Search Results (16)

Phytotechnologies offer sustainable solutions for remediating mine residues by combining site rehabilitation with the potential recovery of secondary and critical raw materials (SRMs and CRMs, respectively), contributing to resource efficiency strategies. This study explored the direct propagation of Atriplex halimus unrooted cuttings into metal-contaminated mine tailings, assessing survival, biomass production, and trace metal accumulation. Treatments were carried out on mine tailings, with and without the addition of organic and inorganic amendments, and on commercial soil as a control. After an 8-week preliminary trial, Atriplex halimus demonstrated moderate survival and growth without phytotoxic symptoms, despite elevated trace metal concentrations. Significant accumulation of zinc, lead, and cadmium as model contaminants in the biomass of Atriplex halimus (up to 495.4, 31.9, and 1.2 mg kg⁻¹, respectively), as well as magnesium and manganese as model CRMs (2081 and 87.8 mg kg⁻¹, respectively) was observed in aerial tissues, comparable with traditional, though more labor-intensive propagation methods. Plants’ ability to accumulate metals was high in the presence of amendments added to promote biomass growth. These results highlight the significance of direct propagation by unrooted cuttings as a promising, low-cost strategy to initiate site restoration in metal-contaminated areas and warrant further investigation under field conditions and over longer durations. Full article

The Spiny saltbush (Rhagodia spinscens) is a halophyte species with the potential to provide natural ingredients used in food and pharmaceutical industries. In food and pharmaceutical applications, drying is necessary to maintain shelf-life, which reduces phytonutrient content. In this study, changes in the nutritional composition, phenolic and carotenoid profiles of radical antioxidant scavenging activity [(2,2′-azino-bis(3-ethylbenzothiazoline-6-sulfonic acid)(ABTS)], antioxidant power [ferric reducing antioxidant ability assay (FRAP)], and cytotoxicity of freeze- and oven-dried (55 °C for 24 h) spiny saltbush were determined. Sodium (4.72 g/100 g dry weight (DW), potassium (6.86 g/100 g DW), calcium (4.06 g/100 g DW), zinc (372 mg/kg DW) and protein content were higher in oven-dried samples than freeze-dried samples. Ultra-performance liquid chromatography–mass spectrometry analysis detected 18 metabolites in saltbush extracts. Partial Least-Squares Discriminant Analysis, Hierarchical Cluster Analysis, and Variable Importance in Projection discriminated between freeze-dried and oven-dried samples. Freeze-dried samples retained more individual metabolites than oven-dried samples, while oven-dried samples had higher antioxidant activity (ABTS and FRAP), lutein, trans-β carotene, and cis-β-carotene. Correlation analysis identified potential antioxidant candidates between phenolic and carotenoid compounds. Neither freeze-dried nor oven-dried spiny saltbush samples showed cytotoxicity. The study uncovered changes in phytonutritional compounds after the oven and freeze-drying spiny saltbush, a potential salt alternative and functional ingredient for the food industry. Full article

Cultivating edible salt-tolerant plants (halophytes) for human consumption is increasingly important due to climate change and soil salinization, and offers sustainable agricultural solutions. Optimizing seed germination, the crucial initial stage of crop growth, is essential for enhancing crop production. This study aimed to optimize the germination of edible halophytes under greenhouse conditions, focusing on select soil (salinity and substrate) and non-soil-related factors (chemical and mechanical treatments). The target species were selected for their commercial value and included Mesembryanthemum crystallinum L. (crystalline iceplant), Salicornia ramosissima J. Woods (sea asparagus), Medicago marina L. (sea medick), Ammophila arenaria (L.) Link (European beachgrass), Portulaca oleracea L. (common purslane), and Atriplex halimus L. (Mediterranean saltbush). Salinity negatively impacted germination rates (GRs) and delayed mean germination time (MGT) across species. P. oleracea had the highest GR (95.6%) in coco peat under freshwater irrigation, and the shortest MGT (5.2 days). A. halimus did not germinate under the tested conditions. Scarification with sulfuric acid improved the GR of M. marina by 42.2%, while scarification with ultrasounds improved the GR of A. arenaria by 35.5%. Our results indicate that the choice of substrate and the application of specific treatments like scarification can significantly improve the germination of certain halophyte species under variable saline conditions. Full article

