Oxygen radical antioxidant capacity (ORAC) and antibacterial properties of Melicope glabra bark extracts and isolated compounds
Melicope glabra (Blume) T. G. Hartley from the Rutaceae family is one of the richest sources of plant secondary metabolites, including coumarins and flavanoids. This study investigates the free radical scavenging and antibacterial activities of M. glabra and its isolated compounds. M. glabra ethyl a...
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| Format: | Article |
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Public Library of Science
2021
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| Online Access: | http://psasir.upm.edu.my/id/eprint/94492/ |
| _version_ | 1848862012615950336 |
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| author | Quek, Alexandra Mohd Zaini, Hafizah Kassim, Nur Kartinee Sulaiman, Fadzil Rukayadi, Yaya Ismail, Amin Zainal Abidin, Zamirah Awang, Khalijah |
| author_facet | Quek, Alexandra Mohd Zaini, Hafizah Kassim, Nur Kartinee Sulaiman, Fadzil Rukayadi, Yaya Ismail, Amin Zainal Abidin, Zamirah Awang, Khalijah |
| author_sort | Quek, Alexandra |
| building | UPM Institutional Repository |
| collection | Online Access |
| description | Melicope glabra (Blume) T. G. Hartley from the Rutaceae family is one of the richest sources of plant secondary metabolites, including coumarins and flavanoids. This study investigates the free radical scavenging and antibacterial activities of M. glabra and its isolated compounds. M. glabra ethyl acetate and methanol extracts were prepared using the cold maceration technique. The isolation of compounds was performed with column chromatography. The free radical scavenging activity of the extracts and isolated compounds were evaluated based on their oxygen radical absorbance capacity (ORAC) activities. The extracts and compounds were also subjected to antibacterial evaluation using bio-autographic and minimal inhibitory concentration (MIC) techniques against two oral pathogens, Enterococcus faecalis and Streptococcus mutans. Isolation of phytoconstituents from ethyl acetate extract successfully yielded quercetin 3, 5, 3’-trimethyl ether (1) and kumatakenin (2), while the isolation of the methanol extract resulted in scoparone (3), 6, 7, 8-trimethoxycoumarin (4), marmesin (5), glabranin (6), umbelliferone (7), scopoletin (8), and sesamin (9). The study is the first to isolate compound (1) from Rutaceae plants, and also the first to report the isolation of compounds (2–5) from M. glabra. The ORAC evaluation showed that the methanol extract is stronger than the ethyl acetate extract, while umbelliferone (7) exhibited the highest ORAC value of 24 965 μmolTE/g followed by glabranin (6), sesamin (9) and scopoletin (8). Ethyl acetate extract showed stronger antibacterial activity towards E. faecalis and S. mutans than the methanol extract with MIC values of 4166.7 ± 1443.4 μg/ml and 8303.3 ± 360.8 μg/ml respectively. Ethyl acetate extract inhibited E. faecalis growth, as shown by the lowest optical density value of 0.046 at a concentration of 5.0 mg/mL with a percentage inhibition of 95%. Among the isolated compounds tested, umbelliferone (7) and sesamin (9) exhibited promising antibacterial activity against S. mutans with both exhibiting MIC values of 208.3 ± 90.6 μg/ml. Findings from this study suggests M. glabra as a natural source of potent antioxidant and antibacterial agents. |
| first_indexed | 2025-11-15T13:10:15Z |
| format | Article |
| id | upm-94492 |
| institution | Universiti Putra Malaysia |
| institution_category | Local University |
| last_indexed | 2025-11-15T13:10:15Z |
| publishDate | 2021 |
| publisher | Public Library of Science |
| recordtype | eprints |
| repository_type | Digital Repository |
