Tannin Production Research Articles

Genome-wide identification of TCP transcription factors and their potential roles in hydrolyzable tannin production in Quercus variabilis cupule.

Hydrolyzable tannins (HTs) have garnered significant attention due to their proven beneficial effects in the clinical treatment of various diseases. The cupule of Chinese cork oak (Quercus variabilis Blume) has been used as raw material of traditional medicine for centuries for its high content of HTs. Previous studies have identified UGT84A13 as a key enzyme in the HT biosynthesis pathway in Q. variabilis, but the transcriptional regulation network of UGT84A13 remains obscure. Here, we performed a comprehensive genome-wide identification of the TCP transcription factors in Q. variabilis, elucidating their molecular evolution and gene structure. Gene expression analysis showed that TCP3 from the CIN subfamily and TCP6 from the PCF subfamily were co-expressed with UGT84A13 in cupule. Further functional characterization using dual-luciferase assays confirmed that TCP3, rather than TCP6, played a role in the transcriptional regulation of UGT84A13, thus promoting HT biosynthesis in the cupule of Q. variabilis. Our work identified TCP family members in Q. variabilis for the first time, and provided novel insights into the transcriptional regulatory network of UGT84A13 and HT biosynthesis in Q. variabilis, explaining the reason why the cupule enriches HTs that could be used for traditional medicine.

Tannin Extraction in Coconut Shell Powder (Cocodust) to Improve the Quality of Cocopeat and Obtain Tannin Products

Tannin Extraction in Coconut Shell Powder (Cocodust) to Improve the Quality of Cocopeat and Obtain Tannin Products

Assessment of chemically modified vegetable tannins as coagulants for water treatment

This research assessed the efficiency of chemically modified tannins as coagulants for water treatment. Tannins from Anacardium occidentale (cashew tree) and Mimosa caesalpiniifolia (‘sabiá’) barks and seedless fruits of Anadenanthera colubrina (‘angico’) and Pityrocarpa moniliformis (‘angico de bezerro’) were evaluated after cationization to remove turbidity from water. After extraction, the total solids content (TSC), Stiasny index (SI), and total condensed tannins content (TCC) of the tannins extracts were determined. Extracted tannins were converted into powders and cationized. Then, the cationized tannins' effectiveness on water turbidity removal, sedimentation time, and effect on pH were assessed. Three concentrations of each type of tannin were used to evaluate flocculant efficiency: 50, 100, and 150 mg L-1. Although the P. moniliformis extract had a higher TSC value (56.06%), it presented the lowest SI (0.42%) and TTC (0.23%) values. M. caesalpiniifolia had the lowest TSC (9.18%) and the highest SI (91.27%), while Ac occidentale stood out with the highest TCC (19.83%). All species have shown potential for tannin production and efficiently removed turbidity at all concentrations. However, only A. occidentale, at a concentration of 100 mg L-1, presented a nephelometric turbidity unit of 2.4, reaching the potability standards required by international specifications and, therefore, being indicated for water treatment. Keywords: condensed tannins, forest species, natural flocculants, turbidity removal.

Identification and analysis of novel recessive alleles for Tan1 and Tan2 in sorghum.

