Flavonoids

RATIONALE: Agarwood is the resinous material harvested from threatened Aquilaria species. We investigated how many protonated 2-(2-phenylethyl)chromone ions were sufficient to make an accurate identification of agarwood. Analysis of 125 reference samples was carried out by direct analysis in real time time-of-flight mass spectrometry (DART-TOFMS). The identification criteria developed were applied to commercial samples. METHODS: We developed a technique that uses DART-TOFMS to detect 2-(2-phenylethyl)chromones. Additionally, we developed a set of criteria to infer the presence of Aquilaria in commercial samples of wood chips, sawdust, incense and liquids. Additionally, we examined other fragrant woods to determine if they contained a chemical profile that could be falsely identified as agarwood. RESULTS: Analysis of reference and commercial samples (n = 151) established that DART-TOFMS provides reproducible mass spectra that are useful for inferring the genus of suspected agarwood samples. We identified 17 ions which were useful for authenticating agarwood. Comparison of the number of chromone ions detected by direct analyses of dry wood chips versus eluent analysis of methanol-extracted wood showed that results were similar. Lastly, analysis of 25 scented woods of other species did not give false positive results. CONCLUSIONS: Reliable criteria for inferring agarwood include the presence of diagnostic ions, m/z 319.118 or 349.129, in addition to ten or more ions characteristic of 2-(2-phenylethyl)chromones. Wood anatomists challenged with difficult morphological identifications can use this tool to assist in their analyses. Published 2012. This article is a US Government work and is in the public domain in the USA.

Context: Flavonoids are natural polyphenolic compounds that are ubiquitous in plants. Numerous prospective epidemiological studies have found beneficial effects of flavonoid consumption on overall cardiovascular mortality. These effects have been attributed to nonspecific antioxidant, anti-atherosclerotic and antithrombotic properties of flavonoids. However, little is known about direct actions of flavonoids on cardiac and vascular smooth muscles.

Aims: To evaluate the effects of three flavonoids (naringenin, quercetin and genistein) on electrical and contractile activities of isolated rat hearts and on contraction of rat abdominal aortic rings.

Methods: Surface electrogram (ECG) and force of contraction (FC) were recorded in isolated rat hearts. The ventricular fibrillation threshold was evaluated with the flavonoids. The effects on aortic contraction were assessed in rat abdominal aortic rings pre-contracted with 60 mM of KCl.

Results: Genistein tended to prolong the QT interval while naringenin tended to decrease it. The effects of all flavonoids on QRS and RR interval were mild and not statistically significant. Genistein and naringenin produced a negative inotropic effect in isolated rat hearts with an IC50 of 13.8 μM and 33.8 μM, respectively. Quercetin at low concentrations had a positive inotropic effect; at high concentrations, it exerted a negative inotropic effect. Naringenin and quercetin increased the threshold for ventricular fibrillation, whereas genistein decreased it. Naringenin, quercetin, and genistein induced concentration-dependent relaxation in endothelium-denuded rat aortic rings.

Conclusions: These flavonoids have direct actions on rat cardiac and vascular smooth muscles.

Resveratrol is a natural molecule with antioxidant action. Moreover, resveratrol is also considered to be a molecule with anti-inflammatory action, an effect attributed to suppression of prostaglandin (PG) biosynthesis. The aim of the present study was to investigate the effects of resveratrol, a polyphenol present in most red wines, on reactive oxygen species formation as well as on arachidonic acid (AA) release, cyclooxygenase expression, and PG synthesis in murine resident peritoneal macrophages. Results show that resveratrol exerted a strong inhibitory effect on superoxide radical (O2−) and hydrogen peroxide (H2O2) produced by macrophages stimulated by lipopolysaccharides (LPS) or phorbol esters (PMA). Resveratrol also significantly decreased [3H]AA release induced by LPS and PMA or by exposure to O2− or H2O2. Resveratrol treatment caused a significant impairment of cyclooxygenase-2 (COX-2) induction stimulated by LPS and PMA or by O2− or H2O2 exposure. These effects of resveratrol on [3H]AA release and COX-2 overexpression were correlated with a marked reduction of PG synthesis. Our results indicate that the antioxidant action of resveratrol affects AA mobilization and COX-2 induction.

A simple and sensitive high-performance liquid chromatography method for the determination of four Leuzea carthamoides flavonoids, namely eriodictyol, patuletin, eriodictyol-7-β βglucopyranoside, and 6-hydroxykaempferol-7-O-(6"-O-acetyl-β β-Dglucopyranoside), is presented. Using this method, quantitative composition of flavonoids ranged from 0.011% to 0.574% in dried plant material was determined. This method could be used in the future for the quantitative evaluation of major phenolic compounds in L. carthamoides.

