Quebracho Tannin Research Articles

Phytochemical analysis and antioxidant activity of Mezzetia parviflora Becc. Woodbark extract

Context: The woodbark of Mezzefia parviflora Becc. (Annonaceae) used as traditional herbal remedies in Buton Regency, Southeast Sulawesi, Indonesia, which is traditionally used for tumor, asthma, cholesterol, and diabetes mellitus. The diseases have been linked to cellular damages due to free radical activity. Aims: The present study was aimed to examine the antioxidant activity of M. parviflora; furthermore to ascertain the physicochemical identity and major compound that responsible for extract's quality and activity. Methods and Material: The ethanolic extract of M. parviflora and its partition results which are acetone extract and insoluble in acetone extract were studied for antioxidant activity on different in vitro models namely 1,1-diphenyl-2-picrylhydrazyl (DPPH) and nitric oxide (NO) method. Ascorbic acid was also evaluated for comparison. Thin layer chromatography and acid-buthanol assay were used to detect the presence of phenolic compounds. Results: All of the extracts were effectively scavenge the DPPH radical. The IC50 of insoluble in acetone extract, ethanolic extract, and acetone extract were 21.79, 30.22, 60.73, and 262.55 μg/ml, respectively. The insoluble in acetone extract show greater DPPH radical scavenging than ascorbic acid (IC50 30.22 μg/ml). Meanwhile, the extracts showed low scavenging activities on NO radical with IC50 of insoluble in acetone extract, and ethanolic extract were 229.09, and 316.23 μg/ml, respectively. The high percentage of phenolic condensed tannin in the insoluble in acetone extract i.e 26.46±0.315 μg/mg of extract (calculated as quebracho tannin) justify the potent antioxidant activity. Conclusions: Woodbark extracts of Mezzefia parviflora Becc. has potent antioxidant activity which is related to their condensed tannin content.

Effect of the inclusion of quebracho tannins in a diet rich in linoleic acid on milk fatty acid composition in dairy ewes

Despite controversy surrounding the ability of tannins to modulate the fatty acid (FA) profile of ruminant-derived products, reports on this issue are still very limited for dairy sheep. This study was conducted to examine the effect of the inclusion of quebracho tannins in a diet rich in linoleic acid on ewe performance and milk FA composition. Thirty-six lactating ewes were distributed into 6 lots and allocated to 2 treatments (3 lots/treatment): control or quebracho. All sheep received a total mixed ration based on alfalfa hay and a concentrate (forage:concentrate ratio of 40:60) supplemented with 20g of sunflower oil/kg of dry matter plus 0 (control diet) or 20g of an extract of quebracho tannins/kg of dry matter (QUE diet). Milk production and composition were analyzed on d 0, 3, 6, 9, 12, 15, 18, 21, 24, and 27 on treatments, and milk FA profile on d 0, 3, 6, 12, 18, and 27. On d 27, samples of rumen fluid were collected for pH, and lactate, ammonia, and volatile FA concentration analysis. Feeding the QUE diet had no apparent effect on animal performance and hardly modified ruminal fermentation characteristics, except for a reduction in the molar proportions of minor volatile FA. Dietary tannins increased the milk concentration of several 18:1 and 18:2 isomers and decreased that of branched-chain FA. Some of these changes were relatively constant throughout the experiment (e.g., cis-12 18:1 and trans-9,cis-12 18:2), whereas others varied over time (e.g., trans-10 18:1, which increased gradually with the QUE diet). Significant differences between treatments in trans-11 18:1 and cis-9,trans-11 conjugated linoleic acid were only observed on d 3. Overall, addition of quebracho tannins to a diet rich in linoleic acid did not prove useful to beneficially modify milk FA composition, especially over the long term.

