Quebracho Tannin Research Articles

Isocyanate free condensed tannin-based polyurethanes

Condensed flavonoid tannins from Maritime Pine (Pinus pinaster), Mimosa (Acacia mearnsii), and Radiata Pine barks, and Quebracho (Schinopsis lorentzii and balansae) wood, were first reacted with dimethyl carbonate. Then hexamethylenediamine was added to these mixtures to form urethane linkages. The resulting materials were analyzed by Fourier transform infrared (FTIR) spectroscopy, matrix assisted laser desorption ionization time of flight (MALDI-TOF) mass spectrometry, gel permeation chromatography (GPC), and thermogravimetric analysis (TGA). Finally the resulting analysis indicated that the products obtained are polyurethanes. Initial wood coating applications tests were carried out under conditions of higher temperature and some pressure, and the contact angle of the surface coatings so prepared was measured.

Green synthesis of silver nanoparticles using tannins

Abstract Colloidal silver nanoparticles were prepared by rapid green synthesis using different tannin sources as reducing agent viz. chestnut (CN), mangrove (MG) and quebracho (QB). The aqueous silver ions when exposed to CN, MG and QB tannins were reduced which resulted in formation of silver nanoparticles. The resultant silver nanoparticles were characterized using UV-Visible, X-ray diffraction (XRD), scanning electron microscopy (SEM/EDX), and transmission electron microscopy (TEM) techniques. Furthermore, the possible mechanism of nanoparticles synthesis was also derived using FT-IR analysis. Spectroscopy analysis revealed that the synthesized nanoparticles were within 30 to 75 nm in size, while XRD results showed that nanoparticles formed were crystalline with face centered cubic geometry.

Tannins: the organic depressants alternative in selective flotation of sulfides

The use of quebracho extract as a pyrite depressing agent to improve Cu/Fe ratio in copper minerals flotation was studied. The depressing effect in the case of pure pyrite, pure chalcopyrite and a sample of disseminated copper ore was tested considering different pH values and modifiers, and different levels of tannin addition. Results show that quebracho extract can be considered a cleaner option in these processes.

Effects of a selection of additives on in vitro ruminal methanogenesis and in situ and in vivo NDF digestibility.

The effects of 18 essential oils, yeast, Quebracho tannin and Quillaja saponin on ruminal methane and gas production (GP) were studied in vitro. A lactating cow diet was incubated with rumen inoculum. Doses of the additives (mg/L) were: essential oils = 500; tannin = 67; yeast = 8.35 and 16.7; and saponin = 300. Lemongrass, estragole, eugenol, geraniol, limonen, thyme oil and thymol produced less gas (overall mean 33.8 mL/200 mg dry matter (DM)) than control (43.6 mL/200 mg DM; P < 0.001). Methane produced (mL/200 mg DM) by guaiacol (10.7), lemongrass (9.6), limonene (11.4), thyme oil (10.9) and thymol (2.1) was lower than control (12.5) (P < 0.001). Methane percentage on total GP was lower (P < 0.001) for cinnamic alcohol (25.4), guaiacol (24.5), thymol (19.7) and vanillin (26.3) than control (28.8). In a second experiment, thymol, guaiacol and yeast were added to the diet of dry fistulated cows to determine in situ neutral detergent fiber digestibility (NDFD) of six forages and in vivo dietary NDFD. Thymol and yeast decreased in situ NDFD after 24 h (33.9% and 33.5% vs. 38.1%; P = 0.008). Thymol decreased in vivo total tract NDFD (40.8% vs. 51.4%; P = 0.02). Differences in GP and methane levels were registered within classes of additives. A careful selection of additives may allow for the manipulation of ruminal fermentation.

Structure and properties of rigid foams derived from quebracho tannin

The first highly porous organic rigid foams based on condensed tannin extracted from quebracho tree (Schinopsis sp.) are reported. Samples having different densities have been prepared and characterised. Their porous structure and physical properties have been compared with those of foams prepared in similar conditions but based on mimosa or pine tannins. We show that the properties of quebracho foams are comparable, and in some cases better, than those made from other tannins. Quebracho and mimosa present very similar behaviours, attributed to the fact that the corresponding flavonoid units have identical reactive A-rings. In contrast, pine foams behave differently, due to their different A-ring. The results indicate that quebracho is thus an excellent alternative to mimosa for producing thermally insulating tannin foams presenting good mechanical performances.

