Ovicidal lectins from Moringa oleifera and Myracrodruon urundeuva cause alterations in chorionic surface and penetrate the embryos of Aedes aegypti eggs

Abstract

BACKGROUND: Lectins from Moringa oleifera seeds (WSMoL), Myracrodruon urundeuva bark (MuBL), and heartwood (MuHL) are larvicidal agents against Aedes aegypti; in addition, WSMoL is an ovicidal agent against this mosquito. In this work, we evaluated the ovicidal activity of MuBL and MuHL by determining the concentrations that reduce the hatching rates by 50% in 72 h (EC 50 ). The effects of WSMoL, MuBL, and MuHL on the ultrastructure of the eggs' surface were assessed by scanning electron microscopy (SEM). In addition, the ability of these lectins to penetrate the eggs was investigated by using conjugates of the lectins with fluorescein isothiocyanate (FITC). RESULTS: MuBL andMuHL were ovicidal agents with EC 50 of 0.26 and 0.80 mg/mL (260 and 800 ppm), respectively. SEM images of eggs treated with WSMoL for 24 h revealed discontinuity of the exochorionic network and the absence of the exochorionic cells and their tubercles. After 48 and 72 h of incubation, strong deformation and degeneration of egg surfaces were observed. In MuBL and MuHL-treated eggs, the presence of lumps on the surface of the eggs, disappearance of the exochorionic network and the decrease and deformation of tubercles were observed. Lastly, fluorescence microscopy revealed that the three lectins were able to enter the eggs and reach the digestive tract of the embryos. CONCLUSION: WSMoL, MuBL, and MuHL are ovicidal agents on A. aegypti that have differing efficiencies in terms of how they cause alterations in the chorionic surface and in terms of their ability to penetrate the eggs.

Extract from Opuntia ficus‐indica cladode delays the Aedes aegypti larval development by inducing an axenic midgut environment

“…In addition, lectins from M. oleifera seeds and Myracrodruon urundeuva bark and heartwood were embryotoxic to Ae. aegypti , damaging the eggs chorionic surface and penetrating the embryos body, reaching their intestinal tract (Alves et al, 2020).…”

Research trends of Moringa oleifera Lam as Remedy toward Cattle's embryo according to the frequently used words in content of papers and citations

“…Ruminant species had Cellulose enzymes so that Moringa oleifera 's leaf extract could be digested in the Gastro intestine of Ruminants easier and faster. The green leaf of Moringa oleifera consists of the highest chlorophyll that is rich in cellulose enzymes and can only be digested by ruminants [ 18 ]. Enzymes of cellulose can be extracted by cellulose enzymes that are produced by Gastro intestine s of ruminant types of animals only.…”

Ovicidal activity of spirotetramat and its effect on hatching, development and formation of Frankliniella occidentalis egg

“…In further study of the effect of spirotetramat on F. occidentalis eggs, SEM imaging showed that the egg surface was shrunken, the pores were sunken and the outer chorion fell off. The eggs of Aedes aegypti were seriously deformed and degenerated after being treated with ovicidal lectins from Moringa oleifera and Myracrodruon urundeuva : the outer chorion of the egg shell disappeared, the nodules were few and deformed and the egg surface was covered with dense aggregates 21 . Cotton leafworm eggs treated with mahlab ( Prunus mahaleb L.) kernel oil showed abnormal granular protrusions or protrusions on the egg surface, and even rupture of the chorionic surface; the egg surface wrinkles increased after mahlab oil treatment 22 .…”