Inhibition of hydrogen sulfide, methane, and total gas production and sulfate-reducing bacteria in in vitro swine manure by tannins, with focus on condensed quebracho tannins

Management practices from large-scale swine production facilities have resulted in the increased collection and storage of manure for off-season fertilization use. Odor and emissions produced during storage have increased the tension among rural neighbors and among urban and rural residents. Production of these compounds from stored manure is the result of microbial activity of the anaerobic bacteria populations during storage. In the current study, the inhibitory effects of condensed quebracho tannins on in vitro swine manure for reduction of microbial activity and reduced production of gaseous emissions, including the toxic odorant hydrogen sulfide produced by sulfate-reducing bacteria (SRB), was examined. Swine manure was collected from a local swine facility, diluted in anaerobic buffer, and mixed with 1% w/v fresh feces. This slurry was combined with quebracho tannins, and total gas and hydrogen sulfide production was monitored over time. Aliquots were removed periodically for isolation of DNA to measure the SRB populations using quantitative PCR. Addition of tannins reduced overall gas, hydrogen sulfide, and methane production by greater than 90% after 7days of treatment and continued to at least 28days. SRB population was also significantly decreased by tannin addition. qRT-PCR of 16S rDNA bacteria genes showed that the total bacterial population was also decreased in these incubations. These results indicate that the tannins elicited a collective effect on the bacterial population and also suggest a reduction in the population of methanogenic microorganisms as demonstrated by reduced methane production in these experiments. Such a generalized effect could be extrapolated to a reduction in other odor-associated emissions during manure storage.

Effect of dietary protein level and quebracho tannin on consumption of pine needles (Pinus ponderosa) by beef cows

<h2>ABSTRACT</h2> Ponderosa pine trees occupy over 15 million hectares of rangeland in western North America. Pregnant cows often consume pine needles (PN), and subsequently abort. The protein-to-energy ratio may be important in the ability of cattle to tolerate dietary terpenes. Tannins often co-occur with terpenes and may also influence diet selection. The objective of this experiment was to determine if the protein-to-energy ratio or the addition of quebracho tannin to cattle diets would influence PN consumption. In trial 1, 15 cows in moderate body condition were assigned to high (15.4% CP), medium (10.2% CP), or low (4.9% CP) dietary protein treatments for 12 d. In trial 2, 15 cows were assigned to high (5%), medium (2.5%), or no (0%) quebracho tannin diets for 8 d. In both trials, green PN were offered at 0930 h for 90 min. There was a treatment effect (P = 0.05) and a treatment × day interaction (P = 0.01) for PN consumption, as cattle on the high CP treatment consumed more PN than cattle on the medium and low CP diets for 4 and 6 d, respectively. Initially, treatments did not differ (P > 0.09), but from d 3 to 9 cattle on the high CP treatment ate more PN than the other treatments. There was a day × treatment interaction (P = 0.002) for PN consumption; cattle on the 2.5% tannin treatment consumed less PN than did animals on the other treatments. Cattle are apparently unable to tolerate high quantities of PN terpenes on a low-protein diet. Tannins may influence PN consumption, but the mechanism is unknown.

Effects of adding protein, condensed tannins, and polyethylene glycol to diets of sheep and goats fed one-seed juniper and low quality roughage