Halophytes are considered emerging functional foods as they are high in protein, minerals, and trace elements, although studies investigating halophyte digestibility, bioaccessibility, and intestinal absorption are limited. Therefore, this study investigated the in vitro protein digestibility, bioaccessibility and intestinal absorption of minerals and trace elements in saltbush and samphire, two important Australian indigenous halophytes. The total amino acid contents of samphire and saltbush were 42.5 and 87.3 mg/g DW, and even though saltbush had a higher total protein content overall, the in vitro digestibility of samphire protein was higher than the saltbush protein. The in vitro bioaccessibility of Mg, Fe, and Zn was higher in freeze-dried halophyte powder compared to the halophyte test food, suggesting that the food matrix has a significant impact on mineral and trace element bioaccessibility. However, the samphire test food digesta had the highest intestinal Fe absorption rate, whereas the saltbush digesta exhibited the lowest (37.7 vs. 8.9 ng/mL ferritin). The present study provides crucial data about the digestive “fate” of halophyte protein, minerals, and trace elements and increases the understanding of these underutilized indigenous edible plants as future functional foods. Full article

Atriplex spp. (saltbush) is known to survive extremely harsh environmental stresses such as salinity and drought. It mitigates such conditions based on specialized physiological and biochemical characteristics. Dehydrin genes (DHNs) are considered major players in this adaptation. In this study, a novel DHN gene from Azrak (Jordan) saltbush was characterized along with other Atriplex species from diverse habitats. Intronless DHN-expressed sequence tags (495–761 bp) were successfully cloned and sequenced. Saltbush dehydrins contain one S-segment followed by three K-segments: an arrangement called SK3-type. Two substantial insertions were detected including three copies of the K2-segemnet in A. canescens. New motif variants other than the six-serine standard were evident in the S-segment. AhaDHN1 (A. halimus) has a cysteine residue (SSCSSS), while AgaDHN1 (A. gardneri var. utahensis) has an isoleucine residue (SISSSS). In contrast to the conserved K1-segment, both the K2- and K3-segment showed several substitutions, particularly in AnuDHN1 (A. nummularia). In addition, a parsimony phylogenetic tree based on homologs from related genera was constructed. The phylogenetic tree resolved DHNs for all of the investigated Atriplex species in a superclade with an 85% bootstrap value. Nonetheless, the DHN isolated from Azraq saltbush was uniquely subclustred with a related genera Halimione portulacoides. The characterized DHNs revealed tremendous diversification among the Atriplex species, which opens a new venue for their functional analysis. Full article

Atriplex dimorphostegia (Saltbush) is an annual halophytic shrub that is widely distributed across various parts of Asia. The current study is the first to report the metabolites profile of the total ethanol extract of the aerial parts of A. dimorphostegia (TEAD), and its anabolic activity together with the isolated 20-hydroxyecdysone (20-HE) in orchidectomized male rats. TEAD was analyzed and standardized utilizing UPLC-PDA-ESI–MS/MS and UPLC-PDA-UV techniques, resulting in tentative identification of fifty compounds including polyphenols, steroids and triterpenoids. In addition, 20-HE was quantified, representing 26.79 μg/mg of the extract. Phytochemical investigation of TEAD resulted in the isolation of 20-HE from the ethyl acetate fraction (EFAD) and was identified by conventional spectroscopic methods of analysis. Furthermore, the anabolic effect of the isolated 20-HE and TEAD was then evaluated using in silico and in vivo models. Molecular docking experiments revealed in vitro selectivity of 20-HE towards estrogen receptors (ERs), specifically ERβ over ERα and androgenic receptor (AR). The anabolic efficacy of TEAD and 20-HE was studied in orchidectomized immature male Wistar rats using the weight of gastrocnemius and soleus muscles. The weights of ventral prostate and seminal vesicles were used as indicators for androgenic activity. Rats administered 20-HE and TEAD showed a significant increase (p = 0.0006 and p < 0.0001) in the net muscle mass compared to the negative control, while the group receiving TEAD showed the highest percentage among all groups at p < 0.0001. Histopathological investigation of skeletal muscle fibers showed normal morphological structures, and the group administered 20-HE showed an increase in cross sectional area of muscle fibers comparable to methandienone and testosterone groups at p > 0.99. A. dimorphostegia exhibited promising anabolic activity with minimal androgenic side effects. Full article

