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A new pterocarpan glycoside, glycinol-3- O- β- d -glucopyranoside ( 1 ), and a new dihydrochalcone glycoside, ismaeloside A ( 2 ), were isolated together with 13 known compounds, including several flavonoids ( 3 – 8 ), lignan s ( 9 – 11 ), and phenolic compounds ( 12 – 15 ), from the methanol extract of the aerial parts of Ducrosia ismaelis . The chemical structures of these compounds were elucidated from spectroscopic data and by comparison of these data with previously published results. The anti-osteoporotic and antioxidant activities of the isolated compounds were assessed using tartrate-resistant acid phosphatase (TRAP), oxygen radical absorbance capacity (ORAC), and reducing capacity assays. Compound 15 exhibited a dose-dependent inhibition of osteoclastic TRAP activity with a TRAP value of 86.05 ± 6.55% of the control at a concentration of 10 μM. Compounds 1 , 3 – 5 , and 8 showed potent peroxyl radical-scavenging capacities with ORAC values of 22.79 ± 0.90, 25.57 ± 0.49, 20.41 ± 0.63, 26.55 ± 0.42, and 24.83 ± 0.12 μM Trolox equivalents (TE) at 10 μM, respectively. Only compound 9 was able to significantly reduce Cu(I) with 23.44 μM TE at a concentration of 10 μM. All of the aforementioned compounds were isolated for the first time from a Ducrosia species.

Background In metabolite profiling screens or analyses, where generic separation and analysis conditions are used in efforts to measure as many metabolites as possible, overlapping signals from very similar molecules often make it very difficult if not impossible to separate and identify specific molecules of specific classes. The aim of this study was to evaluate the utility of coupling ion mobility spectrometry to UPLC-TOFMS (UPLC-Q-IMS-TOFMS) as a means to separate and identify saturated and unsaturated phenylpropanoic acids and chalcones, phenylpropanoid-acetate pathway derived compounds that are common in plant extracts. Results This approach readily separated most of the unsaturated phenylpropanoid acids (t-cinnamate, p-coumarate, caffeate, ferulate) from the corresponding saturated (dihydro-) compounds, and analysis of two dimensional plots of mass/charge ratio values versus ion mobility drift time revealed that the other compounds can indeed be distinguished. However, this approach was less effective for the larger chalcones. Conclusions UPLC-Q-IMS-TOFMS is a promising tool to enable the separation, identification and quantification of very similar molecules. Although it has its limitations, as was seen for the chalcones that were not well separated in this investigation, ion mobility spectrometry nevertheless adds an additional level of characterization to large-scale metabolomic screens, which increases the power of such screens without the demand for multiple analyses using very different column chemistries.

The apple tree ( Malus sp.) is an agriculturally and economically important source of food and beverages. Many of the health beneficial properties of apples are due to (poly)phenolic metabolites that they contain, including various dihydrochalcones. Although many of the genes and enzymes involved in polyphenol biosynthesis are known in many plant species, the specific reactions that lead to the biosynthesis of the dihydrochalcone precursor, p -dihydrocoumaroyl-CoA ( 3 ), are unknown. To identify genes involved in the synthesis of these metabolites, existing genome databases of the Rosaceae were screened for apple genes with significant sequence similarity to Arabidopsis alkenal double bond reductases. Herein described are the isolation and characterization of a Malus hydroxycinnamoyl-CoA double bond reductase, which catalyzed the NADPH-dependent reduction of p -coumaroyl-CoA and feruloyl-CoA to p -dihydrocoumaroyl-CoA and dihydroferuloyl-CoA, respectively. Its apparent K m values for p -coumaroyl-CoA, feruloyl-CoA and NADPH were 96.6, 92.9 and 101.3 μM, respectively. The Malus double bond reductase preferred feruloyl-CoA to p -coumaroyl-CoA as a substrate by a factor of 2.1 when comparing catalytic efficiencies in vitro . Expression analysis of the hydroxycinnamoyl-CoA double bond reductase gene revealed that its transcript levels showed significant variation in tissues of different developmental stages, but was expressed when expected for involvement in dihydrochalcone formation. Thus, the hydroxycinnamoyl-CoA double bond reductase appears to be responsible for the reduction of the α , β -unsaturated double bond of p -coumaroyl-CoA, the first step of dihydrochalcone biosynthesis in apple tissues, and may be involved in the production of these compounds.

Background Apples are an important source of polyphenols in the human diet and the consumption of this fruit has been linked to the prevention of degenerative diseases. Results Catechins, procyanidins, hydroxycinnamic acids, flavonol glycosides, dihydrochalcone glycosides and one anthocyanin: cyanidin-3-O-galactoside, were identified both in the peel and pulp. Procyanidins, catechins and flavonols represent the main constituents of peel. Concerning the antioxidant activity, in the reduction of the stable DPPH radical and in the inhibition of lipid peroxidation, the ethanolic extracts of red peel and red pulp showed a good similar activity comparable to ascorbic acid in the DPPH test and about ten times more active than BHT in the lipoxygenase test, and were much more active than aqueous extracts. The ORAC value of red pulp aqueous extract resulted comparable to that of red berries: vaccinium, rubus and ribes, foods appreciated for their health value. Conclusion This apple contains an appreciable amount of polyphenols also in the flesh; this variety with red flesh can also be useful for researchers engaged in apples varietal innovation in addition to being used as food apple.

