Paepalanthus spp: antimycobacterial activity of extracts, methoxylated flavonoids and naphthopyranone fractions

Paepalanthus spp., Eriocaulaceae, are native plants from Brazil known as "sempre-vivas" (everlasting flowers). In this work, we evaluated the potential anti-mycobacterial activity of two methoxylated flavonoids (flavonoid 7-methylquercetagetin and 7-methylquercetagetin-4'-O-β-D-glucopyranoside) isolated and identified from P. latipes and the naphthopyranone fractions from P. bromeliodes ethanolic extracts. The MIC value of 500 μg/mL was verified for all compounds tested against M. tuberculosis H37Rv. For M. avium, the MIC value ranged from 1000-2000 μg/mL excepting to naphthopyranone fractions with MIC of 500 μg/mL. This is the first report of activity determination of Paepalanthus spp. flavonoids activity against Mycobacterium tuberculosis and M. avium.