From the known phytochemicals, the six C-glycosyl
flavones (shown in Figure 1), shaftoside (1), isomollupentin 7-O-[beta]-glucopyranoside, orientin (2), isoorientin (3), vitexin (4), and isovitexin (5) isolated from the methanolic extract of C.
Feeding response of corn earworm larvae (Lepidoptera: Noctuidae) on corn silks of varying
flavone content.
Concentrations of
flavone aglycones, DHPPG, and (+)-catechin were significantly lower in fertilized saplings (Table 1, [ILLUSTRATION FOR FIGURE 2 OMITTED]).
In contrast, the chromenone ring system of the
flavone molecule faces a larger, negatively charged, and hydrophilic cavity, which includes hydroxyl and carbonyl groups of Gly120, Ser125, Tyr133, and Glu202.
3.7- dihydroxy
flavone (2.5 mg/kg, 5 mg/kg, and 10 mg/kg), 3,3'-dihydroxy
flavone, 6,3'-dihydroxy
flavone, and 5,6-dihydroxy
flavone (5 mg/kg,10 mg/kg, and 20 mg/kg) were used.
The UV ([[lambda].sub.max]) spectrum and IR ([cm.sup.-1]) absorption bands were similar to
flavone. The MS gives M.F C21H21O10 showing peak at m/z 433.
These two profiles were among the most complex recorded here (Table 3 and Figure 1), and agreed with the
flavone diversity reported by Kawashty and El-Garf (2000) for other species of Verbena.
Chemically,
flavones are substances of phenolic nature and are characterized by having two benzene aromatic rings united by a bridge with three carbon atoms.
LT molecules have a hydroxyl group at the 3' position on the
flavone skeleton, and a crucial enzyme that introduces the 3'-hydroxyl group on the corresponding precursor has been identified as
flavone 3'-hydroxylase (F3'H) (Figure 3).
Kim, "Jaceosidin, a natural
flavone, promotes angiogenesis via activation of VEGFR2/FAK/PI3K/AKT/NF-[kappa]B signaling pathways in endothelial cells," Experimental Biology and Medicine, vol.
Among these organic compounds, it is possible to find phenolic compounds, esters and flavonoids (flavonols,
flavones, flavonones, dihydroflavonols and chalcones), terpenes, steroids, aromatic beta-aldehydes, alcohols, sesquiterpenes and stilbene (Aga et al., 1994; Russo et al., 2002).