myricetin-3-o-rhamnoside and quercitrin

The development of bioproducts able to accelerate wound healing is an important topic in biomedicine. In the current study, Pistacia lentiscus distilled leaves (PDL) extract and its two isolated glycosylated flavonoids, myricetin-3-O-rhamnoside (MM) and quercetin-3-O-rhamnoside (QM), were evaluated for their wound healing activity, including evaluation of wound closure, revascularization, wound re-epithelialization, fibroblast proliferation, and collagen deposition on rat skin samples. Moreover, hydroxyproline content, C-reactive protein (CRP) level, and immunohistochemistry study were evaluated on blood and tissues collected from rats on day 14 post-wounding. Results showed that the topical application of PDL (at a concentration of 20 mg/ml) (PDL 20), MM, and QM increased wound healing and decreased inflammatory cells infiltration compared to the negative control group. Moreover, the cutaneous wound tissues treated with PDL 20, MM, and QM exhibited significantly higher hydroxyproline content than the negative control group, which means a high collagen biosynthesis in wound tissues. Indeed, the level of the inflammatory protein CRP is significantly lower in groups treated with MM and QM than in the negative control group. Also, the expression of the pro-inflammatory factor TNF-α and the angiogenesis marker CD-31 in PDL 20, MM, and QM treated groups is lower than in the negative control group. Moreover, MM, and QM induced a good elastase inhibition at 100 µg/ml compared to the standard epigallocatechin gallate. Therefore, PDL 20, MM, and QM could be used as effective cutaneous wound healing agents.

Topics: Administration, Topical; Animals; Mannosides; Pistacia; Plant Extracts; Plant Leaves; Quercetin; Rats; Rats, Wistar; Tumor Necrosis Factor-alpha; Wound Healing

Rosebay willowherb (Epilobium angustifolium) contains large amounts of polyphenolic compounds, including tellimagrandin I-based oligomeric ellagitannins (ETs). The aim of this study was to assess the interpopulational and inter-organ variability of the polyphenol fingerprint of E. angustifolium. Seven ETs, 11 flavonol glycosides and neochlorogenic acid were quantified by UHPLC-DAD-ESI-QqQ-MS in the leaves, flowers and stem parts of plants from 10 populations. Total polyphenol content of leaves and flowers ranged from 150 to 200 mg/g dry wt, of which 90% was constituted by dimeric to heptameric ETs. Flowers contained, on average, 10% more oenothein B (dimeric ET) and 2 times less oenothein A (trimeric ET) than leaves. Tetrameric and pentameric ETs exhibited rather similar levels in leaves and flowers whereas hexameric and heptameric were 3-4 times more abundant in flowers than in leaves. Quercetin-3-O-rhamnoside, myricetin-3-O-rhamnoside and kaempferol-3-O-rhamnoside were specific to flower tissue and were absent from leaves. The inflorescence stem showed the highest content in total polyphenols with an average of 250 mg/g dry wt and contained remarkably large amounts of oenothein B and A. Polyphenol content steadily decreased along the inflorescence stem and reached its lowest level in the vegetative part of the stem. The interpopulational variability of most polyphenols was within a two- to threefold range across the 10 sampled populations. Myricetin-3-O-glucoside and myricetin-3-O-glucuronide, however, showed a more population-specific distribution with concentrations varying from 0 to 2.3 mg/g dry wt. Finally, this study showed that the levels of oenothein B and A in the plant are not interdependent but that their relative abundance is constant within a population.

Topics: Epilobium; Flavonoids; Flavonols; Gallic Acid; Glucosides; Glycosides; Hydrolyzable Tannins; Kaempferols; Mannosides; Onagraceae; Plant Leaves; Polyphenols; Quercetin

Corylus maxima Mill. (Betulaceae) leaves have been used in traditional medicine both internally and externally, nevertheless phytochemical exploration of the plant remains incomplete. In this study, the in vitro antioxidant activity and polyphenolic composition of the ethyl acetate and methanolic extracts of C. maxima leaves and bark are reported for the first time. The radical scavenging activities of the extracts were investigated by the ABTS and DPPH assays. All the extracts of C. maxima possessed notable antioxidant activity. By mean of a HPLC-DAD-ESI-TOF and a HPLC-DAD-ESI-MS/MS method, altogether twenty-two phenolics were tentatively characterised: one flavan derivative (1), seven flavonol derivatives (4, 6, 12, 13, 16, 20 and 21) and fourteen diarylheptanoids (2, 3, 5, 7-11, 14, 15, 17-19 and 22). The amount of the two main flavonoids - myricetin-3-O-rhamnoside (6) and quercetin-3-O-rhamnoside (13) - and two diarylheptanoids - oregonin (3) and hirsutenone (15) - in the extracts were determined by a validated HPLC-ESI-MS/MS method in multiple reaction monitoring (MRM) mode. Our results showed that C. maxima could be considered as a valuable source of pharmacologically important natural products that might contribute to the revaluation of the phytotherapeutical potential of the plant.

Topics: Antioxidants; Catechols; Chromatography, High Pressure Liquid; Corylus; Diarylheptanoids; Flavonoids; Mannosides; Phenols; Plant Extracts; Plant Leaves; Quercetin; Spectrometry, Mass, Electrospray Ionization; Tandem Mass Spectrometry