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L'analyse des flavonoides du miel presente un interet pour etudier l'origine geographique et botanique du produit. Les divers echantillons de miel (50 g) ont ete melanges avec 5 parties d'eau (a pH 2 avec HCl) et filtres a travers une colonne Amberlite XAD-2 qui retient les flavonoides et elimine les sucres. Les flavonoides ont ete ensuite elues au methanol et l'eluat a ete concentre sous vide. La fraction sortante des flavonoides a ete analysee par chromatographie HPLC

This work was afforded from 2 points of view, phytochemical evaluation and relation to antioxidant activity and dietary burden of phenolics of a cup of “Mountain tea”, a drink obtained by domestic infusion of Sideritis. Phytochemically, two extraction protocols using water and methanol as solvent were used for comparison. Methanol and boiling water extracts (by domestic infusion procedure) showed that extracts were rich in bound forms of phenolics such as hydroxycinnamic acids, phenylethanoid glycosides and flavonoid glycosides. The total phenolic content for Sideritis species ranged around 190 mg per serving (2 g infusion bag) for methanol extracts and around 72 mg per serving in water extracts. Among the two different Macedonian Sideritis species, Sideritis raeseri (wild growing) showed the highest phenolics content in both extracts (212 mg and 89 mg per serving, respectively). Concerning the phenolic content in the different aerial parts, leaf was the richest plant organ in phenolics followed by flower and stem with the lowest amount. The methanol extract from Sideritis raeseri (wild growing) showed the highest antioxidant capacity as shown by DPPH, ABTS and FRAP assays. The antioxidant capacity was linearly correlated with phenolic content. Nutritionally, the dietary burden of phenolics of a “Mountain tea” bag for domestic infusion (serving size) was established at 89 mg for an homogeneous and equal distribution of the different aerial parts (leaf, flower and stem). However, and according to our results a rate of 60% leaf and 40% flower would increase the content of bioavailable phenolics and also the total phenolics content of a serving bag of “Mountain tea”.

Methyl anthranilate (MA) and hesperetin have been compared as markers for the floral origin of citrus honey. In the present work the contents of MA and hesperetin have been determined by GC and HPLC respectively in 18 honey samples produced in Mediterranean Spain. There was no correlation between the contents of MA and hesperetin. The concentration of MA ranged between 1.44 and 3.60 mg kg−1 while hesperetin ranged between 0.28 and 0.84 mg kg−1. These results support the hypothesis that hesperetin could be used as an additional marker in the determination of citrus honey origin.

Subject and Source Micromeria albanica (Gris. ex K. Maly) ~ilic, M. thymifolia (Scop.) Fritsch., M. dalrnadca Bentham, M. juliana (L.) Bentham ex Gris.,/14. cristata (Hampe) Gris., M. parviflora Reichenb., M. graeca (L.) Bentham, M. pseudocroatica ~ilic and M. croatica (Pers.) Schott. were collected in Yugoslavia. Vouchers are deposited in the Herbarium of the Botanical Institute and Garden at Belgrade.

From the stem bark of the halophytes Tamarix gallica , T. africana and T. bobeana , the new compound coniferyl alcohol 4-sulphate was isolated and identified by UV, IR, FAB-MS, 1 H and 13 C NMR techniques. Other cinnamyl alcohol sulphates were detected but their structures were not fully established. Phenolic sulphates were also present in other tissues of these plants. Coniferyl alcohol sulphate was found in another halophyte, Arthrocnemum fruticosum (Chenopodiaceae) suggesting that it could be a common storage precursor of lignin in woody halophytes. In addition, kaempferol 4′-methyl ether 3-sulphate, a new naturally occurring compound, and tamarixetin 3-sulphate were identified in the stem bark of the three Tamarix species.

The flavonoids, both external aglycones and vacuolar flavonoid glycosides, have been identified in the aerial parts of endemic North African Sideritis species. The flavonoids produced by these African species are very similar to those produced by Spanish species, being mainly 7-allosylglucosides of 8-hydroxyflavones. Two new flavonoid glycosides, apigenin and luteolin 7-allosylglucosides, have been identified in these plants. Species of the section Sideritis are characterized by the accumulation of the 7-glycosides of 8-hydroxyflavones (isoscutellarein, hypolaetin and their methyl ethers) whereas those of section Hesiodia accumulate 7-glycosides of the common flavones (apigenin, luteolin and chrysoeriol).

