La maladie de Kashin-Beck: évaluation des apports quotidiens en minéraux chez les jeunes enfants tibétains des régions endémiques

Kashin-Beck disease is an endemic and chronic osteochondropathy. This disease principally occurs in the Tibet Autonomous Region and in several provinces of the People’s Republic of China. Although many studies have already been conducted and many others are still underway, its ethiology remains unknown. A multifactorial hypothesis has been proposed: selenium deficiency, high concentration of organic matters in drinking water (fulvic acids) and mycotoxin poisoning by fungi infecting cereals. This original study aimed to measure the mineral contents of the food most often consumed in severe endemic regions and then to evaluate the daily intake of minerals in young Tibetan children from endemic areas. The mineral elements were selected in relation to their implications in bone metabolism. A sampling campaign split up into two time periods (winter and spring) was carried out. Ten families from two distinct regions were selected based on three criteria: they live in endemic areas; they include a 3 to 5 year-old child; this child has a KBD brother or sister. At the same time, a nutritional survey was made by the means of a prospective questionnaire in order to list the 24h food intake of the 3 to 5 year-old child. This survey highlighted the extremely monotonous cereal-based Tibetan diet. An analytical method for the minerals was developed as follows: mineralization of samples performed by microwave-assisted wet process; mineralized solutions measured by several atomic absorption or emission spectrometric methods and molecular absorption spectrometric methods. The analytical method was validated by mean of certified reference materials. Mean food contents were calculated and compared to food composition reference tables. High iron contents and selenium deficiencies were highlighted in several foods. Daily intakes were estimated combining mineral measurements and nutritional survey results. These were compared to dietary reference intakes from reference tables. This estimation reveals some crucial points: we confirm a marked deficiency in calcium; Ca/P ratios are always low; iron and copper intakes are excessive; zinc is the most probably deficient; while selenium could be deficient; manganese intakes often exceed toxicity thresholds. Nevertheless, this study encounters some limits. The bioavailability of minerals is a critical point that deserves further investigations. Moreover, a larger study over a longer term covering both endemic and non-endemic regions is required for definite conclusions to be reached.La maladie de Kashin-Beck se traduit par une osteochondropathie endémique et chronique. Cette maladie se rencontre principalement dans la Région Autonome du Tibet et dans plusieurs provinces de la République Populaire de Chine. Bien qu’ayant fait et faisant toujours l’objet de nombreuses études, l’étiologie de cette maladie demeure inconnue. Une hypothèse multifactorielle est cependant formulée impliquant : une carence en sélénium, une forte concentration en acides organiques (notamment acides fulviques) dans l’eau de consommation et un empoisonnement par des mycotoxines dû à une contamination des céréales par des moisissures. Cette étude originale avait pour objet l’analyse des teneurs en minéraux des principaux aliments consommés dans des zones de haute prévalence de la maladie et l’évaluation des apports journaliers en minéraux chez les jeunes enfants susceptibles de déclarer la maladie. Les minéraux étudiés ont été choisis en fonction de leurs implications dans le métabolisme des tissus osseux. Une campagne de prélèvement répartie sur deux périodes (hiver et printemps) a été organisée. Un échantillonnage de 10 familles réparties dans deux régions a été réalisé selon trois critères de sélection : les régions devaient être endémiques ; la famille devait comprendre un enfant âgé de trois à cinq ans ; cet enfant devait avoir un frère ou une soeur atteint de la maladie. Parallèlement à cela, une enquête nutritionnelle a été menée au moyen d’un questionnaire alimentaire prospectif dans le but d’établir la consommation alimentaire sur 24h de l’enfant âgé de trois à cinq ans. Cette étude met en évidence le caractère très monotone de l’alimentation tibétaine, essentiellement basée sur les produits céréaliers. La méthode analytique de dosage des éléments fut la suivante : les échantillons ont subi une minéralisation par voie humide assistée par micro-ondes ; les solutions minéralisées ont été dosées par plusieurs méthodes spectrométriques d’absorption et d’émission atomique ainsi que d’absorption moléculaire. La méthode analytique (minéralisation + dosage) a été validée par une analyse de matériaux de référence certifiés ayant subi la même procédure. Les teneurs moyenne en éléments des différents aliments ont été calculées et comparée à des tables de composition des aliments. Des teneurs excessives en fer et une carence marquée en sélénium ont été constatées dans plusieurs aliments. Les apports quotidiens ont ensuite été estimés en combinant les résultats des analyses minérales et de l’enquête nutritionnelle. Ceux-ci ont été comparés aux apports alimentaires recommandés provenant de tables de référence. Les résultats de cette étude confirme certaines suppositions émises et suggèrent des pistes intéressantes quant aux carences et excès rencontrés : le déficit en calcium est très nettement marqué ; les rapports Ca/P sont beaucoup trop faibles ; les apports en fer et en cuivre sont excessifs ; une carence en zinc est fort probable tandis que celle en sélénium est vraisemblable; l’ingestion de manganèse dépasse souvent les seuils de toxicités. Néanmoins ce travail présente certaines limites et une étude plus complète permettrait de compléter ces résultats. Notamment une étude abordant la biodisponibilité des minéraux dans l’alimentation tibétaine et portant sur des régions endémiques et non-endémiques serait nécessaire pour arriver à des conclusions plus probantes

