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1.
Summary To determine the extent of mould contamination and the mycoflora of some cereals and cereal products such as barley, corn, rice, wheat,bulgur and flour, a total of 242 samples were collected from different agricultural regions of Turkey. Mould contamination of samples varied between 103 and 106 colonies/g. Moisture contents of the samples were found to range between 12.65 and 13.97%. Most commonly isolated moulds werePenicillium (46%),Aspergillus (22%),Cladosporium (9%),Rhizopus (6%),Aureobasidium (5%) andEurotium (4%) species. Results have been evaluated to assess the kinds of mycotoxins that can be produced by these mycoflora and the effect of seed moisture on growth of the relevant fungi.
Resumen A fin de determinar la extensión de la contaminación por mohos, y la microflora presente en algunos cereales y derivados tales como; avena, maíz, arroz, trigo, bulgar y harina, se recogieron 242 muestras de distintas regiones agrícolas de Turquía. La contaminación por mohos varió entre 103 y 106 colonias/g, y el porcentaje de humedad entre 12.65 y 13.97%. Los mohos que se aislaron con mayor frecuencia fueron especies dePenicillium (46%),Aspergilus (22%),Cladosporium (9%),Rhizopus (6%),Aureobasidium (5%) yEurotium (4%). Los resultados se han evaluado para determinar el tipo de micotoxinas que esta micoflora puede producir y el efecto de la humedad de las semillas en el crecimiento de los hongos más importantes.

Résumé Un total de 242 échantillons a été récolté dans différentes régions agricoles de Turquie, afin de déterminer l'étendue de la contamination par moisissures ainsi que la mycoflore de certaines céréales et produits céréaliers tels l'orge, le maïs, le riz, le froment, le bulgur et la farine. La contamination par moisissures a varié de 103 à 106 colonies par g. L'humidité des échantillons variait entre 12.65 et 13.97%. Les moisissures les plus communément isolées sont lesPencillium (46%), lesAspergillus (22%), lesCladosporium (9%), lesRhizopus (6%), lesAureobasidium (5%) et lesEurotium (4%). Les résultats ont été examinés pour déterminer les types de mycotoxines qui pouvaient être produites par cette mycoflore et l'effet de l'humidité de la graine sur la croissance des moisissures idoines.
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2.
In this study, the levels of aflatoxin B1 (AFB1), ochratoxin A (OTA), zearalenone (ZEN), deoxynivalenol (DON) and fumonisins (FUM) in unprocessed cereals (n = 189) and cereal-based products (n = 61) were determined using validated ELISA methods. All samples originated from either conventional or organic production corresponded to the 2015 harvest in Croatia. Based on the mean mycotoxin concentrations, the risk for the consumer to exceed the tolerable daily intake (TDI) for these toxins by the consumption of both types of cereals and cereal-based products was assessed. Mycotoxin contamination of organic cereals and organic cereal-based products was not significantly different (p > 0.05). Given that the exposure assessment resulted in a small fraction of the TDI (maximum: DON, 12% of TDI), the levels of the investigated mycotoxins in both types of cereals and cereal-based products from the 2015 harvest did not pose a human health hazard.  相似文献   

3.
A Fusarium and Fusarium toxin monitoring programme has been established within the food and feed control authorities of Saxony-Anhalt for the 2001–2003 period. The first results of the deoxynivalenol analyses of cereals and cereal products with assured origin in this federal state, showed a contamination rate of 42% for wheat and wheat products. The contamination incidence reached only 14% in rye and rye products. Zearalenone couldn't be detected at all in the analyzed samples.  相似文献   

4.
Rosanoff  Andrea  Kumssa  Diriba B 《Plant and Soil》2020,457(1-2):5-23
Plant and Soil - The World Health Organisation (WHO) magnesium (Mg) estimated average requirement (EAR) is not adjusted for rise in human body weight (BW) and neglects body Mg stores depletion....  相似文献   

5.
Fusarium culmorum F1 was found to produce and secrete into the culture medium several of 5-n-alkylresorcinols. The amount of resorcinolic lipids was 5.3 microg/g and 0.9 microg/l in mycelium and in post-culture liquid, respectively. First of all F. culmorum F1 produces saturated homologues with C15 to C25 side chains. The extract from the medium contained only homologues with shorter carbon chains (C13 to C17).  相似文献   

6.
A simple statistical procedure has been derived from field experimental data on insecticidal seed coatings for control of wheat bulb fly larvae to measure the direct effect of the insecticides on the yield of wheat.  相似文献   

