Anti-inflammatory, antiviral and quantitative study of quercetin-3-O-β-D-glucuronide in Polygonum perfoliatum L

Beneficial Effects of Hydroalcoholic Extract from Rosa Roxburghii Tratt Fruit on Hyperlipidemia in High-Fat-Fed Rats

Background

Rosa roxburghii Tratt fruit is extensively used as a medicinal and edible resource in China due to its unique bioactivities. In this research, we aimed to characterize its phenolic acid composition and investigate the potential hypolipidemic effect of this plant in a rat model of hyperlipidemia.

Methods

We evaluated the effects of hydroalcoholic extract of Rosa roxburghii Tratt fruit (HRT) on serum lipids, body weight, activities of lipoprotein metabolism and antioxidant enzymes, and gene expression of lipid metabolism in hyperlipidemic rats.

Results

HRT significantly reduced body weight gain and decreased serum and liver lipid levels in the hyperlipidemic rats. In addition, HRT treatment improved the activities of antioxidant enzymes, lipoprotein lipase, and hepatic lipase, downregulated the mRNA and protein expressions of sterol regulatory element-binding protein 1c and acetyl CoA carboxylase, and upregulated the mRNA and protein expressions of peroxisome proliferator-activated receptor α and low-density lipoprotein receptor in hepatic tissue.

Conclusions

The results showed that Rosa roxburghii Tratt fruit is rich in phenolic acids, and that it exerted lipid lowering effects in the hyperlipidemic rats.

The Pharmacological Activity, Biochemical Properties, and Pharmacokinetics of the Major Natural Polyphenolic Flavonoid: Quercetin

Flavonoids are a class of natural substances present in plants, fruits, vegetables, wine, bulbs, bark, stems, roots, and tea. Several attempts are being made to isolate such natural products, which are popular for their health benefits. Flavonoids are now seen as an essential component in a number of cosmetic, pharmaceutical, and medicinal formulations. Quercetin is the major polyphenolic flavonoid found in food products, including berries, apples, cauliflower, tea, cabbage, nuts, and onions that have traditionally been treated as anticancer and antiviral, and used for the treatment of allergic, metabolic, and inflammatory disorders, eye and cardiovascular diseases, and arthritis. Pharmacologically, quercetin has been examined against various microorganisms and parasites, including pathogenic bacteria, viruses, and Plasmodium, Babesia, and Theileria parasites. Additionally, it has shown beneficial effects against Alzheimer’s disease (AD), and this activity is due to its inhibitory effect against acetylcholinesterase. It has also been documented to possess antioxidant, antifungal, anti-carcinogenic, hepatoprotective, and cytotoxic activity. Quercetin has been documented to accumulate in the lungs, liver, kidneys, and small intestines, with lower levels seen in the brain, heart, and spleen, and it is extracted through the renal, fecal, and respiratory systems. The current review examines the pharmacokinetics, as well as the toxic and biological activities of quercetin.

Quality Evaluation of Corydalis yanhusuo by High-Performance Liquid Chromatography Fingerprinting Coupled with Multicomponent Quantitative Analysis

Corydalis Rhizoma is the tuber of Corydalis yanhusuo W. T. Wang, which has been long used in traditional Chinese medicine. Herein, the quality of C. yanhusuo samples collected from 23 regions of three provinces in China is evaluated through high-performance liquid chromatography fingerprinting coupled with similarity, hierarchical clustering, and principal component analyses. Sample similarities are evaluated according to the State Food and Drug Administration requirements by selection of 18 characteristic chromatographic fingerprint peaks and are found to vary between 0.455 and 0.999. Moreover, common patterns of a typical local variety of C. yanhusuo sourced in the Panan County are established. The obtained results show that the combination of quantitative analysis and chromatographic fingerprint analysis can be readily utilized for quality control purposes, offering a comprehensive strategy for quality evaluation of C. yanhusuo and related products.

