Biology, Medicine, & Natural Product Chemistry ISSN 2089-6514 (paper) Volume 14, Number 1, April 2025 | Pages: 381-387 | DOI: 10.14421/biomedich.2025.141.381-387 ISSN 2540-9328 (online) Antioxidant Activity Test of Ethanol Extract from The Leaves and Bark of Kapur (Dryobalanops aromatica) from Distillation Solid Waste Using the DPPH and ABTS Methods Nur Maulida Sari1, Abdul Rasyid Zarta1, Heriad Daud Salusu1, Muhammad Fikri Hernandi1, Mohammad Ridho Ramadhan1, Nur Indah Pragaloka1, Rosalinda Kerawing1, Puspitasari Muis1, Siti Raihanah2, Jasmawati2, Farida Aryani3,* 1Department of Forest Product Processing; 3Department of Plantation Products Technology, Samarinda State Agriculture Polytechnic, Kampus Gunung Panjang Jalan Samratulangi, Samarinda 75131, East Kalimantan, Indonesia 2Midwifery Department, Ministry of Health Polytechnic, Samarinda, East Kalimantan, Indonesia. Corresponding author* faridaaryani@politanisamarinda.ac.id Manuscript received: 21 April, 2025. Revision accepted: 27 June, 2025. Published: 11 July, 2025. Abstract One of the endemic plants of East Kalimantan, kapur (Dryobalanops aromatica) belongs to the Dipterocarpaceae family and is typically used by the locals for essential oils. Solid waste is only used as a natural fertilizer, while the leaves and bark of Kapur (Dryobalanops aromatica) are often only used for the essential oil extracted. Research on solid waste from distilling kapur (Dryobalanops aromatica) has never been done. This investigation aimed to find the possible concentration of secondary metabolite chemicals and antioxidants in the ethanol extract of solid waste from distilling Kapur leaves and bark (Dryobalanops aromatica). The ethanol extract of Kapur leaves and bark (Dryobalanops aromatica) will undergo phytochemical testing utilizing a qualitative test method to ascertain the presence of secondary metabolite chemicals. The ethanol extract of Kapur leaves and bark (Dryobalanops aromatica) will be tested for antioxidant activity against DPPH and ABTS free radicals using a UV Spectrophotometer. The results of the phytochemical analysis showed that the ethanol extracts from the leaves and bark contained alkaloids, flavonoids and tannin. Triterpenoids are only found in the bark extracts, while saponins and steroids are only found in the leaves extracts. Antioxidant activity of Dryobalanops atomatica extract showed that ethanol extract displayed an ability to inhibit DPPH free radical in both the leaves and bark ethanol extracts, with percentages of 83.24% and 94.91% at 25 ppm concentration, respectively. Antioxidant activity of Dryobalanops atomatica extract showed that ethanol extract could inhibit DPPH free radical in the leaves and bark ethanol extracts, with percentages of 83.24% and 94.91% at 25 ppm concentration, respectively. Antioxidant activity of Dryobalanops atomatica extract showed that ethanol extract display an ability to inhibit ABTS free radical with a percentage of 84.23% at 50 ppm concentration in the leaves extracts, followed by 82.62% percentage of inhibition at 100 ppm concentration. According to the findings of the study, post-distillation solid waste from Dryobalanops aromatica leaves and bark had the potential to develop as a natural antioxidant. Keywords: ABTS; DPPH; Dryobalanops aromatica; Kalimantan Timur; Phytochemical. INTRODUCTION Kapur (Dryobalanops aromatica) is one of the endemic species from East Kalimantan that produces borneol (camphor) in both crystal and oil forms. This plant is also known to contain bioactive compounds that have effects as antifungal, antioxidant, toxic, and capable of inhibiting the spread of HIV (RITONGA et al. 2018; Wibowo et al. 2011). The indigenous population in Kutai Barat Regency continues to depend on species that are today considered uncommon in Indonesia for their livelihoods. According to several investigations, camphor oil of the kapur