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Proanthocyanin (PA) dimers isolated from Acacia mearnsii bark were enzymatically acylated with palmitic acid as the acyl donor by immobilized Candida antarctica lipase on acrylic resin (Novozym 435). The acylation reaction conditions were optimized by comparing the amount of enzyme, the temperature, the reaction solvents, initial water content, substrate molar ratios and reaction time. The highest acylation conversion of 96.53% was achieved under the follow conditions: PA dimers/palmitic acid at a molar ratio of 1: 10 in tert-amyl alcohol; initial water content of 5% at 60 ℃ for 12 h with 30 g/L enzyme dosage. Introducing palmitic acid into PA dimers significantly improved both the lipophilicity and antioxidant properties. The 1-octanol/water partition coefficient of the PA dimers and their derivatives showed that the lipophilicity of the derivatives were 2.4 times higher than that of the PA dimers. The derivatives exhibited strong antioxidant scavenging capacities, approximately 1.6 times greater than the original dimers. This work is of great significance to expand the application of natural PA dimers in cosmetic and food industries and also lay a foundation for the high value-added utilization of A. mearnsii.

Invasive plants can impact nutrient cycling, potentially creating positive feedbacks for further invasion. We studied the impact of three woody nitrogen (N)-fixing invasive plant species on soil N-cycling and phosphatase activity in a montane tropical forest-grassland mosaic in the Nilgiri Biosphere Reserve in southern India, an ecosystem with > 100-year history of biological invasions. Soils were collected over a year from patches invaded by Acacia mearnsii, Cytisus scoparius, and Ulex europaeus, and from uninvaded grasslands, to assess inorganic N-availability and N-mineralization rates (using in situ open-top mineralization tubes). Phosphatase activity was measured from soils collected at the beginning of the growing season. Soils of invaded areas had higher inorganic N-availability and phosphatase activity than soils of uninvaded areas. Whilst net N-mineralization rates were unchanged between invaded and uninvaded sites, net nitrification rates were higher and net ammonification rates lower in invaded areas, particularly in the dry season. Impacts of C. scoparius and U. europaeus on these variables were similar to each other, and lower than the impacts of A. mearnsii. These results show that invasive N-fixers are significantly altering nutrient availability and cycling, and also changing the proportion of the forms of inorganic N available, in the Nilgiri grasslands. Restoration activities in these invaded grasslands should explore soil N management strategies such as soil C amendments and planting of specific native species, in conjunction with other strategies, to control invasive plants.

Genetic variation in frost tolerance, resistance to the rust fungus Uromycladium acaciae, growth, stem form, and gummosis were evaluated in 110 open-pollinated families of black wattle (Acacia mearnsii De Wild). Families were tested at six frost-prone sites in northern KwaZulu-Natal and southeastern Mpumalanga, South Africa. Frost-hardy provenances were susceptible to rust disease and had poor growth. Locally grown F1 seed sources that originated from cold-hardy Australian seed sources had better growth and were tolerant to rust, but at a cost of lower frost tolerance. Considerable genetic variation was observed between families within seed sources for frost damage (hfm2 = 0.77), rust incidence (hfm2 = 0.89), and height (hfm2 = 0.80). The corresponding narrow-sense heritabilities (hi2) were 0.30, 0.80, and 0.32. Genotype-by-environment interaction levels were low for most traits. Except for a strong genetic correlation between tree height and diameter (0.90), all the pairs of traits had weak to moderate genetic correlations. Recurrent selection will be successful in improving frost tolerance and rust incidence. However, the current population comprises limited germplasm that is both tolerant to frost and resistant to rust. Thus, we recommend infusing germplasm from known cold-hardy Australian provenances into the current population to increase genetic variation for frost tolerance, rust, and growth.

The potential and real negative and positive effects of invasive alien species (IAS) are increasingly recognised by researchers, land managers and decision-makers. However, most of the research and knowledge stems from understandings developed from rural and natural landscapes, with relatively little derived from studies in urban settings. Small towns in particular pose a novel suite of conditions that make the study and mangment of IAS particularly pressing. Here we examined the distribution of seven woody IAS (Acacia mearnsii, Cestrum laevigatum, Eucalyptus spp., Lantana camara, Melia azedarach, Senna didymobotrya and Solanaum mauritianum) within and between five small towns in the Eastern Cape via means of drive-by road surveys of every street in each town. Across the five towns and seven IAS 4,307 individuals were recorded, with the highest densities found in the two more coastal towns. Almost two-thirds (63%) of the IAS were located in residential properties, 24 % in public spaces and 13 % on road verges, closely mirroring the proportional area of these landuses. Within the residential landuse zone specifically, the townships had between 41 % and 61 % of all the recorded IAS plants per town, followed by the affluent neighbourhoods (22 – 41 %) and lastly, the RDP neighbourhoods (6 – 32 %). Cestrum laevigatum was the most abundant woody IAS across the five towns as a whole (1,783 inviduals). The second-most abundant species was M. azedarach (914 stems) and the least recorded was S. mauritianum (44). Additionally, there were differences in the general distribution of the seven species across residential neighbourhoods, with C. laevigatum (71.2 %), M. azedarach (49.3 %) and S. mauritianum (60.0 %) concentrated in township neighbourhoods, whilst A. mearnsii (66.4 %), L. camara (64.1 %) and Eucalyptus spp. (48.6 %) were most common in the affluent neighbourhoods. This study confirms that woody IAS are widespread in small towns of the region, but that they are unevenly distributed between towns and landuses within towns, indicating the need for local-scale inventories and management.

Acacia cyclops, Acacia saligna and Acacia mearnsii are characterized as prolific invasive alien plants (IAPs) presenting a substantial ecological and economic burden on South Africa. While conventionally these species are perceived as weeds having little value, this study attempts to demonstrate their respective potential as a phytomedicinal resource in the treatment of type 2 diabetes – thereby incentivizing their eradication. Moreover, this study aimed to assess the antidiabetic and cytotoxic effects of extracts from these three invasive Australian acacias in vitro. The α-glucosidase and ɑ-amylase activities of ethanolic and aqueous extracts derived from aerial tissues of A. cyclops, A. saligna, and A. mearnsii were investigated, followed by a cytotoxicity assessment using Hoechst 33342-Propidium Iodide (PI) dual staining and quantitative fluorescence microscopy on the human colon (Caco-2) cell line. Of the extracts screened, A. saligna ethanolic bark demonstrated the highest inhibitory activity against α-amylase and α-glucosidase with an IC50 of 10.45 ± 3.79 μg/ml and 2.35 ± 0.61 μg/ml followed by leaf extract depicting strong α-glucosidase (IC50 of 3.64 ± 1.59 μg/ml) and moderate α-amylase (IC50 of 17.67 ± 3.84 μg/ml) inhibition. The IC50 values of all extracts were significantly (p ± 28.36 μg/ml) and Epigallocatechin gallate (IC50 of 68.2 ± 8.34 μg/ml). All extracts were found to be nontoxic at test concentrations on Caco-2 cells as confirmed by Hoescht 33342-PI dual staining. Overall, the findings presented in this study provide the first concurrent account of three invasive Acacias in South Africa reporting on their potential as an alternative therapeutic option for the treatment of type 2 diabetes.

