Wyniki wyszukiwania - Biblioteka Nauki

1

Spectroscopy analysis for simultaneous determination of lycopene and β-carotene in fungal biomass of Blakeslea trispora

100%

Soroka I. M. , Narushin V. G. , Turiyansky Y. D. , Tyurenkov A. A.

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nr 1

65-69

EN

Blakeslea trispora is a good alternative source for producing such carotenoids as lycopene and β-carotene. The objective of this research was to elaborate a method for the simultaneous determination of lycopene and β-carotene in Blakeslea trispora products using a usual UV-vis spectrophotometer. The standard solutions of the mixture of different concentrations of β-carotene and lycopene were measured with the UV-vis method and correlation formula for the extinction coefficients of 1% standard solution of lycopene in the solvent (hexane) and the ratios of the optical densities at the character peaks of 470 and 502 nm was elaborated. This gives a possibility to calculate the concentrations of lycopene and β-carotene in the mixture. The prediction quality of the UV-vis method was sufficient and the obtained results were very close to the ones, being measured with the HPLC technique. The proposed method can be used for both routine industrial work and academic research, providing the rapid analysis for simultaneous measurements of lycopene and β-carotene.

2

Synthesis of highly 13C enriched carotenoids: access to carotenoids enriched with 13C at any position and combination of positions

88%

Lugtenburg J. , Dawadi P. B. S.

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nr 1

11-16

EN

Carotenoids and their metabolites are essential factors for the maintenance of important life processes such as photosynthesis. Animals cannot synthesize carotenoids de novo, they must obtain them via their food. In order to make intensive animal husbandry possible and maintain human and animal health synthetic nature identical carotenoids are presently commercially available at the multi-tonnes scale per year. Synthetically accessible 13C enriched carotenoids are essential to apply isotope sensitive techniques to obtain information at the atomic level without perturbation about the role of carotenoids in photosynthesis, nutrition, vision, animal development, etc. Simple highly 13C enriched C1, C2 and C3 building blocks are commercially available via 99% 13CO. The synthetic routes for the preparation of the 13C enriched building blocks starting from the commercially available systems are discussed first. Then, how these building blocks are used for the synthesis of the various 13C enriched carotenoids and apocarotenoids are reviewed next. The synthetic Schemes that resulted in 13C enriched β-carotene, spheroidene, β-cryptoxanthin, canthaxanthin, astaxanthin, (3R,3'R)-zeaxanthin and (3R,3'R,6'R)-lutein are described. The Schemes that are reviewed can also be used to synthetically access any carotenoid and apocarotenoid in any 13C isotopically enriched form up to the unitarily enriched form.

3

Adverse effects of antioxidative vitamins

75%

Rutkowski M. , Grzegorczyk K.

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nr 2

105-121

EN

High doses of synthetic antioxidative vitamins: A, E, C and β-carotene are often used on long-term basis in numerous preventive and therapeutic medical applications. Instead of expected health effects, the use of those vitamins may however lead to cases of hypervitaminosis and even to intoxication. The article points out main principles of safety which are to be observed during supplementation with antioxidative vitamins. Toxic effects resulting from erroneous administration of high doses of those substances on organs and systems of the organism are also discussed. Attention is drawn to interactions of antioxidative vitamins with concomitantly used drugs, as well as intensification of adverse effects caused by various exogenous chemical factors. Moreover, the article presents the evaluation of supplementation with these vitamins, which was performed in large studies.

4

The role of well-known antioxidant vitamins in the prevention of cadmium-induced toxicity

75%

Sitek A. , Kozłowska L.

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nr 4

367-392

EN

Long-term exposure to cadmium (Cd) leads to the development of a number of conditions associated with liver and kidney damage, reproductive and cardiovascular disorders, in addition to visual impairment, blindness and hearing loss, among others. Cadmium has been classified as a human carcinogen by the International Agency for Research on Cancer. The toxicity of Cd is related to its pro-oxidant properties and the associated increase in oxidative stress. Antioxidant ingredients may be helpful in preventing the adverse effects of Cd. The effect of well-known antioxidant vitamins (E, C, A and β-carotene) in the prevention of Cd-induced toxicity is presented in this study. Numerous studies in animal models have shown that the effects of vitamins: E, C, A, and β-carotene were effective in reducing Cd concentrations in organs and tissues and reduced Cd-induced changes in liver, kidney, and reproductive, circulatory, nervous, immune, and respiratory systems. In contrast, the limited number of human studies does not allow to accurately determine the role of these nutrients in reducing Cd-induced toxicity, indicating the need for further studies clarifying the role of antioxidant vitamins in reducing Cd-induced toxicity. However, it seems reasonable to promote the consumption of natural food products that are sources of antioxidant vitamins in groups of people with occupational and environmental exposure to Cd.

5

Mikrobiologiczna produkcja karotenoidów

63%

Błaszczyk U. , Sroka P.

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tom T. 67, nr 5

32--35

PL

Karotenoidy to związki terpenowe o uznanym korzystnym oddziaływaniu na zdrowie człowieka, produkowane przez rośliny wyższe, a także mikroalgi, drożdże, grzyby strzępkowe oraz bakterie. Karotenoidy pochodzenia mikrobiologicznego są obiecującą alternatywą dla syntetycznych barwników. Kilka mikroorganizmów, takich jak Dunaliella salina, Blakeslea tri spora czy Haematococcus pluvialis, zostało zbadanych pod kątem produkcji karotenoidów na dużą skalę. Niektóre procesy i technologie z udziałem mikroorganizmów wdrożono z powodzeniem do produkcji przemysłowej.

EN

Carotenoids are terpenoid compounds with recognized beneficial effects on human health, which are synthesized de novo in higher plants, microalgae, yeasts, fungi and bacteria. Microbial carotenoids are a promising alternative to synthetic pigments. Several microorganisms such as Dunaliella salina, Blakeslea trispora or Haematococcus pluvialis have been investigated for large-scale production of carotenoids. Some microbial-based processes and technologies have been successfully implemented in industrial production of these pigments.