Effect of tannin on increasing UF adhesive performance at high temperature investigated by TMA and TGA analysis

Tannins have been largely studied as wood additives and wood adhesives. In a perspective of a desirably increased utilization of natural raw material in the wood timber industries, this study provides further and specific information on the use of condensed tannins to improve the heat resistance of urea–formaldehyde (UF) resins. The results obtained by thermomechanical and thermogravimetric analyses show that high percentage (33 and 50 %) of quebracho tannin in UF-tannin blend dramatically improves the overall UF thermal resistance, but 50 % of tannin decreases the maximum value of modulus of elasticity (MOE) of the bonded joint. The best balance between mechanical performance and decreased degradation at high temperature is obtained with 33 % of quebracho tannin. The MOE value of UF + 33 % of quebracho tannin at 260 °C is seven times greater than MOE of UF control. Thermograms show that quebracho tannin has a beneficial effect on increasing the resistance of glue-mix to degradation induced by temperature. When the content of tannin in the glue-mix is increased up to 50 %, the resin degrades completely at about 670 °C, i.e. more than 50 °C higher than neat UF resin. This improvement is related mainly to the resorcinol-type ring structure of tannin and the alkaline pH of UF + quebracho tannin glue mix that confer a higher resistance against joint degradation to UF even at elevated temperatures.

Perspectives in the use of tannins as alternative to antimicrobial growth promoter factors in poultry.

Antibiotics have been included in the formulation of feed for livestock production for more than 40 years as a strategy to improve feed conversion rates and to reduce costs. The use of antimicrobials as growth-promoting factors (AGP) in sub-therapeutic doses for long periods is particularly favorable for the selection of antimicrobial resistant microorganisms. In the last years, global concern about development of antimicrobial resistance and transference of resistance genes from animal to human strains has been rising. Removal of AGP from animal diets involves tremendous pressure on the livestock and poultry farmers, one of the main consequences being a substantial increase in the incidence of infectious diseases with the associated increase in the use of antibiotics for therapy, and concomitantly, economic cost. Therefore, alternatives to AGP are urgently needed. The challenge is to implement new alternatives without affecting the production performances of livestock and avoiding the increase of antimicrobial resistant microorganisms. Plant extracts and purified derived substances are showing promising results for animal nutrition, either from their efficacy as well as from an economical point of view. Tannins are plant derived compounds that are being successfully used as additives in poultry feed to control diseases and to improve animal performance. Successful use of any of these extracts as feed additives must ensure a product of consistent quality in enough quantity to fulfill the actual requirements of the poultry industry. Chestnut (hydrolysable) and Quebracho (condensed) tannins are probably the most readily available commercial products that are covering those needs. The present report intends to analyze the available data supporting their use.

CONCENTRATION OF CHROMITE BY MEANS OF MAGNETIC CARRIER USING SODIUM OLEATE AND OTHER REAGENTS

Chromite recovery was studied using a magnetic carrier technology. Heavy media grade magnetite was used as the magnetic carrier. The effect of various reagents such as sodium oleate (NaOl) as a collector and carboxymethyl cellulose (CMC) as well as quebracho tannin as depressants on chromite removal was investigated. The effects of pH and reagent dosages were also determined. First, the zeta potential measurements were performed for different minerals in the absence and presence of NaOl, and then magnetic carrier tests were carried out under conditions based on zeta potential measurements. The magnetic carrier tests performed in the case of individual minerals (i.e. single minerals) showed that chromite (recovery of 95.1%) could be separated from serpentine (recovery of 3.2%) whereas it could not be separated from olivine. The best chromite concentrates containing 42.1% Cr2O3 were obtained with a 76% recovery from a synthetic mixtures of chromite and serpentine under optimum test conditions, that is at pH 10.5, 5.10 -5 M NaOl, 20 g/Mg CMC, 0.5 g magnetite and 500 g/Mg kerosene (the feed contained 27% Cr2O3). Slime tailings of Turkish Maadin Company, Kavak Chrome Concentrating Plant in Eskisehir, which contain fine chromite, serpentine and olivine, were also investigated. It was found that chromite could not be satisfactorily recovered from the original slime sample in the presence and absence of NaOl by using the magnetic carrier technology. Additional FTIR studies performed with the investigated minerals showed that NaOl adsorption on chromite was greater than that on serpentine and magnetite minerals. It was also found that NaOl adsorption on serpentine is significantly reduced in the presence of magnetite while it increases only slightly on chromite.

