The objectives of this study were to evaluate the effect of hexanoic acid(HA)supplementations(0,as the control,CON;0.05%,HA1;0.1%,HA2;0.2%,HA3)onβ-carotene,and ascertain the way and key factors of HA influencingβ-ca...The objectives of this study were to evaluate the effect of hexanoic acid(HA)supplementations(0,as the control,CON;0.05%,HA1;0.1%,HA2;0.2%,HA3)onβ-carotene,and ascertain the way and key factors of HA influencingβ-carotene content of alfalfa(Medicago sativa L.)after ensiled in an oxygen-free and dark conditions for 10,40,and 80 d(from May to August,2021).This was achieved by examining the dynamic change ofβ-carotene,activities ofβ-carotenerelated enzymes,and bacterial community succession of ensiled alfalfa,using operon crtNM identification,crtE gene quantitation,and single-molecule real-time sequencing technology.The results revealed that when compared with the fresh material,terminal alfalfa silage treated with different level of HA supplementations(0,0.05,0.1,0.2%;fresh weight basis)increasedβ-carotene content up to 2.86,85.8,159,and 133%,accordingly.Meanwhile,alfalfa silage treated with higher levels of HA(0.1 and 0.2%)showed superior effects compared to those treated with lower levels of supplementation(0 and 0.05%).HA supplementation specifically facilitated the increase abundance of Lactobacillus kullabergensis and the emergence of L.senioris.Multiple linear regression models inferred that L.kullabergensis,L.apis,L.saniviri,L.senioris,peroxidase,phytoene desaturase,and lycopeneβ-cyclase positively regulatedβ-carotene.Conversely,Lactobacillus rennini and L.brevis adjustedβ-carotene,negatively.Positive regulations of the above bacterial species and enzymes had a stronger role in increasingβ-carotene than L.rennini and L.brevis.In conclusion,theβ-carotene increase of ensiled alfalfa may be regulated by HA supplementation via multiple positive factors,including 4 special Lactobacillus species(L.kullabergensis,L.apis,L.saniviri,and L.senioris),and 3 vegetativeβ-carotene-related enzymes(peroxidase,phytoene desaturase,and lycopeneβ-cyclase).展开更多
The highly dispersed Pt-ReOx （x _〈 1 ） sites ca. 0.5 nm in size were formed via a successive and strong inter- action of the Re precursor with titania and then of the Pt complex with deposited low-valent rhenium ox...The highly dispersed Pt-ReOx （x _〈 1 ） sites ca. 0.5 nm in size were formed via a successive and strong inter- action of the Re precursor with titania and then of the Pt complex with deposited low-valent rhenium oxide clusters. The size, charge and chemical composition were characterized by means of HRTEM/STEM with EDX mapping, XPS, and FTIRS. These sites with Re/Pt = 2 were shown to be highly active and selective in the hydrogenation of carboxylic acid to alcohol under very mild conditions （T = 130 ℃, P = 50 bar）. The reaction rate constant for the hydrogenation of hexanoic acid increased linearly with the Pt content. As for the homogeneous pincer-type Ru-organic complexes, the active Pt-ReOx sites can dissociate heterolytically the molecular hydrogen with the formation of hydroxyl groups and Pt hydride for hydrogenation of the carboxylic group. Indeed, TOF of 20 h 1 and selectivity of 98%-99% are approaching the values typical of homogeneous catalysts. The first order kinetics described well the experimental data obtained in a wide range of reaction conditions.展开更多
Hexanoic acid (HX) is a crucial flavor compound and precursor of ethyl caproate (EA), which determines the quality of Chinese Luzhou-flavor liquor (CLFL). The isolation, purification, identification, and optimization ...Hexanoic acid (HX) is a crucial flavor compound and precursor of ethyl caproate (EA), which determines the quality of Chinese Luzhou-flavor liquor (CLFL). The isolation, purification, identification, and optimization of fermentation conditions of HX-producing bacteria are essential for industrial CLFL production. In this study, one strain of HX-producing bacterium was isolated from six candidate bacterial strains and identified as Clostridium sartagoneforme. Then, the growth characteristics and HX production of C. sartagoneforme were investigated. Sodium acetate medium was identified as the optimal fermentation medium from four candidate media. C. sartagoneforme yielded 800.85 ± 12.87 mg/100mL HX in sodium acetate medium. Then, to further optimize the formula of the fermentation medium, the carbon and nitrogen sources and inorganic salt component of the fermentation medium were investigated using HX yields as an optimization index. Optimization was performed with a single-factor experiment and the Taguchi design method. The single-factor experiment showed that the highest HX outputs were obtained when the sodium acetate medium contained 2.5 g/L yeast extract, 1.8 g/L KCl, 20 g/L sodium acetate, 15 mL/L ethanol, and 1.5 g/L glucose. In the orthogonal experiment designed using the Taguchi design method, HX yields reached 2018.29 ± 46.37 mg/100mL in sodium acetate medium that contained 3.5 g/L yeast extract, 1.8 g/L KCl, 25 g/L sodium acetate, and 15 mL/L ethanol.展开更多