variety (Dryobalanops aromatica) has been described and is suitable for use in aromatherapy (Kamariyah et al. 2012; Kuspradini et al. 2016; Le et al. 2016; Yakubu et al. 2020). Phytochemical screening of methanol extract from the bark of kapur (Dryobalanops aromatica) contains flavonoids, saponins, tannins, and coumarin. Borneol in this tree can be applied externally for wounds, burns, rheumatic pain, and skin diseases (Pasaribu et al. 2014). The branches and leaves of this plant are employed orally for gum swelling, cholera, and breast pain. It has been reported that this plant contains terpenoids such as D-borneol, terpinen-4-ol, alpha- terpineol, alphapinene, and caryophyllene, which is known for its antimicrobial, cytotoxic, and anti- inflammatory activities (Ali 2014; Le et al. 2016). Numerous secondary metabolites, including terpenoids, lignans, flavonoids, saponins, secoiridoids, lactones, and alkaloids, are produced by plants and each have their distinct chemical structures and bioactivities. https://doi.org/10.14421/biomedich.2025.141.381-387 mailto:faridaaryani@politanisamarinda.ac.id 382 Biology, Medicine, & Natural Product Chemistry 14 (1), 2025: 381-387 The majority of significant pharmaceuticals are made from medicinal plants. With about 40,000 distinct plant species, including about 6000 medicinal plant species, Indonesia is the second-most biodiverse country in the world. As such, plants in Indonesia are predicted to be a great source of bioactive secondary metabolites for developing novel antiviral drugs (Aoki-Utsubo et al., 2023). One of the most physiologically varied groups of Indonesian plants is the Dipterocarpaceae family, which is found all around the nation. Oligostilbenes, phenolic compounds of resveratrol units ranging from monomers to octamers, are abundant in Dipterocarpaceae plants. From Dipterocarpaceae plants, resveratrol and its dimers (like ε-viniferin and laevifonol), trimers (like ampelopsin E, α-viniferin, and Malaysianol), and tetramers (like vaticaphenol B and C, hopeaphenol, and vaticaphenol B) have been identified. Because of their complex structures and wide range of biological functions, oligostilbenes have garnered much attention in recent decades. Nevertheless, little research has been done on their antiviral effectiveness (Abe et al. 2011; Ito 2020; ITO et al. 2000; Mattio et al. 2020). Antioxidants are known to stop chain reactions to stabilize free radicals. Free radicals become highly reactive compounds in body cells due to the chain reaction caused by unpaired electrons. This can lead to various long-lasting degenerative diseases that can cause tissue or cell damage (Lulan 2022). An antioxidant is a chemical substance that lessens a free radical's oxidation action by giving an electron to an unpaired free radical. Numerous chemicals found in herbs are potent antioxidants in clinical settings and can be employed as natural exogenous antioxidants (Amorati and Valgimigli 2018). Phenolic chemicals, which are secondary metabolites, are among the chemical substances that shield plant organs from oxidation. Consequently, the term "natural antioxidant" refers to the phenolic component. A phenolic molecule found in plants is known to have anti-inflammatory, anti-carcinogenic, anti-microbial, anti-allergic, and anti-mutagenic qualities in addition to its antioxidant action (Johan Sukweenadhi et al. 2020). Flavonoids are among the several phytochemicals with antioxidant properties. Numerous plant species contain flavonoids, which are polyphenolic chemicals that have been shown to support human health. Regular consumption of fruits and vegetables that contain flavonoids can lower the risk of cardiovascular disease. Numerous investigations have shown that flavonoids influence various pharmacological actions, such as enzyme inhibitors, anti-inflammatory, anti- cancer, and antioxidant agents (Ivey et