Polyphenols are considered vital bioactive compounds beneficial for human health. The Australian flora is enriched with polyphenols which are not fully characterized yet. Thus, the main objective of this study was to identify and characterize the Australian native sandalwood nuts, wattle seeds, lemongrass, and old man saltbush for phenolic compounds and their antioxidant activities. In this study, we tentatively identified a total of 155 phenolic compounds including 25 phenolic acids, 55 flavonoids, 22 isoflavonoids, 22 tannins, 22 lignans, 33 stilbenes, 33 coumarins and derivatives, 12 tyrosols and derivatives, and 6 phenolic terpenes. The highest total phenolic content (TPC) (15.09 ± 0.88 mg GAE/g) was quantified in lemongrass, while the lowest TPC (4.17 ± 0.33 mg GAE/g) was measured in wattle seeds. The highest total flavonoid content (TFC) and total condensed tannins (TCT) were measured in lemongrass and wattle seeds, respectively. A total of 18 phenolic metabolites were quantified/semi-quantified in this experiment. Lemongrass contains a vast number of phenolic metabolites. Full article

Managed plantations of saltbush have the potential to increase the productivity and climate resilience of the farming systems of the low rainfall areas of the world, where livestock are important. The objective was to dynamically simulate the behaviour of grazing saltbush plantations with a new modelling capacity in the APSIM framework to enable the dynamic grazing of forage systems. Scenarios simulated included: the choice of plant species growing in the interrow area between shrub-rows, density of saltbush spatial arrangement, locations with different climates and soils, and grazing strategy by sheep. Comparisons of scenarios across systems were insightful during rainfall years when the shrub systems are of high value (i.e., driest/lowest 20% rainfall years in the simulation period). Overall, the efficient grazing of shrubs by dry sheep with little supplementary feeding, required the availability of a large amount of low quality interrow. Shrub plantations with an interrow of standing oats required least supplementation. Summer grazing was the optimal time for grazing shrub plantations in low rainfall years. Plantations with more shrubs relative to interrow increased the need for supplementary feeding but reduced the variation between years. This is one of the first uses of systems modelling to explore forage shrub system designs that maximise the grazing value of shrub plus interrow. Full article

Atriplex halimus L., also known as Mediterranean saltbush, and locally as “Lgtef”, an halophytic shrub, is used extensively to treat a wide variety of ailments in Morocco. The present study was undertaken to determine the antioxidant activity and cytotoxicity of the ethanolic extract of A. halimus leaves (AHEE). We first determined the phytochemical composition of AHEE using a liquid chromatography (LC)–tandem mass spectrometry (MS/MS) technique. The antioxidant activity was evaluated using different methods including DPPH scavenging capacity, β-carotene bleaching assay, ABTS scavenging, iron chelation, and the total antioxidant capacity assays. Cytotoxicity was investigated against human cancer breast cells lines MCF-7 and MDA-MB-231. The results showed that the components of the extract are composed of phenolic acids and flavonoids. The DPPH test showed strong scavenging capacity for the leaf extract (IC₅₀ of 0.36 ± 0.05 mg/mL) in comparison to ascorbic acid (IC₅₀ of 0.19 ± 0.02 mg/mL). The β-carotene test determined an IC₅₀ of 2.91 ± 0.14 mg/mL. The IC₅₀ values of ABTS, iron chelation, and TAC tests were 44.10 ± 2.92 TE µmol/mL, 27.40 ± 1.46 mg/mL, and 124 ± 1.27 µg AAE/mg, respectively. In vitro, the AHE extract showed significant inhibitory activity in all tested tumor cell lines, and the inhibition activity was found in a dose-dependent manner. Furthermore, computational techniques such as molecular docking and ADMET analysis were used in this work. Moreover, the physicochemical parameters related to the compounds’ pharmacokinetic indicators were evaluated, including absorption, distribution, metabolism, excretion, and toxicity prediction (Pro-Tox II). Full article

