Efecto de firerentes concentraciones de nanoparticulas de oxido de zinc biosintetizadas mediante extractos acuosos de hojas de Azadirachta indica y Bixa orellana sobre larvas de III y IV estadio de Aedes aegypti
No Thumbnail Available
Date
2025
Authors
Journal Title
Journal ISSN
Volume Title
Publisher
Universidad Nacional de Trujillo
Abstract
Aedes aegypti es el vector principal de la enfermedad del dengue, en los últimos dos años se ha reportado el incremento de casos causando un rebrote de esta enfermedad en el Perú. Por tal motivo en la presente investigación se evaluó el efecto de las nanopartículas de óxido de zinc (NPsZnO) obtenidas mediante extractos acuosos de hojas de Azadirachta indica y Bixa orellana en larvas de A. aegypti. Para lo cual se empleó un Diseño en Bloques Completamente al azar (DBCA), donde se asignaron 20 unidades muestrales en un grupo control y cuatro tratamientos (62.5, 125, 250 y 500 ppm) que se desarrollaron por triplicado, los bioensayos se llevaron a cabo en condiciones de laboratorio a una temperatura de 27°C ±2°C y humedad relativa de 75 - 80% con un fotoperiodo artificial de 12 h luz: 12 h oscuridad. Los porcentajes de mortalidad muestran que tanto para neem y achiote a 250 ppm de NPsZnO, se alcanzan los más altos porcentajes de mortalidad 6.6 a las 72 horas de exposición en larvas de III estadio, mientras que para las larvas IV indican un porcentaje de mortalidad (5) para neem a 125 y 250 ppm a las 72 horas de exposición. Sin embargo, el valor más alto se alcanzó a 31.25 ppm y al mismo tiempo anterior el porcentaje de mortalidad fue de 5 para el achiote. La observación histológica evidencia la acumulación y agregación de estas NPsZnO a nivel de la totalidad del enteron de la larva IV, lo que pondría de manifiesto la incapacidad metabólica para su degradación. Para la inhibición de crecimiento evidencian una relación inversamente proporcional entre las diferentes concentraciones de (NPsZnO) sobre el porcentaje de inhibición del crecimiento en larvas IV de A. aegypti, alcanzando a los 21 días valores de 46.7 (neem) y 48.4 (achiote) a 31. 25 ppm. Este método se muestra como una alternativa fiable y prometedora para el control de la población de A. aegypti, contribuyendo a la lucha contra el dengue de manera ecológica y efectiva.
Aedes aegypti is the primary vector of dengue fever. In the last two years, an increase in cases has been reported, leading to a resurgence of the disease in Peru. Therefore, the aim of this study was to evaluate the effect of zinc oxide nanoparticles (NPsZnO) synthesized from aqueous extracts of Azadirachta indica and Bixa orellana on A. aegypti larvae. A Completely Randomized Block Design (CRBD) was employed, with 20 experimental units assigned to a control group and four treatments (62.5, 125, 250, and 500 ppm), each carried out in triplicate. Bioassays were conducted under laboratory conditions with a temperature of 27°C ± 2°C, relative humidity of 75-80%, and an artificial photoperiod of 12 hours light: 12 hours darkness. Mortality percentages indicated that both neem and achiote at 250 ppm of NPsZnO resulted in the highest mortality rates, reaching 6.6% after 72 hours of exposure in third-stage larvae, while for fourth-stage larvae, a mortality rate of 5% was recorded for neem at 125 and 250 ppm after 72 hours of exposure. However, the highest mortality rate was observed at 31.25 ppm, where the mortality percentage for both neem and achiote was also 5%. Histological observations revealed the accumulation and aggregation of NPsZnO throughout the entire enteron of the fourth-stage larvae, suggesting a metabolic inability to degrade the nanoparticles. In terms of growth inhibition, a significant inverse relationship was observed between the various concentrations of NPsZnO and the growth inhibition percentage in fourth-stage larvae of A. aegypti, with values of 46.7% (neem) and 48.4% (achiote) at 31.25 ppm after 21 days. This method proves to be a promising and eco-friendly alternative for controlling A. aegypti populations, offering an effective contribution to the fight against dengue.
Aedes aegypti is the primary vector of dengue fever. In the last two years, an increase in cases has been reported, leading to a resurgence of the disease in Peru. Therefore, the aim of this study was to evaluate the effect of zinc oxide nanoparticles (NPsZnO) synthesized from aqueous extracts of Azadirachta indica and Bixa orellana on A. aegypti larvae. A Completely Randomized Block Design (CRBD) was employed, with 20 experimental units assigned to a control group and four treatments (62.5, 125, 250, and 500 ppm), each carried out in triplicate. Bioassays were conducted under laboratory conditions with a temperature of 27°C ± 2°C, relative humidity of 75-80%, and an artificial photoperiod of 12 hours light: 12 hours darkness. Mortality percentages indicated that both neem and achiote at 250 ppm of NPsZnO resulted in the highest mortality rates, reaching 6.6% after 72 hours of exposure in third-stage larvae, while for fourth-stage larvae, a mortality rate of 5% was recorded for neem at 125 and 250 ppm after 72 hours of exposure. However, the highest mortality rate was observed at 31.25 ppm, where the mortality percentage for both neem and achiote was also 5%. Histological observations revealed the accumulation and aggregation of NPsZnO throughout the entire enteron of the fourth-stage larvae, suggesting a metabolic inability to degrade the nanoparticles. In terms of growth inhibition, a significant inverse relationship was observed between the various concentrations of NPsZnO and the growth inhibition percentage in fourth-stage larvae of A. aegypti, with values of 46.7% (neem) and 48.4% (achiote) at 31.25 ppm after 21 days. This method proves to be a promising and eco-friendly alternative for controlling A. aegypti populations, offering an effective contribution to the fight against dengue.
Description
Keywords
Larvas de Aedes aegypti, nanopartículas, porcentaje de mortalidad, porcentaje de inhibición de crecimiento