al. 2017; Kim et al. 2018; Kumar et al. 2019). The strength of the evaluated Dryobalanops aromatica extract as a possible source of natural antioxidants for application in pharmaceutical, nutraceutical, and functional food compositions would undoubtedly be investigated with the aid of the current data. To further develop its uses in the food and pharmaceutical industries, more study is necessary to discover and purify the particular molecules that have antioxidant qualities. MATERIALS AND METHODS Study area The raw materials used in this study are the leaves and bark of Dryobalanops aromatica, obtained from Nyaribungan Village, Laham District, Mahakam Ulu Regency, East Kalimantan Province. The materials used in this study are DPPH (2,2-diphenyl-1-picrylhydrazyl), ABTS (2,2-azinobis-3-Ethylbenzothiazoline-6-Sulfonic Acid), 96% ethanol, acetone, 1-naphthol, bismuth (III) nitrate, H2SO4 (sulfuric acid), HCl (hydrochloric acid), CH3COOH (acetic acid), NaOH, lead acetate (Pb CH3COO2), potassium iodide, ascorbic acid (Vitamin C). The equipment used includes test tubes, Erlenmeyer flasks, glass funnels, beakers, 1000 µL micropipettes, 200 µL micropipettes, yellow tips, blue tips, cuvettes, rotary vacuum evaporators, and UV spectrophotometers. This research was conducted at the Wood Properties and Product Analysis Laboratory (SKAP), Department of Environmental and Forestry, State Agricultural Polytechnic of Samarinda. Procedures Maceration The raw materials, consisting of the leaves and bark of Dryobalanops aromatica, are first washed with running water to remove any adhering dirt, then dried in an air- conditioned room at a temperature of 20-25 ºC for 2-5 days until the samples are dry. The dried plant samples are then ground using a blender and are ready for maceration with ethanol solvent at room temperature and shaking on shaker about 48 hours. After filtration,the cride extract of the leaves and bark of Dryobalanops aromatica was evaporated using rotary vacuum evaporator at 38-40 ºC. Preliminary Phytochemical Analysis The ethanol extract of the leaves and bark of Dryobalanops aromatica was analyzed for secondary metabolites, including alkaloids, flavonoids, triterpenoids, steroids, tannins, and saponins, using qualitative testing methods (Sari et al. 2023). Alkaloids determination: About 5 ml of the ethanol extracts from leaves and bark of Dryobalanops aromatica were added of 2 ml Hydrochloride Acid, then 1 ml of Dragendorff solution was added. The color changes in the solution was indicated the presence of alkaloids. Flavonoids determination: About 1 ml of the ethanol extracts from leaves and bark of Dryobalanops aromatica were drops of 1% Sodium Hydroxide. The presence of yellow color at extracts solution and were Sari et al. – Antioxidant activity test of ethanol 383 colorless after addition of 1 % Hydrochloride Acid was indicated the presence of flavonoids. Triterpenoids determination: About 1 ml of the ethanol extracts from leaves and bark of Dryobalanops aromatica were drops of about 10 Acetic Acid Anhydride and 2 drops of Sulfuric Acid, sequentially. The red or purple color changes in the solution was indicated the presence of triterpenoids. Steroids determination: About 1 ml of the ethanol extracts from leaves and bark of Dryobalanops aromatica were drops about 10 Acetic Acid Anhydride and 2 drops of Sulfuric Acid, sequentially. The green or blue color changes in the solution was indicated the presence of steroids. Tannins determination: About 10 ml of the ethanol extracts from leaves and bark of Dryobalanops aromatica were added 1 % Lead II Acetate. The yellow precipitate reaction at solution was indicated the presence of tannin. Saponins determination: About 10 ml of hot distilled water were added 1 ml of of the nethanol extracts from leaves and bark of Dryobalanops aromatica. The solution then cooled and shaken vigorously (10 seconds). A stable froth upon standing for 10 minutes after added 1 drops of Hydrochloride Acid 2N was indicated the presence of saponins. Antioxidant Assay of DPPH Antioxidant testing was conducted with 5 test sample concentrations into 6.25 ppm, 12.5 ppm, 25 ppm, 50 ppm, and 100 ppm. About 3 mg of the extract was weighed, then dissolved in 1 ml of ethanol solvent, and subsequently, a concentration dilution for testing was performed. 