The Experts below are selected from a list of 14430 Experts worldwide ranked by ideXlab platform

Volker Böhm - One of the best experts on this subject based on the ideXlab platform.

  • use of photochemiluminescence for the determination of antioxidant activities of carotenoids and antioxidant capacities of selected Tomato Products
    Journal of Agricultural and Food Chemistry, 2014
    Co-Authors: Jasmin Bauerfeind, Victoria Hintze, Josephine Kschonsek, Margrit Killenberg, Volker Böhm
    Abstract:

    The purpose of this study was to compare the antioxidant activity of carotenoids to that of α-tocopherol by using a photochemiluminescence method (PCL). Comparisons to results obtained by using other established methods (α-TEAC, FRAP, DPPH, LPSC) were carried out. A relationship between the chemical structure of carotenoids and their antioxidant activity could be discussed. The number of conjugated double bonds and functional groups had a positive influence. Additionally, the lipophilic antioxidant capacities of selected Tomato Products were analyzed using PCL and α-TEAC. HPLC was used to identify and quantify contents of carotenoids, tocopherols, and tocotrienols. The raw material fresh Tomatoes had the lowest antioxidant effect in both assays due to the lower carotenoid content. Tomato ketchup had the highest AOC in PCL, and Tomato puree, in α-TEAC. The antioxidant capacities were mainly dependent on the water content of the samples. Furthermore, a concentration-dependent effect could be observed in bot...

  • Lack of effects of Tomato Products on endothelial function in human subjects: results of a randomised, placebo-controlled cross-over study.
    British Journal of Nutrition, 2010
    Co-Authors: Verena Stangl, Claudia Kuhn, Sonja Hentschel, Nicoline Jochmann, Christine Jacob, Christine Gericke, Volker Böhm, Lars Muller, Kati Frohlich, Mario Lorenz
    Abstract:

    Epidemiological studies suggest that consumption of Tomato Products reduces the risk of CVD via antioxidant, hypocholesterolaemic and anti-inflammatory mechanisms. Although experimental data also describe beneficial effects on endothelial function, clinical data in human subjects are lacking. To test the hypothesis that Tomato ingestion ameliorates endothelial function, we randomised healthy non-smoking postmenopausal women to consume a buttered roll with and without Tomato puree (70 g) in a cross-over design. Endothelial-dependent flow-mediated dilation (FMD) and endothelial-independent nitro-mediated dilation of the brachial artery were assessed with high-resolution ultrasound (13 MHz linear array transducer). Acute (24 h) and long-term (7 d) effects were examined after daily consumption of the described meal. Nineteen volunteers completed the protocol and provided technically suitable ultrasound measurement data. Plasma lycopene levels increased from 0·30 ( sem 0·04) (baseline) to 0·42 ( sem 0·04) and to 0·74 ( sem 0·06) μ m after 24 h and 7 d, respectively, with Tomato puree consumption. These data indicated an effective absorption of the Tomato product. However, both acute and long-term Tomato puree consumption had no effects on endothelium-dependent or -independent dilation of the brachial artery. In addition, we found no correlation between lycopene plasma levels and FMD. In conclusion, consumption of Tomato Products associated with a significant increase in plasma lycopene levels had no effects on endothelial function in healthy postmenopausal women.

  • effects of ingestion of Tomatoes Tomato juice and Tomato puree on contents of lycopene isomers tocopherols and ascorbic acid in human plasma as well as on lycopene isomer pattern
    British Journal of Nutrition, 2006
    Co-Authors: Kati Frohlich, Karin Kaufmann, R Bitsch, Volker Böhm
    Abstract:

    Tomatoes are an important part of the diet. Lycopene, the predominant carotenoid in Tomatoes, is hypothesised to mainly mediate the health ben-efits of Tomato Products. Anticancer activity of Tomato Products and lycopene has been suggested by numerous studies. The aim of the presentstudy was to investigate the effect of ingestion of three different Tomato-based foodstuffs on plasma contents of lycopene, tocopherols and ascorbicacid. Because isomers of lycopene may have different biological activities, a special interest was to look how the lycopene isomer pattern is chan-ged depending on the matrix of Tomato Products. Following a 2-week depletion phase volunteers ingested 12·5mg lycopene/d for 4 weeks com-prising Tomatoes, Tomato juice or Tomato pure´e. The basal levels of lycopene in plasma were comparable for all groups and decreased significantlyduring the 2 weeks of depletion to approximately half of the basal values. Following intervention, plasma lycopene concentration increased sig-nificantly. Conversely, supplementation did not significantly affect levels of tocopherols and ascorbic acid in plasma. Regarding isomers of lyco-pene, the (Z)-lycopene:(all-E)-lycopene plasma isomer ratio was significantly changed during the study for all groups. A remarkable enrichment ofthe relative contents of (5Z)-lycopene was observed during the depletion period, which supports the hypothesis that lycopene (Z)-isomers areformed within the human body after ingestion of (all-E)-lycopene. After dietary intervention with lycopene-rich Products the isomer ratios returnedto those observed at the start of the study. Further investigations will clarify the process of isomerisation in more detail.Tomato Products: (all-E)-Lycopene: Lycopene (Z)-isomers: Ascorbic acid: Tocopherols: Human bioavailability

  • effects of ingestion of Tomatoes Tomato juice and Tomato puree on contents of lycopene isomers tocopherols and ascorbic acid in human plasma as well as on lycopene isomer pattern
    British Journal of Nutrition, 2006
    Co-Authors: Kati Frohlich, Karin Kaufmann, R Bitsch, Volker Böhm
    Abstract:

    Tomatoes are an important part of the diet. Lycopene, the predominant carotenoid in Tomatoes, is hypothesised to mainly mediate the health benefits of Tomato Products. Anticancer activity of Tomato Products and lycopene has been suggested by numerous studies. The aim of the present study was to investigate the effect of ingestion of three different Tomato-based foodstuffs on plasma contents of lycopene, tocopherols and ascorbic acid. Because isomers of lycopene may have different biological activities, a special interest was to look how the lycopene isomer pattern is changed depending on the matrix of Tomato Products. Following a 2-week depletion phase volunteers ingested 12.5 mg lycopene/d for 4 weeks comprising Tomatoes, Tomato juice or Tomato puree. The basal levels of lycopene in plasma were comparable for all groups and decreased significantly during the 2 weeks of depletion to approximately half of the basal values. Following intervention, plasma lycopene concentration increased significantly. Conversely, supplementation did not significantly affect levels of tocopherols and ascorbic acid in plasma. Regarding isomers of lycopene, the (Z)-lycopene:(all-E)-lycopene plasma isomer ratio was significantly changed during the study for all groups. A remarkable enrichment of the relative contents of (5Z)-lycopene was observed during the depletion period, which supports the hypothesis that lycopene (Z)-isomers are formed within the human body after ingestion of (all-E)-lycopene. After dietary intervention with lycopene-rich Products the isomer ratios returned to those observed at the start of the study. Further investigations will clarify the process of isomerisation in more detail.

Edward Giovannucci - One of the best experts on this subject based on the ideXlab platform.

  • lycopene Tomato Products and prostate cancer incidence a review and reassessment in the psa screening era
    Journal of Oncology, 2012
    Co-Authors: Melissa Y Wei, Edward Giovannucci
    Abstract:

    Lycopene has been proposed to protect against prostate cancer through various properties including decreased lipid oxidation, inhibition of cancer cell proliferation, and most notably potent antioxidant properties. Epidemiologic studies on the association between lycopene and prostate cancer incidence have yielded mixed results. Detection of an association has been complicated by unique epidemiologic considerations including the measurement of lycopene and its major source in the diet, Tomato Products, and assessment of prostate cancer incidence and progression. Understanding this association has been further challenging in the prostate-specific antigen (PSA) screening era. PSA screening has increased the detection of prostate cancer, including a variety of relatively indolent cancers. This paper examines the lycopene and prostate cancer association in light of epidemiologic methodologic issues with particular emphasis on the effect of PSA screening on this association.

