarboxylase(Gad)system is an important amino acid-dependent acid resistance system commonly found in microorganisms.Actinobacillus succinogenes is one of the best natural producers of succinic acid(SA)...The glutamate decarboxylase(Gad)system is an important amino acid-dependent acid resistance system commonly found in microorganisms.Actinobacillus succinogenes is one of the best natural producers of succinic acid(SA)but lacks glutamate decarboxylase.This study assessed the efects of Gad system introduction into A.succinogenes.The recombinant strains gadB-SW and gadBC-SW were constructed by heterologous expression of gadB alone,or gadB together with gadC,respectively.After 1.0 and 1.5 h of acid stress at pH 4.6,cell survival of gadBC-SW was greater than gadB-SW.The growth of gadB-SW and gadBC-SW was both afected by the expression of heterologous proteins and byγ-aminobutyric acid,with gadBC-SW growth reduced at a neutral pH.SA production in acidic conditions was evaluated by a shake fask and by 3-L bioreactor fermentation.The results showed gadBC-SW to increase SA production by 8.4%in shake fask compared to the parent strain,SW.For a 3-L bioreactor batch fermentation under acidic environment,the highest conversion rate of sugar to SA was observed for gadBC-SW,reaching 96%.However,SA concentration by gadBC-SW was only 47 g/L and 31 g/L at pH 6.5 and pH 6.0,respectively.In summary,the introduction of heterologous gadB and gadC into A.succinogenes not only improved acid tolerance but also infuenced the synthesis of SA and added a metabolic burden.展开更多
文摘The aim of this study was to design a new emulsion liquid membrane(ELM)system for the separation of succinic acid from aqueous solutions.The concentration of succinic acid varied from 20 to 60 mmol·L^(-1).The prepared ELM system includes tributylamine(TBA)as a carrier,commercial kerosene as a solvent,Span 80 as a surfactant,and Na2CO3as a stripping agent.In order to control the membrane swelling,different values of cyclohexanone were added to the membrane phase.The effect of various empirical variables on the extraction of the succinic acid such as acid concentration in the feed solution,initial feed concentration,carrier concentration,the stirring speed of the extraction,Na2CO3,surfactant,and cyclohexanone concentrations,and treat ratio in the ELM system.The best result was obtained when TBA was used as the carrier.The final acid extraction efficiency was independent of pH variations of the aqueous feed solution.The extraction of succinic acid solution with a concentration of 40 mmol·L^(-1)was improved by increasing the treat ratio 1:7-1:3,stripping phase concentration 0.5-1.5 mol·L^(-1),stirring speed 300-500 r·min^(-1)and cyclohexanone concentration in the membrane phase 1.2-1.6 mol·L^(-1).No considerable effect on the extraction rate was observed for the carrier concentration in the membrane phase.But,the surfactant concentration in the feed phase showed a dual effect on the extraction efficiency.
基金financially supported by the National Natural Science Foundation of China(31370613)the Fundamental Research Funds for the Central Universities(2572017CA03)
文摘Larix olgensis A. Henry(Changbai larch) is a productive commercial species and good candidate for afforestation in northeast China. It is widely planted in lead-stressed soils which can induce oxidative damage in this plant. Increasing tolerance to lead(Pb) stress is therefore of keen interest. A greenhouse experiment was conducted to identify the biomass, physiological responses and Pb accumulation of L. olgensis seedlings to Pb stress under succinic acid(SA) application and to explore the interaction of exogenous SA applications and stress resistance. L. olgensis seedlings were planted in Pb-stressed or unstressed haplic cambisols in pots. In Pb-contaminated soils the seedlings were treated daily with concentrations of SA solutions at a rate approximately equivalent to 0, 0.04,0.2, 1.0, or 2.0 mmol kg-1of soil for 10, 20, and 30 days,respectively. Pb treatment induced damage in the seedlings and led to the inhibition of biomass accumulation in roots,stems and leaves, and a rise in Pb accumulation in fine roots and leaves. Malondialdehyde(MDA) content and electrolyte leakage in leaves significantly increased while peroxidase(POD) activities, soluble protein and photosynthetic pigment contents in leaves were all reduced.Physiological toxicity was promoted with increasing Pb treatment times. When Pb-stressed seedlings were exposed to SA(especially 10.0 mmol L-1 over 20 days), the physiological responses for Pb-only were reversed and the biomass of roots, stems, and leaves dramatically increased.SA facilitated Pb uptake in fine roots and leaves but more Pb accumulated in fine roots. The results demonstrate that exogenous SA alleviates Pb-induced oxidative injuries and improves the tolerance of L. olgensis seedlings to Pb stress.