7.
Androgenesis of wheat, rice and triticale was studied in isolated microspore culture. It is the first publication which studies microspore culture reaction of Hungarian rice varieties. The effect of different basic media, lack and absence of growth regulators in culture media were tested on important parameters of microspore culture. Direct embryogenesis was observed in microspore culture of wheat and triticale genotypes. In the case of rice, calli were induced in isolated rice microspore culture and haploid rice plantlets were regenerated via organogenesis.In wheat, the effect of basic media (W14, A2, CHB3, P4-m) was compared and among them the W14, and A2 had a superior effect on embryo production and albino and green plantlet regeneration. In rice the C, CHB3 and MSm media were tested in microspore culture and the significantly highest numbers of calli were achieved by using C and CHB3 media depending on the genotypes. The lack of exogenous growth regulators was observed in isolated microspore culture of triticale and rice. Growth regulator-free medium had a positive effect on embryo production and plant regeneration of triticale genotypes, whereas in rice microspore culture multicellular structures did not continue their division without growth regulators from the third week of microspore culture. Developing of microspore-origin calli was maintained by supplement of 2,4-D and Kinetin combination in the microspore culture medium.  相似文献   

8.
Kernel hardness is an important agronomic trait that influences end-product properties. In wheat cultivars, this trait is determined by thePuroindoline a (Pina) andPuroindoline b (Pinb) genes, located in theHardness locus (Ha) on chromosome 5DS of the D genome. Wild type alleles code puroindoline a (PINA) and puroindoline b (PINB) proteins, which form a 15-kDa friabilin present on the surface of water-washed starch granules. Both the proteins are accumulated in the starch endosperm cells and aleurone of the mature kernels.Puroindoline-like genes coding puroindoline-like proteins in the starch endosperm occur in some of the genomes of Triticeae and Aveneae cereals. Orthologs are present in barley, rye and oats. However, some genomes of these diploid and polyploid cereals, like that ofTriticum turgidum var.durum (AABB) lack thepuroindoline genes, having a very hard kernel texture. The two wild type alleles in opposition (dominant loci) control the soft pheno-type. Mutation either inPina orPinb or in both leads to a medium-hard or hard kernel texture. The most frequent types ofPin mutations are point mutations within the coding sequence resulting in the substitution of a single amino acid or a null allele. The latter is the result of a frame shift determined by base deletion or insertion or a one-point mutation to the stop codon. The lipid-binding properties of the puroindolines affect not only the dough quality but also the plants’ resistance to pathogens. Genetic modification of cereals withPuroindoline genes and/or their promoters enable more detailed functional analyses and the production of plants with the desired characteristics.  相似文献   

9.
The authors present a new and sensitive method for the determination of T-2- und HT-2 Toxin in cereals and cereal products in the low ppb level. A representative part of the cereal sample is extracted with a mixture of methanol-water (90:10) and the extract is cleaned on the commercially available immunoaffinity column T-2test™ (IAC), eluted with methanol, derivatized by pentafluorpropionic anhydride (PFPA) and measured on a GC-ECD. The method has been successfully validated on wheat, rye and oats. The recovery rates with wheat and rye endowed on a level of 50 ppb and with 85 ppb naturally contaminated oats were 71–115% with a coefficient of variation of 5.7–19.5%. The detection limits of the method with a signal to noise level of 3:1 were 1.5–2.3 μg/kg for HT-2 and 1.1–1.7 μg/kg for T-2 toxin. Financial support: Federal Ministry of Food and Agriculture (part of the project 05HS 001 — Improvement and validation of type A trichothecene (T-2 toxin and HT-2 toxin) analysis and occurrence of these mycotoxins in food marketed in Germany)  相似文献   

10.
Jean Adams discusses the evidence around food marketing restrictions and how they may be an effective way to support public health.