It was investigated the effect of particle size, use of infrared radiation, and type of freeze-drying (vacuum or atmospheric) on some nutritional properties of blueberries. Particle size and type of freeze-drying had negative effects on ascorbic acid and total polyphenols content, while the use of infrared radiation had positive effects on them. Particle size negatively affected antioxidant activity. Ascorbic acid was significantly decreased in freeze-dried blueberries compared to fresh fruit, in all the conditions studied. The total polyphenols content was significantly lower in atmospheric freezedried blueberries compared to the fresh ones, unlike in vacuum freeze-drying, where this nutritional property was increased. Antioxidant activity of freeze-dried blueberries did not differ significantly from that found in fresh fruits. In order to minimize the impairment of the nutritional properties of freeze-dried blueberries, it is suggested to use infrared radiation, a relatively small particle size and vacuum freeze-drying.

Research has shown that numerous dietary bioactive components that are not considered essential may still be beneficial to health. The dietary reference intake (DRI) process has been applied to nonessential nutrients, such as fiber, yet the majority of bioactive components await a recommended intake. Despite a plethora of new research over the past several years on the health effects of bioactives, it is possible that the field may never reach a point where the current DRI framework is suitable for these food components. If bioactives are to move toward dietary guidance, they will likely require an alternative path to get there.

Plant-derived phenolic compounds, including polyphenols (e.g., tannins), flavonoids, and phenolic acids, have been under investigation for their anticancer therapeutic and chemoprevention properties. Recently, certain mechanisms underlying the differential effects of GTPPs on tumor versus normal cells have been determined. These suggest that GTPPs may simultaneously activate multiple pathways. However, existing screening methods are insufficient for the identification of agents that possess both a cytotoxic effect on tumor cells and a protective effect on normal cells. The current study describes the establishment of an in vitro survival/apoptosis testing system based on detecting these mechanisms by a double-fluorescence method. This system is able to screen potential chemopreventive or therapeutic agents from (but not limited to) plant-derived compounds based on the pathways differentially activated by the agents. Tumor cell death and normal cell survival are detected simultaneously, in a device that co-cultures normal human cells adjacent to human tumor cells.

Mode of interactions of three flavonoids [morin (M), quercetin (Q), and rutin (R)] with chicken blood ds.DNA (ck.DNA) has been investigated spectrophotometrically at different temperatures including body temperature (310 K) and at two physiological pH values, i.e. 7.4 (human blood pH) and 4.7 (stomach pH). The binding constants, K f , evaluated using Benesi-Hildebrand equation showed that the flavonoids bind effectively through intercalation at both pH values and body temperature. Quercetin, somehow, showed greater binding capabilities with DNA. The free energies of flavonoid-DNA complexes indicated the spontaneity of their binding. The order of binding constants of three flavonoids at both pH values were found to be K f(Q) > K f(R) > K f(M) and at 310 K.

Phyllanthus sellowianus Müller Arg. (Euphorbiaceae) is a plant used in folk medicine as a hypoglycemic and diuretic agent. The present study describes the hypoglycemic effect of fractions obtained from the stem barks of P. sellowianus using a bioassay-guided fractionation protocol and streptozotocin-induced hyperglycemic mice. The aqueous extract was partitioned between dichloromethane and butanol to yield the dichloromethane (D), butanol (B) and the remaining aqueous (A) fractions. Fractions B and A, administered at the dose of 200 mg/kg p.o., caused a significant reduction in blood glucose concentration at 6 and 9 h, while the same dose of fraction D was ineffective. The reduction in blood glucose levels obtained with the B and A fractions was similar to that observed with glibenclamide (10 mg/kg) which was used as a reference for the hypoglycemic activity. Phytochemical analysis of fractions B and A revealed the presence of flavonoid compounds, of wich rutin and isoquercitrin were the major constituents, respectively. The possible involvement of these flavonoids in the hypoglycemic effect of the active fractions is discussed.