The identification and analysis of allelic variation are important bases for crop diversity research, trait domestication and molecular marker development. Grain tannin content is a very important quality trait in sorghum. Higher tannin levels in sorghum grains are usually required when breeding varieties resistant to bird damage or those used for brewing liquor. Non-tannin-producing or low-tannin-producing sorghum accessions are commonly used for food and forage. Tan1 and Tan2, two important cloned genes, regulate tannin biosynthesis in sorghum, and mutations in one or two genes will result in low or no tannin content in sorghum grains. Even if sorghum accessions contain dominant Tan1 and Tan2, the tannin contents are distributed from low to high, and there must be other new alleles of the known regulatory genes or new unknown genes contributing to tannin production. The two parents 8R306 and 8R191 did not have any known recessive alleles for Tan1 and Tan2, and it was speculated that they probably both had dominant Tan1 and Tan2 genotypes. However, the phenotypes of two parents were different; 8R306 had tannins and 8R191 had non-tannins in the grains, so these two parents were constructed as a RIL population. Bulked segregant analysis (BSA) was used to determine other new alleles of Tan1 and Tan2 or new Tannin locus. Tan1 and Tan2 full-length sequences and tannin contents were detected in wild sorghum resources, landraces and cultivars. We identified two novel recessive tan1-d and tan1-e alleles and four recessive Tan2 alleles, named as tan2-d, tan2-e, tan2-f, and tan2-g. These recessive alleles led to loss of function of Tan1 and Tan2, and low or no tannin content in sorghum grains. The loss-of-function alleles of tan1-e and tan2-e were only found in Chinese landraces, and other alleles were found in landraces and cultivars grown all around the world. tan1-a and tan1-b were detected in foreign landraces, Chinese cultivars and foreign cultivars, but not in Chinese landraces. These results implied that Tan1 and Tan2 recessive alleles had different geographically distribution in the worldwide, but not all recessive alleles had been used in breeding. The discovery of these new alleles provided new germplasm resources for breeding sorghum cultivars for food and feed, and for developing molecular markers for low-tannin or non-tannin cultivar-assisted breeding in sorghum.

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.

Effects of leaf herbivory and autumn seasonality on plant secondary metabolites: A meta-analysis.

Plant secondary metabolites (PSMs) are produced by plants to overcome environmental challenges, both biotic and abiotic. We were interested in characterizing how autumn seasonality in temperate and subtropical climates affects overall PSM production in comparison to herbivory. Herbivory is commonly measured between spring to summer when plants have high resource availability and prioritize growth and reproduction. However, autumn seasonality also challenges plants as they cope with limited resources and prepare survival for winter. This suggests a potential gap in our understanding of how herbivory affects PSM production in autumn compared to spring/summer. Using meta-analysis, we recorded overall production of 22 different PSM subgroups from 58 published papers to calculate effect sizes from herbivory studies (absence to presence) and temperate to subtropical seasonal studies (summer to autumn), while considering other variables (e.g., plant type, increase in time since herbivory, temperature, and precipitation). We also compared production of five phenolic PSM subgroups - hydroxybenzoic acids, flavan-3-ols, flavonols, hydrolysable tannins, and condensed tannins. We wanted to detect a shared response across all PSMs and found that herbivory increased overall PSM production in herbaceous plants. Herbivory was also found to have a positive effect on individual PSM subgroups, such as flavonol production, while autumn seasonality was found to have a positive effect on flavan-3-ol and condensed tannin production. We discuss how these responses might stem from plants producing some PSMs constitutively, whereas others are induced only after herbivory, and how plants produce metabolites with higher costs only during seasons when other resources for growth and reproduction are less available, while other phenolic PSM subgroups serve more than one function for plants and such functions can be season dependent. The outcome of our meta-analysis is that autumn seasonality changes some PSM production differently from herbivory, and we see value in further investigating seasonality-herbivory interactions with plant chemical defense.

Fruitlet Thinning Improves Juice Quality in Seven High-tannin Cider Cultivars

Over 3 years (2016–18), tree productivity, biennial bearing, return bloom, and fruit quality were evaluated for seven high-tannin cider apple (Malus ×domestica Borkh.) cultivars. Five treatments were evaluated on each of the seven cultivars: hand-thinned of all fruit (a zero crop load treatment); hand-thinned to crop densities of three, six, or nine fruit/cm2 trunk cross-sectional area (TCSA); or left unthinned. In this paper, we report on the fruit maturity and juice quality properties that were analyzed for the three nonzero crop load treatments and the unthinned control. The effects of crop load on fruit maturity, as measured by starch pattern index and preharvest drop, were cultivar dependent. Crop density (fruit/cm2 TCSA) had a significant effect on all fruit maturity and juice quality variables, although effects were weakest in the “off” year (2017) for the whole planting when initial fruit set was low. As crop density increased, total poly phenols, titratable acidity, soluble solids, and primary amino nitrogen decreased in the juice of all seven cultivars. A partial budget analysis indicated that the reduced costs of nitrogen supplements due to increased primary amino nitrogen concentration alone would not justify cost of chemical or hand-thinning. By extrapolating the spring flowering density in the fourth year to potential fruit yields at harvest, we found that reducing crop load was projected to increase cumulative total polyphenol yields per tree over the long term. For the cultivars in this experiment, a target crop density of nine fruit/cm2 was found to adequately decrease biennial bearing while also not diminishing juice quality for hard cider production. High-tannin cider apple growers should consider juice quality, particularly tannin production, when making crop load management decisions.

