National Biological Control Laboratory, Biological Control of Pests Research Unit, Agriculture Research Service, United States Department of Agriculture, 59 Lee Road, Stoneville, MS 38776, USA.
Biomolecules. 2020 May 5;10(5):716. doi: 10.3390/biom10050716.
Contact and fumigation toxicity of four isothiocyanates (ITCs), including allyl isothiocyanate (AITC), 3-butenyl isothiocyanate (3BITC), 3-(methylthio) propyl isothiocyanate (3MPITC) and 2-phenylethyl isothiocyanate (2PEITC), were evaluated against the red imported fire ant worker, Buren. 2PEITC and 3MPITC exhibited strong contact toxicity. The median lethal dose (LD)value of AITC, 2PEITC and 3MPITC were 7.99, 2.36 and 2.09 µg/ant respectively. In addition, AITC and 3MPITC also showed strong fumigation toxicity but not 2PEITC. The median lethal concentration (LC) values of AITC and 3MPITC were 32.49 and 57.6 µg/L, respectively. In contrast, 3BITC did not exhibit any contact and fumigation toxicity even at 100 μg/μL. Esterase (EST), glutathione -transferase (GST) and acetylcholinesterase (AChE)-inhibiting activities were assessed for three ITCs in workers. All three ITCs inhibited both EST and GST activities but not AChE. The in vitro half maximal inhibitory concentration (IC)values of AITC, 2PEITC and 3MPITC for GST were 3.32, 0.61 and 0.66 µg/µL, respectively. These results suggested that naturally occurring ITCs might be potentially useful for developing fire ants control products.
四种异硫氰酸酯(ITCs),包括丙烯基异硫氰酸酯(AITC)、3-丁烯基异硫氰酸酯(3BITC)、3-(甲基硫代)丙基异硫氰酸酯(3MPITC)和 2-苯乙基异硫氰酸酯(2PEITC)对红火蚁工蚁的接触和熏蒸毒性进行了评估。2PEITC 和 3MPITC 表现出很强的接触毒性。AITC、2PEITC 和 3MPITC 的半数致死剂量(LD)值分别为 7.99、2.36 和 2.09 µg/只。此外,AITC 和 3MPITC 还表现出很强的熏蒸毒性,但 2PEITC 则没有。AITC 和 3MPITC 的半数致死浓度(LC)值分别为 32.49 和 57.6 µg/L。相比之下,即使在 100 µg/µL 时,3BITC 也没有表现出任何接触和熏蒸毒性。在红火蚁工蚁中评估了三种 ITCs 对酯酶(EST)、谷胱甘肽-S-转移酶(GST)和乙酰胆碱酯酶(AChE)的抑制活性。三种 ITCs 均抑制 EST 和 GST 活性,但不抑制 AChE。AITC、2PEITC 和 3MPITC 对 GST 的体外半数最大抑制浓度(IC)值分别为 3.32、0.61 和 0.66 µg/µL。这些结果表明,天然存在的 ITCs 可能是开发红火蚁防治产品的潜在有用物质。