Free cholesterol has been considered to be a critical risk factor of nonalcoholic fatty liver disease(NAFLD).It remains unknown whether dietary intake of condensed tannins(CTs)have distinguishable effects to alleviate...Free cholesterol has been considered to be a critical risk factor of nonalcoholic fatty liver disease(NAFLD).It remains unknown whether dietary intake of condensed tannins(CTs)have distinguishable effects to alleviate liver damage caused by a high cholesterol diet.Male C57BL/6 mice were fed a high cholesterol diet for 6 weeks,and given CTs treatment at a dosage of 200 mg/(kg·day)at the same time.The results indicated that compared with mice fed a normal diet,a high cholesterol diet group resulted in significant weight loss,dysregulation of lipid metabolism in blood and liver,and oxidative stress in the liver,but CTs treatment dramatically reversed these negative effects.Hematoxylin and eosin(H&E)staining and frozen section observation manifested that CTs treatment could effectively reduce the deposition of liver cholesterol and tissue necrosis caused by high cholesterol intake.CTs alleviated liver injury mainly by regulating the expression of related genes in cholesterol metabolism pathway and AMPK phosphorylation.Our results confirmed that CTs have remarkable cholesterol lowering and anti-liver injury effects in vivo.展开更多
Condensed and hydrolysable tannins are non-toxic natural polyphenols that are a commercial commodity industrialized for tanning hides to obtain leather and for a growing number of other industrial applications mainly ...Condensed and hydrolysable tannins are non-toxic natural polyphenols that are a commercial commodity industrialized for tanning hides to obtain leather and for a growing number of other industrial applications mainly to substitute petroleum-based products.They are a definite class of sustainable materials of the forestry industry.They have been in operation for hundreds of years to manufacture leather and now for a growing number of applications in a variety of other industries,such as wood adhesives,metal coating,pharmaceutical/medical applications and several others.This review presents the main sources,either already or potentially commercial of this forestry by-materials,their industrial and laboratory extraction systems,their systems of analysis with their advantages and drawbacks,be these methods so simple to even appear primitive but nonetheless of proven effectiveness,or very modern and instrumental.It constitutes a basic but essential summary of what is necessary to know of these sustainable materials.In doing so,the review highlights some of the main challenges that remain to be addressed to deliver the quality and economics of tannin supply necessary to fulfill the industrial production requirements for some materials-based uses.展开更多
The ruin of several civil engineering works occurs due to shear rupture of the ground. When the stress is greater than the shear resistance, the internal friction angle and the cohesion of the soil loosen and rupture ...The ruin of several civil engineering works occurs due to shear rupture of the ground. When the stress is greater than the shear resistance, the internal friction angle and the cohesion of the soil loosen and rupture occurs. Cement and lime are often used to stabilize soils and improve soil strength. The costs and environmental problems of these technologies raise concerns and challenge researchers to innovate with clean, inexpensive materials, accessible to the most disadvantaged social classes. The question that this study seeks to answer is whether the binders derived from plant tannins, which also stabilize soils, improve the shear resistance of these soils. To do this, we determined for silty sand the shear parameters, notably the cohesion and the angle of internal friction in the non-stabilized state and when they are stabilized with the powder of the bark of the Bridelia under different water states. The results show that the addition of Bridelia powder to silty sand increases the cohesion of the soil by nearly 70.71% and the friction angle by 4.31%. But in unfavourable water conditions, the cohesion and internal friction angle of the silty sand material improved with Bridelia bark powder drops drastically by nearly 81.56%. but does not dissolve completely as for the same material. When it is not stabilized. This information is an invaluable contribution in the search for solutions to increase the durability of earthen constructions by improving the water-repellent properties of soils.展开更多
The objective of this work is to develop new biosourced insulating composites from rice husks and wood chips that can be used in the building sector. It appears from the properties of the precursors that rice chips an...The objective of this work is to develop new biosourced insulating composites from rice husks and wood chips that can be used in the building sector. It appears from the properties of the precursors that rice chips and husks are materials which can have good thermal conductivity and therefore the combination of these precursors could make it possible to obtain panels with good insulating properties. With regard to environmental and climatic constraints, the composite panels formulated at various rates were tested and the physico-mechanical and thermal properties showed that it was essential to add a crosslinker in order to increase certain solicitation. an incorporation rate of 12% to 30% made it possible to obtain panels with low thermal conductivity, a low surface water absorption capacity and which gives the composite good thermal insulation and will find many applications in the construction and real estate sector. Finally, new solutions to improve the fire reaction of the insulation panels are tested which allows to identify suitable solutions for the developed composites. In view of the flame tests, the panels obtained are good and can effectively combat fire safety in public buildings.展开更多
