Paventi Gianluca, Rotundo Giuseppe, Pistillo Marco, D'Isita Ilaria, Germinara Giacinto Salvatore
Department of Medicine and Health Sciences "V. Tiberio", University of Molise, via de Sanctis, 86100 Campobasso, Italy.
Department of Agricultural, Environmental and Food Sciences, University of Molise, via de Sanctis, 86100 Campobasso, Italy.
Insects. 2021 Jun 19;12(6):564. doi: 10.3390/insects12060564.
The use of bioinsecticides, rather than synthetic compounds, appears a goal to be pursued in pest control, especially for species such as (L.) which attack stored products. Since (L.) is a remarkable source of bioactive compounds, this study investigated the bioactivity of hop flower extracts against adults by evaluating toxic (contact, inhalation, and ingestion), repellent, antifeedant, and nutritional effects as well as their anticholinesterase activity and olfactory sensitivity. Hop extracts were obtained by soaking dried and ground hop cones in solvents of decreasing polarity: methanol, acetone, and -hexane. Dried crude extracts were resuspended in each solvent, and used in topical application, ingestion, and fumigation toxicity assays, as well as in contact and short-range repellency tests, in vitro anticholinesterase activity evaluation, and electroantennographic tests. No inhalation toxicity for the extracts was found. On the contrary, all extracts showed adult contact toxicity 24 h after treatment (LDLD 16.17/33.20, 25.77/42.64, and 31.07/49.48 µg/adult for acetone, -hexane, and methanol extracts, respectively); negligible variations for these values at 48 h were found. The anticholinesterase activity shown by all extracts suggested that the inhibition of this enzyme was one of the mechanisms of action. Interestingly, flour disk bioassays revealed a significant ingestion toxicity for the acetone extract and a lower toxicity for the other two extracts. Moreover, all extracts affected insect nutritional parameters, at the highest dose checked. Filter paper and two-choice pitfall bioassays showed repellent activity and a strong reduction of insect orientation to a highly attractive food odor source, with minor differences among extracts, respectively. Finally, the presence of volatile compounds in the different extracts that are perceived by insect antennae was confirmed by electroantennography. All these findings strongly suggest a possible use of hop cone extracts against , thus further confirming this plant as an interesting species for pest control.
使用生物杀虫剂而非合成化合物似乎是害虫防治中一个值得追求的目标，尤其是对于攻击储存产品的物种，如（此处原文缺失具体物种名）（L.）。由于（此处原文缺失具体物种名）（L.）是生物活性化合物的重要来源，本研究通过评估毒性（接触、吸入和摄入）、驱避、拒食和营养作用以及它们的抗胆碱酯酶活性和嗅觉敏感性，研究了啤酒花提取物对（此处原文缺失具体物种名）成虫的生物活性。通过将干燥研磨的啤酒花球果浸泡在极性递减的溶剂中获得啤酒花提取物：甲醇、丙酮和正己烷。将干燥的粗提物重新悬浮在每种溶剂中，并用于局部应用、摄入和熏蒸毒性试验，以及接触和短程驱避试验、体外抗胆碱酯酶活性评估和触角电位测试。未发现提取物有吸入毒性。相反，所有提取物在处理后24小时均显示出成虫接触毒性（丙酮、正己烷和甲醇提取物的致死剂量分别为16.17/33.20、25.77/42.64和31.07/49.48微克/成虫）；48小时时这些值的变化可忽略不计。所有提取物显示的抗胆碱酯酶活性表明该酶的抑制是作用机制之一。有趣的是，面粉圆盘生物测定显示丙酮提取物有显著的摄入毒性，而其他两种提取物的毒性较低。此外，在检查的最高剂量下，所有提取物都影响昆虫的营养参数。滤纸和双选陷阱生物测定分别显示出驱避活性以及昆虫对极具吸引力的食物气味源的定向能力大幅降低，提取物之间差异较小。最后，通过触角电位图证实了不同提取物中存在能被昆虫触角感知的挥发性化合物。所有这些发现强烈表明啤酒花球果提取物可能用于防治（此处原文缺失具体物种名），从而进一步证实这种植物是害虫防治的一个有价值的物种。
