Bioverfügbarkeit und Biokinetik von Polyphenolen aus Rotwein (Lemberger) gegenüber rotem Traubensaft wurden in einem gemischten Kollektiv mit 9 gesunden Probanden im crossover Vergleich untersucht. Nach Verabreichung einer Einzeldosis entweder von 400 ml Rotwein oder 400 ml rotem Traubensaft mit abgestimmtem Gesamtanthozyangehalt (27,6 mg bzw. 283,5 mg) wurde der Plasmaspiegel von Anthozyaninglukosiden ebenso wie deren Harnausscheidungsrate in regelmässigen Intervallen HPLC analytisch ermittelt. Aus den Plasmawerten wurden biokinetische Parameter wie AUC, Maximalkonzentration cmax, deren Zeitpunkt tmax und die Halbwertszeit t1/2 abgeleitet. In der Harnausscheidung konnten Rmax (max. gemessene Ausscheidungsrate).deren Zeitpunkt tmax,R, Ae (Gesamtmenge ausgeschiedener Anthozyane) sowie der prozentuale Anteil der Aufnahmedosis Xe erfasst werden. In der Biokinetik der plasmatischen Anthozyane waren keine Unterschiede zwischen Rotwein und rotem Traubensaft zu erkennen, dagegen übertraf die Anthozyanausscheidungsrate nach Traubensaftzufuhr mit 0,23% der Aufnahmedosis signifikant diejenige nach Rotweinzufuhr mit 0,18% der Aufnahmedosis. Signifikant erhöht war auch das antioxidative Potential im Plasma (TRAP-test) nach Traubensafteinnahme gegenüber Rotwein. Es zeigte sich, dass Anthozyane aus roten Trauben zu geringem Anteil als intakte Glukoside resorbiert und als solche im Harn ausgeschieden werden. Roter Traubensaft scheint wenigstens gleich- oder sogar höherwertig gegenüber dem getesteten Rotwein zu sein im Vergleich der nachweisbaren, bioaktiven Inhaltsbestandteile.

The concentration and the composition of secondary plant metabolites are strictly dependent on the apple varieties. In this study, twelve cloudy apple juices made from nine different cider apple cultivars of the harvests from 2001 to 2003 were produced and characterized analytically. The average values for total polyphenols (Folin and HPLC) were 1237 mg/l (822-2161 mg/l), and 520 mg/l (197-1229 mg/l), respectively. With antioxidant capacities up to 20 mmol Trolox/l (Mean 10 mmol/l, range 6-20 mmol/l), some of them matched or exceeded the values of red wine. The cultivars Bittenfelder and Bohnapfel showed the highest polyphenol concentrations. In comparison with commercial apple juices, the analyses of other chemical parameters revealed some peculiarities of apple juices made from special cider cultivars. For the sake of comparison, also apple juices of four dessert apples cultivars were investigated (Golden Delicious, Cox Orange, Granny Smith and Topaz). The polyphenol concentrations of 316-736 mg/l (Folin) and 22-221 mg/l (HPLC), respectively, as well as the antioxidative capacities (1-4 mmol/l Trolox) were far below that of cider apple varieties. The average value for the polyphenols (HPLC) of 102 mg/l in dessert apple juices was lower by a factor of five, compared to cider apple juice (average value 520 mg/l, HPLC). Boskoop had an antioxidative capacity of 6 mmol/l Trolox which is between dessert apple juices and cider apple juices. Four versions of juice were made from each table apple cultivar: cloudy direct juice, cloudy juice from concentrate, clear direct juice and clear juice from concentrate. The juices from concentrate did not differ from the direct juices in polyphenols and antioxidant capacity. On the other hand, the clarification of the apple juices had a pronounced effect on polyphenol contents and antioxidant capacities. The latter were up to 70% lower than the contents in the corresponding cloudy juices of the same cultivar. The quality of apple juice may generally be improved by using varieties with high concentrations of secondary plant metabolites. Cider apple cultivars had better antioxidant capacity than most of the commercial juices and can be used in apple juice blends. In consideration of functional fruit juices or fruit based beverages the genetic pool of classical apple varieties has to be preserved.