Three flavanones, two chalcones and one dihydrochalcone were isolated from the branches of Piper glandulosissimum. All isolated compounds were characterized based on IR, UV, 1H and 13C NMR, including 2D NMR analyses (HMQC, HMBC, COSY and NOESY) and comparison with the literature. The compound 7-hydroxy-5,8-dimethoxyflavanone displayed antimicrobial activity against Staphylococcus aureus, S. epidermidis, Trichophyton mentagrophytes and Microsporum canis.

Dihydrochalcone derivative, 3',5'-di-C-beta-glucopyranosylphloretin (1), is present in the genus Fortunella, (F. crassifolia, F. japonica, F. margarita, F. polyandra and F. hindsii). These species accumulate a large quantity of 1 in their fruits (peel, 6.5-15.2 mg/g in dry wt; juice sac, 1.5-10.5 mg/g) and in their leaves (21.3-60.2 mg/g). Twenty-seven Tanaka's Citrus species examined lack 1, but C. madurensis and C. halimii contain 1 in large quantities in their peels (25.1 and 33.6 mg/g) and juice sacs (4.1 and 4.2 mg/g). Poncirus species do not contain 1. Fortunella-citrus hybrids, the Orangequat [C. unshiuxF. crassifolia], the Thomasville citrangequat [Fortunella sp.x(C. sinensisxPoncirus trifoliata)], and seven hybrid progenies [F. margaritaxC. junos], contain large amounts of 1 in their peels (17.0-7.9 mg/g) and juice sacs (2.0-9.9 mg/g). These facts suggest that accumulation of 1 is a generic trait of the genus Fortunella and that the inheritance of the trait among the intergeneric hybrids is controlled by a dominant allele. Thus C. madurensis and C. halimii are thought to originate from natural hybrids between the genera Citrus and Fortunella. Phloridzin, which has the same aglycon as 1, was not detected in the citrus plants examined.

A new dihydrochalcone, two new dihydroflavanones and eight new biflavonoids have been isolated together with cryptocaryone from the cytotoxic methanol extract of Cryptocarya infectoria. The absolute structure of cryptocaryone was established by X-ray analysis of its 8-bromo derivative. The structure of the new compounds were elucidated by spectroscopic means and their absolute stereochemistry was deduced from chemical correlation, circular dichroism data and NOESY experiments. Several compounds displayed significant cytotoxicity and cryptocaryone was shown to possess cytotoxicity towards multi-drug resistant K562-DOX cells.

Aldose reductase, the key enzyme of the polyol pathway, and oxidative stress are known to play important roles in the complications of diabetes. A drug with potent inhibition of aldose reductase and oxidative stress, therefore, would be a most promising drug for the prevention of diabetic complications. The purpose of this study was to develop new compounds with these dual-effects through synthesis of chalcone derivatives and by examining the structure-activity relationships on the inhibition of rat lens aldose reductase as well as on antioxidant effects. A series of 35 flavonoid derivatives were synthesized by Winget's condensation, oxidation, and reduction of appropriate acetophenones with appropriate benzaldehydes. The inhibitory activity of these derivatives on rat lens aldose reductase and their antioxidant effects, measured using Cu2+ chelation and radical scavenging activities on 1,1-diphenyl-picrylhydrazyl in-vitro, were evaluated. Their effect on sorbitol accumulation in the red blood cells, lenses and sciatic nerves of streptozotocin-induced diabetic rats was also estimated. Among the new flavonoid derivatives synthesized, those with the 2′,4′-dihydroxyl groups in the A ring such as 2,4,2′,4′-tetrahydroxychalcone (22), 2,2′,4′-trihydroxychalcone (11), 2′,4′-dihydroxy-2,4-dimethylchalcone (21) and 3,4,2′,4′-tetrahydroxychalcone (18) were found to possess the highest rat lens aldose reductase inhibitory activity in-vitro, their IC50 values (concentration of inhibitors giving 50% inhibition of enzyme activity) being 1.6 times 10−7, 3.8 times 10−7, 4.0 times 10−7 and 4.6 times 10−7 M, respectively. All of the chalcones tested except 3, 18, 23 with o-dihydroxy or hydroquinone moiety showed a weak free radical scavenging activity. In the in-vivo experiments, however, compound 18 with o-dihydroxy moiety in the B ring showed the strongest inhibitory activity in the accumulation of sorbitol in the tissues. It also showed the strongest activity in transition metal chelation and free radical scavenging activity. Of the 35 4,2′-dihydroxyl and 2′,4′-dihydroxyl derivatives of flavonoid synthesized, including chalcone, flavone, flavanone, flavonol and dihydrochalcone, some chalcone derivatives synthesized were found to possess aldose reductase inhibition and antioxidant activities in-vitro as well as inhibition in the accumulation of sorbitol in the tissues in-vivo. 3,4,2′,4′-Tetrahydroxychalcone (18, butein) was the most promising compound for the prevention or treatment of diabetic complications.

The total synthesis of angoluvarin, a member of the dihydrochalcone family of natural products, is reported. Starting with 2-bromophenol, the synthesis was accomplished in eight steps with an overall yield of 2%. This represents the first reported synthesis of angoluvarin.

A new benzoquinone-type retro-dihydrochalcone, named evelynin, was isolated from the roots and rhizomes of Tacca chantrieri. The structure was elucidated based on the analysis of spectroscopic data and confirmed by a simple one-step total synthesis. Evelynin exhibited cytotoxicity against the 4 human cancer cell lines, including MDA-MB-435 melanoma, MDA-MB-231 breast, PC-3 prostate, and HeLa cervical carcinoma cells with IC50 values of 4.1, 3.9, 4.7, and 6.3 μM, respectively.

