Chestnut tannin,extracted from the bark or wood of chestnut trees,possesses unique properties that make it valuable in various industries.It serves as a natural source of tannins,which are widely used in the productio...Chestnut tannin,extracted from the bark or wood of chestnut trees,possesses unique properties that make it valuable in various industries.It serves as a natural source of tannins,which are widely used in the production of leather,textiles,and wood preservation.As research continues to explore its potential applications,chestnut tannin remains a promising resource with diverse industrial uses.Highlighting new use,research and bioeconomy aspects,this study provides a unified perspective on chestnut tannin.New advanced applications will likely emerge shortly.展开更多
Biodiversity experiments have shown that soil organic carbon(SOC)is not only a function of plant diversity,but is also closely related to the nitrogen(N)-fixing plants.However,the effect of N-fixing trees on SOC chemi...Biodiversity experiments have shown that soil organic carbon(SOC)is not only a function of plant diversity,but is also closely related to the nitrogen(N)-fixing plants.However,the effect of N-fixing trees on SOC chemical stability is still little known,especially with the compounding effects of tree species diversity.An experimental field manipulation was established in subtropical plantations of southern China to explore the impacts of tree species richness(i.e.,one,two,four and six tree species)and with/without N-fixing trees on SOC chemical stability,as indicated by the ratio of easily oxidized organic carbon to SOC(EOC/SOC).Plant-derived C components in terms of hydrolysable plant lipids and lignin phenols were isolated from soils for evaluating their relative contributions to SOC chemical stability.The results showed that N-fixing tree species rather than tree species richness had a significant effect on EOC/SOC.Hydrolysable plant lipids and lignin phenols were negatively correlated with EOC/SOC,while hydrolysable plant lipids contributed more to EOC/SOC than lignin phenols,especially in the occurrence of N-fixing trees.The presence of N-fixing tree species led to an increase in soil N availability and a decrease in fungal abundance,promoting the selective retention of certain key components of hydrolysable plant lipids,thus enhancing SOC chemical stability.These findings underpin the crucial role of N-fixing trees in shaping SOC chemical stability,and therefore,preferential selection of N-fixing tree species in mixed plantations is an appropriate silvicultural strategy to improve SOC chemical stability in subtropical plantations.展开更多
Various forms of phosphorus (P) could become bioavailable such as from desorption, dissolution and enzymatic hydrolysis. Potential bioavailable P estimation is critical to minimize eutrophication in freshwater systems...Various forms of phosphorus (P) could become bioavailable such as from desorption, dissolution and enzymatic hydrolysis. Potential bioavailable P estimation is critical to minimize eutrophication in freshwater systems. Thus, this study was conducted to predict potential bioavailable P in the water columns and sediments and their relations with enzymatic hydrolysis, and estimate impacts of land use and anthropogenic activities on P bioavailability, P transport and water quality in the Bronx River, New York, USA. In sediment samples collected in 2006, total P (TP), total inor-ganic P (IP), total organic P (OP) and bioavailable P (BAP) were in highest concentrations in sites located at Bronx River Valley upstream in Westchester (site 2), Troublesome Brook (TB, site 4), Sprain Brook (SB, site 7b) and Bronx River estuary near Sound View Park (site 14) respectively. Also, phosphodiesterase and native phosphatases (PDEase and NPase) hydrolyzed distinguishingly high amounts of OP or enzymatically hydrolysable P (EHP) in samples from sites 4, 7b, 10 (New York Botanical Garden) and 14. Microbial P was in negative values (caused by different bacteria and microorganisms could not be paralyzed by chloroform), and the most negative concentrations were appeared at sties 4 and 14. Spatial comparisons among different locations showed distinguished characteristics in tributaries and estuary. In sediments collected in 2007, TP, BAP and IP were in highest concentrations at sites 7-SB, 11-Bronx Zoo, 12-East Tremont Ave Bridge where fresh and saline water meets, 13-estuary facing Hunts Point Waste Water Treatment Plant (HP WWTP) and 14-estuary along Sound View Park. Besides, PDEase-P highest concentrations ap-peared at sties 7, 13 and 11, NPase-P concentrations were highest at 7 and 11. Microbial P was highest at sties 11 and 14. Spatial variations showed that higher P content and more intense enzymatic hydrolysis in silty clay finer sediments at site 7, 11 and 13. Temporal variations between the two years’ data showed land use and 展开更多
Soil organic nitrogen(ON)accounts for more than 90%of the total nitrogen(TN)in paddy soils.Inadequate understanding of the different ON fractions in paddy soils and their corresponding bioavailability under different ...Soil organic nitrogen(ON)accounts for more than 90%of the total nitrogen(TN)in paddy soils.Inadequate understanding of the different ON fractions in paddy soils and their corresponding bioavailability under different climatic conditions has constrained the development of appropriate nutrient management strategies for rice production.In this study,we applied a modified Bremner method coupled with high-performance liquid chromatography to characterize how soil ON fractions and amino acid chirality varied under different climatic conditions at five typical rice production sites along a latitudinal gradient.According to the results,climate had no obvious influence on TN,nitrogen(N)form,and individual amino acid contents.However,the proportions of various N forms in TN had linear relationships with annual mean temperature(AMT),with high correlation coefficient(r)values.Amino acid components also exhibited similar trends,with r as high as 0.85.Most notably,consistent linear relationships were observed between the D/L ratios of several amino acids and AMT in paddy soils(r=0.18–0.92).Findings of this study provide insights into ON and amino acid dynamics in paddy soil systems under intensive production along climate gradients.展开更多
