الفهرس 
English CoverOnly 14 pages are availabe for public view
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Abstract
This study evaluated the eco-toxicological parameters of two chlorophyll derivatives, copper chlorophyllin (Cu-chlorophyllin) and magnesium chlorophyllin (Mg-chlorophyllin) on viability of honey bee. Chlorophyll and its derivatives have a wide range of applications such as coloring in food additives and photopesticide against medical and agricultural pests. The results of Cu-chlorophyllin and Mgchlorophyllin using different concentrations in honey bee’s feeding bait indicated their efficiency on honey bee’s viability as a function of concentration and exposure time. Honey bees’ mortality rate was 10% within the range 10-6 7x10-6 M/L and reached 25% at 10-5 M/L compared to 5% mortality in control samples. The LC50 of both derivatives showed the Mg-chlorophyllin was less toxic than Cu-chlorophyllin on bee’s viability. The maximum mortality was 14% and 21% for Mg-chlorophyllin and Cuchlorophyllin respectively. Semi-field experiment revealed that the natural activity of honey bee workers outside the hive reduced the effect of chlorophyll derivatives on honey bees’ viability of laboratory obtained data. The protein concentration measured in body homogenate of bees fed on Cuchlorophyllin was higher than that fed on Mg-chlorophyllin and the highest concentration has been recorded in day 2 (2.1± 0.09 µg/µl). The increased protein concentration suggested an antioxidant/ antioxidant enzyme synthesis due to chlorophyllin derivatives administration. Next, the Total Antioxidant Capacity (TAC) measured in forage honeybee body homogenate fed on chlorophyllin derivatives and exposed to light for three days. TAC was higher in worker bees fed on Cuchlorophyllin than Mg-chlorophyllin. Also, both the TAC measured for Cu and Mgchlorophyllin fed bees which exposed to sun light was higher than that measured in field collected bees (FC), dark control treated (TD) and light control (CL) fed in sugar solution alone. Superoxide dismutases (SOD) antioxidant activity was higher in body homogenate of honey bee fed on Cu-chlorophyyllin exposed to sun light, TL (0.32± 0.04663 U/µg protein). This result confirms the hypothesis that increased metal concentrations may affect the honey bee oxidative status, as it is well known that toxic metals Cu ion induce oxidative stress and stimulate antioxidative protection mechanisms. GST is another member of antioxidant family which is neutralized toxic compounds by way of conjugating them to glutathione for future removal from the organism. The highest GST activity was recorded in the body homogenate of Cu-chlorophyllin fed bees exposed to light, TL (3.07 ± 0.17 U/µg proteins). The results of enzymes assay in this study confirm a new rapid diagnostic tool to assess an integrated environmental risk assessment of multiple stressors on bees, i.e. chlorophyllin derivatives. Finally, the comet assay is utilized to reveal genotoxicity of photo-pesticides on worker forage bee. The DNA damage was measured as (% DNA in Tail). It is presented a clear and significant indication of genotoxicity of chlorophyllin derivatives. The % DNA damage was 24.73 ± 1.65 and 16.34 ±1.43 in the bee gut cells fed on Cu-chlorophyllin (10-5 M/L) and Mg-chlorophyllin (3x10-3 M/L) which exposed to sun light (TL). The minimum % DNA in tail was measured in sugar fed bees exposed to light, CL (12.88 ±2.44). However the dark control in Cu-chlorophyllin was higher than Mgchorophyllin fed bee (17.92 ±1.89 and 13.67 ±1.49 respectively). This study present an enzymatic and genotoxic assessment of domesticated honey bee response to photopesticide exposures which could be critical to determine non-target pesticide impacts on such economically important insect.