Effect of Quebracho Tannin Extract on Soybean and Linseed Oil Biohydrogenation by Solid Associated Bacteria: An in vitro Study

An in vitro trial was carried out to study the effects of Quebracho tannins extract (QE) on fatty acid profile of rumen solid adherent bacteria (SAB) during the fermentation of diets supplemented with soybean or linseed oil, as sources of linoleic (LA; 18:2 n-6) and α-linolenic acid (α-LNA; 18:3 n-3), respectively. Two control diets were prepared using a basal mixture of grass hay [760 g/kg on dry matter (DM)], soybean meal (55 g/kg DM), barley meal (130 g/kg DM), vitamin mineral premix (20 g/kg DM) and 35 g/kg DM of soybean (SOC diet) or linseed oil (LOC diet) as lipid supplement. Other two diets (SOCT and LOCT) were obtained by integrating SOC and LOC with QE (49 g/kg DM). The results confirmed that Quebracho tannins may be an effective method for reducing in SAB the biohydrogenation of LA (17.3 vs 34.5 g/100 g of fatty acid in SOC and SOCT, respectively) and LNA (10.7 vs 21.4 g/100 g of fatty acid in LOC and LOCT, respectively), but not for increasing the rumen accumulation of cis9, trans11 18:2 (0.77 vs 0.32 g/100 g of fatty acid in SOC and SOCT, respec tively; 0.51 vs 0.43 g/100 g of fatty acid in LOC and LOCT, respectively) and trans11 18:1 (6.15 vs 3.64 g/100 g of fatty acid in SOC and SOCT, respectively; 5.53 vs 4.47 g/100 g of fatty acid in LOC and LOCT, respectively).

New lab-made coagulant based on Schinopsis balansae tannin extract: synthesis optimization and preliminary tests on refractory water pollutants

Quebracho colorado tannin extract was used as a coagulant raw material for water and wastewater treatment. The chemical synthesis follows a Mannich reaction mechanism and provides a fully working coagulant that can remove several pollutants from water. This paper addresses the optimization of such synthesis and confirms the feasibility of the coagulant by testing it in a preliminary screening for the elimination of dyes and detergents. The optimum combination of reagents was 6.81 g of diethanolamine (DEA) and 2.78 g of formaldehyde (F) per g of tannin extract. So obtained coagulant was succesfully tested on the removal of 9 dyes and 8 detergents.

Influence of drinking water with quebracho tannin on intake of endophyte-infected tall fescue by cattle

Endophyte-infected tall fescue (TF) contains alkaloids that can adversely affect the productivity and health of livestock. These effects are exacerbated when livestock forage on TF grown in monoculture, but they are mitigated when livestock forage on pastures that contain TF in mixture with tannin-containing plants, evidently because tannins bind to the steroidal and protein-like alkaloids found in TF. Cattle and sheep will drink water that contains up to 20g/L condensed tannins. We hypothesized that cattle (n=8) offered water containing quebracho tannins (10g/L) would eat more TF than cattle (n=8) offered plain water. During the trial, cattle were offered 9kg/(animal*d) of freshly harvested TF. Cattle drank less water with than without tannins (17.7kg/d vs. 24.6kg/d; P<0.005), and they tended to eat less TF (4.3kg/d vs. 5.1kg/d; P=0.10). No differences in weight change occurred during the trial (P=0.83) or between groups (P=0.70). The negative impacts of tannins on water intake likely depressed intake of TF, but the lower intakes of tannin water and TF did not adversely affect BW. On the one hand, water restriction and dehydration reduce food intake and any agent that limits intake of water will adversely affect food intake and animal performance. On the other hand, while cattle with fresh water maintained BW during the trial, so did cattle with tannin water, which suggests the tannin may have benefited the cattle fed a diet of orchard grass hay and TF. Further studies are required to assess the role of tannins in water on both the intake and performance of livestock eating TF.

