Peruvian traditional medicine in Milan (Italy). The case study of Minthostachys mollis: from ethnobotany to phytochemistry and biological activity

Ethnopharmacological relevance. Minthostachys mollis (Benth.) Griseb. (Lamiaceae) is an endemic Andean plant, commonly known as muña, and one of the most relevant in Peruvian traditional medicine[1,2]. In Peru, leaves-based infusions represent a folk remedy to alleviate high-altitude-related symptoms. Muña teas are also consumed in Italy by the Peruvian immigrant community as digestive, carminative, and antispasmodic, often as an alternative to conventional pharmacological treatments. Aim of the study. Within the project BE ETHNO[3], an urban ethnobotanical survey was conducted in Milan with the Peruvian community to document the traditional knowledge preservation. This study aims to investigate the chemical composition and the potential anti-inflammatory properties of the muña popular infusion. Materials and methods. Semi-structured interviews focused on medicinal plants. Aqueous (folk infusion) and ethanolic extracts were prepared using dried leaves imported from Peru and purchased in ethnic markets. An untargeted LC–MS analysis was performed to obtain a preliminary phytochemical profile of both extracts and to identify the main classes of metabolites. Preliminary anti-inflammatory activity of both extracts was evaluated in RAW264.7 murine macrophages challenged with lipopolysaccharide (LPS). Cells were treated with a range of concentrations and cytocompatibility was assessed by MTT assay. Results. Thirty-four informants were interviewed. M. mollis was the most frequently cited, mainly for gastrointestinal problems. Both extracts showed a rich phytochemical profile, characterized by free phenolic compounds, their glycosylated derivatives, and terpenes. The aqueous extract was cytocompatible up to 100µg/mL and significantly counteracted LPS-induced cytotoxicity at all dosages tested. The ethanolic extract was cytocompatible up to 12.5µg/mL, while only specific concentrations (1µg/mL, 3.12µg/mL) showed a protective effect. Conclusion. Overall, these findings depicted M. mollis as a relevant species of the Andean–Peruvian biocultural heritage to be considered as a source of new bioactive compounds with promising phytomedical applications. However, more research is needed to validate its traditional use.