Jorcin Gabriela, Barneche Stephanie, Vázquez Alvaro, Cerdeiras María Pía, Alborés Silvana
Laboratorio de Microbiologia, Departamento de Biociencias, Facultad de Quimica, Universidad de la República, Montevideo, Uruguay.
Laboratorio de Farmacognosia, Departamento de Quimica Organica, Facultad de Quimica, Universidad de la Republica, Montevideo, Uruguay.
Int J Med Mushrooms. 2017;19(8):737-744. doi: 10.1615/IntJMedMushrooms.2017021217.
Among many sources of natural bioactive substances, mushrooms constitute a huge and mostly unexplored group. Biologically active secondary metabolites of Ganoderma, a group of wood-degrading mushrooms, have recently been reviewed. Our previous study revealed the antimicrobial activity of extracts from G. resinaceum grown in submerged culture against phytopathogens. Different factors can influence the production of secondary metabolites, including nutritional factors. In this study we evaluated the influence of different culture conditions on the antimicrobial activity of extracts from liquid cultures of G. resinaceum, through use of a factorial design. Minimum inhibitory concentrations for extracts produced under different culture conditions were determined against Staphylococcus aureus and Xanthomonas vesicatoria. Based on the results of these assays, larger-scale cultures in malt extract broth supplemented with 20 g/L glucose and a 15-day incubation time should be performed in order to isolate from G. resinaceum antibiotic compound(s) that are potentially useful against S. aureus. In addition, pH 5 should be considered for the production of antimicrobial metabolites against X. vesicatoria from supernatant broths or extracts from G. resinaceum.
在众多天然生物活性物质来源中，蘑菇是一个庞大且大多未被探索的群体。灵芝属一类木腐菌，其生物活性次生代谢产物最近已有综述。我们之前的研究揭示了深层培养的树脂状灵芝提取物对植物病原体的抗菌活性。不同因素会影响次生代谢产物的产生，包括营养因素。在本研究中，我们通过析因设计评估了不同培养条件对树脂状灵芝液体培养提取物抗菌活性的影响。测定了在不同培养条件下产生的提取物对金黄色葡萄球菌和番茄疮痂病菌的最低抑菌浓度。基于这些测定结果，为了从树脂状灵芝中分离出对金黄色葡萄球菌可能有用的抗生素化合物，应在添加20 g/L葡萄糖的麦芽提取物肉汤中进行大规模培养，并培养15天。此外，从树脂状灵芝的上清液肉汤或提取物中生产针对番茄疮痂病菌的抗菌代谢产物时，应考虑pH值为5。