Intertidal vegetation provides important ecological functions, such as food and shelter for wildlife and ecological services with increased coastline protection from erosion. In cold temperate and subarctic environments, the short growing season has a significant impact on the phenological response of the different vegetation types, which must be considered for their mapping using satellite remote sensing technologies. This study focuses on the effect of the phenology of vegetation in the intertidal ecosystems on remote sensing outputs. The studied sites were dominated by eelgrass (Zostera marina L.), saltmarsh cordgrass (Spartina alterniflora), creeping saltbush (Atriplex prostrata), macroalgae (Ascophyllum nodosum, and Fucus vesiculosus) attached to scattered boulders. In situ data were collected on ten occasions from May through October 2019 and included biophysical properties (e.g., leaf area index) and hyperspectral reflectance spectra ($R_{rs}\left(\lambda \right)$). The results indicate that even when substantial vegetation growth is observed, the variation in $R_{rs}\left(\lambda \right)$ is not significant at the beginning of the growing season, limiting the spectral separability using multispectral imagery. The spectral separability between vegetation types was maximum at the beginning of the season (early June) when the vegetation had not reached its maximum growth. Seasonal time series of the normalized difference vegetation index (NDVI) values were derived from multispectral sensors (Sentinel-2 multispectral instrument (MSI) and PlanetScope) and were validated using in situ-derived NDVI. The results indicate that the phenology of intertidal vegetation can be monitored by satellite if the number of observations obtained at a low tide is sufficient, which helps to discriminate plant species and, therefore, the mapping of vegetation. The optimal period for vegetation mapping was September for the study area. Full article

This study aimed to use organic fertilizers, e.g., compost and manures, and a halophytic plant [wavy-leaved saltbush (Atriplex undulata)] to remediate an agricultural soil polluted with toxic elements. Compost or manure (1% w/w) was added to a polluted soil in a pot trial. The application of the organic fertilizer, whether compost or manure, led to a significant improvement in the growth of the tested plant. From the physiological point of view, the application of organic fertilizers to polluted soil significantly increased the content of chlorophyll, carotenoid, and proline and, furthermore, led to a clear decrease in malondialdehyde (MDA) in the plant leaves. The highest significant values of organic carbon in the polluted soil (SOC) and cation exchange capacity (CEC) were found for the soil amended by compost and planted with wavy-leaved saltbush. Manure significantly reduced the soil pH to 7.52. Compost significantly decreased Zn, Cu, Cd, and Pb availability by 19, 8, 12, and 13%, respectively, compared to the control. On the other hand, manure increased Zn, Cu, Cd, and Pb availability by 8, 15, 18, and 14%, respectively. Compost and manure reduced the bioconcentration factor (BCF) and translocation factor (TF) of Cd and Pb. Compost was more effective in increasing the phytostabilization of toxic metals by wavy-leaved saltbush plants compared to manure. The results of the current study confirm that the application of non-decomposed organic fertilizers to polluted soils increases the risk of pollution of the ecosystem with toxic elements. The cultivation of contaminated soils with halophytic plants with the addition of aged organic materials, e. g., compost, is an effective strategy to reduce the spreading of toxic metals in the ecosystem, thus mitigating their introduction into the food chain. Full article

High temperatures and water scarcity are among the main obstacles to producing fodder in arid regions. Saltbush shrubs are used for livestock in many arid regions, especially in saline conditions, due to their high salt tolerance. The produced forage materials under these saline conditions are often low in quantity and quality. This article presents field studies that were conducted for two growing seasons to evaluate the forage yield and quality of river saltbush (Atriplex amnicola Paul G. Wilson) as a function of compost application. The plants were cultivated in saline soil (15 dS m⁻¹), and compost was added at four rates (0, 5, 10, and 15 t ha⁻¹). River saltbush plant produced 9.23−15.60 t ha⁻¹ of stems and 4.25−7.20 t ha⁻¹ of leaves yearly (over all the treatments). The crude protein (CP) ranged between 48−70 g kg⁻¹ in the stems and between 160−240 g kg⁻¹ in the leaves (over all the treatments). The forage yield, crude protein, dry matter, and mineral contents of the tested plant increased significantly (p < 0.05) due to compost addition. The application of 5, 10, and 15 t ha⁻¹ of compost reduced the Na⁺ concentrations in the leaves by 14, 16, and 19% (as means of two years) compared with the control. In the same trend, these rates reduced the oxalate concentrations in the leaves by 38, 30, and 29% (as means of two years) compared with the control. Our results show that compost application improves the activity of polyphenol oxidase (PPO) and catalase (CAT). Compost reduces the adverse impacts of soil salinity by improving the photosynthesis process and increasing the activity of antioxidant defense. Compost also enhances the growth of river saltbush plants cultivated in saline soils, thus, enhancing their value as animal feed. Halophyte plants can be used to utilize saline soils that are not suitable for traditional production. Compost addition is a good agricultural strategy to increase growth and reduce the negative effects of salts. Full article