Evaluation of the Economic, Environmental, and Social Impact of the Valorization of Grape Pomace from the Wine Industry.

The increase in the world population has led to intensive food production systems that are generating increasing amounts of solid waste. In this work, the valorization of the most important waste generated during wine production, grape pomace, is evaluated. Eight processes are proposed to approach different types of valorization (production of energy and value-added products), from economic, environmental, and social points of view. The best process depends on the budget available, the production capacity, and the weight of each impact produced by the factory (economic, environmental, or social). For small (less than 0.1 kg/s) or very large (greater than 10 kg/s) capacities, the production of high-value-added products outperforms the other processes in all three impacts and in profitability. For intermediate capacities, combustion and gasification stand out as having the highest greenhouse emissions and intermediate economic benefits. Anaerobic digestion is remarkable for its low greenhouse gas emissions, while tannin production is the best-balanced process from both economic and environmental points of view. Pyrolysis is the worst process of all three impacts.

In vitro production of steroidal saponin, total phenols and antioxidant activity in callus suspension culture of Paris polyphylla Smith: an important Himalayan medicinal plant.

Paris polyphylla Smith (Melanthiaceae) family, which is native to the Himalayan region, has received a lot of attention recently due to its extensive history of usage in traditional medicine. The production of steroidal saponin from callus suspension cultures of P. polyphylla was observed in the current study. The current study attempted to develop a P. polyphylla plant callus suspension culture through optimization of cultivation technique for callus suspension, quantification of total phenolic components and estimation of the extract's antioxidant activity. A light-yellow callus was formed within six weeks of cultivating rhizomes on Murashige and Skoog (MS) media supplemented with Thidiazuron (TDZ). Furthermore, the effect of TDZ, Methyl Jasmonate (MeJA), and Yeast Extract (YE) on callus growth, steroidal saponin (dioscin and diosgenin), total phenolic content, total flavonoids, total tannin, and total antioxidant activity was also measured. The medium containing 0.5 μM TDZ depicted the maximum callus biomass (2.98 g fresh weight). Significantly high phenolic and tannin content was observed in the MS medium containing 50 μM MeJA, whereas, no significant increase was observed in total tannin production in any treatment. Three in vitro assays, DPPH (2,2-diphenyl-1-picrylhydrazyl), ABTS (2,2'-azino-bis (3-ethylbenzothiazoline- 6-sulfonic acid)) and FRAP (ferric ion reducing antioxidant potential) and FC (Folin-Ciocalteu), were used to assess antioxidant potential of callus. Maximum antioxidant analysis reported in 1.0 μM TDZ (6.89 mM AAE/100 g) containing medium followed by 50 μM MeJA (6.44 mM AAE/100g). The HPLC analysis showed a high presence of dioscin and diosgenin (5.43% and 21.09%, respectively) compared to the wild sample (2.56% and 15.05%, respectively). According to the results, callus produced on media supplemented with 50 μM MeJA have significant phenolic contents and elevated antioxidant activity; nevertheless, callus growth was greater in the presence of 0.5 μM TDZ. The findings of the current study have commercial implications since greater biomass production will result in active phytochemicals that the pharmaceutical and nutraceutical sectors are in need desperately.

Fabrication of “Lysine modified Zein- Punica granatum peels’ purified ellagitannin nanoconjugates (Ly-M-Z-PE NCs)” and in-vitro bio-accessibility, antiproliferative activity, and biosafety studies