Medium-chain fatty acids (MCFA) are straight-chain fatty acids with aliphatic tails of 6 - 12 carbons, which can form medium-chain triglycerides. They are found mostly in animal fats and in the tropical vegetable oils...Medium-chain fatty acids (MCFA) are straight-chain fatty acids with aliphatic tails of 6 - 12 carbons, which can form medium-chain triglycerides. They are found mostly in animal fats and in the tropical vegetable oils. Because of their wide applications in industry, there is a growing demand of esters of medium-chain fatty acids production. The aim of our work was investigations of the kinetics of the synthesis of esters of MCFA in the presence of dowex catalyst in wide range of process parameters. Hexanoic, octanoic and decanoic acids were esterified with n-octyl alcohol in the presence of sulfuric acid and commercial dowex W50X8 as catalysts in an experimental semi-periodic glass tank reactor with instantaneous and complete water removal. Because of complete removal of water from the reacting mixture, thus eliminating the reverse hydrolysis reaction, the esterification can be assumed as irreversible reaction. The temperature range was 393 - 423 K, the range of initial mole ratio of alcohol to acid was 3 - 10. The kinetic parameters are given. The reaction kinetics appeared to be of the first order with respect to the acid. The effect of temperature on the reaction rate follows the Arrhenius equation well.展开更多
In China, great efforts are being made to remediate farmlands polluted by heavy metals. In this study, a soil pot experiment was conducted to examine the effects of a new-type cleaning agent, methylglycinediacetic aci...In China, great efforts are being made to remediate farmlands polluted by heavy metals. In this study, a soil pot experiment was conducted to examine the effects of a new-type cleaning agent, methylglycinediacetic acid(MGDA), and a plant growth regulator(PGR), diethl aminoethyl hexanoate(DA-6), on plant growth and extraction and detoxification of cadmium(Cd) by ryegrass. The results showed that foliar spray of DA-6 alone improved plant growth, with root length and shoot dry biomass increased by 38.5%–58.6% and 71.1%–89.3%, respectively, whereas addition of MGDA alone decreased root length and shoot dry biomass by 10.3%–18.6%and 9.1%–21.8%, respectively. Diethl aminoethyl hexanoate promoted the binding of Cd to cell walls and thus alleviated the toxicity of Cd and/or MGDA to plants. Applications of DA-6 and/or MGDA resulted in a significant increase in Cd extraction efficiency(P < 0.05), and the efficiency decreased in the order of MGDA + DA-6 > DA-6 > MGDA. The treatment of MGDA + DA-6 achieved 2.2%, 1.7%, and 0.8% Cd extraction efficiency by ryegrass in soils spiked with 25, 50, 100 mg Cd kg^(-1), respectively. Therefore,treatment of MGDA + DA-6 could be an efficient method for enhancing phytoremediation of Cd-contaminated soil by ryegrass.展开更多
Racemic 2-n-butylbutanedioic acid 4-t-butyl esters were synthesized from methyl hexanoate and t-butyl α-iodoacetate via alkylation and subsequently selective hydrolyzation. The （R）-and （S）-2-n-butylbutanedioic ac...Racemic 2-n-butylbutanedioic acid 4-t-butyl esters were synthesized from methyl hexanoate and t-butyl α-iodoacetate via alkylation and subsequently selective hydrolyzation. The （R）-and （S）-2-n-butylbutanedioic acid 4-t-butyl esters were obtained by the resolution of the above-mentioned racemic compounds with（S）-（ - ） or（R）-（ ＋ ）-α- methylbenzylamine, respectively. The e.e. values of the two optical active products were determined to be above 99% by HPLC after the formation of two pairs of diastereoisomers with（R）-（ ＋ ）-α-methylbenzylamine and（S）- phenylalanine methyl ester.展开更多
Field efficacy trials showed that Diethy Amioethyl Hexanoate 5% AS could promote growth and increase yield of cabbage. The cabbage yield increase rate was up to 40.37% by using reagent dilution 2 000 -2 500 times twic...Field efficacy trials showed that Diethy Amioethyl Hexanoate 5% AS could promote growth and increase yield of cabbage. The cabbage yield increase rate was up to 40.37% by using reagent dilution 2 000 -2 500 times twice, so Diethy Diethy Amioethyl Hexanoate 5% AS is an ideal agent for regulating cabbage growth and increasing yield.展开更多