Apple juices were produced by way of a two-stage process consisting of traditional enzyme treatment of the mash with pectinases for the premium juices and pomace liquefaction with different pectinases and cellulases for the extraction juices. Premium and extraction juices were analysed separately. Calculated to an equal juice strength of 12° Brix, there was an increase of D-galacturonic acid and cellubiose in the extraction juices. Released galacturonic acid from cell wall material was found at levels ranging from 107 mg/l to 1239 mg/l. This was an essential contribution to the total titrable acid of the extraction juices. The sum of phenolic substances determined by high performance liquid chromatography was significantly higher in all the extraction juices than in the corresponding premium juices. Among the phenolics, the dihydrochalcone phloretin 2′-glucoside (92–110 mg/l) showed an increase of 4 to 5 times the concentration in the respective premium juices. Quercetin derivatives were mainly present in the extraction juices; here the values were between 32 mg/l and 38 mg/l. Under the influence of strong pectolytic or cellulolytic enzyme activities, oligo- and polysaccharides are released from the apple cell wall material, resulting in colloid concentrations of up to 15 g/l in the extraction juices. High concentrations of polyphenols and pectic polysaccharides can lead to technological problems. However, pomace liquefaction may also turn out to be suitable for obtaining value-added foods. In respect to nutritional aspects, enzymatic treatment of pomace offers the opportunity of releasing apple polyphenols and polysaccharides contained in the pomace to a greater extent and obtaining them preparatively.

A new dihydrochalcone, 6''-acetylphloridzosid, was isolated from the whole plant of Loiseleuria procumbens (L.) Desv. and identified as 2'-O-(6''-O-acetylglucopyranosyl)-4,4',6'-trihydroxydihydrochal cone by spectroscopic methods. In addition, one stilbene and three other dihydrochalcones were identified as (E)-piceid, phloretin (2',4,4',6'-tetrahydroxydihydrochalcone), phloridzosid (2'-O-glucopyranosyl-4,4',6'-trihydroxydihydrochalcone) and asebotin (2'-O-glucopyranosyl-4'-methoxy-4,6'-dihydroxydihydrochalcone), respectively. Some of these compounds showed scavenging properties towards the 2,2-diphenyl-1-picrylhydrazyl radical and antioxidant properties in a test with lysozyme.

The purpose of this study was to determine the degree to which the sodium salt of +/-2-(4-methoxyphenoxy)propanoic acid (Na-PMP) reduced sweet intensity ratings of 15 sweeteners in mixtures. Na-PMP has been approved for use in confectionary/frostings, soft candy and snack products in the USA at concentrations up to 150 p.p.m. A trained panel evaluated the effect of Na-PMP on the intensity of the following 15 sweeteners: three sugars (fructose, glucose, sucrose), three terpenoid glycosides (monoammonium glycyrrhizinate, rebaudioside-A, stevioside), two dipeptide derivatives (alitame, aspartame), two N-sulfonylamides (acesulfame-K, sodium saccharin), two polyhydric alcohols (mannitol, sorbitol), 1 dihydrochalcone (neohesperidin dihydrochalcone), one protein (thaumatin) and one sulfamate (sodium cyclamate). Sweeteners were tested at concentrations isosweet with 2.5, 5, 7.5 and 10% sucrose in mixtures with two levels of Na-PMP: 250 and 500 p.p.m. In addition, the 15 sweeteners were tested either immediately or 30 s after a pre-rinse with 500 p.p.m. Na-PMP. In mixtures, Na-PMP at both the 250 and 500 p.p.m. levels significantly blocked sweetness intensity for 12 of the 15 sweeteners. However, when Na-PMP was mixed with three of the 15 sweeteners (monoammonium glycyrrhizinate, neohesperidin dihydrochalcone and thaumatin), there was little reduction in sweetness intensity. Pre-rinsing with Na-PMP both inhibited and enhanced sweetness with the greatest enhancements found for monoammonium glycyrrhizinate, neohesperidin dihydrochalcone and thaumatin, which were not suppressed by Na-PMP in mixtures. The mixture data suggest that Na-PMP is a selective competitive inhibitor of sweet taste. The finding that pre-treatment can produce enhancement may be due to sensitization of sweetener receptors by Na-PMP.

(3R)-O-beta-D-Glucopyranosyloxy-5-phenylvaleric acid (1), (3R)-O-beta-D-glucopyranosyloxy-5-phenylvaleric acid n-butyl ester (2), and a new dihydrochalcone diglycoside 4'-O-[beta-D-glucopyranosyl-(1--6)-glucopyranosyl]oxy-2'-hydroxy-3', 6'-dimethoxydihydrochalcone (3), together with six known flavonoid glycosides [kaempferol-3-O-beta-D-glucopyranoside (= astragalin) (4), kaempferol-3-O-beta-D-galactopyranoside (5), quercetin-3-O-beta-D-glucopyranoside (= isoquercitrin) (6), quercetin-3-O-beta-D-galactopyranoside (= hyperoside) (7), quercetin-3-O-(2''-O-galloyl)-beta-D-glucopyranoside (8), and quercetin-3-O-beta-D-glucuronopyranoside (9)] were isolated from the aerial parts of Polygonum salicifolium. The structure elucidation of the isolated compounds was performed by spectroscopic (UV, IR, ESI-MS, 1D- and 2D-NMR), chemical (methylation, enzymatic hydrolysis, partial synthesis), and chromatographic methods (HPLC, Chiralcel OD). The flavonoid glycosides (4-9) demonstrated scavenging properties toward the 2,2-diphenyl-1-picrylhydrazyl (DPPH) radical in TLC autographic assays.