Mineral nutrition and micronutrient deficiencies

Les populations occidentales actuelles accordent de plus en plus d’importance à leur alimentation. Mais Il ne s’agit plus seulement d’intérêts organoleptiques ou hédonistes. Les consommateurs d’aujourd’hui sont plus que jamais attentifs au caractère nutritionnel de ce qui se trouve dans leur assiette. Preuve en est le nombre sans cesse croissant d’alicaments et d’allégations nutritionnelles et de santé qui apparaissant sur le marché. Autre exemple, la tendance graduelle de la part des entreprises agro-alimentaires de « décortiquer » un produit en ses différents nutriments essentiels, tels les protéines, les lipides, les sucres ou encore les fibres. Il est aussi de plus en courant d’y associer le pourcentage de l’apport quotidien recommandé contenu dans le produit. De nos jours, même l’importance des vitamines et des minéraux majeurs (Na, Ca, P, etc.) est ancrée dans les mentalités. Il y a cependant une catégorie de nutriments encore quelque peu délaissée : les oligoéléments. Les oligoéléments sont des éléments chimiques présents en très faibles quantités dans l’organisme mais dont le rôle est essentiel. Les plus connus sont l’iode, le fer, le cuivre le zinc ou encore le manganèse. D’autre par contre sont moins connus mais sont tout aussi indispensables (parfois en plus faible quantités encore) comme le molybdène, le nickel, le chrome, le cobalt et beaucoup d’autres. Les rôles de ces éléments sont aussi diverses qu’indispensables et on les retrouves dans des enzymes et cofacteurs (souvent dans le site actif), dans des hormones, mais ils peuvent aussi jouer un rôle structural (exemple du fluor dans l’hydroxyapatite). Parfois il n’y a qu’un pas à franchir entre oligoélément et élément toxique. C’est par exemple le cas de l’aluminium et de l’arsenic, qui sont nécessaires en petites quantités mais peuvent devenir des poisons (mortels) s’ils sont ingérés à plus forte dose

Contribution à l'étude de l'hypothèse minérale en rapport avec la maladie de Kashin-Beck dans la Région autonome du Tibet