Terminalic acid 1, a new hydrolysable tannin, was isolated from the fruit of Terminalia chebula. Its structure was found to be 1-O-galloyl-2,4-chebuloyl-beta-D-glucopyranose by chemical method and H-1-NMR, C-13-NMR, H...Terminalic acid 1, a new hydrolysable tannin, was isolated from the fruit of Terminalia chebula. Its structure was found to be 1-O-galloyl-2,4-chebuloyl-beta-D-glucopyranose by chemical method and H-1-NMR, C-13-NMR, H-1-H-1 COSY, HMQC, HMBC and FAB-MS spectral analyses.展开更多
Non-isocyanate polyurethane(NIPU)foams from a commercial hydrolysable tannin extract,chestnut wood tannin extract,have been prepared to determine what chemical species and products are taking part in the reactions inv...Non-isocyanate polyurethane(NIPU)foams from a commercial hydrolysable tannin extract,chestnut wood tannin extract,have been prepared to determine what chemical species and products are taking part in the reactions involved.This method is based on two main steps:the reaction with dimethyl carbonate and the formation of urethane bonds by further reaction of the carbonated tannin with a diamine-like hexamethylene diamine.The hydroxyl groups on the tannin polyphenols and on the carbohydrates intimately linked with it and part of a hydrolysable tannin are the groups involved in these reactions.The carbohydrate skeleton of the hydrolysable tannin is also able to participate through its hydroxyl groups to the same two reactions rendering the whole molecular complex able to react to form NIPUs.The analysis by Matrix-Assisted Laser Desorption Ionization(MALDI-TOF)mass spectrometry and 13C Nuclear Magnetic Resonance(13C NMR)to further investigate the reaction mechanisms involved revealed the unsuspected complexity of chestnut hydrolysable tannin,with different fragments reacting in different manners forming a hardened network of considerable complexity.As the morphology and performance of these types of foams changes slightly with the change in the amount of glutaraldehyde and hexamine hardeners,the best performing foam formulation previously determined was scanned by SEM and analysed chemically for the structures formed.展开更多
Pomegranate peels are disposed of as waste even though it is an eminent source of total hydrolysable tannins(THT)and possesses a great worth for recycling.The present study was carried out with the hypothesis that pul...Pomegranate peels are disposed of as waste even though it is an eminent source of total hydrolysable tannins(THT)and possesses a great worth for recycling.The present study was carried out with the hypothesis that pulsed system ultrasound-assisted extraction(PSUAE)technique optimization would aid in retaining high extract yield and THT recovery yield from pomegranate peel extract(PPE)with enhanced antioxidant potential.The extraction was performed at various conditions regarding solvent concentration(30-90% of acetone),solvent-feed ratio(10-30 mL/g),extraction time(10-20 min),and ultrasound amplitude(40-80%)for maximum extract yield,THT and antioxidant activity(AA).To model and optimize the process conditions tools namely response surface methodology(RSM)and artificial neural network(ANN)were applied.For solvent concentration,solvent-feed ratio,extraction time,and amplitude the optimal conditions attained with aid of RSM and ANN were:56%,26.5 mL/g,15 min,55%,and 45%,23 mL/g,15 min,50% respectively.The extract yield and THT content determined with RSM and ANN optimized values were 51.2%,86.4 mg TAE/g,and 62%,98.1 mg TAE/g,respectively.The mean square error value displayed the minimum and R^(2) exhibited maximum value in case of ANN compared to RSM model.PSUAE significantly augmented the AA of PPE to 77.2±0.50% compared to 49.7±0.35% of conventional extraction.FTIR and HPLC analysis established that PPE produced from PSUAE contains a significant amount of THT compounds(gallic acid and tannic acid derivative).SEM elucidated that the sonication effect resulted in peel cell wall disruptions ensuing in elevated extraction of THT.Therefore,this pulsed mode of ultrasound extraction could be regarded as an easy,cost-effective,and competent technique for the extraction of preferred natural THT from pomegranate peels that possess high prospective to be applied in food and nutraceutical formulations.展开更多
ABSTRACT Non-isocyanate polyurethane(NIPU)foams using a hydrolysable tannin,also vulgarly called tannic acid,namely here commercial chestnut wood tannin extract was prepared.Compression strength did not appear to depe...ABSTRACT Non-isocyanate polyurethane(NIPU)foams using a hydrolysable tannin,also vulgarly called tannic acid,namely here commercial chestnut wood tannin extract was prepared.Compression strength did not appear to depend on the foam apparent density while the formulation composition of the NIPU foams has been shown to be more determinant.These NIPU foams appeared to be self-extinguishing once the high temperature flame is removed.The ignition time gave encouraging results but for improved fire resistance the foams may need some fire-retardant addition.FTIR spectrometry showed the formation of non-isocyanate urethane linkages.Thermogravimetric analysis indicated a good thermal resistance of these foams,with thermal degradation following four phases.First in the interval 25℃–120℃ range,mainly evaporation of water occurs with a maximal loss of 10%weight.In the 150℃–450℃ temperature range foams mass loss is of almost 70%.In particular in the 125℃–275℃ range occurs the degradation of some small molecular weight substances.In the 500℃–790℃ temperature range the foams do not present any further large degradation.展开更多
