Accumulation of Polyphenolic Compounds and Osmolytes under Dehydration Stress and Their Implication in Redox Regulation in Four Indigenous Aromatic Rice Cultivars

Present work was undertaken to screen some drought tolerant indigenous aromatic rice cultivars(IARCs),commonly cultivated in West Bengal,India,based on their capacity to produce osmolytes,redox-sensitive phenolic acids and flavonoids,as contrivances for redox-regulation under drought stress.Polyethylene glycol induced post imbibitional dehydration stress mediated changes in redox regulatory properties of the germinating seeds of the four IARCs(Jamainadu,Tulaipanji,Sitabhog,Badshabhog),which were assessed in terms of changes in prooxidant accumulation(in-situ localization of reactive oxygen species(ROS)by confocal microscopy,DCFDA(2′,7′-dichlorofluorescin diacetate)oxidation,O2-and H2O2 accumulation),cumulative antioxidative defense(radical scavenging property and total thiol content),ROS scavenging phenolic acids(gallic acid,protocatechuic acid,gentisic acid,para-hydroxy benzoic acid,chlorogenic acid,caffeic acid,syringic acid,salicylic acid,sinapic acid and p-coumaric acid)and flavonoids(catechin,naringin,rutin,quercetin,kaempferol,myricetin and apigenin).The capability of germinating seeds to accumulate osmolytes(like glycinebetaine,proline,soluble carbohydrates and K+ion)and polyphenolic compounds was also correlated with their corresponding redox status and redox biomarkers(conjugated diene,hydroperoxide,thiobarbituric acid reactive substances and free carbonyl content)produced under the same conditions.The results in general showed that accumulation of osmolytes along with the redox-sensitive phenolics and flavonoids conferred the ability to maintain the redox homeostasis under drought stress for the tolerant IARCs(Badshabhog and Tulaipanji).

Phytochemical characterization of polyphenolic compounds with HPLC–DAD–ESI–MS and evaluation of lipid-lowering capacity of aqueous extracts from Saharan plant Anabasis aretioides(Coss & Moq.) in normal and streptozotocin-induced diabetic rats

Objective： Anabasis aretioides （Coss ＆ Moq.）, a Saharan plant belonging to Chenopodiaceae family, is widely distributed in semi-desert areas from the Tafilalet region of Morocco. This plant is extensively used by local population against diabetes and cardiovascular disorders. The purpose of the study was to investigate the effect of the aqueous A. aretioides extract on lipid metabolism in normal and strepto-zotocin （STZ）-induced diabetic rats and to identify the polyphenolic compounds present. In addition, the in vitro antioxidant activity of the aqueous A. aretioides extract was also evaluated. Methods： The effect of an aerial part aqueous extract （APAE） ofA. aretioides （5 mg/kg of lyophilized A. are-tioides APAE） on plasma lipid profile was investigated in normal and STZ-induced diabetic rats （n = 6） after once daily oral administration for 15 days. The aqueous extract was tested for its 1,1-diphenyl-2-picrylhydrazyl （DPPH） radical-scavenging activity. Polyphenolic compounds in the extracts were defini-tively characterized by high-performance liquid chromatography-diode array detection-electrospray ionization-mass spectrometry. Results： In diabetic rats, oral administration ofA. aretioides APAE provoked a significant decrease in both plasma cholesterol and triglyceride levels from the first to the second week （P 〈 0.01）. A significant decrease on plasma triglyceride levels was also observed in normal rats （P 〈 0.01）, where the reduction was 53%. In addition, the phytochemical analysis revealed the presence of 12 polyphenolic compounds. Moreover, according to the DPPH radical-scavenging activity, the aqueous extract showed an in vitro antioxidant activity. Conclusion： Aqueous A. aretioides APAE exhibits lipid-lowering and in vitro antioxidant activities. Many polyphenols were present in this extract and these phytoconstituents may be involved in the pharmaco-logical activity of this plant.