Pomegranate (punica garanatum) peels' ellagitannins exhibit remarkable health-beneficial properties. In the current work, lysine-modified, zein-based, pomegranate peels’ purified ellagitannin nanoconjugates were fabricated. The dynamic light scattering and field emission scanning electron microscopy findings demonstrated that pH (3, 5, 7, 9, and 11) has a significant effect on particle size, zeta potential, and shape of the nanoconjugates. It was found that a near-neutral pH (6.8–7) was ideal for fabricating the conjugated nanoparticles with reduced particle sizes (174.33 nm), homogeneous size distribution (0.1), and a good net charge (−25.53 mv). In these conditions, it demonstrated good particle production (83.83%) and binding effectiveness (83.23%) of total hydrolysable tannins. Transmission electron microscopy showed evenly dispersed spherical particles. Fourier transform infrared spectroscopy revealed conjugations between pure ellagitannins, and protein nanoparticles involving hydrogen bonding, hydrophobic interaction, and electrostatic contact. The synthesized nanoconjugates exhibited strong antioxidant scavenging capacity. Thermal stability, antibacterial activity, in vitro gastrointestinal bioaccessibility, and antiproliferative activity (liver cancer cells) were all improved by conjugation. The cytotoxic study of Lysine modified zein purified ellagitannin nanoconjugates showed no deleterious impact on normal Vero cell lines. Overall, our work shows that adding pure ellagitannin from pomegranate peels to protein nanoparticles is a cost-effective way to meet customer demand for safer, newer, healthier foods with better quality and uses.

EXTRACTION OF POLYPHENOLIC COMPOUNDS FROM THE JUGLANS REGIA L. PELLICLES OF USING ULTRASOUND

The attention of Russian and foreign scientists is focused on obtaining secondary plant metabolites, including phenolic compounds, due to their pharmacological activity. The Juglans regia L. pellicles are a promising raw source for the production of alkaloids, naphthoquinones (juglone), tannins and organic acids. In modern practice of obtaining biologically active substances from plant raw materials, intensive extraction methods are of particular interest. In this extraction method ultrasonic treatment is used to increase the yield and intensify the process of extracting biologically significant substances. Technological parameters of ultrasonic treatment must be selected individually for each type of plant raw material. The aim of the work was to study the effect of ultrasonic treatment on the yield of polyphenolic substances during extraction from the pellicles of breeding varieties Juglans regia L. It was found that the content of tannins in the pellicle biomass of the studied varieties Juglans regia L. varies from 5.2 to 7.3 g/100 g, phenolic compounds – from 17 to 18.2 mg/100 g. The highest content of these compounds was recorded in the pellicle biomass of the Valentina's Gift variety. It was found that ultrasonic treatment with a power of 200 W for 10 min contributes to the highest yield of polyphenolic substances in the extract from the pellicle biomass of the Valentina's Gift variety. However, the spectral profiles of hydroalcoholic extracts indicate the opposite: 200 W ultrasound reduces the intensity of the extraction of polyphenolic compounds.

Nutrient enrichment promotes invasion success of alien plants via increased growth and suppression of chemical defenses.

In support of the prediction of the enemy release hypothesis regarding a growth-defense trade-off, invasive alien plants often exhibit greater growth and lower anti-herbivory defenses than native plants. However, it remains unclear how nutrient enrichment of invaded habitats may influence competitive interactions between invasive alien and co-occurring native plants, as well as production of anti-herbivore defense compounds, growth-promoting hormones, and defense-regulating hormones by the two groups of plants. Here, we tested whether: (i) nutrient enrichment causes invasive alien plants to produce greater biomass and lower concentrations of the defense compounds flavonoids and tannins than native plants; and (ii) invasive alien plants produce lower concentrations of a defense-regulating hormone jasmonic acid (JA) and higher concentrations of a growth-promoting hormone gibberellic acid (GA3). In a greenhouse experiment, we grew five congeneric pairs of invasive alien and native plant species under two levels each of nutrient enrichment (low vs. high), simulated herbivory (leaf clipping vs. no-clipping), and competition (alone vs. competition) in 2.5-L pots. In the absence of competition, high-nutrient treatment induced a greater increase in total biomass of invasive alien species than that of native species, whereas the reverse was true under competition as native species benefitted more from nutrient enrichment than invasive alien species. Moreover, high-nutrient treatment caused a greater increase in total biomass of invasive alien species than that of native species in the presence of simulated herbivory. Competition induced higher production of flavonoids and tannins. Simulated herbivory induced higher flavonoid expression in invasive alien plants under low-nutrient than high-nutrient treatments. However, flavonoid concentrations of native plants did not change under nutrient enrichment and simulated herbivory treatments. Invasive alien plants produced higher concentrations of GA3 than native plants. Taken together, these results suggest that impact of nutrient enrichment on growth of invasive alien and co-occurring native plants may depend on the level of competition that they experience. Moreover, invasive alien plants might adjust their flavonoid-based defense more efficiently than native plants in response to variation in soil nutrient availability and herbivory pressure. Our findings suggest that large-scale efforts to reduce nutrient enrichment of invaded habitats may help to control future invasiveness of target alien plant species.