Key Word Index--Sider~s; Labiatae; excretory flavones; 8-hydmxyflavone glycosides; chemotaxonomy; phylogeny; ecology. Abstract--An HPLC and TLC analysis of the vacuolar and epicuticular flavonoids from Spanish Sideritis species has been carried out, and the distribution of these compounds has been used as a chemotaxonomic approach to the systematic prob- lems of this genus. Generally, a correlation between the flavonoid patterns and the morphological and genetic data has been found. Epicuticular flavonoids accumulate in the phyletically more advanced species while the primitive species were devoid of external flavonoids. Excretory flavonoids also seem to increase in species growing in semi-arid habitats.

The flavonoid compounds present in almond (Prunus amygdalus, Rosaceae), Jara (Cistus sp Cistaceae), Echium sp (Boraginaceae) and Chrysanthemum sp (Compositae) bee pollens have been studied by TLC, 2D PC and HPLC techniques. These bee pollens show characteristic flavonoid patterns which allow their use as biochemical markers of their plant origin. In addition, the flavonoid patterns of natural almond and ‚Jara’ pollens have been shown to be identical to those of the corresponding bee pollens confirming their use as chemical markers. The flavonoid aglycones obtained by acid hydrolysis of pollen flavonoids are also useful for identification purposes. Almond bee pollen contains 8-methoxykaempferol, kaempferol and quercetin 3-glycosides, ‚Jara’ bee pollen produces quercetin and isorhamnetin 3-glycosides and trace amounts of myricetin and kaempferol 3-glycosides, Echium bee pollen contains mostly kaempferol 3-glycosides and traces of quercetin 3-glycosides, and Chrysanthemum contains kaempferol, apigenin, and quercetin 3-glycosides. The major compound in almond pollen, namely 8-methoxykaempferol 3-glycoside, was not detected in the related apple, pear, cherry and plum pollens.

Sixteen free flavone aglycones exuded onto the leaf surfaces have been analysed in twenty-three taxa of genus Thymus growing in the Iberian Peninsula. A chemotaxonomic study of these compounds has been carried out. Correlations with morphological classifications and the usefulness of excreted flavonoids as taxonomic markers are discussed.

A leaf survey of 308 species belonging to the Labiatae, Scrophulariaceae and to five related families has shown that the common flavones, apigenin, luteolin and chrysoeriol are widely present, occurring especially as the 7-glucuronides. In addition 48 species (16% of sample) contain 8-hydroxyflavones and 131 species (43%) 6-hydroxy- or 6-methoxyflavones in glycosidic combination. The frequencies recorded are slightly higher than those found (35% for both groups) in earlier surveys. 8-Hydroxyflavones based on apigenin and luteolin are restricted to the Labiatae (5 genera), Scrophulariaceae ( Gratiola and Veronica ) and Lentibulariaceae ( Pinguicula ). In Labiatae, they only occur in the subfamily Lamoideae and not in the Nepetoideae. In Veronica , they are restricted to species in the sections Alsinebe and Chamaedrys . 6-Oxygenated flavones have a more sporadic distribution, but are consistently present in genera such as Scutellaria , Phlomis , Micromeria , Origanum and Thymus (Labiatae), in Parahebe (Scrophulariaceae) and Globularia (Globulariaceae). Although uncommon, flavonol glycosides were detected in a few species of the Labiatae, Scrophulariaceae and Globulariaceae, and C -glycosylflavones were detected in a few species of the former two families. The chemosystematic significance of these findings is discussed.

From the aerial parts of the maritime plant Lippia nodiflora , 15 flavonoids, 3 flavone aglycones and 12 new flavone sulphates, have been isolated and identified. The new flavone sulphates are mono- and disulphates of nepetin, jaceosidin, hispidulin, 6-hydroxyluteolin and nodifloretin present as the sodium salts. These sulphates are the only flavone conjugates detected in this plant. Flavone trisulphates are additionally present in populations of this species from Malaysia and Saudi Arabia, but lack of plant material prevented their complete characterization. Analysis of the closely related species Lippia canescens showed that it has the same flavonoid pattern. By contrast, a third species L. triphylla showed a flavonoid pattern lacking flavonoid sulphates, but characterized by the presence of 7-glucuronylglucosides of luteolin, diosmetin and apigenin. This is the first finding of flavonoid sulphates in the Verbenaceae.