This study was conducted to extract scarce natural liquor flavorings desired by many liquor factories from yellow water. Five straight-chain saturated fatty acids were firstly extracted from 15 fractions of yellow wat...This study was conducted to extract scarce natural liquor flavorings desired by many liquor factories from yellow water. Five straight-chain saturated fatty acids were firstly extracted from 15 fractions of yellow water, forming 1 fraction of the ethanol solution composed of the mixture of the five straight-chain saturated fatty acids. Then, 100 fractions of the ethanol solution could produce 94.857 6 fractions of esterification liquid through catalytic esterification at 80 ℃. The esterification liquid contains five esters： ethyl acetate, ethyl propionate, ethyl butyrate, ethyl valerate and ethyl caproate, with contents of 17.68%, 2.58%, 6.32%, 0.06% and 19.40%, respectively. The esterification liquid prepared from 1 fraction of yellow water could blend 10.54 fractions of white liquor into top-grade Luzhou-flavor liquor after esterification. It indicates that yellow water has very good recycling and utilization value.展开更多
Ethyl hexanoate is the pivotal aroma compound in strong-flavor Baijiu;however,its inconsistent yield during fermentation remains a major challenge for batch consistency.Targeted co-culture of functionally complementar...Ethyl hexanoate is the pivotal aroma compound in strong-flavor Baijiu;however,its inconsistent yield during fermentation remains a major challenge for batch consistency.Targeted co-culture of functionally complementary microorganisms represents a promising strategy to enhance both the stability and quality of strong-flavor Baijiu.In this study,Saccharomyces cerevisiae DQ-8(ethanol producer)and Clostridium kluyveri DSM 555(hexanoic acid producer)were co-cultured in a solid-state simulated fermentation system.The results indicated that ethanol produced by S.cerevisiae DQ-8 served as an electron donor to support the growth and metabolism of C.kluyveri DSM 555,while butyric acid generated by C.kluyveri DSM 555 was elongated to form hexanoic acid.The subsequent esterification of ethanol and hexanoic acid in the co-culture system efficiently produced ethyl hexanoate.In solid-state fermentation,the co-culture group(SC)exhibited a 321.90% increase in ethyl hexanoate yield compared to the control group(CK),and the effect was significantly stronger than that of the singlestrain fortification groups(S and C).Furthermore,the group SC achieved a more balanced flavor profile,with optimized ratios of key esters.High-throughput sequencing indicated the formation of a stable microbial con-sortium dominated by Saccharomyces,Pediococcus,and Clostridium,which enhanced starch utilization,moderated acidity,and promoted ester diversity.Therefore,this study demonstrates that targeted co-culture of complementary microorganisms not only enhances ethyl hexanoate production but also stabilizes the overall flavor profile,offering a theoretical foundation for improving batch consistency in strong-flavor Baijiu fermentation.展开更多
Because of its therapeutic and health-promoting properties,Crataegus has substantial commercial value.Flavonoids are the main functional ingredients of hawthorn fruits.The nutritional value and quality of hawthorn fru...Because of its therapeutic and health-promoting properties,Crataegus has substantial commercial value.Flavonoids are the main functional ingredients of hawthorn fruits.The nutritional value and quality of hawthorn fruit are greatly enhanced by increasing its flavonoid content.The plant growth regulator diethylaminoethyl hexanoate(DA-6)has shown potential in this regard;however,little is known about its effects on hawthorn fruit quality,particularly flavonoid biosynthesis.This study investigated the transcriptome and metabolome of hawthorn fruit treated with DA-6.The results showed that by stimulating the activities of key synthases,treatment with 10 mg/L DA-6 increased flavonoid and anthocyanin contents.In total,22 differentially accumulated flavonoid metabolites and 21 differentially expressed genes were identified.Key potential transcription factors associated with flavonoid biosynthesis,including MYB5,NAC82,b HLH62,ABI5,and WRKY44,were identified using the co-expression networks.Additionally,genetic and metabolic regulatory networks of flavonoid biosynthesis were proposed based on the differentially accumulated flavonoid metabolites and crucial genes.Overall,this study offers valuable insights for future research on the intricate molecular networks of flavonoid biosynthesis activated by the plant growth regulator DA-6.展开更多
