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Tytuł:
Microemulsions as Carriers of Omega-3 Polyunsaturated Fatty Acids
Mikroemulsje jako nośniki kwasów tłuszczowych omega-3
Autorzy:
GÓRSKA, Anna
KRUPA, Anna
Powiązania:
https://bibliotekanauki.pl/articles/1033822.pdf
Data publikacji:
2013
Wydawca:
Zakład Opieki Zdrowotnej Ośrodek Umea Shinoda-Kuracejo
Tematy:
docosahexaenoic acid (DHA)
eicosapentaenoic acid (EPA)
functional foods
microemulsions
microencapsulation
α-linolenic acid
Opis:
Design of novel foodstuffs rich in natural bioactive substances is one of the main research field in the food industry. There are many clinical reports on beneficial effects of either docosahexaenoic acid (DHA) or eicosapentaenoic acid (EPA) on health. In general n-3 polyunsaturated fatty acids (n-3 PUFAs) are significant structural components of cell membranes. Since DHA and EPA represent exogenous fatty acids, their level in the human body depends on the dietary intake. Therefore there is a need to enrich food by bioactive compounds. It has been shown that the application of polyunsaturated fatty acids such as α-linolenic acid in traditional foodstuffs permits to obtain a kind of functional food that can be used to improve both health and skin condition. However low stability of natural bioactive components limits their application in food, especially on an industrial scale. Due to this fact efforts are made to prepare new functional food formula containing n-3 PUFAs in a stable form. Microencapsulation process is a well known attempt to prevent their oxidation. Preparation of food-grade microemulsions containing polyunsaturated fatty acids to improve the stability and to ensure pleasant sensory properties of food is discussed in the present study.
Źródło:
Medicina Internacia Revuo; 2013, 25, 101; 211- 219
0465-5435
Pojawia się w:
Medicina Internacia Revuo
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Badanie stężenia kwasu mlekowego, otrzymanego w procesie fermentacji mlekowej laktozy, zawartej w serwatce poprodukcyjnej przy udziale Lactobacillus
Study of concentration of lactic acid obtained in the process of lactic fermentation of lactose contained in the spent whey using Lactobacillus
Autorzy:
Maślanka, S.
Kos, A.
Bańczyk, M.
Czopek, I.
Adam, Ł.
Dorszewska, J.
Starczewska, K.
Powiązania:
https://bibliotekanauki.pl/articles/141850.pdf
Data publikacji:
2015
Wydawca:
Stowarzyszenie Inżynierów i Techników Przemysłu Chemicznego. Zakład Wydawniczy CHEMPRESS-SITPChem
Tematy:
kwas mlekowy
bakterie kwasu mlekowego
serwatka kwaśna
lactic acid
lactic acid bacteria
acid whey
Opis:
Serwatka kwaśna jest groźnym ekologicznie odpadem, będącym produktem ubocznym powstającym w przemyśle mleczarskim. Z uwagi na wysoką zawartość laktozy, odpad ten może być wykorzystywany jako surowiec w procesie fermentacji mlekowej, w którym ulega dalszej przemianie do kwasu mlekowego, przy udziale bakterii fermentacji mlekowej. Niniejsza publikacja stanowi przegląd literaturowy dotyczący procesu fermentacji mlekowej oraz opis badań własnych nad efektywnością procesu fermentacji mlekowej laktozy, pozyskanej z serwatki poprodukcyjnej, do kwasu mlekowego.
Acid whey is an environmentally hazardous waste which is a by-product produced in the dairy industry. Due to the high lactose content, the waste can be used as a raw material for lactic fermentation process, where it is converted further to lactic acid using lactic acid bacteria. This publication is a literature review on lactic acid fermentation process and includes description of own research on efficiency of lactic acid fermentation of lactose, obtained from spent whey, to lactic acid.
Źródło:
Chemik; 2015, 69, 4; 241-251
0009-2886
Pojawia się w:
Chemik
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Zastosowanie biostymulatorów w hodowli i ochronie sadzonek dębu szypułkowego (Quercus robur L.) w gruntowej szkółce leśnej
Application of biostimulators in the growth and protection of pedunculated oak (Quercus robur L.) seedlings in bare-root nursery
Autorzy:
Buraczyk, W.
Żybura, H.
Ostaszewska, E.
Studnicki, M.
Aleksandrowicz-Trzcińska, M.
