Isovitexin

About: Isovitexin is a research topic. Over the lifetime, 526 publications have been published within this topic receiving 11525 citations. The topic is also known as: 6-Glucosylapigenin & Isovitexin.

[Chemical Constituents from Leaves of Hibiscus syriacus and Their α-Glucosidase Inhibitory Activities].

Abstract: Objective To study the chemical constituents from Hibiscus syriacus leaves and their α-glucosidase inhibitory activities. Methods Column chromatography including macroporous resins, silica gel and Sephadex LH-20 were used for the isolation and purification of all compounds. Spectroscopic methods including physical and chemical properties, 1H-NMR and 13C-NMR were used for the identification of structures. Their α-glucosidase inhibitory activities were detected by a 96-well microplate. Results 15 compounds were isolated and identified as β-sitosterol(1), β-daucostero (2), β-amyrin (3), oleanolic acid (4), stigmast-4-en-3-one (5), friedelin (6), syriacusin A (7), kaempferol (8), isovitexin (9), vitexin (10), apigenin (11), apigenin-7-O-β-D-glucopyranoside (12), luteolin-7-O-β-D-glucopyranoside (13), vitexin-7-O-β-D-glucopyranoside (14) and rutin (15). Conclusion All the compounds are isolated from the leaves of Hibiscus syriacus for the first time. Taking acarbose as positive control, the α-glucosidase inhibitory activities of 15 compounds were evaluated. Compounds 7 and 9 have shown strong α-glucosidase inhibitory activities with IC50 of 39.03 ± 0.38 and 32.12 ± 0.62 mg/L, inhibition ratio of 94.95% and 97.15%, respectively.

Investigation on the Phytochemical Composition, Antioxidant and Enzyme Inhibition Potential of Polygonum Plebeium R.Br: A Comprehensive Approach to Disclose New Nutraceutical and Functional Food Ingredients.

Abstract: The present work describes medicinal potential and secondary metabolic picture of the methanol extract (PP-M) of Polygonum plebeium R.Br. and its fractions; hexane (PP-H), ethyl acetate (PP-E) and water (PP-W). In total bioactive component estimation, highest contents of phenolic (89.38±0.27 mgGAE/g extract) and flavonoid (51.21±0.43 mgQE/g extract) were observed in PP-E, and the same fraction exhibited the highest antioxidant potential in DPPH (324.80±4.09 mgTE/g extract), ABTS (563.18±11.39 mgTE/g extract), CUPRAC (411.33±15.49 mgTE/g extract) and FRAC (369.54±1.70 mgTE/g extract) assays. In Phosphomolybdenum activity assay, PP-H and PP-E showed nearly similar potential, however, PP-H was the most active (13.54±0.24 mgEDTAE/g extract) in metal chelating activity assay. PP-W was the stronger inhibitor (4.03±0.05 mgGALAE/g extract) of the enzyme AChE, while PP-H was potent inhibitor of BChE (5.62±0.27 mg GALAE/g extract). Interestingly, PP-E was inactive against BChE. Against tyrosinase activity, PP-E was again the most active fraction with inhibitory value of 71.89±1.44 mg KAE/g extract, followed by the activity of PP-M and PP-W. Antidiabetic potential was almost equally distributed among PP-M, PP-H and PP-E. For mapping the chemodiversity of P. plebeium, PP-M was analyzed through UHPLC/MS, which led to the identification of more than 50 compounds. Flavonoids were the main components derived from isovitexin, kaempferol and luteolin however, gallic acid, protocatechuic acid, gingerols and lyoniresinol 9'-sulfate were among important bioactive phenols. These findings prompted to conclude that Polygonum plebeium can be a significant source to offer new ingredient for nutraceuticals and functional foods.

In situ identification, localization and quantification of flavones in petals and green leaves of Silene pratensis grown under different light regimes

Abstract: Quartz optic microscopy with variable wavelength illumination was used to locate and quantify the ultraviolet absorbing flavone isovitexin 7-0-qlucoside in leaf and petal epidermis in Silene pratensis. Mean vacuolar absorption spectra and mean cell wall thickness were used to estimate flavone contents in different organs. The flavone spectrum in vivo coincides with that found in vitro (absorption peaks at 273 and 335 nm). Flavone concentration in the green leaves is determined by the light levels under which individual plants were raised; with low levels (8,000 lux) a few upper epidermal cells show faint absorption at 335 nm. In plants raised at 18,000 lux, 60–70 % of the upper epidermal cells absorbed at 334 nm and flavone concentration in the absorbing cells was 1–3 mM. In plants raised under high light intensity (36,000 lux), most of the upper epidermal cells absorbed at 335 nm and the flavone concentration in the cells ranged from 8.5 to 15 mM. In the high light intensity plants some lower epidermal cells also absorb at 335 nm (flavone concentrations 2–5 mM). In all plants investigated, nearly all the cells of the upper epidermis of the netals absorb strongly at 335 nm (concentrations exceeding 19 mM).

Inhibition of mitochondrial respiration by the flavone aglycone isovitexin causes aberrant petal and leaf morphology in Silene latifolia

Abstract: The morphological mutant “isovitexin” in Silene latifolia (the white campion) has small and up-curled petals and leaves. In this mutant the aglycone isovitexin is the only flavone present in the vacuole. In the present study it is shown that isovitexin has a strong toxic effect on mitochondria that is to a large extent abolished by glycosylation. This effect can be used to explain the aberrant morphology. Isovitexin acts at the level of the ubiquinone pool; cytochrome c — cytochrome aa3 oxidase activity was unaffected, and with either reduced nicotinamide adenine dinucleotide or succinate as a respiratory substrate, effects on respiration were found in Silene leaves-, potato (Solanum tuberosum) tuber- and sweet potato (Ipomoea batata L.) tuber mitochondria. Since in sweet potato electron transport via the cyanide insensitive pathway was also inhibited, with the ubiquinone pool as the only component (besides the dehydrogenases) shared by these two pathways, the site of inhibition must be at this level.