Hydrolysable Tannins Research Articles

Towards sustainable steel corrosion protection: expanding the applicability of natural hydrolyzable tannin in epoxy coatings via metal complexation

The study aimed to develop inhibitive pigments based on the natural biopolymer tannin through metal complexation, as an effective and eco-friendly alternative to conventional inhibitive pigments in epoxy coatings for steel protection in marine environments. Initial screening of metal cations for tannin complexation was conducted via steel immersion tests in 3.5 wt% NaCl solution. The combination of tannin with Zn2+ and Ce3+ both exhibited outstanding corrosion inhibition performance. After a 14-day immersion period, the inhibition efficiency reached 79.0 % and 74.0 % respectively, compared to 53.9 % for pure tannin. The more uniform formation of iron-tannin complexes and the co-deposition of metal hydroxides/oxides are believed to contribute to a synergistic effect, as confirmed by ATR-FTIR and SEM-EDS analysis. Further, considering both inhibition efficiency and eco-friendliness, the cerium(III)-tannin complex (CeTA) pigment was successfully synthesized and incorporated into anticorrosive epoxy coatings. Salt spray exposure and electrochemical impedance spectroscopy (EIS) measurements consistently demonstrated improved pigment compatibility with the epoxy matrix and reinforced coating anticorrosive performance.

A serine carboxypeptidase-like acyltransferase catalyzes consecutive four-step reactions of hydrolyzable tannin biosynthesis in Camellia oleifera.

Hydrolyzable tannins (HTs), a class of polyphenolic compounds found in dicotyledonous plants, are widely used in food and pharmaceutical industries because of their beneficial effects on human health. Although the biosynthesis of simple HTs has been verified at the enzymatic level, relevant genes have not yet been identified. Here, based on the parent ion-fragment ion pairs in the feature fragment data obtained using UPLC-Q-TOF-/MS/MS, galloyl phenolic compounds in the leaves of Camellia sinensis and C. oleifera were analyzed qualitatively and quantitatively. Correlation analysis between the transcript abundance of serine carboxypeptidase-like acyltransferases (SCPL-ATs) and the peak area of galloyl products in Camellia species showed that SCPL3 expression was highly correlated with HT biosynthesis. Enzymatic verification of the recombinant protein showed that CoSCPL3 from C. oleifera catalyzed the four consecutive steps involved in the conversion of digalloylglucose to pentagalloylglucose. We also identified the residues affecting the enzymatic activity of CoSCPL3 and determined that SCPL-AT catalyzes the synthesis of galloyl glycosides. The findings of this study provide a target gene for germplasm innovation of important cash crops that are rich in HTs, such as C. oleifera, strawberry, and walnut.

Intensification of bio-actives extraction from pomegranate peel via microwave irradiation: Effect of factors, optimization, kinetics, and bioactive profiling

Pomegranate (Punica granatum L.) peel is an appealing agri-food byproduct due to its high content of health-beneficial phytochemicals. However, the extraction processes may alter their bioactivity. A microwave irradiation treatment was applied to enhance the extraction efficiency. Extraction time, microwave power, and temperature were examined and optimized numerically using polynomial model and genetic algorithm. Time and temperature were the most influential factors in intensifying bioactives extraction. The optimal variables were 620 W microwave power at 74 °C for 18 min (RSM), and 685 W power at 75 °C for 24 min (ANN-GA). The obtained yields of total polyphenols, flavonoids, punicalagin, ellagic acid, and total hydrolyzable tannins contents were 165.53 mg GAE/g, 40.78 mg QE/g, 91.05 mg/g, 4.28 mg/g, and 130.82 mg TAE/g of pomegranate peel, respectively. The extract showed significant antioxidant capacities, with 65.74 % DPPH inhibition and 71.26 % ABTS inhibition. Several kinetic models were studied to define the extraction kinetics, with Peleg's model being the best fitting with the highest R2 (0.963–0.987) and lowest RMSE (0.95–5.08). LCMS analysis confirms the presence of 15 hydrolyzable tannins, with punicalagin and ellagic acid being the most abundant. These findings demonstrated the significant potential of microwave irradiation for extracting bioactives from fruit byproducts.