Fast Pressing Composite Using Tannin-Furfuryl Alcohol Resin and Vegetal Fibers Reinforcement

Experimental investigations have been carried out on the potential use of tannin-furfuryl alcohol resin for biobased composites using vegetal fiber reinforcement. Results showed that a mixture containing 54% furfuryl alcohol, 45% modified quebracho extract and 0.9% paratoluenesulfonic acid as a catalyst yields a resin that can be used with a nonwoven flax fiber mat to manufacture lightweight composites with good mechanical properties and a very short curing time with a regular hot press. The panels made were tested for tensile and flexural modulus and strength, water resistance and thermo-degradation.

The quality of meat from sheep treated with tannin- and saponin-based remedies as a natural strategy for parasite control

Lambs were assigned to four groups of seven and treated as follows for 12days: control group (BP) was fed beet pulp; group T (tannin remedy) received the BP diet including 80g/kg of quebracho extract; group S (saponin remedy) received the BP diet including 15g/kg of quillaja extract; and group C had a free choice between T and S remedies. Lipid oxidation was lower in meat from S lambs compared to T lambs (P<0.05). Among the volatile compounds, lactate was lower in meat from S lambs compared to T animals (P=0.05). Metabolomic analysis showed that the T treatment increased ribose, fructose, glucose and sorbitol concentration in meat (P<0.05), while cholesterol was decreased by S and C treatments. The T treatment increased the concentration of C14:1 cis-9 (P<0.05). These findings indicate that treatments for parasite control containing tannins and saponins do not detrimentally affect sheep meat quality.

Antifungal properties of some plant extracts used as wood preservatives

This study evaluated antifungal resistance of some commercial and environmentally friendly plant extracts. Four different concentrations of mimosa (Acacia mollissima), quebracho (Schinopsis lorentzii) and pine (Pinus brutia) bark extracts known with their high condense tannin amounts were used to impregnate Scotch pine (Pinus sylvestris L.), beech (Fagus orientalis L.) and poplar (Populus tremula) wood specimens. Extract treated wood specimens were tested against two types of white rot fungi (Trametes versicolor and Pleurotus ostreatus) and two types of brown rot fungi (Fomitopsis palustris and Gloeophyllum trabeum) for 16 weeks. The lowest mass loss rates were recorded for mimosa and quebracho extract treated wood blocks at the 9% and 12% concentration levels against both white and brown rot fungi. Pine bark extract, on the other hand, seemed to be ineffective against all fungi species tested even at the highest concentration level (12%). The current study suggests that commercial mimosa and quebracho extracts can be utilized as alternative wood preservative chemicals against common wood decay fungi in indoor applications.

Preference for tannin-containing supplements by sheep consuming endophyte-infected tall fescue hay1,2

