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1

Effects of organic compounds on the macroalgae culture ofAegagropila linnaei

100%

Messyasz B., Leska B., Fabrowska J., Pikosz M., Cieslak A., Schroeder G.

Open Chemistry

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2015

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vol. 13

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issue 1

EN

The effects of the impact of four organic compounds (ascorbic acid, biotin, glucose and sucrose) on ash, protein, fiber, fat and amino acid contents in the freshwater Aegagropila linnaei biomass were examined in 7 and 14 days of cultivations in high concentrations of tested compounds (100 mg L-1). The presence of examined organic compounds had a negligible effect on the development of algae and their biomass composition. There were no significant differences in the amino acids composition in the biomass in the presence of organic compounds compared to the test system. However, the increase in ash content was observed irrespective of the cultivation time in the case of all used organic compounds. Only slight differences in crude fat concentration were observed in the case of 7 days cultivation with ascorbic acid, biotin and sucrose, while the highest increase of ash content was observed after 14 days of supplementation with glucose. None of the compounds affected changes in amino acid content in the Aegagropila linnaei biomass. The results suggest that an environment enriched with the test organic compounds had only minimal, or at most short-term, effects on the algal biomass composition.

2

Protective action of vitamin C against DNA damage induced by selenium-cisplatin conjugate.

86%

Błasiak J., Kowalik J.

Acta Biochimica Polonica

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2001

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vol. 48

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issue 1

233-240

EN

Genotoxicity of anticancer drugs is of a special interest due to the risk of inducing secondary malignancies. Vitamin C (ascorbic acid) is a recognized antioxidant and, since human diet can be easily supplemented with vitamin C, it seems reasonable to check whether it can protect against DNA-damaging effects of antitumor drugs. In the present work the ability of vitamin C to modulate cytotoxic and genotoxic effects of a cisplatin analog, conjugate (NH3)2Pt(SeO3), in terms of cell viability, DNA damage and repair in human lymphocytes was examined using the trypan blue exclusion test and the alkaline comet assay, respectively. The conjugate evoked a concentration-dependent decrease in the cell viability, reaching nearly 50% at 250 μM. (NH3)2Pt(SeO3) at 1, 10 and 30 μM caused DNA strand breaks, measured as the increase in the comet tail moment of the lymphocytes. The treated cells were able to recover within a 30-min incubation in a drug-free medium at 37°C. Vitamin C at 10 and 50 μM diminished the extent of DNA damage evoked by (NH3)2Pt(SeO3) but had no effect on the kinetics of DNA repair. The vitamin did not directly inactivate the conjugate. Lymphocytes treated with endonuclease III, which recognises oxidised pyrimidines, displayed a greater tail moment than those untreated with the enzyme, suggesting that the damages induced by the drug have, at least in part, an oxidative origin. Vitamin C can be considered a potential protective agent against side effects of antitumor drugs, but further research with both normal and cancer cells are needed to clarify this point.

3

Size-dependent growth kinetics of vitamin C crystals in water solutions of L(+)-ascorbic acid with the addition of methanol and ethanol

86%

Wierzbowska B., Piotrowski K., Koralewska J., Matynia A.

Polish Journal of Chemical Technology

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2008

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vol. 10

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issue 1

60-65

EN

Growth kinetics of vitamin C crystals during the batch mass crystallization process in L(+)-ascorbic acid - methanol - ethanol - water system was determined. The linear growth rate values were estimated on the basis of the product crystal size distributions. The kinetic model of the continuous process in a MSMPR crystallizer was adopted for the batch mode description according to Nyvlt's conception, taking the sizedependent growth (SDG) rate effects into consideration. The kinetic parameter values were determined with a Rojkowski hyperbolic SDG model. A good compatibility between the experimental product crystal population density distributions and the SDG model predictions was observed. The interpretation of the kinetic data was presented and discussed.

4

Content of ascorbic acid in common cowslip (Primula veris L.) compared to common foodplants and orange juices

86%

Meos A., Zaharova I., Kask M., Raal A.

Acta Biologica Cracoviensia s. Botanica

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2017

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vol. 59

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issue 1

5

Flavonoid and Organic Acid Content in Rose Hips (Rosa L., Sect. Caninae Dc. Em. Christ.)

72%

Adamczak A., Buchwald W., Zieliński J., Mielcarek S.

