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The discovery of new metabolites potentially bioactive against pathogenic microorganisms, mainly multidrug resistant, has aroused interest in endophytic fungi. The plant-associated microorganisms have been an important source for development of new compounds of biotechnological interest. This study aimed to investigate the antibacterial capacity of the endophytic fungus, Phoma sp. URM 7221 isolated from the medicinal plant Schinus terebinthifolius against human-pathogenic bacteria. An endophyte was isolated from S. terebinthifolius leaves. Phoma herbarum URM7221 was characterized morphologically and on the basis of ITS rDNA sequence. Primary antimicrobial activity was evaluated using the agar diffusion method and fermentation in liquid medium. Six different solvents were used to extract the active metabolites from fungal biomass and metabolic liquid. An antimicrobial activity test from the extract was carried out using a disk diffusion method with the endophytic extract containing the best antibacterial activity. Two tests were performed: Minimum inhibitory concentration (MIC) and minimum bactericidal concentration (MBC). Partially purified secondary metabolite extracts were analysed by thin layer chromatography (TLC). Liquid metabolically bioactive compounds extracted with petroleum ether revealed a MIC of 25 and 500 μg.mL−1 against S. aureus and MRSA, respectively. Ether and methanol extracts were assessed by chemical analyses and contained phenolic compounds, triterpenes, steroids, reducing sugars, mono- and sesquiterpenes. The thin layer chromatography assay showed the activity of different antimicrobial compounds produced by Phoma sp. URM7221. This endophyte (URM7221) could be efficiently used for production of bioactive metabolites against pathogenic microorganisms, with significant biotechnological potential. Key words: Bioactive compounds, endophytic fungi, pathogenic bacteria, multidrug-resistance, antibacterial agents.

Endophytic fungi were isolated from leaves of the medicinal plant, Indigofera suffruticosa collected at the Atlantic Coastal Forest and tropical dry forest (Caatinga), Pernambuco, Brazil, during the dry and rainy seasons. A total of 107 fungal isolates, representing nine fungal taxa, were obtained and classified as Ascomycota, among them Colletotrichum gloeosporioides with relative frequency (fr) 27.1% and Pseudocochliobolus pallescens with fr 16.82% were the most frequent. Curvularia australiensis and Chaetomella raphigera were isolated only in Caatinga during rainy and dry seasons, respectively, and for the first time they were isolated from a Caatinga plant. Lasiodiplodia theobromae was found only in Atlantic Coastal Forest in dry season, and according to Simpson (D') and Shannon-Wiener (H') indices fungal diversity were considered statistically significant in this forest. Besides, a greater similarity was observed between fungi isolated in Atlantic Coastal Forest and Caatinga in the dry season, suggesting the predominance of seasonality rather than geographical factor. This study is the first report on endophytes fungi from I. suffruticosa, and the results represent an important basis for further studies in the fields of ecology and biotechnology, since these endophytic fungi may be important source for future study in searching for new natural compounds with biological activities. Key words: Ascomycota, Caatinga, endophytic mycobiota, fungal diversity, Indigofera suffruticosa, seasonal predominance.

The sugarcane borer, Diatraea saccharalis, is one of the worst pests in Brazilian sugarcane crop, causing high levels of financial losses every year. Beauveria bassiana is an entomopathogenic fungus widely used in the biological control of several agricultural pests. The aims of this study were to: (1) evaluate the pathogenicity of B. bassiana strains against D. saccharalis (2) investigate the production of proteases and chitinase by B. bassiana in the presence of the cuticle of sugarcane borer; and, (3) evaluate the relation between the production of enzymes and pathogenicity of the strains. All isolates tested were pathogenic to D. saccharalis and the mortality ranged from 36 to 88%. The production of enzymes was higher in the medium containing cuticle, showing that the process is stimulated by specific components found in the cuticle of the host. Pr1 activity was higher than Pr2 and both were produced at 24 h. The highest production of chitinase was obtained at 96 h of culture for all strains tested. Levels of specific cuticle-degrading enzymes such as proteases correlated positively with specific virulence parameters. B. bassiana URM2915 showed promising features to be used in a biological control program of D. saccharalis. Key words: Biological control, sugarcane, subtilisin-like protease, trypsin-like protease, chitinase.