A survey of aerial tissues of 42 European taxa of the genus Teucrium has revealed the widespread presence of five surface flavonoids: cirsiliol, cirsimaritin, cirsilineol, salvigenin and 5-hydroxy-6,7,3′,4′-tetramethoxyflavone. The latter two compounds are useful taxonomic markers in that salvigenin is characteristic of species of section Polium, while 5-hydroxy-6,7,3′,4′-tetramethoxyflavone is completely confined to species of the other five sections surveyed. Eleven flavone glycosides, four flavonol glycosides and the glycoflavone vicenin-2 were found to occur as vacuolar constituents. One of the flavone glycosides, cirsimaritin 4′-glucoside, only occurs in the species T. arduini, while two others, hypolaetin and isoscutellarein 7-acetyl-allosylglucosides, are characteristic of the closely related T. chamaedrys and T. webbianum. 6-Hydroxyluteolin is widely present as the 7-glucoside and 7-rhamnoside, the latter compound being a new glycoside. In general, the chemical results are correlated with sectional classification and usefully indicate that at least one taxon, T. compactum, is misplaced within the genus. Phyletically, the restriction of flavonol glycosides mainly to section Teucrium suggests that this may be the basic group within the genus.

The existence of sympatric interspecific hybrids of Sideritis serrata Cav. ex Lag. and S. bou r­ gaeana Boiss. Reut, has been shown by HPLC analysis of the flavonoid glycosides accumulated in the cell sap, and by the methylated flavonoid aglycones exudated by the plants and deposited onto the plant surfaces. The hybrids tend to produce in a single plant the compounds characteristic of the parental taxa. This “complementation” effect in the hybrids permitted relatively easy detec­tion of F1 hybrids. Generally, there was a close correlation between the biochemical results and a morphological analysis which used the Anderson’s index, although a specimen which morphologi­cally was a hybrid, showed a flavonoid pattern as S. bourgaeana. The external flavonoids analysis has revealed that the activity of sideritoflavone O -methyltransferases is much more important in S. serrata than in S. bourgaeana, while the hybrids show intermediate values. M oreover, S. bour­gaeana accumulates sideritoflavone 3′-m ethylether whereas S. serrata accum ulates the 4′-methylether. The hybrids produce both com pounds in similar amounts. In this study, external flavonoids have proved more useful than vacuolar flavonoid glycosides in the biochemical documentation of hybridization. This is probably due to the fact that methylated flavonoid aglycones are physiologi­cally more stable as they are externally located and therefore preserved from the action of enzymes.

Summary Background & aims Urolithins are microbial metabolites produced after consumption of ellagitannin-containing foods such as pomegranates and walnuts. Parallel to isoflavone-metabolizing phenotypes, ellagitannin-metabolizing phenotypes (urolithin metabotypes A, B and 0; UM-A, UM-B and UM-0, respectively) can vary among individuals depending on their body mass index (BMI), but correlations between urolithin metabotypes (UMs) and cardiometabolic risk (CMR) factors are unexplored. We investigated the association between UMs and CMR factors in individuals with different BMI and health status. Methods UM was identified using UPLC-ESI-qToF-MS in individuals consuming pomegranate or nuts. The associations between basal CMR factors and the urine urolithin metabolomic signature were explored in 20 healthy normoweight individuals consuming walnuts (30 g/d), 49 healthy overweight-obese individuals ingesting pomegranate extract (450 mg/d) and 25 metabolic syndrome (MetS) patients consuming nuts (15 g-walnuts, 7.5 g-hazelnuts and 7.5 g-almonds/d). Results Correlations between CMR factors and urolithins were found in overweight-obese individuals. Urolithin-A (mostly present in UM-A) was positively correlated with apolipoprotein A-I (P ≤ 0.05) and intermediate-HDL-cholesterol (P ≤ 0.05) while urolithin-B and isourolithin-A (characteristic from UM-B) were positively correlated with total-cholesterol, LDL-cholesterol (P ≤ 0.001), apolipoprotein B (P ≤ 0.01), VLDL-cholesterol, IDL-cholesterol, oxidized-LDL and apolipoprotein B:apolipoprotein A-I ratio (P ≤ 0.05). In MetS patients, urolithin-A only correlated inversely with glucose (P ≤ 0.05). Statin-treated MetS patients with UM-A showed a lipid profile similar to that of healthy normoweight individuals while a poor response to lipid-lowering therapy was observed in MB patients. Conclusions UMs are potential CMR biomarkers. Overweight-obese individuals with UM-B are at increased risk of cardiometabolic disease, whereas urolithin-A production could protect against CMR factors. Further research is warranted to explore these associations in larger cohorts and whether the effect of lipid-lowering drugs or ellagitannin-consumption on CMR biomarkers depends on individuals’ UM. Clinical Trial Registry numbers and websites NCT01916239 ( https://clinicaltrials.gov/ct2/show/NCT01916239 ) and ISRCTN36468613 ( http://www.isrctn.com/ISRCTN36468613 ).