Black wattle (Acacia mearnsii) has great economic value as a commercial source of tannins, timber and a source of firewood for local and international markets. It has been suggested that to maximize the genetic gain of A. mearnsii plantations in South Africa, the gene pool that exist within ICFR needs to be broadened via introduction of new genotypes with diverse traits. In this work, 282 A. mearnsii samples sourced from the ICFR breeding program were genotyped using 11 cross-species SSR markers. Our results showed low to moderate genetic differentiation (FST) among the six breeding subpopulations, with positive inbreeding (FIS) values that could be attributed to an historical inbreeding event. Low levels of relatedness could however indicate some mechanism of inbreeding avoidance. The effects from a recent supplementation of genetic material from two native Australian populations were observed through genetic structuring analyses. Analysis of molecular variance (AMOVA) revealed that significant genetic variation was mainly distributed within populations (75%) and among individuals (23%). The results provide significant information on A. mearnsii population genetic diversity and structure, which can be used for conservation of the current subpopulations and future tree improvement programs.

La estimación de la densidad básica de la madera se realiza mediante el método tradicional regido por la Norma Tappi T 258 om-94, o bien, por la norma chilena NCh 176/2, las cuales son métodos destructivos, que demandan extensos tiempos, altos gastos en mano de obra y gran utilización de material. Buscando métodos que permitan reducir esos inconvenientes se testeó la metodología Seis Sigmas, utilizando el método DMAMC (Definir, Medir, Analizar, Mejorar y Controlar), para mejorar este proceso, y estimar este parámetro en tiempos y costos más reducidos. Para esto se probó la espectroscopía NIR (Near Infrarred) calibrada para predecir la densidad de la madera en Acacia mearnsii, utilizando polvo de astillado en estado seco obtenido de tarugos. El uso de esta tecnología fue apoyado con modelos estadísticos de regresión multivariantes de mínimos cuadrados parciales (PLS, Partial Least Squares), y se generó un modelo de calibración y un modelo de validación para el instrumento. El objetivo de este estudio fue mejorar los tiempos del cálculo de densidad básica, parámetro físico importante para la obtención de información de la biomasa, que se emplea como un estimador del material leñoso de una especie y del rendimiento que alcanzará en el pulpaje, así como para determinar la facilidad con la que esta se puede trabajar. Los niveles de predicción del modelo PLS fueron sobre el 80%, por lo que se valida el uso de la espectroscopía NIR como herramienta para predecir la densidad básica. Además, se aprecia un aumento en los indicadores de calidad, el nivel sigma aumentó de 0,18 a 3, el Cp de 0,26 a 1.08, el Cpk de 0,23 a 1 y los defectos por millón disminuyeron en un 99.6%. Además, utilizando la espectroscopía NIR disminuyen los costos en comparación con el método tradicional.

A acacicultura é uma importante fonte de renda para o Rio Grande do Sul, estando entre as três principais culturas de espécies florestais exóticas presentes no Estado. O objetivo do presente trabalho é analisar quali-quantitativamente as espécies de insetos da Ordem Coleoptera associadas a um plantio de A. mearnsii. Para isso, foram instaladas 36 armadilhas etanólicas de interceptação de voo em um plantio de A. mearnsii, onde foram realizadas quatro coletas quinzenais. Após a coleta, os insetos capturados foram acondicionados em recipientes devidamente identificados e levados ao laboratório para triagem. Foram coletados 440 espécimes de coleópteros, distribuídos em 23 famílias, 82 morfoespécies; destas, 41 foram identificadas em nível de espécie e 41 em nível de gênero. Cerambycidae e Scarabaeidae foram as famílias mais abundantes, perfazendo 32,83% e 12,93% do total de espécimes coletados, respectivamente. Euetheola humilis, com 27 espécimes, teve destaque, sendo a espécie mais abundante.

Context Tannins are phenolic compounds derived from secondary plant metabolism that at moderate levels can limit the excessive degradation of the protein in the rumen and provide greater amino acids availability in the small intestine. Aims Two experiments were performed to determine the best level of inclusion of condensed tannins (CT) from Acacia mearnsii extract in the diet of goat kids. An experiment was performed with 32 castrated crossbreed Boer goat kids, with a mean age of 4 months and mean bodyweight (BW) of 19.7 ± 2.05 kg, to measure nutrient intake and performance, and another experiment was developed with 20 Boer goat kids, at 5 months of age and 29.0 ± 2.45 kg BW, in which the digestibility, nitrogen (N) balance, microbial protein synthesis, ingestive behaviour and blood urea N were determined. In both experiments, a completely randomised design was used, including CT levels at 0, 16, 32 and 48 g/kg DM. Results DM; crude protein; ether extract; neutral detergent fibre (NDF); non-fibrous carbohydrates and total digestible nutrients intakes, ether extract digestibility; time spent on ruminating, idling or chewing; number of chews per bolus; eating and ruminating rate of DM and NDF; N intake and retained, blood urea N and loin eye area were not affected (P > 0.05) by the addition of CT from A. mearnsii extract in the goat kid diets. However, the NDF g/kg BW and BW0.75 intakes and N faecal excretion showed a linear increase (P < 0.05). There was a linear increase trend (P < 0.1) in time spent eating, and a linear decrease on N urinary excretion by CT from A. mearnsii extract inclusion. The digestibility of DM, crude protein, NDF, non-fibrous carbohydrates and total digestible nutrients exhibited a linear decrease (P < 0.05) by CT from A. mearnsii extract inclusion. There was a quadratic increase (P < 0.05) in synthesis and microbial efficiency, final BW, average daily gain, total gain, gain:feed ratio, and hot and cold carcass weights and yields. Conclusion The inclusion of CT from A. mearnsii extract up to 17.7 g/kg DM is recommended, as it improves the synthesis and efficiency of microbial production, increasing the gain:feed ratio and performance of goat kids. Implications The use of condensed tannins from A. mearnsii does not affect the nutrient intakes on goat kids’ diet and also improves performance and carcass trait of these animals.

The stock of biomass and nutrients has been the basis of many studies in the forest area, mainly those that evaluate the nutritional sustainability of the system. The objective of the present work was to evaluate the biomass and nutrients for the hybrid Eucalyptus urograndis and Acacia mearnsii in monospecific and mixed-species stands at the age of 9 years. For this, the study was carried out in an experimental area in South of Brazil, with three treatments: 100% E. urograndis; 100% A. mearnsii; 50% E. urograndis + 50% A. mearnsii. The hybrid E. urograndis showed lower stemwood in mixed-species planting (105.8 Mg ha−1) when compared to monospecific planting (145.5 Mg ha−1), however A. mearnsii, which increased stemwood at planting (213.9 Mg ha−1) relating to its pure planting (143.6 Mg ha−1). The nitrogen concentration in the leaves and stembark (25 and 5 g kg−1, respectively) of A. mearnsii was significantly higher than that found in the respective hybrid E. urograndis components (18 and 3 g kg−1 for leaves and stembark, respectively). A. mearnsii had higher accumulation of biomass and nutrient accumulation in the mixed-species plantation when compared to its monoculture, and the inverse was observed for the hybrid E. urograndis, thus showing that mixed-species planting exerted a competition effect on eucalyptus.

Uromycladium acaciae has damaged plantations of Acacia mearnsii in southern Africa since 2013. Uredinia of a species of Uromycladium have been known on A. mearnsii in South Africa since the 1980s. However, the recent damage is associated with telia and spermogonia. Uredinia and telia were previously treated as conspecific with a phylogenetic species concept. However, uredinia did not form after previous artificial inoculation experiments with teliospores. Controlled studies identified the optimum conditions for basidiospore infection, but the optimum conditions for sporulation and dispersal have not been identified. To investigate the life cycle and field epidemiology of Uromycladium on A. mearnsii, spores were trapped weekly and development of disease symptoms and plant phenology were monitored monthly at three plantations. Telia and spermogonia developed independently from uredinia, and nucleotide polymorphisms between rDNA of uredinia and telia were fixed based on high throughput sequencing and PCRs. All three weather variables measured had a significant effect on teliospore abundance at two of the three sites. Teliospore abundance was greatest during trapping periods when mean relative humidity was high, mean rainfall was 4–5 mm day-1, and mean temperature was 15–16°C. Teliospore counts peaked at the end of summer, potentially the result of epidemic build-up. Results support the hypothesis that despite sharing a most recent common ancestor, uredinia on A. mearnsii in southern Africa are independent to the life cycle of the telial rust, which likely constitutes a new introduction. Furthermore, teliospores of U. acaciae disperse under wet conditions; and, the wet season between October and March is the optimal period for wattle rust development. This article is protected by copyright. All rights reserved.

