CBQF-Escola Superior de Biotecnologia, Universidade Católica Portuguesa Porto, Rua Dr. António Bernardino de Almeida, 4200-072 Porto, Portugal.
Centro de Investigação de Montanha (CIMO), ESA, Instituto Politécnico de Bragança, Campus de Santa Apolónia, Apartado 1172, 5301-855 Bragança, Portugal.
Pathogens. 2014 Aug 6;3(3):667-79. doi: 10.3390/pathogens3030667.
Microorganisms can colonize a wide variety of medical devices, putting patients in risk for local and systemic infectious complications, including local-site infections, catheter-related bloodstream infections, and endocarditis. These microorganisms are able to grow adhered to almost every surface, forming architecturally complex communities termed biofilms. The use of natural products has been extremely successful in the discovery of new medicine, and mushrooms could be a source of natural antimicrobials. The present study reports the capacity of wild mushroom extracts to inhibit in vitro biofilm formation by multi-resistant bacteria. Four Gram-negative bacteria biofilm producers (Escherichia coli, Proteus mirabilis, Pseudomonas aeruginosa, and Acinetobacter baumannii) isolated from urine were used to verify the activity of Russula delica, Fistulina hepatica, Mycena rosea, Leucopaxilus giganteus, and Lepista nuda extracts. The results obtained showed that all tested mushroom extracts presented some extent of inhibition of biofilm production. Pseudomonas aeruginosa was the microorganism with the highest capacity of biofilm production, being also the most susceptible to the extracts inhibition capacity (equal or higher than 50%). Among the five tested extracts against E. coli, Leucopaxillus giganteus (47.8%) and Mycenas rosea (44.8%) presented the highest inhibition of biofilm formation. The extracts exhibiting the highest inhibitory effect upon P. mirabilis biofilm formation were Sarcodon imbricatus (45.4%) and Russula delica (53.1%). Acinetobacter baumannii was the microorganism with the lowest susceptibility to mushroom extracts inhibitory effect on biofilm production (highest inhibition-almost 29%, by Russula delica extract). This is a pioneer study since, as far as we know, there are no reports on the inhibition of biofilm production by the studied mushroom extracts and in particular against multi-resistant clinical isolates; nevertheless, other studies are required to elucidate the mechanism of action.
微生物可以定植于各种医疗设备，使患者面临局部和全身感染性并发症的风险，包括局部部位感染、导管相关血流感染和心内膜炎。这些微生物能够附着在几乎所有表面生长，形成结构复杂的群落，称为生物膜。天然产物的使用在新药发现方面取得了巨大成功，而蘑菇可能是天然抗菌剂的来源。本研究报告了野生蘑菇提取物抑制多耐药菌体外生物膜形成的能力。从尿液中分离出的 4 种革兰氏阴性菌生物膜生产者（大肠杆菌、奇异变形杆菌、铜绿假单胞菌和鲍曼不动杆菌）用于验证红绒盖牛肝菌、红栓菌、玫红蘑菇、大青褶伞和白黄侧耳提取物的活性。结果表明，所有测试的蘑菇提取物在一定程度上抑制了生物膜的产生。铜绿假单胞菌是生物膜产生能力最高的微生物，也是最容易受到提取物抑制能力影响的微生物（等于或高于 50%）。在测试的 5 种针对大肠杆菌的提取物中，大青褶伞（47.8%）和玫红蘑菇（44.8%）对生物膜形成的抑制作用最强。对奇异变形杆菌生物膜形成抑制作用最强的提取物为皱盖钟菌（45.4%）和红绒盖牛肝菌（53.1%）。鲍曼不动杆菌对蘑菇提取物抑制生物膜形成的敏感性最低（红绒盖牛肝菌提取物的抑制率接近 29%）。这是一项开创性的研究，因为据我们所知，目前还没有关于研究中蘑菇提取物抑制生物膜形成的报道，特别是针对多耐药临床分离株；然而，需要进一步的研究来阐明其作用机制。