Powiązania:
https://bibliotekanauki.pl/articles/979060.pdf
Data publikacji:
2020
Wydawca:
Polskie Towarzystwo Leśne
Tematy:
plant biostimulants
chitosan
humic acid
fulvic acid
silicon
pedunculate oak
Opis:
Pedunculate oak is a species of major economic importance in Polish forests. This species seedlings constitute 18.9% of the nursery production in the country. One of the most widespread fungal disease these oaks face is the oak powdery mildew induced by Erysiphe alphitoides. Nursery production is on the lookout for environment−friendly means of plant protection as well as growth simulators capable of raising levels of productivity. Our objectives was to assess two preparation treatments regarded as biostimulators (registered as fertilisers under the names Apol−Humus and Apol−Hum Chelat) in the raising of seedlings of pedunculate oak in bare−root nursery conditions. The experiment included 6 variants with seedlings treated with the above agents, protected against mildew in the traditional way using Falcon 460 EC, treated with fertiliser and fungicide at the same time, or left as control specimens with no measures taken. All preparations were applied by means of foliar spraying 5 times in the course of the season. Survival of seedlings was then assessed at the season end, along with biometric features like root−collar diameter, length of main root and stem, dry mass of leaves and stem, and degree of oak powdery mildew attack. Results indicated curtailment of mildew infection of oak seedlings thanks to both of the biostimulators, albeit to a more limited extent than when fungicide was applied. No stimulation of seedling growth was achieved, however, though the most favourable biometric parameters characterised the oaks supplied with both biostimulator and fungicide. Significantly higher survival rate was noted for oaks offered effective protection against mildew, in the variants with the fungicide or with simultaneous application of Apol−Humus or Apol−Hum Chelat with Falcon. The research points to the two biostimulators under study (based on natural components) being suitable for use in the nursery production of pedunculate oak seedlings, with it being presumed that either or both can allow for reduction in amount of fungicide necessary to be used to safeguard seedlings against mildew.
Źródło:
Sylwan; 2020, 164, 04; 292-299
0039-7660
Pojawia się w:
Sylwan
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Sposoby indukowania mutacji a zmiennosc kwasow tluszczowych jedno- i wielonienasyconych w nasionach rzepaku ozimego
Autorzy:
Spasibionek, S
Powiązania:
https://bibliotekanauki.pl/articles/833048.pdf
Data publikacji:
2005
Wydawca:
Instytut Hodowli i Aklimatyzacji Roślin
Tematy:
kwas oleinowy
mutageneza chemiczna
nasiona
kwasy tluszczowe
Brassica napus
kwas linolenowy
kwas linolowy
rzepak ozimy
oleic acid
chemical mutagenesis
seed
fatty acid
linolenic acid
linoleic acid
winter rape
Źródło:
Rośliny Oleiste - Oilseed Crops; 2005, 26, 1; 35-49
1233-8273
Pojawia się w:
Rośliny Oleiste - Oilseed Crops
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Właściwości farmakologiczne nowych inhibitorów wychwytu zwrotnego gaba u myszy
Pharmacological Activity of Novel Gaba Re-Uptake Inhibitors in Mice
Autorzy:
PODKOWA, Adrian
GRZYWA, Anna
LECHOCKA, Anna
SZLONZAK, Agata
KOWALCZYK, Paula
KULIG, Katarzyna
FILIPEK, Barbara
SAŁAT, Kinga
Powiązania:
https://bibliotekanauki.pl/articles/1033735.pdf
Data publikacji:
2014
Wydawca:
Zakład Opieki Zdrowotnej Ośrodek Umea Shinoda-Kuracejo
Tematy:
GABA transporters
depression
pain
tiagabine
γ-aminobutyric acid
γ-hydroxybutyric acid
Opis:
Γ-aminobutyric acid (GABA) is a widely distributed neurotransmitter in the mammalian central nerv-ous system. The GABAergic neurotransmission is involved in numerous processes, including neuronal excitability and mood disorders. GABA is removed from the synaptic cleft by specific proteins called plasma membrane GABA transporters. In the present work we focus on antinociceptive and antidepres-sant-like properties of four new GABA re-uptake inhibitors. These compounds are N-benzylamide derivatives of GABA. We also investigate their impact on animal’ locomotor activity and motor coordina-tion. All the examined compounds present analgesic activity in the hot plate test. Most of them also demonstrate antidepressant-like properties in the forced swim test in mice. Similarly to tiagabine, the test compounds significantly affect locomotor activity and some of them cause motor coordination impair-ments. The obtained results suggest that compounds targeting at GABA transporters may exert analgesic and antidepressant-like properties.
Źródło:
Medicina Internacia Revuo; 2014, 26, 102; 32- 41
0465-5435
Pojawia się w:
Medicina Internacia Revuo
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Zmniejszenie szybkości reakcji dla zwiększenia efektywności zabiegów kwasowania złóż węglanowych o wysokiej temperaturze
Reaction rate decrease as a key to successful acidizing treatment in high temperature carbonate reservoirs
Autorzy:
Kasza, P.