Cereals are an important part of diets for hypercholesterolemic patients. However, some of these patients are allergic to these natural products. The purpose of the current study was to compare oatmeal with equal in nutritional values two allergy-free amaranth meals to determine whether this pseudocereal can be a substitute for allergic to cereals individuals. The total phenols of the samples were determined with the Folin-Chocalteu reagent, anthocyanins, and flavonoids spectrophotometrically. The antioxidant activities were estimated with nitric oxide scavenging radical (NO) and by ␤-carotene bleaching (␤-carotene). It was found that the contents of different protein fractions, antioxidant compounds, and the antioxidant activities of oatmeal were significantly higher than those of the two amaranth samples. The results of kinetic reactions showed that samples differed in their capacities to quench these radicals, and oats have shown more antioxidant activity than amaranth. High correlation was observed between antioxidant activities and phenols (R 2 ϭ 0.99). In the in vivo part of the investigation, 60 male Wistar rats were divided into five diet groups of 12 animals each; these groups were designated as Control, Chol, Chol/Oat, Chol/AmarI, and Chol/AmarII. The rats of the Control group were fed basal diet (BD) only. To the BD of the four other groups were added the following: 1% of cholesterol (Chol), 10% of oat meal and 1% of cholesterol (Chol/Oat), 10% of amaranth I meal, and 1% of cholesterol (Chol/AmarI) and 10% of amaranth II meal and 1% of cholesterol (Chol/AmarII). After 32 days of different feeding, diets supplemented with oat meal and, to lesser degree, with amaranth I and amaranth II hindered the rise in the plasma lipids: a) TC: 3.14 vs. 4.57 mmol/L, Ϫ 31.3%; 3.31 vs. 4.57 mmol/L Ϫ 27.6%; and 3.40 vs. 4.57, Ϫ 25.6%, respectively b) LDL-C: 1.69 vs. 3.31 mmol/L, Ϫ 49.9%; 2.05 vs. 3.31 mmol/L, Ϫ 38.1%; and 2.16 vs. 3.31 mmol/L, Ϫ 34.8%, respectively; c) TG: 0.73 vs. 0.88 mmol/L, Ϫ 17.1%; 0.75 vs. 0.88 mmol/L, Ϫ 14.8%; and 0.79 vs. 0.88 mmol/L, Ϫ10.2%, respectively. The HDL-PH was increased as follows: 0.79 vs. 0.63 mmol/L, Ϫ25.3%; 0.75 vs. 0.63 mmol/L, Ϫ23.0%; and 0.71 vs. 0.63 mmol/L, Ϫ12

To establish the anti-platelet or aspirin like effects of flavonoid rich food (chocolate). Methods: This was a non-randomized quasi experimental study in which, 65 healthy adult volunteers, 27 males and 38 females, participated. The subjects included were healthy, non-smoking adults. Health of subjects was evaluated by a questionnaire for which a written informed consent was taken prior to admission in the study. Research protocol was approved by the college's, "Research and Ethical committee". Division of subjects into two groups, a control group which consumed 100mgs of oral aspirin and an interventional group consuming 100mgs oral aspirin and 18.75gms of dark chocolate (flavonoid rich), was carried out. The Bleeding time estimation for both the groups was done by "Duke Method" of bleeding time estimation. Results: Data was analyzed by SPSS 15.0. First, a bivariate analysis was done by comparing both the pre-test groups i.e. before consumption of aspirin and also before consumption of chocolate and aspirin together through independent t-test Later, regression analysis was also done. Bivariate analysis compared both the control and interventional groups. After comparing pre-test groups a p-value of 0.798 was obtained and after comparing post test groups a p-value of 0.006 was determined. Regression analysis yeilded an R-square of 0.25. Conclusion: Chocolate has a significant role in augmenting the anti-platelet effects of aspirin.

Purpose: The expression of survivin, a member of the inhibitor-of-apoptosis protein family, is elevated in many types of human cancer. High survivin expression has been associated with poor patient prognosis and tumor resistance to chemotherapy and radiotherapy. The purpose of this study was to compare the radiosensitizing effects of five agents that target survivin on their relative ability to downregulate survivin expression. Methods and Materials: The human epidermoid carcinoma cell line A431 was treated with adenoviral-mediated wild-type p53, antisense to survivin, the mitogen-activated protein kinase inhibitor PD98059, the cyclin-dependent kinase inhibitor Purvalanol A, or the histone deacetylase inhibitor trichostatin A. The radiosensitizing effects of these treatments were determined by clonogenic survival curve analysis and their abilities to suppress survivin expression by Western blot analysis. Results: All the strategies were shown to radiosensitize A431 cells. This effect correlated with their abilities to downregulate survivin. Conclusion: Expression of survivin appears to confer a radioresistant phenotype that can be overcome using several clinically achievable strategies that target survivin either specifically or nonspecifically. © 2006 Elsevier Inc.

The oral availability of many drugs metabolised by the enzyme cytochrome P(450) 3A4 (CYP3A4) is increased if co-administered with grapefruit juice. Extracts from grapefruit peel have also demonstrated inhibitory activity and, during commercial manufacturing of grapefruit juice, inhibitory components might be squeezed into the juice from the peel. Thus, the aim of this in vitro study was to identify CYP3A4 inhibitors in grapefruit peel. Grapefruit peel was extracted with diethyl ether, and the extract was further fractionated by normal-phase chromatography. Fractions demonstrating significant CYP3A4 inhibitory activity, as measured by the relative reduction in N-demethylation of diltiazem in transfected human liver epithelial cells, were subsequently separated by preparative thin-layer chromatography. Constituents of the fractions and isolated compounds were identified by nuclear magnetic resonance spectroscopy. Analysis of diltiazem and N-demethyl-diltiazem was performed using high-...

