Macroelements
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Minerální látky rozdělujeme podle zastoupení v organismu na makroprvky a mikroprvky. Mezi makroprvky patří vápník, fosfor, draslík, sodík, chlór, hořčík a síra. Stejně jako u makronutrientů i u mikronutrientů, mezi které patří i minerální látky, je třeba správně vybalancovat jejich denní příjem. Komerčně vyráběná krmiva pro psy a kočky se řídí nutričními doporučeními, která uvádějí minimální a v některých případech maximální hodnoty pro vybrané živiny obsažené v krmivu. Zvláště u psů je někdy těžké správně navolit přísun jednotlivých živin podle doporučení, vzhledem k velké rozmanitosti plemen a velikostí. Při nerespektování nutričních potřeb psů a koček hrozí riziko nedostatečného, nebo naopak nadbytečného přísunu minerálních látek v dietě. Toto riziko je především problémem u doma připravených dávek. V případě nedodržení požadavků na optimální přísun minerálů do organismu může dojít ke zdravotním problémům. Nejvíce diskutované zdravotní potíže jsou spojeny s dysbalancí v množství vápníku a fosforu a jejich vzájemném poměru, která následně může nejčastěji vyústit v rachitidu nebo osteomalacii. Nejvíce řešeným tématem v této oblasti jsou problémy skeletu u rostoucích psů velkých a obřích plemen a sekundární nutriční hyperparatyreóza. U ostatních makroprvků jsou projevy případného nedostatečného nebo nadbytečného přijatého množství méně časté a příznaky jejich nerovnováhy v organismu se manifestují převážně nespecificky (např. anorexií, neklidem, zpomaleným růstem nebo ztrátou srsti). Je proto nezbytné věnovat značnou pozornost vyváženému přísunu živin v krmivu pro psy a kočky a je třeba neopomíjet i vhodné zastoupení minerálů v dietě.
Minerals are divided according to the representation in the organism into macroelements and microelements. Macroelements include calcium, phosphorus, potassium, sodium, chlorine, magnesium and sulfur. For both macronutrients and micronutrients, which include minerals, the daily intake must be properly balanced. Commercially produced dog and cat food is governed by nutritional recommendations, which state minimum and in some cases maximum values for selected nutrients contained in the food. Especially in dogs, it is sometimes difficult to choose the right supply of individual nutrients according to the recommendations, due to their large variety of breeds and sizes. If the nutritional needs of dogs and cats are not respected, there is a risk of insufficient or, on the contrary, excessive supply of minerals in the diet. This risk is especially a problem for home-prepared food. If the requirements for the optimal supply of minerals to the body are not met, health problems can occur. The most discussed health problems are associated with imbalances in the amount of calcium and phosphorus and their ratio, which can subsequently most often result in rickets or osteomalacia. The most common topics in this area are skeletal problems in growing dogs of large and giant breeds and secondary nutritional hyperparathyroidism. For other macroelements, manifestations of possible insufficient or excessive intake are less frequent and symptoms of their imbalance in the body are manifested mainly non-specifically (e. g. anorexia, unrest, slow growth or hair loss). It is therefore necessary to pay considerable attention to a balanced supply of nutrients and the appropriate representation of minerals in the feed ration for dogs and cats must not be neglected.
Differences in the contents of macroelements (P, Ca, Mg, K, Na), trace elements (Fe, Zn, Cu, Mn, B, Cr) and toxic elements (Pb, Cd, Hg) in food products prepared from freshwater algae or seaweed are discussed. Generally, the contents of macroelements are low. On the other hand, high contents of trace elements were observed. The order of macro- and trace elements in the products is Fe > Mn > B > Zn > K > Na > Mg > Cu > Ca > P > Cr and that of toxic elements Pb > Cd >Hg. The highest Fe contents were found in products from red seaweed Porphyra tenera, blue-green freshwater algae Spirulina pacifica and green freshwater algae Chlorella pyrenoidosa, 1833, 1480 and 1185 mg kg-1, respectively. Higher amounts of toxic elements were found in seaweed products. The highest contents of Cd and Hg were in a product from brown seaweed Wakame instant, 1.010 and 0.037 mg kg-1, respectively. The highest Pb values were in Corsican tea from red seaweed Digenes simplex, 1.509 mg kg-1 The French limits for the toxic elements were not exceeded in the investigated products.
