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The hydroethanolic extract obtained from the dry leaves of Fridericia chica (HEFc) underwent several fractionations by different chromatographic techniques. The ethyl acetate and dichloromethane fraction were subjected to phytochemical analysis, resulting in the identification and isolation of scutellarein (1) and in a fraction rich in carajurone (2). They were tested for cytotoxicity in CHO-K1 and the antibacterial activity and mode of action by in vitro assays. The HEFc and scutellarein (1) presented no cytotoxicity. The results showed good antibacterial effect of HEFc against Streptococcus pyogenes and Staphylococcus aureus and moderate activity for Staphylococcus epidermidis, Pseudomonas aeruginosa and Salmonella typhimurium. The fraction containing the compound carajurone (2) showed good activity against Staphylococcus aureus and Staphylococcus epidermidis and moderate activity against Streptococcus pyogenes. Scutellarein (1) showed no activity against the bacteria tested. HEFc antibacterial mode of action appeared to be associated with changes in the permeability of bacterial membranes and nucleotide leakage. [ABSTRACT FROM AUTHOR]

To search novel therapy for human colon cancer, scutellarein identified from Scutellaria barbata was investigated using HCT116 cells. As a result, scutellarein can induce apoptosis of HCT116 cells. Further investigation for the mechanism has revealed scutellarein can increase the production of intracellular ROS and lead to the collapse of mitochondrial membrane potential. Meanwhile, the activity of caspase-3 in HCT116 cells was elevated by scutellarein. Moreover, down-regulated Bcl-2 and up-regulated Bax were observed. Additionaly, scutellarein resulted in cytochrome c release from mitochondria. These results indicated the apoptosis induction of HCT116 cells by scutellarein was implemented through ROS-mediated mitochondria-dependent pathway. [ABSTRACT FROM AUTHOR]

Greenhouse experiments were conducted to determine the effects of nitrogen (N), phosphorus (P), and potassium (K) fertilizer on biomass yield and flavonoid content of American skullcap (Scutellaria lateriflora). Each experiment was carried out two times and consisted of six levels of each nutrient. The regressions gave maxima for dry matter, baicalein yield, and chrysin yield at 446, 412, and 351 kg N/ha for N fertilizer, respectively. Dry matter yield exhibited linear response to P application. The yield of scutellarein, baicalin, baicalein, and chrysin increased with addition of P. The regression gave maximum for dry matter at 208 kg K/ha for K fertilizer. A linear response to K fertilization was observed for scutellarein concentration. P application had the greatest effect on the flavonoids analyzed, whereas K had least, which may be attributed in part to the presence of K in the fritted clay medium. [ABSTRACT FROM AUTHOR]

The inclusion complexation behavior of scutellarein (SCUE) with 2-hydroxypropyl-β-cyclodextrin (HP-β-CD) has been investigated in both solution and in the solid state. SCUE/HP-β-CD solid system was prepared by suspension method. The formation of SCUE/HP-β-CD complex in aqueous solution was demonstrated by fluorescence spectroscopy, and the Job plot showed a maximum at a molar fraction of 0.5, indicating 1:1 inclusion complexation between SCUE and HP-β-CD. However, SCUE/HP-β-CD inclusion complex was characterized by means of XRD, DSC, 1H, and two-dimensional NMR. Through the complexation between HP-β-CD and SCUE, the water solubility and antitumor activity of SCUE were obviously increased. This satisfactory water solubility and high antitumor activity of the SCUE/HP-β-CD complex will be potentially useful for its application on human colon cancer chemotherapies. [ABSTRACT FROM AUTHOR]

A field experiment was conducted in Alabama to determine the effect of timing and frequency of harvest on shoot yield and flavonoid content of American skullcap. In the first year (2008), harvesting twice gave 36% higher yield than harvesting once. In the second year (2009), plant die-off late in the season prevented a comparison of two and three harvests, so only the effects of early and late harvest were compared. There was no difference in yield between early or late harvesting. Plant height and density, percent dry matter, and shoot yield were higher in the first harvest than the second harvest. In 2008, the yield and concentration of flavonoid baicalein was the highest. In 2009, the yield and concentration of baicalin was the highest, followed by baicalein and apigenin. There were no differences in flavonoid yield between early and late harvest. Flavonoid yield in 2009 was 58% higher in the first harvest than in the second. [ABSTRACT FROM PUBLISHER]

Scutellarein is a component of Scutellaria, recently known as a potent cytotoxic agent on human leukaemia cells. The aim of this study was the synthesis of scutellarein and its methylated derivative. The new features are the innovating method to afford flavones from flavanones and the A-ring regioselective bromination step that lead to the target molecule by a facile and high-yielding pathway. [ABSTRACT FROM PUBLISHER]

The potent antioxidant activity of flavonoids relevant to their ability to scavenge reactive oxygen species is the most important function of flavonoids. Density functional theory calculations were explored to investigate the antioxidant activity of flavonoid compounds such as apigenin and scutellarein. The biological characteristics are dependent on electronic parameters, describing the charge distribution on the rings of the flavonoid molecules. The computation of structural and various molecular descriptors such as polarizability, dipole moment, energy gap, homolytic O-H bond dissociation enthalpies (BDEs), ionization potential (IP), electron affinity, hardness, softness, electronegativity, electrophilic index and density plot of molecular orbital for neutral as well as radical species were carried out and studied. The B3LYP/6-311G(d,p) basis set was adopted for all the computations. This computation reveals that scutellarein exhibits higher degree of antioxidant activity than apigenin. Their dipole moment and polarizability analysis show that both the compounds are polar in nature and have the capacity to polarize other atoms. [ABSTRACT FROM AUTHOR]

A low-temperature, timesaving, lower solvent consumption, and energy cost and multi-stage countercurrent extraction (MCCE) technique was developed for pilot-scale production of scutellarein from Erigeron breviscapus (Vant.) Hand-Mazz. The optimum conditions of MCCE process were obtained using the orthogonal array design method, i.e., 70% (v/v) of ethanol water solution, 16 L/kg of solvent to herbal sample ratio, 45°C of extraction temperature and 30 min of extraction time. A comparison between the MCCE technique and single pot extraction (SPE) under respective optimized operation conditions was made and time courses of scutellarein of MCCE and SPE processes were plotted, indicating that the MCCE technique can lower the extraction temperature and decrease five-sixth of the extraction time and two-thirds of the solvent consumption at the equivalent extraction yield of scutellarein. [ABSTRACT FROM AUTHOR]

The metabolism of scutellarein was investigated in rats. Four metabolites (M1-M4) together with scutellarein were detected and identified as scutellarein-glucuronides in rat plasma by HPLC-DAD, HPLC-MS, and HPLC-MS/MS. [ABSTRACT FROM AUTHOR]

An HPLC method was established for preparation of scutellarein from scutellarin using an enzymolysis reaction. The aglycone was identified as scutellarein with its chromatogram, UV, LC-MS, and 1 H-NMR spectra. Acid hydrolysis was tried in preliminary experiments, but enzymolysis was adopted after optimization of reaction conditions. High purity scutellarein (content 98.04%~98.36%) was prepared in this way for the first time, which could be used as a working reference substance. [ABSTRACT FROM AUTHOR]