Extracts of plant origin,particularly tannins,are attracting growing interest for the sustainable development of materials in the industrial sector.The discovery of new tannins is therefore necessary.The aim of this w...Extracts of plant origin,particularly tannins,are attracting growing interest for the sustainable development of materials in the industrial sector.The discovery of new tannins is therefore necessary.The aim of this work was to contribute to the understanding of the properties of Paraberlinia bifoliolata tannin by Matrix Assisted Laser Desorption Ionization Time of Flight Mass Spectroscopy MALDI-TOF/MS and Carbon 13 Nuclear Magnetic Resonance(13C NMR).The chemical composition of tannin extracted from Paraberlinia bifoliolata bark was determined,as was the mechanical strength of the resin hardened with Acacia nilotica extracts.Yield by successive water extraction was 35%.MALDI-TOF/MS analysis revealed the presence of three new compounds in this tannin,previously unknown in this family of extracts.These are 3-hydroxyproline acid,N-methyl-4-hydroxypipecolic acid and N-methyl-5-dihydroxypipecolic acid.The identification of the above molecules means that this tannin can be used for industrial applications,as a resin in the manufacture of particleboard and in the formulation of green corrosion inhibitors.This information is reinforced by 13C NMR spectrometry,which indicates the presence of several polyflavonoid units,confirming the condensed nature of the tannin.Thermomechanical analysis of the resin formed by the purified tannin of Paraberlinia bifoliolata to which a vegetal biohardener has been added provided a Modulus of Elasticity(MOE)value of 4840 MPa at 150℃,confirming its possible use as a binder resin in the manufacture of wood panels as well as for the formulation of a corrosion inhibitor.展开更多
This paper summarized of the chemistry characteristics of tannins and their various adverse effects onmammalian herbivore, including the chemical nature of hydrolyzable and condensed tannins, their analysis mathods, a...This paper summarized of the chemistry characteristics of tannins and their various adverse effects onmammalian herbivore, including the chemical nature of hydrolyzable and condensed tannins, their analysis mathods, and the tannins antifeedant mechanisms.展开更多
Objective:To investigate the changes in total phenols,flavonoids,tannins,vitamin E, β-carotene and antioxidant activity during soaking of three white sorghum varieties.Methods: The changes in total phenols,total ilav...Objective:To investigate the changes in total phenols,flavonoids,tannins,vitamin E, β-carotene and antioxidant activity during soaking of three white sorghum varieties.Methods: The changes in total phenols,total ilavonoids,tannins,phenolic acids compounds,flavonoid components,vitamin E,P-carotene and antioxidant activity during soaking of sorghum grains were determined.Results:Total phenols,total flavonoids,tannins,vitamin E,P-carotene and antioxidant activity in raw sorghum were ranged from 109.21 to 116.70,45.91 to 54.69,1.39 to 21.79 mg/100 g,1.74 to 5.25,0.54 to 1.19 mg/kg and 21.72%to 27.69%and 25.29%to 31.97%,respectively. The above measured compounds were significantly decreased after soaking.p-Hydroxybenzoic acid,vanillic acid,syringic acid and cinnamic acid represent the major phenolic acids in Dorado variety.While ferulic acid,p-coumaric acid,gallic acid and caffeic acid represent the major phenolic acids in Shandaweel-6.On the other hand,protocatechuic acid represents the major phenolic acids in Giza-15.Regarding flavonoids components,Dorado was the highest variety in kampferol and naringenin while Shandaweel-6 was the highest variety in luteolin, apigenin,hypersoid,quercelin and christen.Finally,Giza-15 was the highest variety in catechin. Phenolic acids,flavonoid compounds and antioxidant activities were decreased after soaking. Conclusions:Sorghum varieties have moderate quantities from total phenols,total flavonoids, tannins,phenolic acids compounds,flavonoid components,vitamin E,P-carotene and antioxidant activity which decreased after soaking.展开更多
Objective:To evaluate the protective effect of tannins from Ficus racemosa(F.racemosa) on the lipid profile and antioxidant parameters in high fat meal and streptozotocin induced hypercholestremia associated diabetes ...Objective:To evaluate the protective effect of tannins from Ficus racemosa(F.racemosa) on the lipid profile and antioxidant parameters in high fat meal and streptozotocin induced hypercholestremia associated diabetes model in rats.Methods:The crude tannin fraction was separated from the acetone(70%v/v) bark extract of F.racemosa.Oral administratipn of tannin fraction(TF)(100 & 200 mg/kg body weight) to rats fed with high fat meal for 30 days (4%cholesterol,1%cholic acid,0.5%egg albumin) and injected with streptozotocin(35 mg/ kg i.p.in citrate buffer on 14th day).Results:The administration of TF significantly reverse the increased blood glucose,total cholesterol,triglycerides,low density lipoprotein and also significandy restored the insulin and high density lipoprotein in the serum.In addition tannins significantly restored the activity of antioxidant enzymes such as superoxide dismutase,catalase and decreased the,glutathione peroxidase,and glutathione,thereby restoring the antioxidant status of the organs to almost normal levels.Conclutions:The results of this study show that two different doses of tannin supplementation had a favorable effect on plasma glucose and lipid profile concentrations.It also had an influence on attenuating oxidative stress in diabetic tats.展开更多
Background: Pine bark is a rich source of phytochemical compounds including tannins, phenolic acids, anthocyanins, and fatty acids. These phytochemicals have potential to significantly impact on animal health and ani...Background: Pine bark is a rich source of phytochemical compounds including tannins, phenolic acids, anthocyanins, and fatty acids. These phytochemicals have potential to significantly impact on animal health and animal production. The goal of this work is to measure the effects of tannins in ground pine bark as a partial feed replacement on feed intake, dietary apparent digestibility, nitrogen balance, and mineral retention in meat goats. Results: Eighteen Kiko cross goats (initial BW = 31.8 ± 1.49 kg) were randomly assigned to three treatment groups (n = 6). Dietary treatments were tested: control (0 % pine bark powder (PB) and 30 % wheat straw (WS)); ] 5 % PB and 15 % WS, and 30 % PB and 0 % WS. Although dry matter (DM) intake and digestibility were not affected (P〉 0.10) by feeding PB, neutral detergent fiber (linear; P= 0.01), acid detergent fiber (linear; P= 0.001) and lignin digestibility (linear; P= 0.01) decreased, and crude protein (CP) digestibility tended to decrease (P=0.09) as PB increased in the diet, apparent retention of Ca (P= 0.09), P (P=0.03), Mg (P= 0.01), Mn (P= 0.01), Zn (P= 0.01) and Fe (P= 0.09) also increased linearly. Nitrogen intake and fecal N excretion were not affected (P〉 0.05) by addition of PB in the diet, but N balance in the body was quadratically increased (P〈 0.01) in the 15 % PB diet compared to other diets. This may be due to more rumen escape protein and less excreted N in the urine with the 15 % PB diet. The study showed that a moderate level of tannin-containing pine bark supplementation could improve gastrointestinal nitrogen balance with the aim of improving animal performance. Conclusion: These results suggest that tannin-containing PB has negative impact on fiber, lignin, and protein digestibility, but positively impacted on N-balance.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
