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Acacia mearnsii byproducts are naturally endowed with a plethora of diverse polyphenols that exhibit antioxidant properties indicating potential application in enhancing oxidative shelf-life of perishable foods. The current study evaluated the oxidative shelf-life of raw ground beef patties fortified with 450 μg/g of polyphenolic extracts from A. mearnsii bark (AMBE) or leaves (AMLE) compared to positive (sodium metabisulphite; SMB) and negative (no extract; CTL) controls for 9 d at 4 °C in a simulated retail display. The AMBE had higher (P ≤ 0.05) contents of proanthocyanidins, and total phenols, flavonoids and tannins, and consequently demonstrated greater (P ≤ 0.05) in vitro antioxidant activity than AMLE. The polyphenolic extracts increased (P ≤ 0.05) antioxidant activity in beef patties compared to the CTL though they were outperformed (P ≤ 0.05) by the SMB. Fortification of beef patties with the polyphenolic extracts, particularly AMBE, delayed colour deterioration and oxidation of myoglobin during retail display relative to the CTL but were less efficient than SMB (P ≤ 0.05). Beef patties fortified with the polyphenolic extracts and SMB had comparable (P > 0.05) peroxide values, TBARS and p-Anisidine values which were all lower (P ≤ 0.05) than those for the CTL patties. The order of protein thiol content in beef patties was as follows: CTL ≥ AMLE ≥ AMBE ≥ SMB (P ≤ 0.05). Findings suggest that A. mearnsii-derived polyphenolic antioxidants, particularly AMBE has great potential to extend oxidative shelf-life of raw beef patties., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper. All authors declare that there are no actual or potential conflicts of interest including financial, personal, or other relationships with other people or organizations that could inappropriately influence, or be perceived to influence, this work., (Copyright © 2024 The Author(s). Published by Elsevier Ltd.. All rights reserved.)

A widely disseminated native species from Australia, Acacia mearnsii , which is mainly cultivated in Brazil and South Africa, represents a rich source of natural tannins used in the tanning process. Many flowers of the Acacia species are used as sources of compounds of interest for the cosmetic industry, such as phenolic compounds. In this study, supercritical fluid extraction was used to obtain non-volatile compounds from A. mearnsii flowers for the first time. The extract showed antimicrobial activity and the presence of p -anisic acid, a substance with industrial and pharmaceutical applications. The fractionation of the extract was performed using a chromatographic column and the fraction containing p -anisic acid presented better minimum inhibitory concentration (MIC) results than the crude extract. Thus, the extraction process was optimized to maximize the p -anisic acid extraction. The response surface methodology and the Box-Behnken design was used to evaluate the pressure, temperature, the cosolvent, and the influence of the particle size on the extraction process. After the optimization process, the p -anisic acid yield was 2.51% w / w and the extraction curve was plotted as a function of time. The simulation of the extraction process was performed using the three models available in the literature., Competing Interests: The authors declare no conflicts of interest.

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 (F ST ) among the six breeding subpopulations, with positive inbreeding (F IS ) 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., (© 2021. The Botanical Society of Japan.)

Background: Recent studies demonstrated that warming and elevated carbon dioxide (CO 2 ) indirectly affect the soil microbial community structure via plant root exudates. However, there is no direct evidence for how the root exudates affect soil microbes and how the compositions of root exudates respond to climate change., Results: The results showed that warming directly decreased biomass of soil-borne bacteria and fungi for Acacia mearnsii De Willd but it did not impact soil microbial community for Eucalyptus urophylla S.T. Blake. In contrast, elevated CO 2 had strong direct effect on increasing soil microbial biomass for both plant species. However, plant roots could significantly increase the secretion of antibacterial chemicals (most probable organic acids), which inhibited the growth of bacteria and fungi in elevated CO 2 environment. This inhibitory effect neutralized the facilitation from increasing CO 2 concentration on microbial growth., Conclusions: We concluded that climate change can directly affect microorganisms, and indirectly affect the soil microbial community structure by changes in composition and content of plant root exudates.

The stability and bioaccessibility of polyphenol from Acacia mearnsii bark were measured at various stages during in vitro simulated digestion. Subsequently, the changes in the total polyphenol content (TPC) and biological activity were studied. The results showed that the phenolic compounds from A. mearnsii remained stable, and TPC underwent few changes during gastric digestion. Nonetheless, intestinal digestion led to the degradation of proanthocyanidins (PAs) and a significant decrease in TPC (26%). Degradation was determined by normal-phase HPLC and gel permeation chromatography. Only monomers, dimers, and trimers of flavan-3-ols were identified in the serum-accessible fraction for characterization of their bioaccessibility. The results also indicated the obvious antioxidant capacity of PAs from A. mearnsii bark, and ~53% of the α-glucosidase⁻inhibitory effect was preserved. All these findings show that PAs from A. mearnsii bark as a native plant source may be particularly beneficial for human health as a natural nutritional supplement.