The concentration and the composition of secondary plant metabolites are strictly dependent on the apple varieties. In this study, twelve cloudy apple juices made from nine different cider apple cultivars of the harvests from 2001 to 2003 were produced and characterized analytically. The average values for total polyphenols (Folin and HPLC) were 1237 mg/l (822-2161 mg/l), and 520 mg/l (197-1229 mg/l), respectively. With antioxidant capacities up to 20 mmol Trolox/l (Mean 10 mmol/l, range 620 mmol/l), some of them matched or exceeded the values of red wine. The cultivars Bittenfelder and Bohnapfel showed the highest polyphenol concentrations. In comparison with commercial apple juices, the analyses of other chemical parameters revealed some peculiarities of apple juices made from special cider cultivars.For the sake of comparison, also apple juices of four dessert apples cultivars were investigated (Golden Delicious, Cox Orange, Granny Smith and Topaz). The polyphenol concentrations of 316-736 mg/l (Folin) and 22-221 mg/l (HPLC), respectively, as well as the antioxidative capacities (1-4 mmol/l Trolox) were far below that of cider apple varieties. The average value for the polyphenols (HPLC) of 102 mg/l in dessert apple juices was lower by a factor of five, compared to cider apple juice (average value 520 mg/l, HPLC). Boskoop had an antioxidative capacity of 6 mmol/l Trolox which is between dessert apple juices and cider apple juices. Four versions of juice were made from each table apple cultivar: cloudy direct juice, cloudy juice from concentrate, clear direct juice and clear juice from concentrate. The juices from concentrate did not differ from the direct juices in polyphenols and antioxidant capacity. On the other hand, the clarification of the apple juices had a pronounced effect on polyphenol contents and antioxidant capacities. The latter were up to 70% lower than the contents in the corresponding cloudy juices of the same cultivar.The quality of apple juice may generally be improved by using varieties with high concentrations of secondary plant metabolites. Cider apple cultivars had better antioxidant capacity than most of the commercial juices and can be used in apple juice blends. In consideration of functional fruit juices or fruit based beverages the genetic pool of classical apple varieties has to be preserved.

The aim of the present study was to assess the renal excretion of red beet juice (RBJ) antioxidants in six healthy humans. After a single oral dose of RBJ. The pharmacokinetic parameters obtained from urine were compared to those obtained after ingestion of water on an intra-individual basis. Urine was collected in intervals up to 24h post-intake. After RBJ ingestion, the betacyanins betanin and isobetanin were excreted in the volunteers’ urine (0.28% of the administered dose) and unambiguously identified by HPLC–ESI-MS/MS. Compared to the ingestion of water, RBJ consumption resulted in a significantly increased urinary excretion of total phenolics (51.1% of the administered phenolics) and other antioxidant compounds (43.9% of the administered compounds) within 24h.

We investigated the urinary pharmacokinetics of monomeric anthocyanins in seven healthy volunteers. The volunteers were administered a single oral dose of 3.57 g total anthocyanins contained in 150 ml of a concentrated elderberry juice under fasting conditions. Within 24 h the urinary excretion of unchanged cyanidin-3,5-diglucoside (cyanidin-3-sambubioside-5-glucoside and cyanidin-3,5-diglucoside were calculated as cyanidin-3,5-diglucoside equivalents), cyanidin-3-glucoside, cyanidin-3-sambubioside and total anthocyanins (i.e., the sum of all quantifiable anthocyanidin glycosides) was 0.16, 0.06, 0.05 and 0.06% of the administered doses, respectively. Maximum excretion rates were determined within 1.0 h after intake. The estimates (arithmetic mean +/- SD) of t(1/2) were 1.25 +/- 0.25, 1.53 +/- 0.36, 1.38 +/- 0.20 and 1.35 +/- 0.18 h for cyanidin-3,5-diglucoside, cyanidin-3-glucoside, cyanidin-3-sambubioside and total anthocyanins, respectively. The urinary excretion of intact anthocyanins was fast and the decline of excretion rates appeared to be monophasic, suggesting a one-compartment pharmacokinetic model, The low urinary excretion of dietary anthocyanidin glycosides with values below 1% indicates that a large proportion of these plant pigments consumed are metabolized before entry into the circulation.

The aim of the present pilot study was to characterise the renal elimination of betalains after consumption of red beet juice (RBJ). Six healthy, non-smoking female volunteers were given a single oral dose of either 500 mL of a commercial RBJ containing 362.7 mg of betalains and 500 mL of tap water, respectively, in a sequential manner. Urine was collected in intervals up to 24 h post-dose. Renal excretion of betalains was determined spectrophotometrically and quantified as betanin-equivalents. In addition, the identity of individual compounds was confirmed by HPLC coupled with diode-array detection and positive ion electrospray mass spectrometry, respectively. The amount (mean+/-S.D.) of intact betalains (betanin and isobetanin) recovered in urine was 1001+/-273 microg corresponding to 0.28+/-0.08% of the administered dose. Maximum excretion rates were observed after a median tmax,R of 3.0 h (range 2.5-8.0 h) amounting to 91.7+/-30.1 microg/h. The terminal elimination rate constant (lambdaz) and the corresponding half-life were 0.097+/-0.021 h(-1) and 7.43+/-1.47 h, respectively. Using the lambdaz estimates obtained the expected total betalain amount excreted in urine was 1228+/-291 microg. Based on the results obtained it is assumed that either the bioavailability of the betalains is low or that renal clearance is a minor route of systemic elimination for these compounds. The urinary excretion rates of unmetabolised betalains were fast and appeared to be monoexponential suggesting a one-compartment model. In order to get a more complete picture of the pharmacokinetics and health-promoting properties of red beet betalains, quantitative data on betalain bioavailability should include measurements of unchanged compounds and their corresponding metabolites in plasma, urine and bile.