Biofortification of Baijiu fermentation using exogenous functional strains can change the microbial community structure of the fermentation ecosystem and flavor metabolism,which can impact Baijiu flavor.In this work,a...Biofortification of Baijiu fermentation using exogenous functional strains can change the microbial community structure of the fermentation ecosystem and flavor metabolism,which can impact Baijiu flavor.In this work,a high ethyl hexanoate-producing Saccharomyces cerevisiae Y285 strain was added for biofortification to investigate microbial communities’succession and flavor compounds throughout the fermentation of strong-flavor Baijiu.The microbial community composition of the fermentation samples was analyzed using the Illumina MiSeq platform,and the results showed that Pediococcus,Lactobacillus,Weissella and Saccharomyces were the dominant genera.A total of 111 flavor compounds,consisting of esters(50),alcohols(14),acids(3),aldehydes(9),phenols(9),pyrazines(3),ketones(8),and others(15),were detected in all samples,and the content of total esters of the fortified Daqu increased dramatically.Among them,the content of ethyl acetate decreased while that of ethyl hexanoate increased significantly,and the content of other compounds such as ethyl palmitate,ethanol,phenethyl alcohol and tetramethylpyrazine also increased.Redundancy analysis and Spearman’s correlation analysis revealed that Saccharomyces,Pediococcus,Lactobacillus,and Weissella were significantly positively correlated with esters and alcohols.To summarize,biofortification with S.cerevisiae during Baijiu fermentation modifies microbial community composition,as well as the content of ethyl hexanoate in Baijiu,and induces changes in the content of other flavor compounds.These findings imply that modifying the microorganisms throughout the Baijiu fermentation process can alter the flavor of Baijiu and further enhance it.展开更多
Diethyl aminoethyl hexanoate AC is a new-style growth hormone that induces cuttings to root by molecule signal. With Eucalptus urophylla and E. urophyllaxE, grandis as testing varieties, effects of applying different ...Diethyl aminoethyl hexanoate AC is a new-style growth hormone that induces cuttings to root by molecule signal. With Eucalptus urophylla and E. urophyllaxE, grandis as testing varieties, effects of applying different growth hormones on eucalypt cuttage were compared through experiments, and the result showed that diethyl aminoethyl hexanoate AC made cuttings root 4 days earlier than other common growth hormones did. The average rooting rate and the mean root quantity of diethyl aminoethyl hexanoate AC treated cuttings were 11%-26.5% higher than and 1.8-8.5 pieces per cutting more than those in other treatments. Besides, the seedlings were excellent. The new-style growth hormone improves cuttage of eucalypt to a higher level.展开更多
The purpose of this study was to investigate in vitro biocompatibility of a new type of polymer, polyhydroxybutyrate co hexanoate (PHBHHx). The hydrophilicity and biocompatibility were studied with two kinds of enzy...The purpose of this study was to investigate in vitro biocompatibility of a new type of polymer, polyhydroxybutyrate co hexanoate (PHBHHx). The hydrophilicity and biocompatibility were studied with two kinds of enzymes, amylase BAN480L and lipase Novozym388. The degree of hydrophilicity was observed using contact angle measurements. In vitro biocompatibility evaluations were carried out by direct incubation of mouse fibroblast cell line L929 on the polyhydroxyalkanoate (PHA) films. The samples treated with BAN480L showed that the PHA biocompatibility increased while the hydrophilicity decreased. Relative to untreated samples, the number of cells on the Novozym388 modified PHBHHx significant decrease as the hydrophilicity also decreased. The results indicated that other surface characteristics besides hydrophilicity influence the biocompatibility of PHBHHx films.展开更多