基金the financial support for this work provided by the LRGS/2013/UKM-UKM/PT/03 grant from the Ministry of Education Malaysia
文摘In this study, we investigated the essential role of feed solution pH so as to gain insights into the transport mechanisms of succinic acid concentration by osmotically-driven forward osmosis (FO) process. FO performances including water flux and bidirectional transport of succinate and chloride anions were systematically examined using cellulose triacetate-based FO membrane. Additionally, real seawater was explored as draw solution. Experimental results revealed that the pH-dependent speciation of succinic acid can affect the FO performances. Ionization of succinic acid at higher solution pH enhanced the osmotic pressure of feed solution, thus leading to lower water flux performance. A strong effect was pointed out on the succinate rejection for which nearly 100% rejections were achieved at pH above its pKa2 value. The rejection of succinate increased in the following order of chemical form: C2H4C2O4H2 〈 C2H4C2OH- 〈 C2H4C2O24-. With real seawater as the draw solution, low to moderate water fluxes (〈4 L. m- 2. h- 1 ) were observed. The divalent succinate anion was highly retained in the feed side despite differences in the succinic acid feed concentration at pH of approximately 6.90.
文摘Solubilities were measured for succinic acid dissolved in cyclohexanone, cyclohexanol and 5 of their mixed solvents at the temperature range from 291. 85 K to 358.37 K using a dynamic method. The solubility data were regressed by λh equation, with,the average absolute relative deviation 3.47%. The binary interaction parameter is 0.306 7 for the mixed solvent of oyolohexanone and cyclohexanol was determined by correlating the experimental solubilities with the modified λh equation. When the binary interaction parameter was determined it can be used to extrapolate the solubilities of succinic acid in mixed solvents of cyclohexanone and cyclohexanol at any proportion.The average absolute relative deviation was 7. 69% by using the modified λh equation to correlate the solubility data, however, the average absolute relative deviation was 8.89% by using NRTL equation to correlate the solubility data. The results show that the accuracy of the modified λh equation is better than that of the NRTL equation for the solubility of succinic acid in the 5 mixed solvents of cyclohexanone and cyclohexanol.
基金Supported by grants from the National "863 Plan" (No. 2006AA02A254)Outstanding Talent Program of Henan Province (No. 074200510014)
文摘Objective: The aim of our study was to detect whether Vitamin E Succinic Acid (VES) could regulate the expression level of DR5 in the cells and further elucidate the potential mechanisms involving that VES enhances the effect of mDRA-6 to eradicate leukemia Raji and K562 cells. Methods: MTT method was used to detect the growth inhibition of VES and mDRA-6 to Raji and K562 cells. Annexin V-FITC/PI double staining assay was used to analysis the apoptosis of leukemia cell. Flow cytometry was used to detect the cell surface DR5 expression. Immunoblotting technique was used to detect the DR5 protein expression. Results: MTT detection showed that 10 μmol/L mDRA-6 on the cell death rates of Raji and K562 cells were 21.98% and 5.23%, respectively. While increasing concentration of VES (5 μmol/L, 10 μmol/L, 20 μmol/L) and mDRA-6 both on the cell viability of Raji or K562 cells, the mortality of Raji cells elevated to 24.67%, 35.65% (P<0.01) and 40.22% (P<0.01), respectively. Similarly, the mortality of K562 cells increase to 6%, 7.89% (P<0.01) and 8.67% (P<0.01), respectively. To further specify the increased cell death rate induced by mDRA-6 and VES, the treated cells were analyzed by Annexin-V/PI staining assay. As shown in Fig. 1, the apoptosis rates of Raji and K562 cells treated with 2 μg/mL mDRA-6 for 12 h were 20.79% and 7.74%. Compared with this, the proportion of apoptotic cells increased upon exposure to 2 μg/mL mDRA-6 combination with 10 μmol/L VES, the apoptosis rates of Raji and K562 cells were 43.18% and 16.99%, respectively. To examine the anticancer effects of a combination strategy based on mDRA-6 and VES. We analyzed whether VES could elevated the expression level of DR5 on Raji and K562 cytomembrane by FACS. Interestingly, after treated with 10 μmol/L VES for 12 h, the expression level of DR5 on Raji and K562 cell surface increased from 50.66% to 70.08%, and 15.02% to 16.38%, respectively. Immune imprinting technology test showed that, different concentrations of VES could increase Raji and K562 cell DR5 protein expression. Conclusion: VES enhances the effect of mDRA-6 to eradicate leukemia Raji and K562 cells. The proper mechanism is VES could enhance the Raji and K562 cell membrane expression of DR5, and VES can also enhance the DR5 protein expression of cells.