Black wattle is planted on 110 000 ha in South Africa, and considered economically important for both private and commercial growers. Black wattle is intensively managed, with protection from abiot...

Globally, grasslands are under threat from woody encroachment by invasive alien plants and this undermines grass production. The study sought to determine the effects of Acacia mearnsii clearing on soil physico-chemical properties and grass production. Soil samples were collected from three A. mearnsii invasion statuses and analysed for representative physico-chemical variables. Using line transects and a disc pasture meter (DPM) approaches, equations were developed to predict annual grass dry matter production in areas cleared of A. mearnsii. A. mearnsii significantly (p < 0.05) altered most of the physico-chemical soil characteristics that affected grass production. Predicted grass dry matter production from sites cleared of A. mearnsii ranged from 284 to 362 g m���2 y���1. These production rates were similar to those from uninvaded landscapes, suggesting that background grass production can still be attained even if there is no active soil management. Autogenic recovery thresholds have not been surpassed despite a long history of landscape invasion in the area. Management of invaded grasslands should be informed by an appreciation of local soil background characteristics. The equations developed for grass dry matter prediction may enable farmers to non-destructively estimate forage availability and fuel loads.

This study aimed at obtaining an extract enriched in phenolic compounds from the aerial parts of black wattle waste (Acacia mearnsii De Wild), characterization of its composition, and investigation of its antioxidant potential and preclinical toxicological profile. First, a phenolic compound enriched extract (PCEE) was obtained by sequential fractionation. Thereafter, the main classes of secondary metabolites present in PCEE were identified and quantified. The antioxidant, cytotoxic, and cytogenotoxic activities were evaluated using in vitro assays. Toxicological effects on locomotor function were assessed using in vivo open field and plus maze models. Cinnamic acid and coumarin were isolated from the PCEE and identified. In addition, high contents of phenolic compounds and flavonoids, responsible for the promising antioxidant activity, were quantified. The extract should a dose-dependent in vitro cytotoxicity in HaCaT cells. In the cytogenotoxicity bioassay, no differences in the mitotic index and micronuclei frequency were observed between PCEE and negative control groups. Also, there were no significant effects of the extract on the motor function. Taken together, these results show that the aerial parts of A. mearnsii can be used for obtaining bioactive compounds with the potential for promoting human and animal health.

The prevailing approach of total clearing to contain the spread of invasive plants (IP) in South Africa is generating enormous lignocellulosic wastes. This study examined the possibility of utilizing these wastes in the production of geopolymer composites for use in outdoor environments. Untreated wood particles from Acacia mearnsii and A. longifolia, as well as sugarcane bagasse residues, were incorporated into a geopolymer matrix developed from a binary precursor system of 75% fly ash and 25% metakaolin. The variables considered included precursor-activator ratio (PA), curing pattern (CP), lignocellulosic material (LM), and alkali concentration (Mcon). The production process was established using a mixed factorial experimental design. PA and CP were considered at 2 levels, while LM and MCon were considered at 3 levels. The density of the boards exceeded 1 g cm−3 and are classified as high-density boards. The boards have comparable sorption properties to the cement-bonded particleboard according to the EN 632-2: 2007 standard. However, only A. longifolia boards produced with 12 M NaOH and PA ratio of 2:1 met the mechanical strength requirements. Thermogravimetric analysis revealed that the boards are thermally stable. These results have shown that South African woody IPs are suitable for geopolymer wood composites, but there is still concern about their durability in the alkaline matrix. Scanning electron microscopy micrographs indicated mineralization of the particles and a partial degradation of hemicellulose was confirmed by Fourier transform infrared spectroscopy. Although the degraded components did not prevent geopolymer setting, there is need to further investigate the extent and means of preventing degradation as this can derail the intended use of the product.

Sixth rotation growth measurements of an Acacia mearnsii fertiliser trial established to test the effect of nitrogen (N), phosphorus (P), potassium (K) and lime application on growth and bark produ...

The use of herbal plants in recent years have increased tremendously owing to their user-friendliness, accessibility, and affordability. In this study, the plant species Combretum molle and Acacia mearnsii were phytochemical screened for the existence of active organic compounds, the content of total phenols, flavonoids and antioxidants using different solvents were investigated. The functional groups existing in the plants extracts were identified using FT-IR. The total phenol contents varied from 53.74 ± 5 – 97.29 ± 3 GAE mg/g and 53.74 ± 7 – 98.58 ± 2 GAE mg/g in the extraction powders for C. molle and A. mearnsii. In C. molle, the content of total flavonoids ranged from 76.90 ± 2 – 114.54 ± 0.18 QE mg/g, while 89.40 ± 3 – 105.45 ± 0.15 QE mg/g was found in A. mearnsii. The radical scavenging activities of the solvent extracts against DPPH and the controls revealed that acetone extract of C. molle displayed 99.64% DPPH inhibition, while A. mearnsii showed a maximum activity of 85.53% at 5 µg/ml. The antimicrobial activity of the two plant species was evaluated using diffusion disk and broth dilution methods. The activity by broth dilution of ethanol, methanol and acetone extracts of C. molle exhibited MIC values (39.06 and 78.13 mg/µL) against P. aeruginosa and E. coli strains respectively, while ethanol and chloroform extracts of A. mearnsii showed (39.06 and 78.13 mg/µL) against P. aeruginosa and E. faecalis respectively. Results from this study showed that the leave extracts constitute healthy supplements with antioxidant and antibacterial potentials that could be useful in traditional medicine for the treatment of numerous infectious ailments.

L'Acacia noir (Acacia mearnsii De Wild) fait dorénavant partie intégrante du paysage de la région d'El Kala. Cinquante ans après son introduction, cette légumineuse australienne occupe plus de 3200 ha et constitue une menace majeure pour la biodiversité locale.Le présent travail a été entrepris, d'une part, afin d'assurer une gestion durable des ressources naturelles de la région et, d'autre part, afin de développer une meilleure compréhension des mécanismes déclencheurs de la propagation de l'espèce invasive.Cette étude a pour but d'évaluer les changements des types d'occupation du sol de 1959 à 2016, mais aussi d'examiner l'apparition, l'évolution et la répartition actuelle des taches d'Acacia mearnsii en deux sites, en utilisant les outils de la télédétection aéroportée et satellitaire.Les résultats obtenus montrent que sur les sites 1 (forêt de Boumalek, 1536 ha) et 2 (forêt de Tonga, 1679 ha), les formations végétales initiales, sans Acacia noir, ont perdu respectivement 708 et 581 ha. La subéraie avec sous-bois a subi une rétraction particulièrement remarquable (196 ha à Boumalek, 350 ha à Tonga). En presque 30 ans (de 1987 à 2016), les superficies de l'eucalyptaie et de la subéraie envahies par l'Acacia noir sont passées respectivement de 62 à 487 ha et de 0,2 à 188 ha à Boumalek, de 30 à 730 ha et de 1,6 à 120 ha à Tonga. Durant la période considérée, de presque 60 ans, les perturbations d'origines naturelle et surtout anthropique, ont constitué des facteurs aggravants de l'envahissement, par ouverture de fenêtres d'invasion et par déclenchement de la levée des semences d'Acacia mearnsii. The Black Wattle (Acacia mearnsii De Wild) is now an integral part of the landscape of the El Kala region. Fifty years after its introduction, this Australian legume occupies more than 3200 ha and represents a major threat to local biodiversity.The present work was undertaken on the one hand, in order to ensure a sustainable management of the natural resources of the region; on the other hand, in order to develop a better understanding of the triggering mechanisms for the spread of the invasive species.The purpose of this study is to assess changes in land cover from 1959 to 2016, but also to examine the appearance, evolution and current distribution of the spots of Acacia mearnsii in two sites, using the tools of the airborne and satellite remote sensing.The results obtained show that on sites 1 (forest of Boumalek, 1536 ha) and 2 (forest of Tonga, 1690 ha), the initial plant formations, without Black Acacia, lost 708 and 581 ha respectively. The cork oak forest with undergrowth has undergone a particularly remarkable retraction (196 ha in Boumalek, 350 ha in Tonga). In almost 30 years (from 1987 to 2016), the area of invaded eucalyptus and cork oak forests increased respectively from 62 ha to 487 ha and from 0.2 to 188 ha in Boumalek, from 30 ha to 730 ha and from 1.6 to 120 ha in Tonga.During the period considered, of almost 60 years, disturbances of natural and especially anthropic origin have been aggravating factors of the invasion, by opening invasion windows and by triggering the emergence of Acacia mearnsii seeds.

