Department of Chemical Sciences, University of Naples Federico II, Complesso Universitario Monte S. Angelo, Via Cintia 4, 80126 Naples, Italy.
Department of Biology, University of Naples Federico II, Complesso Universitario Monte Sant'Angelo, Via Cintia 4, 80126 Naples, Italy.
Toxins (Basel). 2022 Aug 17;14(8):559. doi: 10.3390/toxins14080559.
is an obligate holoparasitic plant with noxious effects in sunflower crops. is a facultative hemiparasitic plant that infects ruderal plants without noxious significance in agriculture and is known to produce a wide spectrum of bioactive metabolites. The objective of this study was to evaluate the allelopathic effects of on the growth of seedlings. Three different extracts using solvents of increasing polarity (-hexane, dichloromethane and ethyl acetate) were prepared from the flowers, aerial green organs and roots of two populations, a white-flowered and a yellow-flowered population of , both collected in southern Spain. Each extract was studied using allelopathic screenings on which resulted in the identification of allelopathic activity of the ethyl acetate extracts against radicles. Five iridoid glycosides were isolated together with benzoic acid from the ethyl acetate extract of aerial green organs by bio-guided purification. These compounds were identified as bartsioside, melampyroside, mussaenoside, gardoside methyl ester and aucubin. Among them, melampyroside was found to be the most abundant constituent in the extract (44.3% /), as well as the most phytotoxic iridoid on radicle, showing a 72.6% inhibition of radicle growth. This activity of melampyroside was significantly high when compared with the inhibitory activity of benzoic acid (25.9%), a phenolic acid with known allelopathic activity against weeds. The ecotoxicological profile of melampyroside was evaluated using organisms representing different trophic levels of the aquatic and terrestrial ecosystems, namely producers (green freshwater algae and macrophyte ), consumers (water flea and nematode ) and decomposers (bacterium ). The ecotoxicity of melampyroside differed significantly depending on the test organism showing the highest toxicity to daphnia, nematodes and bacteria, and a lower toxicity to algae and macrophytes. The findings of the present study may provide useful information for the generation of green alternatives to synthetic herbicides for the control of .
是一种专性全寄生植物，对向日葵作物有有害影响。是一种兼性半寄生植物，感染野生植物，在农业中没有有害意义，已知能产生广泛的生物活性代谢物。本研究的目的是评估对 幼苗生长的化感作用。从两种种群的花、气生绿色器官和根中用极性递增的溶剂（正己烷、二氯甲烷和乙酸乙酯）制备了三种不同的提取物，这两种种群是在西班牙南部采集的白色花和黄色花种群。用化感筛选法对 进行了研究，结果表明，来自气生绿色器官的乙酸乙酯提取物对 根具有化感活性。通过生物导向纯化，从气生绿色器官的乙酸乙酯提取物中分离出 5 种裂环环烯醚萜糖苷和苯甲酸。这些化合物被鉴定为 bartsioside、melampyroside、mussaenoside、gardoside methyl ester 和 aucubin。其中，melampyroside 被发现是提取物中最丰富的成分（44.3%/），也是对 根最具植物毒性的裂环环烯醚萜，对 根生长的抑制率达到 72.6%。与具有已知除草化感活性的苯甲酸（25.9%）相比，melampyroside 的这种活性显著较高。采用代表水生和陆地生态系统不同营养级的生物评估了 melampyroside 的生态毒性，即生产者（绿色淡水藻类和大型藻类）、消费者（水蚤和线虫）和分解者（细菌）。melampyroside 的生态毒性因测试生物而异，对水蚤、线虫和细菌的毒性最高，对藻类和大型藻类的毒性较低。本研究的结果可为开发控制 的绿色替代合成除草剂提供有用信息。