Targeted biofortification is an effective way to regulate the microbial community succession and the production of flavor metabolites in the Baijiu fermentation.However,the high organic acid present in the Baijiu brew...Targeted biofortification is an effective way to regulate the microbial community succession and the production of flavor metabolites in the Baijiu fermentation.However,the high organic acid present in the Baijiu brewing process causes the gradual succession of exogenous functional microorganisms to be less dominant,ultimately resulting in defective flavor substances.In this study,a strain of Saccharomyces cerevisiae YS219 with high production of ethyl hexanoate and excellent organic acid tolerance was excavated,and the effects of this strain on the microbial composition and flavor metabolites during the fermentation of strong-flavor Baijiu were investigated.The microbial community was analyzed using the Illumina Miseq Pe300 Sequencing Platform,and at the genus level,Saccharomyces,Lactobacillus,and Pediococcus became the dominant genera after biofortification.A total of 77 flavor substances were detected in the biofortified fermented grains,and the contents of total esters and alcohols increased significantly.Among them,ethanol and ethyl hexanoate were significantly increased.Mantel test showed significant positive correlation between lactic acid and Pediococcus.Moreover,lactic acid,acetic acid,and ethanol were negatively correlated with most of the fermenting microorganisms.Following inoculation with S.cerevisiae YS219,Saccharomyces and Pediococcus exhibited a positively significant link with ethyl hexanoate,according to Spearman’s correlation analysis.Taken together,the results demonstrate that the addition of S.cerevisiae with excellent organic acid tolerance and high ethyl hexanoate production helps to promote the change of microbial community and the elevation of ethanol and ethyl hexanoate.展开更多
基金supported by the National Natural Science Foundation of China(31971765)the Fundamental Research Funds for the Central Universities,China(KYYZ2023002)+2 种基金the Anhui Province International Joint Research Center of Forage Bio-breeding,China(AHIJRCFB202305)the Key Research and Development Projects of Hainan Province,China(ZDYF2022XDNY153)the Fundamental Research Funds for the Central Universities,China(XUEKEN2022020)。
文摘The objectives of this study were to evaluate the effect of hexanoic acid(HA)supplementations(0,as the control,CON;0.05%,HA1;0.1%,HA2;0.2%,HA3)onβ-carotene,and ascertain the way and key factors of HA influencingβ-carotene content of alfalfa(Medicago sativa L.)after ensiled in an oxygen-free and dark conditions for 10,40,and 80 d(from May to August,2021).This was achieved by examining the dynamic change ofβ-carotene,activities ofβ-carotenerelated enzymes,and bacterial community succession of ensiled alfalfa,using operon crtNM identification,crtE gene quantitation,and single-molecule real-time sequencing technology.The results revealed that when compared with the fresh material,terminal alfalfa silage treated with different level of HA supplementations(0,0.05,0.1,0.2%;fresh weight basis)increasedβ-carotene content up to 2.86,85.8,159,and 133%,accordingly.Meanwhile,alfalfa silage treated with higher levels of HA(0.1 and 0.2%)showed superior effects compared to those treated with lower levels of supplementation(0 and 0.05%).HA supplementation specifically facilitated the increase abundance of Lactobacillus kullabergensis and the emergence of L.senioris.Multiple linear regression models inferred that L.kullabergensis,L.apis,L.saniviri,L.senioris,peroxidase,phytoene desaturase,and lycopeneβ-cyclase positively regulatedβ-carotene.Conversely,Lactobacillus rennini and L.brevis adjustedβ-carotene,negatively.Positive regulations of the above bacterial species and enzymes had a stronger role in increasingβ-carotene than L.rennini and L.brevis.In conclusion,theβ-carotene increase of ensiled alfalfa may be regulated by HA supplementation via multiple positive factors,including 4 special Lactobacillus species(L.kullabergensis,L.apis,L.saniviri,and L.senioris),and 3 vegetativeβ-carotene-related enzymes(peroxidase,phytoene desaturase,and lycopeneβ-cyclase).
文摘The highly dispersed Pt-ReOx （x _〈 1 ） sites ca. 0.5 nm in size were formed via a successive and strong inter- action of the Re precursor with titania and then of the Pt complex with deposited low-valent rhenium oxide clusters. The size, charge and chemical composition were characterized by means of HRTEM/STEM with EDX mapping, XPS, and FTIRS. These sites with Re/Pt = 2 were shown to be highly active and selective in the hydrogenation of carboxylic acid to alcohol under very mild conditions （T = 130 ℃, P = 50 bar）. The reaction rate constant for the hydrogenation of hexanoic acid increased linearly with the Pt content. As for the homogeneous pincer-type Ru-organic complexes, the active Pt-ReOx sites can dissociate heterolytically the molecular hydrogen with the formation of hydroxyl groups and Pt hydride for hydrogenation of the carboxylic group. Indeed, TOF of 20 h 1 and selectivity of 98%-99% are approaching the values typical of homogeneous catalysts. The first order kinetics described well the experimental data obtained in a wide range of reaction conditions.