Studies on the corrosion behaviour of mild steel electrodes in inhibited hydrochloric acid are described. Conventional weight loss measurements show that a maximum concentration of 140 ppm of tannin from Rhizophora ra...Studies on the corrosion behaviour of mild steel electrodes in inhibited hydrochloric acid are described. Conventional weight loss measurements show that a maximum concentration of 140 ppm of tannin from Rhizophora racemosa is required to achieve 72% corrosion inhibition. Similar concentration of tannin: H3PO4 in ratio 1:1 gave 61% inhibition efficiency, whereas efficiency obtained for phosphoric acid as inhibitor in the same environment was 55%. Corrosion rates obtained over six hours of exposure in 1M HCl solution at inhibitor concentrations of 140 ppm are 2 mA/cm2, 2.4 mA/cm2, 2.6 mA/cm2 and 6 mA/cm2 for tannin, tannin/H3PO4 and H3PO4-inhibited and uninhibited specimens respectively. Natural atmospheric exposure studies revealed that specimens treated in H3PO4 resisted corrosion for three weeks, while tannin treated specimens suffered corrosion attack after one week of exposure tests.展开更多
Proanthocyanidins are formed in the chlorophyllous organs of Tracheophyta from a redifferentiation of chloroplasts involving the thylakoidal membrane and lumen. With the purpose to help researchers of concerned discip...Proanthocyanidins are formed in the chlorophyllous organs of Tracheophyta from a redifferentiation of chloroplasts involving the thylakoidal membrane and lumen. With the purpose to help researchers of concerned disciplines to identify such chloroplasts, we described herein the morphologies of functional and redifferentiating chloroplasts in various members of Tracheophyta. The most obvious sign of redifferentiation is a tremendous swelling of the chloroplast which turns obese. De novo genesis of osmiophilic materials is also characteristic, either as single dots attached to the inner face of the swollen thylakoidal membrane which will yield the tannosomes, or as pearl necklace-shaped structures protruding into the lumen;this last formation can be viewed as a giant tannosome forming finally stromal chlorotannic accretions. Whatever their mode of formation is, tannosomes are expulsed from the chloroplast as shuttles.展开更多
[Objectives]The effects of condensed quebracho tannins on the production performance and blood routine indices of Simmental fattening cattle were investigated experimentally.[Methods]Twenty four Simmental fattening ca...[Objectives]The effects of condensed quebracho tannins on the production performance and blood routine indices of Simmental fattening cattle were investigated experimentally.[Methods]Twenty four Simmental fattening cattle were selected and randomly divided into two treatment groups according to their body weight,with 12 animals in each group.The diet of the control group consisted of beef cattle concentrate supplement+silage+hay,and the diet of the experimental group consisted of beef cattle concentrate supplement+silage+hay+tannins,and the experimental period was 30 d.[Results]Compared with the control group,the addition of tannins[30 g/(cattle·d)]to the diet of beef cattle increased the daily weight gain of Simmental beef cattle by 24.68%(P<0.01),while the feed conversion ratio decreased by 2.57%(P>0.05).The gross profit per cattle increased by 973.63 yuan,and the economic benefit increased by 114.78%.Platelets were higher in the experimental group than in the control group(P<0.01);hemoglobin was lower in the experimental group than in the control group(P<0.01);leukocytes,neutrophils,monocytes and lymphocytes were lower in the experimental group than in the control group(P<0.01);and erythrocytes were lower in the experimental group than in the control group(P<0.05).[Conclusions]This study provides a theoretical basis for the rational utilization of quebracho tannins.展开更多
In order to make Mucuna seeds consumable, seeds are treated according to the following procedures: boiling, soaking followed by boiling in the presence of 0.5% KOH and finally soaking for a long time followed by boili...In order to make Mucuna seeds consumable, seeds are treated according to the following procedures: boiling, soaking followed by boiling in the presence of 0.5% KOH and finally soaking for a long time followed by boiling in the presence of 0.5% KOH, so that tannins can be removed. Preliminary studies done on the raw seeds of four Mucuna species revealed the presence of tannins. The results showed that the crushed seeds contained all high tannin with the content of 0.370 g GAE/100g DM, 0.336 g GAE/100g DM;0.266 g GAE/100g DM and 0.203 g GAE/100g DM for Mucuna deerigiana, Mucuna nagaland, Mucuna cochinchinensis and Mucuna rajada respectively. The different methods of seed treatment significantly reduced the tannin content in Mucuna seeds. The method of soaking the seeds for 12 hours and then scalding in the presence of 0.5% KOH reduced tannins in Mucuna deerigiana, Mucuna nagaland, Mucuna cochinchinensis, and Mucuna rajada seeds by 47.29%;48.21%;66.16%;and 15.76% respectively. This method gave the highest tannin reduction rate.展开更多