In addition to the previously characterized amentoflavone and dihydroamentoflavone, two further biflavonoids have been identified from Isophysis tasmanica : hinokiflavone and podocarpusflavone A. This is the first time these two biflavonoids have been found in the monocotyledons. Amentoflavone has also been discovered in Xerophyta plicata ; this constitutes the first record of biflavonoids in Velloziaceae.

From the aerial parts of Helichrysum decumbens , three new antifungal phloroglucinol derivatives have been identified. Their structures have been established by UV, IR, EIMS, FAB-MS, 1 H NMR and 13 C NMR techniques. In addition, the highly methylated flavonoids 3,5-dihydroxy-6,7,8-trimethoxyflavone, 5,7-dihydroxy-3,6,8-trimethoxy-flavone and 3,5-dihydroxy-6,7-dimethoxyflavone have been detected, the latter being a new naturally occurring compound. The phloroglucinols prevented the growth of Cladosporium herbarum in a bio-assay. These secondary metabolises are externally deposited on the plant surfaces.

The occurrence of interspecific hybrids of Sideritis angustifolia and S. incana has been biochemically verified by TLC and HPLC analyses of external and internal flavonoids. A correlation between the excretion of flavonoids and the presence of glands in the taxa studied has been observed. The hybrids produce flavonoid patterns which contain the substances typical of both parents.

From the aerial parts of Helichrysum nitens , 5,7-dimethoxyflavone, 5,6,7-trimethoxyflavone, 3,5,7-trimethoxyflavone, 5,6,7,8-tetramethoxyflavone, 3,5,6,7-tetramethoxyflavone and 3,5,6,7,8-pentamethoxyflavone have been isolated and identified. In addition, 5-hydroxy-6,7-dimethoxyflavone and 5-hydroxy-6,7,8-trimethoxyflavone have also been found. The antifungal activities of the fully methylated compounds were similar to that of tangeretin (5,6,7,8,4′-pentamethoxyflavone), an antifungal flavonoid isolated from Citrus leaves. These compounds have been found externally deposited on the leaf and stem surfaces. 3,5,6,7,8-Pentamethoxyflavone is a new naturally occurring flavonoid.

The novel flavonol 8-methoxykaempferol 3-O-(2″-β- d -glucopyranosyl-β- d -glucopyranoside) has been found as a yellow pigment in almond pollen. In addition, trace amounts of kaempferol and quercetin 3-diglucosides have been detected. These compounds have been isolated from almond bee pollen, which is a convenient source for the study of flavonoids from natural pollen. HPLC studies show no differences in the flavonoid patterns of pollen and bee pollen, and demonstrate that 8-methoxykaempferol 3-sophoroside is the main flavonoid in almond pollen, while other flower and leaf tissues are devoid of this pigment. This compound is also absent from other botanically related pollens (plum, apple, cherry, and pear).