Investigating the efficacy of purified tannin extracts from underutilized temperate forages in reducing enteric methane emissions in vitro

The study investigated how the concentration and composition of purified tannin extracts, at various inclusion rates, affect the ruminal in vitro fermentation parameters. Tannin extracts were isolated from four different forage species: birdsfoot trefoil (Lotus corniculatus), sulla (Hedysarum coronarium), big trefoil (Lotus pedunculatus), and salad burnet (Sanguisorba minor). Plants extracts were purified by Sephadex LH-20 gel chromatography and analyzed by UPLC–ESI–MS/MS. The results showed a large variation among the extracts from different species in terms of tannin composition and structural features. The extracts from salad burnet were dominated by hydrolysable tannins, comprising mainly ellagitannins. The extracts derived from sulla and big trefoil contained predominantly proanthocyanidins (PA), primarily composed of prodelphinidins with high mean degree of polymerisation (mDP). Birdsfoot trefoil extracts comprised procyanidin-rich PAs with low mDP. To determine whether the combined presence of tannins and flavonoid together lead to synergistic or antagonistic effects, the tannin extracts were incubated both with or without rutin at concentrations of 10, 20, and 30 g/kg DM, using a base substrate of perennial ryegrass (Lolium perenne, control). In general, all the tannin extracts decreased methane (CH4) production compared to the control, while no significant effect of rutin was observed on both gas (GP) and CH4 production, neither pure, nor in the simultaneous presence of tannins. The highest CH4 reduction (15%, at 30 g/kg DM) was observed from sulla and big trefoil extracts compared to control, but this was also supplemented with a concomitant reduction in GP (11%) indicating a reduction in feed digestibility. The extracts from birdsfoot trefoil and salad burnet reduced CH4 by up to 12% without significantly reducing GP, indicating the importance of tannin composition on ruminal fermentation.

Phytochemical profile and determination of cytotoxicity, acute oral toxicity, genotoxicity, and mutagenicity of aqueous and ethanolic extracts of Pseudobombax marginatum (A. St.-Hil.) A. Robyns

ABSTRACT Pseudobombax marginatum, popularly known as “embiratanha,” is widely used by traditional communities as anti-inflammatory and analgesic agent. This study aimed to determine the phytochemical profile as well as cytotoxicity, acute oral toxicity, genotoxicity, and mutagenicity attributed to exposure to aqueous (AqEx) and ethanolic (EtEx) extracts of embiratanha bark. Phytochemical screening was conducted using thin-layer chromatography (TLC). Cell viability was analyzed using MTT assay with human mammary gland adenocarcinoma (MDA-MB-231) and macrophage (J774A.1) cell lines, exposed to concentrations of 12.5, 25, 50, or 100 µg/ml of either extract. For acute oral toxicity, comet assay and micronucleus (MN) tests, a single dose of 2,000 mg/kg of either extract was administered orally to Wistar rats. TLC analysis identified classes of metabolites in the extracts, including cinnamic acid derivatives, flavonoids, hydrolyzable tannins, condensed tannins, coumarins, and terpenes/steroids. In the cytotoxicity assay, the varying concentrations of extracts derived from embiratanha induced no significant alterations in the viability of MDA-MB-231 cells. The lowest concentration of EtEx significantly increased macrophage J774A.1 viability. However, the higher concentrations of AqEx markedly lowered macrophage J774A.1 viability. Animals exhibited no toxicity in the parameters analyzed in acute oral toxicity, comet assay, and MN tests. Further, EtEx promoted a significant reduction in DNA damage index and DNA damage frequency utilizing the comet assay, while the group treated with AqEx exhibited no marked differences. Thus, data demonstrated that AqEx or EtEx of embiratanha may be considered safe at a dose of 2,000 mg/kg orgally under our experimental conditions tested.

Study on Quality Characteristic of Chebulae Fructus and Its Adulterants and Degradation Pathway of Hydrolyzable Tannins.