In the current research study, an attempt is made to modification of polyvinyl chloride (PVC) by grafting with biologically based phenolic resin, namely, tannins. The reaction was carried out at 110°C in DMF ...In the current research study, an attempt is made to modification of polyvinyl chloride (PVC) by grafting with biologically based phenolic resin, namely, tannins. The reaction was carried out at 110°C in DMF solution. FTIR spectra show the presence of phenolic hydroxylic groups and other functional groups of tannins into the PVC-tannins derivative. Evaluation of the new PVC derivative as polymeric antioxidant for high density polyethylene (HDPE) was the main purpose of this study. Samples of HDPE containing (0.0, 0.5 and 2.0) %W/W from PVC-tannins and pure HDPE were exposed to thermal program by differential scanning calorimetry (DSC) by temperature sweep from 100°C to 350°C. DSC scans of the thermal oxidation process of pure HDPE as well as HDPE with PVC derivative show oxidation exothermic stage started at 195°C and continues to 285°C. The samples of polyethylene contain the PVC-tannins show more resistance to oxidation reactions until 215°C for HDPE sample stabilized with 0.5% and 221°C for HDPE stabilized with 2.0%. Faster initiation of degradation rate was observed when HDPE contained PVC-tannins. According to the DSC analysis, the PVC derivative can participate in stabilization mechanism of HDPE but at limited performance.展开更多
Due to the complexity of structure,it is difficult to determine the content of sorghum tannins.The current method for the determination of sorghum tannins is the Ferric ammonium citrate assay described in ISO 9648.How...Due to the complexity of structure,it is difficult to determine the content of sorghum tannins.The current method for the determination of sorghum tannins is the Ferric ammonium citrate assay described in ISO 9648.However,the standard tannic acid(TA)used in the ISO 9648 method is significantly different in both structure and dynamics from sorghum tannins,resulting in inaccurate quantitative result.Furthermore,the extraction solvent,75%dimethylformamide(DMF),used in each step of this method had large toxicity to human.Hence,the objective of this study is to optimize the ISO 9648 method by selecting proper standard and extraction solvents so as to enhance the accuracy and safety.In this study,Sephadex LH-20 chromatography combined with high pressure liquid chromatography was used to purify and identify the extracted sorghum tannin(ST).Then,commercial TA,epicatechin(EA),grape seed procyanidin(PA)were selected as the standard and ST was used as reference for Ferric ammonium citrate assay to compare the effects of the three standards.Furthermore,the extraction rates of sorghum tannins in the presence of several low toxic solvents,such as absolute ethanol,absolute methanol,70%ethanol solution,70%methanol solution and 70%acetone solution,were compared to determine the alternative solvents of 75%DMF solution.The results showed that PA was superior to TA and EA in structure,with satisfactory color yield close to ST,and higher accuracy than TA.In terms of the extraction solvent,70%acetone solution was selected to replace 75%DMF solution because of its higher extraction yield(only next to 75%DMF)and low toxicity.Verification experiment results showed that both the recovery rate and the repeatability of the optimized method met the requirements of AOCO.Moreover,the optimized method,with higher accuracy and safety than the ISO 9648 method,can be applied widely in laboratory.展开更多
This study was conducted to investigate effects of supplementing two doses of quebracho tannins (QT;100 or 200 g/cow/d;QT<sub>100</sub> or QT<sub>200</sub>) pre and post parturition to thirty H...This study was conducted to investigate effects of supplementing two doses of quebracho tannins (QT;100 or 200 g/cow/d;QT<sub>100</sub> or QT<sub>200</sub>) pre and post parturition to thirty Holstein dairy cows on Dry Matter Intake (DMI), milk yield and composition, blood metabolites and reproductive performance for 12 weeks. There were no significant changes in DMI due to QT at transition period of dairy cows. QT supplementation at either level decreased (P 0.05) the total number of ovarian follicles, number of large follicles, diameter of largest follicle, number of small follicles, number and diameter of corpus luteum, and progesterone concentration. The inclusion of QT increased days open and number of services per conception, which consequently decreased conception rate, compared to the control cows. QT100 decreased (P展开更多
Restrictions on heavy metals,especially chromium,have encouraged alternative tanning systems that can reduce environmental and human health risks from conventional chrome-based tanning.In this work,metal-free combinat...Restrictions on heavy metals,especially chromium,have encouraged alternative tanning systems that can reduce environmental and human health risks from conventional chrome-based tanning.In this work,metal-free combination tanning was developed by using vegetable tannins and a triazine-based syntan containing active chlorine groups(SACC).Specifically,the relationship between leather performance(e.g.,hydrothermal stability and organoleptic properties)and technical protocols(e.g.,types and dose of tannins)was systematically established.The optimized protocol involving a unique procedure(i.e.,10%SACC pre-tanning,shaving,and 25%wattle tanning)endowed the leather with high shrinkage temperature(~92℃)and met the Chinese standards for shoe upper leather(QB/T 1873-2010).Our method not only produces zero chrome-containing solid wastes,but also uses~75%less tannin for leather manufacture.The excellent leather performance was ascribed to the synergistic effects,where SACC and wattle diffused into collagen fibrils and may bind to collagen via covalent,hydrogen and ionic bonding,locking the hierarchical structure of collagen from microfibrils to fiber bundles.Moreover,we summarized these findings and proposed a diffusion-binding-locking mechanism,providing new insights for current tanning theory.Together with the biodegradable spent tanning liquor,this approach will underpin the development of sustainable leather manufacture.展开更多
Naturally occurring plant compounds including tannins, saponins and essential oils are extensively assessed as natural alternatives to in-feed antibiotics.Tannins are a group of polyphenolic compounds that are widely ...Naturally occurring plant compounds including tannins, saponins and essential oils are extensively assessed as natural alternatives to in-feed antibiotics.Tannins are a group of polyphenolic compounds that are widely present in plant region and possess various biological activities including antimicrobial,anti-parasitic, anti-viral, antioxidant, anti-inflammatory, immunomodulation, etc.Therefore, tannins are the major research subject in developing natural alternative to in-feed antibiotics.Strong protein affinity is the well-recognized property of plant tannins, which has successfully been applied to ruminant nutrition to decrease protein degradation in the rumen, and thereby improve protein utilization and animal production efficiency.Incorporations of tannin-containing forage in ruminant diets to control animal pasture bloat, intestinal parasite and pathogenic bacteria load are another 3 important applications of tannins in ruminant animals.Tannins have traditionally been regarded as "anti-nutritional factor" for monogastric animals and poultry, but recent researches have revealed some of them, when applied in appropriate manner, improved intestinal microbial ecosystem, enhanced gut health and hence increased productive performance.The applicability of plant tannins as an alternative to in-feed antibiotics depends on many factors that contribute to the great variability in their observed efficacies.展开更多