文摘Hexanoic acid (HX) is a crucial flavor compound and precursor of ethyl caproate (EA), which determines the quality of Chinese Luzhou-flavor liquor (CLFL). The isolation, purification, identification, and optimization of fermentation conditions of HX-producing bacteria are essential for industrial CLFL production. In this study, one strain of HX-producing bacterium was isolated from six candidate bacterial strains and identified as Clostridium sartagoneforme. Then, the growth characteristics and HX production of C. sartagoneforme were investigated. Sodium acetate medium was identified as the optimal fermentation medium from four candidate media. C. sartagoneforme yielded 800.85 ± 12.87 mg/100mL HX in sodium acetate medium. Then, to further optimize the formula of the fermentation medium, the carbon and nitrogen sources and inorganic salt component of the fermentation medium were investigated using HX yields as an optimization index. Optimization was performed with a single-factor experiment and the Taguchi design method. The single-factor experiment showed that the highest HX outputs were obtained when the sodium acetate medium contained 2.5 g/L yeast extract, 1.8 g/L KCl, 20 g/L sodium acetate, 15 mL/L ethanol, and 1.5 g/L glucose. In the orthogonal experiment designed using the Taguchi design method, HX yields reached 2018.29 ± 46.37 mg/100mL in sodium acetate medium that contained 3.5 g/L yeast extract, 1.8 g/L KCl, 25 g/L sodium acetate, and 15 mL/L ethanol.
文摘Medium-chain fatty acids (MCFA) are straight-chain fatty acids with aliphatic tails of 6 - 12 carbons, which can form medium-chain triglycerides. They are found mostly in animal fats and in the tropical vegetable oils. Because of their wide applications in industry, there is a growing demand of esters of medium-chain fatty acids production. The aim of our work was investigations of the kinetics of the synthesis of esters of MCFA in the presence of dowex catalyst in wide range of process parameters. Hexanoic, octanoic and decanoic acids were esterified with n-octyl alcohol in the presence of sulfuric acid and commercial dowex W50X8 as catalysts in an experimental semi-periodic glass tank reactor with instantaneous and complete water removal. Because of complete removal of water from the reacting mixture, thus eliminating the reverse hydrolysis reaction, the esterification can be assumed as irreversible reaction. The temperature range was 393 - 423 K, the range of initial mole ratio of alcohol to acid was 3 - 10. The kinetic parameters are given. The reaction kinetics appeared to be of the first order with respect to the acid. The effect of temperature on the reaction rate follows the Arrhenius equation well.
基金supported by the National Natural Science Foundation of China (Nos. 41501521 and 41301327)
文摘In China, great efforts are being made to remediate farmlands polluted by heavy metals. In this study, a soil pot experiment was conducted to examine the effects of a new-type cleaning agent, methylglycinediacetic acid(MGDA), and a plant growth regulator(PGR), diethl aminoethyl hexanoate(DA-6), on plant growth and extraction and detoxification of cadmium(Cd) by ryegrass. The results showed that foliar spray of DA-6 alone improved plant growth, with root length and shoot dry biomass increased by 38.5%–58.6% and 71.1%–89.3%, respectively, whereas addition of MGDA alone decreased root length and shoot dry biomass by 10.3%–18.6%and 9.1%–21.8%, respectively. Diethl aminoethyl hexanoate promoted the binding of Cd to cell walls and thus alleviated the toxicity of Cd and/or MGDA to plants. Applications of DA-6 and/or MGDA resulted in a significant increase in Cd extraction efficiency(P < 0.05), and the efficiency decreased in the order of MGDA + DA-6 > DA-6 > MGDA. The treatment of MGDA + DA-6 achieved 2.2%, 1.7%, and 0.8% Cd extraction efficiency by ryegrass in soils spiked with 25, 50, 100 mg Cd kg^(-1), respectively. Therefore,treatment of MGDA + DA-6 could be an efficient method for enhancing phytoremediation of Cd-contaminated soil by ryegrass.
基金Supported by the National Basic Research Priority Program(No. 2003CCA027).
文摘Racemic 2-n-butylbutanedioic acid 4-t-butyl esters were synthesized from methyl hexanoate and t-butyl α-iodoacetate via alkylation and subsequently selective hydrolyzation. The （R）-and （S）-2-n-butylbutanedioic acid 4-t-butyl esters were obtained by the resolution of the above-mentioned racemic compounds with（S）-（ - ） or（R）-（ ＋ ）-α- methylbenzylamine, respectively. The e.e. values of the two optical active products were determined to be above 99% by HPLC after the formation of two pairs of diastereoisomers with（R）-（ ＋ ）-α-methylbenzylamine and（S）- phenylalanine methyl ester.
