Endophytic fungi from Myrcia guianensis at the Brazilian Amazon: distribution and bioactivity

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.

The Anti-cancer Effects in Vivo of Fungus Plant Extract on Transplanted Tumor S-180 in Mice and the Synergistic Effects with Cyclophosphamide / 昆明医科大学学报

Objective Study the anti-tumor effects in vivo of AMH-D on S-180 cell lines, the synergistic effects of AMH-D and cyclophosphamide,and investigate the way and its strength of the effect. Provide the basis for the development of anti-cancer drug. Methods Kunming mice were transplanted with S-180 tumor cells subcutaneously in the right armpit. Intraperitoneal injection was done after randomization on the next day. Mice were killed on the eleventh day, and tumors were stripped and weighed. The tumor weight was used as indicator for analysis and evaluation. Results The results showed that AMH-D could effectively inhibit the growth of S180 cells transplanted tumor. The tumor inhibition rate was 50.45%at the dose of 150 mg/kg, with a dose-effect relationship. There were no obvious impacts on the growth of the weight of mice. The results showed that AMH-D had a synergistic effect combined with cyclophosphamide within a certain dose. Conclusion Fungus extract AMH-D has a great effect on anti-tumor in vivo of S180 cells transplanted tumor, and has a synergistic effect combined with cyclophosphamide within a certain dose.