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Thesis Issued 2026-09-07 EN

Determination of DDT and Malathion Resistance in Houseflies of Karachi Region and Their Effects on Protein and Enzyme Pattern

Author: Kahkashan Akhtar

Abstract

Effect of DDT and malathion was observed on quantitative variation in protein (total protein and soluble protein), free amino acids, enzymes (acid phosphatase, alkaline phosphatase, cholinesterase, LDH, GOT, GPT and amylase), carbohydrate (glycogen), RNA, DNA, TLC, electrophoresis, GLC (for determination of pesticide), HPLC (for estimation of protein and pesticides) against the adult houseflies Musca domestica Susceptible PCSIR Strain, DDT Resistant Holland Strain and Resistant Malir Strain. The LD50 of DDT was 2.0 µg/fly in PCSIR Strain, 8.8 µg/fly in Holland Strain and 19.0 µg/fly in Malir Strain, while the LD50 of malathion was 2.0 µg/fly in PCSIR Strain, 2.2 µg/fly in Holland Strain and 8.8 µg/fly in Malir Strain. On the basis of toxicity as shown above PCSIR Strain was found to be susceptible to both the compounds, while Hollanp Strain has 4.4 fold resistance against DDT and slight against malathion and Malir Strain has approximately 10.0 fold resistance against DDT and 5.0 fold against malathion. In vivo effects of pesticides were studied in houseflies. Biochemical estimation (colorimetry) revealed that acetone (check) in PCSIR Strain decreased the activity of total protein 33.3% while DDT decreased 55.5% of activity. In Holland Strain the acetone (check) increased 14.4% activity of total protein, while DDT increased the activity 31.6%, while in Malir Strain, the acetone (check) increased the activity of total protein 17.2% and DDT increased 45.6% activity. In PCSIR Strain, malathion decreased 38.2% activity of total protein. In Holland Strain, malathion increased 6.4% activity. In Malir Strain, malathion increased 14.7 activity. Similar results were obtained in the case of soluble proteins. %% In PCSIR Strain, acetone (check) decreased 7.6% activity of free amino acids, while DDT decreased 13.8% activity. In Holland Strain, acetone (check) increased 3.9% activity of free amino acids, while DDT increased 8.5% activity. In Malir Strain acetone (check) increased 18.7% activity of free amino acids, while DDT increased 40.8% activity. In PCSIR Strain, malathion decreased 12.5% activity of free amino acids while in Holland Strain it increased 3.1% activity and in Malir Strain it increased 27.9% activity. In PCSIR Strain, acetone (check) decreased the activity of acid phosphatase 5.42% in supernatant and 6.87% in pellet, while DDT decreased 24.12% activity in supernatant and 35.18% in pellet. In Holland Strain, acetone (check) increased the activity of acid phosphatase 10.97% in supernatant and 5.81% in pellet, while DDT increased the activity 24.00% in supernatant and 10.83% in pellet. In Malir Strain, acetone (check) increased the activity of acid phosphatase 1.35 % in supernatant and 9.83 % in pellet, while DDT increased the activity 55.15% in supernatant and 38.14% in pellet. In PCSIR Strain, malathion decreased the activity of acid phosphatase 23.07% in supernatant and 30.47% in pellet, while in Holland Strain it increased 18.05% activity in supernatant and 10.32% in pellet, and in Malir Strain it increased 52.26% activity in supernatant and 14.52% in pellet. Similar results were found in all the other enzymes i.e. inhibition in PCSIR Strain and activation in Holland Strain as well as in Malir Strain. In PCSIR Strain, acetone (check), decreased the activity of glycogen 8.32%, while DDT decreased 13.97% activity. In Holland Strain, acetone (check), increased the activity 1.23%, while DDT increased 1.67%. In Malir Strain, acetone (check), increased 2.32%, while DDT increased 3.73% activity. In PCSIR Strain, malathion decreased the activity of glycogen 3.66%, while in Holland Strain it increased 1.26%, and in Malir Strain it increased 1.71% activity. In PCSIR Strain, acetone (check), decreased the activity of RNA 10.0%, while DDT decreased 38.57% activity. In Holland Strain acetone (check), increased the activity 10.71%, while DDT increased 48.57% activity. In Malir Strain, acetone (check), increased the activity 25.80%, while DDT increased 60.0% activity. In PCSIR Strain, malathion decreased the activity of RNA 21.79%, while in Holland Strain it increased 4.65% activity and in Malir Strain it increased 47.91% activity. Similar results were obtained in the case of DNA. In PCSIR Strain, DDT treated flies with 2.0 µg/fly, two metabolites were inhibited. In Holland Strain DDT treated flies with 8.8 µg/fly, one metabolite increased. In Malir Strain DDT treated flies with 19.0 Hg/fly, two metabolites increased. In PCSIR Strain, malathion treated flies with 2.0 µg/fly, inhibited the activity of all the metabolites, while in Holland Strain the activity of metabolites inceased but the number of metabolites remained same as in normal, while in Malir Strain, one more metabolite was observed with increase in activity. In PCSIR Strain during electrophoresis, DDT treated flies with 10.0 µg/fly inhibited four bands. In Holland Strain, DDT treated flies with 15.0 µg/fly increased three bands. In Malir Strain, DDT treated flies with 15.0 µg/fly increased three bands. In PCSIR Strain during electrophoresis, malathion treated flies with 10.0 µg/fly inhibited two bands. In Holland Strain, malathion treated flies with 15.0 µg/fly increased two bands. In Malir Strain, malathion treated flies with 15.0 µg/fly increased two bands. Similar results were found in the case of acid phosphatase and in alkaline phosphatase, electrophoretically. Estimation of DDT by GLC in PCSIR Strain shows that 59.69 ng/fly DDT is found in hexane extracted sample and 55.74 ng/fly in diethylether extracted sample, after the treatment with 2.0 µg/fly. In Holland Strain 18.3 ng/fly DDT is found in hexane extracted sample and 17.1 ng/fly in diethylether extracted sample. In Malir Strain 4.35 ng/fly DDT is foud in hexane extracted sample and 1.29 ng/fly in diethylether extracted sample. Estimation of proteins by HPLC in PCSIR Strain, DDT treatment with 2.0 µg/fly inhibited three protein peaks. In Holland Strain, DDT treatment with 8.8 µg/fly increased four protein peaks. In Malir Strain, DDT treatment with 19.0 µg/fly increased three peaks. In PCSIR Strain, malathion treatment with 2.0 µg/fly inhibited one protein peak. In Holland Strain, malathion treatment with 2.2 µg/fly increased three peaks. In Malir Strain, malathion treatment with 8.8 µg/fly increased three peaks. Estimation of DDT by HPLC in PCSIR Strain after the treatment with 2.0 µg/fly, showed 61.5 ng/fly DDT. In Holland Strain, after the treatment with 8.8 µg/fly, it showed 25.0 ng/fly DDT. In Malir Strain after the treatment with 19.0 µg/fly, it showed 10.0 ng/fly DDT. Estimation of malathion PCSIR Strain, after the treatment with 2.0 µg/fly showed 225 ng/fly malathion. In Holland Strain, after the treatment with 2.2 µg/fly showар 187.5 ng/fly of malathion. In Malir Strain, after the treatment with 8.8 µg/fly showed 165.0 ng/fly of malathion.