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Mineral Ions (mineral + ion)
Selected AbstractsThe effect of gamma irradiation on the microbial load, mineral concentration and sensory characteristics of liquorice (Glycyrrhiza glabra L)JOURNAL OF THE SCIENCE OF FOOD AND AGRICULTURE, Issue 1 2003Mahfouz Al-Bachir Abstract Ground liquorice roots were exposed to various doses (0, 5, 10, 15 and 20,kGy) of gamma radiation from a 60Co source. Irradiated and non-irradiated samples were stored at room temperature. Microbial population, viscosity, concentrations of some minerals and the sensory properties of the extracts were evaluated after 0 and 12 months of storage. Tests carried out immediately after irradiation showed that the microbial count had been reduced and that the dose required to reduce the count by 1 log cycle (D10) was about 2,kGy. No effect was observed on the total dissolved solids in extracts of liquorice roots. Glycyrrhizinic acid concentration in the extracts and the viscosities of suspensions produced from irradiated roots were lower than those from non-irradiated ones. Sensory evaluation indicated that there were no significant differences (P,<,0.05) in colour, taste or flavour between extracts produced from irradiated and non-irradiated roots. However, after 12 months of storage, some mineral ion (Na+, Ca2+ and K+) concentrations in extracts produced from irradiated roots were lower than in those from non-irradiated ones; no significant differences (P,<,0.05) in viscosity were found between suspensions of irradiated and non-irradiated roots. © 2002 Society of Chemical Industry [source] The influence of pH and digestion with commercial enzymes on calcium adsorption in casabeINTERNATIONAL JOURNAL OF FOOD SCIENCE & TECHNOLOGY, Issue 9 2006Petra Beatriz Navas Summary The Ca2+ binding capacity of a sample of casabe made from cassava (Manihot esculenta) was evaluated by using adsorption isotherms after a digestion process with commercial enzymes. It was found that enzymatic treatment increased the ability of vegetable material to retain calcium and to release endogenous mineral ions as a consequence of possible modifications to the carbohydrate matrix. Untreated casabe did not release mineral ions. pH also influenced the retention of Ca2+: at pH 4.5 release was the main process but adsorption increases with alkalinity up to pH 8.5. The Ca concentrations at which neither adsorption nor release occurred [Ca2+]e were as follows: 5.2 mm (pH 4.5), 3.5 mm (pH 7.1), and 0.63 mm (pH 8.5). The pH effect was explained by an increase in the density of negatively charged functional groups produced by ionization reactions at pH below the point of zero net charge (pHo) which was evaluated by using the Gouy,Chapman double layer model. Values of pHo were 6.4 for raw material and 4.1 after digestion with enzymes. In both cases, the density of positively charged sites below pHo was much higher that the density of negatively charged sites above pHo. [source] Metal ion enhancement of fungal growth, gene expression and aflatoxin synthesis in Aspergillus flavus: RT-PCR characterizationJOURNAL OF APPLIED MICROBIOLOGY, Issue 6 2003R. Cuero Abstract Aims: To determine the effect of mineral ions (e.g., Zn2+, Cu2+, and Fe2+) on the enhancement of fungal growth, total RNA, aflatoxin pathway gene expression, and production of aflatoxin and its precursor O -methylsterigmatocystin (OMST). Methods and Results: The influence of the metal ions, as a single or mixed treatments, was observed in submerged cultures of toxigenic Aspergillus flavus through changes in the fungal RNA or aflatoxin pathway gene (omtA) by reverse transcription-polymerase chain reaction (RT-PCR) levels, and also in fungal dry-weight accumulation, aflatoxin and OMST production. Conclusions: The ion treatments induced changes of fungal total RNA, mRNA levels, associate fungal growth, biosynthesis of aflatoxin and OMST, and enhanced expression of RT-PCR. Significance and Impact of Study: Demonstrates at the cellular and molecular level, the significant effects of metal ions on both fungal growth and production of aflatoxin. [source] Phytogenic resources of halophytes of Central Asia and their role for rehabilitation of sandy desert degraded rangelandsLAND DEGRADATION AND DEVELOPMENT, Issue 4 2009K. N. Toderich Abstract Based on soil characteristics, watertable level, mineral composition of plant biomass, morphological/reproductive traits and carbon discrimination values, a new concept for the classification of halophytes was developed. Six main groups of halophytes have been described within the desert flora of Central Asia. Significant changes on chemical contents of ions: Cl,, SO, HCO, Na+, K+, Ca2+ and Mg2+among 23 studied halophytic forage species were revealed. Alhagi pseudoalhagi, Poaceae spp., Artemisia diffusa containing minimum concentration of mineral ions were categorised as relatively more palatable and valuable feed for livestock on open grazing and as hay. Fresh biomass of forage species growing under highly saline soils sharply decreased with increasing of salinity gradient. Potassium concentration was found highest in Kochia scoparia, Agropyron desertorum, closely followed by Atriplex nitens, Suaeda salsa, while annuals Salsola spp., Bromus tectorum, Aeluropus littoralis, Tamarix hispida, Eremopyrum orientale, Agropyron desertorum contain low amount of mineral ions because excess of salts are exuded through salt glands present abundantly on the surface of the epidermis. Native and exotic, both C3 and C4, halophytes are suitable for reclamation of degraded lands have been proven