Chebulae Fructus (CF) is known as one of the richest sources of hydrolyzable tannins (HTs). In this study, ultra-performance liquid chromatography coupled with a photodiode array detector method was established for simultaneous determination of the 12 common phenolcarboxylic and tannic constituents (PTCs). Using this method, quantitative analysis was accomplished in CF and other four adulterants, including Terminaliae Belliricae Fructus, Phyllanthi Fructus, Chebulae Fructus Immaturus, and Canarii Fructus. Based on a quantitative analysis of the focused compounds, discrimination of CF and other four adulterants was successfully accomplished by hierarchical cluster analysis and principal component analysis. Additionally, the total contents of the 12 compounds that we focused on in this study were unveiled as 148.86 mg/g, 96.14 mg/g, and 18.64 mg/g in exocarp, mesocarp, and endocarp and seed of CF, respectively, and PTCs were witnessed to be the most abundant in the exocarp of CF. Noticeably, the HTs (chebulagic acid, chebulanin acid, chebulinic acid, and punicalagin) were observed to be ultimately degraded to chebulic acid, gallic acid, and ellagic acid during sunlight-drying of the fresh fruits. As a result, our study indicated that CF and its adulterants could be distinguished by the observed 12 PTCs, which were mainly distributed in the exocarp of the fruits. The HTs were prone to degrade into the three simple phenolcarboxylic acids during drying or processing, allowing us to obtain a more comprehensive understanding of the PTCs, with great significance in the improved quality of CF and related products.

Wound healing potential of a formula based on Populus nigra L. flower buds extract with anti-inflammatory activity

Ethnopharmacological relevanceWound healing is a complex and dysnamic process supported by a myriad of cellular events that are tightly coordinated to repair efficiently damaged tissue. Populus nigra L. (Salicaceae) flower buds are traditionally used in the treatment of dermatitis, upper respiratory tract infections, rheumatism and wounds. Aim of the studyThe aim of this study was to assess the wound healing potential of black poplar ointment containing 10 or 20 % of Populus nigra ethanolic flower buds extract using the excision model in rats. Materials and methodsTwo ointments (10 and 20 %) were prepared from Populus nigra flower buds ethanolic extract and topically applied on the area of excised skin of the rats for either 14 or 20 days. Morphological, macroscopic, histological and biochemical parameters were evaluated. ResultsThe results showed that the extract contained high amounts of total phenols (89.5 ± 7.7 mg caffeic acid equivalent/g of extract) and hydrolysable tannins (142.05 ± 2.55 mg tannic acid equivalent/g of extract), in correlation with strong DPPH (2,2-diphenyl-1-picrylhydrazyl) radical scavenging activity and beta-carotene bleaching with values of 96.31 ± 3.42 and 85.27 ± 1.79 %, respectively. Anti-inflammatory potential was illustrated by lipoxygenase and cyclooxygenase inhibition (52.80 ± 0.2 and 53.88 ± 2.55 %, respectively). Treatment with Populus nigra ointment (10 and 20 %) promoted wound contraction of 97.37 ± 1.19 and 97.28 ± 0.91 %, respectively. The antioxidant marker enzymes, catalase (0.10 ± 0.001; 0.08 ± 0.003 U/mg protein) and superoxide dismutase (363.34 ± 24.37; 317.82 ± 53.83 U/mg protein) activities in the granulation tissues were upgraded with respective treatments of 10 or 20 % ointment. Concurrently, the myeloperoxidase activity (2.21 ± 1.01; 2.13 ± 0.75 U/mg protein) was repressed, indicating anti-inflammatory potential, when compared to untreated, standard and excipient groups. Moreover, a significant increase in respective levels of hydroxyproline (p < 0.001) (28.05 ± 1.20; 25.29 ± 1.17 μg/mg tissue) and hexosamine (p < 0.05) (20.18 ± 1.21; 18.95 ± 1.98 μg/mg tissue) was triggered, reflecting a high regeneration of collagen in the scarred tissue. Histological examination of treated skin tissue revealed higher rates of re-epithelialization, lower neutrophils infiltration and re-vascularization in comparison to the control group. ConclusionGiven that the 10 % ointment was the optimal concentration, our findings offer an efficient drug formula for wound healing.

Development of a New Extraction Method for Pomegranate and Metabolite Profiling by a LC-MS and 1H NMR Combined Approach.