The leaves of Eucalyptus are abundant in natural resources as a novel potential antioxidant and have broad market prospect.Four of characteristic hydrolysable tannins from Eucalyptus leaves have been demonstrated grea...The leaves of Eucalyptus are abundant in natural resources as a novel potential antioxidant and have broad market prospect.Four of characteristic hydrolysable tannins from Eucalyptus leaves have been demonstrated great application potential as natural antioxidants in our previous research.In this study,the bioactive activities of another hydrolysable tannin isolated and identified as oenothein B(OEB)were evaluated.Content of bioactive compound(hydrolysable tannin)from different Eucalyptus species and regions in southern China were investigated.The results showed that OEB not only exerted anti-proliferative activity against HepG2 cell,but also showed higher cellular antioxidant activity than some common antioxidants.Generally,content of characteristic hydrolysable tannins decreased in the order of OEB>tellimagrandin I(T1)>pedunculagin>gemin D>pentagalloyl glucose(PGG).E.grandis×E.urophylla GL9 and E.urophylla×E.grandis could be recommended as new natural sources to exploit hydrolysable tannins because of high content,widely plantation and strong adaptability.This study supplied first insight on introduction of high cellular antioxidant activity of OEB and selecting the species and region to exploit natural antioxidants.It will promote the increasing of economic value of Eucalyptus.展开更多
This study aimed to identify and classify the type of plants used for tanning historical leathers using cost-effective Fourier transform infrared(FTIR)spectroscopy.The investigation was carried out on five plants(oak ...This study aimed to identify and classify the type of plants used for tanning historical leathers using cost-effective Fourier transform infrared(FTIR)spectroscopy.The investigation was carried out on five plants(oak bark,sumac,valonia,tara,and gallnut)and four historical leather samples from book bindings dating back to the Qajar period.Tannin extraction from both plants and leathers was performed using acetone-water solvent,and the samples were then subjected to FTIR spectroscopy.Pre-processing of the spectra included baseline correction,smoothing,and normalization.Principal component analysis(PCA)was used to identify the source of tannins based on FTIR results.FTIR was found to provide a good separation of condensed tannins from hydrolysable ones.However,PCA analysis allowed for the separation and identification of the type of plant used for tannin extraction.The examination of historical leather samples revealed that the primary classification based on the type of tannin is possible,but accurate identification faces challenges due to structural changes and degradation over time.展开更多
Li_(3)FeF_(6)has been the focus of research of fluorine-based cathode materials for lithium-ion batteries.Because of the low electronic conductivity of Li3 FeF6,the decrease of particle size,by an energyconsuming long...Li_(3)FeF_(6)has been the focus of research of fluorine-based cathode materials for lithium-ion batteries.Because of the low electronic conductivity of Li3 FeF6,the decrease of particle size,by an energyconsuming long-time ball milling process with carbon,is necessary to achieve a high electrochemical performance.The most successful method to enhance electrochemical activity,carbon coating,seemed to be impracticable,so far,for sensitive fluorides like Li3 FeF6.In this work,carbon coating on Li3 FeF6 particles has been successfully achieved for the first time,while avoiding both extended hydrolysis and Fe(Ⅲ)-Fe(Ⅱ)reduction.The heat treatment and atmosphere,yielding the maximal transformation of organic carbon to both graphitised and disordered carbon,has been determined.Carbon coating,with a thickness of approximately 2.5 nm,has been achieved by controlled thermal decomposition of glucose,under air,at 300℃.Raman and X-ray photoelectron spectroscopy(XPS)experiments have proved the existence of carbon and Fe2O3 on the surface of Li3FeF6 nanoparticles.XPS spectroscopy indicates the presence of organic residues from glucose decomposition.Attempts to further reduce the orga nic carbon content results in a decrease of the amorphous carbon coating layer.Optimised carbon-coated Li3 FeF6 nanoparticles deliver 122 mA h g^(-1)(85%of theoretical capacity)significantly higher than that of a noncoated sample(58 mA h g^(-1)).Even more,a significant beneficial effect of carbon coating on both capacity retention and coulombic efficiency is observed.展开更多
The use of flours or phenolic extracts obtained from non-traditional sources or agri-food industry by-products has been a strategy used to formulate new bakery products with characteristics of a functional food.Howeve...The use of flours or phenolic extracts obtained from non-traditional sources or agri-food industry by-products has been a strategy used to formulate new bakery products with characteristics of a functional food.However,phenolic compounds present great structural diversity,as well as the ability to interact in a complex way with the macromolecules that constitute the bread matrix.Therefore,the addition of these flours,extracts or pure compounds produces various effects on the microstructure of bread,and several of its sensory properties.This is mainly due to interactions between phenolic compounds and gluten proteins.The objective of this review is to analyze some of the most recent published works on the addition of phenolic compounds in wheat bread to identify the type of positive and negative effects that have been observed and how they can be related to the physicochemical interactions between phenolic compounds and the macromolecules that constitute the food matrix,mainly gluten.The effect of monomeric and polymeric phenolic compounds on the strength of these interactions and on the properties of dough and bread are discussed.展开更多
Tomentosin(1), a new C-glycosidic hydrolysable tannin, isolated from the leaves of Rhodomyrtus tomentosa. Its structure determined by chemical method and (1)HNMR spectroscopic analysis.
