Wyniki wyszukiwania - Biblioteka Nauki

1

In silico studies of selected xanthophylls as potential candidates against SARS-CoV-2 targeting main protease (Mpro) and papain-like protease (PLpro)

100%

Karpinski T. M. , Kwasniewski M. , Ozarowski M. , Alam R.

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nr 2

2

The effect of irradiance on the xanthophyll composition of Skeletonema marinoi (Bacillariophycae), Teleaulax sp., Rhodomonas sp. (Cryptophyceae), and Heterocapsa triquetra (Dinophyceae)

84%

Lotocka M.

Oceanological and Hydrobiological Studies

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2015

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tom 44

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nr 2

3

Whole-plant acclimation to photooxidative stress: from photoprotection to leaf growth and root architecture

84%

Alter P. , Caliandro R. , Luo F. , Kastenholz B. , Kerstin N. , Matsubara S.

BioTechnologia. Journal of Biotechnology Computational Biology and Bionanotechnology

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2013

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tom 94

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nr 2

4

The effect of biochanin A on the chlorophylls and carotenoids content in the alga Chlorella vulgaris Beijerinck

84%

Czerpak R. , Piotrowska A. , Dobrzyn P. , Tatur A. , Marczuk M.

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nr 3

5

Adaptation of the photosynthetic apparatus of Nitellopsis obtusa to changing light intensity at the molecular level: different pathways of a singlet excitation quenching

67%

Gruszecki W. I. , Gospodarek M. , Jaskowska A. , Spiewla E.

Acta Physiologiae Plantarum

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2006

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tom 28

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nr 2

EN

The effect of pro longed illumination (60 min) with photosynthetically active monochromatic radiation of low intensity (3 μmol-m⁻² ·s⁻¹) and high intensity (60 mmol m⁻² ·s⁻¹), corresponding to the physiological conditions and light stress conditions, respectively, was studied in the algae Nitellopsis obtusa. Illumination of Nitellopsis obtusa cells with strong light was associated with activation of the xanthophyll cycle, manifested by the deepoxidation of violaxanthin and accumulation of antheraxanthin and zeaxanthin. At the same time, the efficient singlet excitation quenching in the photosynthetic apparatus was activated, as demonstrated by the decrease in the intensity of the chlorophyll a fluorescence emission by ca 50 %. The difference of the fluorescence excitation spectra recorded before and after the light treatment match the difference absorption spectrum of the xanthophyll cycle pigments. The illumination with low light intensity resulted also in the chlorophyll a fluorescence quenching but the effect was very small (less than 10 %). The fluorescence quenching is interpreted in terms of the energy transfer between the Qy energy level of chlorophyll a and the 2¹Ag⁻ energy level of zeaxanthin. The singlet energy levels of carotenoids, corresponding to the green spectral region, are also taken into consideration in the interpretation of the excitation energy exchange between the carotenoids and chlorophylls. Possible molecular mechanisms involved in the activation of the strong and the weak excitation quenching, including violaxanthin isomerization, and possible physiological functions of such pathways of energy transfer are discussed.

6

The stimulative effect of hydrocortisone on photosynthetic pigments in the green alga Chlorella vulgaris Beijerinck

67%

Czerpak R. , Bajguz A. , Kalinowska J.

International Journal of Ecohydrology and Hydrobiology

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2001

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tom 01

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nr 4

EN

Studies carried out on the alga Chlorella vulgaris (Chlorophyceae) showed that hydrocortisone applied in a concentration range of 10-4 - 10-5 M has a stimulating effect on its growth, i.e. the content of fresh and dry mass, and on the chlorophyll and carotenoid contents. Hydrocortisone was found to have its greatest stimulative effect on the biochemical parameters analysed in a concentration of 5x10-5 M between the 15th and 20th day of the alga culture (with the exception of monoxy-xanthophylls). The strongest stimulation was noted in the content of: chlorophylls (a+b), from 184 % - 200 %, the total carotenoid pool, 170% - 190%, including carotenes stimulated from 193 % to 208 %, xanthophylls with 2 oxygen atoms in he molecule 171 % - 191 %, and richly oxidated xanthophylls 146 % -187 %. Maximum stimulation of the dry mass content was within the range of 138 % -151 % whereas the weakest stimulation was noted in the monoxy-xanthophylls 121 % - 125 % as compared with the control (100 %).The studies showed that hydrocortisone, as a typical representative of animal glucocorticoids, also occurring in some species of vascular plants and probably in thallophytes, when applied in the optimum concentration range 10-4 - 10-6 has a fairly intensive stimulative effect on the growth of C. vulgaris cells and their content of photosynthetic pigments, i.e. chlorophylls (a+b) and carotenoids especially carotenes and xanthophylls moderately rich in oxygen.

