International Journal of Applied Pharmaceutics ISSN - 0975 - 7058 Vol 11, Special Issue 5, 2019 ANTIOXIDANT AND FREE RADICAL SCAVENGING ACTIVITY OF HIBISCUS ACETOSELLA LEAVES EXTRACTS THISAKORN DUMRONGPHUTTIDECHA*, SURADWADEE THUNGMUNGMEE, WARACHATE KHOBJAI, NAKUNTWALAI WISIDSRI, SURACHAI TECHAEOI Department of Thai Traditional Medicine, Rajamangala University of Technology Thanyaburi, Pathumthani, Thailand. Email: Thisakorn_d@rmutt.ac.th Received: 11 January 2019, Revised and Accepted: 20 July 2019 ABSTRACT Objective: Hibiscus acetosella (HA) or Chaba Maple is native plant and cultivated in tropical western in Africa and north of America. The characteristics of HA are red to purple in stem, leaf, and flower that are the pigment of antioxidant compound as anthocyanins. Anthocyanins are in the group of flavonoid and have the role as functional foods which have several health benefits such as obesity and diabetes control, cardiovascular disease prevention, and others. Hence, the aim of this study was to investigate the antioxidant and free radical scavenging activity of HA leaves extracts. Materials and Methods: HA (Chaba Maple) leaves were collected in Pathum Thani province, Thailand, and were dried and extracted by maceration technique with three solvents – water, ethanol, and methanol. The antioxidant properties of extracts were carried out using 2,2’-azino-bis(3- ethylbenzothiazoline-6-sulfonic acid) (ABTS) radical scavenging assay and ferric reducing antioxidant power (FRAP) assay. The extracts were examined for their scavenging effect on hydroxyl radical (•OH) using hydroxyl radical scavenging assay and nitric oxide (NO) radical (•NO) using NO radical scavenging assay. Results: For ABTS, FRAP, and hydroxyl radical scavenging assay, ethanol extract showed the highest antioxidant property which the percentage inhibitions were 69.04%, 2381.84 µM/mg extract, and 62.88 mg/ml, respectively. For NO scavenging activity, methanol extract showed highest ability to scavenge NO which percentage inhibition was 101.28±0.73 mg/ml. Conclusion: The results of this study showed that ethanolic, methanolic, and water extract of HA leaves had scavenge and reducing antioxidant properties. Keywords: Hibiscus acetosella, Antioxidants, Radical scavenging activity, Hydroxyl radical, Nitric oxide radical. INTRODUCTION Aging is biological process in the body that is beyond the control of human. Aging occurs from the physical changes of cells and tissues and accumulative of wastes in the body together with the increasing of age which can lead to incidence rate of diseases and death [1]. In the present, the progress of medical technologies has more effect on aging process. However, aging is still undesirable. Theory of aging divides into two categories: Programmed theory and damage or error theory. Programmed theory identifies that aging is the process of biological timetable. The progress of aging is controlled by gene expression that can affect on maintenance, repair, and defense system of the body. Programmed theory divides into three subcategories [2]. 1. Programmed Longevity. This theory explains that aging is depend on the functions of genes. The declination of genes is correlative with the time of age 2. Neuroendocrine Theory. The pace of aging is controlled by biological clocks through hormones 3. Immunological Theory. The immune system is overtime declination which can lead to increase incidence in infectious diseases then aging occur and continues to death. Damage or error theory divides into 3 subcategories. 1. The Wear and Tear Theory. This theory was mentioned in the first time by Dr. August Weismann in 1882. Aging is the result of cells and tissues declination that are used by the process of body. 2. Free Radical Theory. The theory was presented by Dr. Gerschman in 1954 and was developed by Dr. Denham Harman [2]. Free radicals are unstable molecules that contain an unpaired electron. Free radicals are important role in the process of aging that is not imbalance between free radical and antioxidant. The high rate of free radical in the body leads to damage cells and tissues by oxidative reaction [3]. 3. Cross-linking theory. Cross-linking theory was presented by Johan Bjorksten in 1942. This theory explained that aging occurs from the accumulative of damage cross-linked proteins which damages cells and tissues [2]. Reactive oxygen species (ROS) is a group of free radicals that have high potent free radicals. They effect on human body both harmful and beneficial [4]. ROS is produced from metabolism in human body and exogenous factors. Overproduction of ROS is major result of oxidative stress that can damage nucleic acid bases, lipids, and proteins and leading to functional of cells and viability of cells. The highest potent free radicals in ROS are hydroxyl radicals (•OH). The high amount of ROS production in cells can stimulate the inflammatory process, secretion of chemotactic factors, growth factors, proteolytic enzymes, lipoxygenases, and cyclooxygenases. ROS and their metabolites can direct effect on cell injury and may stimulate the promoting of diseases [5]. Furthermore, nitric oxide (NO) radical (•NO) is the important free radical that can affect to human body. It is classified as free radical in reactive nitrogen species (RNS) when there is high amount of NO in human body, and it can associate with various carcinomas and inflammation conditions [6]. Hibiscus acetosella (HA) is a spicy of plant in Malvaceae family. It is native plant and cultivated in tropical western in Africa and north of America [7]. The characteristics of HA are red-purple in stem, leaf, and flower that are the pigment of antioxidant compound as anthocyanin [8]. Anthocyanin Research Article © 2019 The Authors. Published by Innovare Academic Sciences Pvt Ltd. This is an open access article under the CC BY license (http://creativecommons. org/licenses/by/4. 0/) DOI: http://dx.doi.org/10.22159/ijap.2019.v11s5.T0057 4 th International Conference on Pharmacy and Pharmaceutical Science (ICPPS) 2019