文摘Field efficacy trials showed that Diethy Amioethyl Hexanoate 5% AS could promote growth and increase yield of cabbage. The cabbage yield increase rate was up to 40.37% by using reagent dilution 2 000 -2 500 times twice, so Diethy Diethy Amioethyl Hexanoate 5% AS is an ideal agent for regulating cabbage growth and increasing yield.
基金Supported by Shandong Province Key Research and Development Planning Project(No.2017GSF2160092017GGX10136)
文摘This study was conducted to extract scarce natural liquor flavorings desired by many liquor factories from yellow water. Five straight-chain saturated fatty acids were firstly extracted from 15 fractions of yellow water, forming 1 fraction of the ethanol solution composed of the mixture of the five straight-chain saturated fatty acids. Then, 100 fractions of the ethanol solution could produce 94.857 6 fractions of esterification liquid through catalytic esterification at 80 ℃. The esterification liquid contains five esters： ethyl acetate, ethyl propionate, ethyl butyrate, ethyl valerate and ethyl caproate, with contents of 17.68%, 2.58%, 6.32%, 0.06% and 19.40%, respectively. The esterification liquid prepared from 1 fraction of yellow water could blend 10.54 fractions of white liquor into top-grade Luzhou-flavor liquor after esterification. It indicates that yellow water has very good recycling and utilization value.
基金supported by the National Key Research and Development Program of China,(grant number 2022YFD2101401).
文摘Ethyl hexanoate is the pivotal aroma compound in strong-flavor Baijiu;however,its inconsistent yield during fermentation remains a major challenge for batch consistency.Targeted co-culture of functionally complementary microorganisms represents a promising strategy to enhance both the stability and quality of strong-flavor Baijiu.In this study,Saccharomyces cerevisiae DQ-8(ethanol producer)and Clostridium kluyveri DSM 555(hexanoic acid producer)were co-cultured in a solid-state simulated fermentation system.The results indicated that ethanol produced by S.cerevisiae DQ-8 served as an electron donor to support the growth and metabolism of C.kluyveri DSM 555,while butyric acid generated by C.kluyveri DSM 555 was elongated to form hexanoic acid.The subsequent esterification of ethanol and hexanoic acid in the co-culture system efficiently produced ethyl hexanoate.In solid-state fermentation,the co-culture group(SC)exhibited a 321.90% increase in ethyl hexanoate yield compared to the control group(CK),and the effect was significantly stronger than that of the singlestrain fortification groups(S and C).Furthermore,the group SC achieved a more balanced flavor profile,with optimized ratios of key esters.High-throughput sequencing indicated the formation of a stable microbial con-sortium dominated by Saccharomyces,Pediococcus,and Clostridium,which enhanced starch utilization,moderated acidity,and promoted ester diversity.Therefore,this study demonstrates that targeted co-culture of complementary microorganisms not only enhances ethyl hexanoate production but also stabilizes the overall flavor profile,offering a theoretical foundation for improving batch consistency in strong-flavor Baijiu fermentation.
基金supported by the China Postdoctoral Science Foundation(No.2024MD763998)the National Key Research and Development Program of China(No.2024YFD160060^(*))。
文摘Because of its therapeutic and health-promoting properties,Crataegus has substantial commercial value.Flavonoids are the main functional ingredients of hawthorn fruits.The nutritional value and quality of hawthorn fruit are greatly enhanced by increasing its flavonoid content.The plant growth regulator diethylaminoethyl hexanoate(DA-6)has shown potential in this regard;however,little is known about its effects on hawthorn fruit quality,particularly flavonoid biosynthesis.This study investigated the transcriptome and metabolome of hawthorn fruit treated with DA-6.The results showed that by stimulating the activities of key synthases,treatment with 10 mg/L DA-6 increased flavonoid and anthocyanin contents.In total,22 differentially accumulated flavonoid metabolites and 21 differentially expressed genes were identified.Key potential transcription factors associated with flavonoid biosynthesis,including MYB5,NAC82,b HLH62,ABI5,and WRKY44,were identified using the co-expression networks.Additionally,genetic and metabolic regulatory networks of flavonoid biosynthesis were proposed based on the differentially accumulated flavonoid metabolites and crucial genes.Overall,this study offers valuable insights for future research on the intricate molecular networks of flavonoid biosynthesis activated by the plant growth regulator DA-6.
基金the National Natural Science Foundation of China(31830069)the Beijing Municipal Natural Science Foundation&Beijing Municipal Education Commission(KZ202110011016).
