The efficacy of phytoextracts is equally affected by the extraction solvent and the extraction method. Details of the solvent type, concentration, density, and other characteristics are associated with the quality of the resultant extract. Some solvents have been found to be effective only on specific parts of plants. Industry has shown a growing interest in eco-friendly plant extracts for the formulation of medication, food additives, cosmetics, and agricultural products. This interest is aligned with the proven necessity of sustainability, marketability, and regulation of manufactured products in value chains. In this review, the literature on antioxidant compounds and activity of extracts from African medicinal plants is reviewed. Findings indicate that the use of ethanol, methanol, water, and to a lesser extent, acetone as solvents for the extraction of antioxidant compounds is common. The use of these solvents is supported by decisive selection of procedure, ideal temperature, duration, solvent pH, and the extracted plant parts. Fermentation enhances the antioxidant activity of aqueous extracts but reduces that of alcohol extracts. This is particularly essential in continents such as Africa, where water is available but alcohol is scarce. “Green” extraction technologies are not as successful as solvent extractions for use with African medicinal plants. There is a financial hurdle that results in a mismatch between academic research innovations and societal transmission to new technologies, as most communities are dominated by small-to-medium enterprises. Further studies on the extraction of antioxidants from African medicinal plants are recommended to guide the research and link it to ordinary African societies.

Greyia radlkoferi Szyszyl (Melianthaceae) is an indigenous southern African medicinal tree whose ethanolic leaf extracts have been shown to have anti‐tyrosinase activity that can treat skin hyperpigmentation in humans. However, there are differences in activity levels among the populations of plants, with some trees having higher anti‐tyrosinase activity than others. It is critical to generate high‐quality materials with consistent anti‐tyrosinase activity for long‐term production of cosmeceutical products. To overcome the variation observed, determining the appropriate phenological growth stages to harvest quality leaf materials for better activity could be a way to address the observed variation. Detailed phenological growth stages of G. radlkoferi were described according to the BBCH scale to identify the phenological developmental stages of the plant, such as bud development, leaf development, inflorescence emergence, heading, flowering, development of fruit, ripening or maturity of fruit and seed, and senescence. Temperature and precipitation affect the phenological growth stages of G. radlkoferi. Lower temperatures and precipitation in 2018 resulted in lower development of leaf and flower buds, whereas higher temperatures in 2019 and 2020 led to increased leaf and flower buds. It was observed that more accumulated heat units were needed for leaf development, flowering, and fruiting than for bud development, fruit ripening, and senescence. The highest anti‐tyrosinase activity was achieved in leaves harvested during the flowering growth stage (half maximal concentration) (IC ₅₀ 19.50 ± 2.710 μg/mL) compared to budding (IC ₅₀ 23.91 ± 4.017 μg/mL) and vegetative growth stage (IC ₅₀ 27.88 ± 3.100 μg/mL); lower IC ₅₀ value indicates higher anti‐tyrosinase activity.

Buddleja saligna and Euclea natalensis are widely used in traditional medicine and have ornamental, medicinal, and cosmeceutical value. However, propagation methods for these species remain largely undocumented, highlighting the need for sustainable propagation techniques to support their commercialization. Therefore, this study investigated the influence of temperature on seed germination and seedling emergence, as well as the effects of cutting position, growth medium, season, and plant growth regulator use on vegetative propagation success. Seed germination of B. saligna was highest at 25 °C (96%), with mean germination time (3.1 days), mean emergence time (3.9 days), germination index (145.2), shortest time to 50% germination (2.6 days), and shortest time to 50% emergence (3.98 days). However, the results were not significantly different from those at 20 °C and 30 °C. For E. natalensis, maximum germination (98%) occurred at 20 °C, with no significant differences from 25 °C and 30 °C. For B. saligna, significant interactions between season and cutting position affected leaf and bud formation. The highest rooting percentage (7%) was obtained on stem cuttings treated with Dynaroot^TM 3 (0.8% IBA) and planted in coco peat (M2). However, overall rooting success remained low across all treatments. For E. natalensis, no survival or rooting was observed in any treatment combination. Overall, seed propagation was more effective under the conditions tested than vegetative propagation, which showed low rooting success. Therefore, further research is needed to establish reliable protocols for vegetative propagation in both species.

Buddleja saligna and Euclea natalensis are widely used in traditional medicine and have ornamental and cosmeceutical value. However, propagation methods are scarce, highlighting the need for sustainable propagation techniques to support commercialization and ensure a consistent supply of high-quality material. Therefore, this study investigated the influence of temperature on seed germination and seedling emergence, as well as the effects of cutting position, growth medium, season, and the use of a plant growth regulator on the success of vegetative propagation. Seed germination of B. saligna was highest at 25 °C (96%), with optimal mean germination time (3.1 days), mean emergence time (3.9 days), germination index (145.2), shortest time to 50% germination (2.6 days), and shortest time to 50% emergence (3.98 days). However, results were not significantly different from 20 °C and 30 °C. For E. natalensis, maximum germination (98%) occurred at 20 °C, with no significant differences to 25 °C and 30 °C. For B. saligna, significant interactions between season and cutting position affected leaf and bud formation. The best rooting percentage (7%) was achieved by stem cuttings treated with Dynaroot^TM 3 (0.8% IBA) and planted in coco peat (M2). For E. natalensis, no survival or rooting was observed in any of the treatment combinations. Overall, seed propagation was more effective, but vegetative propagation is preferable for producing uniform high-quality extracts as seed propagation may introduce variation. Therefore, further research is needed to establish reliable vegetative propagation protocols for both species.