2018, Vol. 82 No. 1
Stały URI dla kolekcjihttp://hdl.handle.net/11652/5426
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Pozycja Application and properties of selected flavanones(Wydawnictwo Politechniki Łódzkiej, 2018) Błazińska, Paulina; Sykuła, AnnaFlavanones, secondary plant metabolites, are one of the main group of flavanoids. They are widely spread in nature in many plants. The large diversity of structural structure of flavanones and controlled methods of modifying their molecules have a huge impact on biological activity. The present review will summarize the current knowledge about occurrence, obtaining by chemical synthesis, application and bioactivity of flavanones. Also, they are received from specific chemical synthesis. Flavanones have a great biological activity. Derivatives of flavanone have many different properties such as anti-inflammatory, anticancer, antioxidant, antimicrobial or hepatoprotective activities. These natural polyphenolic compounds are used in cosmetology, pharmacy and medicine. The demand and usage on them increases.Pozycja Analysis of the selected antioxidant compounds n ice cream supplemented with Spirulina (Arthrospira platensis) extract(Wydawnictwo Politechniki Łódzkiej, 2018) Szmejda, Klaudia; Duliński, Robert; Byczyński, Łukasz; Karbowski, Adrian; Florczyk, Tomasz; Żyła, KrzysztofThe research is aimed at evidencing that ice-cream formulations incorporating algae can have health-benefiting effects on human body. The main task of the project is to design ice-cream product line that distinguish itself from regular ice-cream by increased anti-oxidant activity resulted from inclusion of the algae extract. The currently known research evidences that ice-cream can be effective as carriers of health-promoting probiotic bacteria, which in turn encourages also application of other microorganisms in particular algae of specific strains (e.g. Spirulina platensis) as a supplement to ice-cream. In submitted research, the level of polyphenols and antioxidant activity expressed as degree of inhibiting generation of cationo-free radical from DPPH•+ solution were analyzed. Preliminary results based on antioxidative activity tests measured with potential to quench free radicals have shown that ice-cream formulations enriched with algae extract exhibit significantly higher potential achieving inhibition level of 39.7% in the mint ice cream samples as compared to 32.8% inhibition for the control sample without algae. Furthermore, each of the examined samples (dairy, pistachio, mint) ice creams versions supplemented with Spirulina were characterized by enhanced antioxidant activities expressed as potential to quench free radicals and the carotenoids content.Pozycja The DFT study on the electronic structure of boronic acid derivatives and its esters with fructose(Wydawnictwo Politechniki Łódzkiej, 2018) Kur, Katarzyna; Kowalska-Baron, Agnieszka; Miller, EwaTheoretical investigations are carried out to examine the geometrical structure and parameters of electron transitions to the lowest excited states of two boronic acid derivatives: 3-aminophenylboronic acid and 3-(acetamidomethyl)phenyl boronic acid and its cycling esters with fructose, using the DFT based 6-31 G(d,p) method. The most stable ester isomer of each acid has been selected. Predicted excitation wavelength are shorter (less than 0.5 eV) than experimental ones, what is in a good agreement considering limitations of the DFT method. In case of almost every calculated molecule the analysis of electronic transitions shows that transition S0→S1 involves electron transfer mainly from the HOMO to LUMO orbital.Pozycja Optical properties of (3-(acetamidomethyl)phenyl) boronic acid and its interactions with selected sugars(Wydawnictwo Politechniki Łódzkiej, 2018) Kur, Katarzyna; Przybyt, Małgorzata; Miller, Ewa(3-(Acetamidomethyl)phenyl)boronic acid (3AAPBA)has at pH 7 absorbance maximum at 270 nm with molar absorbance coefficient 516 M-1cm-1. 3AAPBA exhibits weak fluorescence with maximum at 297 nm and quantum yield 0.062 ± 0.001. Fluorescence decay is monoexponential and the lifetime is 2.05 ± 0.01 ns. Interactions of 3AAPBA with selected sugars were studied by absorbance, steady-state and time-resolved fluorescence measurements. At pH 7 fluorescence of 3AAPBA is quenched only by fructose (with quenching constant 67.9 M-1) and to some extend by galactose. Addition of these two monosaccharides causes also changes of absorbance spectra of 3AAPBA. Acid-base dissociation of free 3AAPBA and its esters with sugars was studied by absorbance and steady-state fluorescence measurements in pH range from 4.5 to 11.00. Esterification of phenylboronic acid derivatives by sugars leads to increased acidity of them. In case of 3AAPBA the obtained values of pK indicate that affinity of studied sugars towards it can be ordered as follows: fructose > galactose > glucose > maltose > lactose > sucrose. At pHs higher than pK the fluorescence decays turn to biexponential with additional shorter component in lifetime which we propose to attribute to anionic form of 3AAPBA or its esters.Pozycja Antioxidant Potential and Phytochemical Content of Selected Fruits and Vegetables Consumed in Cyprus(Wydawnictwo Politechniki Łódzkiej, 2018) Georgiadou, Egli C; Goulas, Vlasios; Majak, Iwona; Ioannou, Antigoni; Leszczyńska, Joanna; Fotopoulos, VasileiosConsuming a diet high in fruits and vegetables can lower the risk of developing numerous chronic diseases, including cancer and cardiovascular disease, due to the presence of multiple antioxidants. Horticultural produce consumed in Cyprus include a large variety of fruits and vegetables, most of which are common components of a Mediterranean-style diet due to the island’s localization. The aim of the present study was to evaluate the antioxidant composition and activity of the edible portion of ten fruits and ten vegetables commonly consumed in Cyprus. Total phenolics, anthocyanins, ascorbic acid and carotenoids contents were determined, while the in vitro antioxidant activity was evaluated by three assays. Antioxidant activity showed great variation, with the highest values found in green olives, capers and red chili peppers and in correlation with total phenolic content. Ascorbic acid was detected in large quantities in parsley, coriander, red guavas and red chili peppers, while red chili peppers, capers and coriander had high levels of carotenoids. Furthermore, sweet cherries, red grapes, and red apples contained significant amounts of anthocyanins. Statistical analysis revealed that phenolic compounds are the most potent antioxidants in fruit and vegetables, while total anthocyanins had a weak contribution to their antioxidant activity. The present study could be a guide for Cypriot as well as Mediterranean diet health-conscious consumers to select specific fruits and vegetables as dietary components. To the best of our knowledge, this is the first study thoroughly describing the antioxidant composition and activity of a wide array of important Cypriot horticultural products.