Powiązania:
https://bibliotekanauki.pl/articles/300021.pdf
Data publikacji:
2007
Wydawca:
Akademia Górniczo-Hutnicza im. Stanisława Staszica w Krakowie. Wydawnictwo AGH
Tematy:
kwasowanie
złoże węglanowe
emulsja ropno-kwasowa
acid
carbonate reservoirs
emulsified acid
Opis:
W artykule przedstawiono wyniki badań laboratoryjnych nad zastosowaniem emulsji ropno-kwasowej do zabiegów kwasowania matrycowego w złożach węglanowych o wysokiej temperaturze. Badania były prowadzone pod kątem wykorzystania tej technologii do intensyfikacji wydobycia odwiertów złoża BMB. Po zakończeniu badań wykonano zabieg pilotażowy. Po potwierdzeniu pozytywnych rezultatów, technologia kwasowania matrycowego emulsją ropno-kwasową została wdrożona do stosowania w odwiertach złoża BMB. W wyniku wykonanych zabiegów uzyskano wzrost wydobycia ropy i gazu oraz ograniczenie ciśnienia różnicowego.
Laboratory research of use emulsified acid for matrix acidizing treatment in high temperature carbonate reservoirs was presented in this paper. The main goal of this research was introduce this technology to use in stimulation wells of BMB oil field. After the research a pilot treatment has been done. After obtaining positive results from this treatment, this technology has been used for stimulating BMB oil and gas wells. Oil and gas production increase and differential pressure drop were observed after acidizing operations.
Źródło:
Wiertnictwo, Nafta, Gaz; 2007, 24, 1; 263-268
1507-0042
Pojawia się w:
Wiertnictwo, Nafta, Gaz
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Bioługowanie metali ciężkich z odpadów pogalwanicznych przy neutralnym pH środowiska, w obecności bakterii produkujących biosurfaktanty
Bioleaching of heavy metals from galvanic wastes at neutral pH in the presence of biosurfactant producing bacteria
Autorzy:
Karwowska, E.
Andrzejewska-Morzuch, D
Powiązania:
https://bibliotekanauki.pl/articles/1819284.pdf
Data publikacji:
2012
Wydawca:
Politechnika Koszalińska. Wydawnictwo Uczelniane
Tematy:
microbial surfactants
sludge
extraction
acid
Opis:
Precipitates and sludges from the galvanic industry are one of the sources of the environment contamination with heavy metals. Therefore, the investigations are carried out in order to developer the effective method of metals elimination from these wastes. The promising results are obtained in case of the application of microbial leaching. Up to now results concerned mainly the metals bioleaching in acidic environment. In this research work the possibility of heavy metals removal from galvanic wastes using the culture of sulphur oxidizing bacteria (pH 2-4) and a mixed culture of both sulphur oxidizing bacteria and biosurfactant producing bacteria (pH 6.5-8) was examined. It allowed to compare the process effectiveness in acidic and neutral environment. The cultures were prepared based on the activated sludge from the municipal wastewater treatment plant. The presence of sulphur oxidizing bacteria Acidithiobacillus ferrooxidans was confirmed using the PCR method. Bacillus subtilis and B. cereus strains were applied as biosurfactant producers. Three galvanic wastes, different in grain size, water content and heavy metal concentration, were bioleached. The research revealed that the metal release from galvanic wastes was more effective in presence of biosurfactant, especially in case of copper, but also for cadmium and chromium. The process effectiveness in acidic condition was comparatively lower. Zinc was the only metal that was bioleached faster in acidic environment, with similar final metal removal after 25 days of the process. The maximum values of metals elimination in the presence of biosurfactant depended on the bioleached waste type and were: 7.1-100% for copper, 3.7-50.3% for zinc, 30-50.5% for chromium, 34.1-71.9% for cadmium. The effectiveness of the nickel and lead removal was lower than 5%. The prolongation of the bioleaching period up to 40 days in case of waste C (the less susceptible to the bioleaching) resulted in elimination of 67.9% of Cu, 34.7% of Zn, 100% of Cr and 39.1% of Pb, while the effectiveness of nickel removal was still very low.
Źródło:
Rocznik Ochrona Środowiska; 2012, Tom 14; 597-606
1506-218X
Pojawia się w:
Rocznik Ochrona Środowiska
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Mutanty rzepaku ozimego podwojnie ulepszonego o zmienionym skladzie kwasow tluszczowych.
Autorzy:
Spasibionek, S
Byczynska, B.
Krzymanski, J.
