Medicinal Plants Used by a Mbyá-Guarani Tribe Against Infections: Activity on KPC-Producing Isolates and Biofilm-Forming Bacteria
Abstract
The traditional use of medicinal plants for treatment of infectious diseases by an indigenous Mbyá-Guarani tribe from South Brazil
was assessed by evaluating the antibiotic and antibiofilm activities
against relevant bacterial pathogens. Aqueous extracts from 10 medicinal plants
were prepared according to indigenous Mbyá-Guarani traditional uses. To
evaluate antibiotic (OD600) and antibiofilm (crystal violet method)
activities, Pseudomonas aeruginosa ATCC 27853, Staphylococcus
epidermidis ATCC 35984 and seven multi-drug resistant Klebsiella
pneumoniae carbapenemase (KPC)-producing bacterial clinical isolates
were challenged with the extracts. Furthermore, the susceptibility
profile of KPC-producing bacteria and the ability of these isolates to
form biofilm were evaluated. The plants
Campomanesia xanthocarpa, Maytenus ilicifolia, Bidens pilosa and
Verbena sp. showed the best activity against bacterial growth and
biofilm formation. The majority of KPC-producing isolates, which showed
strong ability to form biofilm and a multidrug resistance profile, was
inhibited by more than 50% by some extracts. The Enterobacter cloacae
(KPC 05) clinical isolate was the only one resistant to all extracts.
This study confirms the importance of indigenous traditional medicinal knowledge and describes for the first time the ability of these plants to inhibit biofilm formation and/or bacterial growth of multi-drug resistant KPC-producing isolates.