文摘Antioxidant and anti-inflammatory therapy approaches have been in the focus of attention in the treatment of different cancer diseases where oxidative stress has been implicated. Succinic acid has been previously reported to possess radical scavenger, iron chelating and anti-inflammatory properties in the mouse fibroblast. The purpose of this study was to investigate potential therapeutic effects of succinic acid and possible signal pathway involved in the mouse fibroblast. We demonstrated highly potent antioxidant-radical scavenging activities of succinic acid.
文摘We conduct research on the development of new medicines based on succinic acid, ascorbic acid and rutin. We studied the anti-inflammatory action (exudative inflammation, model of carrageenan-induced paw edema of rats), the hepatoprotective (injury of rats with carbon tetrachloride) and renal protectie action. In the study, the anti-inflammatory activity of our medicines (exudative inflammation, karahenin model of inflammatory edema of paws rats) is set to ability of suppression of the inflammatory response by 24.4 %. Against the background, the action of carbon tetrachloride observed a positive effect on cholesterol- and pigment- forming liver function. Reducing the activity of enzymes ALT (alanine transaminase) and AST (aspartate transaminase) in groups of animals, which treated with our medication, talks about their ability to recover morpho functional integrity of the membranes of hepatocytes and warn of changes in the liver damage with carbon tetrachloride. Renal protective action screening study found that investigated mixture capable of increasingly lower level of creatinine in the blood of rats: 27.27-39.18 mmol/L in Lespeflan. Similarly, the concentration of urea in the smaller of the studied using mixtures is 5.18 mmol/L, while the application lespeflanu urea concentration slightly higher is 6.78 mmol/L. This shows that hypoazotemic effect is traced compared with the control group, and better than the comparator Lespeflan. Study of acute toxicity showed that the investigated mixture refers to practically nontoxic drugs. It is confirmed the need for further studies on the pharmacological activity of our facility to determine the effect on capillaries and the immune system, and as a result, prevention and treatment of influenza and ARI (acute respiratory infections).
基金supported by the China Agniculture Research System (No.CARS-46)the National Key Research and Devel-opment Program of China (No.2018YFD0900400).
文摘To evaluate the effects of dietary supplementation with succinic acid on growth performance,flesh quality,glucose,and lipid metabolism of Nile tilapia(Oreochromis niloticus)fed a high-carbohydrate diet(HCD),five iso-nitrogenous and iso-lipidic diets were prepared as follows:HCD(control group)consisting of 55%corn starch and HCD supplemented with 0.5%,1.0%,2.0%,and 4.0%succinic acid,respectively.Tilapia with an initial body weight of 204.90±1.23 g randomly assigned to 15 tanks with 3 replicates per group and 10 fish per tank fed for 8 weeks.Increasing dietary succinic acid supplementation resulted in significant second-order polynomial relationship in the weight gain rate(WGR),specific growth rate(SGR),feed conversion ratio(FCR),protein efficiency rate(PER),viscerosomatic index,condition factor,and contents of muscular crude lipid and glycogen(P<0.05).The hepatosomatic index,mesenteric fat index,liver glycogen content and crude lipid contents of the whole-body and liver demonstrated significantly linear and second-order polynomial relationship(P<0.05).Quadratic curve model analysis based on WGR,SGR,PER,and FCR demonstrated that optimal supplementation with succinic acid in the HCD of Nile tilapia ranged from 1.83%to 2.43%.Fish fed with 1.0%succinic acid had higher muscular hardness,increased the contents of alkali-soluble hydroxyproline in collagen,docosahexaenoic acid(DHA)and n-3 polyunsaturated fatty acid(n-3PUFA)in muscle,and lower total fatty acid content in muscle(P<0.05)compared with the control group.Compared to the control group,dietary supplementation with 1.0%succinic acid significantly increased the contents of total bounding amino acid(arginine,histidine,isoleucine,lysine,methionine,alanine,proline),total