The study assessed the effect of Acacia mearnsii tannin extract supplementation grazing dairy cows on dry matter (DM) intake, enteric methane (CH 4 ) emission, and performance. Twelve Holstein cows were divided into two groups and subjected to two treatments that consisted of millet pasture (Pennisetum glaucum L.) plus supplementation with 6 kg of concentrate (750-g/kg ground corn and 250-g/kg soybean meal) including or excluding 120-g tannin extract. The trial design was a double reversal using three periods of 28 days each, with 21 days for the adaption period, and 7 days for sample collection. Herbage intake was measured using the n-alkane technique, and daily CH 4 emission was measured with the sulfur hexafluoride tracer gas technique. Individual total DM intake (mean = 17.1 kg/day), herbage DM intake (mean = 11.8 kg/day), and milk production (mean = 19.2 kg/day) were similar between treatments. CH 4 emission significantly decreased (32%, P < 0.05) in the animals supplemented with tannin extract, compared to non-supplemented animals. On the other hand, as proportion of DM intake or milk production, methane emission tended to decrease in tannin-supplemented animals. Supplementing dairy cows grazing a millet pasture with 120-g tannin extract reduced daily CH 4 emission without affecting animal performance.

The present study was designed to characterize the polyphenols isolated from Acacia mearnsii bark crude extract (B) and fractions (B1-B7) obtained by high-speed counter-current chromatography (HSCCC) and evaluate their anti-inflammatory and carbolytic enzymes (α-glucosidase and α-amylase) inhibitory activities. Fractions B4, B5, B6, B7 (total phenolics 850.3, 983.0, 843.9, and 572.5 mg·g -1 , respectively; proanthocyanidins 75.7, 90.5, 95.0, and 44.8 mg·g -1 , respectively) showed significant activities against reactive oxygen species (ROS), nitric oxide (NO) production, and expression of pro-inflammatory genes interleukin-1β (IL-1β) and inducible nitric oxide synthase (iNOS) in a lipopolysaccharide (LPS)-stimulated mouse macrophage cell line RAW 264.7. All the extracts suppressed α-glucosidase and α-amylase activities, two primary enzymes responsible for carbohydrate digestion. A. mearnsii bark samples possessed significantly stronger inhibitory effects against α-glucosidase enzyme (IC 50 of 0.4-1.4 μg·mL -1 ) than the pharmaceutical acarbose (IC 50 141.8 μg·mL -1 ). B6 and B7 (IC 50 17.6 and 11.7 μg·mL -1 , respectively) exhibited α-amylase inhibitory activity as efficacious as acarbose (IC 50 15.4 μg·mL -1 ). Moreover, B extract, at 25 µg·mL -1 , significantly decreased the non-mitochondrial oxidative burst that is often associated with inflammatory response in human monocytic macrophages., (Copyright © 2017 China Pharmaceutical University. Published by Elsevier B.V. All rights reserved.)

Tannins from Acacia mearnsii were encapsulated using four different sol-gel methods acid (SGAR), basic (SGBR), silicate (SGSR) and non-hydrolytic (SGNHR) routes. The hybrid materials were analyzed using a set of techniques to characterize their structure, texture and morphology. The antimicrobial performance of the encapsulated materials was evaluated against different microorganisms (Staphylococcus aureus, Escherichia coli, Aspergillus niger and Candida sp.). The data showed that the encapsulation route significantly affects the characteristics of the resulting hybrid materials. Better functional performances were obtained using the silicate route, which produced mesoporous materials with a small surface area (0.96m 2 g -1 ) and small particle size (<1nm). These characteristics promoted the gradual release of tannins in an aqueous medium and improved their interactions with microorganisms. Furthermore, the process demonstrated the preservation of tannins after synthesis and increased antimicrobial activity (via a controlled tannin release), as demonstrated by the moderate activity against filamentous fungi and yeast., (Copyright © 2016. Published by Elsevier B.V.)

The volatile oils of the leaves and the stem bark of Acacia mearnsii de Wild obtained by hydro-distillation were analysed by gas chromatography-mass spectrometry. A total of 20, 38, 29 and 38 components accounted for 93.8%, 92.1%, 78.5% and 90.9% of the total oils of the fresh, dry leaves and fresh, dry stem bark, respectively. The major components of the oil were octadecyl alcohol (25.5%) and phytol (10.5%); cis-verbenol (29.5%); phytol (10.1%) and phytol (23.4%) for the fresh leaves, dried leaves, fresh stem, dry stem bark, respectively. Oral administration of essential oils at a dose of 2% showed significant (p < 0.05) anti-inflammatory properties in the albumin-induced test model in rats. Oils from the fresh leaves and dry stems inhibited inflammation beyond 4 h post treatment. The potent anti-inflammatory activity of essential oils of A. mearnsii hereby confirmed its traditional use in treating various inflammatory diseases.

(13)C NMR is an effective method of characterizing proanthocyanidin (PAC) tannins in quebracho (Schinopsis lorentzii) heartwood and black wattle (Acacia mearnsii) bark, before and after commercial extraction. The B-rings of the constituent flavan-3-ols, catechols (quebracho) or pyrogallols (wattle), are recognized in unprocessed source materials by "marker" signals at ca. 118 or 105ppm, respectively. NMR allows the minimum extraction efficiency to be calculated; ca. 30%, and ca. 80%, for quebracho heartwood and black wattle bark, respectively. NMR can also identify PAC tannin (predominantly robinetinidin), and compare tannin content, in bark from other acacia species; tannin content decreases in the order A. mearnsii, Acacia pycnantha (87% of A. mearnsii), Acacia dealbata and Acacia decurrens (each 74%) and Acacia karroo (30%). Heartwood from an underexploited PAC tannin source, Searsia lancea, taxonomically close to quebracho, shows abundant profisetinidin and catechin PACs. NMR offers the advantage of being applicable to source materials in their native state, and has potential applications in optimizing extraction processes, identification of tannin sources, and characterization of tannin content in cultivar yield improvement programmes., (Copyright © 2013 Elsevier Ltd. All rights reserved.)