The biochemical mechanisms that limit voluntary intake of one-seed juniper by browsing ruminants are not well understood. Twelve Rambouillet ewes (78±2.3kgBW) and 12 Boer-Spanish does (54±1.4kgBW) were used in a split-plot sequence design to investigate the effects of adding protein, quebracho tannins (QTs), and polyethylene glycol (PEG) on one-seed juniper intake and preference and on ruminal VFA and plasma AA concentrations. Animals received sudangrass hay and isoenergetic basal diets (4 does and 4 ewes/diet) with either rumen degradable (RDP) or rumen undegradable (RUP) protein (12.5% CP) or no additional protein (control, 5% CP) during four 15-d periods. The control, RDP, and RUP diets were considered the main plot, whereas the four supplement treatments were analyzed as the split-plot effects. Period 1 allowed for adaptation to basal diets and served as a baseline phase. In periods 2–4, animals were offered juniper leaves and twigs (period 2), juniper plus QT (10% of basal diet; period 3), and juniper plus QT plus PEG (50g/animal; period 4). Juniper intake by sheep and goats was not affected (P>0.88) by RDP or RUP when animals were first exposed to juniper, but marginally increased (P<0.10) in period 4 (QT+PEG) regardless of the basal diet. Prior exposure to juniper did not affect (P=0.61) the preference ratio for juniper, but goats had higher preference ratio for juniper (P<0.01) when receiving PEG (period 4). Concentrations of total VFA tended to increase in sheep (P=0.10) and goats (P=0.14) fed protein supplements and molar proportions shifted toward acetate for goats fed RDP and RUP (P=0.07) and to butyrate for sheep fed RDP (P=0.01). Initial juniper exposure (period 2) elevated concentrations of acetate, propionate, and butyrate (P<0.01), but the effect was extinguished in periods 3 and 4 with addition of QT (P<0.05). Supplementation with PEG transiently mitigated the depressor effect of QT on acetate, propionate, and butyrate concentration at 12h post juniper feeding (P<0.01). RDP in goats and to a greater extent RUP in sheep increased plasma concentrations of various AA, especially the branched chained Val, Ile, and Leu (P<0.05). Plasma concentrations of several AA, including Met, Cyst, Glu, Gly, Gln, Asn, Thr, Ser, and Phe, decreased with ingestion of juniper (period 2) and juniper plus QT (period 3). Concentrations of some AA that were depressed by ingestion of juniper and QT were partially restored with supplemental PEG (P<0.05). Protein, terpenes, tannins, and PEG interacted to influence rumen VFA and plasma AA, which were related to intake of juniper and basal diets.

Assessment of the effect of condensed (acacia and quebracho) and hydrolysable (chestnut and valonea) tannins on rumen fermentation and methane production in vitro

Tannins added to animal diets may have a positive effect on energy and protein utilisation in the rumen. The objective of this study was to examine the impact of different sources and concentrations (20, 50, 100, 150 and 200 g kg⁻¹ dry matter (DM)) of condensed (acacia and quebracho) and hydrolysable (chestnut and valonea) tannins on rumen microbial fermentation in vitro. The experiment also included a negative control with no tannins (control) and a positive control with monensin (10 mg L⁻¹). In vitro gas production and total volatile fatty acid (VFA) concentration decreased as tannin concentration increased. Addition of acacia, chestnut or valonea tannins at ≥ 50 g kg⁻¹ or quebracho tannins at ≥ 100 g kg⁻¹ resulted in a decrease (up to 40%) in methane (CH₄) production compared with the control. Valonea tannins were the only tannin source that reduced (-11%) CH₄ production at 50 g kg⁻¹ without affecting VFA concentration. Tannin treatments reduced ammonia (NH₃) and branched-chain VFA concentrations, indicating a reduction in ruminal protein degradation. Monensin reduced CH₄ production (-37%) and NH₃ concentration (-20%) without affecting total VFA concentration. Supplying acacia, chestnut or valonea tannins at 50 g kg⁻¹ has the potential to reduce CH₄ production and ruminal protein degradation with minimum detrimental effects on efficiency of ruminal fermentation.

Termiticidal properties of some wood and bark extracts used as wood preservatives

The feasibility of using naturally extracted solutions as wood preservative chemical was tested. Extracts extracted from mimosa (Acacia mollissima Willd.), quebracho (Shinopsis lorentzii Griseb.), and Pinus brutia Ten. bark were used to treat sapwood of Scotch pine (Pinus sylvestris L.), beech (Fagus orientalis L.), and poplar (Populus tremula L.) at two different retention levels (6% and 12% weight/weight) against the subterranean termite Reticulitermes grassei Clement (Blattodea: Rhinotermitidae). The lowest mass loss and highest termite mortality rates were recorded for mimosa and quebracho extract treated woods at the 12% concentration level. Pine bark extract seemed to be ineffective as a wood preservative chemical even at the highest retention level. The results suggest that mimosa and quebracho extracts can be utilized as an environmentally-sound alternative wood preservative chemicals for indoor applications against Reticulitermes grassei.