flavor amino acid(free aspartic acid),the catalase(CAT)activity and total antioxidant capacity,and the mRNA relative expression levels of CAT,superoxide dismutase(SOD),and nuclearfactor erythroidderived 2-like 2(Nrf2)in muscle(P<0.05).Furthermore,succinic acid supplementation significantly up-regulated mRNA relative expression levels of glycolysis genes(hexokinase 2[HK2],phosphofructokinase,muscle-A[PFKMA],and phosphofructokinase,muscle-B[PFKMB]),a key glycogen synthesis gene(glycogen synthase[GYS]),and lipid catabolism genes(carnitine palmitoyltransferase-1B[CPT1B],hormone sensitive lipase[HSL],and lipoprotein lipase[LPL]),while down-regulating the mRNA relative expression level of fatty acid synthase(FASN)in muscle(P<0.05).In conclusion,dietary supplementation with 1.83%to 2.43%succinic acid improved muscle quality by increasing muscle antioxidant capacity and hardness,changing muscle amino acid and fatty acid composition,and regulating muscle glucose and lipid metabolism.
基金supported by the Beijing Nova Program(No.Z201100006820022)the National Natural Science Foundation of China(Nos.52100023,U20B2022)+2 种基金the China Postdoctoral Science Foundation(No.2020M680314)the Key Science and Technology Development Program of Xinjiang Corps(No.2021DB006)the EU ACT Coo CE ERA-NET program cofunded with EUDP-2021-Ⅱ(No.64021-2006)。
文摘Utilizing CO_(2)for bio-succinic acid production is an attractive approach to achieve carbon capture and recycling(CCR)with simultaneous production of a useful platform chemical.Actinobacillus succinogenes and Basfia succiniciproducens were selected and investigated as microbial catalysts.Firstly,the type and concentration of inorganic carbon concentration and glucose concentration were evaluated.6 g C/L MgCO_(3)and 24 g C/L glucose were found to be the optimal basic operational conditions,with succinic acid production and carbon yield of over 30 g/L and over 40%,respectively.Then,for maximum gaseous CO_(2)fixation,carbonate was replaced with CO_(2)at different ratios.The“less carbonate more CO_(2)”condition of the inorganic carbon source was set as carbonate:CO_(2)=1:9(based on the mass of carbon).This condition presented the highest availability of CO_(2)by well-balanced chemical reaction equilibrium and phase equilibrium,showing the best performance with regarding CO_(2)fixation(about 15 mg C/(L·hr)),with suppressed lactic acid accumulation.According to key enzymes analysis,the ratio of phosphoenolpyruvate carboxykinase to lactic dehydrogenase was enhanced at high ratios of gaseous CO_(2),which could promote glucose conversion through the succinic acid path.To further increase gaseous CO_(2)fixation and succinic acid production and selectivity,stepwise CO_(2)addition was evaluated.50%-65%increase in inorganic carbon utilization was obtained coupled with 20%-30%increase in succinic acid selectivity.This was due to the promotion of the succinic acid branch of the glucose metabolism,while suppressing the pyruvate branch,along with the inhibition on the conversion from glucose to lactic acid.
基金the National Natural Science Foundation of China(grant No.U22A20434)the Foundation from Qinghai Science and Technology Department(grant No.2022-ZJ-706).
文摘The homogeneous and controllable morphology of anhydrous magnesium carbonate(MgCO_(3))particles with excellent properties is difficult to obtain because of a variety of synthetic factors.The effect of succinic acid as a crystal modifier on the particle morphology transformation of anhydrous MgCO_(3)was investigated by the hydrothermal method.The effect of the addition of succinic acid on the particles was similar to that of temperature change.The morphology of particles with a folded diamond-like shape was gradually uniform,and the particle size was between 3.3 and 7.5μm.Anhydrous MgCO_(3)particles prepared at pH 9 could easily agglomerate,and the average particle size increased from diamond-like to cube-like as the reaction time increased.The interaction between succinic acid and magnesium ions at different concentrations was the main factor responsible for the morphological changes.The pH,temperature,and time affected the molecular motion rate and crystal growth.
