School of Science, Mae Fah Luang University, Chiang Rai, 57100, Thailand.
Center of Chemical Innovation for Sustainability (CIS), Mae Fah Luang University, Chiang Rai, 57100, Thailand.
Curr Microbiol. 2018 Apr;75(4):476-483. doi: 10.1007/s00284-017-1405-9. Epub 2017 Nov 20.
Fifty-two strains of endophytic fungi were isolated from flowers of the medicinal plant Melodorum fruticosum. Seven genera were identified including Alternaria, Aspergillus, Colletotrichum, Diaporthe, Fusarium, Greeneria and Nigrospora. All strains were cultured for 30 days and further macerated in ethyl acetate solvent for 3 days. The obtained fungal extracts were examined for antibacterial activity using agar disc diffusion against nine pathogenic bacteria: Staphylococcus aureus, Bacillus subtilis, B. cereus, Klebsiella pneumoniae, Pseudomonas aeruginosa, Escherichia coli, Shigella flexneri, Vibrio cholerae and V. parahaemolyticus. Forty-three fungal extracts exhibited antibacterial activity against at least one tested pathogen. The antioxidant properties of all extracts were also investigated by DPPH scavenging assay. Sixteen extracts displayed high antioxidant capacity (IC ranging from 10 to 50 µg/mL) when compared to the gallic acid and trolox standards (IC of 12.46 and 2.55 µg/mL, respectively). The crude extracts of Diaporthe sp. MFLUCC16-0682 and Diaporthe sp. MFLUCC16-0693 exhibited notable antibacterial and antioxidant activities. Analysis of chemical composition using gas chromatography-mass spectrometry suggested that the observed antibacterial activity of the two Diaporthe spp. was possibly due to the presence of abienol, 4-methoxy stilbene, phenethyl cinnamate and 2Z,6Z-farnesal, while their potential antioxidant activity could be attributed to phenolic compounds, such as benzene acetaldehyde, benzyl benzoate, salicylaldehyde, benzoin and benzyl cinnamate. The results suggest that the genus Diaporthe is a potential source of metabolites that can be used in a variety of applications.
从药用植物苦荬菜花朵中分离得到 52 株内生真菌。鉴定出 7 个属，包括链格孢属、曲霉属、炭疽菌属、间座壳属、镰刀菌属、Greeneria 和黑孢霉属。所有菌株均培养 30 天，然后用乙酸乙酯溶剂进一步浸提 3 天。用琼脂平板扩散法对 9 种致病菌（金黄色葡萄球菌、枯草芽孢杆菌、蜡样芽孢杆菌、肺炎克雷伯菌、铜绿假单胞菌、大肠杆菌、福氏志贺菌、霍乱弧菌和副溶血弧菌）进行抗菌活性检测，共检测到 43 株真菌提取物对至少一种测试病原体具有抗菌活性。还通过 DPPH 清除试验研究了所有提取物的抗氧化性能。与没食子酸和 Trolox 标准品（IC 分别为 12.46 和 2.55μg/mL）相比，16 种提取物具有较高的抗氧化能力（IC 范围为 10-50μg/mL）。Diaporthe sp. MFLUCC16-0682 和 Diaporthe sp. MFLUCC16-0693 的粗提物表现出显著的抗菌和抗氧化活性。使用气相色谱-质谱联用分析化学成分表明，两种间座壳属真菌表现出的抗菌活性可能是由于存在 abienol、4-甲氧基二苯乙烯、肉桂酸苯乙酯和 2Z,6Z-法呢醛，而它们潜在的抗氧化活性可能归因于酚类化合物，如苯乙醛、苯甲酸苄酯、水杨醛、安息香和肉桂酸苄酯。研究结果表明，间座壳属是一种具有多种应用潜力的代谢产物的潜在来源。