Bactericidal effect of hydrolysable and condensed tannin extracts on Campylobacter jejuni in vitro

Strategies are sought to reduce intestinal colonisation of food-producing animals by Campylobacter jejuni, a leading bacterial cause of human foodborne illness worldwide. Presently, we tested the antimicrobial activity of hydrolysable-rich blackberry, cranberry and chestnut tannin extracts and condensed tannin-rich mimosa, quebracho and sorghum tannins (each at 100mg/mL) against C. jejuni via disc diffusion assay in the presence of supplemental casamino acids. We found that when compared to non-tannin-treated controls, all tested tannins inhibited the growth of C. jejuni and that inhibition by the condensed tannin-rich mimosa and quebracho extracts was mitigated in nutrient-limited medium supplemented with casamino acids. When tested in broth culture, both chestnut and mimosa extracts inhibited growth of C. jejuni and this inhibition was much greater in nutrient-limited than in full-strength medium. Consistent with observations from the disc diffusion assay, the inhibitory activity of the condensed tannin-rich mimosa extracts but not the hydrolysable tannin-rich chestnut extracts was mitigated by casamino acid supplementation to the nutrient-limited medium, likely because the added amino acids saturated the binding potential of the condensed tannins. These results demonstrate the antimicrobial activity of various hydrolysable and condensed tannin-rich extracts against C. jejuni and reveal that condensed tannins may be less efficient than hydrolysable tannins in controlling C. jejuni in gut environments containing high concentrations of amino acids and soluble proteins.

Depression of rumen ammonia and blood urea by quebracho tannin-containing supplements fed after high-nitrogen diets with no evidence of self-regulation of tannin intake by sheep

The aim of this study was to assess whether sheep enhance nitrogen use in response to tannin supplementation, and if they increase preference for tannin-rich supplements when consuming diets high in rumen-degradable protein. In Experiment 1 twenty four Corriedale crossbred wethers (10 months of age; 41±2.1kg) were randomly divided into two groups (n=12/group). Group 1 received a high-protein basal diet of high rumen-degradable protein (“HP”), whereas the other group received a low-protein basal diet of low rumen-degradable protein (“LP”). During Period 1 (12 days) half of the animals from each group received a wheat bran supplement containing 11% quebracho tannins (T) and the other half had the same supplement but without tannins (NT). Wethers fed supplements T or NT during Period 1 received NT or T, respectively, during Period 2. Rumen fluid and jugular blood samples were collected on the last day of each period to determine ruminal ammonia nitrogen and blood urea nitrogen (BUN) concentration, respectively. Experiment 2 was similar to Experiment 1, except that a new set of wethers was used (11 months of age; 41±2.4kg), oat straw replaced wheat bran, and only BUN was determined. After Period 2 of Experiment 2, all animals had a simultaneous offer of T and NT and preference for T was estimated for 3 days. In Experiment 1, wethers in HP consumed greater (P<0.05) amounts of basal diet than wethers in the LP during Period 1. Wethers exposed to HP displayed lower values of BUN and ruminal ammonia nitrogen when consuming T than when ingesting NT (Periods 1 and 2, respectively; P<0.01). In Experiment 2, wethers under the HP diet and supplemented with T consumed the greatest amounts of basal diet (Period 1; P<0.05). Intake of tannin was higher in LP than in HP (P<0.05) and wethers exposed to HP displayed lower values of BUN when consuming T than when ingesting NT (Period 2; P<0.05). Preference for and intake of the tannin-containing food tended (P=0.11) to be greater for wethers exposed to HP than for wethers under LP during the last day of testing. Tannin supplements have the potential to reduce rumen ammonia nitrogen and BUN in sheep, even when fed after ingestion of high-N diets and in the form of low-quality supplements.

Identification of oenological tannins extracted from oak wood

Our study is dealing with the determination of the origin of oenological tannins using the modified OIV procedure. The method is based on HPLC analyses of proanthocyanidol content (catechin, epicatechin, epigallocatechin, epicatechin-3-O-gallate and epigallocatechin-3-O-gallate) after thioacidolysis - thiolytic cleavage of the flavonol intermonomer linkages in proanthocyanidols under heat in an acid medium. The purpose of the study was to differentiate oenological tannins gained from Quebracho cortex and tannins extracted from oak wood. As the results show, both groups of tannins do not produce any flavan-3-ols after thioacidolysis, but they show specific peaks, which enable determination of their origin.

