Departamento de Farmácia, Universidade Estadual de Maringá, Av. Colombo s/n(o), Maringá, PR, Brazil.
Exp Parasitol. 2011 Oct;129(2):175-8. doi: 10.1016/j.exppara.2011.06.011. Epub 2011 Jul 5.
Tetradenia riparia (Lamiaceae) is a well-known herbal medicine with a variety of useful properties, including its acaricidal effect. This experiment was carried out to study the bioacaricidal activity of T. riparia essential oil (EO) against engorged females of Rhipicephalus (Boophilus) microplus (Acari; Ixodidae). For this purpose, nine serial concentrations (12.50%, 6.25%, 3.75%, 1.80%, 0.90%, 0.45%, 0.22%, 0.11%, and 0.056% w/v) of T. riparia were used for the adult immersion test (AIT). For the larval packet test (LPT), we used 14 serial concentrations (100.00%, 50.00%, 25.00%, 12.50%, 6.25%, 3.65%, 1.82%, 0.91%, 0.45%, 0.228%, 0.114%, 0.057%, 0.028%, and 0.014% w/v). The results for AIT showed 100.00% and 2.05% mortality, 19.00 and 90.20% for the total number of eggs, egg-laying inhibition of 0.00% and 90.20%, hatchability inhibition of 0.00% and 70.23%, and product effectiveness of 100.00% and 2.89%, respectively. The AIT indicated that the LC(50) and LC(99.9), calculated using the Probit test, were for mortality (%) 0.534g/mL (0.436-0.632) and 1.552g/mL (1.183-1.92); for total number of eggs were 0.449g/mL (0.339-0.558) and 1.76g/mL (1.27-2.248); and for hatchability inhibition were 0.114g/mL (0.0-0.31) and 2.462g/mL (1.501-3.422), respectively. Larvae between 14 and 21days old were fasted and placed in each envelope. Bioassays were performed at 27°±1°C, RH⩾80%. Larval mortality was observed 24h after treatment and showed 10.60-100% mortality in the LPT bioassay. The LPT showed that the LC(50) and LC(99.9) were 1.222g/mL (0.655-1.788) and 11.382g/mL (7.84-14.91), respectively. A positive correlation between T. riparia EO concentration and tick control, was observed by the strong acaricidal effects against R. (B.) microplus, and the mortality rate of ticks was dose-dependent. Our results showed that T. riparia is a promising candidate as an acaricide against resistant strains of R. (B.) microplus.
拉帕里四棱草（唇形科）是一种具有多种有益特性的知名草药，包括其杀螨效果。本实验旨在研究拉帕里四棱草精油（EO）对饱血雌性璃眼蜱（牛蜱属）的生物杀螨活性。为此，我们使用了九种连续浓度（12.50%、6.25%、3.75%、1.80%、0.90%、0.45%、0.22%、0.11%和 0.056%w/v）的拉帕里四棱草进行成虫浸浴试验（AIT）。对于幼虫包囊试验（LPT），我们使用了 14 种连续浓度（100.00%、50.00%、25.00%、12.50%、6.25%、3.65%、1.82%、0.91%、0.45%、0.228%、0.114%、0.057%、0.028%和 0.014%w/v）。AIT 结果显示，死亡率为 100.00%和 2.05%，总产卵数为 19.00%和 90.20%，产卵抑制率为 0.00%和 90.20%，孵化抑制率为 0.00%和 70.23%，产品有效性为 100.00%和 2.89%。AIT 表明，死亡率（%）的 LC（50）和 LC（99.9）分别使用概率单位检验计算为 0.534g/mL（0.436-0.632）和 1.552g/mL（1.183-1.92）；总产卵数的 LC（50）和 LC（99.9）分别为 0.449g/mL（0.339-0.558）和 1.76g/mL（1.27-2.248）；孵化抑制率的 LC（50）和 LC（99.9）分别为 0.114g/mL（0.0-0.31）和 2.462g/mL（1.501-3.422）。14 至 21 日龄的幼虫禁食并放入每个信封中。在 27°C±1°C、相对湿度⩾80%的条件下进行生物测定。处理后 24 小时观察幼虫死亡率，并在 LPT 生物测定中显示 10.60-100%的死亡率。LPT 表明 LC（50）和 LC（99.9）分别为 1.222g/mL（0.655-1.788）和 11.382g/mL（7.84-14.91）。拉帕里四棱草 EO 浓度与蜱虫控制之间呈正相关，对耐蜱璃眼蜱具有强烈的杀螨作用，且死亡率呈剂量依赖性。我们的结果表明，拉帕里四棱草是一种很有前途的杀蜱候选药物，可用于防治耐蜱璃眼蜱。