基于Si—O—C结构,合成了一种新型水敏感的Y型两亲性聚合物,研究了其在无水环境下的自组装行为。以水诱导组装体形成,研究了该物质的水敏感程度。结果表明,在0.6 m L/min的诱导速率及70%水含量下,合成的Y型两亲性聚合物自组装形成多层...基于Si—O—C结构,合成了一种新型水敏感的Y型两亲性聚合物,研究了其在无水环境下的自组装行为。以水诱导组装体形成,研究了该物质的水敏感程度。结果表明,在0.6 m L/min的诱导速率及70%水含量下,合成的Y型两亲性聚合物自组装形成多层囊泡结构,这种多层囊泡具有一定的水解稳定性,且具有温敏性和p H响应性。展开更多
In order to study the metabolomic responses of rapeseed meal on grass carp and the role that tannin plays in those responses,grass carp were fed four diets for an eight week trial.Two were practical diets:FM diet cont...In order to study the metabolomic responses of rapeseed meal on grass carp and the role that tannin plays in those responses,grass carp were fed four diets for an eight week trial.Two were practical diets:FM diet contained 10%fishmeal without rapeseed meal,RM diet contained 50%rapeseed meal without fishmeal;the other two were semi-purified diets without(T0)or with 1.25%(T1)of supplemental hydrolysable tannin.The tannin content in the RM diet was close to that of T1.The rate of weight gain for RM was significantly lower than FM,while the feed conversion ratio in the T1 was significantly higher than T0.The muscle lipid and protein content was significantly lower and glycogen higher in the RM and T1 compared to the other treatments.The percent of muscle-saturated fatty acid(SFA)in the RM and T1 groups was significantly lower than FM and T0 groups,respectively,while the mono-unsaturated fatty acid(MUFA)in the RM group was significantly higher than FM.The hepatic activities of alanine aminotransferase and aspartate aminotransferase were lower and the hepatic glycogen and malonaldehyde were higher in the T1 and RM than the other treatments.The total serum protein,globulin,and triglycerides were significantly higher in T1 and RM;the alanine aminotransferase in the T1 was significantly higher than T0;and the aspartate aminotransferase in the RM and T0 groups were significantly higher than the other treatments.In a metabolomic assay,29 differential metabolites were identified between T0 and T1,23 metabolites were downregulated,and 6 metabolites were upregulated in T1 compared to T0.Ninety-two differential metabolites were identified between FM and RM,31 metabolites were downregulated,and 61 metabolites were upregulated in RM compared to FM.These indicated that lipid utilization and carbohydrate metabolism might be improved,while the protein metabolism was suppressed by rapeseed meal.The abnormal protein and lipid metabolism may be partly caused by tannin in the rapeseed meal,as the tannin contained within the rapeseed mea展开更多
The soybean, cotton, maize and sorghum were planted in pot under low nitrogen, high nitrogen treatments, the soil available nitrogen constitution and con- version and utilization of nitrogen fertilizer were determined...The soybean, cotton, maize and sorghum were planted in pot under low nitrogen, high nitrogen treatments, the soil available nitrogen constitution and con- version and utilization of nitrogen fertilizer were determined, so as to provide techni- cal guidance for reasonable use and improving use efficiency of nitrogen fertilizer for different types of crops. Compared with the control with nitrogen but unplanted crop, growing soybean, cotton, maize, sorghum significantly decreased the soil available N contents by 53. 48%, 51.54%, 33.10%, 55.03%,and influenced the constitution of soil available N. Thereinto, growing soybean, cotton, maize and sorghum significantly decreased soil inorganic N contents by 85.41%, 83.09%, 70.89% and 83.35%,but increased soil hydrolysable organic N contents by 1.41, 1.53, 2.11 and 1.28 times, respectively; growing soybean, cotton, maize and sorghum significantly decreased the rate of soil inorganic N to available N by 68.61%, 65.09%, 56.47% and 63.00%, but increased the rate of soil hydrolysable organic N to available N by 4.18, 4.21, 3.66 and 4.08 times, respectively. Compared with the control, growing soybean, cotton, maize and sorghum significantly increased the transform rate of ammonium nitrogen fertilizer by 93.66%, 38.19%, 32.58% and 38.31% respectively, and growing soybean treatment had the highest increasing range; the nitrification rates of ammo- nium nitrogen fertilizer of growing soybean, cotton, maize and sorghum treatments were negative values, and growing soybean treatment had the highest decreasing amplitude. The ammonium nitrogen fertilizer use efficiency of growing soybean, cot- ton, maize and sorghum treatments were 52.01%, 28.31%, 24.16% and 28.40% re- spectively and growing soybean treatment had the highest value. In conclusion, growing crops suppressed the soil nitrification and accelerated the development of soil hydrolysable organic nitrogen by the utilization of soil available nitrogen and the alteration of soil environment, and hence impacted the constitution of s展开更多
基金This study is dedicated to the memory of Professor Farid Chemat(1969-2023)for all he has done to advance green extraction of natural products.Work of G.A.and G.L.P.is respectively supported by European Union NextGenerationEU-PNRR Sicilian Micro and Nano Technology Research and Innovation Center Innovation Ecosystem(SAMOTHRACE,Mission 4 Component 2-Investment 1.5 ECS00000022-CUPB63C22000620005)Made in Italy Circolare e Sostenibile(MICS,Mission 4 Component 2-Investment 1.3,PE00000004,CUPB53C22004060006).