Effect of catechins and tannins on depleted uranium-induced DNA strand breaks

The effects of polyphenols on plasmid DNA strand breaks by depleted uranium were studied using four catechins: (+)-catechin, (−)-epicatechin, (−)-epigallocatechin (EGC), and (−)-epigallocatechin gallate (EGCG); seven tannins: Chinese gallotannin, persimmon tannin (PST), mimosa tannin (MMT), myrobalan tannin, quebracho tannin, gambir tannin, and chestnut tannin; and gallic acid. The plasmid DNA strand breaks by uranyl ion (UO22+) with hydrogen peroxide (H2O2) were strongly enhanced by EGC, EGCG, MMT, and PST (condenced tannins). The obtained results showed that the DNA strand breaks are caused by UO22+ through the direct interaction between the uranyl complex and the negatively charged DNA phosphate backbone. The additional DNA strand breaks by the addition of polyphenols occurred through an indirect process by the reduction of UO22+ to UO2+ and hydroxyl radical formation through a Fenton-type reaction with H2O2.

The quantification of condensed tannins in African savanna tree species

We compared Quebracho with Sorghum tannin as standards for condensed tannin (CT) quantification in selected African savanna tree species in relation to the acid-butanol assay for CTs. Without exception, the use of Quebracho tannin as standard overestimated CTs, ranging from 0.7 to as much as 8.3 times. Sorghum tannin underestimated CTs by 0.26–0.79 times, except in one species where there was no difference in the CT concentration. Condensed tannins in African savanna trees showed qualitative and quantitative differences in chemical composition which may explain the variable reactivity in the acid-butanol assay. We propose the use of condensed tannins purified from the plant under investigation be used as standard since it will closely represent the CT structure and presumably chemical reactivity in the acid-butanol assay.

Early experience with diverse foods increases intake of nonfamiliar flavors and feeds in sheep1,2

This study determined whether early experiences by sheep with monotonous or diverse diets influence intake of unfamiliar flavors and feeds later in life. Thirty 2-mo-old lambs were randomly assigned to 3 treatment diets (n = 10): diverse (DIV), diverse with plant toxins (DIV+T), and monotonous (MON). Lambs in DIV received in 9 successive periods of exposure 4-way choice combinations of 2 foods high in energy and 2 foods high in protein from an array of 6 foods: 3 high in energy [beet pulp, oat grain, and a mix of milo:grape pomace (60:40)] and 3 high in digestible protein (DP) (soybean meal, alfalfa, corn gluten meal). Lambs in DIV+T received the same exposure as DIV, but 2 plant toxins, oxalic acid (1.5%) and quebracho tannins (10%), were randomly added to 2 of the feeds in each of the choice combinations. Lambs in MON received a monotonous balanced diet, made with a mixture of all 6 feeds detailed before. All treatments received their feed in 4 separate buckets. During exposure, treatments did not differ in total daily DMI (P = 0.31), but daily intake of ME was less (P < 0.02) and daily intake of DP was greater (P < 0.03) for lambs in DIV and DIV+T than for lambs in MON. Treatments did not differ in ADG or G:F (P > 0.05). After exposure, lambs were offered a familiar feed (wheat bran) containing novel flavors (maple, garlic, or bitter) and 2-way choices of novel feeds (fescue hay vs. corn distillers grains, rice vs. calf manna, and green peas vs. rolled oats). Intake of maple-flavored wheat bran tended (P = 0.08) to be greater for lambs in DIV than for lambs in DIV+T and MON. Intake of bitter-flavored and garlic-flavored wheat bran were greater (P = 0.03 and P = 0.04, respectively) for lambs in DIV and DIV+T than for lambs in MON. During 2-way choice trials, lambs in DIV, but not in DIV+T, showed greater intakes of fescue hay (P = 0.05) and rice (P = 0.04) than lambs in MON. Intake of green peas was greater (P = 0.03) for lambs in DIV and DIV+T than for lambs in MON. At the end of testing, lambs in DIV but not in DIV+T showed greater ADG than lambs in MON (P = 0.05). Thus, early exposure to diverse foods enhanced acceptance of novel flavors relative to early exposure to a monotonous ration. Early experience with diverse feeds plus plant toxins led to a less diverse diet than early experience with diverse feeds. Early exposure to diverse feeds may be beneficial in production systems that require rapid acceptance and high intake of unfamiliar feeds.