A little known disease called Kashin-Beck disease (KBD) plagues the poor and rural populations in the Tibet Autonomous Region (T.A.R.) and in other provinces of the People’s Republic of China. It is an endemic and chronic osteochondropathy affecting long bones and joints, sometimes as soon as of the early childhood. Although the etiology of this disease is not clearly established, little doubt remains as to the implication of multiple environmental factors. Intoxication by mycotoxins in cereals and by organic acids in water, deficiencies in selenium and iodine, are all factors having a place in the multifactorial etiology hypothesized. In T.A.R., diet, notably, differentiates the rural community, affected by KBD, from the other communities (nomads and city-dwellers), who remain unaffected. Because more than one chemical element is essential to a healthy bone metabolism, and because there is scarce data, if not any, on the topic, this thesis had to primary objective to investigate the mineral and trace element dietary status of young Tibetan children living in areas endemic for KBD. The first logical action step led us to determine which elements are involved in bone and joints metabolism through an exhaustive review of the scientific literature. Thirty elements were highlighted, and a dozen was deemed relevant in this context. An exploratory study on the Tibetan food composition concluded on a high risk of introducing important bias by using the existing food composition tables for nutritional assessment in T.A.R. Being inescapable tools, a specific food composition table was elaborated for our area of investigation with the close collaboration of the China National Center for Food Safety Risk Assessment (CFSA). During a scientific internship of 7 month in the CFSA, 19 chemical elements were analyzed in not less than 1119 samples of sixteen traditional foods and beverages of rural T.A.R. In order to assess the nutritional status of the children, a cross-sectional study was implemented. 250 preschool children aged 3 to 5 years old from three rural counties around Lhasa were enrolled. They were interviewed twice, at six month of interval, via the 24-hour recall method. The results suggest several imbalances in their dietary mineral intakes compared to the Chinese recommendations. Sodium and manganese intakes are too high, while they are too low for potassium, calcium, zinc, copper and selenium. The Tibetan diet is rich in fiber and in phytic acid, which are susceptible to decrease the bioavailability and to aggravate the deficiencies of the later elements. For this reason, we conducted an animal experimentation on a rat model to assess the apparent digestibility, the fecal excretion and the urinary excretion of minerals and trace elements in the traditional Tibetan dish called tsampa pag. This traditional dish consisting of roasted barley flour mixed with yak butter tea is the mainstay of the Tibetan diet. The results of this experiment suggest low bone mineral density, a possible secondary copper deficiency, and a possible manganese excess in rats that consumed tsampa pag. In view of the results presented, it would be interesting to compare the mineral intake between children living in endemic areas and in non-endemic areas. It would also be interesting to include more of elements known to affect bone metabolism in future studies.Il sévit au sein des populations rurales de la Région Autonome du Tibet (R.A.T.), mais également dans d’autres provinces de la République Populaire de Chine, une maladie peu connue appelée maladie de Kashin-Beck (MKB). Il s’agit d’une ostéochondropathie endémique et chronique qui affecte principalement les os long et les articulations, parfois dès la petite enfance. Bien que l’étiologie de cette maladie ne soit pas clairement établie, peu de doutes subsistent quant à l’implication de multiples facteurs environnementaux. Les facteurs communément admis sont un empoisonnement par des mycotoxines présentent dans les céréales, une contamination de l’eau de consommation par des acides organiques, et des carences alimentaires, notamment en sélénium et en iode. Dans la R.A.T., l’alimentation est un facteur qui constitue une différence majeure entre les populations rurales, affectées par la maladie, et les habitants des villes et les nomades, qui ne sont guère affectés. Etant donné les nombreux éléments chimiques impliqués dans le métabolisme osseux, et le peu de données scientifiques en rapport avec les apports alimentaires de ces populations, cette thèse avait pour but principal l’étude du statut en minéraux et oligo-éléments des jeunes enfants tibétains vivant dans des régions endémique pour la MKB. La première étape logique fut de déterminer exhaustivement les minéraux impliqués, de façon directe ou indirecte, dans le métabolisme osseux. Trente minéraux furent répertoriés, et une dizaine d’entre eux furent jugé pertinents et considérés dans la suite de l’étude. Une évaluation des tables de composition alimentaires existantes conclut à un risque d’erreur important en cas d’utilisation de ces dernières en R.A.T. Etant un outil indispensable à toute étude nutritionnelle, une table de composition alimentaire spécifique a été élaborée en étroite collaboration avec le China National Center for Food Safety Risk Assessment (CFSA). Durant un séjour scientifique de 7 mois au sein du CFSA, 19 éléments chimiques furent analysés dans seize catégories de produits alimentaires traditionnels collectés, en R.A.T. pour un total de 1119 échantillons. Enfin d’évaluer le statut minéral des enfants tibétains, une étude transversale impliquant 250 enfants âgés de 3 à 5 ans et habitant dans trois comtés ruraux de la préfecture de Lhassa a été mise en œuvre. Des données de consommation alimentaires quantitatives ont été récoltées deux fois pour chaque enfant à six mois d'intervalle par la méthode de rappel de 24 heures. Les résultats mettent en évidence plusieurs déséquilibres alimentaires par rapport aux recommandations chinoises (DRIs). Les apports en sodium et en manganèse sont trop élevés, alors qu'ils sont trop faibles pour le potassium, le calcium, le zinc, le cuivre et le sélénium. De plus, l'alimentation tibétaine étant riche en fibres et en acide phytique, un problème de biodisponibilité est susceptible d’aggraver les déficits d’ingestion mis en évidences pour certains éléments, et éventuellement de causer des carences secondaires. Dans cette optique, une expérimentation a été conduite dans le but d’étudier l’absorption et l’excrétion des minéraux chez des rats nourris avec de la tsampa pag. Ce plat traditionnel composé de farine d’orge grillée mélangée à du thé au beurre de yak étant le pilier de l'alimentation tibétaine. Les résultats de cette expérimentation suggèrent une teneur minérale osseuse faible, une possible carence secondaire en cuivre, et un possible excès en manganèse chez les rats ayant consommé la tsampa pag. Au vu des conclusions présentées, il serait intéressant de comparer les apports minéraux entre les enfants vivant en zones endémiques et ceux vivant en zones non endémiques. Il serait également intéressant d’intégrer d’avantages d'éléments connus pour avoir un impact sur le métabolisme osseux dans de futures études