Roots act as a biological filter that exclusively allows only a portion of the soil-associated microbial diversity to infect the plant. This microbial diversity includes organisms both beneficial and detrimental to plants. Phytophthora species are among the most important groups of detrimental microbes that cause various soil-borne plant diseases. We used a metabarcoding approach with Phytophthora-specific primers to compare the diversity and richness of Phytophthora species associated with roots of native and non-native trees, using different types of soil inocula collected from native and managed forests. Specifically, we analysed (1) roots of two non-native tree species (Eucalyptus grandis and Acacia mearnsii) and native trees, (2) roots of two non-native tree species from an in vivo plant baiting trial, (3) roots collected from the field versus those from the baiting trial, and (4) roots and soil samples collected from the field. The origin of the soil and the interaction between root and soil significantly influenced Phytophthora species richness. Moreover, species richness and community composition were significantly different between the field root samples and field soil samples with a higher number of Phytophthora species in the soil than in the roots. The results also revealed a substantial and previously undetected diversity of Phytophthora species from South Africa.

Invasive alien plants (IAPs) threaten biodiversity and critical ecosystem services worldwide. There is, therefore, an urgent need to develop intervention measures to control the spread of IAPs. Efforts to control and monitor the spread of IAPs would require their current and detailed distribution over a large geographic area. Recently launched multispectral instrument on-board Sentinel-2 provides free data with good spatiotemporal and spectral resolution, compared to Landsat datasets. The Sentinel-2 dataset, therefore, can be a useful source of the IAPs spatial information required for detection and monitoring purposes. We combined Sentinel-2 data with a radiative transfer model to discriminate IAPs (Acacia mearnsii and Acacia dealbata) from surrounding native tree species in Van Reenen, KwaZulu-Natal, South Africa. The forward mode of combined PROSPECT leaf optical properties model and SAIL canopy bidirectional reflectance model, also referred to as PROSAIL was used to simulate reflectance corresponding to bands of Sentinel-MSI, while the PROSAIL model inversion retrieved leaf area index (LAI) and canopy chlorophyll contents (CCC) of the IAPs and native species. Both reflectance and retrieved properties were used to map the distribution of the species within the study area. Our results showed that A. mearnsii and A. dealbata could be accurately discriminated from the surrounding native trees using integrated PROSAIL Sentinel-2 based model. We found that CCC– and LAI-based (% accuracy = 92.8%, 91.4% for CCC and LAI, respectively) modelling produced a higher classification accuracy than field sampling-based modelling (Accuracy = 90.2% (IAP), 82.2% (NAT) and kappa coefficient = 0.84 (IAP), 0.78 (NAT)). Simulated bands corresponding to Sentinel-2 data, on the other hand, produced species maps comparable to field sampling-based maps. Overall, the integrated PROSAIL Sentinel-2 inversion approach proved suitable for detecting and mapping IAPs over a large area. Due to the high spatiotemporal coverage of Sentinel-2, satellite images, the model developed showed the potential to contribute to the IAPs monitoring systems.

Problems associated with the invasiveness of exotic tree species such as Acacia mearnsii have increased recently causing vast damage in environment and economy worldwide. Sao Hill Forest Plantation...

The aim of this study is to assess the curing behaviour and thermal properties of phenol–formaldehyde (PF) adhesives with different degree of tannin substitution using several thermal analysis techniques. Tannin from Acacia mearnsii bark was copolymerized with PF to form a bonding agent for plywood. The resin mixture was heated at 50 °C prior to adding 40% w/w tannin solution, followed by a continuous stirring for 2 h. The amounts of tannin substitution were 20%, 30% and 40% (w/w of PF solids) and 100% PF were used as control. The study shows that the addition of tannin quickened the gel time of the resin notably, parallel with the increase in viscosity of the resin. The dry shear bond strength of the tannin phenol–formaldehyde (TPF) co-polymer ranged between 1.71 and 2.58 MPa as compared to 3.41 MPa for PF. At higher addition of tannin, the shear bond strength reduced significantly predominantly the 40% tannin substitution. Formulation containing 20% tannin was found comparable to that of neat PF. Thermal test revealed that TPF starts to degrade at a lower temperature than PF resin. All TPF resins started to cure at about 125 °C and peaked at 160 °C compared to PF that began to cure at 145 °. The DMA of the resin showed an increase in the resin stiffness with an addition of tannin. These results imply that even though TPF starts to degrade at lower temperature, the cured TPF is relatively stronger than pure PF.

We developed a two-biome (grasslands and fynbos) system dynamics model simulating invasions of three invasive alien plant species – black wattle (Acacia mearnsii) and two pine species (Pinus patula...

Acacia dealbata and A. mearnsii are two invasive species found in coastal, mountain, and riparian Mediterranean habitats. Seed biology and germination traits are important drivers of the competitive performance of plants and may significantly contribute to biological invasions. The seeds of Acacia s.l. have physical dormancy due to an impermeable epidermal layer. The aim of this study was to assess the germination capacity of scarified and non-scarified seeds of A. dealbata and A. mearnsii from different areas of the Mediterranean Basin. To test the seed imbibition capacity, the increase in mass was evaluated. Non-scarified seeds were tested at 15, 20, and 25 °C in light conditions. Scarified seeds were tested at 5, 10, 15, 20, and 25 °C and 25/10 °C in light and dark conditions. Scarified seeds increased in mass more than non-scarified seeds. Both species showed a higher germination capacity at 25 °C in non-scarified seeds, A. dealbata reached a germination maximum of 55%, while A. mearnsii reached 40%, showing a difference among these populations. Scarified seeds of both species reached germination percentages &gt, 95% at all temperatures except at 5 °C in dark conditions. Scarification was necessary to break dormancy and promote germination. The present study provides new knowledge about the seed ecology and germinative behaviour of the two Acacia species under different pre-treatment, temperature, and photoperiod regimes, contributing to the understanding of their invasive behaviour.