Preference for condensed tannins by sheep in response to challenge infection with Haemonchus contortus

Herbivores prefer feeds that supply required nutrients and avoid those with excess nutrients and plant secondary compounds (PSC). Nevertheless, PSC such as condensed tannins can provide beneficial medicinal effects to herbivores as they act against infective diseases such as parasitism. The objectives of this study were to determine: (1) if parasitized lambs increased preference for a tannin-rich feed after they experienced the beneficial antiparasitic effects of condensed tannins relative to parasitized lambs that did not experience such benefits, and (2) if preference for the tannin-rich feed in the former group decreased when parasite burdens subsided. Twenty two lambs were familiarized with beet pulp and beet pulp+8% quebracho tannins (beet pulp+tannins) and choices were given between the two feeds (initial preference tests). Subsequently, all animals were dosed with 10,000 L3 stage larvae of Haemonchus contortus. Twenty-two days later, animals were exposed to beet pulp (Control group; n=11) or beet pulp+tannins (Treatment group; n=11) during 24d. After exposure (during a parasitic infection) animals in both groups were given choices between the two feeds. Lastly, animals in both groups received an antiparasitic drench and were again given a choice between both feeds (after a parasitic infection). Lambs preferred beet pulp to beet pulp+tannins throughout the study (P<0.001) and no difference in preference for the tannin-rich feed was detected between groups during initial preference tests (P>0.05). However, during a parasitic infection, intake of and preference for the tannin-rich feed was higher for lambs that experienced the beneficial effects of condensed tannins while parasitized (Treatment) than for lambs that did not (Control) (P<0.05). When parasitic infections were terminated by chemotherapy, differences between groups disappeared (P>0.05). Preference by the Treatment group for the tannin-rich feed was lower after than during a parasite infection (P<0.05). In contrast, preference by the Control group did not change during these periods (P>0.05). Lambs in the Treatment group displayed lower FEC than lambs in the Control group (Group×Sampling Date; P<0.05). These results show lambs learned about the antiparasitic effects of condensed tannins and increased their preference for the tannin-rich feed, which subsided after chemotherapy, indicating preference was due to parasite infection. These findings suggest management that allows animals to select tannin-rich feeds can enable parasitized animals to self-medicate.

Condensed Tannins Inhibit House Fly (Diptera: Muscidae) Development in Livestock Manure

Reducing chemical use for suppressing internal and external parasites of livestock is essential for protecting environmental health. Although plant condensed tannins are known to suppress gastro-intestinal parasites in small ruminants, no research on the effects of tannins on external arthropod populations such as the house fly, Musca domestica L., have been conducted. We examined the impact of plant material containing condensed tannins on house fly development. Prairie acacia (Acacia angustissima (Mill.), Kuntze variety hirta (Nutt.) B.L. Rob.) herbage, panicled tick-clover (Desmodium paniculatum (L.) DC.) herbage, and quebracho (Shinopsis balansae Engl.) extracts were introduced at rates of 1, 3 or 5% condensed tannins/kg beef cattle, dairy cattle, and goat manure, respectively. In a second experiment, we also introduce purified catechin at 1 or 3% of dairy manure dry matter and measured its impact on house fly development. For the house flies used in these experiments, the following was recorded: percent fly emergence (PFE), average daily gain (ADG), and average fly weight (AFW). No effects (P>0.05) in house fly development were measured in the caprine manure. Prairie acacia (20.9% condensed tannins) had no effect on house flies developing in either bovine manures. Tick clover (4.9% condensed tannins) had a negative effect on all three quantifiable variables of house fly development in the bovine manures, whereas quebracho extract (64.0% condensed tannins) at the 3 and 5% rate reduced fly emergence in beef manure and average daily gain in dairy manure. The application of purified catechin at 3%, but not 1%, reduced fly PFE, ADG, and AFW.

