ABSTRACT Plants have been reported as used by local populations to treat various infections for a long time, which has directed several pharmacological studies. The main aim of this work was to evaluate three plant selection criteria with better predictive power to detect extracts with antifungal action: (1) medicinal plants that are not used for indications of infection and inflammation; (2) plants with direct citations for inflammation, except for infection; (3) plants with direct citations for inflammation and infection selected quantitatively by Syndromic Importance Value (SIV). We tested the action of 23 hydroethanolic extracts of plants against the fungi Candida albicans, Cryptococcus neoformans, and Cryptococcus gattii and found no differences in the number of active extracts among the different strategies used, but activity quality varied. The extract of Anacardium occidentale presented fungicidal activity against the three analyzed fungi. At least five species - A. occidentale, Myracrodruon urundeuva, Poincianella pyramidalis, Anadenanthera colubrina var. cebil, and Mimosa oftalmocentra - presented fungistatic and fungicidal effects against all strains. Our findings indicate that selecting plants based on popular indications and quantitative prioritization techniques increases the chance of detecting potential antifungal candidates, and that the plants selected by these criteria were more effective against C. neoformans.

Human beings have accumulated rich experience with natural resources over time, but such knowledge can be strongly influenced by several factors, such as age, sex and occupation. This study focuses on the influence of these factors on knowledge of medicinal plants in a rural community in northeastern Brazil. Data were collected through semi-structured interviews with 102 people, with the number of plants and uses cited studied for quantitative analysis. Through this research, it was possible to show that the social variables studied (age, sex and informants occupation) have contributed to the formation of different patterns of knowledge regarding medicinal resources. The results indicate that awareness of this dynamic is necessary for the proper implementation of projects where the goal is the sustainable use of natural resources (because it indicates the different levels of knowledge within a community), for studies intended to discover new drugs (because it indicates the peculiarities of certain groups), and for biodiversity conservation strategies.