Powiązania:
https://bibliotekanauki.pl/articles/833704.pdf
Data publikacji:
2000
Wydawca:
Instytut Hodowli i Aklimatyzacji Roślin
Tematy:
mutanty
kwas oleinowy
kwasy tluszczowe
kwas linolenowy
kwas linolowy
rzepak dwuzerowy
EMS
rzepak ozimy
desaturaza
mutant
oleic acid
fatty acid
linolenic acid
linoleic acid
double-improved cultivar
rape
ethyl methanesulphonate
desaturase
Źródło:
Rośliny Oleiste - Oilseed Crops; 2000, 21, 3; 715-724
1233-8273
Pojawia się w:
Rośliny Oleiste - Oilseed Crops
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Charakterystyka folianów i procesy kształtujące zawartość folianów i kwasu foliowego w produktach roślinnych i zwierzęcych oraz ich znaczenie w żywieniu człowieka
Characteristics of folates and processes that shape the content of folates and folic acid in plant and animal products and their importance in human nutrition
Autorzy:
Borucki, Maciej
Dziedziński, Marcin
Kobus-Cisowska, Joanna
Powiązania:
https://bibliotekanauki.pl/articles/26731636.pdf
Data publikacji:
2023-11-22
Wydawca:
Centrum Doradztwa Rolniczego w Brwinowie. Oddział w Poznaniu
Tematy:
kwas foliowy
foliany
źródła kwasu foliowego
znaczenie kwasu foliowego
biodostępność kwasu foliowego
folic acid
folates
sources of folic acid
importance of folic acid
bioavailability of folic acid
Opis:
Kwas foliowy odgrywa kluczową rolę w cyklu metylacji oraz biosyntezie DNA. Niedobór folianów w diecie może prowadzić do wielu zaburzeń tj. niedokrwistości czy zmniejszenia biosyntezy komórek w szpiku kostnym. Wskazuje się na niedobory kwasu foliowego w znacznej części liczby ludności w krajach rozwiniętych, nawet tam, gdzie występuje suplementacja żywności kwasem foliowym, tym samym bardzo istotną kwestią jest świadomość biodostępności i retencji kwasu foliowego w żywności. Mimo tego, że foliany występuje w wielu surowcach, jego biodostępność i zawartość w produktach gotowych do spożycia jest zależna od wielu czynników i wpływa na efekt odżywienia. Niniejszy artykuł jest opracowaniem wskazującym na kluczowe źródła folianów, jego biodostępność, rolę w organizmie człowieka, a także skutki niedoboru.
Folic acid plays a key role in the methylation cycle and in DNA biosynthesis. A deficiency of folic acid in the diet can lead to many disorders, such as anemia or reduced biosynthesis of cells in the bone marrow. There is good evidence of folic acid deficiency in a large proportion of the population in developed countries, even where folate supplementation occurs, so it is very important to be aware of the bioavailability and retention of folic acid in food. Despite the fact that folic acid is present in many raw materials, its bioavailability and content in ready-to-eat products depends on many factors and affects the nutritional effect. This article is a study indicating the key sources of folic acid, its bioavailability, role in the human body, and the effects of deficiency.
Źródło:
Zagadnienia Doradztwa Rolniczego; 2023, 113, 3; 21-36
1232-3578
2719-8901
Pojawia się w:
Zagadnienia Doradztwa Rolniczego
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Ocena wystepujacych na rynku krajowych olejow rzepakowych pod wzgledem zmiennosci skladu kwasow tluszczowych
Autorzy:
Jerzewska, M
Ptasznik, S.
Powiązania:
https://bibliotekanauki.pl/articles/833930.pdf
Data publikacji:
2000
Wydawca:
Instytut Hodowli i Aklimatyzacji Roślin
Tematy:
sklad kwasow tluszczowych
kwasy tluszczowe
olej rzepakowy
fatty acid content
fatty acid
rapeseed oil
Źródło:
Rośliny Oleiste - Oilseed Crops; 2000, 21, 2; 557-568
1233-8273
Pojawia się w:
Rośliny Oleiste - Oilseed Crops
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Występowanie kwasów tłuszczowych i steroli w środowisku naturalnym
The occurrence of fatty acids and sterols in the natural environment
Autorzy:
Łobos-Moysa, E.
Dudziak, M.
Powiązania:
https://bibliotekanauki.pl/articles/127453.pdf
Data publikacji:
2016
Wydawca:
Towarzystwo Chemii i Inżynierii Ekologicznej
Tematy:
środowisko naturalne
monitoring
kwas oleinowy
kwas linolowy
kwas palmitynowy
stigmasterol
β-sitosterol
betulina
environment
oleic acid
linoleic acid
palmitic acid
betulin
Opis:
Postęp w rozwoju technik analitycznych umożliwia obecnie oznaczanie bardzo dużej liczby zanieczyszczeń organicznych występujących w środowisku naturalnym. Część tych zanieczyszczeń jest pochodzenia naturalnego. Aktualnie badania ukierunkowane są głównie na zanieczyszczenia specyficzne, których obecność jest wynikiem antropogenicznego oddziaływania na środowisko naturalne. W celu oceny występowania specyficznych zanieczyszczeń i mikrozanieczyszczeń w środowisku naturalnym, tj. wybranych kwasów tłuszczowych nienasyconych - oleinowego i linolowego oraz kwasu nasyconego - palmitynowego, a także steroli stigmasterolu i β-sitosterolu oraz betuliny, opracowano techniki ich wydzielania i ich chromatograficznej analizy. Analizę jakościowo-ilościową zarówno kwasów tłuszczowych, jak i steroli wykonywano przy użyciu chromatografu GC / ion trap / MS (model Saturn 2100 T firmy Varian) wyposażonego w kolumnę chromatograficzną VF-5ms (Varian). Do wydzielania związków zastosowano różne techniki ekstrakcji. W przedstawionych w pracy badaniach prowadzono monitoring występowania zanieczyszczeń w wodach powierzchniowych Górnego Śląska (Wójtowianka (Doa), Potok Rokitnicki, rzeka Bytomka, rzeka Kłodnica i Kanał Gliwicki) w okresie od stycznia do czerwca 2015 roku.