Polyphenolic Compound and the Degree of Browning in Processing Apple Varieties

Polyphenolic compound in processing apple （Malus domestica Borkh.） varieties and the relationship between polyphenol content and enzymatic browning were studied to provide reference for raw material selection and processing method optimization. The content of polyphenol compound in 10 processing apple varieties （4 cider and 6 juice varieties） were analyzed using the Folin-Ciocalteu method and HPLC. The degree of browning and the activities of polyphenol oxidase were also studied. The content and proportion of the polyphenol varied depending on the variety. Bitter varieties globally showed a higher polyphenol concentration than sweet or acid varieties. Proanthocyanidins, chlorogenic acid, （＋）-catechin, （-）-epicatechin were high-concentrated polyphenols in apple fruits. Phloridzin, the unique polyphenol of apple, was abundant in the bitter variety Frequin rouge fruit. Total polyphenols, proanthocyanidins, （＋）-catechin, and phloridzin had higher correlations with browning. The correlation was low between chlorogenic acid and browning. The polyphenolic profiles were correlated with the apple types. Cider apples contained more polyphenol than juice apple varieties. The content of flavan-3-ol has a close relationship with fruit browning.

Polyphenolic content, in vitro antioxidant activity and chemical composition of extract from Nephelium lappaceum L.(Mexican rambutan) husk

Objective: To determinate the recovery of total polyphenolic compounds content,in vitro antioxidant activity and HPLC/ESI/MS characterization of extract from Nephelium lappaceum L.(Mexican rambutan).Methods: The rambutan husk extract was obtained by aqueous extraction and a polyphenolic fraction was recovered using Amberlite XAD-16. The total polyphenolic compounds content was determined by the Folin Ciocalteu and butanol-HCI methods.In vitro antioxidant activity was performed using ABTS and ferric reducing antioxidant power methods.Results: Mexican rambutan husk showed a total polyphenolic content of 582 mg/g and an evident antioxidant activity by ABTS and ferric reducing antioxidant power analysis.The HPLC/ESI/MS assay allowed the identification of 13 compounds, most of which belong to ellagitannins. Geraniin, corilagin and ellagic acid were present in the sample;the mineral composition was also evaluated.Conclusions: Rambutan husk cultivated in Mexico is a promising source for the recovery of added value bioactive compounds with antioxidant activity, which have potential applications as bioactive antioxidant agents for the treatment of diseases.

Exploring the mechanism of hypolipidemic effect of polyphenols in wolfberry based on network pharmacology and molecular docking

To explore the mechanism of hypolipidemic action of wolfberry polyphenols by using network pharmacology and molecular docking.The active ingredients and targets of wolfberry were searched by TCMSP,and the Cytoscape 3.9.0 software was used to construct a“wolfberry component-target”network.The Gene Cards database was used to screen the hyperlipidemic targets and intersect them with the active targets of wolfberry to construct the PPI network using the STRING platform.The gene ontology(GO)function and Kyoto encyclopedia of genes and genomes(KEGG)pathway enrichment analysis of the core targets were carried out on the Metascape platform,and molecular docking of the active ingredients to the core targets was performed using AutoDockTools software.A total of 33 active ingredients and 173 potential targets of wolfberry were screened,including 99 targets related to hyperlipidemia.The results of the analysis of 99 intersecting targets with the components of wolfberry identified the core active ingredients as quercetin,glycitein and atropine.The binding of the major components of wolfberry,including the polyphenolic compounds quercetin and glycitein,as well as atropine to the key targets AKT1,IL6 and TNF may be important mechanisms for the hypolipidemic therapeutic effect.GO functional enrichment analysis involves biological processes,cellular components,and molecular functions.The KEGG pathway enrichment analysis mainly involves the AGE-RAGE signaling pathway,fluid shear stress,and TNF signaling pathway.Molecular docking validated the good binding activity of the targets to the active ingredients.The binding of atropine and the polyphenolic compounds quercetin and glycitein to the key targets AKT1,IL6 and TNF may be an important mechanism for the hypolipidemic therapeutic effect of wolfberry.

A Comparative Study on Pharmacokinetics of Tricin, a Flavone from Gramineous Plants with Antiviral Activity

Tricin (and tricin containing plant extracts) has been shown to exert a pronounced antiviral activity, high radical scavenging activity and is favored for its safety profile. In the present study we have analyzed the pharmacokinetics of tricin after a single intravenous and oral administration to Wistar rats of an ethanol extract of Calamagrostis Adans and Deschampsia Beauv plants (test agent) at different doses. Tricin concentrations in blood plasma and blood cells were measured at different time points. Two-compartment (for intravenous injection) and one compartment (for oral administration) models were used for the analysis of tricin pharmacokinetics. The results showed that the pharmacokinetics of tricin after intravenous injection of test agent has a pronounced biphasic character, is well described by a two-compartment pharmacokinetic model, and is characterized by non-linear dose-dependence. The pharmacokinetics of tricin administered orally is characterized by a high rate of absorption from the gastrointestinal tract into the blood and rather slow elimination, which leads to a large volume of distribution in the body and a fairly high bioavailability. The obtained results indicate the advantages of the oral route of administration over the intravenous route.

