Avaliação do óleo essencial de alpinia zerumbet (pers.) b. l. burtt & r. m. sm. (zingiberaceae) como agente larvicida frente Aedes aegypti L.

Abstract

The significant increase in arboviral diseases such as dengue, zika, and chikungunya represents one of the major contemporary challenges to public health, especially in tropical regions like Brazil. The limited effectiveness of conventional synthetic insecticides, aggravated by the growing resistance of Aedes aegypti L., highlights the need for alternative strategies that are sustainable, effective, and environmentally safe. In this context, natural products have emerged as promising sources of bioactive compounds with potential for vector control. This study aimed to evaluate the larvicidal activity of the essential oil (EO) extracted from leaves of Alpinia zerumbet (Pers.) B.L. Burtt & R.M. Sm. (Zingiberaceae), as well as to assess its toxicity on non-target organisms. The dissertation was structured in two chapters. Chapter I presents a literature review on current vector control methods against A. aegypti, highlighting the advances and limitations of physical, chemical, biological, and genetic strategies. Despite the progress achieved in various approaches, persistent challenges remain regarding prolonged efficacy, operational costs, and social acceptance, reinforcing the importance of integrated and environmentally responsible solutions. Chapter II addresses the evaluation of larvicidal activity of the EO from A. zerumbet, whose leaves were collected in the municipality of São Luís (MA), and then subjected to drying, grinding, and hydrodistillation. Botanical identification was performed at the Maranhão Herbarium – UFMA. A morphoanatomical characterization of the leaves was also conducted to validate species authenticity. The chemical composition of the EO was determined by gas chromatography coupled with mass spectrometry (GC-MS), with p-cymene (17.42%), 4- terpineol (14,25%), and 1,8-cineole (10.52%) identified as the major constituents. Larvicidal assays, carried out according to World Health Organization (WHO) protocols, revealed an LC50 of 50.80 μg·mL⁻¹ against A. aegypti larvae, indicating significant activity. In parallel, toxicity tests using Artemia salina showed an LC50 of 293.11 μg·mL⁻¹, classifying the EO as non-toxic. The findings of this study reinforce the need for safe and effective alternatives for arbovirus control and highlight the potential of A. zerumbet essential oil as a natural larvicidal agent, combining biological efficacy with low environmental toxicity. Furthermore, the morphoanatomical features established here contribute to the authentication and traceability of the plant raw material. These findings support its future application in safer and more sustainable vector control programs. However, large-scale implementation requires further field studies and the development of technological formulations that ensure stability, economic feasibility, and prolonged effectiveness.