Subacute Aral Toxicity Evaluation of Two Achillea Species Methanolic Extracts Used as Botanical insecticide Against Stored‐grains Insect

Genus Achillea is represented by about 115 species in northern hemisphere, mainly in North Africa. Acillea Santolina (AS) and Achillea Agulata (AA) are strongly fragrant perennial herbs represented in Egypt that have been used by Bedouins for stomachic, anthelmintic, hyperglycemic, toothache, chest disorder, tonic, carminative, dysentery and insect repellent. Insects damage stored grains may amount to l0–40% in countries where modern storage technologies have not been introduced. Currently, the measures to control insects’ infestation in stored grains rely heavily upon the use of chemical insecticides, which pose possible health hazards and risk of contamination in food environment. Botanical insecticides may answer the need for safer compounds to protect stored grains from attack by a wide range of insects. Present study aims to evaluate the safety of AS and AA methanolic extracts (MEs) as environmentally friendly botanical insecticides used against Tripolium castinum in stored grains. The aerial parts of both species were collected from different locations of Bourg AL Arab desert nearby Alexandria, Egypt in April, 2014 at the flowering period. Plant samples were identified, dried, powdered, sieved and maintained in tightly closed dry bags until used. Plant powders were subjected to hydrodistillation to extract volatile oils (VOs) or soaked in methanol (24 hr.) to obtain the MEs. VOs were identified by GC–MS whereas MEs were subject to LC 50 test against Tripolium castinum and a subacute oral toxicity test in five rat groups to evaluate its safety. AS and AA groups received 20 mg/kg of each MEs for three consecutive days before scarified. This dose is equivalent to one fifth of the LC 50 of both AA and AS MEs against Tripolium castinum . Groups ASA and AAA received the same treatment as AS and AA but were scarified after one week (of last dose) as recovery period. Group C received saline solution as a control group. Biochemical parameters were analyzed in blood and histological investigations were carried out in liver, kidney and brain for all samples. Various constituents were identified in Acillea Santolina and Achillea Agulata VOs by GCMS scan. Major components are carveol, eugenol, alloaromadendrene, caryophyllene and germacrene. Composition variations in VOs obtained from two Achilleae species can be due to genetic differences. Substantial effects of both MEs have been detected against Tripolium castinum after 24, 48 and 72 hr. by both topical and fumigation applications. In subacute toxicity evaluation, no toxic signs, changes in behavior or mortality were detected in all groups. The histopathology study also showed no toxic effect to all samples. No significant differences have been indicated between AS, AA and C for all blood profile, lipid profile, liver and kidney functions analysis whereas significant difference in urea level has been detected in AA. On the other hand, recovery group ASA showed significant differences in platelets parameters and AAA showed significant changes in both red blood cells profile and platelets values comparing with their corresponding groups AA and AS. Although our results demonstrate promising effect of both Acillea Santolina and Achillea Agulata MEs as environmentally friendly botanical insecticide against Tripolium castinum as a stored‐grains insect, further safety assessment should be conducted to insure its health hazardous effects.