  • changes in plasma and oral mucosal lycopene isomer concentrations in healthy adults consuming standard servings of processed Tomato Products
    Nutrition and Cancer, 2003
    Co-Authors: Charlotte Moxley Allen, Steven J Schwartz, Edward Giovannucci, Neal E Craft, Valerie L De Groff, Steven K Clinton
    Abstract:

    The consumption of Tomato Products is associated with a reduced risk of cardiovascular disease and several cancers. It is hypothesized that lycopene, the major carotenoid in Tomato Products, may mediate this relationship. We designed a study to examine changes in plasma and buccal mucosal cell (BMC) lycopene concentrations in healthy adults consuming standard daily servings of processed Tomato Products: spaghetti sauce, Tomato soup, or vegetable juice. Thirty-six healthy subjects consumed a lycopene-free diet for 2 wk and were then assigned to one of three (n = 12) intervention groups consuming daily, single servings of sauce (21 mg lycopene per ½ cup), soup (12 mg lycopene per 1 cup), or juice (17 mg lycopene per 8 oz) for 4 wk. Fasting blood and BMC samples were evaluated by high-performance liquid chromatography analysis for carotenoids and lycopene isomers. Total plasma lycopene concentrations (Mean ± SEM) decreased from 1.05 ± 0.07 to 0.54 ± 0.05 mmol/l (49%, P < 0.0001) during the 2-wk washout perio...

  • a prospective study of Tomato Products lycopene and prostate cancer risk
    Journal of the National Cancer Institute, 2002
    Co-Authors: Edward Giovannucci, Eric B Rimm, Yan Liu, Meir J Stampfer, Walter C Willett
    Abstract:

    Background: Some data, including our findings from the Health Professionals Follow-Up Study (HPFS) from 1986 through January 31, 1992, suggest that frequent intake of Tomato Products or lycopene, a carotenoid from Tomatoes, is associated with reduced risk of prostate cancer. Overall, however, the data are inconclusive. We evaluated additional data from the HPFS to determine if the association would persist. Methods: We ascertained prostate cancer cases from 1986 through January 31, 1998, among 47365 HPFS participants who completed dietary questionnaires in 1986, 1990, and 1994. We used pooled logistic regression to compute multivariate relative risks (RR) and 95% confidence intervals (CIs). All statistical tests were two-sided. Results: From 1986 through January 31, 1998, 2481 men in the study developed prostate cancer. Results for the period from 1992 through 1998 confirmed our previous findings-that frequent Tomato or lycopene intake was associated with a reduced risk of prostate cancer. Similarly, for the entire period of 1986 through 1998, using the cumulative average of the three dietary questionnaires, lycopene intake was associated with reduced risk of prostate cancer (RR for high versus low quintiles = 0.84; 95% CI = 0.73 to 0.96; P trend = .003); intake of Tomato sauce, the primary source of bioavailable lycopene, was associated with an even greater reduction in prostate cancer risk (RR for 2+ servings/week versus <1 serving/month = 0.77; 95% CI = 0.66 to 0.90; P trend <.001), especially for extraprostatic cancers (RR = 0.65; 95% CI = 0.42 to 0.99). These associations persisted in analyses controlling for fruit and vegetable consumption and for olive oil use (a marker for Mediterranean diet) and were observed separately in men of Southern European or other Caucasian ancestry. Conclusion: Frequent consumption of Tomato Products is associated with a lower risk of prostate cancer. The magnitude of the association was moderate enough that it could be missed in a small study or one with substantial errors in measurement or based on a single dietary assessment.

  • Tomato Products lycopene and prostate cancer risk
    Urologic Clinics of North America, 2002
    Co-Authors: Elizabeth C Miller, Edward Giovannucci, John W Erdman, Robert R Bahnson, Steven K Clinton
    Abstract:

    Several case-control and large prospective studies focusing on dietary assessment suggest that the intake of Tomatoes and Tomato Products may be associated with a lower risk of prostate cancer [18]. Although less certain at present, the accumulated data suggest that the benefit may be most pronounced in the protection against more advanced or aggressive prostate cancer. It is possible that lycopene is one of the compounds in raw and processed Tomato Products that may contribute to a lower risk of prostate cancer; however, this hypothesis remains to be further investigated. Other carotenoids and phytochemicals in Tomato Products may also contribute to the proposed health benefits. Food processing does not seem to reduce the benefits but may, in fact, enhance the bioavailability of beneficial components. The reported correlations or associations between the consumption of Tomato Products and prostate cancer risk should not be interpreted as causal until additional data are available from a variety of studies in different populations. Ideally, randomized controlled intervention studies would provide an ultimate test of the Tomato/lycopene hypothesis; however, the expense, long duration of exposure, and the near universal consumption of Tomato Products among Americans make a dietary intervention study difficult to undertake. It is reasonable to recommend to the general population the consumption of Tomato Products at approximately one serving per day or five servings per week as part of an overall healthy dietary pattern that may reduce the risks of prostate cancer, other malignancies, or other chronic diseases. This recommendation is consistent with current dietary guidelines to increase fruit and vegetable consumption to lower the risk of heart disease and many types of cancer [38]. Nutritional prevention of prostate cancer is very different from the use of dietary or nutritional treatments for established prostate cancer. The use of lycopene and other extracts for the treatment of prostate cancer is a separate issue that warrants individual attention and investigation.