very useful in demonstration trials. The fresh biomass of investigated C3 plants sharply decreased with the increasing of soil salinity gradient. An integrated Biosaline Agriculture model for sustainable and integrated use of marginal mineralised water resources and salt-affected soils through involvement of food,feed salt/drought tolerant crops and forage legumes to improve food security, alleviate poverty and enhance ecosystem health in smallholder crop,livestock systems has been demonstrated. Copyright © 2009 John Wiley & Sons, Ltd. [source] Natural selection for salt tolerance quantitative trait loci (QTLs) in wild sunflower hybrids: Implications for the origin of Helianthus paradoxus, a diploid hybrid speciesMOLECULAR ECOLOGY, Issue 5 2003C. Lexer Abstract For a new diploid or homoploid hybrid species to become established, it must diverge ecologically from parental genotypes. Otherwise the hybrid neospecies will be overcome by gene flow or competition. We initiated a series of experiments designed to understand how the homoploid hybrid species, Helianthus paradoxus, was able to colonize salt marsh habitats, when both of its parental species (H. annuus×H. petiolaris) are salt sensitive. Here, we report on the results of a quantitative trait locus (QTL) analysis of mineral ion uptake traits and survivorship in 172 BC2 hybrids between H. annuus and H. petiolaris that were planted in H. paradoxus salt marsh habitat in New Mexico. A total of 14 QTLs were detected for mineral ion uptake traits and three for survivorship. Several mineral ion QTLs mapped to the same position as the survivorship QTLs, confirming previous studies, which indicated that salt tolerance in Helianthus is achieved through increased Ca uptake, coupled with greater exclusion of Na and related mineral ions. Of greater general significance was the observation that QTLs with effects in opposing directions were found for survivorship and for all mineral ion uptake traits with more than one detected QTL. This genetic architecture provides an ideal substrate for rapid ecological divergence in hybrid neospecies and offers a simple explanation for the colonization of salt marsh habitats by H. paradoxus. Finally, selection coefficients of +0.126, ,0.084 and ,0.094 for the three survivorship QTLs, respectively, are sufficiently large to account for establishment of new, homoploid hybrid species. [source] Ion transport in roots: measurement of fluxes using ion-selective microelectrodes to characterize transporter functionPLANT CELL & ENVIRONMENT, Issue 1 2001I. A. Newman ABSTRACT The transport of mineral ions into and out of tissues and cells is central to the life of plants. Ion transport and the plasma membrane transporters themselves have been studied using a variety of techniques. In the last 15 years, measurement of specific ion fluxes has contributed to the characterization of transport systems. Progress in molecular genetics is allowing gene identification and controlled expression of transporter molecules. However the molecular expression of transporter gene products must be characterized at the functional level. The ion-selective microelectrode technique to measure specific ion fluxes non-invasively is ideally suited to this purpose. This technique, its theory, its links with others and its application and prospects in plant science, are discussed. Ions studied include hydrogen, potassium, sodium, ammonium, calcium, chloride and nitrate. Applications discussed include: solute ion uptake by roots; gravitropism and other processes in the root cap, meristematic and elongation zones; Nod factor effect on root hairs; osmotic and salt stresses; oscillations; the effects of light and temperature. Studies have included intact roots, leaf mesophyll and other tissues, protoplasts and bacterial biofilms. A multi-ion capability of the technique will greatly assist functional genomics, particularly when coupled with imaging techniques, patch clamping and the use of suitable mutants. [source] New food sources of essential trace elements produced by biotechnology facilitiesBIOTECHNOLOGY JOURNAL, Issue 10 2007Vladimir K. Mazo Abstract Population satiety with trace elements (TE) is a problem that is widely discussed in nutrition science. For optimal nutrition, the form of TE eaten in food is very important. Organic forms of TE in nutrition are appropriate as human metabolism has adapted to these kinds of nutrients during species evolution. This is now considered a reason for the beneficial use of biotechnologically produced TE sources in human food. Advanced matrixes for TE incorporation are unicellular organisms such as yeast, lactobacilli and Spirulina. Addition of inorganic salts at certain concentrations into cultivation media enables the mineral ions to incorporate into the microbial biomass. As a consequence, the biomass becomes enriched with organic forms of incorporated TE, which are presented by their complexes with amino acids, proteins and probably lipids and polysaccharides. In addition, a new direction of research has made good advances, in which technology has been developed for production of organic forms of TE through complex formation between transition metals (zinc, copper, manganese, chromium, iron) with amino acids and peptides formed during enzymatic hydrolysis of food protein. This brief review discusses the results demonstrating the advances in the biotechnological production of new TE sources, to obtain food components destined for wide prophylaxis of TE deficiency or for dietary treatment of the adverse consequences of these deficiencies. [source] | |||||||||||||