In recent years, edible halophytes have received more attention due to their ability to tolerate a wide range of salinities. In Australia, halophytes are used in a broad range of applications by Indigenous communities—in traditional cuisine, as livestock feed, and for soil bioremediation. However, very limited scientific information is available on the nutritional profiles and potential bioactivity of halophyte species. Therefore, the present study assessed the nutrient and phytochemical composition of Australian-grown Seapurslane (SP) (Sesuvium portulacastrum), Old Man Saltbush (SB) (Atriplex nummularia), and Seablite (SBL) (Suaeda arbusculoides) to better understand their nutritional value and potential bioactivity. SB and SP contained more (p < 0.05) fibre than commercial Australian baby spinach (same plant family) which was used as a reference (41.5 vs. 40.4 vs. 33.4 g/100 g dry weight (DW)). Furthermore, these plants can be considered as valuable sources of essential minerals (Ca, Fe, Mg and Na) and trace elements; specifically, SBL had the highest content of Ca and Fe. SB had the highest protein (20.1 g/100 g DW) and fat (2.7 g/100 g DW) content compared to the other studied halophytes. The fatty acid profile consisted mainly of palmitic, stearic, oleic, linoleic, and α-linolenic acids. A strong antioxidant capacity (total phenolic content and DPPH radical scavenging capacity) indicated that (poly) phenolic compounds are most likely the predominant phytochemicals in this species. These initial results are promising and suggest that Australian indigenous edible halophytes may have the potential to be utilized as functional food ingredients. Full article

Plant foods play a vital role in human nutrition due to their diverse range of macro- and micro-nutrients, fibre and phytochemicals. However, more than 90% of the plant-food demand is satisfied by less than 0.1% of the edible plant species available. Moreover, none of the highly consumed ‘food-plants’ can survive without freshwater irrigation. As the world’s population rises and food sources become limited, alternative avenues for satisfying the world’s food demand are necessary. This persistent situation urges the domestication of wild terrestrial salt tolerant (halophytes) edible plants, of which saltbush (SB) was found to have a long history of use as animal feed and soil erosion control, while very little scientific information is available on its nutritional profile and dietary relevance. Therefore, the present study assessed the nutrient and phytochemical composition of Australian grown oldman SB (Atriplex nummularia) leaves to better understand its nutritional ‘value’ and potential bioactivity. The proximate results showed that SB leaves were rich in protein (20.1 ± 0.18 g/100 g DW), fibre (41.5 ± 0.20 g/100 g DW) and minerals (particularly Ca (1.44 ± 0.03 g/100 g DW), Na (4.13 ± 0.02 g/100 g DW), Mg (0.90 ± 0.01 g/100 g DW), and Fe (11.68 ± 0.35 mg/100 g DW). These initial findings provide important nutritional information to a very promising plant source that could be used alone or synergetic with other foods (e.g., alternative protein and/or fiber source, potential salt substitute). However, further studies need to be carried out to determine the complete nutritional profile of oldman SB leaves, the bioaccessibility/bioavailability of its main nutrients and phytochemicals as well as consumer acceptance in order to develop SB based food products. Full article

Dipodomys microps, the chisel-toothed kangaroo rat, is heralded as one of few mammalian herbivores capable of dietary specialization. Throughout its range, the diet of D. microps is thought to consist primarily of Atriplex confertifolia (saltbush), a C₄ plant, and sparing amounts of C₃ plants. Using stable isotopes of carbon and nitrogen as natural diet tracers, we asked whether D. microps is an obligate specialist on saltbush. We analyzed hair samples of D. microps for isotopes from historic and recent museum specimens (N = 66). A subset of samples (N = 17) from 2017 that were associated with field notes on plant abundances were further evaluated to test how local saltbush abundance affects its inclusion in the diet of D. microps. Overall, we found that the chisel-toothed kangaroo rat facultatively specializes on saltbush and that the degree of specialization has varied over time and space. Moreover, saltbush abundance dictates its inclusion in the diet. Furthermore, roughly a quarter of the diet is comprised of insects, and over the past century, insects have become more prevalent and saltbush less prevalent in the diet. We suggest that environmental factors such as climate change and rangeland expansion have caused D. microps to include more C₃ plants and insects. Full article