The article summarizes outcomes of a biomass study conducted in a young speckled alder plantation on a cold mountain site. At this location, the previously existing old forest was clear felled because of damage from air pollution, and present-day surface humus is in need of restoration. The intention of this study was to quantify the biomass and nutrients accumulated by alders and their components and assess whether the initial fertilization resulted in increased biomass production and nutrient accumulation in the biomass. Besides the control, two fertilized treatments were installed. In the surface treatment (SUT), the amendment was applied as a base dressing in small circles around trees. In the planting-hole treatment (PHT), the amendment was incorporated into soil inside the planting holes. Five growth seasons after planting and fertilization, six alders from each treatment were harvested including roots. Their biomass was quantified and analyzed for macroelements. The greatest pool of dry mass (DM) was branches in the control and stem wood in the fertilized treatments. The greatest pools of macroelements were leaves and branches. The most pronounced effects of fertilization were recorded in the DM and consequently in the absolute quantities of nutrients. The DM of an average tree in the control, SUT, and PHT was 85, 226, and 231 g, respectively. The absolute contents of nutrients per tree in the fertilized treatments showed the following increases, as compared with the control: (N) 2.5-2.6 times; (P) 1.6-2.4 times; (K) 1.8-2.1 times; and (Mg) 1.8-2.0 times, respectively. Speckled alder responded positively to fertilization.
- MeSH
- biomasa MeSH
- dřevo účinky léků růst a vývoj MeSH
- kořeny rostlin chemie účinky léků růst a vývoj MeSH
- listy rostlin chemie účinky léků růst a vývoj MeSH
- olše chemie účinky léků růst a vývoj MeSH
- průmyslová hnojiva * MeSH
- půda MeSH
- regenerace a remediace životního prostředí metody MeSH
- roční období MeSH
- znečištění ovzduší * MeSH
- Publikační typ
- časopisecké články MeSH
- práce podpořená grantem MeSH
Agaricus bisporus is the most commonly cultivated and consumed mushroom species. The aim of this study was to compare the profile of macro- and trace elements in A. bisporus fruit bodies produced commercially in 19 countries in 2018 and distributed worldwide (32 analyzed objects). Trace elements with unknown biological roles were also determined. The content of 36 elements (of 70 taken into account) revealed significant differences among the analyzed objects. Contents of Ca, K, Mg, Na and S varied in wide ranges of 425-2430, 12740-40940, 610-3240, 98-430 and 1030-2650 mg kg-1 dw, respectively. The fruit bodies were characterized by a generally similar content of trace elements with some clear exceptions. Rankings of the objects according to the decreased amount of macroelements, trace elements and all elements jointly, show that mushrooms are significantly diverse as regards the content of particular elements of the mentioned group. The analyzed fruit bodies displayed a relatively high content of Ca, Mo and Se, and a high K/Na ratio. Regardless of origin, A. bisporus did not constitute a source of significant levels of Al, Cd or rare earth elements. An increased level of As and Pb in mushrooms from several producers indicates a need for additional measures to reduce potential dietary exposures to these toxicants.
- MeSH
- Agaricus chemie MeSH
- arsen analýza MeSH
- celosvětové zdraví MeSH
- olovo analýza MeSH
- průzkumy a dotazníky * MeSH
- stopové prvky analýza MeSH
- Publikační typ
- časopisecké články MeSH
Současný výzkum v oblasti lékových interakcí se znovu vrací k otázce vlivu potravy na terapeutickou hodnotu léčiv, neboť se ukazuje, že naše poznání je v tomto směru stále omezené. Farmakologickou léčbu (její průběh a výsledek) mohou významně ovlivňovat některé složky potravy (indoly, aminokyseliny, bioflavonoidy, třísloviny, glykosidy, vitaminy, mikro a makroelementy, aj.). Ačkoliv řada interakcí léků s potravou je známa již dlouho, bývá vliv potravy na terapeutickou účinnost a bezpečnost podávaných léčiv často podceňován a málokdy se počítá v terapeutických úvahách se změnami nutrice jako s možnou Pncinou selhání léčby. článek podává ucelený přehled o principech dávno známých interakcí léků s potravou, stejně tak i o novějších poznatcích z té to oblasti (např. o P-glykoproteinovém transportu, indukci a inhibici CYP450 hepatálních a intestinálních izoenzymů, o roli koenzymu Q10 v bezpečnosti tricyklických antidepresiv apod.). Cílem článku je seznámit odbornou veřejnost s významem nutričního režimu pro účinnost a bezpečnost léků a podpořit tak využití těchto poznatků v běžné klinické praxi.
