Antifungal and antichemotactic activities and quantification of phenolic compounds in lipophilic extracts of Hypericum spp. native to South Brazil

Abstract

Plants of the Hypericum genus are a notable source of new therapeutic agents including antimicrobial and anti-inflammatory. This study reports the antifungal and antichemotactic activities of the lipophilic extracts of five Hypericum species (H. caprifoliatum Cham. & Schlecht., H. carinatum Griseb., H. linoides A. St.-Hil., H. myrianthum Cham. & Schlecht. and H. polyanthemum Klotzsch ex Reichardt) native to South Brazil. Tests were performed using the broth microdilution assay against 10 species of pathogenic yeasts and neutrophils migration inhibition method, respectively. All samples exhibited a broad spectrum of antifungal action as well as reduced neutrophils migration. H. carinatum, H. linoides and H. myrianthum extracts presented the lowest value of minimum inhibitory concentration against Cryptococcus neoformans (MIC≤15.6μg/mL), Rhodotorula mucilaginosa (MIC≤62.5μg/mL), Candida glabrata and Candida tropicalis (MIC range=1.9–250μg/mL). The antichemotactic effect varied from 60 to 100% at concentrations of 0.31–10.0μg/mL. The results of analyses by HPLC demonstrated a strong correlation between the phenolic compounds and the antifungal/anti-inflammatory activities. The extracts that presented high amounts of the dimeric phloroglucinol uliginosin B, japonicin A and hyperbrasilol B were the most active. Thus, Hypericum extracts show potential as source of new anti-infectives and anti-inflammatory drugs.