基金support from National Key R&D Program of China(2023YFA1507500)and DICP.
文摘Employing biodegradable plastics is one of the choices to solve white pollution issues.Polybutylene succinate(PBS),as a biodegradable plastic with good stability and heat resistance,is produced by polymerization of succinic acid and butylene glycol.However,inadequate supply of the direct upstream material succinic acid restricts the development of this industry.In this work,we provide a carbonylative strategy to construct succinic acid derivatives from carbon monoxide(CO),ethylene and alcohols.The reaction catalyzed by palladium catalyst under oxidative conditions.
基金The authors wish to acknowledge the Nebraska Corn Board for funding this work under award number 88-R-1718-01the financial support of the University of Nebraska-Lincoln Agricultural Research Division.
文摘Succinic acid is one of the most useful intermediate chemicals that can be produced in a biorefinery approach.In this study,Actinobacillus succinogenes was immobilized to produce succinic acid using non-detoxified corn fiber hydrolysate(CFH)and a control mimicking the sugars in CFH.Tests were carried out in a hollow fiber membrane packed-bed biofilm reactor(HFM–PBR)operated in a continuous mode.Under steady-state conditions,the bioconversion process was characterized in terms of sugar consumption,succinic acid and other organic acid production.Steady states were obtained at dilution rates of 0.025,0.05,0.075,0.1,0.2,and 0.3 h^(-1).The optimal results were achieved at the dilution rate of 0.05 h^(-1)and recirculation rate of 50 ml/min with a maximum succinic acid concentration,yield and productivity of 31.1 g/L,0.61 g/g and 1.56 g/L h,respectively,when control was used.Succinic acid concentration,yield and productivity of 23.4 g/L,0.51 g/g and 1.17 g/L h,respectively,were obtained when CFH was used.Productivity in the HFM–PBR was between 1.3 and 1.9 times higher than productivities for succinic acid production from CFH stated in the literature.The results demonstrated that immobilized A.succinogenes has the potential for effective conversion of an inexpensive biomass feedstock to succinic acid.Furthermore,the process has the potential to serve as a means for value-added chemical biomanufacturing in an integrated corn biorefinery.
基金supported by the National Major Special Project on New Varieties Cultivation for Transgenic Organisms(No.2009ZX08009-130B)the National Natural Science Foundation of China(No.50874112)the National High-Tech R&D Program(863)of China(No.2009AA06Z320)
文摘Succinic acid is considered as an important platform chemical. Succinic acid fermentation with Actinobacillus succinogenes strain BE-1 was optimized by central composite design (CCD) using a response surface methodology (RSM). The optimized production of succinic acid was predicted and the interactive effects between glucose, yeast extract, and magnesium carbonate were investigated. As a result, a model for predicting the concentration of succinic acid production was developed. The accuracy of the model was confirmed by the analysis of variance (ANOVA), and the validity was further proved by verification experiments showing that percentage errors between actual and predicted values varied from 3.02% to 6.38%. In addition, it was observed that the interactive effect between yeast extract and magnesium carbonate was statistically significant. In conclusion, RSM is an effective and useful method for optimizing the medium components and investigating the interactive effects, and can provide valuable information for succinic acid scale-up fermentation using A. succinogenes strain BE-I.
基金Supported by the National Natural Science Foundation of China (No. 29836130).
文摘Extraction equilibrium features of succinic acid, malic acid,maleic acid and fumaric acid were investi- gated systematically withtrioctylamine (TOA) in chloroform, 4-methyl-2-pentanone (MIBK) and1-octanol. Fourier transform-infrared (FTIR) spectroscopic analysisof organic samples loaded with the acid shows that amine forms 1:1complex of ion-pair association with succinic acid, malic acid andmaleic acid, and 1:1, 2:1 complex of ion-pair association withfumaric acid. It is proposed that the complex forms depend on thesecond dissociation constant of the dibasic acid, pK_a2.