The primary objective of the present study was to assess the qualitative and quantitative changes of wine polyphenols during in vitro digestion process conducted in a gastrointestinal tract model. Wines selected for these experiments were red grape, white grape and chokeberry wines. Following the stages of in vitro digestion-stomach, small and large intestine-qualitative and quantitative changes particularly in phenolic acids were monitored. Decomposition of resveratrol and chlorogenic acid, secretion of caffeic acid and formation of other derivatives characterized with high antioxidant activity were determined. As a second focus of this work the evaluation of interactions between human fecal microflora (Enterobacteriaceae, Lactobacillus, Enterococcus and Bifidobacterium) and polyphenolic compounds and their derivatives secreted during the digestion were performed.

Rhus succedanea is generally traded, distributed and sold in the markets in its crude and raw form. This may have been mixed with adulterants, mismanaged by malpractices and substituted with other closely related drugs having different effect. This study is therefore carried out to authenticate the plant through pharmacogonostic evaluations. The organoleptic studies were carried through sensory organs i.e size, shape, texrure, odour, etc. Histological studies were conducted by preparing hand slides, mounting the specimen in potato tuber; fluorescence characters were determined through UV and phytochemical screening was investigated using various standard and common methods from relevant literature. Morphologically, the Rhus is a perennial small sized deciduous tree, 5-9 m tall with opposite imparipinnately compound leaves and small grayish yellow flowers born on paniculate inflorescence; locally, called as Rakhkal in Pashto and Kakarsingi in Urdu. The organoleptic evaluation showed ...

Objective: To determine the acetylcholinesterase inhibitory (AChEI) and antioxidant activity of the ethyl acetate and methanol extracts of 12 traditional medicinal plants used in the treatment of neurological disorders. Methods: AChEI activity was determined spectrophotometrically using the Ellman's colorimetric method. Antioxidant activity was carried out by determining the ability of the extracts to scavenge 2,2-diphenyl-1-picryl hydrazyl (DPPH) and 2,2´-azinobis-3ethylbenzothiazoline-6-sulfonic acid (ABTS) radicals. The levels of total phenols, flavonoids and flavonols were determined quantitatively using spectrophotometric methods. Results: AChEI was observed to be dose-dependent. Lannea schweinfurthii (Engl.) Engl. and Scadoxus puniceus (L.) Friis & I. Nordal. root extracts showed the lowest IC 50 value of 0.0003 mg/ml for the ethyl acetate extracts while Zanthoxylum davyi (I. Verd.) P.G. Watermann had the lowest IC 50 value of 0.01 mg/ml for the methanol extracts in the AChEI assay. The roots of Piper capense L.f., Lannea schweinfurthii (Engl.) Engl., Ziziphus mucronata Willd., Zanthoxylum davyi (I. Verd.) P.G. Watermann and Crinum bulbispermum (Burm.f.) Milne-Redh. & Schweick. showed noteworthy radical scavenging activity and good AChEI activity. Conclusions: Five plants showed good antioxidant and AChEI activity. These findings support the traditional use of the plants for treating neurological disorders especially where a cholinesterase mechanism and ROS are involved.

Al though the aetiology of inflammatory bowel disease (IBD) remains unknown, the pathogenesis is gradually being unravelled, seeming to be the result of a combination of environmental, genetic, and immunological factors in which an uncontrolled immune response within the intestinal lumen leads to inflammation in genetically predisposed individuals. Multifactorial evidence suggests that a defect of innate immune response to microbial agents is involved in IBD. This editorial outlines the immunopathogenesis of IBD and their current and future therapy. We present IBD as a result of dysregulated mucosal response in the intestinal wall facilitated by defects in epithelial barrier function and the mucosal immune system with excessive production of cytokines growth factors, adhesion molecules, and reactive oxygen metabolites, resulting in tissue injury. Established and evolving therapies are discussed in the second part of this editorial and at the end of this section we review new therapi...

The antiradical and antioxidant activities of four biologically active N,N-diethyloaminoethyl ethers of flavanone oximes (N,N-DEAEFo) were investigated in vitro and compared with these of polyphenolic flavonoid (rutin). Four experimental models were used: iron-and ascorbate driven Fenton systems, y-radiolysis, xanthine/xanthine oxidase system and diphenylpicrylhydrazyl (DPPH) radical scavenging. The results clearly indicate that N,N-DEAEFo are acting as promising antioxidants and radioprotectors comparable to rutin activities: they should prove to be useful under acute oxidative stress conditions for which both properties were required.