Identifying Synergistic Mechanisms of Multiple Ingredients in Shuangbai Tablets against Proteinuria by Virtual Screening and a Network Pharmacology Approach

Shuangbai Tablets (SBT), a traditional herbal mixture, has shown substantial clinical efficacy. However, a systematic mechanism of its active ingredients and pharmacological mechanisms of action against proteinuria continues being lacking. A network pharmacology approach was effectual in discovering the relationship of multiple ingredients and targets of the herbal mixture. This study aimed to identify key targets, major active ingredients, and pathways of SBT against proteinuria by network pharmacology approach combined with thin layer chromatography (TLC). Human phenotype (HP) disease analysis, gene ontology (GO) analysis, Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway enrichment analysis, and molecular docking were used in this study. To this end, a total of 48 candidate targets of 118 active ingredients of SBT were identified. Network analysis showed PTGS2, ESR1, and NOS2 to be the three key targets, and beta-sitosterol, quercetin, and berberine were the three major active ingredients; among them one of the major active ingredients, quercetin, was discriminated by TLC. These results of the functional enrichment analysis indicated that the most relevant disease including these 48 candidate proteins is proteinuria, SBT treated proteinuria by sympathetically regulating multiple biological pathways, such as the HIF-1, RAS, AGE-RAGE, and VEGF signaling pathways. Additionally, molecular docking validation suggested that major active ingredients of SBT were capable of binding to HIF-1A and VEGFA of the main pathways. Consequently, key targets, major active ingredients, and pathways based on data analysis of SBT against proteinuria were systematically identified confirming its utility and providing a new drug against proteinuria.

Total flavonoids, extracted from Polygonum knotweed L, exert beneficial hepatoprotection against liver injury

Hepatic function is of great concern in metabolic and immunological homeostasis. Traditionally, medical management to liver damage may benefit from phytomedicine, such as Chinese herbs. In southern China, Polygonum perfoliatum L can contribute to alleviating pathological symptoms of liver disease, such as hepatitis. However, bioactive compounds of hepatoprotection in this herb are still less to be investigated. In this study, clinical data of patients with drug-induced liver injury were collected on the basis of serological analyses. In addition, we extracted and identified total flavonoids from Polygonum perfoliatum L (TFPPL) before implementing biochemical experiments in vivo. In human data, the blood contents of liver function enzymes were visibly elevated, and the percentage of immune cells were abnormally changed. The data from the animal study showed that TFPPL-treated carbon tetrachloride-exposed mice resulted in reduced absolute liver mass and lowered blood levels of liver functional enzymes (alanine transaminase and aspartate transaminase). In enzyme-linked immunosorbent assay, the comparable data indicated that serological tumor necrosis factor α (TNF-α), interleukin 6, and heat shock protein 90 (Hsp90) contents were reduced in TFPPL-treated mice. In histopathological observations, TFPPL-treated mice exhibited reduced hepatocellular Hsp90, TNF-α, nuclear factor κ-light-chain-enhancer of activated B cells-p65 positive cells, and lowered Bax and caspase-3-labeled cells in the livers. Further, intrasplenic integrin β1, 5'-nucleotidase, and antigen KI-67 positive cells were increased after TFPPL treatments. Taken together, our present findings demonstrate that herb-extracted TFPPL exert potential hepatoprotective activities against chemical-induced liver damage in mice, possibly through the pharmacological mechanisms of inhibiting inflammatory stress and apoptosis, inactivating Hsp90 bioactivity in the liver, and improving splenic immunocompetence.

Dual Effect of Glucuronidation of a Pyrogallol-Type Phytophenol Antioxidant: A Comparison between Scutellarein and Scutellarin

