hibifolin and hyperoside

To explore the mechanism of the absorption of flavonoids from Abelmoschus manihot flowers, in situ intestinal recirculation was performed to study the effect of the absorption at different concentrations and different intestinal regions. To evaluate the conditions of the absorption of six flavonoids from Abelmoschus manihot flowers, the concentrations of Abelmoschus manihot in the perfusion solution were determined by HPLC at predesigned time. And we have investigated the inhibitory effect of six flavonoids from Abelmoschus manihot flowers on P-glycoprotein (P-gp) drug efflux pump. The results demonstrated that the absorption rates of flavonoids from Abelmoschus manihot flowers are not significantly different (P > 0.05) at various drug concentrations, the absorption of flavonoids from Abelmoschus manihot flowers is a first-order process with the passive diffusion mechanism. The absorption rates of each of flavonoids are significantly different. The absorption rate of flavonoid glycoside was lower than that of aglycone; the flavonoids from Abelmoschus manihot flowers could be absorbed in all of the intestinal segments. The best parts of intestine to absorb hyperoside and myricetin are jejunum and duodenum, separately. Verapamil could enhance the absorption of isoquercitrin, hyperoside, myricetin and quercetin-3'-O-glucoside by inhibiting P-glycoprotein (P-gp) drug efflux pump.

Topics: Abelmoschus; Animals; ATP Binding Cassette Transporter, Subfamily B; Flavonoids; Flowers; Glucosides; Intestinal Absorption; Male; Perfusion; Plant Extracts; Plants, Medicinal; Quercetin; Rats; Rats, Sprague-Dawley; Verapamil

Depression is the most common psychiatric comorbidity in patients with epilepsy. Searching for antiepileptic (anticonvulsant) and antidepressant-like medicines from natural products is very important for the treatment of this disease. The flower of Abelmoschus manihot (Linn.) Medicus has been reported to have neuroprotective effect against cerebral ischemia injury. In order to further explore the activity of Abelmoschus manihot on the central nervous system, the anticonvulsant and antidepressant-like effects of Abelmoschus manihot ethanol extract (AMEE) as well as its potential active components in vivo was investigated in the present study. It was found that AMEE could protect mice against PTZ-induced clonic convulsions and mortality. AMEE could also decrease immobility time in the FST in mice. Furthermore, the potential active components of AMEE in rat brain were identified by ultra performance liquid chromatography-mass spectrometer (UPLC-MS). Five parent components including isoquercitrin, hyperoside, hibifolin, quercetin-3'-O-glucoside, quercetin and three metabolites were detected in rat brain after administration of AMEE. In conclusion, eight flavonoids were identified in rat brain after administration of AMEE; meanwhile, these flavonoids might represent the potential bioactive components of AMEE and contribute to its anticonvulsant and antidepressant-like activity in vivo.

Topics: Abelmoschus; Animals; Anticonvulsants; Antidepressive Agents; Brain; Chromatography, Liquid; Drug Evaluation; Ethanol; Exercise Test; Flavonoids; Flowers; Male; Mice; Mice, Inbred ICR; Pentylenetetrazole; Plant Extracts; Quercetin; Rats; Rats, Sprague-Dawley; Seizures; Time Factors

A high-performance liquid chromatography method is developed for the simultaneous quantification of seven flavonols, namely quercetin-3-O-robinobioside, hyperin, isoquercetin, hibifolin, myricetin, quercetin-3'-O-glucoside, and quercetin, in the flower of Abelmoschus manihot. These seven flavonols are selected as chemical markers because they are the major pharmacologically active constituents in the flower. The method involves the use of a Thermo ODS-2HYEPRSIL reversed-phase column (5 microm, 250 x 4.6 mm) at 25 degrees C with a mixture of acetonitrile and aqueous H(3)PO(4) as the mobile phase and detection at 370 nm. The recovery of the method is 94.31-107.08% with an RSD < or = 3.14% and the linearity (r(2) > 0.9996) is obtained for all the flavonoids. The current assay method can be readily utilized for the determination of the flavonols present in the flower and is considered to be suitable for the quality control of A. manihot samples. The comparison of flowers collected from nine locations shows that flavonoid glucoside is more stable than aglycon in the flower. This is the first study that analyzes the stability of flavonoids in the flower of A. manihot. This research also provides important evidence that the flower is a potentially abundant resource for obtaining hibifolin.

Topics: Abelmoschus; Chromatography, High Pressure Liquid; Drug Stability; Flavonoids; Flavonols; Flowers; Indicators and Reagents; Quercetin; Reproducibility of Results