基金supported by the National Basic Research Program of China(2013CB127106)。
文摘Free cholesterol has been considered to be a critical risk factor of nonalcoholic fatty liver disease(NAFLD).It remains unknown whether dietary intake of condensed tannins(CTs)have distinguishable effects to alleviate liver damage caused by a high cholesterol diet.Male C57BL/6 mice were fed a high cholesterol diet for 6 weeks,and given CTs treatment at a dosage of 200 mg/(kg·day)at the same time.The results indicated that compared with mice fed a normal diet,a high cholesterol diet group resulted in significant weight loss,dysregulation of lipid metabolism in blood and liver,and oxidative stress in the liver,but CTs treatment dramatically reversed these negative effects.Hematoxylin and eosin(H&E)staining and frozen section observation manifested that CTs treatment could effectively reduce the deposition of liver cholesterol and tissue necrosis caused by high cholesterol intake.CTs alleviated liver injury mainly by regulating the expression of related genes in cholesterol metabolism pathway and AMPK phosphorylation.Our results confirmed that CTs have remarkable cholesterol lowering and anti-liver injury effects in vivo.
文摘Condensed and hydrolysable tannins are non-toxic natural polyphenols that are a commercial commodity industrialized for tanning hides to obtain leather and for a growing number of other industrial applications mainly to substitute petroleum-based products.They are a definite class of sustainable materials of the forestry industry.They have been in operation for hundreds of years to manufacture leather and now for a growing number of applications in a variety of other industries,such as wood adhesives,metal coating,pharmaceutical/medical applications and several others.This review presents the main sources,either already or potentially commercial of this forestry by-materials,their industrial and laboratory extraction systems,their systems of analysis with their advantages and drawbacks,be these methods so simple to even appear primitive but nonetheless of proven effectiveness,or very modern and instrumental.It constitutes a basic but essential summary of what is necessary to know of these sustainable materials.In doing so,the review highlights some of the main challenges that remain to be addressed to deliver the quality and economics of tannin supply necessary to fulfill the industrial production requirements for some materials-based uses.
文摘The ruin of several civil engineering works occurs due to shear rupture of the ground. When the stress is greater than the shear resistance, the internal friction angle and the cohesion of the soil loosen and rupture occurs. Cement and lime are often used to stabilize soils and improve soil strength. The costs and environmental problems of these technologies raise concerns and challenge researchers to innovate with clean, inexpensive materials, accessible to the most disadvantaged social classes. The question that this study seeks to answer is whether the binders derived from plant tannins, which also stabilize soils, improve the shear resistance of these soils. To do this, we determined for silty sand the shear parameters, notably the cohesion and the angle of internal friction in the non-stabilized state and when they are stabilized with the powder of the bark of the Bridelia under different water states. The results show that the addition of Bridelia powder to silty sand increases the cohesion of the soil by nearly 70.71% and the friction angle by 4.31%. But in unfavourable water conditions, the cohesion and internal friction angle of the silty sand material improved with Bridelia bark powder drops drastically by nearly 81.56%. but does not dissolve completely as for the same material. When it is not stabilized. This information is an invaluable contribution in the search for solutions to increase the durability of earthen constructions by improving the water-repellent properties of soils.
文摘The objective of this work is to develop new biosourced insulating composites from rice husks and wood chips that can be used in the building sector. It appears from the properties of the precursors that rice chips and husks are materials which can have good thermal conductivity and therefore the combination of these precursors could make it possible to obtain panels with good insulating properties. With regard to environmental and climatic constraints, the composite panels formulated at various rates were tested and the physico-mechanical and thermal properties showed that it was essential to add a crosslinker in order to increase certain solicitation. an incorporation rate of 12% to 30% made it possible to obtain panels with low thermal conductivity, a low surface water absorption capacity and which gives the composite good thermal insulation and will find many applications in the construction and real estate sector. Finally, new solutions to improve the fire reaction of the insulation panels are tested which allows to identify suitable solutions for the developed composites. In view of the flame tests, the panels obtained are good and can effectively combat fire safety in public buildings.
基金supported by the Institut de la Francophonie pour le Developpement Durable(IFDD/Canada)/Projet de Deploiement des Technologies et Innovations Environnementales(PDTIE)funded by Organisation Internationale de la Francophonie(OIF)the Organisation of African,Caribbean and Pacific States and the European Union(EU)(FED/220/421-370)the Local Materials Promotion Authority(MIPROMALO)of the Ministry of Scientific Research and Innovation of Cameroon who made it possible for this scientific work to be carried out.
