Special Issue (May) Online - 2455-3891 Print - 0974-2441 II-Indonesian Conference on Clinical Pharmacy ANTIOXIDANT ACTIVITY FROM TEN SPECIES OF MYRTACEAE ZELIKA MEGA RAMADHANIA 1 *, MUHAMAD INSANU 2 , NENI SRI GUNARTI 3 , KOMAR RUSLAN WIRASUTISNA 2 , SUKRASNO SUKRASNO 2 , RIKA HARTATI 2 1 Department of Pharmaceutical of Biology, Faculty of Pharmacy, Universitas Padjadjaran, West Java, Indonesia. 2 Department of Pharmaceutical of Biology, School of Pharmacy, Bandung Institute of Technology, West Java, Indonesia. 3 Department of Pharmaceutical Biology, Faculty of Pharmacy, Buana Perjuangan University, West Java, Indonesia. Email: zelika.mega@unpad@ac.id Received: 24 September 2016, Revised and Accepted: 30 January 2017 ABSTRACT Objective: Antioxidants are compounds that can inhibit free radical reactivity. They become very interesting to be observed because they can prevent some diseases such as goat arthritis, cancer, cardiovascular disease, Alzheimer’s disease, and macular degeneration. Since Indonesia is rich for its biodiversity, there are a lot of plants that have potential to be developed as new alternative antioxidants. The aim of this research was to evaluate antioxidant activity from 10 species of Myrtaceae (Syzygium cumini, Syzygium samarangense, Syzygium aqueum, Syzygium aromaticum, Syzygium polyanthum, Syzygium jambos, Syzygium malaccense, Psidium guajava, Eucalyptus deglupta, and Melaleuca leucadendra). Methods: Continuous extraction with Soxhlet apparatus was selected as extraction method. Three solvents (n-hexane, ethyl acetate, and methanol) with different polarity were used in this process. 2,2-diphenyl-1-picrylhydrazyl radical scavenging activity was used to evaluate antioxidant activity with ascorbic acid as a standard drug. Results: Based on the experiments, methanol extracts showed higher activity than other extracts with their inhibitory concentration 50% (IC 50 ) was below than 25 µg/ml. The lowest IC 50 was exhibited by methanol extract of S. jambos, which was 7.8 µg/ml. Conclusion: It can be concluded that S. jambos is potential to be developed as a new alternative antioxidant. Keywords: Antioxidants, Eucalyptus, Syzygium, Melaleuca, Psidium, 2,2-diphenyl-1-picrylhydrazyl. INTRODUCTION Antioxidants are substances that may protect cells from the damage caused by unstable molecules (free radicals) [1]. Cell damage caused by free radicals appears to be a major contributor to aging and to degenerative diseases of cancer, cardiovascular diseases, cataracts, immune system decline, and brain dysfunction [2]. In general, free radicals have been implicated in the pathogenesis of at least 50 diseases [3]. Several studies have shown that plant-derived antioxidant nutraceuticals scavenge free radicals and modulate oxidative stress-related degenerative effects [4-6]. Eucalyptus species from Myrtaceae family has been widely explored on their various pharmacological activities such as analgesic, antifungal, anti-inflammatory, antibacterial, antidiabetic, antioxidative, antiviral, antitumor, antihistaminic, anticancer, cytochrome p450 inhibitor, and hepatoprotective properties [7]. The previous studies on fruits from plants of Myrtaceae family showed that phenolic compounds, such as ellagic acid, rutin, and quercetin, contributed to antioxidant activity. They could be found in Eugenia brasiliensis, Melaleuca cauliflora, Melaleuca vexator, Syzygium curranii, Syzygium cumini, Syzygium malaccense, Syzygium samarangense Syzygium jambos, and Psidium guajava [8,9]. Previous studies confirmed that seeds of Syzygium aromaticum have a number of polyphenols including ellagic acid (9.08 mg/kg), ellagic acid derivative (3.46 mg/kg), gallic acid (28.55 mg/kg), and quercetin glucoside (3.53 mg/kg) [10]. Eugenol of S. aromaticum has suppressive effects on arthritic rats [11]. Part of Syzygium aqueum (fruit) has been confirmed to have 4.1 mg/100 g of ascorbic acid content, 35.0 mg/100 g of total phenol content, and 31.0 mg/100 g of ascorbic acid equivalent antioxidant activity, meaning have mild antioxidant activity [12]. Until now, the information regarding antioxidant activity from the leaves of Myrtaceae was still limited. The aim of this study was to observe antioxidant activity from the leaves of Eucalyptus deglupta, S. mallaccenses, S. samarangense, P. guajava, S. cumini, S. aquaeum, S. aromaticum, Melaleuca leucadendra, and S. polyanthum. METHODS Plants material The leaves of S. jambos, E. deglupta, S. mallaccenses, S. samarangense, and S. cumini were collected from Indonesian Institute of Sciences, Center for Plant Conservation - Bogor Botanical Gardens (Bogor, West Java, Indonesia) and the leaves of P. guajava, S. aqueum, S. aromaticum, M. leucadendra, and S. polyanthum were collected from various places in Bandung, West Java, Indonesia. Extraction The dried plant material was powdered using a grinder. It was weighed (300 g) and extracted with various solvents, which had gradual polarity such as hexane, ethyl acetate, and methanol using Soxhlet apparatus. The solvents were evaporated under reduced pressure using a rotary evaporator, and a greenish-black colored sticky residue would be obtained. 2,2-diphenyl-1-picrylhydrazyl (DPPH) radical scavenging assay The antioxidant activity of the plant’s extracts and preparation of DPPH solution were adopted from Blois [13] by making some modifications. The diluted working solutions of the test extracts and DPPH were prepared in methanol. Each extract (various concentrations) was mixed Research Article © 2017 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/ajpcr.2017.v10s2.19470