Tannin has gained wider acceptance as a dietary supplement in contemporary animal nutrition investigations because of its potential to reduce enteric methane emission. However, a major drawback to dietary tannin intake is the bitter taste and instability in the gastrointestinal tract (GIT). The utilization of fats as coating materials will ensure appropriate masking of the tannin’s aversive taste and its delivery to the target site. The aims of this study were to encapsulate mimosa tannin with palm oil or sunflower oil, and to assess the microcapsules in terms of encapsulation efficiency, morphology, density, and in vitro release of tannin in media simulating the rumen (pH 5.6), abomasum (pH 2.9) and small intestine (pH 7.4). The microencapsulation of mimosa tannin in palm or sunflower oils was accomplished using a double emulsion technique. The results revealed that encapsulated mimosa tannins in palm oil (EMTP) and sunflower oil (EMTS) had high yields (59% vs. 58%) and encapsulation efficiencies (70% vs. 68%), respectively. Compared to unencapsulated mimosa tannin (UMT), the morphology showed that the encapsulated tannins were smaller in size and spherical in shape. The UMT had (p &lt, 0.01) higher particle density (1.44 g/cm3) compared to 1.22 g/cm3 and 1.21 g/cm3 for the EMTS and EMTP, respectively. The proportion of tannins released by the UMT after 24 h in the rumen (94%), abomasum (92%) and small intestine (96%) simulated buffers, reduced (p &lt, 0.01) to 24%, 21% and 19% for the EMTS and 18%, 20% and 16% for the EMTP in similar media and timeframe. The release kinetics for the encapsulated tannins was slow and steady, thus, best fitted by the Higuchi model while the UMT dissolved quickly, hence, only fitted to a First order model. Sequential tannin release also indicated that the EMTS and EMTP were stable across the GIT. It was concluded that the microencapsulation of mimosa tannin in palm or sunflower oils stabilized tannins release in the GIT simulated buffers with the potential to modify rumen fermentation. Further studies should be conducted on the palm and sunflower oils microcapsules’ lipid stability, fatty acid transfer rate in the GIT and antioxidant properties of the encapsulated tannins.

Invasion by exotic woody species is a major concern in grasslands worldwide. Woody invasions pose a particularly serious threat to forest–grassland mosaics globally, but the factors influencing the success of woody species in these systems, including the role of disturbances such as fire, are not well understood. In this study, we evaluated the role of fire in influencing mortality and regeneration success of three globally widespread woody invasives, Acacia mearnsii (black wattle), Cytisus scoparius (scotch broom) and Ulex europaeus (gorse) in the montane forest–grassland mosaics of the Nilgiri Biosphere Reserve in the Western Ghats biodiversity hotspot, India. Our results indicate that mortality and regeneration responses to fire are species-specific. Fire-induced adult mortality was highest in scotch broom and lowest in gorse, and high, but variable in wattle. Burning greatly increased the abundance of gorse and wattle seedlings, but only marginally increased scotch broom seedling abundance. Fire effects on invasive seedling densities were most pronounced at the edges of invasive patches. Overall, our results indicate that fires are likely to differentially affect invasion patterns of these three species, with fire potentially encouraging invasion by gorse and wattle and discouraging invasion by scotch broom.

Invasion of alien plant species can alter local plant diversity and ecosystem processes closely linked to soil organic carbon (SOC) and nutrient dynamics. Soil ecosystem processes such as microbial respiration and enzyme activity have been poorly explored under alien plant invasion and especially following invasive plant species removal. We studied the impact of Prosopis juliflora and Acacia mearnsii invasion and subsequent removal on local plant community composition and diversity and on soil microbial respiration and enzyme activity in two biodiversity hotspots in Southern India. Removal of Prosopis promoted recolonisation of local vegetation as indicated by a 38% and 28% increase in species richness and ground vegetation cover, respectively, compared to an unremoved site. Prosopis and Acacia removal led to a significant reduction in soil microbial biomass C (MBC), respiration, dehydrogenase and urease activity due to increased microbial respiration and N mineralisation rate. Higher metabolic quotients qCO2 in soil at Prosopis and Acacia removed sites indicate that MBC pools declined at a faster rate than SOC, resulting decreased MBC/SOC ratios compared to their respective removed sites. Natural and undisturbed ecosystems maintain more SOC through increased belowground and aboveground C input in the soil, resulting in a higher MBC content per unit SOC. Our results indicate that the interaction between above- and below-ground communities is a critical factor determining the structure and dynamics of local plant communities, especially in ecosystems affected by plant invasions.

Dans la région d’El Kala (extrême Nord-Est algérien), Acacia mearnsii De Wild. a été introduit lors des reboisements de 1970, en mélange à 20 % avec l'eucalyptus. Or, depuis quelques décennies, il est constaté un développement de taches d’invasion par cette espèce australienne dans cette même contrée du pays. L’utilisation d’outils tels qu’un système d'information géographique (SIG), avec des informations spatiales à jour, est nécessaire pour mieux comprendre l'invasion et identifier les écosystèmes potentiels à haut risque. Ainsi, le présent travail a été orienté vers la cartographie afin de procéder à l’étude de la répartition de l’invasion de cette espèce. Deux approches ont été adoptées, la première faisant appel aux données collectées sur le terrain et la seconde aux techniques de télédétection, en appliquant la méthode de classification supervisée sur une image Landsat 8. Les résultats obtenus par les deux méthodes montrent que la superficie envahie avoisine les 3 200 ha, répartis en quatre sites. La quasi-totalité de la surface envahie est occupée par l’eucalyptaie et la suberaie (respectivement 65,0 % et 17,9 % de la superficie totale). La classification de l’image satellite n’a permis de détecter que les paysages fortement envahis, tandis que la méthode des relevés effectués sur le terrain a permis de cartographier sa répartition totale. Toutefois, la superposition des deux cartes montre qu’elles sont majoritairement identiques (0,90 ≤ R ≤ 1). Pour conclure, l’utilisation des données spatialisées, couplées à des données ponctuelles (relevés de terrain), a permis, d’une part, de réduire les contraintes liées à la résolution de l’image Landsat et, d’autre part, de montrer l’importance des méthodologies basées sur les travaux de terrain.

Black wattle is a forest species of great economic importance in the southern of Brazil. Researches for vegetative propagation methods to constitute clonal forests are effective to increase forest productivity. The goal of this work was to evaluate the action of compounds of root promotion in minicuttings of Acacia mearnsii as an alternative to vegetative propagation to the species. The experiment was conducted in July/2018 (winter season), with one negative control, two concentrations of indole butyric acid – IBA (2000 and 4000 mg L-1) and two concentrations of AzoTotal™ (100% e 50%), an inoculant containing Azospirillum brasilense bacterium. In the IBA treatments, the base of minicuttings remained immersed in hydroalcoholic solution 50% for 10 seconds and for the inoculant treatments during 15 minutes. The experiment took place in a greenhouse and after 45 days they were evaluated: the percentage of rooted minicutting; number of roots per minicutting; length of the three largest roots per minicutting; percentage of minicuttings with calluses; percentage of minicuttings survival; percentage of minicutting with budding and percentage of minicutting that kept the leaflets. There was significant difference between treatments considering rooted minicuttings, number of roots by minicutting, length of the three largest roots by minicutting, and there were not observed differences to the other variables analyzed. The use of IBA was more effective for the vegetative propagation process in this species.

