Climate change, expanding soil salinization, and the developing shortages of freshwater have negatively affected crop production around the world. Seawater and salinized lands represent potentially cultivable areas for edible salt-tolerant plants. In the present study, the effect of salinity stress on plant growth, mineral composition (macro-and micro-nutrients), and antioxidant activity in dune spinach (Tetragonia decumbens) were evaluated. The treatments consisted of three salt concentrations, 50, 100, and 200 mM, produced by adding NaCl to the nutrient solution. The control treatment had no NaCl but was sustained and irrigated by the nutrient solution. Results revealed a significant increase in total yield, branch production, and ferric reducing antioxidant power in plants irrigated with nutrient solution incorporated with 50 mM NaCl. Conversely, an increased level of salinity (200 mM) caused a decrease in chlorophyll content (SPAD), while the phenolic content, as well as nitrogen, phosphorus, and sodium, increased. The results of this study indicate that there is potential for brackish water cultivation of dune spinach for consumption, especially in provinces experiencing the adverse effect of drought and salinity, where seawater or underground saline water could be diluted and used as irrigation water in the production of this vegetable.

There are growing concerns about the chronic and acute effects of synthetic additives such as antibacterial, fragrances, colourants and stabilizing agents used in the production of various household products. Many household products and materials including cosmetic products are reportedly suspected to be carcinogenic with some acting as endocrine disruptors among other effects. Thus, environmental-friendly alternatives such as products that are rich in bioactive phytochemicals are becoming consumers' preferred choice especially in the beauty and cosmetic sector. 'Green' preparation of medicinal soaps devoid of any synthetic additives was made from underutilized tropical seed of Citrus sinensis seed oil and some natural additives comprising of natural honey, Ocimum gratissimum leaves extract, Moringa oleifera seed oil and coconut oil. Precisely, the seed oil of the underexplored C. sinensis was obtained via soxhlet extraction and saponified with natural lye solution at different ratios to produce soaps of varying characteristics. The incorporation of honey and Ocimum gratissimum leaf extract provided additional antimicrobial, antioxidant and fragrance properties. Physico-chemical parameters of the oil and soaps were determined following standard procedures while the fatty acid profile of the trans-esterified oil was determined using GC-MS. The antimicrobial potential of the oil and soaps were assessed using agar diffusion method at concentrations 200 mg/mL and below. Linoleic acid (36%) and oleic acid (27%) were the most prominent in C. sinensis seed oil. The soap had antimicrobial potential comparable to commercial product. The soap samples recorded highest anti-bacteria activities (22.0 ± 1.0-23.0 ± 1.0) against Staphylococcus aureus and Bacillus subtilis and notable anti-fungi activities (18.0 ± 1.0) against Penicillium notatum and Candida albicans. Additionally, the oil showed moderate anti-parasite (anit-toxoplasma gondii) activity (EC₅₀ ≤ 500 μg/mL) but with improved selectivity that precludes oxidative stress while the prepared medicinal soaps exhibited remarkable antioxidant property. The utilization of these locally sourced resources will prevent the daily introduction of synthetic antimicrobial and antioxidant chemicals into the environment. The initiative avail a sustainable production of environmentally-benign cosmetic products besides conversion of waste to wealth agrees which aligns with the Sustainable Development Goals (SDGs).

Although there are over 4000 potato cultivars in the world, only a few have been commercialized due to their marketability and shelf-life. Most noncommercialized cultivars are pigmented and found in remote regions of the world. White-fleshed potatoes are well known for their energy-enhancing complex carbohydrates; however, pigmented cultivars are potentially high in health-promoting polyphenolic compounds. Therefore, we reveal the comprehensive compositions of pigmented cultivars and associated potential health benefits, including their potential role in ameliorating hunger, food, and nutrition insecurity, and their prospects. The underutilization of such resources is a direct threat to plant-biodiversity and local traditions and cultures.