Steven K Clinton - One of the best experts on this subject based on the ideXlab platform.

  • a comparison of plasma and prostate lycopene in response to typical servings of Tomato soup sauce or juice in men before prostatectomy
    British Journal of Nutrition, 2015
    Co-Authors: Elizabeth Grainger, Nancy E Moran, Ken M Riedl, Craig W Hadley, Michael C Gong, Kamal S Pohar, Steven K Clinton
    Abstract:

    : Tomato product consumption and estimated lycopene intake are hypothesised to reduce the risk of prostate cancer. To define the impact of typical servings of commercially available Tomato Products on resultant plasma and prostate lycopene concentrations, men scheduled to undergo prostatectomy (n 33) were randomised either to a lycopene-restricted control group ( < 5 mg lycopene/d) or to a Tomato soup (2-2¾ cups prepared/d), Tomato sauce (142-198 g/d or 5-7 ounces/d) or vegetable juice (325-488 ml/d or 11-16·5 fluid ounces/d) intervention providing 25-35 mg lycopene/d. Plasma and prostate carotenoid concentrations were measured by HPLC. Tomato soup, sauce and juice consumption significantly increased plasma lycopene concentration from 0·68 (sem 0·1) to 1·13 (sem 0·09) μmol/l (66 %), 0·48 (sem 0·09) to 0·82 (sem 0·12) μmol/l (71 %) and 0·49 (sem 0·12) to 0·78 (sem 0·1) μmol/l (59 %), respectively, while the controls consuming the lycopene-restricted diet showed a decline in plasma lycopene concentration from 0·55 (sem 0·60) to 0·42 (sem 0·07) μmol/l ( - 24 %). The end-of-study prostate lycopene concentration was 0·16 (sem 0·02) nmol/g in the controls, but was 3·5-, 3·6- and 2·2-fold higher in Tomato soup (P= 0·001), sauce (P= 0·001) and juice (P= 0·165) consumers, respectively. Prostate lycopene concentration was moderately correlated with post-intervention plasma lycopene concentrations (r 0·60, P =0·001), indicating that additional factors have an impact on tissue concentrations. While the primary geometric lycopene isomer in Tomato Products was all-trans (80-90 %), plasma and prostate isomers were 47 and 80 % cis, respectively, demonstrating a shift towards cis accumulation. Consumption of typical servings of processed Tomato Products results in differing plasma and prostate lycopene concentrations. Factors including meal composition and genetics deserve further evaluation to determine their impacts on lycopene absorption and biodistribution.

  • the consumption of processed Tomato Products enhances plasma lycopene concentrations in association with a reduced lipoprotein sensitivity to oxidative damage
    Journal of Nutrition, 2003
    Co-Authors: Steven K Clinton, Craig W Hadley
    Abstract:

    Lycopene, the predominant carotenoid in Tomatoes, is hypothesized to mediate the health benefits of Tomato Products. We designed a study to examine the change in plasma lycopene and resistance of lipoproteins to ex vivo oxidative stress. Healthy individuals (n = 60; age >40 y; 30 men/30 women) consumed a lycopene-free diet for 1 wk and were subsequently randomized to receive 35 +/- 1, 23 +/- 1 or 25 +/- 1 mg lycopene/d from Campbell's Condensed Tomato Soup (CS), Campbell's Ready To Serve Tomato Soup (RTS) or V8 Vegetable Juice (V8), respectively, for 15 d. Total plasma lycopene concentrations decreased from 0.499 +/- 0.044 to 0.322 +/- 0.027 (35%, P < 0.0001) micro mol/L for the 60 participants during the 7-d washout period. After intervention, total lycopene concentrations increased for those consuming CS, RTS and V8 (compared with the washout period for each group) to 0.784 +/- 0.083 (123%, P < 0.0001), 0.545 +/- 0.061 (57%, P < 0.01) and 0.569 +/- 0.061 (112%, P < 0.0001) micro mol/L, respectively. The concentrations of all lycopene isomers decreased during the washout period. As a percentage of plasma total lycopene isomers for the 60 subjects, all-trans-lycopene decreased from 44.4 +/- 1.2 to 39.6 +/- 1.2 (P < 0.0001), whereas total cis-lycopene isomers increased from 55.6 +/- 1.2 to 60.4 +/- 1.2 (P < 0.0001) during the washout period, a shift that was reversed by consumption of Tomato Products for 15 d. The ex vivo lipoprotein oxidation lag period, used as a measure of antioxidant capacity, increased significantly from 64.7 +/- 2.4 min at the end of the washout period (all groups) to 70.1 +/- 4.0 (P < 0.05), 68.3 +/- 2.4 (P < 0.05) and 71.7 +/- 4.0 min (P < 0.01) after treatment for the CS, RTS and V8 groups, respectively. This study shows that lycopene concentrations and isomer patterns change rapidly with variation in dietary intake. In addition, 15 d of Tomato product consumption significantly enhanced the protection of lipoproteins to ex vivo oxidative stress.