To explore whether and how glucuronidation affects pyrogallol-type phytophenols, scutellarein and scutellarin (scutellarein-7-O-glucuronide) were comparatively investigated using a set of antioxidant analyses, including spectrophotometric analysis, UV-vis spectra analysis, and ultra-performance liquid chromatography coupled with electrospray ionization-quadrupole time-of-flight tandem mass spectrometry (UPLC-ESI-Q-TOF-MS/MS) analysis. In spectrophotometric analyses of the scavenging of 1,1-diphenyl-2-picrylhydrazyl (DPPH^•), 2,2'-azino-bis (3-ethylbenzothiazoline-6-sulfonic acid) (ABTS^+•), and 2-phenyl-4,4,5,5-tetramethylimidazoline-1-oxyl 3-oxide radicals (PTIO^•) and the reduction of Cu²⁺ ions, scutellarein showed lower IC₅₀ values than scutellarin. However, in ^•O₂^--scavenging spectrophotometric analysis, scutellarein showed higher IC₅₀ value than scutellarin. The analysis of UV-Vis spectra obtained after the Fe²⁺-chelating reaction of scutellarin showed a typical UV-Vis peak (λ_max = 611 nm), while scutellarein showed no typical peak. In UPLC-ESI-Q-TOF-MS/MS analysis, mixing of scutellarein with DPPH^• yielded MS peaks (m/z 678, 632, 615, 450, 420, 381, 329, 300, 288, 227, 196, 182, 161, and 117) corresponding to the scutellarein-DPPH adduct and an MS peak (m/z 570) corresponding to the scutellarein-scutellarein dimer. Scutellarin, however, generated no MS peak. On the basis of these findings, it can be concluded that glucuronidation of pyrogallol-type phytophenol antioxidants has a dual effect. On the one hand, glucuronidation can decrease the antioxidant potentials (except for ^•O₂^- scavenging) and further lower the possibility of radical adduct formation (RAF), while on the other hand, it can enhance the ^•O₂^--scavenging and Fe²⁺-chelating potentials.

Quercetin‑3‑O‑β‑D‑glucoside decreases the bioavailability of cyclosporin A through regulation of drug metabolizing enzymes, transporters and nuclear receptors in rats

Quercetin is a flavonoid compound that is widely present in food and drink. Quercetin-3-O-β-D-glucoside (Q3GA) is a major metabolite of quercetin. The aim of the present study was to investigate the effect of Q3GA on the pharmacokinetics of orally and intravenously administered cyclosporin A (CsA) in rats, and to assess the effect of Q3GA on drug-metabolizing enzymes (DMEs), drug transporters (DTs) and nuclear receptors (NRs). The pharmacokinetic parameters of CsA were measured following oral (10 mg/kg) and intravenous (2.5 mg/kg) administration of CsA in the presence or absence of Q3GA. The mRNA and protein expression levels of DMEs, DTs and NRs in the liver and small intestine were detected by quantitative polymerase chain reaction and western blot analysis. The results indicated that the intravenous administration of Q3GA (2.5, 5 or 10 mg/kg) for 7 consecutive days reduced the bioavailability of oral CsA. By contrast, the pharmacokinetics of the intravenous administration of CsA were not affected by Q3GA. However, the mRNA and protein expression levels of DMEs and DTs were inhibited by Q3GA. The activation of DMEs and DTs by NRs, and the interplay between DMEs and DTs, may explain these results. The present study identified a novel flavonoid-drug interaction, which may have implications for patients taking CsA and quercetin supplements or on a quercetin-containing diet.

Unlocking the in vitro anti-inflammatory and antidiabetic potential of Polygonum maritimum

CONTEXT

Several Polygonum species (Polygonaceae) are used in traditional medicine in Asia, Europe and Africa to treat inflammation and diabetes.

OBJECTIVE

Evaluate the in vitro antioxidant, anti-inflammatory and antidiabetic potential of methanol and dichloromethane extracts of leaves and roots of the halophyte Polygonum maritimum L.

MATERIAL AND METHODS

Antioxidant activity was determined (up to 1 mg/mL) as radical-scavenging activity (RSA) of 2,2-diphenyl-1-picrylhydrazyl (DPPH), 2,2'-azino-bis(3-ethylbenzothiazoline-6-sulphonic acid) (ABTS), copper (CCA) and iron (ICA) chelating activities and iron reducing power (FRAP). NO production was measured in lipopolysaccharide (LPS)-stimulated macrophages for 24 h at concentrations up to 100 μg/mL and antidiabetic potential was assessed by α-amylase and α-glucosidase inhibition (up to 10 mg/mL) assays. The phytochemical composition of the extracts was determined by gas chromatography-mass spectrometry (GC-MS).