Nowadays, advances in the analytical techniques allow the determination of hundreds of organic pollutants present in the environment. Some of organic pollutants are of natural origin. Although the current study are mainly aimed at specific pollution, the presence of which is the result of anthropogenic impacts on the environment. In order to assess the appearance of specific pollutants and micropollutants in the environment ie the selected unsaturated fatty acids: oleic, linoleic, saturated acid: palmitic and sterols: stigmasterol, β-sitosterol and betulin, the techniques for their isolation and analysis have been developed. Quality and quantity analysis of fatty acids and sterols was carried out using GC/ion trap/MS chromatographic system (model Saturn 2100 T, Varian) equipped with a chromatography column VF-5ms (Varian). Various extraction techniques have been used for isolation of the pollutants. In this study the monitoring of level of contamination in surface water of Upper Silesia (Wójtowianka (Doa) Stream, Rokitnica Stream, Bytomka River, Klodnica River and Gliwice Channel) was conducted in the period from January to June in the 2015.
Źródło:
Proceedings of ECOpole; 2016, 10, 1; 209-217
1898-617X
2084-4557
Pojawia się w:
Proceedings of ECOpole
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Znaczenie kwasu foliowego dla zdrowia organizmu człowieka
The importance of folic acid for the health of the human body
Autorzy:
Banyś, Karolina J.
Knopczyk, Monika W.
Bobrowska-Korczak, Barbara
Powiązania:
https://bibliotekanauki.pl/articles/762697.pdf
Data publikacji:
2020-03-15
Wydawca:
Polskie Towarzystwo Farmaceutyczne
Tematy:
kwas foliowy
MTHFR
niedobór
mutacja
aktywny kwas foliowy
folic acid
mutation
deficiency
active folic acid
Opis:
A well-balanced diet is undoubtedly a key factor to maintain your body's normal state of health. A deficiency or excess of any nutrient can cause negative effects on human health. Folic acid is one of the elements of the diet, which is often supplied in insufficient quantities. This vitamin and its derivatives participate in the metabolism of amino acids and nucleic acids. Therefore, it is necessary for the proper functioning of the body's cells and for maintaining homeostasis, especially of the nervous, circulatory and cardiovascular systems. The biological activity of folic acid and its derivatives essentially affects the metabolism of important amino acids, such as methionine, homocysteine, serine, glycine, pyrimidine and purine synthesis and DNA methylation. The synthetic form of folic acid (most oxidized), which can be found in fortified foods, dietary supplements or pharmaceuticals, does not show biological activity. It is transformed in a series of reactions with the participation of many enzymes to form folates, which differ in the number of glutamic acid residues and the degree of oxidation. The actively biological form is reduced folate (L-5-MTHF), which is transported together with the blood to cells where it undergoes biological processes important for our health. The MTHFR gene, coding for the enzyme protein of the same name - methylene tetrahydrofolate reductase, is located on chromosome 1 at the 1p36.3 locus. This protein is responsible for the catalysis of the enzymatic reaction, which is the reduction of 5,10-methylenetetrahydrofolate to L-5-methyltetrahydrofolate, i.e. the active form of folate. This form is necessary in the process of homocysteine degradation, in the aftermath remethylation to methionine. This protein is responsible for the catalysis of the enzymatic reaction, which is the reduction of 5,10-methylenetetrahydrofolate to L-5-methyltetrahydrofolate, i.e. the active form of folate. This form is necessary in the process of homocysteine degradation, in the aftermath remethylation to methionine. However, according to available literature, mutation of the MTHFR 677C> T gene occurs in even 53% of the population. Among carriers of the TT genotype, it can cause about 70% reduction of MTHFR reductase activity. It is especially dangerous for people who do not provide adequate amounts of folic acid along with their diet and for those who need a high amount of this vitamin, e.g. due to taking medications that reduce its absorption, i.e. metformin or oral contraceptives. Many people metabolize folic acid on insufficient levels. For medical reasons, not the mutation itself is a problem, but too low the folate levels. In recent years, there is more and more discussion about the active form of folic acid and the possibility of effective supplementation with metapholine, which is a combination of calcium with L-5-MTHFR. It is a natural and reduced form of folate, which hydrolized and then transforms into L-5-MTHFR. Metapholine, in comparison to folic acid, is not reduced to be incorporated into metabolic processes in the cell, which is catalyzed by DHFR and MTHFR enzymes. In addition, the absorption of the active form of folic acid is faster because some metabolic pathways are missed. This is particularly important for people who have a MTHFR gene mutation homozygous with 665C> T and / or 1298A> C polymorphism and a mutation of the DHFR gene with 458A> T polymorphism. Numerous clinical studies have confirmed the efficacy and safety of the active form of folic acid. In a study by Houghton et al., which was conducted among pregnant Canadian women, L-5-MTHFR was shown to be at least as effective in lowering homocysteine levels as folic acid supplementation. In addition, the active form of folic acid was more effective at storing folate in erythrocytes. In a study conducted by Lamers et al. on 135 women after a period of 24 weeks, L-5MTHR was shown to be a suitable alternative in reducing plasma homocysteine levels compared to folic