Publication: Azadırachtın’ın Galleria mellonella L. (Lepidoptera: pyralidae) hemolenfinde bulunan bazı antioksidan enzimlerine etkileri
Abstract
AZADIRACHTIN’IN Galleria mellonella L. (LEPIDOPTERA: PYRALIDAE) HEMOLENFİNDE BULUNAN BAZI ANTİOKSİDAN ENZİMLERİNE ETKİLERİ Bitkisel kökenli Azadirachtin (AZA) maddesinin, zararlı organizmalara karşı kullanıldığı ve lepidopter türlerinin bu maddeye karşı oldukça hassas olduğu bilinmektedir. Çalışmamızda, büyük balmumu güvesi Galleria mellonella L. (Lepidoptera: Pyralidae) larvalarına zorla besleme uygulaması yapılarak AZA’nın insektisidal etkileri araştırıldı. Sonuçlar, artan AZA dozlarına bağlı olarak larval yaşam süresinin uzadığını ve pupal yaşam süresinin değişmediğini gösterdi. AZA dozlarına bağlı olarak ergin yaşam süresi, pupal ve ergin ağırlıkları azaldı. Deneyler, AZA’nın LD50 ve LD99 değerlerinin sırasıyla 2.1 µg/ larva ve 4.6 µg/ larva olduğunu gösterdi. Hemolenf total protein miktarı, malondialdehit seviyesi ve antioksidan enzim aktivitelerini belirlemek için son dönem larvalara (0.16 0.01 gr) zorla besleme uygulaması yapıldı. Uygulamadan 24 ve 72 saat sonra hemolenf örnekleri alındı. Deneysel analizler beş doz AZA (0.5, 1, 1.5, 2, ve 3 µg/ larva) ile gerçekleştirildi. Hemolenf total protein miktarı 24. saatte 2 ve 3 µg/ larva dozları ile karşılaştırıldığında diğer AZA dozlarında artarken, 72. saatte yalnızca 1.5 µg/ larva dozunda arttı. Malondialdehit seviyeleri kontrol grupları ile karşılaştırıldığında 24. saatte 2 ve 3 µg/ larva dozlarında arttı. Bu sonuç, 72. saatte 1.5, 2 ve 3 µg/ larva dozlarında da gözlendi. Malondialdehit seviyeleri 1.5 µg/ larva dozu hariç 24. saatteki sonuçlarla karşılaştırıldığında 72. saatte düştü. Katalaz aktivitesi kontrollerle karşılaştırıldığında 72. saatte 0.5 µg/ larva dozu hariç diğer dozlarda artarken, 24. saatte 1, 1.5 ve 2 µg/ larva dozlarında azaldı. AZA, 72. saatte 3 µg/ larva hariç 24 ve 72. saatte bütün dozlarda süperoksit dismutaz aktivitesinde düşüşe yol açtı. Glutatyon S-transferaz (GST) aktivitesindeki artış, 24. saatte bütün AZA dozlarında belirgindi. GST aktivitesi, uygulama sonrasında 72. saatte, 24. saat ile karşılaştırıldığında, yaklaşık % 68 azalma gösterdi. Sonuç olarak, AZA G. mellonella larvaları üzerinde zamana ve doza bağlı olarak ölüme, toksik belirtilere ve oksidatif strese neden oldu.