Poderia causar estranheza, — e não somente ao leigo — o fato de pretendermos nos servir do Epistolário de Agostinho como fonte principal para um estudo de maior envergadura acerca das idéias políticas do grande Doutor (354-430). É preciso, pois, salientar, logo de início, que suas cartas à nossa disposição hoje (cf. PL XXXIII — 270 cartas; CSEL LXXXVIII - 31 cartas) são não apenas confidenciais e pastorais, mas também doutrinais (filosófico-teológicas, as mais numerosas) e oficiais. Cobrem elas todo o arco da vida de Agostinho, a partir de sua conversão, e refletem o século agitado em que ele viveu: a decadência do Império Romano do Ocidente, sua vida econômica, política e religiosa.

For five new clones of pomegranate, culti- vated under homogeneous conditions, changes in juice anthocyanin contents during ripening were studied. Six anthocyanin pigments were found to be responsible for the red color of pomegranate juice. These were quanti- tatively and qualitatively analyzed by high-performance liquid chromatography and identified as delphinidin 3- glucoside and 3,5-diglucoside, cyanidin 3-glucoside and 3,5-diglucoside and pelargonidin 3-glucoside and 3,5-di- glucoside. Generally, there was an increase in juice pig- mentation during fruit ripening. In the early fruit-ripen- ing stages, delphinidin 3,5-diglucoside was the main pigment, followed by cyanidin 3,5-diglucoside, while in the later stages, the monoglucoside derivatives cyanidin 3-glucoside and delphinidin 3-glucoside increased con- siderably. The pelargonidin derivatives were always present in small amounts. Previous studies have shown that six anthocyanins are found in the juice of pomegranates, namely del- phinidin 3-glucoside and 3,5-diglucoside, cyanidin 3- glucoside and 3,5-diglucoside, and pelargonidin 3-glu- coside and 3,5-diglucoside (1). The peel contains only the pelargonidin and cyanidin derivatives, and no del- phinidin is detected (5). Anthocyanin content and evolution during the de- velopment and postharvest storage of pomegranates have been studied previously (1). During the first steps of development the 3,5-diglucosides are the main pig- ments present in the juice, with delphinidin glycosides being the main pigment type, while during the optimum harvesting time, the 3-glucosides are the main pigments and the cyanidin derivatives are the predominant com- pounds. The aim of the present work was to evaluate and quantify the anthocyanin content of five different pom- egranate clones with distinctive quality characteristics (acidity, color stability, etc.), and to follow the changes in juice pigmentation, both qualitatively and quantita- tively, during the development of the fruit. The effect of fruit location in the tree was also studied.

Minimally processed products are more perishable than unprocessed raw materials and readily deteriorate in quality, especially in color and texture. The effects of minimal processing on phenolic metabolites have been studied on red lettuce. Three different tissues of cv. Lollo Rosso were separated as white, green, and red and stored at 5 °C for 7−14 days. The phenolic acids caffeoyltartaric, chlorogenic, dicaffeoyltartaric, and dicaffeoylquinic, the flavonoids quercetin 3-glucuronide, quercetin 3-glucoside, quercetin 3-(6-malonylglucoside), and the new compound quercetin 3-(6-malonylglucoside) 7-glucoside, and the anthocyanin cyanidin 3-malonylglucoside were isolated and identified in lettuce extracts. Phenolic compound content was evaluated immediately after cutting and after storage of the minimally processed products at 5 °C. In midrib, wounding induced an increase in phenylpropanoids during storage, particularly phenolic acids and anthocyanins. On the contrary, wounding did not induce significant chan...

A simple mixture of anthocyanins was analysed by CZE, using a standard silica capillary with a pH 8 borate running buffer. Generally, the anthocyanins separated according to the nature of the aglycone and degree of glycosylation. A concentrated injection solution was required for detection at 580 nm, due to the small proportion of coloured quinonoidal base in the anthocyanin equilibrium mixture at this pH, the small injection volume and the short detector path-length used in this technique. It was observed that the ability to maintain a satisfactory current during analysis was critically dependent on the pH of the injection solution.