The pomegranate (Punica granatum L.) market has steadily grown due to the increasing demand of health-conscious consumers of products with health-promoting effects. Recently, a growing interest in developing ecological and environmentally friendly extraction methods has led to investigating extraction procedures to obtain a higher extraction yield using a lower amount of solvents and energy. Herein, a new extraction procedure was developed to obtain an enriched pomegranate food supplement by using the peels of pomegranate, cultivar "Dente di Cavallo" and its juice. The extraction was performed through a non-conventional extraction technique like SLDE-Naviglio using ethanol and pomegranate juice as a solvent, and peels as a matrix. The extract was analysed by a combined approach based on LCESI/QExactive/MS/MS and NMR analysis, and its chemical profile was compared with those of pomegranate juice and of the extract obtained from peels by SLDE-Naviglio by using ethanol:H2O. The LC-MS analysis highlighted the presence of hydrolysable tannins, flavonoids, ellagic acid and phenol glucoside derivatives, while 1H NMR analysis completed the profile by detecting the primary metabolites. The LC-MS and 1H NMR analysis indicated that the extract obtained by SLDE-Naviglio using ethanol and pomegranate juice was enriched in the bioactives as confirmed by the highest phenolic, tannin and flavonoid content.

Rapid production of abundant transgenic pomegranate (Punica granatum) hairy roots

Pomegranates (Punica granatum) are known for their high levels of health-beneficial compounds that belong to the hydrolyzable tannin (HT) and flavonoid families. However, a significant gap in our understanding exists of the biosynthetic and regulatory genes related to the accumulation of these compounds. To this end, the induction and transformation of hairy roots presents an exciting opportunity to decipher genetically the functions of candidate genes involved in the HT and flavonoid metabolism. This study aims at improving methods for rapid and abundant hairy root production from pomegranate explants by increasing seed germination rates and expediting the attainment of requisite biomass for multifaceted analyses. We found that treating seeds with sandpaper and concentrated sulfuric acid significantly enhanced their germination rates. Interestingly, no correlation between seed-coat texture and seed germination rate was observed among the 20 pomegranate accessions evaluated in this study. Notably, transferring hairy roots from agar plates to soil promoted rapid root biomass growth compared to maintaining them on agar plates. Root biomass as well as levels of gallic acid (a precursor for HT biosynthesis) and punicalagins (the major HTs in roots) across 15 pomegranate accessions were also analyzed. Three of these accessions exhibited higher seed germination percentages along with augmented biomass and elevated punicalagin levels. These pomegranate accessions emerge as promising germplasm for future genetic transformation and functional genomics studies.

Total Content and Composition of Phenolic Compounds from Filipendula Genus Plants and Their Potential Health-Promoting Properties.

This current article was dedicated to the determination of the composition of phenolic compounds in extracts of four species of the genus Filipendula in order to establish a connection between the composition of polyphenols and biological effects. A chemical analysis revealed that the composition of the extracts studied depended both on the plant species and its part (leaf or flower) and on the extractant used. All four species of Filipendula were rich sources of phenolic compounds and contained hydrolyzable tannins, condensed tannins, phenolic acids and their derivatives, and flavonoids. The activities included data on those that are most important for creating functional foods with Filipendula plant components: the influence on blood coagulation measured by prothrombin and activated partial thromboplastin time, and on the activity of the digestive enzymes (pancreatic amylase and lipase). It was established that plant species, their parts, and extraction methods contribute meaningfully to biological activity. The most prominent result is as follows: the plant organ determines the selective inhibition of either amylase or lipase; thus, the anticoagulant activities of F. camtschatica and F. stepposa hold promise for health-promoting food formulations associated with general metabolic disorders.