EFFECTS OF AZADIRACHTIN ON SOME ANTIOXIDANT ENZYMES IN HEMOLYMPH OF Galleria mellonella L. (LEPIDOPTERA: PYRALIDAE) It is known that azadirachtin (AZA), a plant origin substance, is used against pest organisms and lepidopteran species are quite sensitive against this substance. In our study, the insecticidal effects of AZA were investigated via force feeding on the greater wax moth, Galleria mellonella L. (Lepidoptera: Pyralidae) larvae. The results showed that larval developmental time increased but survival time of pupa did not change depending on increasing doses of AZA. On the other hand, adult longevity, and weights of pupae and adults decreased. Bioassays revealed that the LD50 and LD99 values of AZA were 2.1 and 4.6 µg/ larva, respectively. To determine the amount of total protein, malondialdehyde level and antioxidant enzyme activities in hemolymph, force-feeding application is performed on the last instars (0.16 0.01 g). After 24 and 72 hours post applications, hemolymph samples were collected. Experimental analyses were performed with five doses of AZA (0.5, 1, 1.5, 2, and 3 µg/ larva). The amount of total protein in larval hemolymph increased at all AZA doses whereas a considerable decrease was observed at 2 and 3 µg/ larva doses at 24 h, and only an increase was evident at 1.5 µg/ larva at 72 h. Malondialdehyde levels increased at 2 and 3 µg/ larva doses at 24 h in comparison with control groups. This result was also observed at 1.5, 2, and 3 µg/ larva doses at 72 h. Malondialdehyde levels were lower at 72 h when compared with those of 24 h at all doses except for 1.5 µg/ larva. Catalase activity decreased at 1, 1.5, and 2 µg/ larva doses at 24 h whereas increased at all other doses except for 0.5 µg/ larva dose at 72 h when compared with controls. AZA led to a decline in superoxide dismutase activity at all experimental doses at 24 and 72 h except for 3 µg/ larva doses at 72 h. An increase in glutathion S-transferase (GST) activity was obvious at all AZA doses at 24 h. AZA displayed about 68% decline in GST activity at 72 h post treatments compared with those of 24 h. Consequently, AZA caused dose and time dependent mortality, toxic symptoms, and oxidative stress on G. mellonella larvae.
EFFECTS OF AZADIRACHTIN ON SOME ANTIOXIDANT ENZYMES IN HEMOLYMPH OF Galleria mellonella L. (LEPIDOPTERA: PYRALIDAE) It is known that azadirachtin (AZA), a plant origin substance, is used against pest organisms and lepidopteran species are quite sensitive against this substance. In our study, the insecticidal effects of AZA were investigated via force feeding on the greater wax moth, Galleria mellonella L. (Lepidoptera: Pyralidae) larvae. The results showed that larval developmental time increased but survival time of pupa did not change depending on increasing doses of AZA. On the other hand, adult longevity, and weights of pupae and adults decreased. Bioassays revealed that the LD50 and LD99 values of AZA were 2.1 and 4.6 µg/ larva, respectively. To determine the amount of total protein, malondialdehyde level and antioxidant enzyme activities in hemolymph, force-feeding application is performed on the last instars (0.16 0.01 g). After 24 and 72 hours post applications, hemolymph samples were collected. Experimental analyses were performed with five doses of AZA (0.5, 1, 1.5, 2, and 3 µg/ larva). The amount of total protein in larval hemolymph increased at all AZA doses whereas a considerable decrease was observed at 2 and 3 µg/ larva doses at 24 h, and only an increase was evident at 1.5 µg/ larva at 72 h. Malondialdehyde levels increased at 2 and 3 µg/ larva doses at 24 h in comparison with control groups. This result was also observed at 1.5, 2, and 3 µg/ larva doses at 72 h. Malondialdehyde levels were lower at 72 h when compared with those of 24 h at all doses except for 1.5 µg/ larva. Catalase activity decreased at 1, 1.5, and 2 µg/ larva doses at 24 h whereas increased at all other doses except for 0.5 µg/ larva dose at 72 h when compared with controls. AZA led to a decline in superoxide dismutase activity at all experimental doses at 24 and 72 h except for 3 µg/ larva doses at 72 h. An increase in glutathion S-transferase (GST) activity was obvious at all AZA doses at 24 h. AZA displayed about 68% decline in GST activity at 72 h post treatments compared with those of 24 h. Consequently, AZA caused dose and time dependent mortality, toxic symptoms, and oxidative stress on G. mellonella larvae.