Bioprospecção de antibióticos produzidos por fungos da caatinga.

Abstract

The emergence of super-resistant microorganisms induces the pharmaceutical industry to develop new antibiotics, broad spectrum drugs with most effectiveness against bacteria and other pathogens are being developed. Therefore, this study aimed to use filamentous fungi Paraíba´s Caatinga collected for antibiotics production, since the need for research in this direction using Caatinga´s fungi, opening expectation of pharmaceutical industry´s innovation. The fungi were collected and evaluated for their potential to produce antimicrobial compounds against Gram-negative (Escherichia coli) and Gram positive (Staphylococcus aureus) bacteria. Among the seventy two isolates, fifty seven (79.17%) showed some antimicrobial activity, of which twenty seven (47.37%) have activity against both bacteria and thirty (52.63%) with activity against only one of these. In line for to better results demonstrated in antibiotic susceptibility testing, the CDSA30 and CDSA71 isolates were selected for purification of antibacterial extracts, by RP-HPLC. In the purification extracts, were found two antimicrobial substances with antimicrobial activity, against both bacterial strains used. These fungi were identified as belonging to the genus Aspergillus. The study of the effect of temperature, on the antibiotics production, indicated that there is increased yield in the metabolites production, with antimicrobial activity, when the temperature´s cultivation is 45°C.