Recent brewing trials indicated the occurrence of valuable bitter compounds in the hard resin fraction of hop. Aiming at the discovery of these compounds, hop's ε-resin was separated by means of a sensory guided fractionation approach and the key taste molecules were identified by means of UV/vis, LC-TOF-MS, and 1D/2D-NMR studies as well as synthetic experiments. Besides a series of literature known xanthohumol derivatives, multifidol glucosides, flavon-3-on glycosides, and p-coumaric acid esters, a total of 11 bitter tastants are reported for the first time, namely, 1″,2″-dihydroxanthohumol F, 4'-hydroxytunicatachalcone, isoxantholupon, 1-methoxy-4-prenylphloroglucinol, dihydrocyclohumulohydrochinone, xanthohumols M, N, and P, and isoxanthohumols M, N, and P, respectively. Human sensory analysis revealed low bitter recognition threshold concentrations ranging from 5 (co-multifidol glucopyranoside) to 198 μmol/L (trans-p-coumaric acid ethyl ester) depending on their chemical...

Propolis or bee-glue is a sticky substance collected in the hives by the honeybee (Apis mellifica L., Apidae) from various tree sources. In the northern hemisphere (Europe, North and South America and western Asia), the tree sources are: Populus spp., Betula spp., Ul-423 Acta Pharm. 55 (2005) 423-430

Aging is a complex and inevitable biological process that is associated with numerous chronically debilitating health effects. Development of effective interventions for promoting healthy aging is an active but challenging area of research. Mechanistic studies in various model organisms, noticeably two invertebrates,Caenorhabditis elegansandDrosophila melanogaster, have identified many genes and pathways as well as dietary interventions that modulate lifespan and healthspan. These studies have shed light on some of the mechanisms involved in aging processes and provide valuable guidance for developing efficacious aging interventions. Nutraceuticals made from various plants contain a significant amount of phytochemicals with diverse biological activities. Phytochemicals can modulate many signaling pathways that exert numerous health benefits, such as reducing cancer incidence and inflammation, and promoting healthy aging. In this paper, we outline the current progress in aging interv...

Six polyphenolic acid esters were synthesized and their antioxidative properties were evaluated in three model systems [2,2-diphenyl-1-picrylhydrazyl (DPPH) free radical scavenging assay, 2,2-azobis(2-amidinopropane)dihydrochloride (AAPH)-induced lipid peroxidation system, and the dye-bleaching assay of peroxynitrite radical]. Among these compounds, we found that compounds 4 [3,4-dihydroxy-benzoic acid-(2-phenoxyethyl ester)], and 5 [3,4-dihydroxy-cinnamic acid-(2-phenoxyethyl ester)] provided comparable activity to caffeic acid phenethyl ester (CAPE) in the DPPH model. Compound 3 [2,5-dihydroxy-benzoic acid-(2-phenoxyethyl ester)], was found to be more active than CAPE in the AAPH system, it also displayed about 2-fold greater activity than CAPE in the peroxynitrite radical model. These results suggest that these phenolic acid ester derivatives, with their potent anti-oxidant activities, may have useful applications as antioxidants.

Four new flavonoids, 3-formyl-4,6,4-trihydroxy-2-methoxy-5-methylchalcone (1), 3-formyl-6,4-dihydroxy-2-methoxy-5-methylchalcone 4-O-b b-D-glucopyranoside (2), (2S)-8-formyl-6-methylnaringenin (3), and (2S)-8-formyl-6-methylnaringenin 7-O-b b-D-glucopyranoside (4) were isolated from the buds of Cleistocalyx operculatus (Myrtaceae). The structures of the new metabolites (1-4) were determined on the basic of spectroscopic analyses including 2 dimensional NMR. Compounds 1 and 3 exhibited 1,1-diphenyl-2-picrylhydrazyl radical scavenging activity with IC 50 values of 22.8 and 27.1 m mM, respectively.