Potential of polyphenols in curbing quorum sensing and biofilm formation in Gramnegative pathogens

Polyphenols are the secondary metabolic products of plants and are considered as active constituents to possess therapeutic effects.To date,a vast number of scientific literature addressed the potential of polyphenols as bio-efficient compounds owing to their structural diversity.Due to the presence of several hydroxyl groups,they are metabolized quickly due to conjugation reaction and thus,readily produce toxic metabolites as a defense material against many pathogens,reflecting their safety strategy.This review focuses on the anti-quorum sensing and biofilm inhibition activity of polyphenols,which display their potential to treat bacterial infections by combating the virulence caused by pathogenic agents.Thus,for mitigating quorum sensing-controlled pathogenesis,the use of polyphenol-based phytochemicals holds immense potential to cure infections.The application of polyphenol as sensitizing agent/adjuvant therapeutics which act in synergism with antibiotics is highly remarkable.

Health promoting activities and corresponding mechanism of(–)-epicatechin-3-gallate

(–)-Epicatechin-3-gallate(ECG),a bioactive polyphenolic compound,has contributed a lot to the health benefits of green tea.Great attention has been focused on(–)-epigallocatechin-3-gallate(EGCG),but limited research has been performed towards ECG.Like EGCG,ECG also possesses various pharmacological and physiological properties,such as mediation of antioxidant activities,anti-inflammation response,regulation of cell proliferation and apoptosis,as well as anticancer properties during angiogenesis,invasion and metastasis stages.Nontoxic ECG has various molecular targets within the cells,including CYP enzymes,phaseⅡdetoxification and antioxidant enzymes,as well as pro-inflammatory mediators.The antineoplastic mechanism contains inhibition of phase 1 CYP enzymes,induction of phaseⅡdetoxification and antioxidant enzymes,high anti-inflammatory efficacy,arrest of cell cycle progression,regulation of apoptosis,as well as mediation of metastasis processes.In particular,the gallate moiety of ECG is critical for mediating inhibitory effects towards cancer cells.Besides regulation of intracellular signaling pathways,ECG also inhibits RNase A and matrix metalloproteinase enzymatic activity via chelating metals(copper and zinc)in cancer cells.This review has summarized recent studies on pharmacological properties of ECG,and discussed corresponding mechanism on modulation of cellular signaling events by ECG,hoping to broaden its multiple usage.

Determination of the Contents of Seven Chemical Components in Vidal Grape by Quantitative Analysis of Multi-components by Single Marker(QAMS)

[Objectives]This study was conducted to establish a method of quantitative analysis of multi-components by single marker(QAMS)for the simultaneous determination of such seven chemical components as gallic acid,epicatechin,catechin,ferulic acid,chlorogenic acid,rutin and caffeic acid in Vidal grape.[Methods]The high performance liquid chromatography was carried out using a COSMOSIL C18-MS-II column(4.6 mm×250 mm,5μm)with the mobile phase acetonitrile-2%acetic acid aqueous solution(gradient elution)at a flow rate of 1.0 ml/min.The detection wavelength was 280 nm,and the column temperature was 25℃.Using caffeic acid as an internal reference,the relative correction factors between it and other six to-be-detected components,and the contents of the seven components were calculated using the correction factors.The established was compared the results with the external standard method to verify the feasibility and accuracy of the method.[Results]The seven components had a good linear relationship in the ranges of 1.060-10.60,1.419-14.19,1.062-10.62,0.2950-2.950,0.1019-1.019,0.2014-2.014,and 0.1498-1.498μg,respectively,and the relative correction factors of gallic acid,epicatechin,catechin,ferulic acid,chlorogenic acid and rutin were 0.9760,0.7806,0.3277,1.640,1.161,2.778,respectively.There was no significant difference between the results of the QAMS method and the external standard method.[Conclusions]The QAMS method using caffeic acid as an internal reference is accurate and feasible,and provides a reliable method for the quality evaluation of Vidal ice grape.

