acacetin and tricin

The mechanism of interactions between a flavonoid glycoside (linarin) and 6 flavonoids with various hydroxyl and methoxyl substituents (luteolin, apigenin, acacetin, tricin, 5,3',4'-trihydroxy-6,7-dimethoxyflavone, and 5,7,4'-trihydroxy-6,3',5'-trimethoxyflavone) and bovine serum albumin (BSA) were investigated by multi-spectroscopy, molecular docking, and quadrupole (Q)-time of flight (TOF) high resolution (HR) mass spectrometry (MS). Fluorescence spectra and molecular docking predicted that each of the flavonoids had only one probable binding site inside the hydrophobic cleft of BSA. The binding constants appeared to correlate positively with the number of hydroxyl groups, and negatively with the number of methoxyl groups. In addition, hydroxyls on ring B bound more easily with BSA than those on ring A. The change in conformation of BSA after binding suggested that the quenching mechanism was static quenching combined with nonradiative energy transfer. The results of Q-TOF HR-MS were consistent with fluorescence quenching and molecular docking.

Topics: Apigenin; Binding Sites; Energy Transfer; Flavones; Flavonoids; Hydroxylation; Luteolin; Mass Spectrometry; Molecular Docking Simulation; Protein Binding; Serum Albumin, Bovine; Spectrometry, Fluorescence

To study the flavonoids in the fruits of Buddleja lindleyana.. The compounds were separated by repeated silica gel, RP-18 and Sephadex LH-20. Their structures were elucidated on the basis of chemical evidence and spectral data.. Five flavonoids were isolated and identified as luteolin (1), tricin (2), acacetin (3), acacetin-7-O-β-D-glucopyranoside (4) and linarin(5).. Compounds 3,4 and 5 are isolated from fruits of Buddleja lindleyana for the first time. Compound 2 is isolated from fruits of Buddleja lindleyana for the first time.

Topics: Buddleja; Flavones; Flavonoids; Fruit; Glycosides; Luteolin; Phytochemicals

To investigate the chemical constituents of the flowers of Chrysanthemum indicum.. The chemical constituents were isolated by various column chromatographic methods. The structures were identified by spectral data.. Twelve compounds were isolated and identified as acacetin (1), tricin (2), 2',4'-dihydroxychalcone(3), 5-hydroxy-4',7-dimethoxyflavon(4),7hydroxyflavonone (5), isorhamnetin (6),5,6,7-trihydroxy- 3',4', 5'-trimethoxyflanon (7 ), quercetin (8) , (3 beta, 5 alpha, 6 beta, 7 beta, 14 beta)-eudesmen-3,5,6,11-tetrol (9), syringaresinol (10), liriodendrin (11), and genkwanin (12).. Compounds 3-7, 10-12 were isolated from this species for the first time, and compounds 3, 5, 7, 10, 11 were obtained from genus Chrysanthemum for the first time.

Topics: Chalcones; Chrysanthemum; Flavones; Flavonoids; Flavonols; Flowers; Furans; Glucosides; Lignans; Quercetin