Isolation and identification of radical scavenging and tyrosinase inhibition of polyphenols from tibouchina semidecandra L.
Phytochemical and bioactivity studies of the leaves and stem barks of Tibouchina semidecandra L. have been carried out. The ethyl acetate extract of the leaves yielded four flavonoid compounds, identified as quercetin, quercetin 3-O-a-l-(2''-O-acetyl) arabinofuranoside, avicularin, and que...
| Main Authors: | , , |
|---|---|
| Format: | Article |
| Published: |
American Chemical Society
2010
|
| Subjects: |
| _version_ | 1796856178971508736 |
|---|---|
| author | Mohd. Sirat, Hasnah Rezali, Mohamad Fazlin Ujang, Zanariah |
| author_facet | Mohd. Sirat, Hasnah Rezali, Mohamad Fazlin Ujang, Zanariah |
| author_sort | Mohd. Sirat, Hasnah |
| collection | ePrints |
| description | Phytochemical and bioactivity studies of the leaves and stem barks of Tibouchina semidecandra L. have been carried out. The ethyl acetate extract of the leaves yielded four flavonoid compounds, identified as quercetin, quercetin 3-O-a-l-(2''-O-acetyl) arabinofuranoside, avicularin, and quercitrin, while the stem barks gave one ellagitannin, identified as 3,3'-O-dimethyl ellagic acid 4-O-a-l-rhamnopyranoside. Evaluation of the antioxidative activity on the crude extracts and pure compounds by electron spin resonance (ESR) and ultraviolet-visible (UV-vis) spectrophotometric assays showed that the pure isolated polyphenols and the EtOAc extract possessed strong antioxidative capabilities. Quercetin was found to be the most active radical scavenger in DPPH-UV and ESR methods with SC(50) values of 0.7 µM ± 1.4 and 0.7 µM ± 0.6 µM, respectively, in the antioxidant assay. A combination of quercetin and quercitrin was tested for synergistic antioxidative capacity;, however, there was no significant improvement observed. Quercetin also exhibited strong antityrosinase activity with a percent inhibition of 95.0% equivalent to the positive control, kojic acid, in the tyrosinase inhibition assay. |
| first_indexed | 2024-03-05T18:39:37Z |
| format | Article |
| id | utm.eprints-26297 |
| institution | Universiti Teknologi Malaysia - ePrints |
| last_indexed | 2024-03-05T18:39:37Z |
| publishDate | 2010 |
| publisher | American Chemical Society |
| record_format | dspace |
| spelling | utm.eprints-262972018-11-09T08:07:47Z http://eprints.utm.my/26297/ Isolation and identification of radical scavenging and tyrosinase inhibition of polyphenols from tibouchina semidecandra L. Mohd. Sirat, Hasnah Rezali, Mohamad Fazlin Ujang, Zanariah Q Science Phytochemical and bioactivity studies of the leaves and stem barks of Tibouchina semidecandra L. have been carried out. The ethyl acetate extract of the leaves yielded four flavonoid compounds, identified as quercetin, quercetin 3-O-a-l-(2''-O-acetyl) arabinofuranoside, avicularin, and quercitrin, while the stem barks gave one ellagitannin, identified as 3,3'-O-dimethyl ellagic acid 4-O-a-l-rhamnopyranoside. Evaluation of the antioxidative activity on the crude extracts and pure compounds by electron spin resonance (ESR) and ultraviolet-visible (UV-vis) spectrophotometric assays showed that the pure isolated polyphenols and the EtOAc extract possessed strong antioxidative capabilities. Quercetin was found to be the most active radical scavenger in DPPH-UV and ESR methods with SC(50) values of 0.7 µM ± 1.4 and 0.7 µM ± 0.6 µM, respectively, in the antioxidant assay. A combination of quercetin and quercitrin was tested for synergistic antioxidative capacity;, however, there was no significant improvement observed. Quercetin also exhibited strong antityrosinase activity with a percent inhibition of 95.0% equivalent to the positive control, kojic acid, in the tyrosinase inhibition assay. American Chemical Society 2010 Article PeerReviewed Mohd. Sirat, Hasnah and Rezali, Mohamad Fazlin and Ujang, Zanariah (2010) Isolation and identification of radical scavenging and tyrosinase inhibition of polyphenols from tibouchina semidecandra L. Journal Of Agricultural and Food Chemistry, 58 (19). 10404 - 10409. ISSN 0021-8561 http://dx.doi.org/10.1021/jf102231h DOI:10.1021/jf102231h |
| spellingShingle | Q Science Mohd. Sirat, Hasnah Rezali, Mohamad Fazlin Ujang, Zanariah Isolation and identification of radical scavenging and tyrosinase inhibition of polyphenols from tibouchina semidecandra L. |
| title | Isolation and identification of radical scavenging and tyrosinase inhibition of polyphenols from tibouchina semidecandra L. |
| title_full | Isolation and identification of radical scavenging and tyrosinase inhibition of polyphenols from tibouchina semidecandra L. |
| title_fullStr | Isolation and identification of radical scavenging and tyrosinase inhibition of polyphenols from tibouchina semidecandra L. |
| title_full_unstemmed | Isolation and identification of radical scavenging and tyrosinase inhibition of polyphenols from tibouchina semidecandra L. |
| title_short | Isolation and identification of radical scavenging and tyrosinase inhibition of polyphenols from tibouchina semidecandra L. |
| title_sort | isolation and identification of radical scavenging and tyrosinase inhibition of polyphenols from tibouchina semidecandra l |
| topic | Q Science |
| work_keys_str_mv | AT mohdsirathasnah isolationandidentificationofradicalscavengingandtyrosinaseinhibitionofpolyphenolsfromtibouchinasemidecandral AT rezalimohamadfazlin isolationandidentificationofradicalscavengingandtyrosinaseinhibitionofpolyphenolsfromtibouchinasemidecandral AT ujangzanariah isolationandidentificationofradicalscavengingandtyrosinaseinhibitionofpolyphenolsfromtibouchinasemidecandral |