RESULTS

The methanol leaf extract had the highest activity against DPPH• (IC₅₀ = 26 μg/mL) and ABTS⁺• (IC₅₀ = 140 μg/mL), FRAP (IC₅₀ = 48 μg/mL) and CCA (IC₅₀ = 770 μg/mL). Only the dichloromethane leaf extract (LDCM) showed anti-inflammatory activity (IC₅₀ = 48 μg/mL). The methanol root (IC₅₀ = 19 μg/mL) and leaf (IC₅₀ = 29 μg/mL) extracts strongly inhibited baker's yeast α-glucosidase, but LDCM had higher rat's α-glucosidase inhibition (IC₅₀ = 2527 μg/mL) than acarbose (IC₅₀ = 4638 μg/mL). GC-MS analysis identified β-sitosterol, stigmasterol, 1-octacosanol and linolenic acid as possible molecules responsible for the observed bioactivities.

CONCLUSIONS

Our findings suggest P. maritimum as a source of high-value health promoting commodities for alleviating symptoms associated with oxidative and inflammatory diseases, including diabetes.

Bioactive effects of quercetin in the central nervous system: Focusing on the mechanisms of actions

Quercetin, a ubiquitous flavonoid that is widely distributed in plants is classified as a cognitive enhancer in traditional and oriental medicine. The protective effects of quercetin for the treatment of neurodegenerative disorders and cerebrovascular diseases have been demonstrated in both in vitro and in vivo studies. The free radical scavenging activity of quercetin has been well-documented, wherein quercetin has been observed to exhibit protective effects against oxidative stress mediated neuronal damage by modulating the expression of NRF-2 dependent antioxidant responsive elements, and attenuation of neuroinflammation by suppressing NF-κB signal transducer and activator of transcription-1 (STAT-1). Several in vitro and in vivo studies have also shown that quercetin destabilizes and enhances the clearance of abnormal protein such as beta- amyloid peptide and hyperphosphorlyated tau, the key pathological hallmarks of Alzheimer's disease. Quercetin enhances neurogenesis and neuronal longevity by modulating a broad number of kinase signaling cascades such as phophoinositide 3- kinase (P13-kinase), AKT/PKB tyrosine kinase and Protein kinase C (PKC). Quercetin has also been well reported for its ability to reverse cognitive impairment and memory enhancement during aging. The current review focuses on summarizing the recent findings on the neuroprotective effect of quercetin, its mechanism of action and its possible roles in the prevention of neurological disorders.

Systematic Analysis of Absorbed Anti-Inflammatory Constituents and Metabolites of Sarcandra glabra in Rat Plasma Using Ultra-High-Pressure Liquid Chromatography Coupled with Linear Trap Quadrupole Orbitrap Mass Spectrometry

Ultra-high-pressure liquid chromatography (UHPLC) was coupled with linear ion trap quadrupole Orbitrap mass spectrometry (LTQ-Orbitrap) and was used for the first time to systematically analyze the absorbed components and metabolites in rat plasma after oral administration of the water extract of Sarcandra glabra. This extract is a well-known Chinese herbal medicine for the treatment of inflammation and immunity related diseases. The anti-inflammatory activities of the absorbed components were evaluated by measuring nitric oxide (NO) production and proinflammatory genes expression in lipopolysaccharide (LPS)-stimulated murine RAW 264.7 macrophages. As a result, 54 components in Sarcandra glabra were detected in dosed rat plasma, and 36 of them were positively identified. Moreover, 23 metabolites were characterized and their originations were traced. Furthermore, 20 of the 24 studied components showed anti-inflammatory activities. These results provide evidence that this method efficiency detected constituents in plasma based on the anti-inflammatory mechanism of multiple components and would be a useful technique for screening multiple targets for natural medicine research.

Amelioration of free fatty acid-induced fatty liver by quercetin-3-O-β-D-glucuronide through modulation of peroxisome proliferator-activated receptor-alpha/sterol regulatory element-binding protein-1c signaling

AIM

To investigate the therapeutic effect and potential mechanisms of the natural flavonoid quercetin-3-O-β-D-glucuronide (Q3GA) against lipid metabolism disorder in free fatty acid (FFA)-induced fatty liver in vivo and in vitro.