Genotype × Environment Interaction Influence Secondary Metabolite in Cowpea Infested by Flower Bud Thrips

Secondary metabolites are among the major contributors of host-plant resistance. Cowpea produces secondary metabolites that are known to enhance resistance to insect pests including flower bud thrips. However, environmental conditions tend to affect the production of secondary metabolites, thereby affecting the response of the host plants to insect pest. The objective of this study was to determine the effect of the genotype × environment interaction on the production of secondary metabolites and flower bud thrips resistance in cowpea. Six cowpea genotypes were evaluated for flower bud thrips damage and the contents of flavonoids, antioxidants, phenolics, proteins, lignin, tannins and reducing sugars in four environments with varying temperatures and rainfall patterns. The data collected were subjected to the analysis of variance and genotype and genotype × environment (GGE) analysis. Flower thrips damage, and the contents of flavonoids, antioxidants, lignin, tannins and reducing sugars varied significantly (p < 0.001) among genotypes. Genotype Sanzi produced high levels of antioxidants, while TVU-9820 led in phenolic concentrations respectively. Metabolite contents were significantly (p < 0.001) different among environments, with the long rain season of field experiments led to increased production of flavonoids, proteins, lignin and tannins. A resistant genotype, TVU-3804, produced relatively stable contents of flavonoids, antioxidants, phenolics, proteins and reducing sugars across environments. In this study, the environment influenced the concentration of the metabolites, which in turn affected the cowpea’s resistance to flower bud thrips.

LC-HRMS/MS-Based Metabolomics Approaches Applied to the Detection of Antifungal Compounds and a Metabolic Dynamic Assessment of Orchidaceae.

The liquid chromatography-mass spectrometry (LC-MS)-based metabolomics approach is a powerful technology for discovering novel biologically active molecules. In this study, we investigated the metabolic profiling of Orchidaceae species using LC-HRMS/MS data combined with chemometric methods and dereplication tools to discover antifungal compounds. We analyze twenty ethanolic plant extracts from Vanda and Cattleya (Orchidaceae) genera. Molecular networking and chemometric methods were used to discriminate ions that differentiate healthy and fungal-infected plant samples. Fifty-three metabolites were rapidly annotated through spectral library matching and in silico fragmentation tools. The metabolomic profiling showed a large production of polyphenols, including flavonoids, phenolic acids, chromones, stilbenoids, and tannins, which varied in relative abundance across species. Considering the presence and abundance of metabolites in both groups of samples, we can infer that these constituents are associated with biochemical responses to microbial attacks. In addition, we evaluated the metabolic dynamic through the synthesis of stilbenoids in fungal-infected plants. The tricin derivative flavonoid- and the loliolide terpenoidfound only in healthy plant samples, are promising antifungal metabolites. LC-HRMS/MS, combined with state-of-the-art tools, proved to be a rapid and reliable technique for fingerprinting medicinal plants and discovering new hits and leads.

Decrease of Greenhouse Gases during an In Vitro Ruminal Digestibility Test of Forage (Festuca arundinacea) Conditioned with Selenium Nanoparticles.