Contemporary research in the field of drug interaaions resolve the question of the nutrition influence on the therapeutic value of drugs. Dur knowledge in this area is still limited. Many food components may change the outcomes of the pharmacotherapy (e.g. indoles, aminoacids, bioflavonoids, glycosides, vitamines, micro- and macroelements, etc.). Athrough some of the drug-food interaaions are known for a long time, the professionals very often underestimate the real impaa of food on efficacy and safety of drug treatment. In the case of uneffeaiveness or side effects of pharmacotherapy, nutrition is not always considered as a possible cause of the drug treatment failure. The article provides the comperhensive overview of main principles of drug-food interaaions- not even of the old ones, but discusses also the new knowledge in this field (e.g. the role of P-glycoprotein transport induaion and inhibition of CYP450 hepatic and intestinal izoenzymes, the role of coenzyme Q10 in safety of tricyclic antidepressants, etc.). The aim of this article is to emphasize the importance of food-drug interactions and to enable praaicing these knowlegde in clinical work.
Starch and lipids are key components of algal cells and responsible for buffering variable supplies of energy and carbon that are vital for cell growth and reproduction, particularly DNA replication, nuclear and cellular division. The basic characteristics of energy reserves, their ultrastructure and localization inside the cell, regulation of their synthesis in relation to cell cycle phases, and their control by external factors, including light intensity, temperature, and carbon dioxide are described. Over the last two decades, research in this field has been boosted by possible biotechnological applications of algae for the production of biofuels from energy conserving compounds (bioethanol from starch and biodiesel from lipids). Recent findings on mechanisms that lead to an accumulation of exceptionally high levels of starch and lipids in algae will be summarized in this review. Macroelement (N, S, P) limitation, or depletion in mineral medium, as the most widely used approaches for enhancing both starch and lipid accumulation, are reviewed in detail. Potential biotechnological strategies for the economically viable overproduction of lipid and starch, such as a two-step procedure exploiting the effects of nutrient limitation and depletion, as well as the means and rationale for selecting appropriate strains, are discussed.
The alga Parachlorella kessleri, strain CCALA 255, grown under optimal conditions, is characterized by storage of energy in the form of starch rather than lipids. If grown in the complete medium, the cultures grew rapidly, producing large amounts of biomass in a relatively short time. The cells, however, contained negligible lipid reserves (1-10% of DW). Treatments inducing hyperproduction of storage lipids in P. kessleri biomass were described. The cultures were grown in the absence or fivefold decreased concentration of either nitrogen or phosphorus or sulfur. Limitation by all elements using fivefold or 10-fold diluted mineral medium was also tested. Limitation with any macroelement (nitrogen, sulfur, or phosphorus) led to an increase in the amount of lipids; nitrogen limitation was the most effective. Diluted nutrient media (5- or 10-fold) were identified as the best method to stimulate lipid overproduction (60% of DW). The strategy for lipid overproduction consists of the fast growth of P. kessleri culture grown in the complete medium to produce sufficient biomass (DW more than 10 g/L) followed by the dilution of nutrient medium to stop growth and cell division by limitation of all elements, leading to induction of lipid production and accumulation up to 60% DW. Cultivation conditions necessary for maximizing lipid content in P. kessleri biomass generated in a scale-up solar open thin-layer photobioreactor were described.
- MeSH
- biomasa MeSH
- biotechnologie MeSH
- chlorofyl analýza metabolismus MeSH
- Chlorophyta metabolismus MeSH
- fotobioreaktory MeSH
- kultivační média MeSH
- lipidy biosyntéza MeSH
- mastné kyseliny analýza metabolismus MeSH
- metabolismus lipidů MeSH
- mikrořasy metabolismus MeSH
- oxid uhličitý metabolismus MeSH
- škrob analýza metabolismus MeSH
- Publikační typ
- časopisecké články MeSH
The widely used means of investigating animal mineral profiles are blood serum or plasma and internal organ tissues. The acquisition of these types of samples can be invasive and requires much effort. These factors become key obstacles in the case of rare and elusive species such as the Western Derby eland (Taurotragus derbianus derbianus, WDE), which is a critically endangered antelope with a current distribution limited to the Niokolo Koba National Park, and two wildlife reserves in Senegal. One of the solutions to this problem is to collect easily accessible samples, such as faeces or fur, which may provide valid information about animal mineral status. Our study focuses on determining the macroelement and microelement levels in animal blood serum, hair, and faeces, and analysing their correlations to evaluate whether hair and/or faeces can be used as a proxy for blood mineral levels. Samples were collected from 11 individual WDEs (6 males, 5 females) during translocations within two reserves. Correlations of mineral concentrations in the blood, hair, and faeces were not found except for Fe in the faeces, which was positively correlated with Fe in the hair (r = 0.64, P < 0.05) and blood (r = 0.69, P < 0.05). The lack of correlations among the different types of samples may be because of the low number of samples; hence, we recommend conducting further research with a broader dataset. Our findings, however, currently indicate that faeces and fur analyses cannot stand alone for the assessment of the mineral status and the determination of WDEs' potential mineral deficiencies.