acid and placebo. In addition, Bentley et al. analyzed the results of 112 pregnant women from the USA. Patients were assigned to two groups in which each took vitamin B12. In addition, in one of them women supplemented with L-5-MTHFR, and in the other - folic acid. The results showed that patients who supplemented the active form of folic acid not only had higher hemoglobin levels, but also less often had anemia. When analyzing clinical trials of patients with the MTHFR mutation, the same trend was observed. Metafoline increased plasma folate levels and decreased homocysteine levels. In one study on German women, there was a decrease in homocysteine levels and an increase in folate levels in both plasma and red blood cells in patients who supplemented the active form of folic acid. In another study involving Swiss patients with the current 677CC MTHFR or 677TT MTHFR mutation, it was demonstrated that using L-5-MTHFR significantly reduces homocysteine levels compared to folic acid. It is also worth mentioning that Prinz-Langenhol et al. in a study on women with the 677CC and 677TT mutations proved that the active form of folic acid has a better effect on increasing folate levels than folate. It is also worth mentioning that folic acid at high doses can mask ailments or even diseases caused by vitamin B12 deficiency. In addition, folic acid administered at high doses in patients with the MTHFR mutation is not reduced to an oxidized, inactive form and is not properly transported to plasma. Non-metabolised folic acid can be dangerous to the human body and contribute to the development of cancer. Supplementation, in particular the active form of folic acid, should be considered by patients who are carriers of the MTHFR or DHFR mutation. In addition, the use of stimulants such as alcohol or nicotine also negatively affects the absorption of this vitamin. Taking some medications weakens the absorption of folic acid - these include folic acid antagonists, anti-tuberculosis drugs, hormonal oral contraceptives, nonsteroidal anti-inflammatory drugs or metformin widely used. Folic acid is necessary for the proper functioning of the human body and its deficiency may induce various disease processes in the body, which include: the formation of neural tube defects, disorders in the nervous system, megaloblastic anemia, a negative effect on the functioning of the cardiovascular system and the development of atherosclerosis and cancer. More and more people have anemia, including megaloblastic anemia, which is characterized by abnormal nucleic acid synthesis. The consequence of too low folate levels is impaired red blood cell production, an increase in their volume, and premature death. Extremely dangerous is megaloblastic anemia, the so-called malignant anemia in pregnant women, as it can lead to serious complications such as hemorrhage, infection, and even intrauterine fetal death. A significant influence of folic acid on the functioning of the nervous system has been proven in many clinical studies. This vitamin is involved in the formation of important neurotransmitters such as: adrenaline, dopamine and noradrenaline, therefore its deficiency may lead to the development of neuropsychiatric disorders (dementia, epilepsy, depression and psychosis). These disorders are often caused by high levels of homocysteine, which is not properly metabolized to methionine due to folate deficiency. An excess of homocysteine, as a consequence, leads to atherosclerosis in the cerebral arteries and, as a result of insufficient blood supply, transient ischaemic attack occur, which can contribute to the development of dementia or Alzheimer's disease. Nutritional observations indicate that eating fresh vegetables rich in folic acid protects against the formation of some cancers, e.g. large intestine, breast, ovary, uterus, lungs, pancreas. Deficiency of folic acid promotes the activation of protooncogenes to oncogenes, which in consequence results in a decrease in the stability of cellular DNA. A study carried out by Giovannicci et al. showed that excessive alcohol consumption and folic acid deficiency associated with it increased the risk of developing colorectal cancer by almost four times. However, what cannot be overlooked, the results of clinical trials show us that very high doses and folic acid accumulation favor the development of some cancers. It is thought that excess of folic acid may lead to hypermethylation of DNA and, consequently, to inactivation of the suppressor genes responsible for controlling cell division. Women in the pre-contraceptive period, during pregnancy and breastfeeding are included in the group of people with a special need for folic acid, in whom deficiency can cause many negative effects. The presence of folic acid is necessary in the process of cell formation and growth in the developing fetus, especially when the neural tube is forming. Moreover adequate folic acid concentration decreases risk of fetal heart and urinary tract defects, and also reduces the occurrence of thrombosis and miscarriage in pregnant women. Steeweg-de Graaff J. et al. conducted evaluation of emotional and behavioral development at the age of 3 depending on the concentration of folates and homocysteine in the mother's blood plasma at an early stage of the pregnancy. It was noted that with insufficient folate supply, associated with a lack of or its late supplementation increases the risk of emotional problems in children. In addition, defects of the nervous system may occur as a result of dysfunction of folate metabolism. In its transformation pathway MTHFR reductase takes a particular role. Its reduced activity contributes to the impairment of folic acid metabolism, and the MTHFR gene - type 677CC is considered