7

Wplyw dolistnego stosowania jonow Ca2plus oraz procesu suszenia na zawartosc alfa-tokoferolu, beta-karotenu i ksantofili w owocach papryki slodkiej

51%

Perucka I. , Materska M.

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nr 4

117-125

PL

Określono wpływ jonów wapniowych (stosowanych dolistnie) oraz procesu suszenia na zawartość witamin przeciwutleniających: tokoferoli (wit. E), β-karotenu (prowitaminy A) i ksantofili w owocach papryki słodkiej. Badaniom poddano dwie odmiany papryki: King Arthur i Red Knight. W fazie 4–5 liści sadzonki pryskano roztworem CaCl2, po czym wysadzano je do gruntu. Próbę kontrolną stanowiły rośliny bez oprysku. Do analiz chemicznych pobierano owoce w pełni dojrzałe. Po usunięciu gniazd nasiennych z owocni przygotowywano ekstrakty. Frakcje tokoferoli, β karotenu i ksantofili izolowano za pomocą metod chromatograficznych, a zawartość poszczególnych składników oznaczano spektrofotometrycznie. Na podstawie wyników badań stwierdzono, że owoce roślin kontrolnych odmiany Red Knight charakteryzowały się ponad dwukrotnie wyższą zawartością α-tokoferolu i β-karotenu oraz o 60% wyższą zawartością ksantofili niż owoce odmiany King Arthur. Proces suszenia papryki spowodował 70–78% spadek zawartości α-tokoferolu oraz 12–46% zmniejszenie zawartości β-karotenu w owocach obu odmian. Natomiast zawartość ksantofili zwiększyła się o 22% zarówno w owocach odmiany King Arthur, jak i Red Knight. Podczas suszenia papryki, pochodzącej z roślin poddanych opryskowi, nie odnotowano korzystnego wpływu jonów Ca2+ na trwałość zawartego w owocach α-tokoferolu. Pod względem zawartości β-karotenu, zmniejszenie strat tego składnika stwierdzono jedynie w owocach odmiany Red Knight – z 46 do 15%. Suszenie papryki odmiany King Arthur spowodowało zaś powiększenie straty β-karotenu z 12 do 14%. Jony Ca2+ wpłynęły korzystnie na zawartość ksantofili w świeżych owocach obu odmian, natomiast suszenie sprzyjało wzrostowi zawartości tych składników (o 30%) w papryce odmiany King Arthur.

EN

In this study it was determined the impact of both the Ca2+ ions (applied on the leaves) and drying process on the content of antioxidant vitamins: tocopherols (vitamin E), β-carotene (pro-vitamin A), and xanthophylls in the fruits of sweet pepper. Two pepper varieties (cultivars) were investigated: King Arthur and Red Knight. During the seedling phase with 4-5 leaves, the leaves were sprayed with a CaCl2 solution and planted in the soil. The control group were made of plants that were not treated using the CaCl2 solution. Only the fully raped fruits were used in the chemical analyses. Extracts were made of pure pericarps after the seed-bearing core was removed. The fractions of α-tocopherol, β-carotene, and xanthophylls were isolated by a chromatographic method, and, then, contents of each component were determined using spectrophotometric methods. On the basis of the investigation results obtained, it was stated that the fruits of the control Red Knight plants had a content of α-tocopherol and β-carotene that was more than twice as high as in the King Arthur variety, and the contents of xanthophylls in Red Knights were by 60% higher if compared with their content in the King Arthur pepper fruits. The drying process, when applied to the pepper, caused a dramatic decrease (70% to 78%) in the concentration of α-tocopherol, while the β-carotene content decreased at a lower rate (from 12% to 46%). On the other hand, the content of Xanthophylls in the two cultivars (King Arthur and Red Arthur) was higher by 22%. While drying the peppers from the treated plants, there was stated no favourable impact of the Ca2+ ions on the stability of the α-tocopherol contained in their fruits. With regard to β-carotene, its losses were stated only in the Red Knight fruits, and they decreased from 46% to 15%. When the King Arthur pepper fruits were dried, this process caused the increase in the loss of β -carotene from 12% to 14%. The Ca2+ ions favourably influenced the content of xanthophylls in fresh fruits of the two cultivars, and the drying process was conducive to the increase in the content of these components (by 30%) in the King Arthur pepper.

8

Zawartosc karotenoidow w zielonkach i paszach konserwowanych

42%

Iwanska S. , Pysera B. , Strusinska D.

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1997

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tom 47

117-128