Biomedicine: 2021; 41(4): 724-731 October - December 2021 DOI: https://doi.org/10.51248/.v41i4.1365 Biomedicine- Vol. 41 No. 4: 2021 Research article Evaluation of in vitro antioxidant, anti-inflammatory, anticoagulant and antiplatelet potential of Rhus mysorensis Ghouseul Azam 1 , Sathisha G. Jayanna 1 , Anitha Nelliankla 1 , Vasanthraj Boraiah 1 , Sujatha M. Hanumegowda 1 , Devaraja Sannaningaiah 4 , Poornima D. Vijendra 3 , Vadlapudi Kumar 3 , Riaz Mahmood 2 1 Department of Biochemistry, 2 Department of Biotechnology, Kuvempu University, Jnanasahyadri, Shankaraghatta 577 451, Shivamogga, Karnataka, India 3 Department of Biochemistry, Davanagere University, Shivagangothri, Davanagere - 577 002, Karnataka, India 4 Department of Studies and Research in Biochemistry and Centre for Bioscience and Innovation, Tumkur University, Tumkur- 572103, Karnataka, India (Received: September 2021 Revised: October 2021 Accepted: October 2021) Corresponding author: Sathisha G. Jayanna. Email: satishlec@gmail.com ABSTRACT Introduction and Aim: Since ancient times human beings are using plant-based medicines for the treatment of various ailments, especially in the rural areas, due to their availability and affordability. Rhus mysorensis (RM) is widely used as a traditional medicine to treat various ailments. Owing to its potential medicinal value, the present study was designed to explore the in vitro antioxidant, anti-inflammatory, anticoagulant and antiplatelet properties of purified column fraction of RM. Materials and Methods: The methanol extract of stem bark powder was sequentially fractioned by solvent partitioning. The liquid methanol fraction was further fractionated by column chromatography using gradient elution. Eluted fractions were analyzed using HPLC for percentage purity and yield. The fraction with higher percentage of purity and yield was assessed for in vitro antioxidant activity by measuring SOD and GPx activities, anti-inflammatory activity by the inhibition of nitric oxide (NO) production in LPS induced RAW264.7 cells, anticoagulation by plasma recalcification time and antiplatelet activity by agonists induced platelet aggregation respectively. Results: The antioxidant potency of column fraction (B8) revealed that, highest enzyme activities were recorded at a concentration of 320μg/ml. The enzyme activity was found to be 2.45 U/ml for SOD and 135.75 U/L for GPx respectively. Purified column fraction (B8) of RM significantly reduces the production of NO in LPS stimulated RAW 264.7 cell lines at 320g/ml concentration with 31.90% of inhibition. The anticoagulant activity of purified fraction was determined in terms of plasma recalcification time. Interestingly, the fraction showed the most potent anticoagulant activity both in PRP and PPP as it prolonged the clotting time. Conclusion: The findings indicate that the stem bark of RM possesses potent antioxidant, anti-inflammatory, anticoagulant and antiplatelet activities, supporting the use of this species for treating oxidative stress-induced inflammatory diseases. Further, bioactivity guided fractionation studies to characterize and identify specific phytochemicals responsible for these biological activities are needed. Keywords: Rhus mysorensis; antioxidant; anti-inflammatory; anticoagulant; antiplatelet; liquid-liquid partition. INTRODUCTION xidative stress is viewed as an imbalance between the production of reactive oxygen species (ROS) and their elimination by protective mechanisms, which can lead to chronic inflammation. Oxidative stress can trigger increased generation of ROS and/or decreased levels of endogenous antioxidant enzymes including glutathione peroxidase (GpX), catalase, and superoxide dismutase (SOD) in many chronic and degenerative diseases including atherosclerosis, inflammatory diseases, ageing, diabetes mellitus, neurodegenerative disorders, drug toxicity, cancer, and others(1). Oxidative stress exacerbates the inflammatory responses and vice versa. Increased production of ROS enhances the inflammatory response by upregulating the genes related to immune and inflammatory cytokines through activation of the nuclear factor-κB, a redox-sensitive nuclear transcription factor. Antioxidants are bioactive compounds that reduce the pre-disposition to lipid peroxidation, oxidative stress, post- translational modification of proteins, and DNA damage through modulation of the oxidant– antioxidant levels in the body. Although several synthetic antioxidants, such as butylated hydroxyanisole (BHA) and butylated hydroxytolune (BHT) are available to control undesirable redox events are available, their usage is limited owing to their high cost, unavailability and unpleasant side effects associated with prolonged use. In view of these challenges, in recent years natural antioxidants have received greater attention, since they do not possess the side effects associated with their synthetic counterparts, are cheaper and ever-present O 724