The diffuse and invasive weed Oxalis pes-caprae L.: From botany to chemical, functional and ecological interactions with soil and organisms

Oxalis pes-caprae L. is a trystilous, synanthropic, and edible herbaceous plant of the family Oxalidaceae. Originally native to South Africa, it has now become naturalized in many temperate regiones, primarily as a result of its previous cultivation as an ornamental and edible plant. Its biomass is rich in secondary metabolites – particularly organic acids derivatives, phenolic compounds, and polyphenols - which endow it with nutritional and pharmacological potential, suggesting its applicability in the food and nutraceutical industries. This review critically compiles and analyzes existing data on the chemical composition of O. pes-caprae, alongside biological assays that evaluate its antimicrobial and therapeutic properties, particularly for degenerative human diseases. Although the species is considered invasive in many regions, effective eradication remains difficult due to its ecological adaptability. Its resilience is further enhanced by symbiotic relationships with diazotrophic and oxalotrophic bacteria, which facilitate its survival in degraded and polluted environments, positioning it as a potential candidate for phytoremediation. The limited but promising data regarding its role in environmental decontamination are discussed.