33 µl of the sample was placed into a test tube and 467 µl of ethanol was added. After homogenization, 500 µl of the DPPH (2,2-diphenyl-1- picrylhydrazyl) free radical solution was added (Sari et al., 2023). The mixing of the test sample is sufficient when it reaches a volume of 1000 µl (1 ml). The test sample was then incubated in a low-light room for 20 minutes at room temperature of 27-30 ºC. Antioxidant activity using DPPH decolorization was measured using a UV-Spectrophotometer at a wavelength of 517 nm. The testing was conducted in the triplicate repetitions. The percentage of DPPH free radicals is calculated using the formula: 𝐼𝑛ℎ𝑖𝑏𝑖𝑡𝑜𝑟𝑦 𝑜𝑓 𝐷𝑃𝑃𝐻 𝑅𝑎𝑑𝑖𝑐𝑎𝑙 (%) = 𝛥𝑘𝑜𝑛𝑡𝑟𝑜𝑙 − 𝛥𝑠𝑎𝑚𝑝𝑒𝑙 𝛥𝑘𝑜𝑛𝑡𝑟𝑜𝑙 × 100 Antioxidant Assay of ABTS Antioxidant testing was conducted with 5 test sample concentrations into 6.25 ppm, 12.5 ppm, 25 ppm, 50 ppm, and 100 ppm. About 5 mg of extract was weighed, then dissolved in 1 ml of methanol solvent, and then a dilution of the test concentration was performed. 50 µl of the sample was placed into a test tube and 450 µl of ethanol was added. After homogenization, 500 µl of the ABTS free radical solution (2,2-azinobis-3- Ethylbenzothiazoline-6-Sulfonic Acid) was added with slight modification (Sari et al. 2024). The mixing of the test sample is completed when it reaches a volume of 1000 µl (1 ml). The test sample was then incubated in a low-light room for 5 minutes at room temperature of 27- 30 ºC. Antioxidant activity using ABTS decolorization was measured using a UV-Spectrophotometer at a wavelength of 734 nm. The testing was conducted in the triplicate repetitions. The percentage of DPPH free radicals is calculated using the formula: 𝐼𝑛ℎ𝑖𝑏𝑖𝑡𝑜𝑟𝑦 𝑜𝑓 𝐴𝐵𝑇𝑆𝑅𝑎𝑑𝑖𝑐𝑎𝑙 (%) = 𝛥𝑘𝑜𝑛𝑡𝑟𝑜𝑙 − 𝛥𝑠𝑎𝑚𝑝𝑒𝑙 𝛥𝑘𝑜𝑛𝑡𝑟𝑜𝑙 × 100 RESULTS AND DISCUSSION Plant Extracts Samples of leaves and bark of the kapur tree (Dryobalanops aromatica) have been macerated using ethanol at room temperature (Table 1). The extract is calculated based on the dry plant sample’s weight divided by the sample’s initial weight. Table 1. Percentage of ethanol extract from the leaves and bark of kapur (Dryobalanops aromatica). Plants parts Yield of Extracts (g) Percentage (%) Leaves 2.87 9.89 Bark 16.36 19.05 Note: Percentage is calculated based on the weight of the dry sample. Based on the results obtained, the weight of bark parts is 16.36 grams from a total of 85.91 grams of the extracted sample. Meanwhile, the extract of leaves parts weight is 2.87 grams from a total of 29.03 grams of the extracted sample. This also affect the yield produced by the samples, where the leaves parts have a yield of 9.89% and the bark parts has a yield of 19.05%. A solvent with a high extraction rate, ethanol is readily available, effective, and safe for the environment (Chen, Xiao, and Pang 2020; Fan et al. 2020; Hakim and Saputri 2020). Ethanol is a polar, multipurpose solvent that works well for first extraction. The ability of ethanol solvent to permeate cell wall components allows it to perform cell diffusion and more quickly draw in bioactive substances (Prayitno and Rahim 2020; Yulianti et al. 2021). Phytochemical Analysis Ethanol extracts from the leaves and bark of the kapur tree (Dryobalanops aromatica) showed the presence of secondary metabolite compounds as presented in Table 2. Alkaloids, phenolics, flavonoids, tannins, quinones, saponins, and terpenoids are among the chemical 384 Biology, Medicine, & Natural Product Chemistry 14 (1), 2025: 381-387 