Introduction: Phytate is the main source of phosphorous in plants which is not digestible for monogastric animals, because they lack an insufficient amount of degrading enzyme called phytase. Thus, using plants with the ability to activate phytase in the diet of animals could be a great solution for this issue. Objectives: This study aimed to evaluate the effects of methanolic extracts of aerial parts of Rindera lanata and Euphorbia denticulata plants including leaves, stems and flowers on the activity of phytase enzyme. Methods: The investigated plants were collected from various regions of Kurdistan province, Iran. The plants were completely dried followed by grounding to extract. Enzyme assay for Rindera lanata was conducted in eight different extract concentration including 0.1, 1, 10 and 100 mg/ml as the group one, and 6.25, 12.5, 25 and 50 mg/ml as group two. However, the concentrations were different for Euphorbia denticulata with 0.001, 0.01 and 0.1 mg/ml as group one and 0.0063, 0.0125, 0.025 and 0.05 mg/ml as group two. Results: The results showed that leaf extract of Rindera lanata has a great potential to activate phytase enzyme when 100 mg/ml of extract was applied. The extract derived from flowers showed a low to moderate impact on phytase activity. The results for Euphorbia denticulata were contradictory showing activatory effects for some concentrations and inhibitory effects for others. The IC50 for leaves, stems and flowers of Rindera lanata was 124.53, 14.51 and 14.97 mg/mL, respectively. Moreover, the IC50 for leaves and flowers of Euphorbia denticulata was 0.17 and 0.0011 mg/mL. Conclusion: Overall results demonstrated that leaves and stems extract obtained from Rindera lanata could be used as a remarkable phytase activator in animal feed, but Euphorbia denticulata was not as strong as Rindera lanata.