Unveiling the metabolites underlying the skin anti-ageing properties of Cytinus hypocistis (L.) L. through a biochemometric approach

The genus Cytinus, recognised as one of the most enigmatic in the plant kingdom, has garnered attention for its bioactive potential, particularly its skin anti-ageing properties. Despite this recognition, much remains to be accomplished regarding deciphering and isolating its most active compounds. This study aimed to identify the compounds responsible for C. hypocistis skin anti-ageing potential. Using multivariate analysis, a biochemometric approach was applied to identify the discriminant metabolites by integrating extracts' chemical profile (Liquid Chromatography-High-Resolution Mass Spectrometry, LCHRMS) and bioactive properties. The identified bioactive metabolite was structurally elucidated by 1D and 2D Nuclear Magnetic Resonance (NMR). Among the studied bioactivities, the anti-elastase results exhibited a significant variation among the samples from different years. After the biochemometric analysis, the compound 2,3:4,6-bis(hexahydroxydiphenoyl)glucose, with a molecular mass of 784.075 Da, was structurally elucidated as the discriminant feature responsible for the outstanding human neutrophil elastase inhibition. Remarkably, the subfraction containing this compound exhibited a tenfold improvement in neutrophil elastase inhibition efficacy compared to the crude extract; its effectiveness fell within the same range as SPCK, a potent irreversible neutrophil elastase inhibitor. Moreover, this subfraction displayed no cytotoxicity or phototoxicity and excellent efficacy for the tested anti-ageing properties. Hydrolysable tannins were confirmed as the metabolites behind C. hypocistis skin anti-ageing properties, effectively mitigating critical molecular mechanisms that influence the phenotypically distinct ageing clinical manifestations. Pedunculagin was particularly effective in inhibiting neutrophil elastase, considered one of the most destructive enzymes in skin ageing.

Effect of Polyphenols Isolated from Plantago major L. and Plantago lanceolata L. on Mitochondrial Permeability Transition Pore in Rat Liver

It has been shown that the transport of electrons in the respiratory chain of mitochondria, ion-transport processes, the balance of Ca2+ ions and other metabolic processes in the cell are intrinsically connected with lipoperoxidation processes. In particular, in recent years, plant biologically active compounds have been widely used to eliminate oxidative processes developing in the body. Accordingly, we considered it important to study the mechanisms of action of xylopyr-T, glucopyr-T and 2-DVG polyphenols isolated from the plants Plantago major L. and Plantago lanceolata L., belonging to the Plantaginaceae family, which are widely used in folk medicine. Therefore, in vitro experiments, the amount of malondialdehyde and the condition state of mPTP were studied by spectrophotometric method. The obtained results revealed that the studied polyphenols inhibit lipoperoxidation induced by Fe2+/ascorbate the production of malondialdehyde was reduce by xylopyr-T to 81.9 ± 1.2 %, by glucopyr-T to 79.4 ± 1.7 % and by 2-DVG to 75.0 ± 1.8 % at a concentration of 4 µM in rat liver mitochondria. At the same time, mPTP opening in the medium with the substrate succinate (+ rotenone) inhibition 2-DVG polyphenol at a concentration of 100 μM was reduced by 84.5 ± 2.8 %, xylopyr-T polyphenol at a concentration of 200 μM by 67.6 ± 4.8 % and it was shown that glucopyr-T polyphenol at a concentration of 200 µM by 32.5 ± 1.65 % compared to the control. In conclusion, it can be illustrated that the studied polyphenols, along with their high antioxidant properties, show a structure-dependent inhibition of mPTP opening, which is involved in various physiological and pathological processes. HIGHLIGHTS In this study, hydrolysable tannins, which have strong antioxidant properties isolated from Plantago plants, were investigated and confirmed by MDA analysis in vitro These hydrolyzable tannins exhibited substrate-dependent inhibition of rat liver mitochondrial PTP in vitro It can be assumed from the data obtained that these hydrolyzable tannins act organ-specifically GRAPHICAL ABSTRACT

Anti-inflammatory effect of Anadenanthera colubrina var. cebil (Griseb.) Altschul in experimental elastase-induced pulmonary emphysema in rats

