Análise da composição das cinzas do bagaço do pedúnculo do cajú (Anacardium occidentale L.) e sua atividade antifúngica in vitro contra espécies de Fusarium

Abstract

Cashew (Anacardium occidentale L.) is a plant with a highly social and economic importance in Northeast Brazil. Cashew peduncle bagasse is one of the greatest sources of residues (90–94%) produced by the cashew agronomic industry. In this study, we prepared cashew peduncle bagasse ashes and submitted them to compositional analysis and tests for antifungal activity in vitro against Fusarium species. This analysis indicated a crystallinity around 73%, corresponding to the following soluble phases: acid potassium carbonate- KHCO3 (39.54%), potassium sulfate - K2SO4 (24.87%), and struvite-K - MgKPO4·6H2O (8.59%). The amorphous phases (around 27%) were identified as the insoluble fraction of ashes. The solution showed high antifungal activity against F. oxysporum, F. moniliforme and F. lateritium. This activity of this product was greater than that of Cercobin® (thiophanate-methyl), indicating a possible use of this material as a non-toxic antifungal agent.