Phytochemicals with Antioxidant from Melastomataceae

Author

PROF DR HASNAH M SIRAT  
Hasnah M. Sirat*, Deny Susanti, M. Fazlin Rezali and Farediah Ahmad
Department of Chemistry, Faculty of Science,
Universiti Teknologi Malaysia
81310 Skudai, Johor
e-mail: This email address is being protected from spambots. You need JavaScript enabled to view it.

Language

English

Title

Phytochemicals with Antioxidant from Melastomataceae

Proceeding

7th INTRACOM – 2nd ICBWI 2009

Date

24th July 2009

Place Held

PWTC, Kuala Lumpur

Abstract

Phytochemical and bioactivity studies of Melastomataceae have yielded several interesting compounds, mainly flavonoids and flavonoid glycosides as well as terpenoids. The leaves of Melastoma decemfidum yielded kaempferol, naringenin, quercetin, quercitrin, kaempferol-3-O-(2”,6”-di-O-p-trans-coumaroyl)-glucoside, kaempferol-3-O--D-glucoside, and hyperin, while the flowers gave terpenoids, betulinic acid and -amyrin. The leaves of Tibouchina semidecandra yielded four compounds, identified as quercetin 3-O-α-L-(2′′-O-acetyl)arabinofuranoside, avicularin, together with quercetin, and quercitrin, while the stem barks gave one ellagitannin, identified as 3,3′-O-dimethyl ellagic acid 4-O-α-L-rhamnopyranoside. The antioxidant assay showed the ethyl acetate extract, the methanol extract and the pure isolated phytochemicals, kaempferol, kaempferol-3-O-(2”,6”-di-O-p-trans-coumaroyl)glucoside, kaempferol-3-O--D-glucose, hyperin, quercetin and quercitrin showed strong activities with inhibition more than 90% in the FTC method. Quercetin was found to be the most active as radical scavenger in DPPH-UV and ESR method with IC50 of 0.69 and 0.65 M, respectively.

Keywords

Antioxidant, Melastomataceae

Session

Symposium 4B (ICBWI)

Topic

Biomolecule Discovery