a risk factor for the development of neural tube defects. Randomized study compared pharmacokinetic parameters of [6S]-5-MTHF and folic acid in healthy women of childbearing age with different MTHFR genotypes (677TT n = 6, 677CC n = 8). Higher peak folate concentrations in plasma with [6S]-5-MTHF supplementation was found, in comparison with folic acid and not depending in the MTHFR genotype, as well as a shorter time needed to reach maximum concentration. In a different randomized, double-blind trial significantly higher folate levels in red blood cells were obtained in women receiving [6S]-5-MTHF. Studies confirm the hypothesis that nutritional deficiencies are of great importance in terms of fetal development. The results testify the need of folic acid supplementation, in which it is worth to consider the use of biologically active form, 12 weeks before planned pregnancy. In the second and third trimesters, the supplementation of folic acid is an important element in prevention of anemia caused by vitamin B12 and folic acid deficiency, i.e. megaloblastic anemia. Moreover, it was found that folic acid at a daily dose of 400 - 800 μg reduce the risk of fetal neural tube defects. In its guidelines, Polish Society of Gynecologists and Obstetricians (PTGiP) recommends supplementation of 400 μg / day of folic acid in women in low risk group in the pre-contraceptive period, pregnancy and during breastfeeding and supplementation of 800 μg/ day of folic acid in women in intermediate risk group and also high risk group in II and III trimester and during breastfeeding. It is worth emphasising that in most recent guidelines, PTGiP pays attention to the problem of folic acid metabolism and emphasizes the appropriateness of supplementation with its active form, especially at high doses. In folic acid metabolism, MTHFR catalyzes the synthesis to the active form of folate (L-5-MTHFR). It is necessary in the process of homocysteine degradation following remethylation to methionine. Unfortunately, as a result of inappropriate methylation, e.g. as a result of active form of folic acid deficiency, the concentration of homocysteine in the blood serum increases, which is responsible for various pathogenic processes in the body. Insufficient supply and improper metabolism of folic acid, as well as vitamins B6, B12 deficiency may be factors favorable for development of atherosclerosis and other diseases related to the cardiovascular system (e.g. heart attack, stroke, coronary artery disease). Excessively high concentration of homocysteine in the blood plasma, caused by disorders of its metabolic pathway in the body, is one of the reasons for the formation of atherosclerotic changes in blood vessels. Excess of homocysteine, with a simultaneous deficiency of folate and vitamin B12, damages the endothelium of blood vessels and increases oxidation processes, which are associated with the development of inflammation, oxidation of LDL cholesterol and change in the structure of the walls of blood vessels. In addition, the risk of developing peripheral thrombosis and hypertension increases. In the meta-analysis of Linda L. et al. it was found that high concentration of homocysteine is an independent factor of developing coronary heart disease. In the majority of studies, the risk of this disease is increased by 20% to 50% with every increase of concentration of homocysteine by 5 μmol /L in the blood of the examined persons. To ensure proper functioning of blood vessels and to reduce the risk of cardiovascular disease, one needs to provide adequate concentration of homocysteine in the body. Folates and their adequate supply with diet or supplementation play a key role in this process. Looking at the numerous clinical studies, available literature and the function of folic acid, it can be stated that it is an essential compound with multidirectional biological action, which is involved in the synthesis of amino acids and nucleic acids important for health. It plays an important role in tissues, such as: the fetus, hematopoietic system and gastrointestinal epithelium, in which cell divisions occur. For this reason, the presence of folic acid in the right amounts, ensures the proper functioning of our body. A deficiency of folic acid in the diet leads to a reduced concentration of folate in plasma and red blood cells. It is a condition that contributes to the formation of many serious diseases in our body and congenital neural tube defects in the fetus. As clinical studies have shown, the optimal concentration of folates in the blood reduces the risk of cardiovascular, circulatory, central nervous system diseases and certain types of cancer. To reduce the risk of diet-related diseases caused by folic acid deficiency, daily diet should be optimally balanced and contain products rich in natural folates. If diet is an insufficient source of folic acid, its supplementation should be considered, with the possible inclusion of its active form. Supplementation is recommended, in particular, for people with: megaloblastic anemia, diabetes mellitus, malabsorptions (e.g. Crohn's disease), alcoholism, malnutrition, neurodegenerative diseases (e.g. Alzheimer's disease), cardiovascular diseases, elevated homocysteine levels and using certain medications (e.g. oral contraceptives, metformin, methotrexate). It is also worth mentioning that metapholine supplementation bypasses the multistage metabolic process before incorporating folates into the cell cycle, as opposed to the inactive form of folic acid. This is particularly important for patients with the DHFR and MTHFR mutation, which depending on the polymorphism, may occur in up to 53% of the Caucasian population. Consequently, MTHFR reductase activity is reduced by up to 70%.