Analysis of commercial proanthocyanidins. Part 1: The chemical composition of quebracho ( Schinopsis lorentzii and Schinopsis balansae) heartwood extract

Quebracho ( Schinopsis lorentzii and Schinopsis balansae) extract is an important source of natural polymers for leather tanning and adhesive manufacturing. We combined established phyto- and synthetic chemistry perspectives with electrospray mass spectrometry experiments to prove that quebracho proanthocyanidin polymers consist of an homologous series of flavan-3-ol based oligomers. The starter unit is always catechin which is angularly bonded to fisetinidol extender units. By comparison of the MS 2 fragmentation spectra of the oligomer with product ion scans of authentic catechin and robinetinidol samples, we proved that quebracho extract contains no robinetinidol, as is often reported. Quebracho proanthocyanidins have acid resistant interflavanyl bonds, due to the absence of 5-OH groups in fisetinidol, and the aDP cannot be determined via conventional thiolysis and phloroglucinolysis. We used the MS data to estimate a conservative (minimum value) aDP of 3.1.

Novel Microwave-Assisted Synthesis of Nickel/Carbon (Ni/C) Nanocomposite with Tannin as the Carbon Source

Metal/carbon nanocomposites find use in many potential applications, in areas such as batteries, catalysts, inks, polymer additives, and solar cells. Nickel/carbon nanocomposites are widely used as heterogeneous catalysts in oil processing and other catalytic reactions. Here we describe a novel microwave-assisted synthesis of nickel/carbon nanocomposites, achieved within a few minutes, starting from nickel salts and a renewable high-content carbon source, tannin. The carbon precursor is Quebracho tannin, which is a renewable-resource material obtained from the hot-water extraction of Schinopsis lorentzii and Schinopsis balansae, which are indigenous to Argentina and Paraguay. The process involves a simultaneous carbonization of the carbon precursor as well as the reduction of nickel ions to elemental nickel nanoparticles in an ambient atmosphere. Thus, this technique provides a fast, easy, and economical way to produce nickel/carbon nanocomposites without requiring the need for hydrogen or inert gas during the transformation. This technique could be used to synthesize a wide range of other metal/carbon nanocomposites and therefore holds tremendous economic promise. The nanocomposites have a high surface area and may be suitable as high efficiency catalysts.

Condensed Tannin in Drinking Water Reduces Greenhouse Gas Precursor Urea in Sheep and Cattle Urine

Abstract Ingestion of small amounts of condensed tannin (CT) by ruminants may provide benefits including reduction of ammonia and nitrous oxide emissions by reducing urine urea excretion. However, providing grazing ruminants with sufficient amounts of CT-containing forages is difficult, and an alternative may be to provide CT in their drinking water. We conducted three trials to determine if urine urea levels in sheep and cattle decrease after they drink water containing CT. In two initial trials, blood serum urea was measured as a surrogate for urine urea when lambs or steers drank tap water containing low to higher amounts of quebracho tannin (QT). Serum urea concentration was measured after lambs drank the treatments for 7 d or steers for 4–6 d. Lambs consumed pellets (16% crude protein [CP] as fed) at 3.5% of body weight, and steers were fed cubes (15% CP as fed) at 3% of body weight. Mean serum urea concentration in sheep was reduced when they consumed water with QT ( P = 0.03) and was also reduced for cattle ( P P = 0.03). Reductions in daily urea excretion as a percentage of nitrogen intake were 3.5%, 6.6%, and 12.6%, respectively, for the low, medium, and high QT intake. Small amounts of QT in the drinking water of grazing ruminants can reduce their urine urea excretion.