The aims of this investigation were to assess the genetic origin of two black wattle seed orchards at molecular levels and to determine genetic diversity within and among the A. mearnsii provenances planted in Southern Mpumalanga, South Africa using a reference population. The method used for sample collection, DNA extraction, PCR and genetic analysis followed the protocol developed in our laboratories for Acacia mearnsii. The overall mean alleles per locus was 8.8 among all A. mearnsii individuals; the highest number of allele was 14.0 for primer AH3-10 and the least was 3.0. for AH3-1 and AH16. The Potgieterskues provenance revealed the highest genetic diversity (He = 0.59), allelic richness (Ar = 5.78) and total number of private alleles (PA = 15), whereas Mittagong showed the lowest He = 0.50 and Ar = 4.42. An unweighted pair group method with Neighbour-joining cluster analysis and Bayesian STRUCTURE analysis, based on allele profiles of 11 microsatellite loci, separated the 281 individual trees into three distinct genetic clusters. The clustering of the samples did not strictly follow the geographic origin of individuals. Both the AMOVA and STRUCTURE analysis revealed the distinctiveness of the Potgieterskues stands with 36% of the trees related to Sheepmoor, Mittagong and Lake George provenances. The Sheepmoor, Mittagong and Lake George provenance largely grouped into the same genetic cluster with no significant genetic differentiation. The relatively larger number of unique allele from the Potgieterskues stand suggest that seed unknown to the ICFR was used to establish the orchard. Using assignment score > 95% as criteria, it was possible to trace the genetic origin of some of the trees in the Sheepmoor orchard. This work is the first of its kind for the South African wattle industry. It will provide the foundation for DNA-based molecular support to the breeding programmes.

Resumo Avaliou-se o efeito da retenção de água de substratos para plantas formulados a partir de diferentes proporções de lodo de esgoto (LETE) solarizado, na produção de mudas de acácia-negra (Acacia mearnsii). O experimento foi conduzido em casa de vegetação e no Laboratório de Física do Solo da Embrapa Clima Temperado. O LETE utilizado foi coletado em leitos de secagem de uma Estação de Tratamento de Esgoto aeróbio de Rio Grande - RS. Os tratamentos consistiram de cinco doses de LETE solarizado, combinadas com cinza de casca de arroz e vermiculita em diferentes proporções (20:40:40, 30:35:35, 40:30:30, 50:25:25 e 60:20:20) e dois substratos comerciais (Beifort® S10 B e Mec Plant®). O delineamento experimental foi de blocos casualizados. Foram avaliadas as características físico-hídricas: água facilmente disponível, água tamponante, água remanescente e capacidade de retenção de água. As variáveis de crescimento avaliadas foram: massa fresca da parte aérea e do sistema radicular. O substrato com 20% de LETE solarizado, 40% vermiculita e 40% cinza de casca de arroz apresentou a melhor condição físico-hídrica para o desenvolvimento de mudas de acácia-negra. Abstract This work evaluated the effect of water retention of plant substrates formulated with different proportions of solarized sewage sludge (SS) in the production of black wattle (Acacia mearnsii) seedlings. The study was conducted in a greenhouse and in the Laboratory of Soil Physics at the Lowland Experimental Station of Embrapa Clima Temperado. The SS was collected in drying beds at an aerobic sewage water treatment plant from Rio Grande, Rio Grande do Sul state. The treatments consisted of five doses of SS-solarized combined with rice husk ash and vermiculite in different proportions (20:40:40, 30:35:35, 40:30:30, 50:25:25 and 60:20:20) and two commercial substrates (controls) (Beifort® S10 B and Mec Plant®). The experimental design was randomized blocks. The following physico-hydric atributes were determined easily available water, buffer water, remaining water and water retention capacity. The following variables were evaluated: dry mass of aerial parts and the dry mass of roots. The substrate with 20% of SS-solarized, 40% of vermiculite and 40% of rice husk ash presented the best physico-hydric condition for the development of black wattle seedlings.

The tree Acacia mearnsii is native to south-eastern Australia but has become an aggressive invader in many countries. In South Africa, it is a significant threat to the conservation of biomes. Detecting and mapping its early invasion is critical. The current ground-based methods to map A. mearnsii are accurate but are neither economical nor practical. Remote sensing (RS) provides accurate and repeatable spatial information on tree species. The potential of RS technology to map A. mearnsii distributions remains poorly understood, mainly due to a lack of knowledge on the spectral properties of A. mearnsii relative to co-occurring native plants. We investigated the spectral uniqueness of A. mearnsii compared to co-occurring native plant species within the South African landscape. We explored full-range (400–2500 nm), leaf and canopy hyperspectral reflectance of the species. The spectral reflectance was collected biweekly from December 23, 2016 and May 31, 2017. We conducted a time series analysis, to assess the effect of seasonality on species discrimination. For comparison, two classification models were employed: parametric interval extended canonical variate discriminant (iECVA-DA) and nonparametric random forest discriminant classifiers (RF-DA). The results of this paper suggest that phenology plays a crucial role in discriminating between A. mearnsii and sampled species. The RF classifier discriminated A. mearnsii with slightly higher accuracies (from 92% to 100%) when compared with the iECVA-DA (from 85% to 93%). The study showed the potential of RS to discriminate between A. mearnsii and co-occurring plant species.

Acacia mearnsii is a commercial forestry tree in South Africa, largely grown from open-pollinated seeds. Clonal deployment of superior selections of the species is restricted due to its poor rootin...

Acacia mearnsii is a tree species commercially cultivated in Africa and South America. This species requires physical or chemical treatments to overcome physical seed dormancy. In this report, we a...

Understanding the drivers of biological invasions in landscapes is a major goal in invasion ecology. The control of biological invasions has increasingly become critical in the past few decades because invasive species are thought to be a major threat to endemism. In this study, by examining the key variables that influence Acacia mearnsii, we sought to understand its potential invasion in eastern Zimbabwe. We used the maximum entropy (MaxEnt) method against a set of environmental variables to predict the potential invasion front of A. mearnsii. Our study showed that the predictor variables, i.e., aspect, elevation, distance from streams, soil type and distance from the nearest A. mearnsii plantation adequately explained (training AUC = 0.96 and test AUC = 0.93) variability in the spatial distribution of invading A. mearnsii. The front of invasion by A. mearnsii seemed also to occur next to existing A. mearnsii plantations. Results from our study could be useful in identifying priority areas that could be targeted for controlling the spread of A. mearnsii in Zimbabwe and other areas under threat from A. mearnsii invasion. We recommend that the plantation owners pay for the control of A. mearnsii invasion about their plantations.

Insect predator densities and plant nutritional status can affect insect herbivore densities, but these effects have not yet been assessed in the context of an invasive species management. This study investigated the influence of (i) altered predatory arthropod abundance and community composition (top-down-effects); and (ii) altered leaf nitrogen and phosphorus levels (bottom-up-effects) as possible causes of fluctuations in herbivore abundance and herbivory on the native tree Brabejum stellatifolium in riparian sites that differ in invasion status (near pristine, heavily invaded by Acacia mearnsii, and restored). Species richness, abundance and composition of herbivorous and predatory arthropods were compared between categories. Herbivore and predator abundance, species richness and assemblage composition were significantly influenced by invasion status. As expected, herbivore abundance was significantly and positively correlated to levels of leaf damage. Leaf nitrogen levels were the highest at restored sites where herbivorous arthropods were also most abundant and the abundance of predators was intermediate. These results suggest that altered leaf nitrogen content is likely a key influence for the increased herbivore pressure on B. stellatifolium at sites under pressure from invasive A. mearnsii and its status. Bottom-up influences therefore may be more important than top-down effects on controlling herbivore abundances in these altered riparian environments.

