Agricultural Research Service, Natural Products Utilization Research Unit, U.S. Department of Agriculture, University, MS 38677, USA.
National Center for Natural Products Research, University, MS 38677, USA.
Molecules. 2023 Dec 4;28(23):7930. doi: 10.3390/molecules28237930.
The identification of natural and environmentally friendly pesticides is a key area of interest for the agrochemical industry, with many potentially active compounds being sourced from numerous plant species. In this study, we report the bioassay-guided isolation and identification of phytotoxic and antifungal compounds from the ethyl acetate extract of stems. We identified eight compounds, consisting of two coumarins and six alkaloids. Among these, a new alkaloid, 2-hydroxy-3,6,7-trimethoxyquinoline-4-carbaldehyde (), was elucidated, along with seven known compounds. The phytotoxicity of purified compounds was evaluated, and chalepin () was active against at 1 mM with 50% inhibition of seed germination and it reduced (duckweed) growth by 50% (IC) at 168 μM. Additionally, we evaluated the antifungal activity against the fungal plant pathogen using a thin-layer chromatography bioautography assay, which revealed that three isolated furoquinoline alkaloids (flindersiamine (), kokusagenine (), and maculine ()) among the isolated compounds had the strongest inhibitory effects on the growth of at all tested concentrations. Our results indicate that these active natural compounds, i.e., (), (), (), and (), could be scaffolds for the production of more active pesticides with better physicochemical properties.
天然和环保农药的鉴定是农用化学品行业关注的一个关键领域,许多潜在的活性化合物都来自于许多植物物种。在这项研究中,我们报告了从茎的乙酸乙酯提取物中通过生物测定指导分离和鉴定具有植物毒性和抗真菌化合物的情况。我们鉴定出了八种化合物,包括两种香豆素和六种生物碱。其中,阐明了一种新的生物碱,2-羟基-3,6,7-三甲氧基喹啉-4-甲醛(),以及七种已知化合物。纯化化合物的植物毒性进行了评估,chalepin()在 1mM 时对 表现出活性,种子发芽抑制率为 50%,在 168μM 时对 (浮萍)的生长抑制率为 50%(IC)。此外,我们使用薄层色谱生物自显影测定法评估了对真菌植物病原体 的抗真菌活性,结果表明,在所测试的所有浓度下,分离出的化合物中三种分离出的呋喃喹啉生物碱(flindersiamine()、kokusagenine()和 maculine())对 的生长具有最强的抑制作用。我们的研究结果表明,这些具有生物活性的天然化合物,即()、()、()和(),可能是具有更好理化性质的更具活性农药的生产的支架。