文摘Extracts of plant origin,particularly tannins,are attracting growing interest for the sustainable development of materials in the industrial sector.The discovery of new tannins is therefore necessary.The aim of this work was to contribute to the understanding of the properties of Paraberlinia bifoliolata tannin by Matrix Assisted Laser Desorption Ionization Time of Flight Mass Spectroscopy MALDI-TOF/MS and Carbon 13 Nuclear Magnetic Resonance(13C NMR).The chemical composition of tannin extracted from Paraberlinia bifoliolata bark was determined,as was the mechanical strength of the resin hardened with Acacia nilotica extracts.Yield by successive water extraction was 35%.MALDI-TOF/MS analysis revealed the presence of three new compounds in this tannin,previously unknown in this family of extracts.These are 3-hydroxyproline acid,N-methyl-4-hydroxypipecolic acid and N-methyl-5-dihydroxypipecolic acid.The identification of the above molecules means that this tannin can be used for industrial applications,as a resin in the manufacture of particleboard and in the formulation of green corrosion inhibitors.This information is reinforced by 13C NMR spectrometry,which indicates the presence of several polyflavonoid units,confirming the condensed nature of the tannin.Thermomechanical analysis of the resin formed by the purified tannin of Paraberlinia bifoliolata to which a vegetal biohardener has been added provided a Modulus of Elasticity(MOE)value of 4840 MPa at 150℃,confirming its possible use as a binder resin in the manufacture of wood panels as well as for the formulation of a corrosion inhibitor.
文摘This paper summarized of the chemistry characteristics of tannins and their various adverse effects onmammalian herbivore, including the chemical nature of hydrolyzable and condensed tannins, their analysis mathods, and the tannins antifeedant mechanisms.
基金financially supported by Department of Biochemistry,Faculty of Agriculture.Cario University,and Food Technology Research Institute(FTRI)
文摘Objective:To investigate the changes in total phenols,flavonoids,tannins,vitamin E, β-carotene and antioxidant activity during soaking of three white sorghum varieties.Methods: The changes in total phenols,total ilavonoids,tannins,phenolic acids compounds,flavonoid components,vitamin E,P-carotene and antioxidant activity during soaking of sorghum grains were determined.Results:Total phenols,total flavonoids,tannins,vitamin E,P-carotene and antioxidant activity in raw sorghum were ranged from 109.21 to 116.70,45.91 to 54.69,1.39 to 21.79 mg/100 g,1.74 to 5.25,0.54 to 1.19 mg/kg and 21.72%to 27.69%and 25.29%to 31.97%,respectively. The above measured compounds were significantly decreased after soaking.p-Hydroxybenzoic acid,vanillic acid,syringic acid and cinnamic acid represent the major phenolic acids in Dorado variety.While ferulic acid,p-coumaric acid,gallic acid and caffeic acid represent the major phenolic acids in Shandaweel-6.On the other hand,protocatechuic acid represents the major phenolic acids in Giza-15.Regarding flavonoids components,Dorado was the highest variety in kampferol and naringenin while Shandaweel-6 was the highest variety in luteolin, apigenin,hypersoid,quercelin and christen.Finally,Giza-15 was the highest variety in catechin. Phenolic acids,flavonoid compounds and antioxidant activities were decreased after soaking. Conclusions:Sorghum varieties have moderate quantities from total phenols,total flavonoids, tannins,phenolic acids compounds,flavonoid components,vitamin E,P-carotene and antioxidant activity which decreased after soaking.
文摘Objective:To evaluate the protective effect of tannins from Ficus racemosa(F.racemosa) on the lipid profile and antioxidant parameters in high fat meal and streptozotocin induced hypercholestremia associated diabetes model in rats.Methods:The crude tannin fraction was separated from the acetone(70%v/v) bark extract of F.racemosa.Oral administratipn of tannin fraction(TF)(100 & 200 mg/kg body weight) to rats fed with high fat meal for 30 days (4%cholesterol,1%cholic acid,0.5%egg albumin) and injected with streptozotocin(35 mg/ kg i.p.in citrate buffer on 14th day).Results:The administration of TF significantly reverse the increased blood glucose,total cholesterol,triglycerides,low density lipoprotein and also significandy restored the insulin and high density lipoprotein in the serum.In addition tannins significantly restored the activity of antioxidant enzymes such as superoxide dismutase,catalase and decreased the,glutathione peroxidase,and glutathione,thereby restoring the antioxidant status of the organs to almost normal levels.Conclutions:The results of this study show that two different doses of tannin supplementation had a favorable effect on plasma glucose and lipid profile concentrations.It also had an influence on attenuating oxidative stress in diabetic tats.
基金support from the European Union through a Marie Curie Initial Training Network(PITN-GA-2011-289377,LegumePlus)
文摘Background: Pine bark is a rich source of phytochemical compounds including tannins, phenolic acids, anthocyanins, and fatty acids. These phytochemicals have potential to significantly impact on animal health and animal production. The goal of this work is to measure the effects of tannins in ground pine bark as a partial feed replacement on feed intake, dietary apparent digestibility, nitrogen balance, and mineral retention in meat goats. Results: Eighteen Kiko cross goats (initial BW = 31.8 ± 1.49 kg) were randomly assigned to three treatment groups (n = 6). Dietary treatments were tested: control (0 % pine bark powder (PB) and 30 % wheat straw (WS)); ] 5 % PB and 15 % WS, and 30 % PB and 0 % WS. Although dry matter (DM) intake and digestibility were not affected (P〉 0.10) by feeding PB, neutral detergent fiber (linear; P= 0.01), acid detergent fiber (linear; P= 0.001) and lignin digestibility (linear; P= 0.01) decreased, and crude protein (CP) digestibility tended to decrease (P=0.09) as PB increased in the diet, apparent retention of Ca (P= 0.09), P (P=0.03), Mg (P= 0.01), Mn (P= 0.01), Zn (P= 0.01) and Fe (P= 0.09) also increased linearly. Nitrogen intake and fecal N excretion were not affected (P〉 0.05) by addition of PB in the diet, but N balance in the body was quadratically increased (P〈 0.01) in the 15 % PB diet compared to other diets. This may be due to more rumen escape protein and less excreted N in the urine with the 15 % PB diet. The study showed that a moderate level of tannin-containing pine bark supplementation could improve gastrointestinal nitrogen balance with the aim of improving animal performance. Conclusion: These results suggest that tannin-containing PB has negative impact on fiber, lignin, and protein digestibility, but positively impacted on N-balance.