We live in a world increasingly saturated with marketing for less healthy foods [1]. One study found that children in New Zealand see an average of 27 instances of marketing for less healthy foods and only 12 for healthier foods, each day [2]. Food marketing involves activities across the 4 Ps of the marketing mix: product, place, price, and promotion. We are encouraged to buy less healthy food products through their placement in prominent store locations such as checkouts, end of aisles, and store entrances; price discounts; and promotions including advertising, cartoon tie-ins, and celebrity endorsements.Systematic reviews have confirmed the effectiveness of these marketing techniques to influence purchasing and consumption of less healthy foods [35]. Indeed, the documented power of food marketing has led the World Health Organisation to recommended limiting exposure as an overarching and enabling “best buy” to improve diets [6].Supermarkets remain the location of about 70% of food spend in the United Kingdom [7]. The concentration of food marketing in grocery stores can feel particularly overwhelming with parents describing the “temptation” as “like a trip to the zoo every week” for their children [8]. As such, supermarkets may be particularly important venues for addressing food marketing.In 2 accompanying Research Articles in PLOS Medicine, Piernas and colleagues used nonrandomised approaches to study the impacts on sales of a range of strategies to rebalance the marketing of healthier versus less healthy products in 3 large UK supermarket chains [9,10]. Across the 2 papers, 7 different interventions were implemented that changed the relative availability of healthier versus less healthy products (2 interventions), removed less healthy products from prominent positions, placed healthier products at eye level, offered price discounts on healthier products, increased signage on healthier products, and applied a range of entertainment tie-in promotions on healthier products (one intervention each). These variously had the intention to encourage substitution of less healthy products with healthier alternatives or to reduce purchasing of less healthy foods without substitution.Increasing the relative availability of healthier products, removing less healthy products from prominent positions and price promotions on healthier products were all associated with changes in unit sales in the expected direction, although associations with changes in nutrients purchased were sometimes more modest. In contrast, moving healthier products to eye level and increasing signage were not associated with changes in sales. These findings are particularly timely in England where a range of measures to reduce exposure to marketing of less healthy foods in retail environments are due to be implemented from October 2022 [11].Piernas and colleagues worked in collaboration with large UK supermarket chains. That the chains were prepared to innovate to support public health indicates that rebalancing marketing towards healthier products may not be as burdensome to the sector as it has sometimes claimed [12]. It also strengthens the external validity of these studies giving an indication of how customers react in real-world environments.However, that the supermarket chains decided what the interventions should be also imposes limitations on wider interpretation of the findings. Each of the 7 different interventions applied to different categories of foods without any rationale made explicit to the research team—for example, chocolate confectionary was removed from prominent positions, higher fibre breakfast cereals were placed at eye level, and price discounts were applied to fruit and vegetables. This makes it hard to determine whether observed impacts were unique to specific combinations of intervention and food category. Indeed, rather than particular marketing interventions being more effective than others across the board, it is possible that complex interplays between food category, marketing intervention, and other contextual aspects (such as shop and customer characteristics) interact to produce changes in sales.The “squeezed balloon effect” proposes that restrictions on specific aspects of marketing may lead to compensatory increases in others [13]. For example, restricting television advertising of less healthy foods during and around children’s programmes in the UK was associated with increased exposure of adults to these adverts [14]. Wider compensation between, as well as within, media (for example, TV restrictions leading to more online marketing) may also be expected. It is possible that supermarkets willing to engage in university-assessed marketing changes may have self-policed any simultaneous compensatory activities, and, anyway, these would not necessarily have been identified in the studies by Piernas and colleagues. Any real-life compensation as the whole grocery sector adapts to government-imposed marketing restrictions may be difficult to predict. This reinforces the need for postimplementation evaluation.The squeezed balloon effect means that the most effective marketing restrictions may be those that target marketing of the same products through multiple simultaneous interventions. In Chile, near-simultaneous implementation of front-of-pack warning labels, advertising restrictions, and a prohibition of sales in schools of products high in calories, sodium, sugar, or saturated fat were associated with substantial declines in purchases of targeted foods and nutrients [15]. This approach is also the underlying strategy in England where near-simultaneous restrictions on TV and online advertising of less healthy foods are planned for the whole of the UK alongside the England-specific bans on location and price-based promotions [16].Despite the innovative approach in England, neither the regulations on TV and online advertising of less healthy foods nor on price and location-based promotions of these foods have cleared the parliamentary process. The UK government recently accepted an amendment to the TV and online advertising restrictions to give the Secretary of State for Health and Social Care power to delay implementation [17]. The restrictions on price and location-based promotions may be under threat of being dropped altogether [18].Piernas and colleagues’ studies add to the accumulating evidence that restricting marketing on less healthy foods and encouraging marketing on healthier foods may be an effective way to support public health. Theory and a range of evidence suggest that simultaneous restrictions on a variety of different types of less healthy food marketing are likely to be the most effective ways of reducing exposure to this marketing. The UK government has proposed this approach in England on a number of occasions. That implementation continues to hang in the balance is a sad indictment of our collective inability to create a world that supports everyone to eat in the way they want to, rather than the way the marketers want for us.  相似文献   