Context: Cola gigantea A. Chev. (Sterculiaceae) is an important medicinal tropical flora. Objective: The seed oil of C. gigantea, an underutilized tropical plant was investigated for its antioxidant, anti-inflammatory, anti-Toxoplasma, and cytotoxicity activities as well as the chemical composition. Materials and methods: The physicochemical parameters of the seed oil obtained via Soxhlet extraction was determined while the fatty acid and non-fatty acid component were analyzed by gas chromatography-mass spectrometry. The antioxidant activity was evaluated using 2,2-diphenyl-1-picrylhydrazyl (DPPH) and 2,2-azino-bis-(3-ethylbenzothiazoline-6-sulphonic acid) (ABTS) assays (10–50 µg/mL) while the anti-inflammatory property was determined through Cell Membrane Stabilization assay. The anti-parasite and cytotoxicity activity were evaluated (0–1000 µg/mL) using Toxoplasma gondii and mammalian cell line assays, respectively. Results: The oil had fatty acids which ranged from C-12 to C-23 with linoleic (18:2) and palmitic acids (16:0) being dominant. The oil had 89.41% unsaturated fatty acids with sterolic acid, an uncommon acetylenic fatty acid reported for the first time. Non-fatty acids obtained include cholesterol (2.12%), campesterol (14.12%), stigmasterol (34.07%) and β-sitosterol (49.68%). The oil had a significantly (p < 0.05) low scavenging activity against DPPH radicals (IC₅₀ > 50 µg/mL) compared with ascorbic acid. In contrast, the oil showed better activity against ABTS radicals (IC₅₀ 44.19 ± 6.27 µg/mL) compared with ascorbic acid or quercetin. Furthermore, the oil showed anti-T. gondii and dose-dependent cytotoxicity in HFF cells with selectivity index (IC₅₀/EC₅₀ < 1). Discussion and conclusions: The antioxidant potential of the oil suggests that it may serve as a potential source for various preparations for pharmaceuticals and cosmeceuticals.

The overexploitation of wild plants for medicinal uses and conventional agricultural farming methods, which use high amounts of water, fertilizers, and pesticides, have had devastating environmental consequences. This study aimed to evaluate the prospects of using aquaponics and hydroponics as alternative approaches to soil cultivation by comparing the crop yields, secondary metabolite contents, and the antifungal activities of ethanol extracts of Helichrysum odoratissimum (L.) Sweet, a widely used medicinal plant species in Southern Africa. Six-week-old H. odoratissimum seedlings were grown in aquaponic and hydroponic systems. The growth parameters, secondary metabolite contents, and antifungal activity against Fusarium oxysporum were assessed. The results for crop yield (plant height, fresh and dry weights) and the tissue nutrient contents did not change substantially (p > 0.05) between aquaponic and hydroponic treatments. Gas chromatography–mass spectrometry (GC–MS) analysis showed that monoterpenes and sesquiterpenes were the most abundant compounds in H. odoratissimum; however, no statistical difference was observed among the field, hydroponic, and aquaponic plants (DF = 2; χ² = 2.67; p > 0.05). While there was no significant difference in polyphenol contents among the three treatments, remarkably, the flavonol contents in the leaves varied significantly (DF = 2; χ² = 6.23; p < 0.05) among the three treatments. A higher flavonol content occurred in leaves from the hydroponic system than in leaves from the aquaponic (p < 0.05) and field (p > 0.05) systems. The MIC results showed that the ethanolic extract of H. odoratissimum was fungistatic against F. oxysporum; however, this effect was more prominent in the ethanol extracts of plants grown in the aquaponic system, with a mean MIC value of 0.37 ± 0.00 mg/mL The key findings of this study are that aquaponically cultivated plants exhibited the best antifungal activity, while higher total flavonol contents occurred in the hydroponically cultivated plants. In conclusion, aquaponics and hydroponics performed better or similar to field cultivation and are viable alternative methods for cultivating H. odoratissimum plants.