A new dihydrochalcone, 4'-hydroxy-4,2'-dimethoxy-dihydrochalcone, was isolated from Chinese dragon's blood, the red resin of Dracaena cochinchinensis. Its structure was established by spectrum analysis.

AIM: To study the chemical constituents of Longdan Xiegan Decoction, one of the most famous Traditional Chinese Medicine prescriptions. METHODS: Silica gel, C18 reversed phase silica gel, Sephadex LH-20 column chromatography were used. The structures of isolated compounds were elucidated by various physiochemical properties and spectral data. RESULTS: Five com-pounds were obtained and identified as 2',4' -dihydroxydihydrochalcone-3'-C-β-glucopyranosyl-6'-O-β-D-glucopyranoside (1), isoliquiritigenin (2), echinatin (3), licochalcone B (4), and isoliquiritin (5). CONCLUSION: Compound 1 is new and compounds 2-5 were isolated from Longdan Xiegan Decoction for the first time.

Bioguided fractionation of the extracts from leaves of Piper mollicomum and Piper lhotzkyanum against the fungi Cladosporium cladosporioides and C. sphaerospermum afforded seven bioactive compounds, four being chromenes: methyl 2,2-dimethyl-2H-chromene-6-carboxylate, methyl 8-hydroxy-2,2-dimethyl-2H-chromene-6-carboxylate, 2-methyl-2-[4'-methyl-3'-pentenyl]-2H-1-benzopyran-6-carboxylic acid, 2,2-dimethyl-2H-chromene-6-carboxylic acid, one a dihydrochalcone: 2',6'-dihydroxy-4'-methoxydihydrochalcone, and two flavanones: 7-methoxy-5,4'-dihydroxy-flavanone and 7,4'-dimethoxy-5-hydroxy-flavanone. The structures of the bioactive isolated derivatives were elucidated by interpretation of their NMR data [¹H and 13C (BBD, DEPT 135º)], and mass spectral data as well as by comparison with data described in the literature.

Two new flavones with a hydroxymethyl substitution in the B-ring, 8,10-dihydroxy-5- H -isochromeno[4,3- b ]chromen-7-one and 8,10-dihydroxy-11-methoxy-5- H -isochromeno[4,3- b ]chromen-7-one and ten B-ring non-substituted dihydrochalcones, chalcones, flavonols including two new flavanonol stereoisomers, cis -3-acetoxy-5,7-dihydroxyflavanone and cis -3-hydroxy-5,7-dimethoxyflavanone, have been isolated from the dichloromethane extract of fronds of the North American fern Woodsia scopulina . Furthermore, two humulanetype sesquiterpenes, humulene-6,7-epoxide and the new compound 6,7-epoxy-5-hydroxyhumula-2,9-diene, were obtained from this plant. Their structures have been identified by spectroscopic analysis.

A new dihydrochalcone, 3′,5′-dihydroxy-2′,4′,6′-trimethoxydihydrochalcone and five known compounds, methyl linderone, 5-hydroxy-6,7,8-trimethoxyflavone (alnetin), 2′-hydroxy-3′,4′,5′,6′-tetramethoxydihydrochalcone (dihydrokanakugiol), 2′-hydroxy-3′,4′,5′,6′-tetramethoxychalcone (kanakugiol) and 2′,3′,4′,5′,6′-pentamethoxychalcone (pedicellin) were isolated from twigs of Lindera lucida. The structures of these compounds were determined by spectral analyses and chemical correlations.

Flavonoids as naturally occurring compounds of plant derived foodstuff reveal some biological effects (antioxidative, antimutagenic, anticarcinogenic) which makes them interesting substances in the prevention of atherosclerosis and cancer in humans. Data on the flavonoid content of food are not considered in food composition tables, and human intake data are scarce (flavonols) or missing. Consequently, after installing a flavonoid data base by means of literature data, 7-d dietary protocols of 119 adults (63 women and 56 men, age 19-49 years) representing a bavarian subgroup of the German National Food Consumption Survey (NVS) were evaluated. In all subjects, average intake of all flavonoids (calculated as aglycons) amounts to 54.0 mg/d (median) with a great range of variability. The most important flavonoid groups are flavonols (12.0 mg/d), catechins (8.3 mg/d), and flavanons (13.2 mg/d), followed by anthocyanidins (2.7 mg/d), proanthocyanins (3.7 mg/d) and phloretin (dihydrochalcone) (0.7 mg/d). Sex differences did not reach statistical significance. Fruits, fruit products and fruit juices were the most important flavonoid sources. Vegetables and its products provided about half of the flavonol intake. Therefore, statistically significant correlations (p < 0.001) exist between total flavonoid intake and the intake of vitamin C (r = 0.59) or dietary fiber (r = 0.49). Compared to other countries, flavonol intake of the investigated group of persons is rather low. With the built data base it was possible for the first time to calculate the intake of further flavonoids besides flavonols. In comparison to the intake of other antioxidants (e.g. vitamins C and E) the amount of flavonoids in the diet is considerably high and therefore should be regarded in further investigations on the role of diet in certain diseases.

Purées and concentrates are intermediate products in the elaboration of commercial fruit juices. In this paper, the phenolic composition was established and quantified in a large number of samples of peach and apple purées and concentrates. Different benzoic acids and aldehydes, cinnamic acids and their derivatives, flavan-3-ols, procyanidins, flavonols, and dihydrochalcones have been identified. The concentration of cinnamic acids and derivatives is higher in the concentrates than in the purées for both fruits. However, flavan-3-ols and procyanidins are only present in the purées. Peach-based products are completely devoid of flavonol and dihydrochalcone derivatives due to the removal of the skin of the fruit in the manufacturing process. On the other hand, different quercetin and phoretin glycosides were detected in apple purées and concentrates. The results show that phenolic compounds can prove to be helpful in the characterization of fruit purées and concentrates as well as in the detection of adulterations in the manufacturing of commercial fruit juices from these intermediates.