METHODS

Fat accumulation was documented by oil red O staining, and intracellular triglyceride levels were detected by triglyceride(TG) enzymatic assay. Flow cytometry and enzyme-linked immunoassay assay were performed to observe the effect of Q3GA on lipotoxicity and inflammation response of primary rat hepatocytes with FFA treatment. Administration with Q3GA at doses of 25 and 50 mg/kg from the fifth week during high fat diet (HFD) induced non-alcoholic fatty liver disease (NAFLD) model for 8 weeks. Expression of the genes involved in the lipogenesis and fatty acid β-oxidation were assayed by reverse transcription polymerase chain reaction.

RESULTS

Q3GA reduced bodyweight gain, liver weight, liver index, dyslipidemia and hepatic TG level in a dose-dependant manner. In the FFA-overloaded primary rat hepatocytes, Q3GA decreased the fat overload and TG content, inhibited hepatocyte apoptosis and reduced inflammation cytokine expression. Importantly, the histopathological examination of liver showed that Q3GA could decrease hepatic lipid accumulation and liver injury. Besides, Q3GA decreased the expression of sterol regulatory element-binding protein-1c (SREBP-1c), fatty acid synthase and increased the expression of peroxisome proliferator-activated receptor-α (PPAR-α), carnitine palmitoyl-transferase 1 and medium-chain acyl-coenzyme A dehydrogenase in vivo and in vitro.

CONCLUSION

The therapeutic effect of Q3GA on lipid metabolism disorder in FFA-induced fatty liver rats is partly due to downregulating SREBP-1c and upregulating PPAR-α-mediated metabolic pathways.

Simultaneous determination of esculetin, quercetin-3-O-β-D-glucuronide, quercetin-3-O-β -D-glucuronopyranside methyl ester and quercetin in effective part of Polygonum Perfoliatum L. using high performace liquid chromatography

Objective:

In the present study, a high performance liquid chromatography (HPLC) coupled with photodiode array detection was developed for simultaneous quantitation of esculetin, quercetin-3-O-β-D-glucuronide, quercetin-3-O-β-D- glucuronopyranoside methyl ester and quercetin in Polygonum perfoliatum L.

Materials and Methods:

The chromatographic separations were performed on a reversed-phase C₁₈ column using a mobile phase composed of acetonitrile -0.5% aqueous acetic acid with gradient elution. The calibration curves for the analytes demonstrated good linearities within the investigated ranges. The satisfactory intra- and inter-day precision, repeatability and stability of the developed analytical method were shown in the method validation procedure. The recoveries of the established method ranged from 95.76 to 102.10% for all the analytes.

Results:

This proposed method was successfully applied for simultaneous quantification of the four compounds in effective part of Polygonum perfoliatum L. from different regions. Hierarchical clustering analysis (HCA) and principal components analysis (PCA) were performed to characterize and classify the samples based on the contents of the four compounds in Polygonum perfoliatum L.

Conclusion:

The established HPLC method combined with chemometric approaches was proven to be useful and efficient for quality control of Polygonum perfoliatum L.

A water-soluble inclusion complex of pedunculoside with the polymer β-cyclodextrin: a novel anti-inflammation agent with low toxicity

More than 50% of new drug candidates in drug discovery are lipophilic and exhibit poor aqueous solubility, which results in poor bioavailability and a lack of dose proportionality. Here, we improved the solubility of pedunculoside (PE) by generating a water-soluble inclusion complex composed of PE and the polymer β-cyclodextrin (CDP). We characterized this novel complex by 1H NMR, FT-IR, UV-vis spectroscopy, powder X-ray diffractometry and thermogravimetric analysis. The ratio of β-cyclodextrin (β-CD) units in CDP to PE was determined to be 2∶1. The KD value of the inclusion complex was determined to be 4.29×10(-3) mol•L(-1). In contrast to the low solubility of PE, the water-solubility of the PE-CDP complex was greatly enhanced. A preclinical toxicological study indicated that PE-CDP was well tolerated for a single administration. Importantly, the anti-inflammation potency of the PE-CDP complex was higher than that of PE. As a result, the formation of inclusion complexes by water-soluble CDP opens up possible aqueous applications of insoluble drug candidates in drug delivery.