  • changes in plasma and oral mucosal lycopene isomer concentrations in healthy adults consuming standard servings of processed Tomato Products
    Nutrition and Cancer, 2003
    Co-Authors: Charlotte Moxley Allen, Steven J Schwartz, Edward Giovannucci, Neal E Craft, Valerie L De Groff, Steven K Clinton
    Abstract:

    The consumption of Tomato Products is associated with a reduced risk of cardiovascular disease and several cancers. It is hypothesized that lycopene, the major carotenoid in Tomato Products, may mediate this relationship. We designed a study to examine changes in plasma and buccal mucosal cell (BMC) lycopene concentrations in healthy adults consuming standard daily servings of processed Tomato Products: spaghetti sauce, Tomato soup, or vegetable juice. Thirty-six healthy subjects consumed a lycopene-free diet for 2 wk and were then assigned to one of three (n = 12) intervention groups consuming daily, single servings of sauce (21 mg lycopene per ½ cup), soup (12 mg lycopene per 1 cup), or juice (17 mg lycopene per 8 oz) for 4 wk. Fasting blood and BMC samples were evaluated by high-performance liquid chromatography analysis for carotenoids and lycopene isomers. Total plasma lycopene concentrations (Mean ± SEM) decreased from 1.05 ± 0.07 to 0.54 ± 0.05 mmol/l (49%, P < 0.0001) during the 2-wk washout perio...

  • Tomato Products lycopene and prostate cancer risk
    Urologic Clinics of North America, 2002
    Co-Authors: Elizabeth C Miller, Edward Giovannucci, John W Erdman, Robert R Bahnson, Steven K Clinton
    Abstract:

    Several case-control and large prospective studies focusing on dietary assessment suggest that the intake of Tomatoes and Tomato Products may be associated with a lower risk of prostate cancer [18]. Although less certain at present, the accumulated data suggest that the benefit may be most pronounced in the protection against more advanced or aggressive prostate cancer. It is possible that lycopene is one of the compounds in raw and processed Tomato Products that may contribute to a lower risk of prostate cancer; however, this hypothesis remains to be further investigated. Other carotenoids and phytochemicals in Tomato Products may also contribute to the proposed health benefits. Food processing does not seem to reduce the benefits but may, in fact, enhance the bioavailability of beneficial components. The reported correlations or associations between the consumption of Tomato Products and prostate cancer risk should not be interpreted as causal until additional data are available from a variety of studies in different populations. Ideally, randomized controlled intervention studies would provide an ultimate test of the Tomato/lycopene hypothesis; however, the expense, long duration of exposure, and the near universal consumption of Tomato Products among Americans make a dietary intervention study difficult to undertake. It is reasonable to recommend to the general population the consumption of Tomato Products at approximately one serving per day or five servings per week as part of an overall healthy dietary pattern that may reduce the risks of prostate cancer, other malignancies, or other chronic diseases. This recommendation is consistent with current dietary guidelines to increase fruit and vegetable consumption to lower the risk of heart disease and many types of cancer [38]. Nutritional prevention of prostate cancer is very different from the use of dietary or nutritional treatments for established prostate cancer. The use of lycopene and other extracts for the treatment of prostate cancer is a separate issue that warrants individual attention and investigation.