11.
Analyses for phytate by an indirect precipitation method and for the minerals calcium (Ca), zinc (Zn), iron (Fe), copper (Cu), and manganese (Mn) by atomic absorption spectrophotometry were carried out on 100 foods available in New Zealand. Foods with 1% phytate (dry weight basis) included untoasted muesli, rolled oats, wheat germ, wheat bran, soybean, and some soy products. Most breads contained between 0.35 and 0.60% phytate; legumes on average had 0.62% phytate, as did snack bars. There was a wide variation in Ca and Zn contents: There was a tenfold variation in Ca content among the legume products, whereas there was a seventyfold variation in Zn content among the cereals. The phytate: Zn molar ratio, which is presumed to indicate the biovailability of Zn, was above 20∶1 for two-thirds of the cereals and almost all of the snack bars; it was above 15∶1 for one-third of the breads, almost all of the legumes, and half of the legume products. These high phytate: Zn molar ratios, as well as some Ca: phytate molar ratios above 6∶1, indicate that there might be a reduced biovailability of Zn in many of the foods analyzed in this study.  相似文献   

12.
13.
Abiotic stress and control of grain number in cereals   总被引:1,自引:0,他引:1  
Dolferus R  Ji X  Richards RA 《Plant science》2011,181(4):331-341
Grain number is the only yield component that is directly associated with increased grain yield in important cereal crops like wheat. Historical yield studies show that increases in grain yield are always accompanied by an increase in grain number. Adverse weather conditions can cause severe fluctuations in grain yield and substantial yield losses in cereal crops. The problem is global and despite its impact on world food production breeding and selection approaches have only met with limited success. A specific period during early reproductive development, the young microspore stage of pollen development, is extremely vulnerable to abiotic stress in self-fertilising cereals (wheat, rice, barley, sorghum). A better understanding of the physiological and molecular processes that lead to stress-induced pollen abortion may provide us with the key to finding solutions for maintaining grain number under abiotic stress conditions. Due to the complexity of the problem, stress-proofing our main cereal crops will be a challenging task and will require joint input from different research disciplines.  相似文献   

14.
15.
Small grains in the USDA World Collection total about 44,500 accessions. This constitutes a valuable, growing, and much used gene bank. It contains only a few duplicates, but many individual genes are represented over and over. Therefore, the probability of adding altogether new genes to the bank is diminishing, and only as truly exotic, untapped gene pools are discovered in the world is the trend altered. It is feared that agricultural improvement and increased utilization and grazing of natural areas is erasing forever some rich, but unknown, gene centers. Future generations may, therefore, have to do without needed genes that we have now and do not know how to preserve. They would have to wait until nature evolved them, or they would have to find and use ways to induce the genes by directed evolutionary processes.  相似文献   

16.
Calcium (Ca), magnesium (Mg), copper (Cu), iron (Fe), manganese (MD), and zinc (Zn) concentrations were measured in whole mice (five sizes) and rats (six sizes). Ca concentrations increased with age in both mice (1.2–2.3%) and rats (1.9–3.3%). Mg levels ranged from 0.09 to 0.13% (mice) and from 0.11 to 0.18% (rats), with the medium-size class of both species having the highest values. Cu (7.9–19.2 and 10.8–60.6 mg/kg) and Zn (58.0–82.5 and 73.2–113.6 mg/kg) generally decreased with age in both species, while Mn levels tended to increase with age (0.2–13.1 mg/kg, mice; 6.2–28.3 mg/kg, rats). Fe values were highest in neonates and adult size classes, ranging from 113.4 to 181.3 mg/kg (mice) and 111.3 to 332.6 mg/kg (rats). Rats usually contained higher concentrations of individual minerals than equivalent age categories of mice, even though both were fed identical diets. All rodents analyzed generally met known dietary requirements of mammalian carnivores, but differences between mice and rats were apparent. Specific mineral nutrient requirements for carnivorous birds and reptiles have not been determined. © 1996 Wiley-Liss, Inc.  相似文献   