components contributing to bioactivity as medicinal ingredients. Alkaloids serve as plant defenses against pathogens and herbivores as well as stimulants of the central nervous system, while tannins have been used as antidiarrheals and antihemorrhagic. Phenolics and flavonoids are classified as antioxidants and have been shown to have numerous health benefits, as well as the ability to prevent and cure several diseases (Mousavi, Salleh, and Murugaiyah 2018; Praptiwi et al. 2020; Tungmunnithum et al. 2018). Table 2. Phytochemical analysis of ethanol extract from the leaves and bark of kapur (Dryobalanops aromatica). No Compounds Presences Leaves Bark 1 Alkaloids + + 2 Flavonoids + + 3 Triterpenoids - + 4 Tannin + + 5 Saponins + - 6 Steroids + - Antioxidant Test using the DPPH Method The ability of the ethanol extract of the leaves and bark of the kapur tree (Dryobalanops aromatica) to inhibit DPPH free radicals was demonstrated by antioxidant testing; the percentages of inhibition for the leaves and bark ranged from 27.30 to 83.24% and 82.32 to 94.91%, respectively. At a dosage of 25 ppm, the greatest inhibition was seen in the leaves and bark ethanol extracts, with percentages of 83.24% and 94.91%, respectively (Figure 1). Figure 1. Inhibitory activity of ethanol extract of leaves and bark of the kapur tree (Dryobalanops aromatica) against DPPH free radicals. Studies on the active ingredients in Dryobalanops sp. plant essential oils have revealed that α-pinene compounds and monoterpene derivatives may operate as natural antioxidants (Aswandi and Kholibrina 2020). Antioxidant qualities are known to be present in phenolic compounds. The oxidative activities of these substances are typically exhibited by many modes of action, such as metal ion chelation, hydrogen-donating antioxidant, free radical scavenger, and singlet oxygen quencher (Che Rozenan et al. 2021). This plant's potential for development as a natural antioxidant that can suppress DPPH free radicals is further demonstrated by alkaloids, flavonoids, and tannins in this plant extract. Antioxidant test using ABTS Method Inhibition percentages for the ethanol extract leaves and bark of the kapur tree (Dryobalanops aromatica) were from 27.84 to 81.62% in the leaves and 11.31 to 82.62% in the bark, respectively, indicating the extract's capacity to inhibit ABTS free radicals. The highest inhibition was observed in the leaves part of ethanol extracts with 84.23% at 50 ppm concentration, followed by the bark parts at 100 ppm concentration with a percentage of 82.62% inhibition (Figure 2). 0,00 97,03 27,30 63,22 83,24 81,51 75,48 0,00 97,57 82,32 94,52 94,91 94,68 93,66 0,00 20,00 40,00 60,00 80,00 100,00 120,00 Control Ascorbic Acid 25 ppm 6,25 12,5 25 50 100 D P P H I n h ib it io n ( % ) Extract Consentration (ppm) DPPH Antioxidant of Dryobalanops aromatica Leaves Bark Sari et al. – Antioxidant activity test of ethanol 385 Figure 2. Inhibitory activity of ethanol extract of leaves and bark of the kapur tree (Dryobalanops aromatica) against ABTS free radicals. Based on previous study, the crude extract of methanol from the leaves and bark of Dryobalanops aromatica showed the highest antioxidant activity with a percentage of 93.86% and 93.77%, respectively. The leaves and bark of Dryobalanops aromatica also have the highest ability in total phenolic content by 1084.13 and 972.71 GAE (Che Rozenan et al. 2021). Dryobalanops aromatica genus was reported to be a source of resveratrol oligimers such as trans-3,4’,5- trihydroxystilbene and bergenin, which has many bioactive benefits such as antioxidants and antidiabetic activities (Wibowo et al. 2012, 2014). Research about GCMS from methanol extract of Dryobalanops aromatica found five similiar compounds such as performic acid, acetic acid, decane, glycerine and propanoic acid (Chang and Othman 2014). Meanwhile, these compounds suggested that