Nutritional and Anti-Nutrient Composition of Three Kola Nuts(Cola nitida,Cola acuminata and Garcinia kola)Produced in Benin

Kola nuts were regularly chewed by West Africans and Beninese in particularly. The aim of this study was to investigate nutritional and anti-nutrient content of three Benin’s kola nuts (Cola nitida, Cola acuminata and Garcinia kola). Proximate composition of the three species of kola nuts was assessed using standard analytical AOAC methods. Phenolics and flavonoids contents were determined by Folin-Ciocalteu and aluminum trichloride methods, respectively. Mineral composition was determined by Atomic Absorption Spectrometry method. Free and total amino acids were separated and quantified by HPLC. Protein content of the three kola nuts ranges from 4.95% (G. kola) to 10.64% (C. acuminata) whereas fat content ranges from 0.2 ± 0.00 (C. nitida) to 2.5 ± 0.42 (G. kola). Total phenolics abounded (2444.96 ± 81.56 μg Eq AG/100g) in C. acuminata, while flavonoids predominated (561.69 ± 22.10 μgEqQ/100g) in G. kola. The three species are a good source of magnesium and a copper provider was lowest in C. nitida (0.59 ± 0.08 mg/g) and in C. acuminata (0.65 ± 0.02 mg/g). The dominant total essential amino acids were threonine (C. acuminata) and methionine (C. acuminata and G. kola), while the predominant non-essential total amino acids according to species were arginine (C. nitida and G. kola), proline (C. acuminata) and cysteine (G. kola). For the anti-nutrients factors, saponins were in great proportion (8.33% ± 0.25%), while the oxalates were in small proportion (0.44% ± 0.04%). The three species have an interesting nutritional composition, but these seeds have the relatively lowest amino acids content.

Total phenolic compounds,antioxidant potential and α-glucosidase inhibition by Tunisian Euphorbia paralias L.

Objective:To examine the potential antioxidant and anti-α-glucosidase inhibitory activities of Tunisian Euphorbia paralias L.leaves and stems extracts and their composition of total polyphenol and flavonoids.Methods:The different samples were tested for their antiradical activities by using 2,2’-azinobis(3-ethylbenzothiazoline-6-sulfonic acid)(ABTS)and 1,1-diphenyl-2-picrylhydrazyl(DPPH)assays.Inα-glucosidase activity,α-glucosidase(0.3 IU/mL)and substrate,2500μmol/L p-nitrophenylα-D-glucopyranoside were used;absorbance was registered at 405 nm.Results:The leaves acetonic extract exhibited the strongestα-glucosidase inhibition[IC_(50)=(0.0035±0.001)μg/mL],which was 20-fold more active than the standard product(acarbose)[IC_(50)=(0.07±0.01)μg/mL].Acetonic extract of the leaves exhibited the highest quantity of total phenolic[(95.54±0.04)μg gallic acid equivalent/mg]and flavonoid[(55.16±0.25)μg quercetin equivalent/mg].The obtained findings presented also that this extract was detected with best antioxidant capacity[IC_(50)=(0.015±0.01)μg/mL]against DPPH and a value of IC_(50)equal to(0.02±0.01)μg/mL against ABTS.Positive relationship between polyphenolic content of the tested Euphorbia paralias L.leaves and stems extracts and its antioxidant activity(DPPH and ABTS)was detected.Elevated positive linear correlation was got between ABTS and total phenolic(R^(2)=0.751).Conclusions:The findings clearly demonstrate that the use of a polar solvent enables extraction of significant quantities of phenol compounds and flavonoids.

Red osier dogwood and its use in animal nutrition:A review

As the human population increases globally,the food animal industry has not been spared from the monumental demand for edible animal products,particularly meat.This has necessitated the simulta-neous expansion of the productivity of the animal sector to meet the ever-growing human needs.Although antibiotics have been used in food animal production with commendable positive impacts on their growth performance,their sole contributive factor to the increasing incidence of antimicrobial resistance has ushered the strict restrictions placed on their use in the animal sector.This has handed a setback to both animals and farmers;thus,the intense push for a more sustainable antibiotic alternative for use in animal production.The use of plants with concentrated phytogenic compounds has gained much interest due to their beneficial bioactivities,including antioxidant and selective antimicrobial.While the reported beneficial activities of phytogenic additives on animals vary due to their varying total polyphenol concentrations(TPC),red osier dogwood(ROD)plant materials boast of high TPC with excellent antioxidant prowess and growth improvement capacities compared to some plant extracts commonly used in research.However,its adoption in research and commercial scale is still low.Thus,the present review aims to provide concise information on the dietary potential of ROD plant materials in animal feeding.