Acta Biologica Cracoviensia s. Botanica

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2012

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vol. 54

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issue 1

6

The dynamics of vitamin C content in fresh and processed cucumber (Cucumis sativus L.) / Dynamika zmian zawartości witaminy C w ogórku świeżym (Cucumis sativus L.) i jego przetworach

72%

Grzelakowska A., Cieślewicz J., Łudzińska M.

Chemistry-Didactics-Ecology-Metrology

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2013

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vol. 18

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issue 1-2

97-102

EN

The objective of the proposed experiment was to determine changes in the content of vitamin C in the vegetable material (fresh and processed) during a certain period of time, and to determine the optimal expiry date of a product (in terms of the vitamin C content), as well as to introduce students to common factors adversely affecting the content of vitamin C in food products (with a special emphasis on oxidizing enzymes). The research revealed that regardless of the type of cucumbers (fresh, pickled in brine or in vinegar), the content of vitamin C is rapidly dropping after the destruction of the cellular structure (grating, slicing etc.). In the case of fresh cucumbers, it is a process determined by two factors: release and activation of ascorbinase from the destroyed cellular structure and availability of oxygen. Low pH values in the remaining cases reduce the effect of ascorbinase, and a decrease in the vitamin C content is related to the process of oxidation with atmospheric oxygen.

PL

Celem proponowanego ćwiczenia było podjęcie próby określenia zmian zawartości witaminy C w surowcu roślinnym oraz jego przetworach w czasie i określenia optymalnego czasu spożycia produktu (ze względu na zawartość witaminy C) oraz zapoznanie studentów z powszechnie występującymi czynnikami niekorzystnie wpływającymi na zawartość witaminy C w produktach żywnościowych (ze szczególnym uwzględnieniem enzymów z grupy oksydaz). Przeprowadazone badania wykazały, że niezależnie od rodzaju ogórków (świeże, kiszone, konserwowe) po zniszczeniu stuktury komórkowej (tarcie, krojenie itd.) zawartość witaminy C gwałtownie spada. W przypadku ogórków świeżych jest to proces determinowany przez dwa czynniki: uwolnienie i aktywacja askorbinazy ze zniszczonych struktur komórkowych oraz dostęp tlenu. Niskie wartości pH w pozostałych przypadkach ograniczają działanie askorbinazy, a spadek zawartości witaminy C jest związany z procesem utleniania tlenem atmosferycznym.

7

Free radical scavengers can modulate the DNA-damaging action of alloxan.

72%

Blasiak J., Sikora A., Czechowska A., Drzewoski J.

Acta Biochimica Polonica

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2003

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vol. 50

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issue 1

205-210

EN

Alloxan can generate diabetes in experimental animals and its action can be associated with the production of free radicals. It is therefore important to check how different substances often referred to as free radical scavengers may interact with alloxan, especially that some of these substance may show both pro- and antioxidant activities. Using the alkaline comet assay we showed that alloxan at concentrations 0.01-50 μM induced DNA damage in normal human lymphocytes in a dose-dependent manner. Treated cells were able to recover within a 120-min incubation. Vitamins C and E at 10 and 50 μM diminished the extent of DNA damage induced by 50 μM alloxan. Pre-treatment of the lymphocytes with a nitrone spin trap, α-(4-pyridil-1-oxide)- N-t-butylnitrone (POBN) or ebselen (2-phenyl-1,2-benzisoselenazol-3(2H)-one), which mimics glutathione peroxides, reduced the alloxan-evoked DNA damage. The cells exposed to alloxan and treated with formamidopyrimidine-DNA glycosylase (Fpg) and 3-methyladenine-DNA glycosylase II (AlkA), enzymes recognizing oxidized and alkylated bases, respectively, displayed greater extent of DNA damage than those not treated with these enzymes. The results confirmed that free radicals are involved in the formation of DNA lesions induced by alloxan. The results also suggest that alloxan can generate oxidized DNA bases with a preference for purines and contribute to their alkylation.

8

Rola witamin antyoksydacyjnych w złośliwych nowotworach ginekologicznych

58%

Markowska A., Jaszczyńska-Nowinka K., Kaysiewicz J., Makówka A., Markowska J.