The aims of the present study were to asses the renal excretion characteristics of elderberry anthocyanins, and to determine whether the consumption of elderberry juice would enhance postprandial plasma antioxidant status in healthy humans. In eight healthy subjects receiving a single oral dose of elderberry juice, the pharmacokinetic parameters were obtained from 7 h urine excretion. The mean fraction of orally ingested total anthocyanins (sum of cyanidin-3-sambubioside and cyanidin-3-glucoside) excreted unchanged with values of 0.033%, 0.038% and 0.040% after ingestion of 361, 541 and 722 mg, respectively, did not differ significantly (p>0.05). This is suggestive of a dose-independent urinary excretion of elderberry anthocyanins. Furthermore, plasma antioxidant capacity and total phenolics were significantly increased 1 h after ingestion of 400 ml of elderberry juice. Anthocyanins as the characteristic phenolic compounds in elderberries and elderberry juice were detected as unchanged glycosides in the volunteers’ plasma post-intake.

In a comparative study, 9 healthy volunteers ingested a single oral dose of 400 mL red grape juice or red wine with dose-adjusted anthocyanin content (283.5 mg or 279.6 mg, resp) in crossover. The content of anthocyanin glucosides was detected in plasma and urinary excretion. Additionally, the plasmatic antioxidant activity was assessed after intake. Based on the plasma content, biokinetic criteria of the single anthocyanins were calculated, such as AUC, c(max), t(max), and the elimination rate t(1/2). The urinary excretion of total anthocyanins differed significantly and amounted to 0.18% (red wine) and 0.23% (red grape juice) of the administered dose. Additionally, the plasmatic antioxidant activity increased to higher levels after juice ingestion compared to wine. The intestinal absorption of the anthocyanins of red grape juice seemed to be improved compared to red wine, suggesting a possible synergistic effect of the glucose content of the juice. The improved absorption resulted in an enhanced plasmatic bioactivity.

The aim of this study was to investigate the effect of different types of tomato processing on contents of lycopene, beta-carotene, and alpha-tocopherol. Samples of tomato sauce, tomato soup, baked tomato slices, and tomato juice were taken at different times of heating, respectively, after each step of production. HPLC was used to analyze contents of carotenoids and vitamin E. Due to the loss of water during thermal processing, contents of lycopene, beta-carotene, and alpha-tocopherol on a wet weight basis increased. On a dry weight basis, contents of lycopene increased or decreased depending on the origin of the tomatoes used, whereas the beta-carotene contents decreased or were quite stable. In contrast to lycopene, beta-carotene isomerized due to thermal processing. The alpha-tocopherol contents significantly rose during short-term heating. The increase was not caused by release of alpha-tocopherol from the seeds containing predominantly gamma-tocopherol and accounting for 2% of total alpha-tocopherol content only.

In a pilot study with 6 females and 1 male, the metabolism of various cyanidin glucosides after oral administration of elderberry juice was investigated. The anthocyanin metabolites were detected in urinary excretion. After ingestion of a bolus quantity of 3.57 g total anthocyanins in a 150 mL elderberry juice concentrate, 0.053% of the administered dose was excreted in urine as glucosidically bound cyanidins within the first 5 hours. Only 0.003% of the ingested anthocyanin glucosides was excreted as cyanidin glucuronide, suggesting that this conversion step might be of minor importance in urinary excretion.

Twelve food additives and six secondary plant products were analysed on their antioxidant activity by using three different test systems (Trolox equivalent antioxidant capacity, photochemiluminescence, ferric reducing antioxidant power). The results differed depending on the assay. All the food additives showed antioxidant activities comparable to the calibration substance Trolox. In contrast, the secondary plant products had an up to 16 times higher antioxidant potential. This might present a good reason for the food industry to use natural antioxidants instead of synthetic ones to get storage stability for processed food items – which, according to recent surveys, is in the interest of consumers.