To specify the genotypic variation of Mediterranean Citrus juices, the contents of carotenoids, flavonoids, and vitamin C were determined by high-performance liquid chromatography. A selection of ...orange varieties and Mandarin species from the Mediterranean area (Citrus sinensis, Citrus deliciosa Ten, and Citrus clementina Hort. ex Tan) was evaluated using carotenoid profiles and flavanones contents. Among the eight varieties of orange (Salustiana, Hamlin, Shamouti, Pera, Valencia, Maltaise, Sanguinelli, and Cara-cara) and two Mandarin species, only three cultivars (Pera, Sanguinelli, and Shamouti) and the two Mandarin species displayed a high content of vitamin A (374, 381, and 272 ER L-1 for the three orange cultivars and 1156 and 960 retinol equivalent (RE) L-1 for the Mandarins) due to a high content of β-cryptoxanthin. These same Citrus were also rich in hesperidin (502, 537, 552, 767, and 754 mg L-1, respectively). Principal component analysis allowed the Mediterranean orange varieties and Mandarin species to be differentiated on the basis of nutritional criteria. Strong correlations were observed between β-cryptoxanthin and hesperidin (r = 0.92) and between β-cryptoxanthin and β-carotene (r = 0.98). In contrast, vitamin C content was not correlated with carotenoids and flavanone glycosides. The Mandarin and orange group was quite distinct. The orange varieties could be divided in two groups. In addition, a diversity tree allowed a genetic approach to differentiating Citrus cultivars on the basis of Euclidian distances. This representation showed that the hybrid Clementine was nearer to its parent Mandarin than to its parent orange, suggesting that β-cryptoxanthin was a dominant genetic factor. With regard to vitamin A, Mandarin and its hybrid Clementine appeared to be the best Citrus species. Keywords: Citrus sinensis; Citrus reticulata; Mediterranean Citrus; micronutrients; carotenoid; hesperidin; vitamin C; β-cryptoxanthin; orange juice, varietal selection
Épidémiologie.
L’obésité et les maladies chroniques représentent des problèmes de santé majeurs dans les Antilles françaises où une grande partie de la population est précaire. Pourtant, les ...inégalités socioéconomiques des maladies chroniques y sont peu explorées et la contribution de la qualité de l’alimentation pouvant expliquer ces inégalités n’a jamais été évaluée. Nous avons donc étudié les associations entre les indicateurs de statut socioéconomique et la prévalence du syndrome métabolique (MetS) dans les Antilles Françaises et l’effet médiateur de la qualité de l’alimentation.
Les apports alimentaires ont été estimés par des rappels de 24h chez 1144 participants (≥16 ans) inclus dans l’étude Kannari, enquête à visée représentative de la population générale résidant en Guadeloupe et Martinique. La qualité de l’alimentation a été évaluée par le « Diet Quality Index-International » (DQI-I) de 0 à 100 points. La prévalence du MetS a été estimée selon les critères du Joint Interim Statement, à partir de mesures biologiques et anthropométriques. Les associations entre les indicateurs de position socioéconomique (niveau d’éducation, être allocataire d’une aide sociale, situation par rapport à l’emploi, foyer avec enfants, famille monoparentale) et la prévalence du MetS, ainsi que l’effet médiateur de la qualité de l’alimentation ont été évalués grâce à des régressions logistiques multivariables, ajustées sur le département (Guadeloupe ou Martinique), le sexe, l’âge et l’indice de masse corporelle.
Les prévalences du MetS chez les Guadeloupéens et les Martiniquais étaient de 18 % et 28 % respectivement. Les participants ayant un niveau d’éducation primaire ou secondaire (ORprimairevs.≥bac = 1,9 ; IC 95 %=1,0–3,6 et ORsecondairevs.≥bac=2,7 ; IC 95 %=1,4–5,1) et les allocataires d’une aide sociale (OR=2,2 ; IC 95 %=1,1–4,2) présentaient un risque plus élevé de MetS comparés aux participants de niveau d’éducation supérieur et aux non-allocataires. La qualité de l’alimentation expliquait 11 % de la variation du risque de MetS dû au niveau d’éducation et seulement 2 % de la variation dû au fait d’être allocataire d’aide sociale.
La qualité de l’alimentation contribue peu à expliquer les inégalités socioéconomiques du MetS observées en Guadeloupe et Martinique. L’étude de l’influence d’autres facteurs du mode de vie (tabagisme, alcool, activité physique) est nécessaire pour mieux comprendre les mécanismes des inégalités socioéconomiques de santé et ainsi guider les actions de santé publique futures.