With the emergence of multidrug-resistant organisms, combining medicinal plants with synthetic or orthodox medicines against resistant bacteria becomes necessary. In this study, interactions between methanolic extract of Acacia mearnsii and eight antibiotics were investigated by agar diffusion and checkerboard assays. The minimum inhibitory concentrations (MICs) of all the antibiotics ranged between 0.020 and 500 μg/mL while that of the crude extract varied between 0.156 and 1.25 mg/mL. The agar diffusion assay showed that extract-kanamycin combination had zones of inhibition ≥20 ± 1.0 mm in all the bacteria tested (100%), followed by extract-chloramphenicol (90%) > extract-ciprofloxacin = extract-tetracycline (70%) > extract-amoxicillin (60%) > extract-nalidixic acid (50%) > extract-erythromycin (40%) > extract-metronidazole (20%). The checkerboard showed synergistic interaction (61.25%), additivity/indifference (23.75%) and antagonistic (15%) effects. The synergistic interaction was most expressed by combining the extract with tetracycline, metronidazole, amoxicillin, ciprofloxacin, chloramphenicol and nalidixic acid against E. coli (ATCC 25922), erythromycin, metronidazole, amoxicillin, chloramphenicol and kanamycin against S. aureus (ATCC 6538), erythromycin, tetracycline, amoxicillin, nalidixic acid and chloramphenicol against B. subtilis KZN, erythromycin, metronidazole and amoxicillin against E. faecalis KZN, erythromycin, tetracycline, nalidixic acid and chloramphenicol against K. pneumoniae (ATCC 10031), erythromycin, tetracycline, metronidazole and chloramphenicol against P. vulgaris (ATCC 6830), erythromycin, tetracycline, amoxicillin and chloramphenicol against S. sonnei (ATCC 29930), metronidazole, amoxicillin and chloramphenicol against E. faecalis (ATCC 29212) and ciprofloxacin and chloramphenicol against Proteus vulgaris KZN. The synergistic interactions indicated that the bactericidal potentials of the antibacterial agents were improved and combining natural products with antibiotic could be potential sources for resistance-modifying agents useful against infectious multi-drug resistant bacteria.

Acacia mearnsii De Wild. (Fabaceae) is a medicinal plant used in the treatment of microbial infections in South Africa without scientific validation of its bioactivity and toxicity. The antimicrobial activity of the crude acetone extract was evaluated by both agar diffusion and macrobroth dilution methods while its cytotoxicity effect was assessed with brine shrimp lethality assay. The study showed that both bacterial and fungal isolates were highly inhibited by the crude extract. The MIC values for the gram-positive bacteria (78.1-312.5) μg/mL, gram-negative bacteria (39.1-625) μg/mL and fungal isolates (625-5000) μg/mL differ significantly. The bacteria were more susceptible than the fungal strains tested. The antibiosis determination showed that the extract was more (75%) bactericidal than bacteriostatic (25%) and more fungicidal (66.67%) than fungistatic (33.33%). The cytotoxic activity of the extract was observed between 31.25 μg/mL and 500 μg/mL and the LC(50) value (112.36 μg/mL) indicates that the extract was nontoxic in the brine shrimp lethality assay (LC(50) > 100 μg/mL). These results support the use of A. mearnsii in traditional medicine for treatment of microbial infections. The extract exhibiting significant broad spectrum antimicrobial activity and nontoxic effects has potential to yield active antimicrobial compounds.

Acacia mearnsii, among the 100 worst invasive weeds worldwide, negatively impacts native biodiversity, agriculture, and natural ecosystems. Global climate change, characterized by rising temperatures and altered precipitation patterns, enhances the risk of A. mearnsii invasion in Asia, making it crucial to identify high-risk areas for effective management. This study performed species distribution modeling using the maximum entropy (MaxEnt) algorithm to predict the potential introduction and spread of A. mearnsii under various climate scenarios based on shared socio-economic pathways (SSP2-4.5 and SSP5-8.5). Currently, only 4.35% of Asia is invaded, with a high invasion risk identified in six countries, including Bhutan, Lebanon, and Taiwan, where more than 75% of their areas are threatened. Under future climate scenarios, 21 countries face invasion risk, among which 14 countries, such as Georgia, Laos, Republic of Korea, and Turkey, are at moderate to very high risk, potentially encompassing up to 87.89% of their territories. Conversely, Northern Asian countries exhibit minimal changes in invasion risk and are considered relatively safe from invasion. These findings underscore that climate change will exacerbate invasion risks across Asia, emphasizing the urgent need for robust management strategies, including stringent quarantine measures and control efforts, to mitigate the threat of A. mearnsii expansion. [ABSTRACT FROM AUTHOR]