文摘Chestnut tannin,extracted from the bark or wood of chestnut trees,possesses unique properties that make it valuable in various industries.It serves as a natural source of tannins,which are widely used in the production of leather,textiles,and wood preservation.As research continues to explore its potential applications,chestnut tannin remains a promising resource with diverse industrial uses.Highlighting new use,research and bioeconomy aspects,this study provides a unified perspective on chestnut tannin.New advanced applications will likely emerge shortly.
基金supported by the National Natural Science Foundation of China(31930078,32301559)the Ministry of Science and Technology of China(2021YFD2200405,2021YFD2200402)+1 种基金Fundamental Research Funds of CAF(CAFYBB2021ZW001)the program for scientific research start-up funds of Guangdong Ocean University。
文摘Biodiversity experiments have shown that soil organic carbon(SOC)is not only a function of plant diversity,but is also closely related to the nitrogen(N)-fixing plants.However,the effect of N-fixing trees on SOC chemical stability is still little known,especially with the compounding effects of tree species diversity.An experimental field manipulation was established in subtropical plantations of southern China to explore the impacts of tree species richness(i.e.,one,two,four and six tree species)and with/without N-fixing trees on SOC chemical stability,as indicated by the ratio of easily oxidized organic carbon to SOC(EOC/SOC).Plant-derived C components in terms of hydrolysable plant lipids and lignin phenols were isolated from soils for evaluating their relative contributions to SOC chemical stability.The results showed that N-fixing tree species rather than tree species richness had a significant effect on EOC/SOC.Hydrolysable plant lipids and lignin phenols were negatively correlated with EOC/SOC,while hydrolysable plant lipids contributed more to EOC/SOC than lignin phenols,especially in the occurrence of N-fixing trees.The presence of N-fixing tree species led to an increase in soil N availability and a decrease in fungal abundance,promoting the selective retention of certain key components of hydrolysable plant lipids,thus enhancing SOC chemical stability.These findings underpin the crucial role of N-fixing trees in shaping SOC chemical stability,and therefore,preferential selection of N-fixing tree species in mixed plantations is an appropriate silvicultural strategy to improve SOC chemical stability in subtropical plantations.
文摘Various forms of phosphorus (P) could become bioavailable such as from desorption, dissolution and enzymatic hydrolysis. Potential bioavailable P estimation is critical to minimize eutrophication in freshwater systems. Thus, this study was conducted to predict potential bioavailable P in the water columns and sediments and their relations with enzymatic hydrolysis, and estimate impacts of land use and anthropogenic activities on P bioavailability, P transport and water quality in the Bronx River, New York, USA. In sediment samples collected in 2006, total P (TP), total inor-ganic P (IP), total organic P (OP) and bioavailable P (BAP) were in highest concentrations in sites located at Bronx River Valley upstream in Westchester (site 2), Troublesome Brook (TB, site 4), Sprain Brook (SB, site 7b) and Bronx River estuary near Sound View Park (site 14) respectively. Also, phosphodiesterase and native phosphatases (PDEase and NPase) hydrolyzed distinguishingly high amounts of OP or enzymatically hydrolysable P (EHP) in samples from sites 4, 7b, 10 (New York Botanical Garden) and 14. Microbial P was in negative values (caused by different bacteria and microorganisms could not be paralyzed by chloroform), and the most negative concentrations were appeared at sties 4 and 14. Spatial comparisons among different locations showed distinguished characteristics in tributaries and estuary. In sediments collected in 2007, TP, BAP and IP were in highest concentrations at sites 7-SB, 11-Bronx Zoo, 12-East Tremont Ave Bridge where fresh and saline water meets, 13-estuary facing Hunts Point Waste Water Treatment Plant (HP WWTP) and 14-estuary along Sound View Park. Besides, PDEase-P highest concentrations ap-peared at sties 7, 13 and 11, NPase-P concentrations were highest at 7 and 11. Microbial P was highest at sties 11 and 14. Spatial variations showed that higher P content and more intense enzymatic hydrolysis in silty clay finer sediments at site 7, 11 and 13. Temporal variations between the two years’ data showed land use and
基金supported by the National Natural Science Foundation of China(No.41671296)Special Project on the Basis of National Science and Technology of China(No.2015FY110700).