Extraction by three processes of arabinoxylans from wheat bran and characterization of the fractions obtained

Arabinoxylans (AXs) were extracted from destarched wheat bran (DWB) according to different processes, with a view to their production at industrial scale. Two fractions (F3a and F3b, respectively purified on 10 kDa and 100 kDa ultrafiltration membranes) were obtained with low yields by treating DWB with an endoxylanase and this process left a solid residue exhausted in enzyme-extractable AXs (EDWB). F1 and F2 AX fractions were obtained by treatment with sodium hydroxide of respectively DWB and EDWB. The fraction F4 resulted from a hydrothermal treatment of EDWB in a pressure reactor, followed by ethanol precipitation. The different AX fractions were characterized and compared for the composition in monosaccharides, for the contents in fats and in ferulic, phytic and uronic acids, for the molecular mass distribution and the degrees of methylation and acetylation. The alkaline extractions gave one desesterified AX population with molecular mass (MM) higher than 670 kDa and arabinose/xylose ratios (Ara/Xyl) around 1. The enzyme and thermal treatments yielded AXs with two main populations in size-exclusion chromatography (the largest one at 5-12.5 kDa and a second one at 140-160 kDa), having overall Ara/Xyl of respectively 0.7 and 0.5 for both processes. These data bring information about the influence of the process on the characteristics of AX fractions obtained from pretreated wheat bran. Here are also reported processes that enabled to recover enzyme-unextractable AXs from DWB, including an original and up-scalable hydrothermal extraction. Phytate contents of isolated AXs are described for the first time.BARCELONE (474 SPW 6511

Effect of low thermal pasteurization in combination with carvacrol on color, antioxidant capacity, phenolic and vitamin C contents of fruit juices

Mild thermal treatment in combination with natural antimicrobials has been described as an alternative to conventional pasteurization to ensure fruit juices safety. However, to the best of our knowledge, no study has been undertaken to evaluate what could be its effect on their color and nutritional value. This study therefore aimed at assessing how a low thermal pasteurization in combination with carvacrol could affect these parameters, with orange, pineapple, and watermelon juices as selected fruit juices. The experimental design used had levels ranging from 50 to 90°C, 0 to 60 μl/L, and 0 to 40 min for temperature, concentration of carvacrol supplemented, and treatment length, respectively. The only supplementation of fruit juices with carvacrol did not affect their color. In comparison with high thermal pasteurization (>70°C), a combined treatment at mild temperatures (50-70°C) better preserved their color, antioxidant capacity (AOC), and vitamin C content, and increased their total phenolic content (TPC). Globally, carvacrol supplementation had a positive impact on the TPC of thermally treated juices and increased the AOC of treated watermelon juice, which was the lowest of the three fruit juices. Mild heat treatment in combination with natural antimicrobials like carvacrol is therefore an alternative to limit the negative effects of conventional pasteurization on fruit juices quality. © 2018 Published by Wiley Periodicals, Inc

Comparaison de l'apport minéral entre les enfants des zones endémiques et non endémiques pour la maladie de Kashin-Beck en Région autonome du Tibet: étude Pilote