From the EtOH extract of the stem bark of Mitrella kentii (Annonaceae), two new terpenylated dihydrochalcones were isolated, namely (−)-neolinderatin (1) and (−)-linderatin (2), together with known compounds 2‘,6‘-dihydroxy-4‘-methoxydihydrochalcone and (+)-catechin. Their structures were elucidated by means of combined analytical methods including HREIMS, DC, 1D, and 2D NMR spectroscopies.

Three new and unusual biflavonoids, composed of a flavonol and dihydrochalcone nucleus through a methylene group, were isolated from the farinose exudate of Pentagramma triangularis in addition to a herbacetin dimethyl ester. These structures were determined by means of spectroscopic analysis.

Six aromatic compounds, asebogenin (1), 2',6'-dihydroxy-4'-methoxydihydrochalcone (2), 3-geranyl-4-methoxy-benzoic acid (3), 3-geranyl-4-hydroxybenzoic acid (4), nervogenic acid (5) and 2,2-dimethyl-6-carboxyl-8-prenyl-chromene (6) were isolated from the methanol extract of the aerial part of Piper elongatum VAHL., whose leaves are used as a folk medicine in South America. The structures of 1-6 were elucidated by MS, 1H-NMR and 13C-NMR spectroscopies, and chemical evidence. Among these compounds, 1 showed stronger antioxidative activity than that of α-tocopherol, and 4 and 5 exhibited higher activity than that of t-butyl-4-hydroxyanisole (BHA) using the ferric thiocyanate method.

Flemingia philippinensis is used as a foodstuff or medicinal plant in the tropical regions of China. The methanol (95%) extract of the roots of this plant showed potent tyrosinase inhibition (80% inhibition at 30μg/ml). Activity-guided isolation yielded six polyphenols that inhibited both the monophenolase (IC50=1.01-18.4μM) and diphenolase (IC50=5.22-84.1μM) actions of tyrosinase. Compounds 1-6 emerged to be three new polyphenols and three known flavanones, flemichin D, lupinifolin and khonklonginol H. The new compounds (1-3) were identified as dihydrochalcones which we named fleminchalcones (A-C), respectively. The most potent inhibitor, dihydrochalcone (3) showed significant inhibitions against both the monophenolase (IC50=1.28μM) and diphenolase (IC50=5.22μM) activities of tyrosinase. Flavanone (4) possessing a resorcinol group also inhibited monophenolase (IC50=1.79μM) and diphenolase (IC50=7.48μM) significantly. In kinetic studies, all isolated compounds behaved as competitive inhibitors. Fleminchalcone A was found to have simple reversible slow-binding inhibition against monophenolase.

A rapid, sensitive and selective UPLC/MS method using LTQ Orbitrap mass spectrometry was established for the analysis and characterization of the main biological components and their metabolites in rat plasma, urine and feces following oral administration of Lithocarpus polystachyus extract. In vivo, 22 flavonoid metabolites were observed in rat plasma, and 13 metabolites were detected in rat urine, whereas just two aglycones of dihydrochalcone (3-hydroxy phloretin and phloretin) could be detected in rat feces. Among these metabolites, one new and a known dihydrochalcone metabolite were isolated and definitely identified. Besides, five dihydrochalcone metabolites were tentatively identified as new compounds. A metabolism study of 3-hydroxyphlorizin and phloridzin was also conducted. Glucuronidation was the main metabolic pathway of phloridzin, whereas glucuronidation and sulfonation were the main metabolic pathway of 3-hydroxyphlorizin. These results provided a basis for evaluating the bioactive components of a complex natural medicine and their mechanisms of actions.

Together with the sweet principle component glycyphyllin A (3), seven phenolic compounds including two new dihydrochalcone rhamnopyranosides, glycyphyllin B (1) and glycyphyllin C (2), and five known flavonoids, catechin (4), kaempferol-3-O-β-D-glucopyranoside (5), quercetin-3-O-β-D-glucopyranoside (6), kaempferol-3-O-β-neohesperidoside (7), and 2R,3R-dihydrokaempferol-3-O-β-D-glucopyranoside (8), have been isolated from the ethanolic extract of the leaves of Smilax glyciphylla for the first time. The structures of these compounds were characterized by spectroscopic methods including UV, MS, and 1D and 2D NMR. In vitro antioxidant capacity tests employing FRAP and DPPH assays indicated that 1, 4, and 6 exhibited potent antioxidant activity and are the key phenolics responsible for the antioxidant activity of the leaf extract of S. glyciphylla.