both leaves and bark extracts contributed to the antioxidant and antidiabetic activities of Dryobalanops aromatica (Heinonen‐Tanski and Miettinen 2010). CONCLUSIONS One of the endemics of East Kalimantan, Dryobalanops aromatica, belongs to the Dipterocarpaceae genus and has been researched for its antioxidant properties. Using DPPH and ABTS free radicals, the study's findings demonstrated that post-distillation solid waste from the leaves and bark extracted with ethanol gave useful information on the amount of active chemicals and antioxidants. This genus still requires much research, particularly to identify the active ingredients in Dryobalanops aromatica. The leaves and bark of Dryobalanops aromatica can be extracted and used as a natural antioxidant in the medical field, according to the study's findings. Acknowledgements: This research was funded by the Samarinda State Agricultural Polytechnic (Politani Samarinda) through Penelitian Terapan Dosen Scheme (Lecturer Research Internal Grans) 2024 under contract number 141/PL21.G/PG/2024. We would also like to thank all parties involved in this research, who have been willing to provide information and plant specimens for research. Authors’ Contributions: In this study, Nur Maulida Sari designed the study, supervised all processes, and wrote the manuscript. Abdul Rasyid Zarta and Heriad Daud Salusu conducted observations and sample collection. Muhammad Fikri Hernandi supervised the samples and material preparation. Mohammad Ridho Ramadhan, Nur Indah Pragaloka, Rosalinda Kerawing and Pustitasari Muis supervised the research data analysis and manuscript. Siti Raihanah and Jasmawati supervised the research data analysis and manuscript writing. Farida Aryani supervised all research data analysis and manuscript writing. Competing Interests: There is no conflict of interest in this research. REFERENCES Abe, Naohito, Tetsuro Ito, Masayoshi Oyama, Ryuichi Sawa, Yoshikazu Takahashi, and Munekazu Iinuma. 2011. “Resveratrol Derivatives from Vatica Albiramis.” Chemical and Pharmaceutical Bulletin 59(4):452–57. doi: 10.1248/cpb.59.452. Ali, Muhammad. 2014. “Therapeutic Flora in Holy Quran.” African Journal of History and Culture. doi: 10.5897/AJHC2014.0188. Amorati, Riccardo, and Luca Valgimigli. 2018. “Methods To Measure the Antioxidant Activity of Phytochemicals and Plant 0,00 86,13 27,84 51,98 63,42 84,23 81,62 0,00 85,34 11,31 47,78 54,84 82,08 82,62 0,00 10,00 20,00 30,00 40,00 50,00 60,00 70,00 80,00 90,00 100,00 Control Ascorbic Acid 25 ppm 6,25 12,5 25 50 100 D P P H I n h ib it io n ( % ) Extract Concentration (ppm) ABTS Antioxidant of Dryobalanops aromatica Leaves Bark 386 Biology, Medicine, & Natural Product Chemistry 14 (1), 2025: 381-387 Extracts.” Journal of Agricultural and Food Chemistry 66(13):3324–29. doi: 10.1021/acs.jafc.8b01079. Aoki-Utsubo, Chie, Muhammad Hanafi, Destia Tri Armanti, Hiroyuki Fuchino, Nobuo Kawahara, Sri Hartati, Aty Widyawaruyanti, Pratiwi Sudarmono, Masanori Kameoka, and Hak Hotta. 2023. “Identification of an Oligostilbene, Vaticanol B, from <I>Dryobalanops Aromatica</I> Leaves as an Antiviral Compound against the Hepatitis C Virus.” Biological and Pharmaceutical Bulletin 46(8):b23-00086. doi: 10.1248/bpb.b23-00086. Aswandi, Aswandi, and Cut Rizlani Kholibrina. 2020. “Potensi Minyak Atsiri Kamfer Sumatera (Dryobalanops Aromatica Gaertn.) Untuk Bahan Baku Obat Herbal.” Jurnal Farmasi Udayana 171. doi: 10.24843/JFU.2020.v09.i03.p05. Chang, Sui Kiat, and Azizah Othman. 2014. “Phenolics, Flavonoids Content and Antioxidant Activities of 4 Malaysian Herbal Plants.” International Food Research Journal 21:759– 66. Che Rozenan, Nooraqilah, Nor Hisam Zamakshshari, Kok Hoong Leong, Najihah Mohd Hashim, Khadher Ahmad, Munirah Abd Razzak, Zulkifli Mohd Yusof, Khalijah Awang, Abd Aziz Ismail, and Rozana Othman. 