Concerns on the expanding infestation of several Acacia species in the southern Mediterranean European countries have triggered an ever-growing requirement for costly targeted control actions. Valorizing biomass waste produced could help promote and better finance these actions. For that purpose, wood wastes from invasive control actions were tested regarding their pulp and paper potential, aiming to entice cellulose industries to partake in future conservation actions. Wood waste from the five most pervasive Acacia species was studied (Acacia dealbata Link, Acacia longifolia Willd, Acacia mearnsii De Wild, Acacia melanoxylon R.Br, and Acacia saligna Labill) regarding physical and chemical characteristics, and a central composite design was used to optimize alkali charge and reaction temperature on pulping yield and delignification. Bleached kraft pulps were produced with each species' optimized conditions and for an equitable mixture of all species. Optimized pulp yields (52.6%–53.5%) and pulp polymerization degree (2867–3690) of Acacia species were higher than those of Eucalyptus globulus Labill (used as reference). Optimized bleached pulps were refined and fiber, pulp, and handsheet properties determined. Acacia dealbata and A. longifolia presented high specific wood consumption and lower handsheet strength properties, pointing to overall lower pulping potential, while A. melanoxylon and A. mearnsii characteristics were equal to or higher than those of E. globulus. A. saligna pulp and handsheet characteristics appear more suited for tissue paper. The Acacia mixture achieved acceptable characteristics, enabling the indiscriminate use of Acacia wood regardless of the species. As a shortcoming, the Acacia pulps showed the worst optical characteristics, with brightness dropping substantially with beating (64%–76%) when compared to E. globulus (81%). [ABSTRACT FROM AUTHOR]

Acacia mearnsii, an invasive alien species, is the main resource identified for the energy transition initiated on Reunion Island. It is, therefore, critical to identify the existent forest stands within the island's large tropical forest area and to determine which of these stands are accessible for logging operations. In this study, a very high-spatial-resolution image was used to map forest (Acacia mearnsii, Acacia heterophylla, Cryptomeria japonica) and non-forest land cover. To identify the accessible forest stands, we developed a geographic information system (GIS) processing chain, accounting for barriers, the distribution of slopes, and the location of forest roads. User-defined parameters, such as the slope threshold and maximal distance to forest roads, allow different scenarios to be explored. The classification yields an overall accuracy of 88% and a Kappa index of 0.86 and highlights the areas occupied by the different types of Acacia. By applying the GIS processing chain for a standard scenario, the results show that only 19% of the initial study area of 637 ha of Acacia mearnsii patches is suitable for exploitation. In conclusion, our results demonstrate how remote sensing (RS) and GIS can be combined to provide valuable tools for forest managers to design management plans for invasive alien forest species. [ABSTRACT FROM AUTHOR]

This work aimed to obtain and investigate the properties and composition of extracts from flowers of Acacia mearnsii; this tree is widely cultivated because the bark is used as a raw material for various industry segments, but the flowers are not yet explored. The essential oil was evaluated by GC/FID, GC/MS, and GC/O. The antioxidant activity (DPPH and phosphomolybdenum methods) and chemical composition were investigated for a water-soluble extract, a by-product of the extraction process. 85.8% of the compounds present in the essential oil were identified, 8-heptadecene being the major compound. The main scents detected by the olfactory analysis were roast nutty, coffee, sweet, and floral. The water-soluble extract showed antioxidant activity that may be related to phenolic compounds. Results obtained from the LC-qTOF/MS analysis have shown that 25 likely flavonoids, such as naringenin, myricetin, quercetin, and rutin are present in the extract. [ABSTRACT FROM AUTHOR]

Simple Summary: The anthropogenic generation of greenhouse gases (GHG) from the production of ruminants has contributed to environmental deterioration throughout the world; therefore, reducing their production becomes one of the main objectives today. The manipulation of the ruminant diet with forage sources rich in bioactive compounds (tannins) is considered an alternative to mitigate the production of CH4 and improve the productive performance of the animals. Based on this, this research aimed to evaluate the effect of the incorporation of different amounts of Acacia mearnssi, rich in tannins, on the parameters of ruminal degradation, digestibility of DM and OM, and the generation of gas, CH4, and CO2. The incorporation of A. mearnssi forage in the ration had a reducing effect on GHG production and possibly improved utilization of dietary protein in response to the presence of tannins. However, even with the lowest level of acacia in the diet, the effective digestion of DM and OM was affected. Under the conditions of this study, it was concluded that it is possible to replace traditional forages with up to 20% of A. mearnsii, without observing changes in the production of greenhouse gases with respect to the control treatment (0% of A. mearnsii); however, A. mearnsii is not usable because it significantly decreases rumen degradability of DM and OM, which would considerably affect the production in animals. In recent years, the worrying generation of GHG from ruminant production has generated widespread interest in exploring nutritional strategies focused on reducing these gases, presenting the use of bioactive compounds (tannins) as an alternative in the diet. The aim of this research was to determine the effect of the addition of different levels of Acacia mearnsii on ruminal degradation, nutrient digestibility, and mitigation of greenhouse gas production. A completely randomized design with four treatments and six repetitions was used. The treatments were: T1, T2, T3, and T4 diets with, respectively, 0%, 20%, 40%, and 60% A. mearnsii. The rumen degradation kinetic and in vitro digestibility, and the production of gas, CH4, and CO2 were evaluated. In situ rumen degradation and in vitro digestibility of DM and OM showed differences between treatments, with T1 being higher (p < 0.05) in the degradation of the soluble fraction (A), potential degradation (A + B), and effective degradation for the different passage rates in percent hour (0.02, 0.05, and 0.08), compared to the other treatments. Rumen pH did not show differences (p > 0.05) between treatments. The lowest (p < 0.05) gas, CH4, and CO2 production was observed in treatments T1 and T2 with an approximate mean of 354.5 mL gas/0.500 g fermented DM, 36.5 mL CH4/0.500 g fermented DM, and 151.5 mL CO2/0.500 g fermented DM, respectively, compared to treatments T3 and T4. Under the conditions of this study, it was concluded that it is possible to replace traditional forages with up to 20% of A. mearnsii, without observing changes in the production of greenhouse gases with respect to the control treatment (0% of A. mearnsii); however, A. mearnsii is not usable because it significantly decreases rumen degradability of DM and OM, which would considerably affect the production in animals. [ABSTRACT FROM AUTHOR]

