ACUTE TOXICITY OF CISTANCHE TUBULOSA METHANOL EXTRACT: A POTENTIAL NOVEL INSECTICIDAL COMPOUNDS AGAINST MALARIA- TRANSMITTING MOSQUITO M. Mathiyazhagan 1 , M. Baranitharan 1,2 , K. Rajaganesh 3 , Naorem Chanu Sumedha 3 and J. Gokulakrishnan* 4 1 Department of Botany, Silapathar Science College (Affiliated to Assam Science & Technology Univ.), Silapathar-787 059, India. 2 Department of Zoology, Silapathar Science College (Affiliated to Assam Science & Technology Univ.), Silapathar-787 059, India. 3 Department of Biotechnology, St. Joseph University, Dimapur - 797 115, India. 4 P.G & Research Department of Zoology, Poompuhar College (Autonomous), Melaiyur - 609 107, India. Corresponding author - J. Gokulakrishnan, *e-mail : gokulagalya@gmail.com (Received 3 July 2023, Revised 20 August 2023, Accepted 6 September 2023) ABSTRACT : Acute toxicity of Cistanche tubulosa ethanol flower extract fractions (C. tubulosa-EFEFr) was controlled and using major chemical components (MCCs) analysis, highlights of the main components on the malarial vector, Anopheles stephensi (An. stephensi). In MCCs, characterized by GC-MS analysis was carried out to be eligible for the constituents of the MFE. In MCCs analysis, a total of twenty compounds were identified in the C. tubulosa-EFE and the MCC was α-Santonin. Ovicide effect exerted by Egg Hatchability/Egg No hatchability% (EH/ENH%) ovicide effects of 100% mortality at 15, 25, 35, 45 and 55 ppm from C. tubulosa-Fr-6, against An. stephensi. The maximum repellency showed 100% protection up to 210 min at 0.45 mg/cm 2 from F-VI from C. tubulosa. The reports revealed the α-Santonin was the main constituent provides malarial control for the vector mosquito from C. tubulosa-EFEFr. Key words : Cistanche tubulosa, Anopheles stephensi, Ethanol flower extract fractions, major chemical components, pest control. How to cite : M. Mathiyazhagan, M. Baranitharan, K. Rajaganesh, Naorem Chanu Sumedha and J. Gokulakrishnan (2023) Acute toxicity of Cistanche tubulosa methanol extract: A potential novel insecticidal compounds against malaria-transmitting mosquito. Biochem. Cell. Arch. 23, 000-000. DOI: https://doi.org/10.51470/bca.2023.23.2.000, DocID: https://connectjournals.com/ 03896.2023.23.000 Biochem. Cell. Arch. Vol. 23, No. 2, pp. 000-000, 2023 ISSN 0972-5075 DocID: https://connectjournals.com/03896.2023.23.000 eISSN 0976-1772 DOI: https://doi.org/10.51470/bca.2023.23.2.000 INTRODUCTION Malaria, transmitted by the bite of infective female mosquito, Anopheles stephensi and global public health problem that mainly affects tropical countries (Balkew et al, 2021; Teshome et al, 2023), there has been an increase in malaria cases and incidence reported in 2020 and 2021. Continuously, vector control is a vital component of malaria control and elimination strategies as it is highly effective in preventing infection and reducing disease transmission. The two core interventions are insecticide- treated nets (ITNs) and indoor residual spraying (IRS) (WHO malaria fact sheets, 2019; 2023). At present, imported malaria remains a significant medical and health issue in many European countries, and non-immune travelers from malaria-free areas are very vulnerable to the disease when they become infected (WHO, 2021). Medicinal plant products have been made conventionally by the human population in a variety of rural areas globally against vector-borne diseases and parasitological diseases (Baranitharan et al, 2021a; Al- Ghanim et al, 2023). Apart from this insecticide resistance problem, there are other ecological consequences of wide use of conventional synthetic insecticides and biological activity components produced by overall medicinal plants can act as larvicides, repellency and toxin against insects (Jebanesan et al, 2020; Irrusappan et al, 2022; Serrao et al, 2022; Ahmad et al, 2023). The growing awareness of the hazards of excessive use of insecticidal globally has led researchers to search for safer and more environment friendly alternative methods for insect pest control (Deepa et al, 2015; Gokulakrishnan et al, 2016; Dhanasekaran et al, 2018; Kavitha et al, 2020; Kamaraj et al, 2023). Cistanche tubulosa (Family: Orobanchaceae) plant produce many secondary metabolites, which are biosynthetically derived from primary metabolites and constitute an important source of chemicals, which are used as pharmaceuticals, agrochemicals, flavors,