Aremu Harun K, Adekale Idris A, Azeez Luqmon A, Busari Hassan K, Adebisi Oluwaseun, Iwalewa Zarat O, Alle Olamide E, Musa Dickson A
Department of Biochemistry, Osun State University, Osogbo, Nigeria; Trans-Saharan Disease Research Centre, Ibrahim Badamasi Babangida University, Nigeria.
Department of Biochemistry, Osun State University, Osogbo, Nigeria.
Acta Trop. 2022 May;229:106384. doi: 10.1016/j.actatropica.2022.106384. Epub 2022 Feb 22.
Vector control strategies have focused on the development of effective and ecofriendly alternatives. In the present study, investigation of larvicidal and genotoxic effects of leaves of Hyptis suaveolens from four different extraction solvents (aqueous, hexane, methanol and acetone) on fourth instar larvae of Culex quinquefasciatus was carried out. Extraction was done using soxhlet apparatus and the characteristics functional group of active constituents were identified using Fourier Transform Infrared spectrophotometer. Larvicidal activities were screened using three different concentrations (50, 150 and 250 mg/mL) following WHO standard protocol and mortality was recorded after 24, 48 and 72 hr. Hexane extract showed the highest mortality (27.92, 38.75, 90.42 %; LC: 272.5, 191.3, 114.8 mg/mL), followed by aqueous extract (20.83, 34.58, 59.58 %; LC: 496.6, 392.9, 208.1 mg/mL) and acetone extract (20.83, 32.08, 59.58 %; LC: 1111.2, 393.6, 266.1 mg/mL) and methanol extract (17.92, 29.17, 52.92 %; LC: 466.0, 400.1, 272.3 mg/mL). Enzyme profile such as superoxide dismutase (SOD), glutathione-S-transferase (GST), catalase (CAT), glutathione (GSH) and alkaline phosphatase (ALP) were significantly altered in the larvae exposed to the four extracts. Phytochemical screening of all solvents extract revealed the presence of saponins, flavonoids, terpenoids and alkaloids as common constituents. Random Amplified Polymorphic DNA-Polymerase Chain Reaction (RAPD-PCR) profile implied hexane and aqueous extracts altered the DNA of larvae. Furthermore, FTIR Spectroscopic analysis revealed phenols, alcohols, aliphatic primary amines and saponins as the major groups in the extracts. Conclusively, this study established the lethal potential of extracts of H. suaveolens as alternative plant-based and eco-friendly larvicide against Cx. quinquefasciatus.
病媒控制策略一直专注于开发有效且环保的替代方法。在本研究中，对来自四种不同提取溶剂（水、己烷、甲醇和丙酮）的香蜂草叶片对致倦库蚊四龄幼虫的杀幼虫和遗传毒性作用进行了研究。使用索氏提取器进行提取，并使用傅里叶变换红外光谱仪鉴定活性成分的特征官能团。按照世界卫生组织标准方案，使用三种不同浓度（50、150和250毫克/毫升）筛选杀幼虫活性，并在24、48和72小时后记录死亡率。己烷提取物显示出最高死亡率（27.92%、38.75%、90.42%；半数致死浓度：272.5、191.3、114.8毫克/毫升），其次是水提取物（20.83%、34.58%、59.58%；半数致死浓度：496.6、392.9、208.1毫克/毫升）、丙酮提取物（20.83%、32.08%、59.58%；半数致死浓度：1111.2、393.6、266.1毫克/毫升）和甲醇提取物（17.92%、29.17%、52.92%；半数致死浓度：466.0、400.1、272.3毫克/毫升）。在接触这四种提取物的幼虫中，超氧化物歧化酶（SOD）、谷胱甘肽 - S - 转移酶（GST）、过氧化氢酶（CAT）、谷胱甘肽（GSH）和碱性磷酸酶（ALP）等酶谱发生了显著变化。对所有溶剂提取物的植物化学筛选显示，皂苷、黄酮类化合物、萜类化合物和生物碱是常见成分。随机扩增多态性DNA - 聚合酶链反应（RAPD - PCR）图谱表明，己烷和水提取物改变了幼虫的DNA。此外，傅里叶变换红外光谱分析表明，提取物中的主要基团为酚类、醇类、脂肪族伯胺和皂苷。总之，本研究确定了香蜂草提取物作为替代植物源且环保的杀幼虫剂对致倦库蚊的致死潜力。
