Laboratório de Farmacognosia, Faculdade de Farmácia, Universidade Federal do Rio Grande do Sul, Av. Ipiranga, 2752, CEP 90.610-000 Porto Alegre, RS, Brazil.
Laboratório de Micologia Aplicada, Faculdade de Farmácia, Universidade Federal do Rio Grande do Sul, Porto Alegre, Brazil.
J Mycol Med. 2017 Dec;27(4):530-538. doi: 10.1016/j.mycmed.2017.07.006. Epub 2017 Aug 16.
Intensive prophylactic use of antifungals leads to the increase of drug resistance and the need for new and more effective treatments are real. Plants from Leguminosae family are rich in flavonoids, for which numerous biological activities have been described, including antifungal effects.
To screen methanolic extracts from Leguminosae species looking for alternative sources for antifungal agents (anti-dermatophyte and anti-Candida) and their innocuity.
Antifungal activity was evaluated using the strains Candida albicans, C. krusei, C. glabrata, C. tropicalis, C. parapsilosis, Epidermophyton floccosum, Trichophyton mentagrophytes, T. rubrum and, Microsporum gypseum in the broth microdilution method. Later, the minimum inhibitory concentration (MIC) for Mimosa pigra, Eriosema heterophyllum, and Chamaecrista nictitans was determined. The most promising extract was fractionated and cytotoxicity and genotoxicity of the most active fraction were also assayed.
Fungicide and/or fungistatic activity against dermatophyte strains were presented by 60% of the methanolic extracts assayed. M. pigra, E. heterophyllum, and C. nictitans methanolic extracts could inhibit dermatophyte strains at concentrations ranging from 1.9 to 1000μg/mL. M. pigra showed the lowest MIC values for a dichloromethane fraction (1.9μg/mL) without DNA damage at 10 and 50μg/mL and 100% of cell viability of human leukocytes.
Our results indicate that methanolic extracts from Leguminosae plants are potential sources of antifungal compounds, mainly the extract and fractions from M. pigra. The dichloromethane fraction from M. pigra did not showed in vitro toxicity according to the applied assays.
强化预防性使用抗真菌药物会导致耐药性增加，因此确实需要新的、更有效的治疗方法。豆科植物富含类黄酮，具有多种生物活性，包括抗真菌作用。
筛选豆科植物的甲醇提取物，寻找抗真菌药物（抗皮肤真菌和抗念珠菌）的替代来源及其无害性。
采用肉汤微量稀释法评估抗真菌活性，检测菌株包括白色念珠菌、克柔念珠菌、光滑念珠菌、热带念珠菌、近平滑念珠菌、絮状表皮癣菌、须癣毛癣菌、红色毛癣菌和石膏样小孢子菌。然后，确定小冠含羞草、异叶山蚂蝗和光叶决明的最小抑菌浓度（MIC）。对最有前景的提取物进行分级，并测定最活跃级分的细胞毒性和遗传毒性。
所检测的 60%甲醇提取物对皮肤真菌菌株具有杀菌和/或抑菌活性。小冠含羞草、异叶山蚂蝗和光叶决明的甲醇提取物可在 1.9 至 1000μg/ml 的浓度范围内抑制皮肤真菌菌株。小冠含羞草的二氯甲烷级分（MIC 值为 1.9μg/ml）在 10 和 50μg/ml 时无 DNA 损伤，对人白细胞的细胞活力为 100%，显示出最低的 MIC 值。
我们的研究结果表明，豆科植物的甲醇提取物是抗真菌化合物的潜在来源，特别是小冠含羞草的提取物和级分。根据应用的测定方法，小冠含羞草的二氯甲烷级分在体外没有显示出毒性。