Stator limbatus is a phytophagous beetle native to warm regions of North and Central America, feeding on Fabaceae seeds and one of the most polyphagous species within the subfamily Bruchinae, here reported for the first time in Europe and on new hosts. Adult beetles emerged from Acacia spp. seeds collected in the islands of Corsica (France), and Sardinia (Italy). The wide presence in Sardinia and Corsica supports the hypothesis that this alien species was introduced several years ago. In both islands, S. limbatus emerged from Acacia mearnsii seeds, with infestation rates of up to 74.2 and 90.8% in 2019 and 2020, respectively. This seed beetle also emerged from two previously unreported host species, Acacia saligna and A. pycnantha, showing highest infestation rates of 4.0 and 95.1%, respectively. Both Acacia species are reported as new host associations with S. limbatus. Overall, seed infestation rates recorded in 2019 and 2020 indicate that S. limbatus is well established and that Mediterranean bioclimatic conditions are suitable for its population increase in size. This study lays the foundations for further research on known and potential host species and the spread and distribution of S. limbatus in Europe. [ABSTRACT FROM AUTHOR]

• In vitro antidiabetic screening of the three most prolific invasive plants are explored. • This is the first study to investigate cytotoxicity of Acacia cyclops extracts on a human cell-line (Caco-2). • Study validates therapeutic possibilities of Acacia spp. for diabetes treatment. • Presents a future alternative management solution to invasive plants in South Africa. 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 IC 50 of 10.45 ± 3.79 μg/ml and 2.35 ± 0.61 μg/ml followed by leaf extract depicting strong α-glucosidase (IC 50 of 3.64 ± 1.59 μg/ml) and moderate α-amylase (IC 50 of 17.67 ± 3.84 μg/ml) inhibition. The IC 50 values of all extracts were significantly (p < 0.05) lower than Acarbose (IC 50 of 330.71 ± 28.36 μg/ml) and Epigallocatechin gallate (IC 50 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. [ABSTRACT FROM AUTHOR]

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 (SHFP) in southern Tanzania which is the potential plantation in East Africa is under Acacia mearnsii invasion which threatens the productivity of the planted species, Pinus patula. This study aimed to gather information on the performance of Pinus patula by comparing areas invaded by Acacia mearnsii with the non-invaded areas in SHFP. The study used a combination of stratified and random sampling techniques to select sample plantation blocks and plots allocation, respectively. Data collected included survival, height, and diameter of Pinus patula in both invaded and non-invaded areas as well as Acacia mearnsii stem counts in invaded areas. The mean basal area, density, and volume of Pinus patula were subjected to paired sample T-test and relationship between the density of Acacia mearnsii and survival of Pinus patula were established by Pearson's correlation analysis in R software version 3.5.2. Results showed that survival of Pinus patula was decreasing as the density of Acacia mearnsii increased. Also, there was a significant difference in density, basal area and volume of Pinus patula between invaded and non-invaded areas with higher performance being in non-invaded areas. Results suggest that Acacia mearnsii has a negative effect on the performance of Pinus patula in both its growth and survival. This study has generated the information for which among others will help to formulate policies and strategies that will contribute to the effective and sustainable management of forest plantations that should incorporate invasive control measures to avoid the negative performance of desirable tree species. [ABSTRACT FROM AUTHOR]