The bulbs of Ledebouria socialis (Hyacinthaceae) yielded the benzocyclobutene homoisoflavonoid, (R)-2',5-dihydroxy-3',4',7-trimethoxyspiro{2H-1-benzopyran-3-(4H)-9-bicyclo[4.2.0]octa[1,3,5]triene}-4-one, socialinone (1). Ledebouria ovatifolia yielded (2e,3R)-2,5-dihydroxy-7-methoxyspiro[2H-1-benzopyran-3(4H), 5'(6'H)-cyclobuta[f][1,3]benzodioxol]-4-one (2) and the homoisoflavanone, (E)-3-(3',4'-dihydroxybenzylidene)-5,7-dihydroxychroman-4-one, ovatifolionone (5), the dihydrochalcone, 4,4'-dihydroxy-2',6'-dimethoxydihydrochalcone (3), and xanthone, 1,6-dihydroxy-2,3,5-trimethoxy-8-methyl-9H-xanthen-9-one (4) along with 21 known compounds. Structures were determined using spectroscopic techniques. The anti-inflammatory activities of the homoisoflavonoids and xanthones isolated were evaluated against cyclooxygenase-1 and -2 isoenzymes. (R)-3-(3',4'-Dihydroxybenzyl)-7-hydroxy-5-methoxychroman-4-one (7), (E)-3-(3',4'-dihydroxybenzylidene)-7-hydroxy-5-methoxychroman-4-one (10), 1,3,6-trihydroxy-2-methoxy-8-methylxanthen-9-one (6) and ovatifolionone acetate (5Ac) exhibited significant activity against cyclooxygenase-2 at

In relation to their antioxidant potential, phenolic compounds are usually associated with a protective effect on the human health of a diet rich in fruits and vegetables. They are also widely associated to the organoleptic quality of ciders since they affect bitterness, astringency, color and aroma. Two studies have recently been published on QTL detection for the phenolic content of dessert apple. No study has yet been published for cider apple, even though they are usually more concentrated in phenolic compounds The objective of this work was to identify genomic regions involved in the phenolic content for a cider apple progeny. In a first time, two quantification methods were developed and compared in UHPLC-UV and UHPLC-MS/MS for major phenolic compounds in juices. Even overestimation of some compounds with one detector were observed, these two methods were highly correlated. Phenolic compounds of whole fruits were also quantified at the INRA station of Rennes. A high variability was observed in both fruits and juices of this progeny, representative of major cider apple varieties grown in Europe. 48 QTL were detected on nine linkage groups (LG). Nine clusters seem particularly stable according to the year or material study. Enzymes of the polyphenol pathway and transcription factors were targeted as candidate gene and identified in silico under major QTL. This work offers new targets for the marker-assisted selection like the QTL for chlorogenic acid on LG17 to improve cider apple varieties.; En lien avec leur potentiel antioxydant, les composés phénoliques sont généralement associés à l'effet protecteur sur la santé d'une alimentation riche en fruits et légumes. Ils sont également fortement associés à la qualité organoleptique des cidres puisqu'ils affectent directement leur astringence, leur amertume, leur couleur et leurs arômes. Deux études ont récemment été publiées sur la détection de QTL des composés phénoliques des pommes de table. Aucune étude n'a encore été publiée pour les pommes à cidre, réputées pour leur forte teneur en composés phénoliques. L'objectif de cette thèse est d'identifier les régions génétiques impliquées dans la teneur en composés phénoliques d'une descendance de pommiers à cidre. Dans un premier temps, deux méthodes de quantification ont été développées et comparées en UHPLC-UV et UHPLC-MS/MS pour les principaux composés phénoliques du jus de pomme. Bien qu'il y ait des surestimations avec l'un des détecteurs pour certains composés, ces deux méthodes corrèlent très fortement. Des dosages ont également été réalisés sur fruit entier à l'INRA de Rennes. Une grande variabilité a été observée pour les fruits et les jus de cette descendance, représentative des principales variétés de pommes à cidre cultivées en Europe. 48 QTL ont été détectés sur neuf groupes de liaison (LG). Neuf clusters semblent particulièrement stables, indépendamment de l'année ou du matériel (fruit ou jus) étudié. Les enzymes de la biosynthèse des composés phénoliques et facteurs de transcription ont été ciblés pour l'identification des gènes candidats, réalisée au niveau des principaux QTL. Ces travaux proposent de nouvelles cibles pour la sélection assistée par marqueurs comme le QTL pour l'acide chlorogénique du LG17 pour l'amélioration des variétés de pommes à cidre

Sofrito is a key component of the Mediterranean diet, a diet that is strongly associated with a reduced risk of cardiovascular events. In this study, different Mediterranean sofritos were analysed for their content of polyphenols and carotenoids after a suitable work-up extraction procedure using liquid chromatography/electrospray ionisation-linear ion trap quadrupole-Orbitrap-mass spectrometry (LC/ESI-LTQ-Orbitrap-MS) and liquid chromatography/electrospray ionisation tandem triple quadrupole mass spectrometry (LC/ESI-MS-MS). In this way, 40 polyphenols (simple phenolic and hydroxycinnamoylquinic acids, and flavone, flavonol and dihydrochalcone derivatives) were identified with very good mass accuracy (

Adenosine monophosphate (AMP)-activated protein kinase (AMPK) is a major cellular energy sensor and master regulator of metabolic homeostasis; thus, AMPK plays a central role in studies on diabetes and related metabolic diseases. From the rhizomes of Polygonatum odoratum (Mill.) Druce, six homoisoflavonoids (1-6) and one dihydrochalcone (7) were isolated, and the structures of polygonatones A-D (4-7) were elucidated by various spectroscopic analyses. Compounds 1-7 were evaluated for their effect on AMPK activation. The amount of active phosphorylated AMPK and acetyl-CoA carboxylase in rat liver epithelial IAR-20 cells increased when the cells were incubated with the aforementioned compounds. Specifically, (3R)-5,7-dihydroxyl-6-methyl-8-methoxyl-3-(4'-hydroxylbenzyl)-chroman-4-one (1), (3R)-5,7-dihydroxyl-6,8-dimethyl-3-(4'-hydroxylbenzyl)-chroman-4-one (2), (3R)-5,7-dihydroxyl-6-methyl-3-(4'-hydroxylbenzyl)-chroman-4-one (3), and polygonatone D (7) exhibited significant activation effects.

