Wyniki wyszukiwania - Biblioteka Nauki

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Assessment of poultry eggs freshness using FTIR spectroscopy combined with HCA and PCA methods

100%

Michalczyk E. , Kurczab R.

Science, Technology and Innovation

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2018

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tom Vol. 2, no. 1

7--12

EN

The main aim of this study was to investigate the use of Attenuated Total Reflection Fourier Transform Infrared Spectroscopy (ATR FTIR) and selected chemometric methods to classify eggs in terms of the laying hen farming method, as well as to identify changes in the individual egg compositions during storage. In total, 50 eggs were used for the study; 10 eggs per classes: 0, 1, 2, 3 and rural. Eggs were stored by 29 days period, which was divided on the 10 measuring days in which one egg from each class was tested by recording two FTIR spectra for the shell, albumen and egg yolk. The chemometric analysis, including Hierarchical Cluster Analysis (HCA) and the Principal Component Analysis (PCA), was performed based on the recorded FTIR spectra. Changes in chemical composition during the experiment in individual egg elements were analyzed. Furthermore, by analyzing the graphs (HCA and PCA) obtained by the chemometric analysis, it was noted that the largest changes in the chemical composition of eggs occurred in the shell and yolk, while in the albumen it was less insignificant. The chemometric analysis of the recorded spectra also showed that combination of chemometric methods and FTIR spectroscopy can potentially be used to develop a non-destructive method for classifying eggs in terms of the hen culture method and to monitor of their freshness.

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Oddziaływanie dihydroksyacetonu (DHA) zawartego w samoopalaczach z ludzką skórą – badania spektroskopowe i teoretyczne

80%

Pietruś W. , Kurczab R. , Latowski D.

Tarnowskie Colloquia Naukowe. Nauki Techniczne i Ścisłe

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2017

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tom T. 4, nr 3

79--90

PL

Celem pracy było zbadanie wybranych właściwości ośmiu samoopalaczy różniących się konsystencją i zawartością dihydroksyacetonu (DHA). Badane bronzery podzielono na trzy grupy: płynne produkty samoopalające zawierające około 15% DHA, półpłynne samoopalacze (spryskiwacze lub pianki) oraz bronzery w postaci kremu. Produkty z tych dwóch ostatnich grup zawierały około 5% DHA. Badanie miało na celu sprawdzenie, czy samoopalacze są w stanie absorbować promieniowanie UV. Celem zastosowania spektroskopii w podczerwieni było zbadanie wpływu samoopalaczy na poziom nawilżenia skóry. W trakcie pracy wykonano obliczenia kwantowo-mechaniczne. Obliczenia dotyczyły komputerowego modelowania przepuszczalności DHA przez warstwę beta-keratyny skóry. Obliczono również energię wiązania wodorowego pomiędzy łańcuchami beta-keratyny oraz powierzchnię wykrystalizowanej formy beta-keratyny. Wyniki badań wykazały, że DHA bardzo silnie absorbował promieniowanie UV-C, natomiast w mniejszym stopniu promieniowanie UV-B. Najmniejsza absorbancja została zarejestrowana w zakresie promieniowania UV-A. Płynne i częściowo półpłynne samoopalacze obniżyły poziom nawilżenia skóry, natomiast produkty w postaci kremu zawierały substancje nawilżające, które neutralizowały negatywny wpływ DHA na nawilżenie skóry. W badaniach in silico wykazano, że DHA nie przenika przez warstwę beta-keratyny skóry. Potencjalnymi przyczynami mogą być duże ilości energii wiązań wodorowych i naładowana powierzchnia beta-keratyny.

EN

The purpose of this study was to investigate selected properties of eight bronzers differing in consistency and dihydroxyacetone (DHA) content. The investigated bronzers were divided into three groups including: liquid sunless tanning products containing DHA level of about 15%, half-liquid self-tanners (spray or foam), and bronzers in the form of a cream. The products from the two latter groups contained about 5% DHA. This study inspected if self-tanners have the ability to absorb UV radiation. The aim of using infrared spectroscopy was to investigate the influence of self-tanners on skin moisture level. During the study, quantum-mechanical calculations were done. The calculations were related to computer-based modeling of DHA permeability through the beta-keratin layer of the skin. The calculations were also done to estimate hydrogen bond energy between chains of the beta-keratin as well as the surface of the crystallized beta-keratin surface. The results indicated that DHA absorbed UV-C radiation very strong, whereas UV-B radiation was absorbed to a lower degree. The least absorbancy was discovered in the UV-A range. Liquid and, partly, half-liquid self-tanners reduced skin moisture; however, products in the form of cream contained moisturizing substances that neutralize the negative effect of DHA on skin hydration. In silico studies indicated that DHA does not permeate through the beta-keratin layer of the skin. Potential reasons for this may be the large energy of hydrogen bonds and charged beta-keratin surface

3

Pochodne pirazolowe : wyzwanie współczesnej chemii akademickiej i przemysłowej

61%

Popielarska H. , Myka A. , Drabińska B. , Gruszeczka A. , Kruk J. , Kurczab R. , Kujawski J.

Przemysł Chemiczny

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2013

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tom T. 92, nr 6

905--914

4

Low-basicity agonists of serotonin 5-HT7 receptors

41%

Hogendorf A. S. , Hogendorf A. , Kurczab R. , Satala G. , Lenda T. , Walczak M. , Latacz G. , Handzlik J. , Kiec-Kononowicz K. , Wieronska J. , Wozniak M. , Cieslik P. , Bugno R. , Staron J. , Bojarski A. J.

Acta Neurobiologiae Experimentalis

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2017

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tom 77

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nr Suppl.1

EN

The 5-HT7R is involved in many physiological processes, i.e. the regulation of body temperature, circadian rhythm, learning and memory, as well as pathophysiological processes such as mood disorders, anxiety, schizophrenia and pain. None of the known 5-HT7R agonists qualify as perfect radioligand candidates, mainly due to their poor selectivity, metabolic stability or non-optimal ADME properties. Development of new ligands of 5-HT7R of the unique structure and properties. The compounds were concisely synthesized using van Leusen multi-component protocol and receptor affinity (5‑HT7, 1A, 2A, 6, and D2) was tested in radioligand binding assays. The intrinsic clearance was determined using human liver microsomes, whereas cytotoxicity was measured on HEK-293 and HepG2 cells. The pharmacokinetics of a lead compound was tested on CD-1 mice at 5 mg/kg dose (i.p.). The compound ability to reverse MK-801 induced impairment in novel object recognition test was conducted on Albino Swiss mice. Results: We have developed a series of 5-HT7R ligands, which are one of the very few examples of low-basicity aminergic receptor agonists. Lead compounds exhibited high affinity for the 5‑HT7R as well as high efficacy as agonists, excellent selectivity over related CNS targets, high metabolic stability and low toxicity. Docking to 5-HT7R homology models indicated a plausible binding mode which explain the unusually high selectivity. A rapid absorption to the blood, high blood-brain barrier permeation and a very high peak concentration in the brain were found for the lead compound. It was also found active in the NOR test. Because the compounds fulfill all the requirements needed for a PET radioligand a synthetic method which enables the incorporation of 11C isotope was developed. The obtained group of selective, low-basicity 5-HT7R receptor agonists has a great potential to be developed as pharmacological tools, radioligands or drug candidates. FINANCIAL SUPPORT: The study was partially supported by the Polish-Norwegian Research Programme operated by the National Centre for Research and Development under the Norwegian Financial Mechanism 2009–2014 in the frame of the Project PLATFORMex (Pol-Nor/198887/73/2013), www.platformex.eu.