Beneficial interactions between plants and microorganisms have been investigated under different ecological, physiological, biochemical, and genetic aspects. However, the systematic exploration of biomolecules with potential for biotechnological products from this interaction still is relatively scarce. Therefore, this study aimed the evaluation of the diversity and antimicrobial activity of the endophytic fungi obtained from roots, stems and leafs of Myrcia guianensis (Myrtaceae) from the Brazilian Amazon. 156 endophytic fungi were isolated and above 80% were identified by morphological examination as belonging to the genera Pestalotiopsis, Phomopsis, Aspergillus, Xylaria, Nectria, Penicillium and Fusarium. Fermented broth of those fungi were assayed for antimicrobial activity and four inhibited the growth of Staphylococcus aureus, Enterococcus faecalis, Candida albicans and Penicillium avellaneum. As the strain named MgRe2.2.3B (Nectria haematococca) had shown the most promising results against those pathogenic strains, its fermented broth was fractioned and only its two low polar fractions demonstrated to be active. Both fractions exhibited a minimum bactericidal concentration of 50 μg.mL−1 against S. aureus and a minimum fungicidal concentration of 100 μg.mL−1 against P. avellaneum. These results demonstrate the diversity of fungal genera in M. guianensis and the potential of these endophytic fungi for the production of new antibiotics.

Introduction: Intestinal parasites are common in children in poor countries around the world, and are the cause of serious health problems. Objective: To evaluate the prevalence of intestinal parasites in schoolchildren in Santarém, and associated socio-environmental risk factors. Methods: Questionnaires were applied to parents, and fecal exams were performed by direct method and sedimentation. Results: The parasites that prevailed were Entamoeba coli (20.4%) and Ascaris lumbricoides (9.0%). The family income is an important factor related to parasitic infections (χ 2 =21.000/p=0.001). Other factors such as water treatment (χ 2 =20.15/p=0.002), health infrastructure (χ 2 =25.40/p=0.001), and hygiene practices such as hand washing (χ 2 =11.54/p=0.003) were statistically significant for the presence of intestinal parasites too, some on a lesser scale. Conclusion:The results showed that Entamoeba coli and Ascaris lumbricoides are the prevalent parasites. The family income, water quality, and sanitary infrastructure are the main risk factors for parasitic infections.

Aims To evaluate the production of biosurfactants by fungi isolated from the Amazonian species Piper hispidum (Piperaceae), and to determine the physico‐chemical properties of the crude biosurfactant obtained from the most promising fungi. Methods and Results A total of 117 endophytic fungi were isolated, and 50 were used to verify the production of biosurfactants. Of these, eight presented positive results in the drop collapse test, and emulsification index ranging from 20 to 78%. The most promising fungi, Ph III 23L and Ph II 22S (identified as Aspergillus niger and Glomerella cingulata, respectively) were recultivated for extraction and analysis of the biosurfactant’s physico‐chemical characteristics. The cultivation broth that presented the greatest decrease in surface tension (36%) was that of the A. niger, which reduced it from 68·0 to 44·0 mN m−1. The lowest critical micellar concentration value was found for the same endophyte (14·93 mg ml−1). Conclusions Endophytes of P. hispidum proved to be interesting producers of biosurfactants and presented promising physico‐chemical characteristics for applications in diverse industrial sectors. Significance and Impact of the Study Piper hispidum endophytic fungi can be used as a new source of biosurfactants, as these molecules present a significant market due to their wide industrial applications.

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