The Festuca arundinacea Schreb. is one of the most used forage grasses due to its duration, productivity, great ecological breadth, and adaptability. Livestock has been criticized for its large production of greenhouse gases (GHG) due to forage. The advancement of science has led to an increase in the number of studies based on nanotechnologies; NPs supplementation in animal nutrition has found positive results in the fermentation of organic matter and the production of fatty acids and ruminal microorganisms. The objectives of this study were (1) to evaluate the in vitro digestibility of forage containing selenium (Se) nanoparticles (NPs), and to identify the specific behavior of the ruminal fermentation parameters of F. arundinacea Schreb. and (2) quantify the production of greenhouse gases (total gas and methane) (3) as well as the release of bioactive compounds (phenols, flavonoids, tannins, and selenium) after fermentation. Three treatments of SeNPs were established (0, 1.5, 3.0, and 4.5 ppm). The effects of foliar fertilization with SeNPs son digestion parameters were registered, such as the in vitro digestion of dry matter (IVDM); total gas production (Atotal gas) and methane production (ACH4); pH; incubation time(to); the substrate digestion rate (S); tSmax and the lag phase (L); as well as the production of volatile fatty acids (VFA), total phenols, total flavonoids, and tannins in ruminal fluid. The best results were obtained in the treatment with the foliar application of 4.5 ppm of SeNPs; IVDMD (60.46, 59.2, and 59.42%), lower total gas production (148.37, 135.22, and 141.93 mL g DM-1), and CH4 (53.42, 52.65, and 53.73 mL g DM-1), as well as a higher concentration of total VFA (31.01, 31.26, and 31.24 mmol L-1). The best results were obtained in the treatment with the foliar application of 4.5 ppm of SeNPs in the three different harvests; concerning IVDMD (60.46, 59.2, and 59.42%), lower total gas production (148.37, 135.22, and 141.93 mL g DM-1), and CH4 (53.42, 52.65, and 53.73 mL g DM-1), as well as a higher concentration of total VFA (31.01, 31.26, and 31.24 mmol L-1). The F. arundinacea Schreb. plants fertilized with 4.5 ppm released-in the ruminal fluid during in vitro fermentation-the following contents: total phenols (98.77, 99.31, and 99.08 mgEAG/100 mL), flavonoids (34.96, 35.44, and 34.96 mgQE/100 g DM), tannins (27.22, 27.35, and 27.99 mgEC/100g mL), and selenium (0.0811, 0.0814, and 0.0812 ppm).

Life cycle assessment of a novel tannin-boron association for wood protection

In these studies of fix boron compounds, associations between tannins and boron (TB) in the form of boric acid appear to be of interest. These TB associations allow the use of boron at very low levels (in compliance with EU restrictions, 2008/58/EC) and limit boron leaching which maintains biological resistance and fire retardant properties. As a consequence, TB wooden products present an extended service life compared to boron compounds alone and were designed to be environmentally-friendly wood protection systems. A follow-up of tannin‑boron use identified the environmental impacts using a life cycle assessment (LCA). This LCA was performed on tannin‑boron preservative products as well as several industrial preservative-treated timbers and concrete used in the landscape. Cr-containing inorganic salt and an alkaline copper quaternary preservative formulation, as well as concrete, have been used as referential materials to compare the environmental footprint with the tannin‑boron treated system. A model was created with life cycle stages used to calculate inputs and outputs during raw material extraction, supplier transportation, manufacturing process, distribution, disposal transportation and processing. Tannin production data were based on Vieira et al. in the field of condensed tannin extraction. However, the extracted tannin in the extraction yield, the inorganic salt, and the process applied are not perfectly comparable with the extraction conditions industrially applied for the Mimosa (Acacia mearnsii) extract which is the major constituent of the TB formulations. The latter is counter-current water extracted without any chemicals or with a limited amount of NaHSO3 or Na2SO3 (at 0.5 % to 1 %) — at a temperature of 70–90 °C. Unfortunately these parameters cannot be elaborated by the LCA program because there is no data available for the production of Na bisulphite or Na bicarbonate in the LCI data used. Other input data were sourced from the ecoinvent v3.8 database. The ReCiPe midpoint method was used to assess the environmental footprint and the CED method was chosen to analyze a general view of the energy-related environmental impacts in the life cycle. Overall, the results demonstrated that tannin‑boron preservatives can be regarded as a low-environmental impact formulation. Additionally, an economic analysis of the development of a commercially-viable tannin‑boron preservative would now be timely.

Chestnut Wood Mud as a Source of Ellagic Acid for Dermo-Cosmetic Applications.