Flavonoids, like other metabolites synthesized via the phenylpropanoid pathway, possess a wide range of biological activities including functions in plant development and its interaction with the environment. Dihydrochalcones (mainly phloridzin, sieboldin, trilobatin, phloretin) represent the major flavonoid subgroup in apple green tissues. Although this class of phenolic compounds is found in very large amounts in some tissues (approximate to 200 mg/g of leaf DW), their physiological significance remains unclear. In the present study, we highlight their tissue-specific localization in young growing shoots suggesting a specific role in important physiological processes, most notably in response to biotic stress. Indeed, dihydrochalcones could constitute a basal defense, in particular phloretin which exhibits a strong broad-range bactericidal and fungicidal activity. Our results also indicate that sieboldin forms complexes with iron with strong affinity, reinforcing its antioxidant properties and conferring to this dihydrochalcone a potential for iron seclusion and/or storage. The importance of localization and biochemical properties of dihydrochalcones are discussed in view of the apple tree defense strategy against both biotic and abiotic stresses. (C) 2013 Elsevier Ltd. All rights reserved.

By the virtual screening method we have screened out Dihydrochalcone as a top-lead for the Alzheimer's disease using the database of about 32364 natural compounds. The binding affinity of this ligand to amyloid beta (Aβ) fibril has been thoroughly studied by computer simulation and experiment. Using the Thioflavin T (ThT) assay we have obtained the inhibition constant IC50 μM. This result is in good agreement with the estimation of the binding free energy obtained by the molecular mechanic-Poisson Boltzmann surface area method and all-atom simulation with the force field CHARMM 27 and water model TIP3P. Cell viability assays indicated that Dihydrochalcone could effectively reduce the cytotoxicity induced by Aβ. Thus, both in silico and in vitro studies show that Dihydrochalcone is a potential drug for the Alzheimers disease.

Leptoderris fasciculata (Benth.) Dunn is a woody liana that grows in the tropical zone of West Africa, where it is exploited in traditional medicine for a number of uses. In the south-eastern Ivory Coast, it is applied to stop bleeding in women after childbirth or in cases of menorrhagia. The phytochemistry of this plant has received little previous attention. We report the isolation of 40,5,6,7-tetramethoxyisoflavone and dihydrochalcone, new as natural products, together with 10 known compounds from the leaves of L. fasciculata collected in the Ivory Coast. (C) 2013 Phytochemical Society of Europe. Published by Elsevier B. V. All rights reserved.

A new dihydrochalcone derivative, lusianin, two other known chalcones and a phenanthrene derivative were isolated from the orchid Lusia volucris. The two chalcones and the phenanthrene derivative were characterized as 2-propene-1-one-1-(2′,4′-dihydroxy-3′-methoxyphenyl)-3-(4″-methoxyphenyl) and 2-propene-1-one-1-(2′-hydroxy-4′-methoxyphenyl)-3-(4″-methoxyphenyl) and 6-hydroxy-2,4,7-trimethoxyphenanthrene(batatasin-I), respectively, by independent spectral analysis of the compounds and their acetyl derivatives. The structure of lusianin was established as 1-propanone-1-(2′,4′-dihydroxy-3′-methoxyphenyl)-3-(4″-methoxyphenyl) from spectral and chemical evidence.

Model solutions containing chlorogenic acid (CG) and (-)-epicatechin (EP), and phenolics from nine apple cv., were oxidized with apple polyphenoloxidase (PPO). Browning was determined by absorbance at 380–700 nm, and transformed into CIE L*, a* and b*. Multilinear correlations were established between initial and degraded amounts of each phenolic. In model solutions of CG and EP, color values and A400 correlated strongly with initial and oxidized CG and EP. Both phenolics contributed to decrease in L* and increase in A400. Increase ii CG increased a*, but EP had little effect. The imnact of increased EP on b* was two to three times higher than for CG: In each phenol class (hydroxycinnamic (HD), flavan-3-ol (FA), flavonol (FO) and dihydrochalcone (DC) derivatives), degraded amounts were increased or decreased by increasing amounts of other classes. Besides major phenolics, HD (mainly CG) and FA (mainly EP and procyanidin B2), FO and DC, appeared to affect color development.

The apple is a food rich in diverse classes of polyphenols (PP), among which the proanthocyanidins (PCs), which are primarily concentrated in the skin, are one of the most abundant. These compounds are of considerable interest for their possible positive health effects because of their antioxidant properties. However, depending on the classes of PP present (chemical composition) and their relative concentrations in the apple skin, their antioxidant effects vary and some of their components can even generate prooxidant effects. This work determined the chemical composition and antioxidant-prooxidant potential of a polyphenolic extract (PPE) and a proanthocyanidin-rich fraction (PRF) of apple skin, along with the contribution of their most abundant individual compounds, based on their copper chelating ability, ease in reducing peroxidase-generated free radicals and TEAC (Trolox-Equivalent Antioxidant Capacity) assay. For this purpose, chromatographic and colorimetric methods were used. The majority compounds identified in PPE were flavan-3-ols (44.58%), flavonols (42.89%) and dihydrochalcones (11.60%). In PRF, we detected monomers and oligomers from dimers to heptamers, which were composed of 97% (−)-epicatechin and 3% (+)-catechin. The antioxidant potential was notably higher in PRF than in PPE. The (−)-epicatechin monomer and the procyanidin B2 dimer showed more ease in reducing peroxidase-generated free radicals compared to other compounds of the apple skin, whereas phloridzin dihydrochalcone produced prooxidant effects.