17.
The value of three cereal aphid species as food for a generalist predator   总被引:4,自引:0,他引:4  
The value of the cereal aphid species Metopolophium dirhodum (Wlk.), Sitobion avenae (F.) and Rhopalosiphum padi (L.) as prey for the linyphiid spider Erigone atra (Bl.) was assessed. Fecundity of females was determined for spiders fed on eight experimental diets: three single‐species aphid diets, a mixed diet of all three aphid species, three mixed diets with each aphid species in combination with fruit flies Drosophila melanogaster (Meig.), and pure D. melanogaster as a high quality comparison diet. The development and survival of first‐instar juveniles fed on three diets of single aphid species, and on a diet of Collembola were compared with those subjected to starvation. Prey value for adult females was assessed by egg production, hatching success and offspring size. In pure diets all three aphid species were of low value to the spiders, causing a rapid decline in egg production and supporting no growth of significance of first‐instar juveniles. No difference in value of aphid species of single‐species aphid diets was found in the fecundity experiment, while a ranking of aphid species of M. dirhodum > R. padi > S. avenae was revealed in the survivorship experiment. A mixed‐aphid diet was not found to be advantageous compared with single‐species aphid diets, and no advantage of including aphids in mixed diets with fruit flies was found. Metopolophium dirhodum and R. padi were neutral in mixed diets, while a diet of S. avenae and fruit flies caused reduced egg production compared with the pure diet of fruit flies, revealing a toxic effect of S. avenae on the spider. The value‐ranking of aphid species in mixed diets was similar to that of single‐species diets. A similar ranking of aphid species was found for different fitness parameters (fecundity of adult females and development of juveniles). A ranking of aphids by offspring size of mothers on aphid‐only diets was S. avenae > M. dirhodum > R. padi. All aphid‐fruit fly diets resulted in larger offspring than a diet of only D. melanogaster, with the overall largest offspring being produced on the diet of M. dirhodum and fruit flies.  相似文献   

18.

Background

Carotid plaque area is a strong predictor of cardiovascular events. High homocysteine levels, which are associated with plaque formation, can result from inadequate intake of folate and vitamin B12. Now that folic acid fortification is widespread in North America, vitamin B12 has become an important determinant of homocysteine levels. We sought to determine the prevalence of low serum levels of vitamin B12, and their relation to homocysteine levels and carotid plaque area among patients referred for treatment of vascular disease since folic acid fortification of enriched grain products.

Methods

We evaluated 421 consecutive new patients with complete data whom we saw in our vascular disease prevention clinics between January 1998 and January 2002. We measured total carotid plaque area by ultrasound and determined homocysteine and serum vitamin B12 levels in all patients.

Results

The patients, 215 men and 206 women, ranged in age from 37 to 90 years (mean 66 years). Most were taking medications for hypertension (67%) and dyslipidemia (62%). Seventy-three patients (17%) had vitamin B12 deficiency (vitamin B12 level < 258 pmol/L with homocysteine level > 14 μmol/L or methylmalonic acid level > 271 nmol/L). The mean area of carotid plaque was significantly larger among the group of patients whose vitamin B12 level was below the median of 253 pmol/L than among those whose vitamin B12 level was above the median: 1.36 (standard deviation [SD] 1.27) cm2 v. 1.09 (SD 1.0) cm2; p = 0.016.

Conclusions

Vitamin B12 deficiency is surprisingly common among patients with vascular disease, and, in the setting of folic acid fortification, low serum vitamin B12 levels are a major determinant of elevated homocysteine levels and increased carotid plaque area.Elevated plasma total homocysteine levels are a strong, graded independent risk factor for stroke and myocardial infarction.1,2 Mechanisms by which homocysteine may cause vascular disease include a propensity for thrombosis and impaired thrombolysis, increased production of hydrogen peroxide, endothelial dysfunction and increased oxidation of low-density lipoproteins and Lp(a) lipoproteins.3 Folic acid fortification of enriched cereal grain products began in North America in March 1996 and was made mandatory in 1998. Fortification has reduced the number of neural tube defects by half,4 which is clearly a beneficial outcome, but so far it has had little impact on cardiovascular mortality.5Carotid plaque area is a strong predictor of cardiovascular events.6 High homocysteine levels, which are associated with plaque formation, can result from inadequate intake of folate and vitamin B12. Now that folic acid fortification is widespread, vitamin B12 has become an important determinant of homocysteine levels.7 We sought to determine the prevalence of low serum levels of vitamin B12, and their relation to homocysteine levels and carotid plaque area among patients referred for treatment of vascular disease since folic acid fortification of enriched grain products.  相似文献   

19.
20.
Samples of wheat and rye heads with evident black discoloration were collected in 1986 and 1987. Four fungal genera colonized such heads:Alternaria, Cladosporium, Drechslera, andEpicoccum. In chaff of wheat (19%) and rye (10%) samples alternariol was present in amounts up to 1.8mg/kg, and alternariol methyl ether up to 0.51 mg/kg. In 1 out of 21 wheat samples alternariol was also present in kernels (0.59mg/kg).  相似文献   

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