Ethnopharmacological relevanceMedicinal plants have shown promise in the search for new treatments of pulmonary emphysema. Anadenanthera colubrina, a species native to the Caatinga biome in northeastern Brazil, is widely recognized and traditionally employed in the treatment of pulmonary diseases. Many studies corroborate popular knowledge about the medicinal applications of A. colubrina, which has demonstrated a remarkable variety of pharmacological properties, however, its anti-inflammatory and antioxidant properties are highlighted. Aim of the studyThe objective of this study was to investigate the anti-inflammatory potential of the crude hydroethanolic extract of A. colubrina var. cebil (Griseb.) Altschul on pulmonary emphysema in rats as well as to determine its potential genotoxic and cytotoxic effects using the micronucleus assay. Materials and methodsThe stem bark of the plant was collected in Pimenteiras-PI and sample was extracted by maceration using 70% ethanol. A portion of the extract underwent phytochemical analyses using TLC and HPLC. In this study, 8-week-old, male Wistar rats weighing approximately ±200 g was utilized following approval by local ethics committee for animal experimentation (No. 718/2022). Pulmonary emphysema was induced through orotracheal instillation of elastase, and treatment with A. colubrina extract or dexamethasone (positive control) concomitantly during induction. Twenty-eight days after the initiation of the protocol, plasma was used for cytokine measurement. Bronchoalveolar lavage (BAL) was used for leukocyte count. After euthanasia, lung samples were processed for histological analysis and quantification of oxidative stress markers. The micronucleus test was performed by evaluating the number of polychromatic erythrocytes (PCE) with micronuclei (MNPCE) to verify potential genotoxic effects of A. colubrina. A differential count of PCE and normochromatic erythrocytes (NCE) was performed to verify the potential cytotoxicity of the extract. Parametric data were subjected to normality analysis and subsequently to analysis of variance and Tukey or Dunnett post-test, non-parametric data were treated using the Kruskal-Wallis test with Dunn's post-test for unpaired samples. P value < 0.05 were considered significant. ResultsThe A. colubrina extract did not show a significant increase in the number of MNPCE (p > 0.05), demonstrating low genotoxicity. No changes were observed in the PCE/NCE ratio of treated animals, compared with the vehicle, suggesting low cytotoxic potential of the extract. A significant reduction (p < 0.05) in neutrophilic inflammation was observed in the lungs of rats treated with the extract, evidenced by presence of these cells in both the tissue and BAL. The extract also demonstrated pulmonary antioxidant activity, with a significant decrease (p < 0.05) in myeloperoxidase, malondialdehyde, and nitrite levels. TNFα, IL-1β, and IL-6 levels, as well as alveolar damage, were significantly reduced in animals treated with A. colubrina extract. Phytochemical analyses identified the presence of phenolic compounds and hydrolysable tannins in the A. colubrina extract. ConclusionsThe findings of this study highlights the safety of the hydroethanolic extract of Anadenanthera colubrina, and demonstrates its potential as a therapeutic approach in the treatment of emphysema. The observed properties of this medicinal plant provide an optimistic outlook in the development of therapies for the treatment of pulmonary emphysema.

Heterogeneity of transport and metabolism of Tormentillae rhizoma constituents across human intestinal epithelium cellular model

Tormentilla erecta (L.) Raeusch is a widespread plant in Europe and Western Asia. Its rhizomes (Tormentilae rhizoma) are the main ingredient of herbal alcoholic beverages and can be used as a natural preservative in beer production. Apart from its unique taste qualities, therapeutic properties in gastrointestinal tract ailments are attributed to the tincture obtained from Tormentillae rhizoma. The presented research aimed to determine the mutual relationship between the components of Tormentillae tincture, present in popular alcoholic beverages, and intestinal epithelium (Caco-2 cell monolayers). A comprehensive qualitative and quantitative analysis of the tincture was performed, including the determination of condensed and hydrolyzable tannins as well as triterpenoids (UHPLC-DAD-MS/MS). Incubation of the tincture with Caco-2 monolayers has shown that only triterpenes pass through the monolayer, while condensed tannins are mainly bound to the monolayer surface. Ellagic acid derivatives were the only components of the Tormentillae tinctura being metabolized by cell monolayers to the compounds not previously described in the literature, which may be crucial in the treatment of intestinal diseases with inflammatory background.

In Vivo Behavior of Hydrolyzable Tannins after Oral Administration of the Trapa bispinosa Extract to Rats.

