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Development of Vegetables with Improved Health-Promoting Qualities. Elizabeth Jeffery Department of Food Science and Human Nutrition, University of Illinois. Fruits, Vegetables & Cancer Prevention: Epidemiology is undecided. Variety or Category. % Positive. Vegetables. 80% (59/74). Fruits.
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Development of Vegetables with Improved Health-Promoting Qualities Elizabeth Jeffery Department of Food Science and Human Nutrition, University of Illinois
Fruits, Vegetables & Cancer Prevention:Epidemiology is undecided Variety or Category % Positive Vegetables 80% (59/74) Fruits 64% (36/56) Raw vegetables 87% (40/46) Cruciferous Vegetables 69% (38/55) Allium Vegetables 77% (27/35) Green vegetables 77% (68/88) Carrots 81% (59/73) Tomatoes 71% (36/51) Citrus Fruit 66% (27/41) • The 1997 World Cancer Research Fund and the American Institute for Cancer Research (WCRF/AICR) report: • Food, Nutrition and the Prevention of Cancer: a global perspective, p442. by John D Potter and other panel members
Epidemiology of Dietary Cancer Prevention : Fruit and Vegetables Case-Control Studies Cohort Studies Riboli and Norat, 2003
Food Variability: environment, genotype Human Variability: environment, genotype SAFE EFFECTIVE DOSE BFC i.d. Formulation/ food preparation Bioavailability Biomarkers
Nutrigenomics Post-genomics metabolomics proteomics Nutrigenetics Transcriptomics Epigenetics DNA RNA Protein Metabolites PHENOTYPE Human Variability
Human Variability Crucifers Lower Risk for Lung Cancer More Effectively in those at high risk Relative risk Crucifers/ non-smokers 0.70 (ns) Crucifers/smokers0.31 (p<0.05) Zhao et al, 2001, Cancer Epi Bio Prev 10:1063-7
Breast Cancer Risk, Dietary Crucifers and the GSTT1 Null Phenotype Human Variability OR, Breast Cancer Quartile of Crucifer Intake Fowke et al., Cancer Res. 63: 3980-3986, 2003
2005 and 2003 USDA Nutritional Data for RAW BROCCOLI (abridged): Mean value per 100.00 grams edible part Name Unit Amount Amount #data S.E. 2003 2005 points Food energy kcal: 28.00 28.00 1 Protein g : 2.98 2.98 22 .11 Total lipid (fat) g : 0.35 0.35 22 .03 Carbohydrate g : 5.24 5.24 1 Total saturated fat g : 0.05 0.05 1 Cholesterol mg : 0 0 1 Total dietary fiber g : 3.0 - Vitamin A IU : 1542 3000 1 Ascorbic acid mg : 93.2 93.2 15 2
Carotenoid content of Broccoli Lutein Beta-carotene 10-fold difference Means, 22 different broccoli genotypes (mmol/100g DW)
Glucosinolates: precursors to active components in cruciferous vegetables glucoraphanin
Glucosinolates break down to ITC when plants are crushed or chewed Glucoraphanin Myrosinase ITC Isothiocyanate Anticarcinogen Sulforaphane
VARIATION IN CONTENT: • Determination of scientific basis for variation • CONTROL • Examples (taken from broccoli): • Carotenoids and Tocopherols • Glucosinolates • Sulforaphane production from glucoraphanin
Genotype Genome Metabolome Content of metabolite of interest: Phenotype
Genotype Genome Environment Metabolome Content of metabolite of interest
Genotype Genome Environment Metabolome Processing Content of metabolite of interest in food product
Glucosinolate variation among 50 broccoli varieties; one season
Variation in glucosinolates due to genotype, environment and G x E Indolyl Aliphatic
G1 G2 Metabolite Content E1 E2 Genetics x Environment Interaction G3 G4 Metabolite Content E1 E2
Selective increase of the potential anticarcinogen 4-methylsulphinylbutyl glucosinolate in broccoli. Carcinogenesis. 1998 ;19(4):605-9 • Faulkner K, Mithen R, Williamson G.John Innes Centre, Norwich Research Park, UK.The putative anticarcinogenic activity of Brassica vegetables has been associated with the presence of certain glucosinolates. 4-Methylsulphinylbutyl isothiocyanate (sulphoraphane), derived from the corresponding glucosinolate found in broccoli, has previously been identified as a potent inducer of the anticarcinogenic marker enzyme quinone reductase [NADP(H):quinone-acceptor oxidoreductase] in murine hepatoma Hepa 1c1c7 cells. We have therefore produced a broccoli hybridwith increased levels of this anticarcinogenic glucosinolate and tested the ability of extracts to induce quinone reductase. A 10-fold increase in the level of 4-methylsulphinylbutyl glucosinolate was obtained by crossing broccoli cultivars with selected wild taxa of the Brassica oleracea (chromosome number, n = 9) complex. Tissue from these hybrids exhibited a >100-fold increase in the ability to induce quinone reductase in Hepa 1c1c7 cells over broccoli cultivars, due to both an increase in 4-methylsulphinylbutyl glucosinolate content and increased percentage conversion to sulphoraphane.
Sulforaphane formation: glucoraphanin hydrolysis Glucoraphanin Myrosinase (Crushing) Unstable Intermediate Sulforaphane
Glucoraphanin Hydrolysis Glucoraphanin Myrosinase (Crushing) Unstable Intermediate 85-90% 10-15% Sulforaphane Sulforaphane Nitrile
Defatted Broccoli Seed (1 kg) GC FID Detection GC FID Detection Water Extract Methylene Chloride Extract Preparative HPLC Refractive Index UV 254 nm Sulforaphane (4.8 g) Sulforaphane Nitrile (3.8 g) Matusheski et al, 2001
Induction of QR in Cell Culture1 1Matusheski and Jeffery, 2001
Hepatic QR1 Experiment 1 Experiment 2 * * * *Significantly different from pair fed group (Student’s T-test, p<0.05). Mean ± Standard Error 1Matusheski and Jeffery, 2001
Isothiocyanate Measurements of ESP activity: Epithionitrile:nitrile ratio Sulforaphane: sulforaphane nitrile ratio Nitrile Alkenyl glucosinolates ESP EpithioNitrile Isothiocyanate Non Alkenyl glucosinolates ESP Nitrile ESPmay remove S in glucosinolates that have no receiving alkenyl group
Recombinant Epithiospecifier protein; Effect of Heating Dilution MW Std 100 10 1 200- 116- 97.4- 66- 45- 31-
Broccoli ESP Activity and Bioactivity Bioactivity ESP Activity
ESP activity (epithionitrile: nitrile) correlated with the sulforaphane nitrile: sulforaphane ratio P < 0.05
How can we harness this in processing to optimize sulforaphane ?
Genotype Environment Phenotype processing Stable content of metabolite of interest in food product
Jack Juvik Barbara Klein Mosbah Kushad Matthew Wallig Richard Mithen Malcomb Bennett Anna Keck Allan Brown Anne Kurilich In-Gyu Park Grace Wang Kanta Kobira Nathan Matusheski Ranjan Swarup Acknowledgements