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.
文摘Studies on the corrosion behaviour of mild steel electrodes in inhibited hydrochloric acid are described. Conventional weight loss measurements show that a maximum concentration of 140 ppm of tannin from Rhizophora racemosa is required to achieve 72% corrosion inhibition. Similar concentration of tannin: H3PO4 in ratio 1:1 gave 61% inhibition efficiency, whereas efficiency obtained for phosphoric acid as inhibitor in the same environment was 55%. Corrosion rates obtained over six hours of exposure in 1M HCl solution at inhibitor concentrations of 140 ppm are 2 mA/cm2, 2.4 mA/cm2, 2.6 mA/cm2 and 6 mA/cm2 for tannin, tannin/H3PO4 and H3PO4-inhibited and uninhibited specimens respectively. Natural atmospheric exposure studies revealed that specimens treated in H3PO4 resisted corrosion for three weeks, while tannin treated specimens suffered corrosion attack after one week of exposure tests.
文摘Proanthocyanidins are formed in the chlorophyllous organs of Tracheophyta from a redifferentiation of chloroplasts involving the thylakoidal membrane and lumen. With the purpose to help researchers of concerned disciplines to identify such chloroplasts, we described herein the morphologies of functional and redifferentiating chloroplasts in various members of Tracheophyta. The most obvious sign of redifferentiation is a tremendous swelling of the chloroplast which turns obese. De novo genesis of osmiophilic materials is also characteristic, either as single dots attached to the inner face of the swollen thylakoidal membrane which will yield the tannosomes, or as pearl necklace-shaped structures protruding into the lumen;this last formation can be viewed as a giant tannosome forming finally stromal chlorotannic accretions. Whatever their mode of formation is, tannosomes are expulsed from the chloroplast as shuttles.
基金Supported by National Modern Agriculture(Beef Cattle and Yak)Industrial Technology System(CARS-37)Feed Industry Expert Technical Service Team Project of Ningxia Agriculture and Rural Affairs DepartmentAnimal Husbandry New Technology Promotion Project of Ningxia Feed Workstation.
文摘[Objectives]The effects of condensed quebracho tannins on the production performance and blood routine indices of Simmental fattening cattle were investigated experimentally.[Methods]Twenty four Simmental fattening cattle were selected and randomly divided into two treatment groups according to their body weight,with 12 animals in each group.The diet of the control group consisted of beef cattle concentrate supplement+silage+hay,and the diet of the experimental group consisted of beef cattle concentrate supplement+silage+hay+tannins,and the experimental period was 30 d.[Results]Compared with the control group,the addition of tannins[30 g/(cattle·d)]to the diet of beef cattle increased the daily weight gain of Simmental beef cattle by 24.68%(P<0.01),while the feed conversion ratio decreased by 2.57%(P>0.05).The gross profit per cattle increased by 973.63 yuan,and the economic benefit increased by 114.78%.Platelets were higher in the experimental group than in the control group(P<0.01);hemoglobin was lower in the experimental group than in the control group(P<0.01);leukocytes,neutrophils,monocytes and lymphocytes were lower in the experimental group than in the control group(P<0.01);and erythrocytes were lower in the experimental group than in the control group(P<0.05).[Conclusions]This study provides a theoretical basis for the rational utilization of quebracho tannins.
文摘In order to make Mucuna seeds consumable, seeds are treated according to the following procedures: boiling, soaking followed by boiling in the presence of 0.5% KOH and finally soaking for a long time followed by boiling in the presence of 0.5% KOH, so that tannins can be removed. Preliminary studies done on the raw seeds of four Mucuna species revealed the presence of tannins. The results showed that the crushed seeds contained all high tannin with the content of 0.370 g GAE/100g DM, 0.336 g GAE/100g DM;0.266 g GAE/100g DM and 0.203 g GAE/100g DM for Mucuna deerigiana, Mucuna nagaland, Mucuna cochinchinensis and Mucuna rajada respectively. The different methods of seed treatment significantly reduced the tannin content in Mucuna seeds. The method of soaking the seeds for 12 hours and then scalding in the presence of 0.5% KOH reduced tannins in Mucuna deerigiana, Mucuna nagaland, Mucuna cochinchinensis, and Mucuna rajada seeds by 47.29%;48.21%;66.16%;and 15.76% respectively. This method gave the highest tannin reduction rate.
文摘In the current research study, an attempt is made to modification of polyvinyl chloride (PVC) by grafting with biologically based phenolic resin, namely, tannins. The reaction was carried out at 110°C in DMF solution. FTIR spectra show the presence of phenolic hydroxylic groups and other functional groups of tannins into the PVC-tannins derivative. Evaluation of the new PVC derivative as polymeric antioxidant for high density polyethylene (HDPE) was the main purpose of this study. Samples of HDPE containing (0.0, 0.5 and 2.0) %W/W from PVC-tannins and pure HDPE were exposed to thermal program by differential scanning calorimetry (DSC) by temperature sweep from 100°C to 350°C. DSC scans of the thermal oxidation process of pure HDPE as well as HDPE with PVC derivative show oxidation exothermic stage started at 195°C and continues to 285°C. The samples of polyethylene contain the PVC-tannins show more resistance to oxidation reactions until 215°C for HDPE sample stabilized with 0.5% and 221°C for HDPE stabilized with 2.0%. Faster initiation of degradation rate was observed when HDPE contained PVC-tannins. According to the DSC analysis, the PVC derivative can participate in stabilization mechanism of HDPE but at limited performance.