Background The Kashin-Beck disease (KBD) is an endemic and chronic osteochondropathy affecting between 0.74 million and 2.5 million people in the Tibet Autonomous Region and in several provinces of the People’s Republic of China. The etiology remains unclear, although a multifactorial hypothesis has been proposed (selenium/iodine deficiency; high concentration of organic matters in drinking water; and mycotoxin poisoning by fungi infecting cereals). The rural population is almost exclusively affected. Objectives The first objective of this study was to assess and to compare the mineral daily intake between Tibetan preschool children living in endemic areas for the Kashin-Beck disease and those living in non-endemic areas. A second objective was the comparison of children daily intakes with Chinese Dietary Reference Intakes (DRIs). The third objective was to estimate a sample size for a cross-sectional survey aiming to highlight significant differences in mineral intakes between the two groups of preschool children. Materials and Methods Ten Tibetan preschool children were enrolled per group (endemic/non-endemic) for this pilot study. Children had to be weaned and those living in endemic area must have a KBD sibling. The nutrition survey consisted in an interactive simplified 24-hour recall questionnaire. Two 24-hour recalls were recorded for the endemic group, in February 2010 (EAw) and in May 2010 (EAs), while one day has been recorded for the non-endemic group in July 2011 (NEA). At the same time, samples of the main staple foods were collected for chemical analysis. The daily intakes of Ca, P, Mg, Fe, Zn, Cu, and Mn were calculated based on the 24-hour recall records, the chemical analyses, and data from food composition tables (FCTs). Results and discussion We are aware of limitations in the methodological approach of this pilot-study. The number of children, although weak, was empirically decided for the sake of feasibility and because no prior information was available. The interactive 24-hour recalls between the two groups are spaced in time. Nevertheless, the diet of rural Tibetans is far from diversified, and the variability among seasons and years is probably low. Daily intakes in Ca, P, Mg, Fe, Zn, Cu and Mn were calculated for children of each group. Parametric test were applied for comparison of mean daily intakes between groups. A significant difference was highlighted for Cu (p-value<0.01) and Fe (p-value<0.05), no other significant difference was detected. When comparing individual daily intakes and Chinese DRIs, the most striking results concern Ca and Mn. The great majority of children showed severe deficiency in calcium and enormous excess in manganese. A power (1-β) of 80% is commonly accepted when estimating a sample size for a cross-sectional survey. In this case, the maximum sample size is too high and not feasible in practice (several hundred children per group). Oppositely, the power was calculated per mineral, based on 100 children per group. The power is higher than 90% for Mg, Fe, and Cu. For the others minerals, the power is well below 80%. Nevertheless, general deficiencies and excesses have been observed in the two groups for part of these minerals. We believe that it is a statement in itself and trying to highlight small differences between groups in such extremes is not relevant

La maladie de Kashin-Beck: évaluation des apports quotidiens en minéraux chez les jeunes enfants tibétains des régions endémiques

Kashin-Beck disease is an endemic and chronic osteochondropathy. This disease principally occurs in the Tibet Autonomous Region and in several provinces of the People’s Republic of China. Although many studies have already been conducted and many others are still underway, its ethiology remains unknown. A multifactorial hypothesis has been proposed: selenium deficiency, high concentration of organic matters in drinking water (fulvic acids) and mycotoxin poisoning by fungi infecting cereals. This original study aimed to measure the mineral contents of the food most often consumed in severe endemic regions and then to evaluate the daily intake of minerals in young Tibetan children from endemic areas. The mineral elements were selected in relation to their implications in bone metabolism. A sampling campaign split up into two time periods (winter and spring) was carried out. Ten families from two distinct regions were selected based on three criteria: they live in endemic areas; they include a 3 to 5 year-old child; this child has a KBD brother or sister. At the same time, a nutritional survey was made by the means of a prospective questionnaire in order to list the 24h food intake of the 3 to 5 year-old child. This survey highlighted the extremely monotonous cereal-based Tibetan diet. An analytical method for the minerals was developed as follows: mineralization of samples performed by microwave-assisted wet process; mineralized solutions measured by several atomic absorption or emission spectrometric methods and molecular absorption spectrometric methods. The analytical method was validated by mean of certified reference materials. Mean food contents were calculated and compared to food composition reference tables. High iron contents and selenium deficiencies were highlighted in several foods. Daily intakes were estimated combining mineral measurements and nutritional survey results. These were compared to dietary reference intakes from reference tables. This estimation reveals some crucial points: we confirm a marked deficiency in calcium; Ca/P ratios are always low; iron and copper intakes are excessive; zinc is the most probably deficient; while selenium could be deficient; manganese intakes often exceed toxicity thresholds. Nevertheless, this study encounters some limits. The bioavailability of minerals is a critical point that deserves further investigations. Moreover, a larger study over a longer term covering both endemic and non-endemic regions is required for definite conclusions to be reached