Biocatalytic polymer coatings: on-demand drug synthesis and localized therapeutic effect under dynamic cell culture conditions

Biocatalytic surface coatings are prepared herein for localized synthesis of drugs and their on-demand, site-specific delivery to adhering cells. This novel approach is based on the incorporation of an enzyme into multilayered polymer coatings to accomplish enzyme-prodrug therapy (EPT). The build-up of enzyme-containing multilayered coatings is characterized and correlations are drawn between the multilayer film assembly conditions and the enzymatic activity of the resulting coatings. Therapeutic effect elicited by the substrate mediated EPT (SMEPT) strategy is investigated using a prodrug for an anticancer agent, SN-38. The performance of biocatalytic coatings under flow conditions is investigated and it is demonstrated that EPT allows synthesizing the drugs on-demand, at the time desired and in a controllable amount to suit particular applications. Finally, using cells cultured in sequentially connected flow chambers, it is demonstrated that SMEPT affords a site-specific drug delivery, that is, exerts a higher therapeutic effect in cells adhering directly to the biocatalytic coatings than in the cells cultured "downstream". Taken together, these data illustrate biomedical opportunities made possible by engineering tools of EPT into multilayered polymer coatings and present a novel, highly versatile tool for surface mediated drug delivery.

Quercetin, but not its metabolite quercetin-3-glucuronide, exerts prophylactic immunostimulatory activity and therapeutic antiinflammatory effects on lipopolysaccharide-treated mouse peritoneal macrophages ex vivo

This study investigated the prophylactic or therapeutic effects of quercetin (Q) and its metabolite quercetin-3-glucuronide (Q3G) on lipopolysaccharide (LPS)-induced inflammation in mouse peritoneal macrophages ex vivo. Changes in pro- and antiinflammatory cytokine secretion profiles were determined. The results showed that Q or Q3G in vitro treatments lower than 50 μM did not exhibit cytotoxicity on macrophages. At noncytotoxic doses, Q and Q3G, particularly Q, administration in a prophylactic ex vivo model increased pro-/antiinflammatory cytokine secretion ratios by macrophages in the absence or presence of LPS. Quercetin, but not Q3G, administration in a therapeutic ex vivo model decreased pro-/antiinflammatory cytokine secretion ratios in the absence or presence of LPS. Our results indicated that Q and Q3G administrations in a prophylactic manner might act as an immunostimulatory agent, but Q presented better ability than Q3G. Quercetin might have a therapeutic, but not prophylactic, effect on spontaneous or LPS-induced inflammation in vivo.

Quercetin and quercetin 3-O-glycosides from Bauhinia longifolia (Bong.) Steud. show anti-Mayaro virus activity

Background

The arthropod-borne Mayaro virus (MAYV) causes ‘Mayaro fever’, a disease of medical significance, primarily affecting individuals in permanent contact with forested areas in tropical South America. Recently, MAYV has attracted attention due to its likely urbanization. Currently, there are no licensed drugs against most mosquito-transmitted viruses. Here, we investigated the in vitro anti-MAYV activity of the flavonoids quercetin and its derivatives from the Brazilian shrub Bauhinia longifolia (Bong.) Steud.

Methods

Flavonoids were purified by chromatographic fractionation from leaf extracts of B. longifolia and chemically identified as quercetin and quercetin glycosides using spectroscopic techniques. Cytotoxicity of purified flavonoids and of EtOAc- and n-BuOH-containing flavonoid mixtures was measured by the dye-uptake assay while their antiviral activity was evaluated by a virus yield inhibition assay.

Results

The following flavonoids were purified from B. longifolia leaves: non-glycosylated quercetin and its glycosides guaijaverin, quercitrin, isoquercitrin, and hyperin. EtOAc and n-BuOH fractions containing these flavonoids demonstrated the highest antiviral activity of all tested substances, while quercetin had the highest antiviral activity amongst purified flavonoids. Quercetin, EtOAc, or n-BuOH fractions inhibited MAYV production by more than 90% at 25 μg/mL, displaying a stronger antiviral effect than the licensed antiviral ribavirin. A mixture of the isomers isoquercitrin and hyperin had a modest antiviral effect (IC₉₀ = 104.9), while guaijaverin and quercitrin did not show significant antiviral activity.