Purpose The objective was to evaluate the agronomic performance of black wattle seedlings (Acacia mearnsii) grown on substrates with increasing proportions of biochar based on anaerobic sewage sludge (ASS-biochar). In addition, the present study proposed appropriate ranges for the main physical-hydraulic and chemical attributes of these substrates. Method The evaluated substrates included ten formulations with increasing proportions of ASS-biochar, combined with a "standard" mixture (organic compost, carbonized rice husk and vermiculite), in addition to three commercial substrates (references). The experimental design was randomized blocks, with four replications and eight plants per repetition. The physical-hydraulic and chemical attributes evaluated in all substrate formulations were: wet and dry density, total porosity, aeration space, easily available water, buffering water, available water, remaining water, pH and electrical conductivity (EC). The agronomic performance of the black wattle seedlings was evaluated through plant height, length of the root system, neck diameter, dry mass of aerial parts, dry mass of roots and Dickson's quality index. Results Biochar from anaerobic sewage sludge increased the chemical and physical-hydraulic quality of the substrates, particularly within the proportion of 45-50% of the substrate formulations, and thus positively affected the growth parameters of the black wattle plants. Conclusion The biochar produced from anaerobic sewage sludge is an efficient raw material to compose substrates for the production of seedlings. Transformation of anaerobic sewage sludge into biochar and its combination with other locally available raw materials can be considered a safe way of reusing this residue in agriculture. [ABSTRACT FROM AUTHOR]

The analysis of variance is the statistical test most used for comparison of three or more means simultaneously. Its application requires, however, the compliance to some assumptions, with main emphasis on normality of the data and homoscedasticity of variances. When such requirements are not met, one of the alternatives is the data transformation to enable the continuity of the experimental evaluation. With the proposition of the Tukey's data transformation system, understood as a power transformation system, i.e. the application of nth root on a data set (X⅟n) this statistical procedure has methodologically evolved to ensure such solutions. In the present research we proposed a complement to this system, denominated here as transformation in four steps, with inclusion of two hypothesis tests to evaluate normality and homoscedasticity. This was applied on experimental data to evaluate the amount of radiation available at soil level within stands of Acacia mearnsii De Wild. We have proposed a model for data transformation to simultaneously obtain homoscedasticity and normality. The methodology was appropriate to ensure these two statistical aspects on the experimental data, allowing comparison of eight treatments by conventional analysis of variance. [ABSTRACT FROM AUTHOR]

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. [ABSTRACT FROM AUTHOR]

Despite using antimycotic drugs in the treatment of dermatomycoses as an age long practice, the fungicidal activities of indigenous plants on spores of dermatophytes from germinating in vitro need to be investigated further. In this study, methanol extract of Acacia mearnsii was assessed for its antifungal activity against dermatophytic pathogenic fungi by agar diffusion and broth dilution methods. The cytotoxicity activity of the extract was determined by the brine shrimp lethality assay. The study showed that the mean ± standard deviation of the inhibition zones ranged between 13 and 24 ± 0.58 mg/ml and the activity of the extract was concentration dependent. While the minimum inhibitory concentration (MIC) was 0.3125 - 2.5 mg/ml, the minimum fungicidal concentration (MFC) values ranged between 0.3125 mg/ml and 5 mg/ml. The susceptibility of the yeast to the extract was more than those of the molds. The MIC of the yeasts ranged between 0.3125 and 1.25 mg/ml while those of the molds ranged between 0.625 and 2.5 mg/ml. The mechanism of antibiosis showed that the extract was 7.69% fungistatic and 92.31% fungicidal wielding more killing effects on the fungi than potentiating their growth. The cytotoxicity assay showed that the crude methanolic extract with the LC50 being 101.59 µg/ml was pharmacologically active and nontoxic (LC50 > 100 µg/ml). The antifungal activity of this plant can be exploited as an alternative or complementary means of treating fungal infections to eliminate fungal spread. The study further justified the folkloric use of A. mearnsii in the treatment of a variety of microbial infections. [ABSTRACT FROM AUTHOR]

The degree to which invasive Acacia species affect South Africa’s livestock production has received little attention. We investigated the ecological impacts of Acacia mearnsii invasion on forage quality and quantity and on soil resources, along A. mearnsii invasion gradients, on South African rangelands and the subsequent conditions following clearing. Grazing capacity was reduced by 72% in densely invaded sites, whereas clearing improved grazing capacity by 66% relative to densely invaded sites within 5 years. In densely invaded sites total grass species basal cover was reduced by up to 42%. As a result, A. mearnsii reduced grazing capacity, from 2 to 8 ha required to support one large stock unit (ha/LSU) in uninvaded and densely invaded sites, respectively. Soil moisture content was lower in densely invaded sites compared with lightly invaded and cleared sites. Plant litter increased from 1.3% to 4.2%, carbon content of the soil increased from 2.0% to 4.0% and nitrogen concentrations increased from 0.1% to 0.2% in response to invasion by A. mearnsii. Clearing resulted in improved grazing capacity within 5 years. These results also showed that, if left uncontrolled, wattle species can reduce livestock carrying capacity within montane grasslands in South Africa. EDITED BY James Aronson [ABSTRACT FROM AUTHOR]

Acacia mearnsii De Wilde is on the top 100 of the world's most invasive alien species and has successfully invaded many areas around the world. However, its distribution and expansion is seldom reported in China. This study for the first time conducted a survey on the new distribution of A. mearnsii at the Kunming Changshui Airport (Yunnan Province, China), through monitoring on population characteristics (number, density, height and ground diameter) and spatial distribution (spread distance). Our survey results show that A. mearnsii has spread rapidly across the airport. This study discusses three factors of environmental factors, human disturbance and weed characteristics behind this successful invasion. The species invasion has a strong potential to change the local vegetation structure, enhances the probability of bird strikes at the airport, and is vulnerable to invade new biogeographic regions if it is not controlled. Currently, eradication combined with mechanical control is considered to be the best option for control. Our study helps improve awareness about the potential risk of A. mearnsii invasion in other airports around China and the world. [ABSTRACT FROM AUTHOR]