2021. “Biological and Analytical Investigations of Alpha-Glucosidase Inhibitory and Anti- Oxidant Activities on Selected Malaysian Medicinal Plants.” Sains Malaysiana 50(9):2625–40. doi: 10.17576/jsm-2021- 5009-11. Chen, Haiyan, Han Xiao, and Jiwei Pang. 2020. “Parameter Optimization and Potential Bioactivity Evaluation of a Betulin Extract from White Birch Bark.” Plants 9(3):392. doi: 10.3390/plants9030392. Fan, Sanhong, Gege Yang, Jinhua Zhang, Jiani Li, and Baoqing Bai. 2020. “Optimization of Ultrasound-Assisted Extraction Using Response Surface Methodology for Simultaneous Quantitation of Six Flavonoids in Flos Sophorae Immaturus and Antioxidant Activity.” Molecules 25(8):1767. doi: 10.3390/molecules25081767. Hakim, Ali Rakhman, and Rina Saputri. 2020. “Narrative Review: Optimasi Etanol Sebagai Pelarut Senyawa Flavonoid Dan Fenolik.” Jurnal Surya Medika 6(1):177–80. doi: 10.33084/jsm.v6i1.1641. Heinonen‐Tanski, Helvi, and Harri Miettinen. 2010. “Performic Acid as A Potential Disinfectant at Low Temperature.” Journal of Food Process Engineering 33(6):1159–72. doi: 10.1111/j.1745-4530.2008.00332.x. Ito, Tetsuro. 2020. “Resveratrol Oligomer Structure in Dipterocarpaceaeous Plants.” Journal of Natural Medicines 74(4):619–37. doi: 10.1007/s11418-020-01412-x. ITO, Tetsuro, Toshiyuki TANAKA, Yoshimi IDO, Ken-ichi NAKAYA, Munekazu IINUMA, and Soedarsono RISWAN. 2000. “Stilbenoids Isolated from Stem Bark of Shorea Hemsleyana.” Chemical and Pharmaceutical Bulletin 48(7):1001–5. doi: 10.1248/cpb.48.1001. Ivey, Kerry L., Majken K. Jensen, Jonathan M. Hodgson, A. Heather Eliassen, Aedín Cassidy, and Eric B. Rimm. 2017. “Association of Flavonoid-Rich Foods and Flavonoids with Risk of All-Cause Mortality.” British Journal of Nutrition 117(10):1470–77. doi: 10.1017/S0007114517001325. Johan Sukweenadhi, Oeke Yunita, Finna Setiawan, KARTINI, Maya Theresa Siagian, Nggreyni Pratiwi Danduru, and Christina Avanti. 2020. “Antioxidant Activity Screening of Seven Indonesian Herbal Extract.” Biodiversitas Journal of Biological Diversity 21(5). doi: 10.13057/biodiv/d210532. Kamariyah, A. S., T. Ozek, B. Demirci, and K. H. C. Baser. 2012. “Chemical Composition of Leaf and Seed Oils of Dryobalanops Aromatica Gaertn. (Dipterocarpaceae).” ASEAN Journal on Science and Technology for Development 29(2):105. doi: 10.29037/ajstd.57. Kim, Yu-Jin, Sung Chul Joo, Jianxin Shi, Chaoyang Hu, Sheng Quan, Jianping Hu, Johan Sukweenadhi, Padmanaban Mohanan, Deok-Chun Yang, and Dabing Zhang. 2018. “Metabolic Dynamics and Physiological Adaptation of Panax Ginseng during Development.” Plant Cell Reports 37(3):393– 410. doi: 10.1007/s00299-017-2236-7. Kumar, Dinesh, Lallan Ram, M. S. Ladaniya, Archana Khadse, and Sunil Kumar. 2019. “Environmental Impact on Biochemical Parameters during Developmental Stages of Citrus Fruit.” Indian Journal of Horticulture 76(2):253. doi: 10.5958/0974-0112.2019.00039.2. Kuspradini, Harlinda, Agmi Sinta Putri, Edi Sukaton, and Tohru Mitsunaga. 2016. “Bioactivity of Essential Oils from Leaves of Dryobalanops Lanceolata, Cinnamomum Burmannii, Cananga Odorata, and Scorodocarpus Borneensis.” Agriculture and Agricultural Science Procedia 9:411–18. doi: 10.1016/j.aaspro.2016.02.157. Le, Tian-Xin, Anthony Siong-Hock Ho, Siau-Hui Mah, Tin-Wui Wong, Hean-Chooi Ong, Patrick Heng-Meng Loh, and Yang- Mooi Lim. 2016. “Determination of Borneol and Other Chemical Compounds of Essential Oil of <I>Dryobalanops Aromatica</I> Exudate from Malaysia.” Tropical Journal of Pharmaceutical Research 15(6):1293. doi: 10.4314/tjpr.v15i6.23. Lulan, Theodore Yehezkiel Kristoferson. 2022. “Antioxidant and Antibacterial Activity of The Stem Bark Extract of Sterculia Foetida L.” Jurnal Sains Dan Terapan Kimia 16(2):131. doi: 10.20527/jstk.v16i2.12040. Mattio, Luce M., Giorgia Catinella, Andrea Pinto, and Sabrina Dallavalle. 2020. “Natural and Nature-Inspired Stilbenoids as Antiviral Agents.” European Journal of Medicinal Chemistry 202:112541. doi: 10.1016/j.ejmech.2020.112541. Mousavi, Leila, Rabeta Mohd Salleh, and Vikneswaran Murugaiyah. 