文摘Soil organic nitrogen(ON)accounts for more than 90%of the total nitrogen(TN)in paddy soils.Inadequate understanding of the different ON fractions in paddy soils and their corresponding bioavailability under different climatic conditions has constrained the development of appropriate nutrient management strategies for rice production.In this study,we applied a modified Bremner method coupled with high-performance liquid chromatography to characterize how soil ON fractions and amino acid chirality varied under different climatic conditions at five typical rice production sites along a latitudinal gradient.According to the results,climate had no obvious influence on TN,nitrogen(N)form,and individual amino acid contents.However,the proportions of various N forms in TN had linear relationships with annual mean temperature(AMT),with high correlation coefficient(r)values.Amino acid components also exhibited similar trends,with r as high as 0.85.Most notably,consistent linear relationships were observed between the D/L ratios of several amino acids and AMT in paddy soils(r=0.18–0.92).Findings of this study provide insights into ON and amino acid dynamics in paddy soil systems under intensive production along climate gradients.
文摘Terminalic acid 1, a new hydrolysable tannin, was isolated from the fruit of Terminalia chebula. Its structure was found to be 1-O-galloyl-2,4-chebuloyl-beta-D-glucopyranose by chemical method and H-1-NMR, C-13-NMR, H-1-H-1 COSY, HMQC, HMBC and FAB-MS spectral analyses.
文摘Non-isocyanate polyurethane(NIPU)foams from a commercial hydrolysable tannin extract,chestnut wood tannin extract,have been prepared to determine what chemical species and products are taking part in the reactions involved.This method is based on two main steps:the reaction with dimethyl carbonate and the formation of urethane bonds by further reaction of the carbonated tannin with a diamine-like hexamethylene diamine.The hydroxyl groups on the tannin polyphenols and on the carbohydrates intimately linked with it and part of a hydrolysable tannin are the groups involved in these reactions.The carbohydrate skeleton of the hydrolysable tannin is also able to participate through its hydroxyl groups to the same two reactions rendering the whole molecular complex able to react to form NIPUs.The analysis by Matrix-Assisted Laser Desorption Ionization(MALDI-TOF)mass spectrometry and 13C Nuclear Magnetic Resonance(13C NMR)to further investigate the reaction mechanisms involved revealed the unsuspected complexity of chestnut hydrolysable tannin,with different fragments reacting in different manners forming a hardened network of considerable complexity.As the morphology and performance of these types of foams changes slightly with the change in the amount of glutaraldehyde and hexamine hardeners,the best performing foam formulation previously determined was scanned by SEM and analysed chemically for the structures formed.
文摘Pomegranate peels are disposed of as waste even though it is an eminent source of total hydrolysable tannins(THT)and possesses a great worth for recycling.The present study was carried out with the hypothesis that pulsed system ultrasound-assisted extraction(PSUAE)technique optimization would aid in retaining high extract yield and THT recovery yield from pomegranate peel extract(PPE)with enhanced antioxidant potential.The extraction was performed at various conditions regarding solvent concentration(30-90% of acetone),solvent-feed ratio(10-30 mL/g),extraction time(10-20 min),and ultrasound amplitude(40-80%)for maximum extract yield,THT and antioxidant activity(AA).To model and optimize the process conditions tools namely response surface methodology(RSM)and artificial neural network(ANN)were applied.For solvent concentration,solvent-feed ratio,extraction time,and amplitude the optimal conditions attained with aid of RSM and ANN were:56%,26.5 mL/g,15 min,55%,and 45%,23 mL/g,15 min,50% respectively.The extract yield and THT content determined with RSM and ANN optimized values were 51.2%,86.4 mg TAE/g,and 62%,98.1 mg TAE/g,respectively.The mean square error value displayed the minimum and R^(2) exhibited maximum value in case of ANN compared to RSM model.PSUAE significantly augmented the AA of PPE to 77.2±0.50% compared to 49.7±0.35% of conventional extraction.FTIR and HPLC analysis established that PPE produced from PSUAE contains a significant amount of THT compounds(gallic acid and tannic acid derivative).SEM elucidated that the sonication effect resulted in peel cell wall disruptions ensuing in elevated extraction of THT.Therefore,this pulsed mode of ultrasound extraction could be regarded as an easy,cost-effective,and competent technique for the extraction of preferred natural THT from pomegranate peels that possess high prospective to be applied in food and nutraceutical formulations.
文摘ABSTRACT Non-isocyanate polyurethane(NIPU)foams using a hydrolysable tannin,also vulgarly called tannic acid,namely here commercial chestnut wood tannin extract was prepared.Compression strength did not appear to depend on the foam apparent density while the formulation composition of the NIPU foams has been shown to be more determinant.These NIPU foams appeared to be self-extinguishing once the high temperature flame is removed.The ignition time gave encouraging results but for improved fire resistance the foams may need some fire-retardant addition.FTIR spectrometry showed the formation of non-isocyanate urethane linkages.Thermogravimetric analysis indicated a good thermal resistance of these foams,with thermal degradation following four phases.First in the interval 25℃–120℃ range,mainly evaporation of water occurs with a maximal loss of 10%weight.In the 150℃–450℃ temperature range foams mass loss is of almost 70%.In particular in the 125℃–275℃ range occurs the degradation of some small molecular weight substances.In the 500℃–790℃ temperature range the foams do not present any further large degradation.
