Baglyas Márton, Bozsó Zoltán, Schwarczinger Ildikó, Ott Péter G, Bakonyi József, Darcsi András, Móricz Ágnes M
Plant Protection Institute, HUN-REN Centre for Agricultural Research, Fehérvári út 132-144, 1116 Budapest, Hungary; Doctoral School, Semmelweis University, Üllői út 26, 1085 Budapest, Hungary.
Plant Protection Institute, HUN-REN Centre for Agricultural Research, Fehérvári út 132-144, 1116 Budapest, Hungary.
Phytochemistry. 2026 Jan;241:114674. doi: 10.1016/j.phytochem.2025.114674. Epub 2025 Sep 8.
The demand for previously undescribed antimicrobial agents is increasing due to the emergence of resistant plant pathogens. One of the untapped sources of new biopesticides is the plant kingdom. A bioassay-guided process comprising TLC-Bacillus subtilis bioassay, TLC-MS, and preparative flash column chromatography enabled the isolation of five previously undescribed antimicrobial labdane diterpenes (graminifolins A-E, 1-5) from the flower extract of grass-leaved goldenrod (Euthamia graminifolia, formerly known as Solidago graminifolia). Their structures were elucidated by NMR spectroscopy, supported by HRMS/MS, polarimetry, and UV, and ATR-FTIR spectroscopy. Graminifolins A-C (1-3) displayed low to moderate antibacterial and bactericidal activity against the Gram-positive plant pathogens Curtobacterium flaccumfaciens pv. flaccumfaciens and Clavibacter michiganensis, with MIC values between 67 and 533 μg/mL and MBC values ranging from 133 to 533 μg/mL. In contrast, graminifolin D+E (4+5) was active only against C. michiganensis. Among the isolated compounds, graminifolin A exhibited the strongest antibacterial effect and demonstrated weak antifungal activity against the crop pathogen Bipolaris sorokiniana. These findings underscore the potential of bioassay-guided fractionation in discovering previously undescribed bioactive compounds.
由于耐药植物病原体的出现，对以前未描述过的抗菌剂的需求正在增加。植物界是新生物农药未开发的来源之一。一个由薄层色谱-枯草芽孢杆菌生物测定、薄层色谱-质谱和制备型快速柱色谱组成的生物测定引导过程，使得从柳叶泽兰（Euthamia graminifolia，以前称为Solidago graminifolia）的花提取物中分离出了五种以前未描述过的抗菌半日花烷二萜（禾叶泽兰素A-E，1-5）。它们的结构通过核磁共振光谱进行了阐明，并得到了高分辨质谱/质谱、旋光测定、紫外光谱和衰减全反射傅里叶变换红外光谱的支持。禾叶泽兰素A-C（1-3）对革兰氏阳性植物病原体萎蔫短小杆菌（Curtobacterium flaccumfaciens pv. flaccumfaciens）和密歇根棒状杆菌（Clavibacter michiganensis）表现出低到中等的抗菌和杀菌活性，最低抑菌浓度值在67至533μg/mL之间，最低杀菌浓度值在133至533μg/mL之间。相比之下，禾叶泽兰素D+E（4+5）仅对密歇根棒状杆菌有活性。在分离出的化合物中，禾叶泽兰素A表现出最强的抗菌作用，并对作物病原体小麦根腐离蠕孢（Bipolaris sorokiniana）表现出弱的抗真菌活性。这些发现强调了生物测定引导分级分离在发现以前未描述过的生物活性化合物方面的潜力。