Current Gynecologic Oncology

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2016

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vol. 14

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issue 1

39-52

EN

Vitamins D, C, E and A, which belong to antioxidants, exhibit anticancer activity. The mechanism of vitamin D antitumor activity involves the inhibition of cell proliferation, stimulation of apoptosis, inhibition of angiogenesis and an increased activity of metalloproteinases in the extracellular matrix. Vitamin D prevents the development and progression of breast cancer; its lower levels in the serum of premenopausal women are linked to the development of triple negative cancer (E-, PR-, HER2-). Cohort studies on the effects of VDR (vitamin D receptor) polymorphisms and studies related to vitamin D supplementation in postmenopausal women in the context of reduced risk of breast cancer are controversial. Vitamin D exerts a protective effect against ovarian and endometrial cancer. Vitamin C protects cells against the formation of mutagenic nitro compounds, enhances the immune system by promoting the activity of NK, T and B cells. Vitamin C supplementation improves treatment outcomes in disseminated breast cancer; the vitamin acts synergistically with cisplatin, it increases paclitaxel and doxorubicin cytotoxicity and abolishes toxic effects of tamoxifen. Vitamin C combined with chemotherapy in ovarian cancer prolongs patient’s survival. It increases sensitivity to cisplatin. Vitamin E exerts anticancer effects via multiple pathways. Its increased administration reduces the risk of breast cancer and ovarian cancer. The reduction in the incidence of endometrial cancer remains controversial. Vitamin A also exerts antioxidant effects. The compound reduces the incidence of DNA damage in cells exposed to hydrogen peroxide and protects cell organelles (including mitochondria) against the negative impact of lipid peroxidation. It reduces the risk of multiple tumors, including breast and cervical cancer.

PL

Witamina D oraz witaminy C, E i A, należące do antyoksydantów, wykazują aktywność przeciwnowotworową. Mechanizm działania witaminy D obejmuje hamowanie proliferacji komórkowej, stymulację apoptozy, hamowanie angiogenezy i zwiększanie aktywności metaloproteinaz macierzy pozakomórkowej. Witamina D zapobiega rozwojowi raka piersi i progresji choroby; niższe jej stężenia w surowicy kobiet przed menopauzą wiążą się z rozwojem raków potrójnie negatywnych (E-, PR-, HER2-). Badania kohortowe dotyczące wpływu polimorfizmów genu VRD (vitamin D receptor) oraz badania nad suplementacją witaminy D po menopauzie w kontekście redukcji rozwoju raka piersi są kontrowersyjne. Witamina D ma protekcyjny wpływ w przypadku raka jajnika i endometrium. Witamina C chroni komórki przed mutagennym tworzeniem nitrozwiązków, wzmacnia funkcjonowanie układu immunologicznego przez wzrost aktywności komórek NK oraz limfocytów T i B. Stosowanie witaminy C poprawia wyniki leczenia rozsianego raka piersi; działa ona synergistycznie z cisplatyną, zwiększa cytotoksyczność paklitakselu i doksorubicyny, znosi toksyczny wpływ tamoksyfenu. Witamina C w skojarzeniu z chemioterapią przyczynia się do dłuższego przeżycia pacjentek z rakiem jajnika i poprawia wrażliwość na stosowaną cisplatynę. Witamina E działa przeciwnowotworowo przez wiele ścieżek. Jej zwiększona podaż wiąże się ze spadkiem ryzyka wystąpienia raka piersi i raka jajnika. Obniżenie ryzyka zachorowania na raka endometrium jest kontrowersyjne. Witamina A także ma działanie antyoksydacyjne. Obniża częstość uszkodzeń DNA indukowanych nadtlenkiem wodoru i chroni organella komórkowe (w tym mitochondria) przed negatywnymi skutkami peroksydacji lipidów. Zmniejsza ryzyko rozwoju wielu nowotworów, w tym raka piersi i szyjki macicy.

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Effects of organic compounds on the macroalgae culture ofAegagropila linnaei

Protective action of vitamin C against DNA damage induced by selenium-cisplatin conjugate.

Size-dependent growth kinetics of vitamin C crystals in water solutions of L(+)-ascorbic acid with the addition of methanol and ethanol

Content of ascorbic acid in common cowslip (Primula veris L.) compared to common foodplants and orange juices

Flavonoid and Organic Acid Content in Rose Hips (Rosa L., Sect. Caninae Dc. Em. Christ.)

The dynamics of vitamin C content in fresh and processed cucumber (Cucumis sativus L.) / Dynamika zmian zawartości witaminy C w ogórku świeżym (Cucumis sativus L.) i jego przetworach

Free radical scavengers can modulate the DNA-damaging action of alloxan.

Rola witamin antyoksydacyjnych w złośliwych nowotworach ginekologicznych