Conclusions

B. longifolia is a good source of flavonoids with anti-Mayaro virus activity. This is the first report of the activity of quercetin and its derivatives against an alphavirus.

Identification and quantitative analysis of polyphenolic compounds from the indigo plant (Polygonum tinctorium Lour)

The indigo plant (Polygonum tinctorium Lour) has been used traditionally as a medicinal plant with a variety of biological effects. Of these, polyphenolic ingredients are postulated to contribute to these activities. However, the identification and quantification of polyphenolic compounds in indigo plants have not been conducted comprehensively until now. This study was undertaken to identify the related ingredients by combined instrumental analyses using ultra-performance liquid chromatography electrospray-ionisation mass spectrometry and gas chromatography-mass spectrometry after the extracts of plant tissues were fractionated by absorption column chromatography. These analyses allowed the identification of kaempferol, quercetin-3-O-glucuronide, quercetin, kaempferol-3-O-glucopyranoside, caffeic acid, chlorogenic acid and tentative 3,5,4'-trihydroxy-6,7-methylenedioxyflavone. Furthermore, predominant polyphenolic compounds were quantified by reverse-phase high-performance liquid chromatography and capillary gas chromatography, revealing the higher proportions of kaempferol, quercetin-3-O-glucuronide and quercetin among them. The results indicate that the indigo plant is a promising source for flavonoids and the related compounds with beneficial medicinal effects.

Studies on chromatographic fingerprint and fingerprinting profile-efficacy relationship of polygoni perfoliati herba

Polygoni Perfoliati Herba is widely used in China with antibacterium, anti-inflammatory, expectorant, antitumor, and antivirus activities. To reveal the mechanisms of the activities of Polygoni Perfoliati Herba, the relationship between the fingerprinting profile and its bioactivities was investigated. In the present study, high-performance liquid chromatographic (HPLC) fingerprinting method was developed. The established method was applied to analyze 51 batches of Polygoni Perfoliati Herba samples collected from different locations or in different harvesting times in China. Chemometrics, including similarity analysis, hierarchical clustering analysis, and principal component analysis, were used to express their similarities. It was found that similarity values of the samples were in the range of 0.432–0.998. The results of analgesic tests indicated that Polygoni Perfoliati Herba could significantly inhibit pain induced by hot plate and acetic acid in mice. The results of anti-inflammatory tests showed that Polygoni Perfoliati Herba had good anti-inflammatory effects (P < 0.01) in two models including dimethyl benzene-induced ear edema and acetic acid-induced peritoneal permeability in mice. Combining the results from chromatographic fingerprints with those from bioactivities, we found that seven peaks from Polygoni Perfoliati Herba were mainly responsible for analgesic and anti-inflammatory activities.

Antioxidant and anti-inflammatory flavonol glucuronides from Polygonum aviculare L

A series of 11 flavonol glucuronides were isolated from the herb of Polygonum aviculare L. (Ph.Eur) of which 8 were reported for the first time from the Polygonum species. Three acetylated kaempferol and isorhamnetin glucuronides were isolated from a natural source for the first time. All compounds, including the new ones, were characterized using 1D and 2D NMR spectra as well as high resolution mass spectrometry. The influence of all isolated compounds on the production of reactive oxygen species, as well as on elastase release by human neutrophils, was evaluated in in vitro studies. The results showed that all investigated compounds at physiologically achievable concentrations within the range of 0.5-10 μM significantly inhibited the production of reactive oxygen species as well as elastase release in human neutrophils model and should be considered as responsible for anti-inflammatory activity of the P. aviculare herb. The chemotaxonomic value of isolated compounds was also discussed.

Screening of biological activities of Polygonum maritimum L. from Algerian coast

OBJECTIVE

To investigate the antioxidant and the antibacterial activities of crude extract from aerial part of Polygonum maritimum L. (Polygonaceae) (P. maritimum) and to find new actives biomolecules.