UV-B radiation (280-320 nm) is harmful to living organisms and has detrimental effects on plant growth, development and physiology. In this work we examined some mechanisms involved in plant responses to UV-B radiation. Seedlings of quinoa (Chenopodiurn quinoa Willd.) were exposed to variable numbers of UV-B radiation doses, and the effect on cotyledons was studied. We analyzed (1) cotyledons anatomy and chloroplasts ultrastructure; (2) peroxidase activity involved in the lignification processes; and (3) content of photosynthetic pigments, phenolic compounds and carbohydrates. Exposure to two UV-B doses induced an increase in the wall thickness of epidermal cells, which was associated with lignin deposition and higher activity of the peroxidase. The chloroplast ultrastructure showed an appearance typical of plants under shade conditions, likely in response to reduced light penetration into the mesophyll cells due to the screening effect of epidermal lignin deposition. Exposure to UV-B radiation also led to (1) enhancement in the level of phenolics, which may serve a protective function; (2) strong increase in the fructose content, a fact that might be related to higher requirement of erythrose-4P as a substrate for the synthesis of lignin and phenolics; and (3) reduction in the chlorophyll concentration, evidencing alteration in the photosynthetic system. We propose that the observed lignin deposition in epidermal tissues of quinoa is a resistance mechanism against UV-B radiation, which allows growing of this species in Andean highlands.

The CpG island methylator phenotype is characterized by DNA hypermethylation in the promoters of several suppressor genes associated with the inactivation of various pathways involved in tumorigenesis. DNA methylation is catalyzed by specific DNA methyltransferases (DNMTs). Dietary phytochemicals particularly catechol-containing polyphenols were shown to inhibit these enzymes and reactivate epigenetically silenced genes.

Phenolic compounds and antioxidant activities of four mango varieties cultivated in Brazil were analyzed. The profile of flavonol-Oglycosides and xanthone-C-glycosides was characterized in pulps from Haden, Tommy Atkins, Palmer, and Ubá cultivars and in the agro-industrial residues from Ubá variety by LC-ESI-MS analysis. The first three varieties were collected from conventional production, whereas Ubá was obtained from organic production. The total phenolic content of the peels and seed kernel extracts was analyzed utilizing Folin-Ciocalteu's reagent. The aqueous-methanolic extracts of pulp, peel and seed kernels were analyzed for antioxidant activity (AA) by free radical-scavenging and reducing power. A total of 12 flavonoids and xanthones were identified in the pulps, peels and seed kernels, with larger amounts of these compounds being present in the organically grown Ubá variety. The Ubá mango pulp presented higher AA and the peel and seed kernel extracts showed higher AA than did a commercial standard.

Twelve flavonoids (1-12), isolated from Glycyrrhiza glabra roots were evaluated for their pancreatic lipase (PL) inhibitory activity in vitro. The structures of the isolated compounds were elucidated by spectroscopic methods. Amongst all the compounds 7, 8, 10 and 11 showed strong inhibition against PL with IC 50 values of 7.3 M, 35.5 M, 14.9 M and 37.6 M, respectively. Molecular docking studies on the most active compound 7 revealed that it binds with the key amino acid residues of the PL active site. In silico absorption, distribution, metabolism and excretion (ADME) parameters were also computed on the active compounds to determine their preliminary pharmacokinetic properties. Further, investigations were carried out to determine the antiobesity and lipid lowering effects of 7 and 10 in high fat diet (HFD) fed male SD rats. In the rats supplemented with compound 7 the body weight increase was only 23.2 ± 3.6 g as compared to 64.2 ± 0.5 g in the HFD control group while in the rats treated with compound 10 showed 23.2 ± 3.6 g weight gain only. Compound 7 decreased the levels of plasma total cholesterol (TC) to 84.6 ± 1.4 mg/dl and plasma total triglycerides (TG) to 128.8 ± 6.0 mg/dl. Compound 10 also lowered the plasma TC and TG levels considerably. The results indicate the potential of the chalcone scaffold as a source of PL inhibitors for preventing obesity.

Phenolic compounds present in berries selectively inhibit the growth of human gastrointestinal pathogens. Especially cranberry, cloudberry, raspberry, strawberry and bilberry possess clear antimicrobial effects against e.g. salmonella and staphylococcus. Complex phenolic polymers, such as ellagitannins, are strong antibacterial agents present in cloudberry, raspberry and strawberry. Berry phenolics seem to affect the growth of different bacterial species with different mechanisms. Adherence of bacteria to epithelial surfaces is a prerequisite for colonization and infection of many pathogens. Antimicrobial activity of berries may also be related to antiadherence activity of the berries. Utilization of enzymes in berry processing increases the amount of phenolics and antimicrobial activity of the berry products. Antimicrobial berry compounds are likely to have many important applications in the future as natural antimicrobial agents for food industry as well as for medicine.

The effect of the introduction of distilled rosemary leaves into the diet of the Murciano-Granadina goat on the polyphenolic profile of the goats' milk during the physiological stages of gestation and lactation was studied. The inclusion of rosemary leaves into the animal diet modified neither animal productivity (milk yield) nor milk quality. The following components were found in increased concentration (P < 0.05) in the goats' milk after the introduction of rosemary leaves into their diet: flavonoids hesperidin, naringin, and genkwanin; gallic acid; and phenolic diterpenes carnosol and carnosic acid. With regard to the transfer of polyphenols to the plasma of the suckling goat kid, a statistically significant increase (P < 0.05) in rosmarinic acid, carnosic acid, and carnosol concentrations was detected. From this point of view, distillate rosemary leaves can be proposed as an ingredient in ruminant feed because they both alter neither the yield nor the quality of Murciano-Granadina goats' milk and allow for an increased concentration of polyphenolic components in the goats' milk and in the plasma of the suckling goat kid.

