Bioactive Potential of Wild Plants from Gardunha Mountain: Phytochemical Characterization and Biological Activities

The plants used in folk medicine have been increasingly studied to identify their bioactive properties. Therefore, this study aimed to assess the bioactivity of the hydroethanolic extracts of plants collected in Gardunha Mountain, Portugal. Seven abundant and representative wild plants were studied: <i>Cistus salviifolius</i>, <i>Clinopodium vulgare</i>, <i>Coincya monensis</i>, <i>Glandora prostrata</i>, <i>Helichrysum stoechas</i>, <i>Rubia peregrina</i>, and <i>Umbilicus rupestris</i>. The phytochemical composition of the extracts was determined by UHPLC-timsTOF-MS and by spectrophotometric methods. The antioxidant, in vitro anti-inflammatory and antimicrobial activity and the biocompatibility of the extracts were tested. The extracts were predominantly composed of flavonoids and phenolic acids, such as gallic acid, neochlorogenic acid and quercetin glycosides. The <i>C. salviifolius</i> extracts demonstrated very strong antioxidant activity related to scavenging free radicals (AAI = 2.84 and 2.93). Regarding antimicrobial activity, the <i>H. stoechas</i> extract exhibited inhibitory effects, particularly against Gram-positive bacteria and yeasts (MIC = 0.008-0.5 mg/mL). The <i>C. monensis</i>, <i>R. peregrina</i>, and <i>U. rupestris</i> extracts showed low cytotoxicity (viability > 70%) in the highest concentration tested. These findings highlight <i>C. salviifolius</i> and <i>H. stoechas</i> as promising sources of novel bioactive compounds, particularly antimicrobials in controlling microbial growth and promoting associated health benefits, and underscore the value of traditional medicinal plants as a guide for pharmacological studies.