METHODS

The whole plant was collected from the Rechgoune coast (West of Algeria), and methanolic crude extract of aerial parts of P. maritimum (PMCE) was prepared. The extract was tested against different bacterial strain and tested for his ability to neutralize free radical (DPPH) and to scavenge the H2O2.

RESULTS

PMCE had a very high content of total phenol, which was (352.49±18.03) mg/g dry weight, expressed as gallic acid equivalent. PMCE exhibited excellent antioxidant activity, as measured using DPPH and H2O2 scavenging assays. It also showed a high antibacterial activity against gram-positive bacterial strains: Bacillus cereus, Bacillus subtilis and Staphylococcus aureus with an highest MIC of 120 µg/mL.

CONCLUSIONS

The antioxidant and antibacterial activity of the PMCE is probably due to phenolic compounds present in the extract. The contemporary presence of antioxidant and antibacterial activities in the PMCE suggests that this plant may be a source of bioactive substances with multifaceted activity.

Quantitative and chemical fingerprint analysis for the quality evaluation of Receptaculum Nelumbinis by RP-HPLC coupled with hierarchical clustering analysis

A simple and reliable method of high-performance liquid chromatography with photodiode array detection (HPLC-DAD) was developed to evaluate the quality of Receptaculum Nelumbinis (dried receptacle of Nelumbo nucifera) through establishing chromatographic fingerprint and simultaneous determination of five flavonol glycosides, including hyperoside, isoquercitrin, quercetin-3-O-β-d-glucuronide, isorhamnetin-3-O-β-d-galactoside and syringetin-3-O-β-d-glucoside. In quantitative analysis, the five components showed good regression (R > 0.9998) within linear ranges, and their recoveries were in the range of 98.31%–100.32%. In the chromatographic fingerprint, twelve peaks were selected as the characteristic peaks to assess the similarities of different samples collected from different origins in China according to the State Food and Drug Administration (SFDA) requirements. Furthermore, hierarchical cluster analysis (HCA) was also applied to evaluate the variation of chemical components among different sources of Receptaculum Nelumbinis in China. This study indicated that the combination of quantitative and chromatographic fingerprint analysis can be readily utilized as a quality control method for Receptaculum Nelumbinis and its related traditional Chinese medicinal preparations.

Novel insight into qualitative standardization of Polygoni avicularis herba (Ph. Eur.)

Polygonum aviculare L. (Common Knotrgrass) (Polygonaceae Juss.) is an annual from which pharmacopoeial (Ph. Eur.) plant material Polygoni avicularis herba is obtained. Although its main active constituents are flavonoids and its standardization is based on their total content, no profound qualitative analysis has been performed, yet. The use of hyphenated analytical methods: UHPLC-DAD coupled with ion trap or time of flight mass detectors together with acidic hydrolysis products analysis allowed for a comprehensive determination of flavonoid composition. Among dominating compounds, myricetin, kaempferol, isorhamnetin and kaempferide glucuronides, which were not previously reported in P. avicularis herba, were discovered. The developed method can be used as a suitable tool for a more insightful, metabolome-based standardization of flavonoid rich pharmacopoeial plant material -P. avicularis herba.

Development of a quercetin-loaded nanostructured lipid carrier formulation for topical delivery

The main objective of this study was to evaluate the potential of quercetin-loaded nanostructured lipid carriers (QT-NLCs) as a topical delivery system. QT-NLCs were prepared by the method of emulsion evaporation-solidification at low temperature. The average entrapment efficiency and drug loading of the optimized QT-NLCs were 89.95 ± 0.16% and 3.05 ± 0.01%, respectively. Under the transmission electron microscope, the nanoparticles were spherically shaped. The average particle size was 215.2 nm, the zeta potential was -20.10 ± 1.22 mV and pH value of QT-NLCs system was 4.65. Topical delivery of QT in the form of NLCs was investigated in vitro and in vivo. The results showed that QT-NLCs could promote the permeation of QT, increase the amount of QT retention in epidermis and dermis, and enhance the effect of anti-oxidation and anti-inflammation exerted by QT. Then the mechanism of NLCs for facilitating drug penetration was further investigated through histological sections. In conclusion, NLCs could be a promising vehicle for topical delivery of QT.