This study examined whether the effects of the tanniferous extract of Acacia mearnsii on N partitioning in dairy cows and ammonia (NH 3) volatilization from their excreta are additive to that of the tanniferous legume sainfoin (Onobrychis viciifolia) and remain consistent when supplemented to different silage types with varying crude protein (CP) content. In a 6 × 6 Latin Square arrangement, six multiparous Holstein cows (milk yield: 36.6 ± 3.9 kg/d; 70 ± 13 d in milk) were assigned randomly to six treatments. The experiment included a 14-d adaptation and a 7-d data collection period, where intake, milk yield, and composition were recorded daily and excreta were collected. Cows had ad libitum access to one of six total mixed rations containing (dry matter [DM] basis) 750 g/kg DM silage. The silages were rich in either sainfoin (180 g/kg CP of DM), ryegrass (118 g/kg CP) or clover (220 g/kg CP). Each silage was supplemented with 20 g/kg DM of Acacia mearnsii extract or straw meal. The effects on N partitioning, ruminal volatile fatty acids (VFA) and microbiota, and NH 3 volatilization from slurry reconstituted from fresh urine and feces were determined. The sainfoin-based diet reduced the apparent digestibility of organic matter, acid detergent fiber, and N compared with the ryegrass- and clover-based diets (P < 0.001). Acacia reduced the DM intake (P < 0.05) and apparent digestibility of organic matter and N across all silage types (P < 0.01). The digestibility of neutral detergent fiber was reduced with sainfoin, and ryegrass with Acacia (Silage × Acacia interaction P < 0.05). Acacia reduced the ruminal acetate proportion (P < 0.05) but did not affect ruminal propionate and n-butyrate or the microbiota composition. With ryegrass, the rumen fluid had lower acetate (P < 0.001) and greater n-butyrate proportions (P < 0.01) compared to sainfoin and clover, lower propionate proportions as compared with sainfoin (P < 0.05), and the lowest blood urea N concentration (P < 0.001). Acacia reduced energy-corrected milk yield (P < 0.05). Milk protein content was reduced with the sainfoin diet (P < 0.05). Sainfoin (compared to clover) and Acacia supplementation shifted the N excretion from urine to feces and decreased urinary urea N excretion and NH 3 volatilization from the slurry (P < 0.05). The effects of the two tannin sources were widely additive in mitigating urinary urea N and NH 3 volatilization. The results illustrate that combinatory N-abatement measures based on different CT sources are efficient, but supplementing Acacia resulted in decreasing dry matter intake and milk production, while sainfoin supplementation resulted in lower organic matter digestibility. [Display omitted] • Two tannin sources, sainfoin and Acacia mearnsii , were studied in dairy cows. • Sainfoin and Acacia were additive in reducing urinary N-losses. • Acacia reduced ammonia volatilization from fresh slurry by up to 37%. • The latter effect was greater at high dietary protein content. • Acacia reduced performance and sainfoin reduced digestibility. [ABSTRACT FROM AUTHOR]

Acacia mearnsiiDe Wild (black wattle) is an important plantation species for tannin production and woodchip exports in South Africa and Brazil. This study provides an updated overview of the black wattle industries in both countries, including planted areas and land ownership, silviculture and management, bark extract production, woodchip exports, as well as key research and development issues. The current total planted area to black wattle is 110 000 ha in South Africa and c. 170 000 ha in Brazil. In both countries black wattle is mainly cultivated by farmers (c. 76–78% of the total area). Due to the high prices fetched by the wattle woodchips in the international market, black wattle is a profitable crop. In South Africa, the timber provides 85% of the revenue and the bark the other 15%, and thus the commercial emphasis has shifted from bark to timber. At present the only significant secondary products are charcoal and firewood.Acacia mearnsiibark tannins are used in the leather industry, adhesives for wood composites, water flocculants and specialty products for the chemical, food and beverage industries. The world demand for vegetable tannins has remained unchanged over the past two decades due to intense competition from synthetic tannins. South Africa produces about 45 000 t of bark extract annually, whereas Brazil produces 30 000–40 000 t. The annual value ofA. mearnsiiextract from South Africa and Brazil is about US$100 million. The total wattle woodchip exports from South Africa and Brazil in 2013 was 800 000 bone dry metric tonnes (BDMT) and 570 000 BDMT, respectively, with an estimated value of US$208 million.Acacia mearnsiioffers important economic advantages for pulp production (higher wood density and pulp yield, which translate into higher digester productivity and factory output), and is highly suitable for hardwood bleached kraft pulping, dissolving and semi-chemical pulps. These factors makeA. mearnsiia sought-after species and have ensured a sustained demand for wattle woodchips in the Japanese market, and today continue to attract new customers in emerging markets (China and India). The most important challenges for the black wattle industry in South Africa are (1) to maintain the wattle land base and improve productivity from the existing resource and (2) considering that black wattle is a highly labour-intensive crop and the recent increases in labour costs, it is necessary to revisit current silviculture practices from a costs–yield perspective and to develop mechanised harvesting/bark stripping systems. The Brazilian wattle industry faces important challenges in silviculture, tree improvement, and pests and diseases, which require further research and collaboration between the few players involved. It is important for both Brazil and South Africa to develop domestic markets for wattle solid wood as additional sources of income for the many farmers growing wattle. [ABSTRACT FROM AUTHOR]