A new Phytophthora species was found associated with gummosis in black wattle plantations in the subtropical, humid, south of Brazil. The new species Phytophthora acaciae is formally named herein based on phylogenetic and morphological analyses. This is the fourth Phytophthora species found from this pathogen complex in black wattle plantations causing gummosis in Brazil. The other three species are P. nicotianae, P. boehmeriae, and P. frigida. Phytophthora acaciae is heterothallic with amphigynous antheridia, noncaducous, papillate sporangia and is placed in the Phytophthora clade 2 based on nuc rDNA internal transcribed spacer (ITS1-5.8S-ITS2 = ITS) sequences. Maximum parsimony and maximum likelihood phylogenetic analyses of P. acaciae isolates based on multigene sequences, including partial DNA sequences of three nuclear protein-coding genes (β-tubulin, translation elongation factor-1α, and ras-related protein), two mitochondrial protein-coding genes (cytochrome c oxidase subunits I and II), in addition to ITS sequence data, support the delimitation of this new species on Acacia mearnsii from the other previously described clade 2 Phytophthora species. Pathogenicity trial confirmed that the new species causes necrotic lesions on the plant stem, with either the presence or absence of gum.

The objective of this study is to evaluate the fit of Artificial Neural Networks (ANN) for height estimation and evaluation of the effects of consortium in a mixed-species plantation of Eucalyptus globulus (E) and Acacia mearnsii (A). The experiment was installed in 2005, on two farms in the municipality of Piratini - RS, where was planted the species Eucalyptus globulus (E) and Acacia mearnsii (A), in monoculture and mixed in simple lines (50%E:50%A - SL), and double lines (50%E:50%A - DL). The training and evaluation of the networks were made in R-project with the package neuralnet. All ANNs, from the simplest to the most complex, showed high values for Rŷy and low for Syx, BIAS and RMSE, with superior results in ANN 3, 4, and 6, which demonstrates that the information of DBHmin, DBHmean, and DBHmax were important stand attributes. Furthermore, the ANNs were able to capture the different growth patterns shown by the species in the different forms of consortiums, therefore is indicated for the height estimation in monocultures and mixed plantations of Eucalyptus globulus and Acacia mearnsii, and only one ANN would be necessary to represent the entire population.

The development of a sustainable wood energy chain is an essential part of ecological and energy transition in Reunion Island (Indian Ocean), where Acacia mearnsii is the main potential wood energy resource identified to date. In order to assess future wood biomass supply chain strategies, a major first issue is to gain knowledge of the spatial distribution of this species forest stands.In this study, we assessed the potential of very high spatial resolution multispectral imagery for mapping the main forest stands in a study area located the Western Highlands region, where Acacia mearnsii expands alongside Acacia heterophylla, an endemic forest species and Cryptomeria japonica, an exotic forest stand. A reference database including 150 samples of seven classes (Acacia mearnsii (mature and non-mature), Acacia heterophylla (mature and non-mature), Cryptomeria japonica, ‘herbaceous areas’, and ‘bare soils’) was used to classify a Pleiades image acquired in May 2020. Spectral and textural indices were used in an incremental classification procedure using a random classifier.The best results (Kappa = 0.84, global accuracy = 84%) were obtained for the classification using all spectral and textural bands. The resulting map enables analyzing the spatial distribution of the different forest stands.

Abstract In the present study, the tannins from stem and root barks of Tessmannia burttii Harms (Caesalpiniaceae), a plant species abundantly growing in Tanzania and other parts of Africa, were investigated for their suitability in hides tanning. Tannin powder was extracted at selected temperatures (30, 50 and 80 °C) and the influence of each temperature on the crosslinking capacity was evaluated. The interaction mechanism between hide powder collagen and the tannins was studied by Differential Scanning Calorimetry (DSC), trinitrobenzensulfonic (TNBS) acid assay and amino acid hydrolysis methods. Extraction temperatures showed low influence on crosslinking capacity of the tannins. However, extract obtained at 50 °C exhibited best performance in terms of gap size between Tonset and Tpeak. The stem bark extract yield was higher than that from the root bark, but both were within the recommended ranges. The tannin content (61%) of T. burttii stem bark extract was above recommended value (10%), whereas its total phenolic content and total flavonoic content were found to be above that of commercial Acacia mearnsii tannin. The study of cross-linking parameters as a function of pH showed cross-linking to occur via a covalent mechanism at the basic amino groups. However, the bonds were not resistant to acid hydrolysis. The observed interaction mechanism indicated that tannins from stem and root barks of T. burttii belong to the condensed tannin, similar to A. mearnsii (black wattle), a commercial tannin source that was used in this study as a reference. Findings from this study depict that T. burttii extracts are auspicious eco-friendly alternative source of vegetable tannins to overcome the use of chromium salts in the leather industry. Graphical abstract

The acacia bark extract derived from Acacia mearnsii De Wild is rich in proanthocyanidins, whose constituent units are robinetinidol, fisetinidol, catechin, and gallocatechin. In this study, we examined the effect of proanthocyanidins on obesity and diabetes using KKAy mice, a type 2 diabetes model. KKAy mice were fed either a low-fat diet, a high-fat diet, or a high-fat diet mixed with an acacia bark extract, a proanthocyanidins fraction, and other fraction for 7 weeks. Monitoring the changes in the body weight revealed that acacia bark extract and proanthocyanidins fraction could prevent excessive weight gain resulting from a high-fat diet. In addition, increases in the fasting blood glucose level due to high-fat diet intake were found to be suppressed by acacia bark extract and proanthocyanidins fraction. Furthermore, proanthocyanidins derived from acacia bark were found to increase the expression of adiponectin in white adipose tissue, which enhances the action of insulin. In addition, acacia bark-derived proanthocyanidins suppressed gluconeogenesis and fatty acid synthesis in the liver, as well as suppressing the decrease in energy production under pathological conditions in skeletal muscle. In addition, acacia bark-derived proanthocyanidins showed AMPK activation and DPP-4 inhibitory action. Therefore, it was suggested that acacia bark-derived proanthocyanidins lowered fasting blood glucose levels through the above mechanism. These results suggest that proanthocyanidins derived from acacia bark are the active ingredients of the anti-obesity and anti-diabetic effects of acacia bark extract.

Made available in DSpace on 2021-06-25T12:36:51Z (GMT). No. of bitstreams: 0 Previous issue date: 2021-02-07 Clarification of sugarcane juice is one of the most important steps in the sugar manufacturing process, considering that an efficient clarification may result in highly beneficial effects on the quality and yield of the final product, crystal or refined sugar. Currently, depending on the industrial plant and intended product, the use of calcium hydroxide, phosphoric acid and sulfur dioxide as auxiliary agents for clarification has been consolidated, the latter being questioned for causing adverse health reactions. In this context, the present study evaluated the performance of the natural black Acacia (Acacia mearnsii) tannin extract as an alternative for the sugarcane juice clarification. The results showed that tannin dosages between 300 and 500 ppm along with liming applied at pH 7.3 and 3 ppm of anionic flocculant provided the best performance, resulting in 32-34% of color removal and 89-93% of turbidity removal. Under these conditions, starch and dextran removal increased, 90 and 98%, as compared to 69% and 96%, obtained with conventional treatment. The performance of the tannin also reduced the calcium hardness of clarified juice by up to 18% compared to the conventional treatment, which in turn may prevent fouling in the subsequent steps. Sao Paulo State Univ, Dept Food Engn & Technol, Sao Jose Do Rio Preto, SP, Brazil Sao Paulo State Univ, Dept Food Engn & Technol, Sao Jose Do Rio Preto, SP, Brazil

