The historical use of plants as sources of natural compounds has persisted over time. Increasing the intake of bioactive substances shows significant potential for promoting overall well-being and health. This study delves into the pigments, phenolic composition, and profile, along with antioxidant properties, of leaf extracts rich in bioactives from plants in the Azores region, contributing to sustainable primary food production. Analyses encompassed chlorophylls, carotenoids, total phenols, ortho-diphenols, and flavonoids, as well as antioxidant capacity assessment, polyphenolic profiling, and quantification. Psidium guajava L. and Smallanthus sonchifolius (Poepp.) H.Rob. exhibited elevated chlorophyll content, while Colocasia esculenta (L.) Schott displayed the highest carotenoid levels. Annona cherimola Mill., Eriobotrya japonica (Thunb.) Lindl, and Psidium guajava L. demonstrated pronounced total phenols, ortho-diphenols, and flavonoids. These findings align with heightened antioxidant capacity. HPLC–DAD (high-performance liquid chromatography with diode-array detection) characterization unveiled elevated hydroxycinnamic acids in E. japonica and Ipomea batatas (L.) Lam. compared to A. cherimola Mill., while C. esculenta exhibited increased flavone content. Among the quantified compounds, flavonols were the ones that predominantly demonstrated contribution to the antioxidant capacity of these leaves. This research highlights Azorean leaf plants’ antioxidant potential, fostering natural product development for better health.

Over the years, there has been a tendency for an increase in global obesity. The World Health Organization’s (WHO) 2024 report states that in 2019, more than one billion people were obese, and this condition was responsible for five million deaths, being that obesity is more prevalent among adults compared to adolescents and children. Obesity is a chronic disease characterized by alterations in adipose tissue. When excessive food is consumed and energy expenditure is low, adipose tissue undergoes hypertrophy and hyperplasia. This process activates B cells and induces the transition of anti-inflammatory M2-like macrophages into pro-inflammatory M1-like macrophages. B cells, acting as inflammatory mediators, stimulate pro-inflammatory CD8+ T cells, and promote macrophage infiltration into tissues. This condition triggers inflammation, increases oxidative stress, and ultimately leads to cellular death. During inflammation, an increase of pro-inflammatory cytokines occurs along with a decrease of anti-inflammatory cytokines. By contrast, the increase of oxidative stress is related to an increase of reactive oxygen species (ROS), oxidation of biomolecules, and a decrease in antioxidants. This mechanism for obesity can be mitigated through several healthy lifestyle changes, primarily including regular physical activity and healthy eating. These factors help reduce pro-inflammatory mediators and ROS, lowering inflammation and oxidative stress. Therefore, this review article focuses on studying the bioactive compounds present in the edible leaves of Annona cherimola Mill., Ipomoea batata (L.) Poir., Colocasia esculenta (L.) Schott, Eriobotrya japonica, Cymbopogon citratus, Psidium guajava (L.), and Smallanthus sonchifolius to evaluate their effects on the mechanisms involved in obesity.

Eriobotrya japonica (Thunb.) Lindl. leaves are rich in polyphenolic compounds, yet their toxicological effects in aquatic models remain poorly understood. This study evaluated the impact of a hydroethanolic E. japonica leaf extract on zebrafish embryos through the use of morphological, behavioral, and biochemical parameters. The 96 h LC₅₀ was determined as 189.8 ± 4.5 mg/L, classifying the extract as practically non-toxic, according to OECD guidelines. Thereby, embryos were exposed for 90 h to 75 and 150 mg/L concentrations of the E. japonica leaf extract. While no significant effects were noted at the lowest concentration of 150 mg/L, significant developmental effects were observed, including reduced survival, delayed hatching, underdevelopment of the swim bladder, and retention of the yolk sac. These malformations were accompanied by marked behavioral impairments. Biochemical analysis revealed a concentration-dependent increase in superoxide dismutase (SOD) and catalase (CAT) activity, suggesting the activation of antioxidant defenses, despite no significant change in reactive oxygen species (ROS) levels. This indicates a potential compensatory redox response to a pro-oxidant signal. Additionally, the acetylcholinesterase (AChE) activity was significantly reduced at the highest concentration, which may have contributed to the observed neurobehavioral changes. While AChE inhibition is commonly associated with neurotoxicity, it is also a known therapeutic target in neurodegenerative diseases, suggesting concentration-dependent dual effects. In summary, the E. japonica leaf extract induced concentration-dependent developmental and behavioral effects in zebrafish embryos, while activating antioxidant responses without triggering oxidative damage. These findings highlight the extract’s potential bioactivity and underscore the need for further studies to explore its safety and therapeutic relevance.