基金the National High Technology Research and Development Program of China(Grant No.2006AA10Z326)the National Natural Science Foundation of China(Grant No.20676044)for their financial support.
文摘The effect of succinic acid deamidationinduced modification on wheat gluten was investigated in the present study.The changes of surface hydrophobicity,functional properties,secondary structure,and sensibility of proteolysis of modified samples were determined.The solubility of deamidated proteins increased in the isoelectric region of untreated wheat gluten.The isoelectric point of succinic acid deamidated wheat gluten was shifted to a basic pH and existed in the broad pH regions.Foaming property and molecular flexibility of wheat gluten were improved after the modification.The hydrolysis degree of the hydrolysates in proteolysis with flavorzyme and pancreatin increased after succinic acid deamidation.Moreover,succinic acid deamidation-induced modification resulted in little change in molecular weight and secondary structure of the protein.Thus,succinic acid could facilitate unfolding protein conformation.In addition,it could improve protein-water interactions,surface properties,and sensibility of the proteolysis of the deamidated wheat gluten.
文摘The underlying pathophysiology of liver dysfunction in urea cycle disorders(UCDs) is still largely elusive. There is some evidence that the accumulation of urea cycle(UC) intermediates are toxic for hepatocyte mitochondria. It is possible that liver injury is directly caused by the toxicity of ammonia. The rarity of UCDs, the lack of checking of iron level in these patients, superficial knowledge of UC and an underestimation of the metabolic role of fumaric acid, are the main reasons that are responsible for the incomprehension of the mechanism of liver injury in patients suffering from UCDs. Owing to our routine clinical practice to screen for iron overload in severely ill neonates, with the focus on the newborns suffering from acute liver failure, we report a case of citrullinemia with neonatal liver failure and high blood parameters of iron overload. We hypothesize that the key is in the decreased-deficient fumaric acid production in the course of UC in UCDs that causes several sequentially intertwined metabolic disturbances with final result of liver iron overload. The presented hypothesis could be easily tested by examining the patients suffering from UCDs, for liver iron overload. This could be easily performed in countries with a high population and comprehensive national register for inborn errors of metabolism. Conclusion: Providing the hypothesis is correct, neonatal liver damage in patients having UCD can be prevented by the supplementation of pregnant women with fumaric or succinic acid, prepared in the form of iron supplementation pills. After birth, liverdamage in patients having UCDs can be prevented by supplementation of these patients with zinc fumarate or zinc succinylate, as well.
基金supported by National High-tech Research and Development Projects (863): the key technology of efficient exploiting deep brine in the Yellow River delta (Contracts 2012AA061705)
文摘Now the mining of high salt underground brine has been an important aspect of salt lake mining,which is the necessary support to the development of national economy.With the change of underground geological
基金The authors are grateful for the fnancial support from the National First-class Discipline Program of Light Industry Technology and Engineering(Grant No.LITE2018-04)the Topnotch Academic Programs Project of Jiangsu Higher Education Institutions(TAPP).
文摘The glutamate decarboxylase(Gad)system is an important amino acid-dependent acid resistance system commonly found in microorganisms.Actinobacillus succinogenes is one of the best natural producers of succinic acid(SA)but lacks glutamate decarboxylase.This study assessed the efects of Gad system introduction into A.succinogenes.The recombinant strains gadB-SW and gadBC-SW were constructed by heterologous expression of gadB alone,or gadB together with gadC,respectively.After 1.0 and 1.5 h of acid stress at pH 4.6,cell survival of gadBC-SW was greater than gadB-SW.The growth of gadB-SW and gadBC-SW was both afected by the expression of heterologous proteins and byγ-aminobutyric acid,with gadBC-SW growth reduced at a neutral pH.SA production in acidic conditions was evaluated by a shake fask and by 3-L bioreactor fermentation.The results showed gadBC-SW to increase SA production by 8.4%in shake fask compared to the parent strain,SW.For a 3-L bioreactor batch fermentation under acidic environment,the highest conversion rate of sugar to SA was observed for gadBC-SW,reaching 96%.However,SA concentration by gadBC-SW was only 47 g/L and 31 g/L at pH 6.5 and pH 6.0,respectively.In summary,the introduction of heterologous gadB and gadC into A.succinogenes not only improved acid tolerance but also infuenced the synthesis of SA and added a metabolic burden.