Al-Adilee et al (2020): Treatment of E. histolytica with Rosmarinus officinalis March 2020 Vol. 23 Issue 5 298 ROLE OF Rosmarinus officinalis PHENOLIC COMPOUNDS IN TREATMENT OF Entamoeba histolytica INFECTION Adwa Fezaa Jassim 1 , Yaseen Majid Salman AL-Adilee 2* , Aseel Ahmed Mustafa 3 1. Directorate general of education in Salah Al-Deen department of Samarra, Iraq 2. Microbiology Branch, College of medicine, Ninevah University, Iraq 3. Ministry of Education Saladin Section, Alnajat Intermediate School for Girls, Samarra, Iraq *Corresponding author E-mail: yaseen.salman@uoninevah.edu.iq (Al-Adilee) ABSTRACT The present study was designed to detect role of phenolic compounds against the E. histolytica. The study used 20 adult male rats that distributed to four groups (each group consist 5 rats); control group that received normal saline, second group rat administrated with E. histolytica at dose 10 3 cyst/ml. third group rat administrated with E. histolytica at dose 10 3 cyst/ml and treated with 50ug/ml of phenolic compoundsfor four weeks. Fourth group rat administrated with E. histolytica at dose 10 3 cyst/ml and treated with 100ug/ml of phenolic compoundsfor four weeks. The results show high significant increased (P < 0.05) in levels AST, ALT and MDA with high significant decreased (P < 0.05) in levels of catalase in second group compared with control group. The results of third and fourth groups show non-significant changes (P < 0.05) in all parameters compare with control group when using phenolic compounds. About the histological changes, second group show degeneration of hepatocytes with thickening wall of central vein and infiltration of mono- nucleated inflammatory. After treatment by using phenolic compounds, tissues of liver appear semi-normal in third and fourth groups. It was concluded that phenolic compounds has arole against E. histolytica. Keywords: E. histolytica, Rosmarinus officinalis, phenolic compounds, oxidative stress, liver functions. How to cite this article: Al-Adilee YMS, Jassim AF, Mustafa AA (2020): Role of Rosmarinus officinalis phenolic compounds in treatment of Entamoeba histolytica infection, Ann Trop Med & Public Health ; 23 (5): S298-S303. DOI: http://doi.org/10.36295/ASRO.2020.2351 INTRODUCTION Amoebiasis, or amoebic dysentery, is a term used to describe an infection caused by the protozoan Entamoeba histolytica [1] . Most infections are asymptomatic, but invasive intestinal disease may occur manifesting with several weeks of cramping, abdominal pain, watery or bloody diarrhea, and weight loss [2] . Infection with E. histolytica has been estimated to be as high as 50% in some developing countries as South and Central America, Africa and Asia [3] .Entamoeba histolytica occurs in the following forms, the trophozoites, precyst, cyst, metacyst, and metacystictrophozoite. The trophozoite is the active stage that moves, feeds, and divides [4,5] . Rosmarinus officinalis L. is a medicinal plant that belongs to the Lamiaceae family and is commonly known as rosemary [6] . R. officinalis exerts various pharmacological activities such as antibacterial [7] , antidiabetic [8] , anti-inflammatory [9] , antitumor [10] and antioxidant [11] . Generic terms ‘phenolic compounds’, ‘phenolics’ or ‘polyphenolics’ refer to more than 8,000 compounds found in the plant kingdom and possessing at least an aromatic ring with one or more hydroxyl substituents, including