Invasive alien species (IAS) threaten tropical grasslands and native biodiversity and impact ecosystem service delivery, ecosystem function, and associated human livelihoods. Tropical grasslands have been dramatically and disproportionately lost to invasion by trees. The invasion continues to move rapidly into the remaining fragmented grasslands impacting various native grassland-dependent species and water streamflow in tropical montane habitats. The Shola Sky Islands of the Western Ghats host a mosaic of native grasslands and forests; of which the grasslands have been lost to exotic tree invasion (Acacias, Eucalyptus and Pines) since the 1950s. The invasion intensities, however, differ between these species wherein Acacia mearnsii and Pinus patula are highly invasive in contrast to Eucalyptus globulus. These disparities necessitate distinguishing these species for effective grassland restoration. Further, these invasive alien trees are highly intermixed with native species, thus requiring high discrimination abilities to native species apart from the non-native species.Here we assess the accuracy of various satellite and airborne remote sensing sensors and machine learning classification algorithms to identify the spatial extent of native habitats and invasive trees. Specifically, we test Sentinel-1 SAR and Sentinel-2 multispectral data and assess high spatial and spectral resolution AVIRIS-NG imagery identifying invasive species across this landscape. Sensor combinations thus include hyperspectral, multispectral and radar data and present tradeoffs in associated costs and ease of procurement. Classification methods tested include Support Vector Machine (SVM), Classification and Regression Trees (CART) and Random Forest (RF) algorithms implemented on the Google Earth Engine platform. Results indicate that AVIRIS-NG data in combination with SVM recover the highest classification skill (Overall −98%, Kappa-0.98); while CART and RF yielded < 90% accuracy. Fused Sentinel-1 and Sentinel-2 produce 91% accuracy, while Sentinel-2 alone yielded 91% accuracy with RF and SVM classification; but only with higher coverage of ground control points. AVIRIS-NG imagery was able to accurately (97%) demarcate the Acacia invasion front while Sentinel-1 and Sentinel-2 data failed. Our results suggest that Sentinel-2 images could be useful for detecting the native and non-native forests with more ground truth points, but hyperspectral data (AVIRIS-NG) permits distinguishing, native and non-native tree species and recent invasions with high precision using limited ground truth points. We suspect that large areas will have to be mapped and assessed in the coming years by conservation managers, NGOs to plan restoration, or to assess the success of restoration activities, and several data procurement and analysis steps may have to be simplified.

Due to their natural origin and broad availability, industrial tannin extracts are extending their application field from the classical, and still principal, application in tannery, to oenology, pharmacy, adhesives and material science. Despite the growing interest, not much is known about the thermal valorization of these biomolecules. In this article we present the thermal properties of the eight most common commercial tannin extracts and their elemental chemical composition to shed light on the end-life of the bio-materials based on these polyphenols. Results have shown that hydrolysable tannins can be managed similarly to wood, while condensed tannins have higher heating values but also generally higher chlorine content. Sumac and gambier leaf extracts registered contained heating values and significant amounts of ashes rich in calcium and sulfur. The high chlorine content observed for the extracts of mimosa (Acacia Mearnsii) does not hinder the combustion of its derived products which can still be thermally valorized. Mimosa tannin-based materials can also be added up to 2% to wood pellets and briquettes without significantly affecting the overall quality of the biofuels according to the in-force standards.

Tannins are compounds able to form complexes with proteins limiting their ruminal degradation and thus the synthesis of some odour-active compounds may be inhibited. Tannins are broadly divided in condensed tannins (CT) and hydrolysable tannins (HT). The study aimed to assess the influence of dietary inclusion of three commercial tannin extracts, namely mimosa (Acacia mearnsii; CT), chestnut (Castanea sativa; HT) or tara (Caesalpinia spinosa; HT) on volatile profile and flavour of meat and kidney fat from lambs. Comisana male lambs were divided into four groups (n = 9 each) and fed for 75 days with a concentrate-based diet (CON) or CON supplemented with 4% of one of the tannin extracts. Tannins reduced “pastoral” odour in perirenal fat of lambs the meat of which was characterized by a very low perception of this attribute. It may be assumed that p-cresol and 8-methylnonanoic acid mostly contributed to “pastoral” odour expression in the diet without condensed or hydrolysable tannins.

The objective of this study was to determine the optimum level of condensed tannins (CTs), delivered as Acacia mearnsii extract, for inclusion in the diet of goats for enhancing growth, commercial cuts, the physicochemical composition and fatty acid (FA) profile of the meat and meat sensory attributes. Thirty-two castrated crossbreed Boer goats with a mean age of four months and a mean body weight (BW) of 19.7 ± 2.05 kg were distributed in a completely randomized design. The diets varied in level of CTs [0, 16, 32 and 48 g/kg dry matter (DM)] from an Acacia mearnsii extract. Final BW; acid detergent fiber (ADF); shoulder, neck and rib weight; and loin yield increased quadratically (P ≤ 0.05) with the amount of CTs in the diet. Except for a trend of a quadratic reduction in luminosity color (P = 0.07) and a linear reduction in collagen deposition (P = 0.03) with increasing level of dietary CTs, the meat physicochemical parameters were unaffected by CTs inclusion. With increasing amount of CTs from Acacia mearnsii extract in the diet, the concentrations of C17:1 and C18:1 cis-9 in the longissimus lumborum of goats linearly decreased, whereas those of C18:0, C18:2 cis-9, cis-12 and C18:3 cis-9, cis-12, cis-15 (P ≤ 0.05) linearly increased. In addition, the values of total saturated FA (ΣSFA), polyunsaturated FA (ΣPUFA), ratio of ΣPUFA:ΣSFA and ΣPUFA:monounsaturated FA (ΣMUFA) increased (P ≤ 0.05) with increasing CTs level; in contrast, ΣMUFA and the ΣMUFA/ΣSFA ratio decreased. Other FA sums and ratios were not affected by the inclusion of CTs in the diet. The inclusion of dietary CTs tended to unfavorably reduce the FA index and enzymatic activity of Δ9-desaturase C16 (P ≤ 0.10). However, there was a linear decrease (P ≤ 0.05) in Δ9-desaturase C18 and elongase enzymatic activities and the hypocholesterolemic to hypercholesterolemic FA ratio (h:H) index with increasing level of dietary CTs, and the atherogenicity index (AI) tended to increase as the CTs level increased (P = 0.06). The dietary inclusion of the Acacia mearnsii extract improved the flavor, aroma, softness and overall acceptance of goat kid meat (P ≤ 0.05). Linear response plateau (LRP) analysis demonstrated that Acacia mearnsii levels of 16 and 32 g/kg DM had similar effects and increased growth performance and carcass cut weights (P

With A. mearnsii being one of the most successful invaders globally, its management has become a large part of invasive alien species management programs, especially in South Africa, where a significant investment of about 561.9 million rands has been made to eliminate it. Despite this huge investment, there is still no sign that the spread of this species has diminished. To ensure that the damage caused by A. mearnsii is halted, professionals must understand how it spreads and persists. Accurate data on the spatial distribution of A. mearnsii might help to develop useful and successful management techniques for savannah environments, particularly in protected mountainous grasslands. This study, therefore, developed a GIS model for predicting the potential spatial spread of A. mearnsii in a protected mountainous grassland ecosystem using spatiotemporal data derived from Landsat and Sentinel-2 imageries. The study used environmental factors like slope aspect, elevation, distance from streams, and soil type and rainfall. Other climatic variables like land surface temperature derived from the thermal band of Landsat images were included in the environmental factors. The influence of species interactions with fire severity and animal populations was also included as indicator variables. The species' AUC of 0.83 is estimated, and the model fit is a sign of a successful model. The study showed that the spread of A. mearnsii was influenced primarily by the following factors: The average Land surface temperature, aspect, changes in land surface temperature, and rain from 2000 to the present, and distance to the river. The species increased in areas where there was a reduction in both land surface temperature and rainfall. The predicted circumstances of decreasing temperature and rainfall events may lead to widespread invasion by A. mearnsii while nevertheless changing community structure, composition, hydrological properties, and other essential ecosystem services in the examined region.