  • lycopene Tomato Products and prostate cancer prevention have we established causality
    Pure and Applied Chemistry, 2002
    Co-Authors: Elizabeth C Miller, John W Erdman, Craig W Hadley, Thomas W M Boileau, Steven K Clinton
    Abstract:

    The relationship between Tomato Products and prostate cancer prevention has been the subject of increasingly intense research activity over the past decade. The hypothesis that Tomato Products contain phytochemicals, perhaps lycopene and others, that modify prostate carcinogenesis warrants investigation. However, scientists, regulatory agencies, marketers of Products, and those defining public health policy have differing opinions regarding the strength of the data when applied to criteria for inference and causality. It is useful to briefly review these criteria and discuss the relative strengths and weaknesses of the published data in order to better define future directions for research. Accepted categories of criteria include: consistency, strength of association, biological gradient, temporality, specificity, biological mechanisms and coherence, and experimental evidence. We believe that continued support for research regarding Tomato Products, lycopene and other phytochemicals, and prostate cancer risk is warranted and may ultimately serve as the basis for more consistent public health recommendations for the consumer. But, what do we say to the public when the data is still inconclusive? The authors support the recommendation that a minimum of five serv- ings of fruit and vegetables should be consumed daily from a variety of sources. We believe that the hypothesized benefits of Tomato Products for prostate cancer prevention may be achieved with approximately five servings of Tomato Products per week. The consumption of lycopene supplements is not currently recommended for prostate cancer prevention or ther- apy. Future research will allow us to provide more definitive guidelines.

Kati Frohlich - One of the best experts on this subject based on the ideXlab platform.

  • Lack of effects of Tomato Products on endothelial function in human subjects: results of a randomised, placebo-controlled cross-over study.
    British Journal of Nutrition, 2010
    Co-Authors: Verena Stangl, Claudia Kuhn, Sonja Hentschel, Nicoline Jochmann, Christine Jacob, Christine Gericke, Volker Böhm, Lars Muller, Kati Frohlich, Mario Lorenz
    Abstract:

    Epidemiological studies suggest that consumption of Tomato Products reduces the risk of CVD via antioxidant, hypocholesterolaemic and anti-inflammatory mechanisms. Although experimental data also describe beneficial effects on endothelial function, clinical data in human subjects are lacking. To test the hypothesis that Tomato ingestion ameliorates endothelial function, we randomised healthy non-smoking postmenopausal women to consume a buttered roll with and without Tomato puree (70 g) in a cross-over design. Endothelial-dependent flow-mediated dilation (FMD) and endothelial-independent nitro-mediated dilation of the brachial artery were assessed with high-resolution ultrasound (13 MHz linear array transducer). Acute (24 h) and long-term (7 d) effects were examined after daily consumption of the described meal. Nineteen volunteers completed the protocol and provided technically suitable ultrasound measurement data. Plasma lycopene levels increased from 0·30 ( sem 0·04) (baseline) to 0·42 ( sem 0·04) and to 0·74 ( sem 0·06) μ m after 24 h and 7 d, respectively, with Tomato puree consumption. These data indicated an effective absorption of the Tomato product. However, both acute and long-term Tomato puree consumption had no effects on endothelium-dependent or -independent dilation of the brachial artery. In addition, we found no correlation between lycopene plasma levels and FMD. In conclusion, consumption of Tomato Products associated with a significant increase in plasma lycopene levels had no effects on endothelial function in healthy postmenopausal women.

  • effects of ingestion of Tomatoes Tomato juice and Tomato puree on contents of lycopene isomers tocopherols and ascorbic acid in human plasma as well as on lycopene isomer pattern
    British Journal of Nutrition, 2006
    Co-Authors: Kati Frohlich, Karin Kaufmann, R Bitsch, Volker Böhm
    Abstract:

    Tomatoes are an important part of the diet. Lycopene, the predominant carotenoid in Tomatoes, is hypothesised to mainly mediate the health ben-efits of Tomato Products. Anticancer activity of Tomato Products and lycopene has been suggested by numerous studies. The aim of the presentstudy was to investigate the effect of ingestion of three different Tomato-based foodstuffs on plasma contents of lycopene, tocopherols and ascorbicacid. Because isomers of lycopene may have different biological activities, a special interest was to look how the lycopene isomer pattern is chan-ged depending on the matrix of Tomato Products. Following a 2-week depletion phase volunteers ingested 12·5mg lycopene/d for 4 weeks com-prising Tomatoes, Tomato juice or Tomato pure´e. The basal levels of lycopene in plasma were comparable for all groups and decreased significantlyduring the 2 weeks of depletion to approximately half of the basal values. Following intervention, plasma lycopene concentration increased sig-nificantly. Conversely, supplementation did not significantly affect levels of tocopherols and ascorbic acid in plasma. Regarding isomers of lyco-pene, the (Z)-lycopene:(all-E)-lycopene plasma isomer ratio was significantly changed during the study for all groups. A remarkable enrichment ofthe relative contents of (5Z)-lycopene was observed during the depletion period, which supports the hypothesis that lycopene (Z)-isomers areformed within the human body after ingestion of (all-E)-lycopene. After dietary intervention with lycopene-rich Products the isomer ratios returnedto those observed at the start of the study. Further investigations will clarify the process of isomerisation in more detail.Tomato Products: (all-E)-Lycopene: Lycopene (Z)-isomers: Ascorbic acid: Tocopherols: Human bioavailability

  • effects of ingestion of Tomatoes Tomato juice and Tomato puree on contents of lycopene isomers tocopherols and ascorbic acid in human plasma as well as on lycopene isomer pattern
    British Journal of Nutrition, 2006
    Co-Authors: Kati Frohlich, Karin Kaufmann, R Bitsch, Volker Böhm
    Abstract:

    Tomatoes are an important part of the diet. Lycopene, the predominant carotenoid in Tomatoes, is hypothesised to mainly mediate the health benefits of Tomato Products. Anticancer activity of Tomato Products and lycopene has been suggested by numerous studies. The aim of the present study was to investigate the effect of ingestion of three different Tomato-based foodstuffs on plasma contents of lycopene, tocopherols and ascorbic acid. Because isomers of lycopene may have different biological activities, a special interest was to look how the lycopene isomer pattern is changed depending on the matrix of Tomato Products. Following a 2-week depletion phase volunteers ingested 12.5 mg lycopene/d for 4 weeks comprising Tomatoes, Tomato juice or Tomato puree. The basal levels of lycopene in plasma were comparable for all groups and decreased significantly during the 2 weeks of depletion to approximately half of the basal values. Following intervention, plasma lycopene concentration increased significantly. Conversely, supplementation did not significantly affect levels of tocopherols and ascorbic acid in plasma. Regarding isomers of lycopene, the (Z)-lycopene:(all-E)-lycopene plasma isomer ratio was significantly changed during the study for all groups. A remarkable enrichment of the relative contents of (5Z)-lycopene was observed during the depletion period, which supports the hypothesis that lycopene (Z)-isomers are formed within the human body after ingestion of (all-E)-lycopene. After dietary intervention with lycopene-rich Products the isomer ratios returned to those observed at the start of the study. Further investigations will clarify the process of isomerisation in more detail.

Sanjiv Agarwal - One of the best experts on this subject based on the ideXlab platform.

  • Tomato lycopene and its role in human health and chronic diseases
    Canadian Medical Association Journal, 2004
    Co-Authors: Sanjiv Agarwal, Akkinappally Venketeshwer Rao
    Abstract:

    LYCOPENE IS A CAROTENOID THAT IS PRESENT IN TomatoES, processed Tomato Products and other fruits. It is one of the most potent antioxidants among dietary carotenoids. Dietary intake of Tomatoes and Tomato Products containing lycopene has been shown to be associated with a decreased risk of chronic diseases, such as cancer and cardiovascular disease. Serum and tissue lycopene levels have been found to be inversely related to the incidence of several types of cancer, including breast cancer and prostate cancer. Although the antioxidant properties of lycopene are thought to be primarily responsible for its beneficial effects, evidence is accumulating to suggest that other mechanisms may also be involved. In this article we outline the possible mechanisms of action of lycopene and review the current understanding of its role in human health and disease prevention.