Plants which have been traditionally eaten by alpine populations may provide new opportunities of agricultural development for mountain regions. In this context we investigated the chemical composition of Cirsium spinosissimum (Asteraceae), a perennial thistle. Its receptacles were eaten by shepherds in Valais (Switzerland). Extracts of aerial parts were subjected to a comprehensive metabolite profiling, using a dereplication platform, combining HPLC-PDA-MS and offline microprobe NMR analysis. Twenty compounds, including various phenolic glycosides, a monoterpene lactone, a spermine derivative, and fatty acids, could be identified online, or after targeted isolation. The total phenolic content was determined, and the major flavonoids were quantitatively assessed in fresh receptacles by HPLC-PDA analysis. In addition, substances relevant for nutrition, such as b-carotene, fatty acids, ascorbic acid, and minerals, were quantified. The ethanolic extract of the receptacles showed no sign of cytotoxicity when tested in Caco-2 cells.

The barks of Drimys winteri are used in folk medicine as a remedy to treat several diseases, including dolorous processes. Previous pre-clinical experiments carried out in our laboratories revealed that the hydroalcoholic extract of this plant showed anti-allergenic, anti-inflammatory and antinociceptive properties. Such promising results led us to determine the analgesic compounds present in D. winteri. Through conventional chromatographic procedures with fractions of CH 2 Cl 2 and EtOAc obtained from methanolic extract, it was found that polygodial (1), 1-i-(p-methoxycynnamyl) polygodial (2), taxifolin (3) and astilbin (4), are the main components of these fractions. Compounds 1 and 2 exhibited marked antinociceptive action by intraperitoneal and oral routes against acetic acid-induced abdominal constrictions in mice, suggesting that they are responsible, at least partially, for the antinociceptive effects of this plant. In addition, both compounds were notably more potent than aspirin and acetaminophen, two well-known drugs used here as comparison.

The antioxidant activity of a methanolic extract of Bombax ceiba was evaluated using several antioxidant assays, in terms of its: (i) ability to scavenge DPPH (1,1-diphenyl-2-picryl-hydrazyl) and hydroxyl free radicals; (ii) action against lipid peroxidation (in rat liver microsomes and soy bean phosphatidylcholine liposomes), induced by ascorbyl radicals and peroxynitrite; and (iii) effect on myeloperoxidase activity. The cytotoxicity was monitored through the mitochondrial activity in the Vero cell line. The extract showed antioxidant activity in all assays, the EC 50 (µg/ml) for DPPH was 87 and for lipid peroxidation of microsomes and soy bean liposomes induced by ascorbyl radicals were 141 and 105, respectively, and by peroxynitrite were 115 and 77, respectively. The K 0.5 value for myeloperoxidase activity inhibition by the extract was 264 µg/ml. The extract showed very low toxicity toward Vero cells.

A solvent extraction procedure of freeze-dried aliquots followed by the analysis of phenolic compounds by reversed-phase high-performance liquid chromatography (RP-HPLC) with photodiode array detection (DAD) has been developed for the analysis of polyphenolic compounds in fruit juices. This methodology is focussed on the characterization of fruit juices, mainly for quality control purposes. The effects of experimental variables, such as solvent composition and volume and time and temperature on extraction, have been studied. A unique gradient program for the separation of several phenolic classes (hydroquinones, hydroxybenzoic acids, flavan-3-oles, hydroxycinnamic acids, coumarins, flavanones, flavones, dihydrochalcones and flavonols) has been optimized, using standards of 55 commercially available phenolic compounds present in fruits, as well as representative real extracts from fruit juices. All phenolic compounds showed a high repeatability within-day (n = 5) and between days (n = 3) in peak area (RSD < 8%) and excellent stability of their retention times. High precision was also observed in calibration slopes (RSD < 8%). Detection limits ranged between 0.005 and 0.03 g/mL for the different detected polyphenols. Complete recoveries (98-100%) were obtained for the majority of the phenolic structures of all representative phenolic families present in fruits. The method was successfully employed to measure diverse phenolic families in juices from 18 different fruits and consequently could be used for evaluate the quality of fruit juices.