基金supported by the General project of the Natural Science Foundation of Guangdong Province,China(2022A1515010907)the National Key R&D Program(2016YFD0600806)National Natural Science Foundation of China(31700501).
文摘The leaves of Eucalyptus are abundant in natural resources as a novel potential antioxidant and have broad market prospect.Four of characteristic hydrolysable tannins from Eucalyptus leaves have been demonstrated great application potential as natural antioxidants in our previous research.In this study,the bioactive activities of another hydrolysable tannin isolated and identified as oenothein B(OEB)were evaluated.Content of bioactive compound(hydrolysable tannin)from different Eucalyptus species and regions in southern China were investigated.The results showed that OEB not only exerted anti-proliferative activity against HepG2 cell,but also showed higher cellular antioxidant activity than some common antioxidants.Generally,content of characteristic hydrolysable tannins decreased in the order of OEB>tellimagrandin I(T1)>pedunculagin>gemin D>pentagalloyl glucose(PGG).E.grandis×E.urophylla GL9 and E.urophylla×E.grandis could be recommended as new natural sources to exploit hydrolysable tannins because of high content,widely plantation and strong adaptability.This study supplied first insight on introduction of high cellular antioxidant activity of OEB and selecting the species and region to exploit natural antioxidants.It will promote the increasing of economic value of Eucalyptus.
文摘This study aimed to identify and classify the type of plants used for tanning historical leathers using cost-effective Fourier transform infrared(FTIR)spectroscopy.The investigation was carried out on five plants(oak bark,sumac,valonia,tara,and gallnut)and four historical leather samples from book bindings dating back to the Qajar period.Tannin extraction from both plants and leathers was performed using acetone-water solvent,and the samples were then subjected to FTIR spectroscopy.Pre-processing of the spectra included baseline correction,smoothing,and normalization.Principal component analysis(PCA)was used to identify the source of tannins based on FTIR results.FTIR was found to provide a good separation of condensed tannins from hydrolysable ones.However,PCA analysis allowed for the separation and identification of the type of plant used for tannin extraction.The examination of historical leather samples revealed that the primary classification based on the type of tannin is possible,but accurate identification faces challenges due to structural changes and degradation over time.
基金This work was financially supported by the“Agencia Estatal de Investigación/Fondo Europeo de Desarrollo Regional”(FEDER/UE)and“Comunidad de Madrid”(Nos.MAT2016-78632-C4-1-R and S2013/MIT-2753)Characterisation techniques for this research were partially financed by the EU funds(Nos.POPW.01.03.00-20.034/09-00 and POPW.01.03.00-20-004/11-00)。
文摘Li_(3)FeF_(6)has been the focus of research of fluorine-based cathode materials for lithium-ion batteries.Because of the low electronic conductivity of Li3 FeF6,the decrease of particle size,by an energyconsuming long-time ball milling process with carbon,is necessary to achieve a high electrochemical performance.The most successful method to enhance electrochemical activity,carbon coating,seemed to be impracticable,so far,for sensitive fluorides like Li3 FeF6.In this work,carbon coating on Li3 FeF6 particles has been successfully achieved for the first time,while avoiding both extended hydrolysis and Fe(Ⅲ)-Fe(Ⅱ)reduction.The heat treatment and atmosphere,yielding the maximal transformation of organic carbon to both graphitised and disordered carbon,has been determined.Carbon coating,with a thickness of approximately 2.5 nm,has been achieved by controlled thermal decomposition of glucose,under air,at 300℃.Raman and X-ray photoelectron spectroscopy(XPS)experiments have proved the existence of carbon and Fe2O3 on the surface of Li3FeF6 nanoparticles.XPS spectroscopy indicates the presence of organic residues from glucose decomposition.Attempts to further reduce the orga nic carbon content results in a decrease of the amorphous carbon coating layer.Optimised carbon-coated Li3 FeF6 nanoparticles deliver 122 mA h g^(-1)(85%of theoretical capacity)significantly higher than that of a noncoated sample(58 mA h g^(-1)).Even more,a significant beneficial effect of carbon coating on both capacity retention and coulombic efficiency is observed.
基金This review was written as part of the project“Specific and non-specific interactions between proteins and proanthocyanidins”funded by Mexico´s National Council of Science and Technology(CONACYT,SEP CB 2016-286449).