ABSTRACT Concerns exist over increasing sediment yields in areas of South Africa with a Mediterranean climate that result from the clearing of invasive woody vegetation from steep slopes, as part of the Working for Water Programme. Erosion rates were monitored with erosion pins over a 26-month period. Measurements were made on slopes covered with indigenous fynbos vegetation, intact Acacia mearnsii stands (the invasive species) and on slopes from which A. mearnsii had been cleared either within the last 2 years or 11 years ago. Net erosion was observed at all sites following the largest storm during the monitoring period, whereas smaller storms were often accompanied by net deposition. Cleared locations showed the most variable response through time and sites with native fynbos vegetation the least. A stepwise multiple regression showed that vegetation cover, slope gradient and stone cover were the main variables affecting soil loss, but the relationship varied between sites and measuring periods. Soil loss was negatively related to vegetation cover and stone cover, as could be expected; the negative relationship with slope was more surprising. Stone cover, which increases with slope gradient, is considered to be an important control on soil loss. The findings of this study suggest that the rehabilitation of hillslopes invaded by alien woody vegetation needs to take into account the slow recovery of vegetation after initial clearing as, 11 years since clearing, significant erosion still occurs during severe storms. Copyright © 2012 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

There is need for documenting the long-term effects of plant invasions at the landscape scale. We investigated the possible catalytic effect of invasive Acacia mearnsii De Wild. on the colonization of rural landscapes by native plant species on Réunion Island (Mascarene Archipelago, Indian Ocean). Data were recorded from 182 circular plots of 50 m2 within a set of 48 large invasion patches, aged from 1 to 48+ years. Only eighteen native plant species were present in the invaded patches and these in only 21 of the 48 patches. The Acacia invasion patches colonized by native flora were older and closer to the closest forest remnant. Most invasion patches colonized by native species were located <200 m from forest remnants. Results are consistent with studies on colonization rates of nonindigenous forest plantations, which increase with age and decrease with distance to seeds sources. Yet, the rate of Acacia invasion patches colonized by native flora remained very low compared to studies on the colonization of exotic plantations in other tropical countries. We conclude that invasion patches of Acacia mearnsii are poor colonizing sites for native plant species. Allelopathy is suspected as one of the strongest factors, which prevent this colonization. [ABSTRACT FROM AUTHOR]

Abstract: Aboveground biomass was twice as high in mixtures of Eucalyptus globulus and Acacia mearnsii when compared to E. globulus monocultures after 11 years. This was attributed to increased nutrient availability and accelerated rates of N and P cycling in mixtures. This study examined whether the increase in aboveground biomass production was associated with an increase in total productivity (both above- and belowground), a change in C partitioning (from below to aboveground) or both. Total annual belowground C allocation (TBCA) was determined during year 11 in a mixed-species trial near Cann River, southeastern Australia. Monocultures of E. globulus (100%E) and A. mearnsii (100%A) and mixtures of these species (50%E:50%A) were planted in a replacement series. Using a conservation of mass approach, TBCA was estimated as soil carbon dioxide (CO2) efflux C minus the C input from aboveground litter plus changes in the C stored in soil, roots and the forest floor litter layer. Aboveground net primary production (ANPP) was also estimated to enable comparison of ratios of above and belowground fluxes between treatments. TBCA ranged from 14.6 to 16.3MgCha−1 year−1 and was not significantly different in 100%E, 50%E:50%A and 100%A. Higher ratios of ANPP:TBCA in the mixtures (0.41) than in either monoculture (100%A:0.28 100%E:0.31) indicated that trees in mixture partitioned a lower proportion of assimilated C belowground than those in monocultures. Since the mixture was as productive as monocultures belowground but more productive aboveground, it appears to be more productive overall and thus have the potential to increase C sequestration above that of monocultures. [Copyright &y& Elsevier]

Three assays, namely stomatal length measurements, counts of chloroplast numbers within the stomatal guard cells and flow cytometry, were used to confirm the ploidy of three diploid and three tetraploid Acacia mearnsii lines. The first two methods have previously been successful in identifying ploidy in this species, but they are indirect assessments. Flow cytometry directly quantifies the amount of DNA present in a sample, but has not been previously tested on A. mearnsii. It was decided to test the accuracy of all three methods by using the exact same plant material for each method. Results showed that each method correctly identified the ploidy of the diploid plant material tested as well as two of the three tetraploids tested. All three techniques identified the third tetraploid (C19/48/17) as a diploid, suggesting that its original classification was incorrect. From this study, all three techniques followed the same trend, confirming their accuracy for future research into ploidy identification of A. mearnsii. Flow cytometry has the advantage of providing a quick and efficient direct assessment of DNA in the sample, but is the most expensive. The other two techniques used (stomatal length measurements and counts of chloroplast numbers within the stomatal guard cells) are also accurate but are indirect methods and more time-consuming. [ABSTRACT FROM AUTHOR]