The aim of our research work was to quantify total flavonoid contents in the leaves of 13 plant species family Asteraceae, 8 representatives of family Lamiaceae and 9 plant species belonging to family Rosaceae, using the multiplex fluorimetric sensor. Fluorescence was measured using optical fluorescence apparatus Multiplex(R) 3 (Force-A, France) for non-destructive flavonoids estimation. The content of total flavonoids was estimated by FLAV index (expressed in relative units), that is deduced from flavonoids UV absorbing properties. Among observed plant species, the highest amount of total flavonoids has been found in leaves of Helianthus multiflorus (1.65 RU) and Echinops ritro (1.27 RU), Rudbeckia fulgida (1.13 RU) belonging to the family Asteraceae. Lowest flavonoid content has been observed in the leaves of marigold (Calendula officinalis) (0.14 RU) also belonging to family Asteraceae. The highest content of flavonoids among experimental plants of family Rosaceae has been estima...

Glucose-6-phosphate dehydrogenase (G6PD)deficient subjects are vulnerable to chemical-induced hemolysis if exposed to oxidative agents. Recent studies reported that green tea and its constituents might act as pro-oxidants. Our objective was to investigate effects of tea and its polyphenolic components on the oxidative status of human G6PD-deficient erythrocytes. Erythrocytes of G6PD-deficient (n=8) and normal (n=8) subjects were incubated with water extracts of 3 types of tea samples (black tea, green tea and decaffeinated green tea extract) and 6 polyphenols. The resulting levels of reduced glutathione (GSH) and glutathione disulphide (GSSG), methemoglobin and plasma hemoglobin were quantified by HPLC and biochemical assays. The tea extracts significantly reduced GSH and increased GSSG levels in G6PD-deficient erythrocytes in a dose-dependent manner (0.5-10 mg/ml), but not in normal erythrocytes. Similar dose-dependent responses to (-)-epigallocatechin (EGC) and (-)-epigallocatechin-3-gallate (EGCG), but not to the other polyphenols, were observed. In G6PD-deficient cells, GSH was reduced by 43.3% (EGC at 0.05 mg/ml) and 33.3% (EGCG at 0.5 mg/ml), compared with pre-challenged levels. The concentration of methemoglobin was increased significantly when challenged with tea extracts, and EGC. Plasma hemoglobin levels were higher in G6PDdeficient samples after exposure to tea extracts, EGCG, EGC and gallic acid, compared with those in normal blood. Tea extracts and polyphenols significantly altered the oxidative status of G6PD-deficient erythrocytes in vitro as demonstrated by the decrease of GSH, and increased GSSG, methemoglobin and plasma hemoglobin. Our data caution against the excessive consumption of concentrated tea polyphenolic products by G6PD-deficient subjects.

Pomegranate peel is a nutritive-rich byproduct whose amounts are extensively growing due to the exponential increase in the production of pomegranate juice and "ready to eat" arils. Pomegranate peel is a rich source for antioxidants and thus may serve in the prevention of cattle diseases and in the improvement of beef products, making it an attractive component in beef cattle diets. The present study aims to evaluate the effect of commonly used storage practices on the nutritive and antioxidative properties of pomegranate peel. In general, storage conditions preserved most antioxidant capacity. Ensiling ambivalently affected the nutritive values of the peel and promoted increased levels of antioxidative components. In addition to polyphenols, nonphenolic components, such as R-and γ-tocopherols, contributed to the total antioxidative capacity, and several minerals found in the peel added to its nutritional value. Dietary supplementation with fresh peels promoted significant increases in feed intake and R-tocopherol concentration in the plasma, with positive tendency toward increased weight gain of bull calves. All in all, the nutritive value and the antioxidant capacity of pomegranate peel turn it into a favorable health-promoting constituent of feedlot beef cattle diet.

The molecular components of a phenolic fraction (P2), obtained from liquid chromatography of a Swiss Chard (Beta vulgaris subsp. cycla) extract, were identified using HPLC-ESI-MS/MS. The primary P2 components were: vitexin-2 00 O-rhamnoside, its demethylated form 2 00 -xylosylvitexin, isorhamnetin 3-gentiobioside, and rutin. P2 ''in toto'' and the single components were characterized for antioxidant capacity, antimitotic activity on MCF-7 human breast cancer cells and for toxicity to human lymphocytes and macrophages. P2 inhibited MCF-7 cell proliferation (IC 50 value ¼ 9 mg/ml) without inducing apoptosis, showed no toxicity to human lymphocytes and slight toxicity to macrophages. Vitexin-2 00 O-rhamnoside strongly inhibited DNA synthesis in MCF-7 cells, whereas 2 00 -xylosylvitexin and isorhamnetin 3-gentiobioside were activators; combinations of activators and inhibitors maintained the over-all inhibitory effect.