Flavonoids identification, total flavonoids content and antioxidant activity of the extracts from the leaves as well as flowers of Cassia angustifolia were determined. Five different extraction techniques were used fo...Flavonoids identification, total flavonoids content and antioxidant activity of the extracts from the leaves as well as flowers of Cassia angustifolia were determined. Five different extraction techniques were used for the extraction of flavonoids from leaves and flowers. Total flavonoid contents (TFC) in the extracts were determined by UV-visible spectrophotometry. Individual flavonoids were identified and quantified by high-performance liquid chromatography coupled with photodiode array detection and electrospray ioniza- tion tandem mass spectrometry (HPLC-PDA-ESI-MS). It has been examined that aqueous ethanol (70%) fractions of C. angustifolia flowers and leaves are highly rich in flavonoids and microwave extraction is the best method for the extraction of individual flavanoid constituents (1 - 9) as well as total flavonoid contents. It was also found that compound 8 was absent in the leaves and compounds 2 and 5 could not be identified. The extracts of C. angustifolia flowers and leaves show strong antioxidant activity.展开更多
A new flavonoid glucoside with a known one was isolated from the leaves of Cassia angustifolia. Based on the spectral analysis, including MS, ^1H NMR, ^13C NMR, DEPT, ^1H-1HCOSY, HMQC, HMBC and NOSEY, their chemical s...A new flavonoid glucoside with a known one was isolated from the leaves of Cassia angustifolia. Based on the spectral analysis, including MS, ^1H NMR, ^13C NMR, DEPT, ^1H-1HCOSY, HMQC, HMBC and NOSEY, their chemical structures were determined as kaempferol-3-O-[（6＇＇＇-O-trans-sinnapoyt）-β-D-glucopyranosyl （1 → 6）]-β-D-glucopyranoside 1 and apigenin-6,8-di-C-glycoside 2.展开更多
Two new glycosides were isolated and characterized by spectral analysis from the seeds of Cassia obtusifolia and the leaves of Cassia angustifolia. The structure was elucidated as 1-hydroxyl-2-acetyl-3,8-dimethoxynaph...Two new glycosides were isolated and characterized by spectral analysis from the seeds of Cassia obtusifolia and the leaves of Cassia angustifolia. The structure was elucidated as 1-hydroxyl-2-acetyl-3,8-dimethoxynaphthalene-6-O-β-D-apiofuranosyl- （1→2）-β-D-glucopyranoside and 2-acetyl-3-methyl-8-methoxyl-1,4-naphthoquinone-6-O-β-D-glucopyranoside.展开更多
文摘Flavonoids identification, total flavonoids content and antioxidant activity of the extracts from the leaves as well as flowers of Cassia angustifolia were determined. Five different extraction techniques were used for the extraction of flavonoids from leaves and flowers. Total flavonoid contents (TFC) in the extracts were determined by UV-visible spectrophotometry. Individual flavonoids were identified and quantified by high-performance liquid chromatography coupled with photodiode array detection and electrospray ioniza- tion tandem mass spectrometry (HPLC-PDA-ESI-MS). It has been examined that aqueous ethanol (70%) fractions of C. angustifolia flowers and leaves are highly rich in flavonoids and microwave extraction is the best method for the extraction of individual flavanoid constituents (1 - 9) as well as total flavonoid contents. It was also found that compound 8 was absent in the leaves and compounds 2 and 5 could not be identified. The extracts of C. angustifolia flowers and leaves show strong antioxidant activity.
文摘A new flavonoid glucoside with a known one was isolated from the leaves of Cassia angustifolia. Based on the spectral analysis, including MS, ^1H NMR, ^13C NMR, DEPT, ^1H-1HCOSY, HMQC, HMBC and NOSEY, their chemical structures were determined as kaempferol-3-O-[（6＇＇＇-O-trans-sinnapoyt）-β-D-glucopyranosyl （1 → 6）]-β-D-glucopyranoside 1 and apigenin-6,8-di-C-glycoside 2.
文摘Two new glycosides were isolated and characterized by spectral analysis from the seeds of Cassia obtusifolia and the leaves of Cassia angustifolia. The structure was elucidated as 1-hydroxyl-2-acetyl-3,8-dimethoxynaphthalene-6-O-β-D-apiofuranosyl- （1→2）-β-D-glucopyranoside and 2-acetyl-3-methyl-8-methoxyl-1,4-naphthoquinone-6-O-β-D-glucopyranoside.