Tannins may bind to alkaloids in endophyte-infected (E+) tall fescue and attenuate fescue toxicosis. To test this hypothesis, thirty-two 4-mo-old lambs were randomly assigned to 4 treatments (8 lambs/treatment) in a 2 by 2 factorial design that included a basal diet of tall fescue hay [E+ or endophyte-free (E-)] supplemented with (TS) or without (CS) bioactive Quebracho tannins. The concentration of ergovaline in E+ fed in 2 successive phases was 65 ± 21 µg/kg (Phase 1) and 128 ± 4 µg/kg (Phase 2). After exposure to hays and supplements, all lambs were offered choices between TS and CS and between E+ and E- hays. During Phase 1, lambs offered E+ consumed more hay than lambs offered E- (P = 0.03). Lambs on E+/TS displayed the greatest intake of hay and the least intake of TS (P < 0.05). During Phase 2, when the concentration of ergovaline increased, lambs offered E+ consumed less hay than lambs fed E- (P < 0.0001). Lambs on E+/CS consumed less hay than lambs on E-/CS (P = 0.02), but hay intake by lambs on E-/TS and E+/TS did not differ (P = 0.96). Lambs preferred CS to TS during preference tests (P < 0.0001) and lambs on E+/TS ingested the least amounts of supplement TS and the greatest amounts of supplement CS (P = 0.001). Lambs offered E+ displayed greater body temperatures than lambs offered E- in both phases (P < 0.05). When offered a choice among the 3 hays, lambs previously exposed to E+ preferred E+ (low content of ergovaline) > E- > E+ (greater content of ergovaline; P < 0.001). Thus, decreased concentrations of ergovaline increased rectal temperatures, and affected intake of and preference for tannins and fescue hay. Quebracho tannins did not attenuate the effects of E+ on body temperature and feed intake. Ingestion of E+ reduced intake of quebracho tannins, suggesting that alkaloids in E+ antagonized ingestion of condensed tannins.

Improving the Dyeing Properties of Vegetable Tanned Leathers Using Chitosan Formate

This study examined the characteristics and dyeing fastness of sheep skins that had been tanned with two different vegetal tannins: hydrolysable tara and condensed quebracho tannins. After tanning, chitosan formate was applied to the leathers in four different proportions. The dye exhaustion and tensile strengths of the leathers increased as the proportion of chitosan formate increased, and the highest levels of both dye exhaustion and tensile strength were obtained in an application at a proportion of 200% on the basis of leather weight. Leathers treated with chitosan formate had slightly higher tensile strength values than the control leathers. In addition, chitosan formate was found to improve waste water parameters such as chemical oxygen demand, total suspended solids, total dissolved solids, salinity, and electrical conductivity.

Dietary quebracho tannins are not absorbed, but increase the antioxidant capacity of liver and plasma in sheep

A total of sixteen lambs were divided into two groups and fed two different diets. Of these, eight lambs were fed a control diet (C) and eight lambs were fed the C diet supplemented with quebracho tannins (C+T). The objective of the present study was to assess whether dietary quebracho tannins can improve the antioxidant capacity of lamb liver and plasma and if such improvement is due to a direct transfer of phenolic compounds or their metabolites, to the animal tissues. Feed, liver and plasma samples were purified by solid-phase extraction (SPE) and analysed by liquid chromatography-MS for phenolic compounds. Profisitinidin compounds were identified in the C+T diet. However, no phenolic compounds were found in lamb tissues. The liver and the plasma from lambs fed the C+T diet displayed a greater antioxidant capacity than tissues from lambs fed the C diet, but only when samples were not purified with SPE. Profisetinidin tannins from quebracho seem not to be degraded or absorbed in the gastrointestinal tract. However, they induced antioxidant effects in animal tissues.

Short- to medium-term effects of consumption of quebracho tannins on saliva production and composition in sheep and goats1

Eight Merino sheep (49.4 ± 4.23 kg BW) and 8 Alpine goats (53.2 ± 2.51 kg BW) were used to study the effect of ingestion of quebracho tannins on salivation. Four sheep and 4 goats were individually fed a daily allotment of 20 g DM of alfalfa hay/kg BW (Control). Another 4 sheep and 4 goats were also given 20 g DM of alfalfa hay/kg BW supplemented with 50 g of quebracho/kg DM (Tannin) for a period of 64 d. The saliva secretion from the left parotid gland was collected by insertion of a polyvinyl chloride catheter into the parotid duct and the amount of parotid saliva produced recorded over three 48-h periods on d 1 and 2 (P1), d 31 and 32 (P2), and d 61 and 62 (P3) after the tannin feeding was initiated. The total amount of saliva produced was estimated from rumen water kinetics determined on d 4, d 34, and d 64 of the experiment. Experimental design was completely randomized, with repeated measures on each experimental unit, performing separate analysis for sheep and goats. Parotid saliva production was not affected by the sampling period in either animal species receiving the Control diet. Corresponding values for sheep were 2.04, 2.12, and 2.27 L/d (P = 0.89) and for goats 1.65, 1.79, and 1.86 L/d (P = 0.95). Sheep fed the Tannin diet produced 55, 73, and 107% of the amount of saliva recorded in sheep fed the Control diet on P1, P2, or P3, respectively. Corresponding values in goats were 88, 130, and 134% on P1, P2, or P3, respectively. Estimated total saliva production was not affected (P = 0.50 for sheep and P = 0.97 for goats) by the ingestion of quebracho. There was no difference (P > 0.10) in osmotic pressure, P, Mg, Ca, urea, and protein concentrations in parotid saliva. There were, however, differences in Na and K concentrations in response to the ingestion of quebracho tannins, with Na concentrations increasing (P = 0.05) and K concentrations decreasing (P = 0.04) in sheep saliva and pH increasing (P = 0.05) in goat saliva. In conclusion, the inclusion of quebracho at 50 g/kg DM for 64 d does not appear to alter saliva production in sheep and goats.

