Citrus black spot (CBS) and post-bloom fruit drop (PFD), caused by Phyllosticta citricarpa and Colletotrichum abscissum, respectively, are two important citrus diseases worldwide. CBS depreciates the market value and prevents exportation of citrus fruits to Europe. PFD under favorable climatic conditions can cause the abscission of flowers, thereby reducing citrus production by 80%. An ecofriendly alternative to control plant diseases is the use of endophytic microorganisms, or secondary metabolites produced by them. Strain LGMF1631, close related to Diaporthe cf. heveae 1, was isolated from the medicinal plant Stryphnodendron adstringens and showed significant antimicrobial activity, in a previous study. In view of the potential presented by strain LGMF1631, and the absence of chemical data for secondary metabolites produced by D. cf. heveae, we decided to characterize the compounds produced by strain LGMF1631. Based on ITS, TEF1, and TUB phylogenetic analysis, strain LGMF1631 was confirmed to belong to D. cf. heveae 1. Chemical assessment of the fungal strain LGMF1631 revealed one new seco-dihydroisocoumarin [cladosporin B (1)] along with six other related, already known dihydroisocoumarin derivatives and one monoterpene [(-)-(1S,2R,3S,4R)-p-menthane-1,2,3-triol (8)]. Among the isolated metabolites, compound 5 drastically reduced the growth of both phytopathogens in vitro and completely inhibited the development of CBS and PFD in citrus fruits and flowers. In addition, compound 5 did not show toxicity against human cancer cell lines or citrus leaves, at concentrations higher than used for the inhibition of the phytopathogens, suggesting the potential use of (-)-(3R,4R)-cis-4-hydroxy-5-methylmellein (5) to control citrus diseases.

中文翻译：

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Diaporthe生产的二氢异香豆素参见。heveae LGMF1631抑制柑橘病原体。

柑橘黑斑病（Phyllosticta citricarpa）和脱落酸炭疽菌（Colletotrichum abcisssum）分别引起的柑橘黑斑病（CBS）和开花后果实掉落（PFD）是全世界两种重要的柑橘病。CBS贬值了市场价值，并阻止了柑橘类水果向欧洲的出口。PFD在有利的气候条件下会导致花朵脱落，从而使柑橘产量降低80％。控制植物病害的一种环保替代方法是使用内生微生物或微生物产生的次级代谢产物。菌株LGMF1631，与Diaporthe cf相关。在先前的研究中，从药用植物Stryphnodendron adstringens中分离出三叶草1，并显示出显着的抗菌活性。考虑到菌株LGMF1631的潜力，以及缺乏D.产生的次级代谢产物的化学数据。橡胶树 我们决定表征菌株LGMF1631产生的化合物。根据ITS，TEF1和TUB的系统发育分析，确认菌株LGMF1631属于D. cf.。橡胶树1。对真菌菌株LGMF1631的化学评估显示了一种新的seco-dihydroisocoumarin [cladosporin B（1）]以及其他六种相关的已知二氢异香豆素衍生物和一种单萜[（-）-（1S，2R，3S，4R） -对-薄荷烷1,2,3-三醇（8）]。在分离出的代谢产物中，化合物5在体外显着降低了两种植物病原体的生长，并完全抑制了柑橘类水果和鲜花中CBS和PFD的发育。此外，化合物5对人癌细胞系或柑桔叶没有毒性，其浓度高于抑制植物病原体的浓度，表明（-）-（3R，