摘要Synthesis of zinc oxide nanoparticles(ZnO-NPs)via green method is an outstanding alternative to conventional/regular methods;however,the safety or toxicity of the biosynthesized ZnO-NPs in vivo is not fully explored.This study was conducted to evaluate the protective efficiency of cinnamaldehyde-loaded chitosan nanoparticles(Cin@CSNPs)against oxidative damage and genotoxicity of ZnO-NPs in mice.ZnO-NPs were biosynthesized using the extract of fresh leaves of Mentha pulegium L.Cin was extracted from cinnamon essential oil,and was loaded into chitosan nanoparticle(Cin@CSNPs).Both ZnO-NPs,Cin@CSNPs and CSNPs were characterized.The in vitro release of Cin@CSNPs was determined.In the biological study,6 groups of male BALB/c mice were treated by gavage for 3 weeks as follows,control group,the group received ZnO-NPs(25 mg/kg b.w),the groups received Cin@CSNPs at low dose(50 mg/kg b.w)or high dose(100 mg/kg b.w),and the groups received ZnO-NPs plus Cin@CSNPs at the 2 tested doses.Blood and tissue samples were collected for different biochemical,genetical and histological studies.The particle size of ZnO-NPs,CSNPs,and Cin@CSNPs were(20.78±2.60),(170.0±3.7),and(218.23±2.90)nm,and ξ-potential were(32.7±4.6),(8.32±0.27)and(4.80±0.21)mV,respectively.ZnO-NPs disturbed the biochemical and oxidative stress indices,AFP,CEA,TNF-α,chromosomal aberrations in somatic and germ cells,and sperm abnormality along with severe pathological changes in the hepatic,renal,and testicular tissues.Cin@CSNPs improved significantly all the parameters tested and the histological picture in a dose-dependent.Therefore,the biosynthesized ZnO-NPs exhibit oxidative damage and genotoxicity,and Cin@CSNPs have potential protective effects against the risks of ZnO-NPs and may be a promising tool to overcome the challenges of using Cin in food and pharmaceuticals applications.