基金funding of the ISO/TC34/SC4the Construction of Wheat Technology System in Henan Province(S201701-G06)special fund。
文摘Due to the complexity of structure,it is difficult to determine the content of sorghum tannins.The current method for the determination of sorghum tannins is the Ferric ammonium citrate assay described in ISO 9648.However,the standard tannic acid(TA)used in the ISO 9648 method is significantly different in both structure and dynamics from sorghum tannins,resulting in inaccurate quantitative result.Furthermore,the extraction solvent,75%dimethylformamide(DMF),used in each step of this method had large toxicity to human.Hence,the objective of this study is to optimize the ISO 9648 method by selecting proper standard and extraction solvents so as to enhance the accuracy and safety.In this study,Sephadex LH-20 chromatography combined with high pressure liquid chromatography was used to purify and identify the extracted sorghum tannin(ST).Then,commercial TA,epicatechin(EA),grape seed procyanidin(PA)were selected as the standard and ST was used as reference for Ferric ammonium citrate assay to compare the effects of the three standards.Furthermore,the extraction rates of sorghum tannins in the presence of several low toxic solvents,such as absolute ethanol,absolute methanol,70%ethanol solution,70%methanol solution and 70%acetone solution,were compared to determine the alternative solvents of 75%DMF solution.The results showed that PA was superior to TA and EA in structure,with satisfactory color yield close to ST,and higher accuracy than TA.In terms of the extraction solvent,70%acetone solution was selected to replace 75%DMF solution because of its higher extraction yield(only next to 75%DMF)and low toxicity.Verification experiment results showed that both the recovery rate and the repeatability of the optimized method met the requirements of AOCO.Moreover,the optimized method,with higher accuracy and safety than the ISO 9648 method,can be applied widely in laboratory.
文摘This study was conducted to investigate effects of supplementing two doses of quebracho tannins (QT;100 or 200 g/cow/d;QT<sub>100</sub> or QT<sub>200</sub>) pre and post parturition to thirty Holstein dairy cows on Dry Matter Intake (DMI), milk yield and composition, blood metabolites and reproductive performance for 12 weeks. There were no significant changes in DMI due to QT at transition period of dairy cows. QT supplementation at either level decreased (P 0.05) the total number of ovarian follicles, number of large follicles, diameter of largest follicle, number of small follicles, number and diameter of corpus luteum, and progesterone concentration. The inclusion of QT increased days open and number of services per conception, which consequently decreased conception rate, compared to the control cows. QT100 decreased (P
基金National Natural Science Foundation of China(21978177,22178230)is gratefully acknowledged.
文摘Restrictions on heavy metals,especially chromium,have encouraged alternative tanning systems that can reduce environmental and human health risks from conventional chrome-based tanning.In this work,metal-free combination tanning was developed by using vegetable tannins and a triazine-based syntan containing active chlorine groups(SACC).Specifically,the relationship between leather performance(e.g.,hydrothermal stability and organoleptic properties)and technical protocols(e.g.,types and dose of tannins)was systematically established.The optimized protocol involving a unique procedure(i.e.,10%SACC pre-tanning,shaving,and 25%wattle tanning)endowed the leather with high shrinkage temperature(~92℃)and met the Chinese standards for shoe upper leather(QB/T 1873-2010).Our method not only produces zero chrome-containing solid wastes,but also uses~75%less tannin for leather manufacture.The excellent leather performance was ascribed to the synergistic effects,where SACC and wattle diffused into collagen fibrils and may bind to collagen via covalent,hydrogen and ionic bonding,locking the hierarchical structure of collagen from microfibrils to fiber bundles.Moreover,we summarized these findings and proposed a diffusion-binding-locking mechanism,providing new insights for current tanning theory.Together with the biodegradable spent tanning liquor,this approach will underpin the development of sustainable leather manufacture.
基金partially funded by Alberta Agriculture and Forestry,Agriculture and Agri-Food Canadaprojects of China Postdoctoral Science Foundation (Grant No.:2017M611930)+1 种基金Natural Science Foundation of Jiangsu Province of China (No.:BK20170494)China Agriculture Research System (CARS-36)
文摘Naturally occurring plant compounds including tannins, saponins and essential oils are extensively assessed as natural alternatives to in-feed antibiotics.Tannins are a group of polyphenolic compounds that are widely present in plant region and possess various biological activities including antimicrobial,anti-parasitic, anti-viral, antioxidant, anti-inflammatory, immunomodulation, etc.Therefore, tannins are the major research subject in developing natural alternative to in-feed antibiotics.Strong protein affinity is the well-recognized property of plant tannins, which has successfully been applied to ruminant nutrition to decrease protein degradation in the rumen, and thereby improve protein utilization and animal production efficiency.Incorporations of tannin-containing forage in ruminant diets to control animal pasture bloat, intestinal parasite and pathogenic bacteria load are another 3 important applications of tannins in ruminant animals.Tannins have traditionally been regarded as "anti-nutritional factor" for monogastric animals and poultry, but recent researches have revealed some of them, when applied in appropriate manner, improved intestinal microbial ecosystem, enhanced gut health and hence increased productive performance.The applicability of plant tannins as an alternative to in-feed antibiotics depends on many factors that contribute to the great variability in their observed efficacies.