文摘Biofortification of Baijiu fermentation using exogenous functional strains can change the microbial community structure of the fermentation ecosystem and flavor metabolism,which can impact Baijiu flavor.In this work,a high ethyl hexanoate-producing Saccharomyces cerevisiae Y285 strain was added for biofortification to investigate microbial communities’succession and flavor compounds throughout the fermentation of strong-flavor Baijiu.The microbial community composition of the fermentation samples was analyzed using the Illumina MiSeq platform,and the results showed that Pediococcus,Lactobacillus,Weissella and Saccharomyces were the dominant genera.A total of 111 flavor compounds,consisting of esters(50),alcohols(14),acids(3),aldehydes(9),phenols(9),pyrazines(3),ketones(8),and others(15),were detected in all samples,and the content of total esters of the fortified Daqu increased dramatically.Among them,the content of ethyl acetate decreased while that of ethyl hexanoate increased significantly,and the content of other compounds such as ethyl palmitate,ethanol,phenethyl alcohol and tetramethylpyrazine also increased.Redundancy analysis and Spearman’s correlation analysis revealed that Saccharomyces,Pediococcus,Lactobacillus,and Weissella were significantly positively correlated with esters and alcohols.To summarize,biofortification with S.cerevisiae during Baijiu fermentation modifies microbial community composition,as well as the content of ethyl hexanoate in Baijiu,and induces changes in the content of other flavor compounds.These findings imply that modifying the microorganisms throughout the Baijiu fermentation process can alter the flavor of Baijiu and further enhance it.
文摘Diethyl aminoethyl hexanoate AC is a new-style growth hormone that induces cuttings to root by molecule signal. With Eucalptus urophylla and E. urophyllaxE, grandis as testing varieties, effects of applying different growth hormones on eucalypt cuttage were compared through experiments, and the result showed that diethyl aminoethyl hexanoate AC made cuttings root 4 days earlier than other common growth hormones did. The average rooting rate and the mean root quantity of diethyl aminoethyl hexanoate AC treated cuttings were 11%-26.5% higher than and 1.8-8.5 pieces per cutting more than those in other treatments. Besides, the seedlings were excellent. The new-style growth hormone improves cuttage of eucalypt to a higher level.
文摘The purpose of this study was to investigate in vitro biocompatibility of a new type of polymer, polyhydroxybutyrate co hexanoate (PHBHHx). The hydrophilicity and biocompatibility were studied with two kinds of enzymes, amylase BAN480L and lipase Novozym388. The degree of hydrophilicity was observed using contact angle measurements. In vitro biocompatibility evaluations were carried out by direct incubation of mouse fibroblast cell line L929 on the polyhydroxyalkanoate (PHA) films. The samples treated with BAN480L showed that the PHA biocompatibility increased while the hydrophilicity decreased. Relative to untreated samples, the number of cells on the Novozym388 modified PHBHHx significant decrease as the hydrophilicity also decreased. The results indicated that other surface characteristics besides hydrophilicity influence the biocompatibility of PHBHHx films.
基金support obtained from the National Key Research and Development Program of China(2022YFD2101401).
文摘Targeted biofortification is an effective way to regulate the microbial community succession and the production of flavor metabolites in the Baijiu fermentation.However,the high organic acid present in the Baijiu brewing process causes the gradual succession of exogenous functional microorganisms to be less dominant,ultimately resulting in defective flavor substances.In this study,a strain of Saccharomyces cerevisiae YS219 with high production of ethyl hexanoate and excellent organic acid tolerance was excavated,and the effects of this strain on the microbial composition and flavor metabolites during the fermentation of strong-flavor Baijiu were investigated.The microbial community was analyzed using the Illumina Miseq Pe300 Sequencing Platform,and at the genus level,Saccharomyces,Lactobacillus,and Pediococcus became the dominant genera after biofortification.A total of 77 flavor substances were detected in the biofortified fermented grains,and the contents of total esters and alcohols increased significantly.Among them,ethanol and ethyl hexanoate were significantly increased.Mantel test showed significant positive correlation between lactic acid and Pediococcus.Moreover,lactic acid,acetic acid,and ethanol were negatively correlated with most of the fermenting microorganisms.Following inoculation with S.cerevisiae YS219,Saccharomyces and Pediococcus exhibited a positively significant link with ethyl hexanoate,according to Spearman’s correlation analysis.Taken together,the results demonstrate that the addition of S.cerevisiae with excellent organic acid tolerance and high ethyl hexanoate production helps to promote the change of microbial community and the elevation of ethanol and ethyl hexanoate.