The pericarp extract of Trapa bispinosa (TBPE), which is rich in hydrolyzable tannins, has been reported to inhibit α-glucosidase and glycation reactions. We investigated the in vivo behavior of hydrolyzable tannins and related metabolites after administration of TBPE to rats. Using high pressure liquid chromatography-electrospray ionization-tandem mass spectroscopy (HPLC-ESI-MS/MS), 12 ellagitannin metabolites, such as urolithins and 6 gallotannin metabolites, produced in the collected plasma and urine were quantified. Urolithins and gallic acid metabolites reached their maximum blood concentration after 24 and 1 h of administration, respectively. Conversely, the excretion of urolithins in urine required up to 72 h and followed a sigmoidal curve, whereas gallic acid metabolites were rapidly excreted earlier after administration. The results suggest that the metabolites gallotannin and ellagitannin are responsible for the antiglycation effect of TBPE, which proceeds via different mechanisms and times. Our findings provide basic data demonstrating the functionality of hydrolyzable tannins as well as Trapa ingredients.

Effect of supplementation of bioactive rich tree leaves on nutrient utilization, growth performance, methane emission and fatty acid profile in finisher lambs fed energy dense diet

To study the effect of supplementing bioactive rich tree foliages in energy dense diet on lamb production and tissue fatty acid profile, 24 weaner male lambs (∼90days old) were divided equally into 2 groups and fed complete feed blocks without (C) and with 6% Hardwickia binata (anjan tree) leaves (T). Feed blocks in both the groups consisted of 3.25% rumen bypass fat. Dry matter intake and plane of nutrition were comparable among the groups but digestibility of neutral and acid detergent fibre were lower (P<0.05) in T than C. Rumen fermentation attributes revealed higher (P<0.05) concentration and proportion of propionic acid and total volatile fatty acids in T compared to C. The metagenomic equivalent values of total methanogens and protozoa were lower (P<0.05) while, population of Butyrivibrio fibrisolvens was higher in T compared to C. Loss of metabolizable energy through methane was reduced by 4.6 percentage points in T than C which resulted in higher microbial nitrogen synthesis in T from methane mitigation. Subsequently, the average daily gain in lambs was improved by 5.9% in T compared to C. The fatty acid profile of Longissimus thoracis muscle revealed higher (P<0.05) C18:2c9t11 content in lambs of T group than C. Hence, from the present findings it can be concluded that inclusion of Hardwickia binata leaves at 6% level increased condensed and hydrolysable tannin content of the diet which modestly affected rumen fermentation resulting in reduced methane production and enhanced conjugated linoleic acid content in muscle tissue.

UV-C-induced changes in a white wine: Evaluating the protective power of hydrolysable tannins and SO&lt;sub&gt;2&lt;/sub&gt;

UV‑C treatment is a non-thermal technology that could be used for the microbiological stabilisation of must and wine. However, light - in this case UV‑C light - has an impact on wine. UV‑C is a high-energy light source and can promote photo-induced oxidation reactions. The formation of reactive oxygen species during the UV-C treatment of wine can be prevented via supplementation with antioxidants. These have the ability to neutralise reactive oxygen species or directly interact with the products of photo-induced oxidation reactions. This study investigates the impact of different UV‑C doses on the chemical and sensory characteristics of Chardonnay wine and examines the protective effect of two antioxidants: sulphur dioxide (SO2) and hydrolysable tannins. A sensory evaluation revealed that UV‑C doses higher than 1 kJ/l increased the colour intensity and the oxidised and burnt odour attributes of the wine. The peach odour attribute decreased with UV‑C treatment. On a chemical level, increasing UV‑C doses promoted the formation of compounds such as acetaldehyde and 2‑aminoacetophenone (2‑AAP), while causing the degradation of C13‑norisoprenoids, higher alcohols, monoterpenes and esters. Contrary to expectations, SO2 did not act as an antioxidant when wine was treated with UV-C. It intensified the burnt odour attribute and did not mitigate the intensity of the oxidised odour attribute, which can be explained by the formation of acetaldehyde. However, hydrolysable tannins acted as antioxidants when combined with UV‑C treatment, effectively mitigating the formation of 2‑AAP and acetaldehyde, while preventing the wine from becoming oxidised.

