Iskender Emre

Changes in Antioxidative Enzyme Activity, Glycogen, Lipid, Protein, and Malondialdehyde Content in Cadmium-Treated Galleria mellonella Larvae

ABSTRACT In this study, we analyzed the effects of cadmium (1.25, 2.5, 5, 10, 20, and 40 mg per 100 g of nutrient) on total protein, lipid, and glycogen levels, lipid peroxidation (MDA), superoxide dismutase (SOD) and catalase (CAT) activities, and metal accumulation in Galleria mellonella L. High concentrations of Cd (20 and 40 mg) significantly lowered total protein, lipid, and glycogen levels. MDA level significantly increased when the nutrient contained 5 mg and more of Cd, whereas SOD activity significantly increased at Cd concentrations starting from 1.25 mg. CAT activity significantly decreased at all concentrations. Metal accumulation also significantly increased in a dose-dependent manner. These changes observed on activity of antioxidant enzymes, energy reserves, MDA content, and accumulation levels of Cd can be used as a reliable biomarker of environmental heavy metal pollution in model insect G. mellonella.

Role of Lipids, Amino Acids, and Sucrose on the Total Adult and Female Emergence, and Content of Glycogen and Protein in Pimpla turionellae (Hymenoptera: Ichneumonidae)

ABSTRACT We investigated the effects of a diet prepared with varying lipid, amino acid, and sucrose contents on the total adult and female emergence and the total glycogen and protein levels in the life span of female Pimpla turionellae. Although the meridic diet containing any lipids had no significant effect on the ratio of emerging adults, increasing and decreasing the amount of lipids in the diet significantly affected female emergence. Increasing the amino acid content by 50% or omitting it in the control diet decreased the total adult ratio compared to the control diet. A maximum of 85.18% of adults emerged in this group when the insects were fed a synthetic diet containing 1.5 g of amino acid mixture. The insects lived for only 7 d without sucrose, whereas increasing and decreasing the amount of sucrose in the diet affected the total female emergence positively relative to the control diet. The meridic diet increased the emergence of P. turionellae females but reduced their total glycogen. The decrease in female emergence observed when sucrose and amino acids are removed is explained by a decrease in the phagostimulation and metabolic protein deviation. Ascertaining the exact combination of carbohydrates and proteins is essential for successful rearing of these insects.

Alterations in Antioxidant Enzyme Activity, Lipid Peroxidation, and Ion Balance Induced by Dichlorvos in Galleria mellonella (Lepidoptera: Pyralidae)

ABSTRACT Dichlorvos (DDVP; 2,2-dichlorovinyl dimethyl phosphate) is an organophosphate insecticide widely used in the control of pests. This study aims to determine the changes caused by DDVP in the antioxidant enzyme activity, lipid peroxidation level, and ion content of a model organism, Galleria mellonella L. (Lepidoptera: Pyralidae). Larvae of G. mellonella were fed sublethal concentrations of DDVP (2, 4, 6, and 8 µg/l00 g feed). Exposure to DDVP resulted in induction of superoxide dismutase and catalase activities, and lipid peroxidation in larvae. Potassium and sodium ion levels were significantly altered by DDVP exposure. These results suggest that DDVP causes oxidative stress and lipid peroxidation and alters the antioxidant enzyme activities and ion balance in G. mellonella larvae. Additionally, these results indicate that G. mellonella is a useful model for testing the effects of insecticides.