Kwas foliowy jest niezbędny do właściwego funkcjonowania organizmu i zachowania homeostazy. Uczestniczy w metabolizmie kwasów nukleinowych, aminokwasów, syntezie pirymidyn i puryn. Syntetyczna postać kwasu foliowego nie wykazuje aktywności biologicznej. Przekształcana jest w szeregu reakcji do postaci folianów (L-5-MTHF) które, są transportowane do komórek, gdzie bierze udział w ważnych procesach biologicznych. Gen MTHFR odpowiedzialny jest za katalizę reakcji enzymatycznej: redukcję 5,10-metylenotetrahydrofolianu do aktywnej formy. Mutacja genu MTHFR 677C>T występuje nawet u 53% populacji czego konsekwencją jest zmniejszenie aktywności reduktazy – MTHFR nawet o 70%. Metafolina (aktywna forma) w przeciwieństwie do kwasu foliowego, aby zostać włączona do procesów metabolicznych w komórce, nie ulega redukcji, katalizowanej przez DHFR oraz MTHFR. Jest to istotne w szczególności dla osób, które mają mutację genu MTHFR oraz DHFR. Przyjmowanie niektórych leków osłabia wchłanialność kwasu foliowego. Kwas foliowy jest niezbędny do prawidłowego funkcjonowania organizmu człowieka a jego niedobór może indukować różne procesy chorobowe w organizmie, do których zaliczamy: powstawanie wad cewy nerwowej, zaburzenia w układzie nerwowym, niedokrwistość megaloblastyczną, negatywny wpływ na funkcjonowanie układu sercowo – naczyniowego oraz rozwój miażdżycy i nowotworów. Witamina ta bierze udział w powstawaniu ważnych neuroprzekaźników, takich jak: adrenalina, dopamina i noradrenalina, dlatego jej niedobór może prowadzić do powstania zaburzeń neuropsychiatrycznych. Niedobór kwasu foliowego sprzyja aktywacji protoonkogenów do onkogenów. Liczne badania kliniczne i dostępna literatura potwierdzają funkcję kwasu foliowego, że jest to niezbędny związek o wielokierunkowym działaniu biologicznym, który pełni istotną rolę w tkankach. Suplementacja metafoliną omija wieloetapowy proces metaboliczny w przeciwieństwie do nieaktywnej postaci kwasu foliowego.
Źródło:
Farmacja Polska; 2020, 76, 2; 79-87
0014-8261
2544-8552
Pojawia się w:
Farmacja Polska
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Sklad i wlasciwosci przeciwrodnikowe fenolokwasow slodu
Autorzy:
Samotyja, U
Malecka, M
Klimczak, I
Powiązania:
https://bibliotekanauki.pl/articles/827512.pdf
Data publikacji:
2002
Wydawca:
Polskie Towarzystwo Technologów Żywności
Tematy:
jeczmien
wlasciwosci przeciwutleniajace
surowce roslinne
kwas ferulowy
slod
zwiazki fenolowe
kwas p-kumarowy
oznaczanie
kwas kawowy
kwas sinapinowy
kwasy fenolowe
barley
antioxidant property
plant raw material
ferulic acid
malt
phenolic compound
p-coumaric acid
determination
caffeic acid
sinapic acid
phenolic acid
Opis:
Kwasy fenolowe należą do istotnych składników roślinnych surowców żywnościowych ze względu na ich przeciwutleniające właściwości. W pracy oznaczono ogólną zawartość związków fenolowych oraz zidentyfikowano i dokonano ilościowej analizy następujących fenolokwasów: ferulowego, kawowego, sinapinowego i p-kumarowego w słodzie wyprodukowanym z dwóch odmian jęczmienia. W największych ilościach występował kwas ferulowy. Ponad 90% kwasów fenolowych występowało w postaci związanej. Dokonano również oceny właściwości przeciwrodnikowych kwasów fenolowych zidentyfikowanych w słodzie. Największą aktywność przeciwrodnikową w teście z DPPH' wykazał kwas sinapinowy.
Phenolic acids are interesting constituents of foodstuff of plant origin due to their antioxidant activity. Total phenolic compounds were determined and four phenolic acids (ferulic, caffeic, sinapic and p - coumaric) were identified and quantified in malt from two barley varieties. Ferulic acid has been identified as the most important quantitatively. Insoluble bound phenolic acids covered over 90% of total phenolic acids content. The antiradical efficiency of phenolic acids of malt was investigated using method based on the reaction with DPPH·. Sinapic acid appeared as the most effective radical scavenger.
Źródło:
Żywność Nauka Technologia Jakość; 2002, 09, 3; 67-76
1425-6959
Pojawia się w:
Żywność Nauka Technologia Jakość
Dostawca treści:
Biblioteka Nauki
Artykuł
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