Main binding sites involved in Fe(III) and Cu(II) complexation in humic-based structures

The main objective of this study is to investigate the more relevant binding sites (functional groups) involved in the complexation of Fe(III) and Cu(II) by humic-based structures. To this aim we have generated a set of seven humic-based samples (MHA) by the application of a hemi-synthetic process consisting in the oxidative polymerization of different combinations of three sources of natural organic molecules: two humic acids obtained from peat and leonardite, and natural tannin extracted from the quebracho tree (Schinopsis sp.) bark. These MHA were extensively characterized by using complementary analytical techniques (13C NMR, size-exclusion chromatography, electron paramagnetic resonance, and total phenol-reductant content), and their ability to complex Fe(III) and Cu(II) was also calculated by fluorescence quenching method. The data were studied by using general correlation matrix and principal component analysis.The results obtained, taken together, indicated that in a set of humic-based structures presenting carboxylic, phenol and O-alkyl groups, and diverse aliphatic/aromatic character, the complexation of Fe(III) mainly involved specific structural arrangements including carboxylic groups distributed in aliphatic domains. However, Cu(II) complexation involved singular structural arrangements including phenols (and probably substituted phenols) and O-alkyl groups in side chains of aromatic domains.

Cattle and sheep develop preference for drinking water containing grape seed tannin

Ingestion of small amounts of some types of condensed tannins (CTs) by ruminant livestock can provide nutritional, environmental and economic benefits. However, practical methods are needed to make these tannins more available to ruminant livestock. Results from previous trials with crude quebracho and black wattle tannin indicated that cattle and/or sheep would not preferentially drink water containing these tannins. Therefore, we conducted preference trials to determine if cattle and sheep would learn to prefer water containing purified grape seed tannin (GST) that provided up to 2% of their daily dry matter (DM) intake. After gradual exposure to increasing amounts of this tannin in water during a pre-trial period, five adult ewes and five yearling heifers fed lucerne (Medicago sativa) pellets (19% CP) were offered water and several concentrations of GST solutions for either 15 (sheep trial) or 20 days (cattle trial). We measured intake of all liquids daily. Concentrations of blood urea were also measured for heifers when they drank only tannin solutions or water. Both sheep and cattle developed preferences for water with GST in it over water alone (P < 0.01) although this preference appeared earlier in the trial for sheep than for cattle. For the sheep, mean daily intake of water alone and all tannin solutions (in total) was 0.6 and 6.1 l, respectively. For the cattle, mean daily intake of water and all tannin solutions in total was 21.8 and 20.6 l, respectively, in the first half of the trial and 10.8 and 26.1 l, respectively, in the second half of the trial. Compared with the other tannin solutions, both sheep and cattle drank more of the solution with the highest tannin concentration (2% of daily DM intake as GST) than of water on more trial days (P < 0.05). Ingestion of water with the highest concentration of GST reduced blood plasma urea concentration in the cattle by 9% to 14% (P ⩽ 0.10) compared with ingestion of water alone. Results from the trials suggest that providing grape seed and perhaps other CTs via drinking water may be a practical way to introduce CTs into sheep and cattle diets.