文摘The use of flours or phenolic extracts obtained from non-traditional sources or agri-food industry by-products has been a strategy used to formulate new bakery products with characteristics of a functional food.However,phenolic compounds present great structural diversity,as well as the ability to interact in a complex way with the macromolecules that constitute the bread matrix.Therefore,the addition of these flours,extracts or pure compounds produces various effects on the microstructure of bread,and several of its sensory properties.This is mainly due to interactions between phenolic compounds and gluten proteins.The objective of this review is to analyze some of the most recent published works on the addition of phenolic compounds in wheat bread to identify the type of positive and negative effects that have been observed and how they can be related to the physicochemical interactions between phenolic compounds and the macromolecules that constitute the food matrix,mainly gluten.The effect of monomeric and polymeric phenolic compounds on the strength of these interactions and on the properties of dough and bread are discussed.
文摘Tomentosin(1), a new C-glycosidic hydrolysable tannin, isolated from the leaves of Rhodomyrtus tomentosa. Its structure determined by chemical method and (1)HNMR spectroscopic analysis.
文摘基于Si—O—C结构,合成了一种新型水敏感的Y型两亲性聚合物,研究了其在无水环境下的自组装行为。以水诱导组装体形成,研究了该物质的水敏感程度。结果表明,在0.6 m L/min的诱导速率及70%水含量下,合成的Y型两亲性聚合物自组装形成多层囊泡结构,这种多层囊泡具有一定的水解稳定性,且具有温敏性和p H响应性。
基金the Key Laboratory of Freshwater Aquatic Genetic Resources,the Ministry of Agriculture,the Shanghai Ocean University,Shanghai,China.
文摘In order to study the metabolomic responses of rapeseed meal on grass carp and the role that tannin plays in those responses,grass carp were fed four diets for an eight week trial.Two were practical diets:FM diet contained 10%fishmeal without rapeseed meal,RM diet contained 50%rapeseed meal without fishmeal;the other two were semi-purified diets without(T0)or with 1.25%(T1)of supplemental hydrolysable tannin.The tannin content in the RM diet was close to that of T1.The rate of weight gain for RM was significantly lower than FM,while the feed conversion ratio in the T1 was significantly higher than T0.The muscle lipid and protein content was significantly lower and glycogen higher in the RM and T1 compared to the other treatments.The percent of muscle-saturated fatty acid(SFA)in the RM and T1 groups was significantly lower than FM and T0 groups,respectively,while the mono-unsaturated fatty acid(MUFA)in the RM group was significantly higher than FM.The hepatic activities of alanine aminotransferase and aspartate aminotransferase were lower and the hepatic glycogen and malonaldehyde were higher in the T1 and RM than the other treatments.The total serum protein,globulin,and triglycerides were significantly higher in T1 and RM;the alanine aminotransferase in the T1 was significantly higher than T0;and the aspartate aminotransferase in the RM and T0 groups were significantly higher than the other treatments.In a metabolomic assay,29 differential metabolites were identified between T0 and T1,23 metabolites were downregulated,and 6 metabolites were upregulated in T1 compared to T0.Ninety-two differential metabolites were identified between FM and RM,31 metabolites were downregulated,and 61 metabolites were upregulated in RM compared to FM.These indicated that lipid utilization and carbohydrate metabolism might be improved,while the protein metabolism was suppressed by rapeseed meal.The abnormal protein and lipid metabolism may be partly caused by tannin in the rapeseed meal,as the tannin contained within the rapeseed mea
基金Supported by National Natural Science Foundation of China(41371259)Hubei Natural Science Foundation(2014CFB545)~~
文摘The soybean, cotton, maize and sorghum were planted in pot under low nitrogen, high nitrogen treatments, the soil available nitrogen constitution and con- version and utilization of nitrogen fertilizer were determined, so as to provide techni- cal guidance for reasonable use and improving use efficiency of nitrogen fertilizer for different types of crops. Compared with the control with nitrogen but unplanted crop, growing soybean, cotton, maize, sorghum significantly decreased the soil available N contents by 53. 48%, 51.54%, 33.10%, 55.03%,and influenced the constitution of soil available N. Thereinto, growing soybean, cotton, maize and sorghum significantly decreased soil inorganic N contents by 85.41%, 83.09%, 70.89% and 83.35%,but increased soil hydrolysable organic N contents by 1.41, 1.53, 2.11 and 1.28 times, respectively; growing soybean, cotton, maize and sorghum significantly decreased the rate of soil inorganic N to available N by 68.61%, 65.09%, 56.47% and 63.00%, but increased the rate of soil hydrolysable organic N to available N by 4.18, 4.21, 3.66 and 4.08 times, respectively. Compared with the control, growing soybean, cotton, maize and sorghum significantly increased the transform rate of ammonium nitrogen fertilizer by 93.66%, 38.19%, 32.58% and 38.31% respectively, and growing soybean treatment had the highest increasing range; the nitrification rates of ammo- nium nitrogen fertilizer of growing soybean, cotton, maize and sorghum treatments were negative values, and growing soybean treatment had the highest decreasing amplitude. The ammonium nitrogen fertilizer use efficiency of growing soybean, cot- ton, maize and sorghum treatments were 52.01%, 28.31%, 24.16% and 28.40% re- spectively and growing soybean treatment had the highest value. In conclusion, growing crops suppressed the soil nitrification and accelerated the development of soil hydrolysable organic nitrogen by the utilization of soil available nitrogen and the alteration of soil environment, and hence impacted the constitution of s