Abstract. CC-BY 4.0 International license It is made available under a (which was not peer-reviewed) is the author/funder, who has granted bioRxiv a license to display the preprint in perpetuity.The copyright holder for this preprint . http://dx.doi.org/10.1101/347278 doi: bioRxiv preprint first posted online Jun. 14, 2018; 26Schistosomiasis is one of the most socioeconomically exhausting parasitic 27 infection in tropical and subtropical areas. Praziquantel (PZQ), the only common 28 schistosocidal drug in use, is not efficient enough for treatment of immature infection. 29Arabic gum (AG) is a complex polysaccharide acts as anti-oxidant which modulates the Author summary 46Schistosomiasis is a major public health threat in many parts of the world, it 47 affects more than 240 million people in more than 70 countries and almost 800 million 48 people are at risk of acquiring this disease. Serious consequences and disabilities might . CC-BY 4.0 International license It is made available under a (which was not peer-reviewed) is the author/funder, who has granted bioRxiv a license to display the preprint in perpetuity.The copyright holder for this preprint . http://dx.doi.org/10.1101/347278 doi: bioRxiv preprint first posted online Jun. 14, 2018;

Praziquantel (PZQ), the only common schistosocidal drug in use, is not efficacious for treatment of immature schistosomiasis infection. Arabic gum (AG) is a complex polysaccharide that acts as an antioxidant which modulates the inflammatory and/or immunological processes. This study explores for the first time, the antischistosomal properties of AG in mice infected with the immature stage of Schistosoma mansoni (S. mansoni). Mice were divided into four groups: control group (infected nontreated), AG treated group, PZQ treated group, and AG+PZQ treated group. Oral administration of AG in a dose of 1 g/kg body weight, daily for 3 consecutive weeks post-infection (PI) resulted in a statistically significant (P-value 0.002 and 0.008 respectively) lower worm burden in both AG group and AG+PZQ group compared to PZQ and control groups. AG+PZQ group always showed the best results when compared with other groups regarding tissue egg load and oogram pattern. AG, both alone and in combination with PZQ, decreased the granuloma number and diameter; with increasing the cellularity and the number of degenerated Schistosoma eggs inside granulomas. Results obtained by this work elucidated a promising AG bioactivity against S. mansoni immature stages and provided a platform for subsequent experimental studies to illuminate the academia more about this novel and " green" antischistosomal agent.