2018. “Phytochemical and Bioactive Compounds Identification of Ocimum Tenuiflorum Leaves of Methanol Extract and Its Fraction with an Anti-Diabetic Potential.” International Journal of Food Properties 21(1):2390–99. doi: 10.1080/10942912.2018.1508161. Pasaribu, Gunawan, Gusmailina Gusmailina, Sri Komarayati, Zulnely Zulnely, and Erik Dahlian. 2014. “Analisis Senyawa Kimia Dryobalanops Aromatica.” Jurnal Penelitian Hasil Hutan 32(1):21–26. doi: 10.20886/jphh.2014.32.1.21-26. Praptiwi, Praptiwi, Dewi Wulansari, Ahmad Fahoni, Noto Harnoto, Rossi Novita, Alfridsyah, and Andria Agusta. 2020. “Phytochemical Screening, Antibacterial and Antioxidant Assessment of Leuconotis Eugenifolia Leaf Extract.” Nusantara Bioscience 12(1). doi: 10.13057/nusbiosci/n120114. Prayitno, Sutrisno Adi, and Andi Rahmad Rahim. 2020. “The Comparison of Extracts (Ethanol And Aquos Solvents) Muntingia Calabura Leaves on Total Phenol, Flavonid And Antioxidant (Ic50) Properties.” Kontribusia (Research Dissemination for Community Development) 3(2):319. doi: 10.30587/kontribusia.v3i2.1451. Ritonga, Faujiah Nurhasanah, Fifi Gus Dwiyanti, Cecep Kusmana, Ulfah Juniarti Siregar, and Iskandar Zulkarnaen Siregar. 2018. “Population Genetics and Ecology of Sumatran Camphor (Dryobalanops Aromatica) in Natural and Community-Owned Sari et al. – Antioxidant activity test of ethanol 387 Forests in Indonesia.” Biodiversitas Journal of Biological Diversity 19(6):2175–82. doi: 10.13057/biodiv/d190625. Sari, Kartika, Anton Rahmadi, Miftakhur Rohmah, Bernatal Saragih, and Iddris Salam. 2024. “Antioxidant Activities (DPPH and ABTS Method) from Extract of Bangle Rhizome (Zingiber Cassumunar) Using Different Method of Extraction.” AcTion: Aceh Nutrition Journal 9(1):110. doi: 10.30867/action.v9i1.1531. Sari, Nur Maulida, Farida Aryani, Wartomo Wartomo, Muhammad Fikri Hernandi, Erna Rositah, and Joko Prayitno. 2023. “Phytochemical and Antioxidant Activity of Blumea Balsamifera and Cordyline Fruticosa Based on Ethnopharmacology Knowledge of Muara Tae Tribe, East Kalimantan.” Biology, Medicine, & Natural Product Chemistry 12(1):273–80. doi: 10.14421/biomedich.2023.121.273-280. Tungmunnithum, Duangjai, Areeya Thongboonyou, Apinan Pholboon, and Aujana Yangsabai. 2018. “Flavonoids and Other Phenolic Compounds from Medicinal Plants for Pharmaceutical and Medical Aspects: An Overview.” Medicines 5(3):93. doi: 10.3390/medicines5030093. Wibowo, A., N. Ahmat, A. S. Hamzah, N. H. Ismail, R. Ahmad, and F. M. Jaafar. 2012. “Resveratrol Oligomers from the Stem Bark of Dryobalanops Aromatica.” Biochemical Systematics and Ecology 40:62–64. doi: 10.1016/j.bse.2011.09.013. Wibowo, A., N. Ahmat, A. S. Hamzah, F. A. Latif, J. S. Norrizah, H. Y. Khong, and H. Takayama. 2014. “Identification and Biological Activity of Secondary Metabolites from Dryobalanops Beccarii.” Phytochemistry Letters 9:117–22. doi: 10.1016/j.phytol.2014.05.001. Wibowo, A., N. Ahmat, A. S. Hamzah, A. S. Sufian, N. H. Ismail, R. Ahmad, F. M. Jaafar, and H. Takayama. 2011. “Malaysianol A, a New Trimer Resveratrol Oligomer from the Stem Bark of Dryobalanops Aromatica.” Fitoterapia 82(4):676–81. doi: 10.1016/j.fitote.2011.02.006. Yakubu, Saraya A., Afidah Abdul Rahim, Mohamad Nurul Azmi, Khalijah Awang, and M. Hazwan Hussin. 2020. “Comparative Evaluations of Antioxidant Potentials of Dryobalanops Aromatica Tree Bark Extracts as Green Corrosion Inhibitors of Mild Steel in Hydrochloric Acid.” Materials Research Express 6(12):1265c4. doi: 10.1088/2053-1591/ab62f9. Yulianti, Wina, Gilang Ayuningtyas, Rina Martini, and Ika Resmeiliana. 2021. “Pengaruh Metode Ekstraksi dan Polaritas Pelarut Terhadap Kadar Fenolik Total Daun Kersen (Muntingia Calabura L).” Jurnal Sains Terapan 10(2):41–49. doi: 10.29244/jstsv.10.2.41-49. THIS PAGE INTENTIONALLY LEFT BLANK