The present study aims first to compare the antioxidant microconstituent contents between organically and conventionally grown tomatoes and, second, to evaluate whether the consumption of purees made ...of these tomatoes can differently affect the plasma levels of antioxidant microconstituents in humans. When results were expressed as fresh matter, organic tomatoes had higher vitamin C, carotenoids, and polyphenol contents (except for chlorogenic acid) than conventional tomatoes. When results were expressed as dry matter, no significant difference was found for lycopene and naringenin. In tomato purees, no difference in carotenoid content was found between the two modes of culture, whereas the concentrations of vitamin C and polyphenols remained higher in purees made out of organic tomatoes. For the nutritional intervention, no significant difference (after 3 weeks of consumption of 96 g/day of tomato puree) was found between the two purees with regard to their ability to affect the plasma levels of the two major antioxidants, vitamin C and lycopene. Keywords: Organic cultural practices; tomatoes (Lycopersicon esculentum); lycopene; β-carotene; vitamin C; polyphenols
The carotenoid lutein is thought to play a role in the human eye and to protect against age-related macular degeneration. Lutein transport in the human intestine has not been characterized. We ...examined lutein transport processes using Caco-2 TC-7 monolayers as a model for human intestinal epithelium. Purified lutein was mixed with phospholipids, lysophospholipids, cholesterol, mono-olein, oleic acid and taurocholate to obtain lutein-rich mixed micelles that mimicked those found under physiological conditions. The micelles were added to the apical side of Caco-2 TC-7 cell monolayers for 30 min or 3 h at 37 degrees C. Absorbed lutein, i.e. the sum of lutein recovered in the scraped cells and in the basolateral chamber, was quantified by HPLC. Transport rate was measured (i) as a function of time (from 15 to 60 min), (ii) as a function of micellar lutein concentration (from 1.5 to 15 microM), (iii) at 4 degrees C, (iv) in the basolateral to apical direction, (v) after trypsin pretreatment, (vi) in the presence of beta-carotene and/or lycopene, (vii) in the presence of increasing concentrations of antibody against SR-BI (scavenger receptor class B type 1) and (viii) in the presence of increasing concentrations of a chemical inhibitor of the selective transfer of lipids mediated by SR-BI, i.e. BLT1 (blocks lipid transport 1). The rate of transport of lutein as a function of time and as a function of concentration was saturable. It was significantly lower at 4 degrees C than at 37 degrees C (approx. 50%), in the basal to apical direction than in the opposite direction (approx. 85%), and after trypsin pretreatment (up to 45%). Co-incubation with beta-carotene, but not lycopene, decreased the lutein absorption rate (approx. 20%) significantly. Anti-SR-BI antibody and BLT1 significantly impaired the absorption rate (approx. 30% and 57% respectively). Overall, these results indicate that lutein absorption is, at least partly, protein-mediated and that some lutein is taken up through SR-BI.
The effects of two dietary proteins on dry matter recovery, trichloroacetic acid (TCA) soluble protein concentration, and peptide distribution in gastrointestinal contents were investigated in rats ...trained to consume, in a single 2-hour daily meal, diets containing α-lactalbumin ( α-LA) or whey protein concentrate (WPC) for two weeks. Compared with the WPC diet, the α-LA diet emptied faster from the stomach. Dry matter recovery was higher in the stomach contents of rats fed the WPC diet than in those given the α-LA diet, but dry matter content in the small intestine was comparable. TCA soluble protein levels in the stomach and the small intestinal contents were also significantly (P < 0.001) higher in rats fed the WPC diet. The concentration of peptides having molecular weights (MW) ranging from 12 50030 000 daltons (Da) was higher in the stomach contents of rats fed the WPC diet. Conversely, the level of peptides ranging from 500012 500 Da was higher in the stomach contents of rats fed the α-LA diet. For both diets, the small intestinal contents were characterized by high levels of amino acids and small peptides. These results suggest that the hydrolysis and absorption of α-LA is faster than that of WPC.Key words: In vivo protein digestion, peptides absorption, whey protein concentrate, α-lactalbumin, stomach emptying.
Celotno besedilo
Dostopno za:
DOBA, FSPLJ, IZUM, KILJ, NUK, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK
Although extreme climatic events may have profound effects on ecological systems, there is a marked lack of information on adaptation to such events. In this study, we employed reciprocal ...transplantation on both a geographic scale (experimental sites 200 km apart in different parts of the range of the study species) and a local landscape scale (reciprocal populations separated by 2—8 km) to study the performance of different chemical forms of Thymus vulgaris which naturally occur in different climatic environments. Survival and growth were analyzed in relation to long-term and contemporary climate data in natural populations and our experimental sites. The reciprocal transplants involved a period of six years for clones transplanted in experimental field sites on a geographic scale and three years for seedlings transplanted among natural populations at the local landscape level. Cloned transplants on a geographic scale produced evidence for local adaptation to either summer drought, primarily following the extreme summer drought of 2003, or severe early-winter freezing. Chemotypes that show high survival after intense summer drought showed poor survival after intense early-winter freezing and vice versa, results which directly accord with climate data for their original sites. On the local landscape scale, we found further evidence for local adaptation to summer drought but not to winter freezing (probably due to the absence of extreme freezing during the three years of this study). Future modifications to the occurrence and frequency of extreme climate events may have a profound influence on the spatial distribution of thyme chemotypes.
The influence of Gamma irradiation on content of some important flavonoïds (flavonones glycosides and polymethoxylated flavones) was evaluated during storage of Moroccan clementina treated at a mean ...dose of 0.3 kGy and stored three months at 3′C. Results shows that at day one, gamma irradiation induced degradation of small quantities of these flavonoïds, however after 14 days of storage, the content of these compounds was significantly higher (p≤0.05) in irradiated samples. Irradiation stimulated biosynthesis of flavonoïds after 14 days of storage. Hesperidin was the major flavanones compounds in clementines. Nobiletin and Heptamethoxyflavone were the major polymethoxylated flavones in clementines. Our study demonstrated that the content of these compounds was significantly higher (p≤0.05) in irradiated samples.
PDF