| spelling | upm-944922022-11-29T03:52:23Z http://psasir.upm.edu.my/id/eprint/94492/ Oxygen radical antioxidant capacity (ORAC) and antibacterial properties of Melicope glabra bark extracts and isolated compounds Quek, Alexandra Mohd Zaini, Hafizah Kassim, Nur Kartinee Sulaiman, Fadzil Rukayadi, Yaya Ismail, Amin Zainal Abidin, Zamirah Awang, Khalijah Melicope glabra (Blume) T. G. Hartley from the Rutaceae family is one of the richest sources of plant secondary metabolites, including coumarins and flavanoids. This study investigates the free radical scavenging and antibacterial activities of M. glabra and its isolated compounds. M. glabra ethyl acetate and methanol extracts were prepared using the cold maceration technique. The isolation of compounds was performed with column chromatography. The free radical scavenging activity of the extracts and isolated compounds were evaluated based on their oxygen radical absorbance capacity (ORAC) activities. The extracts and compounds were also subjected to antibacterial evaluation using bio-autographic and minimal inhibitory concentration (MIC) techniques against two oral pathogens, Enterococcus faecalis and Streptococcus mutans. Isolation of phytoconstituents from ethyl acetate extract successfully yielded quercetin 3, 5, 3’-trimethyl ether (1) and kumatakenin (2), while the isolation of the methanol extract resulted in scoparone (3), 6, 7, 8-trimethoxycoumarin (4), marmesin (5), glabranin (6), umbelliferone (7), scopoletin (8), and sesamin (9). The study is the first to isolate compound (1) from Rutaceae plants, and also the first to report the isolation of compounds (2–5) from M. glabra. The ORAC evaluation showed that the methanol extract is stronger than the ethyl acetate extract, while umbelliferone (7) exhibited the highest ORAC value of 24 965 μmolTE/g followed by glabranin (6), sesamin (9) and scopoletin (8). Ethyl acetate extract showed stronger antibacterial activity towards E. faecalis and S. mutans than the methanol extract with MIC values of 4166.7 ± 1443.4 μg/ml and 8303.3 ± 360.8 μg/ml respectively. Ethyl acetate extract inhibited E. faecalis growth, as shown by the lowest optical density value of 0.046 at a concentration of 5.0 mg/mL with a percentage inhibition of 95%. Among the isolated compounds tested, umbelliferone (7) and sesamin (9) exhibited promising antibacterial activity against S. mutans with both exhibiting MIC values of 208.3 ± 90.6 μg/ml. Findings from this study suggests M. glabra as a natural source of potent antioxidant and antibacterial agents. Public Library of Science 2021-05 Article PeerReviewed Quek, Alexandra and Mohd Zaini, Hafizah and Kassim, Nur Kartinee and Sulaiman, Fadzil and Rukayadi, Yaya and Ismail, Amin and Zainal Abidin, Zamirah and Awang, Khalijah (2021) Oxygen radical antioxidant capacity (ORAC) and antibacterial properties of Melicope glabra bark extracts and isolated compounds. PLoS One, 16 (5). art. no. e0251534. pp. 1-12. ISSN 1932-6203 https://journals.plos.org/plosone/article?id=10.1371/journal.pone.0251534 10.1371/journal.pone.0251534 |
| spellingShingle | Quek, Alexandra Mohd Zaini, Hafizah Kassim, Nur Kartinee Sulaiman, Fadzil Rukayadi, Yaya Ismail, Amin Zainal Abidin, Zamirah Awang, Khalijah Oxygen radical antioxidant capacity (ORAC) and antibacterial properties of Melicope glabra bark extracts and isolated compounds |
| title | Oxygen radical antioxidant capacity (ORAC) and antibacterial properties of Melicope glabra bark extracts and isolated compounds |
| title_full | Oxygen radical antioxidant capacity (ORAC) and antibacterial properties of Melicope glabra bark extracts and isolated compounds |
| title_fullStr | Oxygen radical antioxidant capacity (ORAC) and antibacterial properties of Melicope glabra bark extracts and isolated compounds |
| title_full_unstemmed | Oxygen radical antioxidant capacity (ORAC) and antibacterial properties of Melicope glabra bark extracts and isolated compounds |
| title_short | Oxygen radical antioxidant capacity (ORAC) and antibacterial properties of Melicope glabra bark extracts and isolated compounds |
| title_sort | oxygen radical antioxidant capacity (orac) and antibacterial properties of melicope glabra bark extracts and isolated compounds |
| url | http://psasir.upm.edu.my/id/eprint/94492/ http://psasir.upm.edu.my/id/eprint/94492/ http://psasir.upm.edu.my/id/eprint/94492/ |