7 pages, 8 tables, 1 figure., Flavonoids, hydroxycinnamoyl derivatives (sinapic and ferulic acid derivatives+caffeoyl-quinic acid derivatives) and vitamin C were quantified by HPLC-MS in five commercial and three experimental cultivars from freshly harvested broccoli inflorescences ( Brassica oleracea L. var. italica). In order to identify differences due to genetic and agronomic factors, the broccoli cultivars were grown under different climatic and agronomic conditions, i.e. early (winter) and late (spring) seasons with poor (15 kg/ha) and rich (150 kg/ha) sulphur fertilisation. The predominant sinapic and ferulic acid derivatives in all broccoli cultivars were 1,2-diferuloylgentiobiose, 1,2,2'-trisinapoylgentiobiose and 1,2'-disinapoyl-2-feruloylgentiobiose. In addition, the compounds 1,2-diferuloylgentiobiose, 1-sinapoyl-2,2'-diferuloylgentiobiose and 1,2,2'-triferuloylgentiobiose were identified in broccoli inflorescences for the first time. Extreme agronomic and environmental conditions (late season and rich sulphur fertilisation which could induce different stress situations on the plant) enhanced the phenolic content. Thus, total flavonoids showed the highest content, followed by total sinapic and feruloyl acid derivatives and total caffeoyl-quinic acid derivatives. In general, cultivars grown under rich fertilisation and late season conditions showed higher vitamin C content than those grown under the poor and early ones. Finally, results showed that commercial cultivars rendered higher amounts of phenolic compounds and vitamin C than the experimental ones., The authors are grateful to Spanish CICYT (AGL2001–1125) and the Fundació n Séneca and Consejer a de Agricultura, Agua y Medio Ambiente (AGR/6/FS/99) for the financial support of this work.

Flavonoids and other phenolics of Tunisian honey samples and propolis were analyzed to find correlations between botanical and geographical origin and chemical composition. Flavonoid content of honey was very variable (20−2400 μg/100 g). The richest samples contained the characteristic propolis flavonoids, while those containing fewer flavonoids were devoid of these substances. This is a difference with honeys from temperate areas, in which the poplar-derived flavonoids are present in all honey samples. In Tunisian honeys, and propolis, a new flavonoid, myricetin 3,7,4‘,5‘-tetramethyl ether, was detected. This is characteristic of Cistus spp. leaf exudates. Another minor compound was identified as quercetin 3,7,3‘-trimethyl ether. They were present in high amounts in propolis but were only detected in small amounts in honey. These results show that in border areas, such as Tunisia, where poplars are not always available for propolis collection, other plant sources can be used and their constituents detect...

The flavonoids and other phenolics present in different commercial jams of apricot, peach, plum, strawberry, sour orange, apple, and pear have been studied, and the characteristic compounds for each different jam identified. As a general rule these substances do not differ from those found in the natural fruits. Every jam type generally has a distinctive flavonoid pattern characterized by the occurrence of one or more markers. The high sugar and pectin contents of fruit jams constitute an important problem in the extraction of phenolic compounds for analysis. This problem has been solved by filtration of the diluted original extracts through Amberlite XAD-2 resin columns

A study of external flavonoid aglycones and vacuolar flavonoid glycosides by HPLC, combined with morphological analyses (electron microscopy) of the hair covering, has shown the affinities between the Sideritis taxa growing in southern Portugal ( S. algarvensis Rivera) and S. maura which is endemic to northern Africa. The study has also revealed the differences between S. algarvensis and the Spanish species S. angustifolia and S. arborescens. Sideritis algarvensis was previously related to these Spanish species.

Urolithins (Uros) are gut microbiota-derived metabolites from ellagitannins and ellagic acid (EA), naturally occurring polyphenols abundantly found in pomegranate, tea, some berries, and nuts. EA e...

The conformational properties in solution of the prototype compound TSAO-T (1) and its two analogues 2 and 3 have been determined by H and C NMR techniques. The three compounds showed a sugar ring conformation rare among HIV-inhibitory nucleosides, probably due to the presence, at the 3'-position of the spiro moiety

The pigments of Salvia splendens flowers (scarlet cvs) have been identified as pelargonidin 3-caffeoylglucoside-5-dimalonylglucoside and pelargonidin 3-p-coumaroylglucoside-5-dimalonylglucoside. The flowers of S. coccinea contain the same pigments in the corolla but the calyx contains, in addition, the cyanidin analogues.