  • lycopene content of Tomato Products its stability bioavailability and in vivo antioxidant properties
    Journal of Medicinal Food, 2001
    Co-Authors: Anita Agarwal, Sanjiv Agarwal, Honglei Shen, Ashok Rao
    Abstract:

    Lycopene is a bioactive carotenoid present in many fruits and vegetables. Tomatoes constitute the major dietary source of lycopene. Recent evidence shows lycopene to be associated with several health benefits. However, very little information is available about the stability of lycopene and its bioavailability. Because Tomatoes undergo extensive processing and storage before consumption, a study was conducted to evaluate the stability, isomeric form, bioavailability, and in vivo antioxidant properties of lycopene. Total lycopene and isomers were measured by spectrophotometry and high-performance liquid chromatography, respectively. Lycopene content of Tomatoes remained unchanged during the multistep processing operations for the production of juice or paste and remained stable for up to 12 months of storage at ambient temperature. Moreover, subjecting Tomato juice to cooking temperatures in the presence of corn oil resulted in the formation of the cis isomeric form, which was considered to be more bioavailable. Lycopene was absorbed readily from the dietary sources. Serum lipid and low-density lipoprotein oxidation were significantly reduced after the consumption of Tomato Products containing lycopene.

  • role of antioxidant lycopene in cancer and heart disease
    Journal of The American College of Nutrition, 2000
    Co-Authors: Venket A Rao, Sanjiv Agarwal
    Abstract:

    Lycopene, a carotenoid without provitamin-A activity, is present in many fruits and vegetables; however, Tomatoes and processed Tomato Products constitute the major source of lycopene in North American diet. Among the carotenoids, lycopene is a major component found in the serum and other tissues. Dietary intakes of Tomatoes and Tomato Products containing lycopene have been shown to be associated with decreased risk of chronic diseases such as cancer and cardiovascular diseases in several recent studies. Serum and tissue lycopene levels have also been inversely related with the chronic disease risk. Although the antioxidant properties of lycopene are thought to be primarily responsible for its beneficial properties, evidence is accumulating to suggest other mechanisms such as modulation of intercellular gap junction communication, hormonal and immune system and metabolic pathways may also be involved. This review summarizes the background information about lycopene and presents the most current knowledge with respect to its role in human health and disease.

  • Lycopene content of Tomatoes and Tomato Products and their contribution to dietary lycopene
    Food Research International, 1998
    Co-Authors: A.v. Rao, Zeeshan Waseem, Sanjiv Agarwal
    Abstract:

    Abstract Tomatoes are an integral part of diet world wide. Many population studies have established link between dietary intake of Tomatoes, a major source of a carotenoid antioxidant lycopene and reduced risk of chronic diseases. This study evaluates the lycopene contents of various commonly consumed Tomato Products and estimates its daily intake levels. A fast and simple spectrophotometric method for routine analysis of lycopene was developed and validated against HPLC method. Lycopene content in various Tomato Products ranged from 42 ppm to 365 ppm. Average daily dietary lycopene intake levels were assessed by administering food frequency questionnaire and were estimated to be 25.2 mg day−1. Fresh Tomatoes accounted for 50% of total lycopene intake.

  • bioavailability and in vivo antioxidant properties of lycopene from Tomato Products and their possible role in the prevention of cancer
    Nutrition and Cancer, 1998
    Co-Authors: A.v. Rao, Sanjiv Agarwal
    Abstract:

    Oxidative stress is recognized as one of the major contributors of increased risk of cancer. Many recent population studies have established a close link between dietary intake of Tomatoes, a major source of the carotenoid antioxidant lycopene, and lowered risk of cancer. A study was conducted on 19 healthy human subjects to evaluate the uptake and in vivo antioxidant properties of lycopene, using a randomized, crossover design. Dietary lycopene was provided by Tomato juice, spaghetti sauce, and Tomato oleoresin for a period of one week each. Blood samples were collected at the end of each treatment. Serum lycopene was extracted and measured by high-performance liquid chromatography using an absorbance detector. Serum thiobarbituric acid-reactive substances, protein thiols, and 8-oxodeoxyguanosine contents of lymphocyte DNA were assayed to measure lipid, protein, and DNA oxidation. Lycopene was the major carotenoid present in the serum. Dietary supplementation of lycopene resulted in a significant increase in serum lycopene level and diminished amounts of serum thiobarbituric acid-reactive substances. Although not statistically significant, a tendency of lowered protein and DNA oxidation was observed. There was also indication that the lycopene levels increased in a dose-dependent manner in the case of spaghetti sauce and Tomato oleoresin. These results indicate that lycopene is readily absorbed from Tomato Products and may act as an in vivo antioxidant. It may, therefore, play an important role in the prevention of cancer.