Chemical composition of rumen microbial fraction and fermentation parameters as affected by tannins and saponins using an in vitro rumen fermentation system

Castro-Montoya, J. M., Makkar, H. P. S. and Becker, K. 2011. Chemical composition of rumen microbial fraction and fermentation parameters as affected by tannins and saponins using an in vitro rumen fermentation system. Can. J. Anim. Sci. 91: 433–448. Post-rumen chemical composition of the microbial fraction is one of the factors that determines the nutrients absorbed and available for maintenance and production of the animal. The hypothesis was that tannins and saponins alter chemical composition of rumen microbes and fermentation parameters in the rumen. Purified quebracho, mimosa, chestnut and sumach tannins; and quillaja and gypsophilla saponins were incubated with 380 mg of substrate (hay:concentrate 70:30 wt/wt) for 24 h in an in vitro gas production system at concentrations from 0.25 to 1.25 mg mL−1. Saponins increased N and reduced sugar contents of the liquid-associated microbes. The ratio of crude protein to purine bases significantly increased on adding sumach and chestnut tannins and decreased on the addition of quebracho and mimosa tannins. Quebracho, mimosa and chestnut tannins reduced total short-chain fatty acid production. The acetate:propionate ratio decreased for all additives. Results suggest that in vitro (a) depending on the source and the concentration, tannins would have an effect on the nitrogen and sugar contents of the liquid associated microbes, (b) saponins are likely to increase N and reduce sugar contents of rumen liquid associated microbes, and (c) estimation of microbial protein synthesis based on purine bases may lead to under- or over-estimations in the presence of tannins and saponins. In vivo studies are required to validate these results.

Relationships between early experience to dietary diversity, acceptance of novel flavors, and open field behavior in sheep

This study determined whether early experiences by sheep to monotonous or diverse diets influence: (1) plasmatic profiles of cortisol, a hormone involved in stress responses by mammals, before and after an ACTH challenge, (2) the readiness to eat new foods in a new environment, (3) general fearfulness and response to separation – as measured by the open field test (OFT) and stress induced hyperthermia (SIH) – and (4) the link between (2) and (3). Thirty, 2-mo-old lambs were randomly assigned to 3 treatments (10 lambs/treatment). Lambs in one treatment (Diversity — DV) received in successive periods of exposure all possible 4-way choice combinations of 2 foods high in energy and 2 foods high in protein from an array of 6 foods: 3 high in energy (beet pulp, oat grain, and a mix of grape pomace:milo [40:60]) and 3 high in protein (soybean meal, alfalfa, corn gluten meal). Lambs in another treatment (DV+T) received the same exposure described for DV but two phytochemicals, oxalic acid (1.5%) and quebracho tannins (10%) were randomly added within any period of exposure to foods high in energy or to foods high in protein. Lambs in the third treatment (Monotony — MO) received a monotonous balanced ration containing all 6 foods fed to the other groups. After exposure, lambs were offered a choice of the aforementioned 6 foods (DV; DV+T) or the monotonous diet (MO). Lambs were intravenously injected with ACTH 1h after food presentation, and sampled at 1, 2, and 3h post feeding for determinations of plasma cortisol concentrations. Reluctance to eat novel flavored foods (onion-, coconut- and cinnamon-flavored wheat bran), open field behavior, and SIH was assessed in all treatments. Lambs in MO showed greater concentrations of plasma cortisol 1h after food presentation than lambs in the DV or DV+T treatments (P=0.04). However, the difference was small and no differences among treatments were detected after an ACTH challenge (P>0.1). Lambs in DV consumed more onion-flavored wheat bran than lambs in MO (P=0.05). Lambs in DV also showed a greater cumulative consumption of novel flavors on d 2 than lambs in MO (treatment×day; P=0.01). Lambs in DV showed lower increase in rectal temperature (P=0.07) than lambs in MO. Only lambs in DV exhibited a positive relationship between consumption of cinnamon-flavored wheat bran and attempts of escape (R2=0.58; P=0.02). Our results suggest that exposure to diverse foods early in life may be less stressful than exposure to monotonous rations, as measured by plasma cortisol concentrations after food ingestion, and by changes in rectal temperature after exposure to the OFT. Lambs exposed to diverse diets early in life may also increase the initial acceptance of new flavors in novel environments relative to lambs exposed early in life to monotonous diets.