Atlas pistachio (Pistacia atlantica) unripe fruit extract as a source of phytochemicals with anti-tyrosinase, antioxidant, and antibacterial properties

The current need for biologically active substances that are sustainable, allegedly beneficial to health, and may be employed as ingredients in cosmetic products has encouraged numerous researchers. Pistacia atlantica is known to contain compounds that possess strong biological effects beneficial to health. The objective of this study was the quantification of the polyphenols in unripe Atlas pistachio (AP) fruit extract and the evaluation of hydro-methanolic extract and anthocyanins for their antioxidant, anti-tyrosinase, and antimicrobial effects. The results revealed that the yield of the hydro-methanolic extract was 22.15%, characterized by 75.12 mg GAE/g DM for total phenolics and strong content of hydrolysable tannins (400.16 mg GAE/g DM). 1,1-dimethyl-allyl caffeate, hydroxytyrosol, ellagic acid, rutin, and kaempferol-3-O-glucoside were the most abundant components quantified by HPLC-DAD. The tyrosinase enzyme was significantly inhibited by AP extract (EC50 = 0.70 mg/mL). For the antioxidant properties, the hydrolyzed anthocyanin extract exhibited the best action against reducing power and β-carotene, compared to anthocyanins crude extract and fruits. This extract showed its stronger antibacterial activity. In conclusion, unripe AP fruit is a promising source of diverse phytochemicals that can be applied in medicinal, nutraceutical, and cosmetic applications as antioxidants and antimicrobials.

Plant Protection by Tannins Depends on Defence-Related Phytohormones

AbstractPlants produce a wide variety of secondary metabolites to sustain and protect themselves against a wide range of stresses. Among these metabolites, tannins are one of the most abundant polyphenolic compounds, accounting for 25% of the dry weight of leaves, roots and bark of woody plants, but are also abundant in flowering and seed-producing plants. The presence of tannins in these organs serves to protect plants against herbivorous and pathogenic attack through their antidigestive and antimicrobial properties. In addition, tannins play a role in regulating plant growth and development by inhibiting the consumption of unripe fruits due to their astringency. In addition, several studies have also revealed various roles of them under environmental stresses. Tannins can be classified into condensed tannins (CTs), hydrolysable tannins (HTs) and phlorotannins. They are synthesised in plants via the acetate–malonate and shikimic acid pathways. Their accumulation is regulated by several transcription factors during normal development and under different stress conditions. Despite their multiple roles in plant life, information on the regulation of tannin metabolism by defence-related phytohormones is very limited. To cope with biotic and abiotic stresses, plant responses are regulated by defence-related phytohormones such as salicylic acid (SA), jasmonic acid (JA), ethylene (ET) and abscisic acid (ABA), which act as regulators of tannin production under adverse conditions. This review focuses on tannin production, moreover its occurrence, defence potential and regulation by phytohormones under different environmental and biotic stresses, based on the most recent and relevant data. Graphical Abstract

Genomic basis of the distinct biosynthesis of β-glucogallin, abiochemical marker for hydrolyzable tannin production, inthree oak species.

Hydrolyzable tannins (HTs), predominant polyphenols in oaks, are widely used in grape wine aging, feed additives, and human healthcare. However, the limited availability of a high-quality reference genome of oaks greatly hampered the recognition of the mechanism of HT biosynthesis. Here, high-quality reference genomes of three Asian oak species (Quercus variabilis, Quercus aliena, and Quercus dentata) that have different HT contents were generated. Multi-omics studies were carried out to identify key genes regulating HT biosynthesis. Invitro enzyme activity assay was also conducted. Dual-luciferase and yeast one-hybrid assays were used to reveal the transcriptional regulation. Our results revealed that β-glucogallin was a biochemical marker for HT production in the cupules of the three Asian oaks. UGT84A13 was confirmed as the key enzyme for β-glucogallin biosynthesis. The differential expression of UGT84A13, rather than enzyme activity, was the main reason for different β-glucogallin and HT accumulation. Notably, sequence variations in UGT84A13 promoters led to different trans-activating activities of WRKY32/59, explaining the different expression patterns of UGT84A13 among the three species. Our findings provide three high-quality new reference genomes for oak trees and give new insights into different transcriptional regulation for understanding β-glucogallin and HT biosynthesis in closely related oak species.