Ellagic acid (EA) has long been recognized as a very active antioxidant, anti-inflammatory, and antimicrobial agent. However, its low bioavailability has often hampered its applications in health-related fields. Here, we report a phospholipid vesicle-based controlled release system for EA, involving the exploitation of chestnut wood mud (CWM), an industrial by-product from chestnut tannin production, as a largely available and low-cost source of this compound. Two kinds of CWM with different particle size distributions, indicated as CWM-A and CWM-B (<100 and 32 µm, respectively), containing 5 ± 1% w/w EA, were incorporated into transfersomes. The latter were small in size (~100 nm), homogeneously dispersed, and negatively charged. 2,2-Diphenyl-1-picrylhydrazyl (DPPH) and ferric reducing/antioxidant power (FRAP) assays indicated up to three-fold improvement in the antioxidant properties of CWM upon incorporation into transfersomes. The kinetics of EA released under simulated physiological conditions were evaluated by UV-Vis spectroscopy and HPLC analysis. The best results were obtained with CWM-B (100% of EA gradually released after 37 days at pH 7.4). A stepwise increase in the antioxidant properties of the released material was also observed. Cell-based experiments confirmed the efficacy of CWM-B transfersomes as antioxidant agents in contrasting photodamage.

The application of coir dust modulates the production of phytochemicals in mycorrhizal Passiflora alata Curtis

The application of efficient organic substrates and arbuscular mycorrhizal fungi (AMF) is a promising alternative to composing low-cost protocols to enhance the biosynthesis of phenolic and terpenes compounds. These biomolecules from Passiflora alata Curtis extracts have anxiolytic effects relevant to the herbal medicine sector. Therefore, the research aimed to establish an efficient agrobiotechnological protocol applying Acaulospora longula Spain & N.C. Schenck and coir dust to increase the production of foliar bioactive compounds in P. alata. For this purpose, plants were grown for 98 days in a greenhouse, inoculated or not with A. longula, and kept in soil supplied or not with 10% of coir dust. Using these plants, the content of foliar primary and secondary metabolites and mycorrhizal parameters were evaluated. The data were submitted to variance analyses and the means were compared by Tukey's test. We used a clustering algorithm to analyse the similarities. The combined use of coir dust and A. longula added to the substrate favoured the production of total saponins and total tannins, in comparison to non-inoculated passion fruits. Moreover, the use of mycorrhizal biotechnology dismissed the application of coir dust to improve the biosynthesis of total phenols and proanthocyanidins. However, these were not alternatives to enhance the concentration of total flavonoids. The combination of A. longula and coir dust in the cultivation substrate of P. alata provides a high biosynthesis of foliar tannins and saponins, which is enhanced over 70%, being important to the herbal medicine industry of anxiolytics.

Changing use of species and hybrids in South African forest plantations

South Africa has 1.2 million hectares of plantations developed progressively through the 20th century. These occur from 23° to 34°S, from near sea level to 2 000 m above sea level and in both Mediterranean winter rainfall and summer subtropical rainfall climates. Plantations supply pulp mills, sawmills, treated pole and mining timber production, and wattle tannin production. The diversity of sites and markets requires planting of a range of taxa of pine, eucalypt and wattle. A survey of planted area by taxa in South African forest plantations is reported and compared to statistics available from national annual reporting on the commercial timber resources in the country. The survey found a similar number of taxa are currently planted (15) as in the 1950s but only 6 of the earlier options remain in use. Changes have occurred in the last 30 years, with 40% of planted area in 2019 using options not available before 1990. From the 1990s, Eucalyptus grandis has been extensively replaced by eucalypt hybrids and E. dunnii and Pinus elliottii × P. caribaea var. hondurensis has become an important pine planting option. Over the past decade, E. nitens replacement with other existing frost tolerant eucalypt planting options has occurred, use of P. radiata has reduced and P. patula has been replaced on a significant scale with P. patula hybrids. Many of these changes have been to mitigate the impact of new pests and pathogens and, on lower productivity sites, periodic severe droughts. However, the new planting options also provide increased yields and have wood properties acceptable to the intended markets. Meeting all three criteria is likely to remain a requirement for successful introduction of future new planting options. The survey indicates a need to revise current national reporting requirements to better reflect use of species and hybrids in South African plantations.