A new dihydrochalcone dimer, 2',4',3",2"',4"'-pentahydroxy-4-O-4"-tetrahydrobichalcone, given the name littorachalcone, was isolated from the aerial parts of Verbena littoralis H. B. K. along with two known flavonoids 4'-hydroxywogonin and 8,3'-dimethoxy-5,7,4'-trihydroxyflavone. Littorachalcone caused a significant enhancement of nerve growth factor-mediated neurite outgrowth from PC12D cells.

Two new C-benzylated dihydrochalcone derivatives, 4,2′,4′-trihydroxy-6′-methoxy-3′(2′′-hydroxybenzyl)dihydrochalcone (1) and 2′,4′-dihydroxy-4,6′-dimethoxy-3′(2′′-hydroxybenzyl)dihydrochalcone (2), along with six known flavonoid derivatives (3-8), a known dihydrochalcone dimer (9), three known aromatic esters (10–12), and one known aromatic amide (13), were isolated from the leaves of Melodorum siamensis. The structures of the compounds were elucidated by spectroscopic analysis, mainly 1D and 2D NMR techniques (1H, 13C, COSY, HMQC, and HMBC), as well as by comparison with literature data. The isolated compounds with a sufficient amount for biological assays were evaluated for their antimalarial, antimycobactirial, and cytotoxic activities. Compounds 1, 2, and 13 exhibited strong cytotoxicity against human tumor cell lines KB and NCI-H187, with IC50 values in the range of 0.66–7.16 µg/mL.

Detection of shiikuwasha (Citrus depressa Hayata) juice adulterated with calamondin (Citrus madurensis Lour.) juice was investigated by the analyses of (1) phloretin dihydrochalcone glucoside, 3',5'-di-C-β-glucopyranosylphloretin (PD) detected by thin-layer chromatography and high-performance liquid chromatography (HPLC), (2) polymethoxylated flavones (PMFs), included nobiletin, tangeretin, and sinensetin, detected by HPLC, and (3) γ-terpinene peak percentage obtained by headspace solid-phase microextraction gas chromatography with cryofocusing. PD was detected in calamondin juice (25.5 mg/100 mL) but not in shiikuwasha juice. Shiikuwasha juice contained higher levels of nobiletin (48.8 mg/100 mL) than calamondin juice (2.4 mg/100 mL). Shiikuwasha juice was characterized by containing a higher percentage of γ-terpinene (12.3%) than calamondin juice (0.7%). A discrimination function obtained by a linear discriminant analysis with PMFs and a peak ratio of [nobiletin/tangeretin] and γ-terpinene detected the adulteration with accuracies of 91.7%. These three chemical markers were useful to detect shiikuwasha juice that is suspected of being adulterated with calamondin juice.

Rooibos leaves and fine stems (Aspalathus linearis; Fabaceae) are increasingly enjoyed as herbal tea, largely in fermented (oxidised) red-brown form, but also in unfermented (unoxidised) green form. Rooibos is rich in antioxidant polyphenols, with the dihydrochalcone, aspalathin, as a major active ingredient. We used Caenorhabditis elegans as model organism to investigate the effect of rooibos extracts against oxidative stress in vivo. In a high glucose environment, C. elegans treated with rooibos extract exhibited an extended lifespan. Furthermore, green rooibos was a more potent antioxidant than red rooibos, probably due to its substantially higher aspalathin content. In addition, rooibos decreased acute oxidative damage caused by the superoxide anion radical generator, juglone, with aspalathin playing a major role in improving the survival rate of C. elegans. Quantitative real-time PCR results demonstrated that aspalathin targets stress and ageing related genes, reducing the endogenous intracellular level of ROS. These findings suggest that rooibos increases stress resistance and promotes longevity under stress, probably mediated via a regulation of the DAF-16/FOXO insulin-like signalling pathway, supporting some of the health claims put forward for rooibos tea.

This review focus on the phytochemical progress and biological studies of plants from the genus Balanophora (Balanophoraceae) over the past few decades, in which most plants growth in tropical and subtropical regions of Asia and Oceania, and nearly 20 species ranged in southwest China. These dioeciously parasitic plants are normally growing on the roots of the evergreen broadleaf trees, especially in the family of Leguminosae, Ericaceae, Urticaceae, and Fagaceae. The plants are mainly used for clearing away heat and toxic, neutralizing the effect of alcoholic drinks, and as a tonic for the treatment of hemorrhoids, stomachache and hemoptysis. And it has been used widely throughtout local area by Chinese people. Cinnamic acid derivative tannins, possessing a phenylacrylic acid derivative (e. g. caffeoyl, coumaroyl, feruloyl or cinnamoyl), which connected to the C(1) position of a glucosyl unit by O-glycosidic bond, are the characteristic components in genus Balanophora. In addition, several galloyl, caffeoyl and hexahydroxydiphenoyl esters of dihydrochalcone glucosides are found in B. tobiracola, B. harlandii, and B. papuana. Other compounds like phenylpropanoids, flavonoids, terpenoids and sterols are also existed. And their biological activities, such as radical scavenging activities, HIV inhibiting effects, and hypoglycemic effects are highlighted in the review.

The processed leaves and stems of Aspalathus linearis contain hydroxylated benzoic and cinnamic acids, luteolin, chrysoeriol, quercetin, isoquercitrin, the C–C linked β- d -glucopyranosides based on four flavones and the dihydrochalcone aspalathin.

From the farinose exudate of Pentagramma triangularis , two biflavonoids which are composed of a flavone and a dihydrochalcone nucleus, and linked through a methylene group were isolated in addition to five known flavonoids. The new structures were determined by means of spectroscopic analysis, in particular, by 2D NMR techniques.