The relevance of food composition data for nutrition surveys in rural Tibet: pilot study in the context of Kashin-Beck Disease

Kashin-Beck disease (KBD) is an endemic and chronic osteochondropathy. This disease principally occurs in the Tibet Autonomous Region and in several provinces of the People’s Republic of China. The etiology of the disease remains obscure although environmental factors are assumed to be involved. Diet, in particular, differentiates the rural community, affected by KBD, from the other communities (nomads and city-dwellers), who remain unaffected. In anticipation of a nutrition survey, this study aimed to measure the mineral content (Ca, P, Mg, Fe, Zn, Mn, Cu, Ni, Se, Al, Sr, Mo, Cd, As, Pb, Hg, Cr, and Co) of eight Tibetan staple foods and to compare the results against two food composition tables (FCTs). Foods were sampled in twenty households selected from both an endemic and a non-endemic area of rural Tibet. Ten minerals involved in bone metabolism were measured using atomic and molecular spectrometric methods. Results revealed that a very limited number of food/constituent pairs showed a variation in mineral composition during a single year of testing for a given region. In addition, results showed significant differences in mineral content between the endemic and the non-endemic area, especially for wheat flour. Following our analysis of the mineral content of the Tibetan food samples, results were statistically compared with similar foods listed in two food composition tables: the USDA National Nutrient Database (USDA Food Search for Windows, Version 1.0, database version SR23), and the China Food Composition Table (book 1, 2nd edition). More than 50 to 60% of p-values < 0.05 were highlighted, suggesting the inappropriateness of using FCTs as a reference for nutrition surveys in rural Tibet, and emphasizing the need for analysis of traditional foods. Differences were found to be more or less marked depending on the element considered, and calcium content seemed to show the greatest difference. Although it is obviously too early for definite conclusions to be reached (insufficient number of samples by food and insufficient number of foods analyzed), it seems that the present pilot-study indicates significant discrepancies between measured and tabulated values of the mineral content of certain foods. A more complete survey would therefore seem mandatory

Plant and fish production performance, nutrient mass balances, energy and water use of the PAFF Box, a small-scale aquaponic system

Aquaponics is an integrated farming concept that combines fish and hydroponic plant production in a recirculating water system. This food production system promises a reduced environmental footprint when compared to conventional farming systems. However, questions regarding its sustainability remain and there is a lack of data on its performance. A small-scale aquaponic system named PAFF Box (Plant And Fish Farming Box) consisting of a ship container topped by a greenhouse was studied. Plant yield in ebb-and-flow and deep water culture (DWC) hydroponic beds, lettuce, basil and tilapia production capacity and water and energy consumption were investigated. Additionally, all macro- and micronutrient mass balances were analyzed in order to give a better picture of their dynamics and recycling ability. Thanks to the daily inputs of tap water, and 42g of feed per m2 of plant beds, DWC beds showed 3 to 10 fold higher plant yields than ebb and flow. The production of 1kg of vegetable in DWC consumed 244L of water and 84.5kWh of electricity and 1kg increase of tilapia consumed 278L and 96.2kWh. The system was very efficient in water use for fish production but alternative solutions for warming the water and fine-tuned pumping setup are required to decrease energy needs. Key nutrients such as potassium, phosphorus, iron, copper, zinc, manganese and molybdenum, remained low in solution. Nitrate, calcium, boron and sodium concentrations increased quickly and only water exchange could control their accumulation meanwhile a low daily water exchange rate of 3.6\% implicated a high nutrient loss in the environment. In the willingness to decrease aquaponics environmental footprint, this study indicates that improved designs could be explored such as decoupled aquaponic systems