This thesis is focused to the analysis of selected varieties of honeysuckle kamtschatica (Lonicera caerula var kamtschatica) and their comparison in terms of the content of biologically active substances. There were analysed only varieties grown in 2014. Theoretical part elaborates and characterized various parameters of biologically active compounds such as phenolic, anthocyanins and ascorbic acid and possibilities of their determination. Further it briefly surveys Kamchatka honeysuckle, its taxonomic and morphological properties and its nutritional properties. The experimental part of the work was focused on the description of the methods used for the analysis of biologically active substances and their analysis. Polyphenolic compounds and anthocyanin’s were determined spectrophotometrically and vitamin C was determined by high-performance liquid chromatography. The results and varieties were compared with each other. Overall, we can say that the variety with the highest content of all three analysed biologically active substances is a variety Valchová, which had the second highest content of polyphenolic compounds (546.3 mg · 100 g-1 fruits), the third highest contend of ascorbic acid (35.1 mg · 100 g-1 fruits) and the sixth highest content of anthocyanin (170.8 mg · 100 g-1 fruits)

The present thesis work is dedicated to the implementation of novel electrochemical methods for the assay of drug compounds such as paracetamol and ascorbic acid and biologically relevant biothiols such as cysteine and glutathione. Particular attention has been paid to the development and application of amperometric detectors allowing for a readily surface renewing and for highly selective and sensitive assays.<p>Coupling of a screen printed electrochemical detector with a monolithic chromatographic column was performed for high-throughput analysis along with selectivity, sensitivity and good precision. The modification of a glassy carbon electrode with a perm-selective membrane was investigated in order to provide an electrochemical sensor for on-site analysis. Acetaminophen was investigated as a model drug compound because of its extensive use in drug “pain killer” medication.<p>Along with the aims of this thesis, a silver polycrystalline electrode was investigated as a sensitive and class selective electrode for the assay of small thiol-based molecules. The silver electrode was implemented for the first time as an amperometric detector coupled to liquid chromatography for the assay of thiols. Application to the study of thiol species present in white wines was realized in order to illustrate the potential of the silver working electrode as amperometric detector. / Doctorat en Sciences biomédicales et pharmaceutiques / info:eu-repo/semantics/nonPublished

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No description available.

As frutas deteriorarem-se em poucos dias, tendo sua comercialização in natura dificultada a grandes distâncias. Além disso, estima-se que as perdas pós-colheita variem de 15 a 50% do total. Desta forma, a produção de polpas de frutas congeladas se tornou um meio favorável para o seu aproveitamento integral na época da safra, evitando os problemas ligados à sazonalidade. Os flavonóides e o ácido ascórbico presente em frutas apresentam atividade antioxidante, associada à menor incidência de crônico-degenerativas. Os objetivos deste trabalho foram avaliar o efeito do armazenamento em condições comerciais (-18 ºC) de polpas de frutas (acerola, açaí, amora e morango) e o efeito do processamento artesanal para sua obtenção sobre os teores de flavonóides, vitamina C e atividade antioxidante in vitro. A composição dos flavonóides e os teores de vitamina C foram determinados por CLAE, o teor de fenólicos totais através do método Folin-Ciocalteu, e a atividade antioxidante pelo método de co-oxidação do &#946;-caroteno/ácido linoléico e através do seqüestro de radicais livres do DPPH. Os resultados mostraram que o efeito do processamento para obtenção das polpas de frutas congeladas sobre os teores de compostos fenólicos e vitamina C varia de acordo com o fruto. No caso do morango e da amora, as polpas apresentaram teores similares aos seus respectivos frutos. Já para acerola, a separação do epicarpo e das sementes durante o processo de despolpamento ocasionou um aumento do teor de vitamina C e diminuição do teor de flavonóides na polpa. O armazenamento de polpas congeladas de morango, amora, açaí e acerola em condições comerciais (-18 ºC), por até um ano, não afeta os teores de flavonóides, vitamina C, fenólicos totais e atividade antioxidante. / The fruits become deteriorated in few days, therefore their commercialization is difficult for long distances. Thus, production of frozen fruits pulps become a favorable method for utilization of the integral fruit. The fruits containing flavonoids and ascorbic acid that are bioactive compounds that present antioxidant activity due to their ability of reducing the formation of free radicals, besides the possible effects in reducing the incidence of chronic degenerative diseases. The objective of this work was to verify the effect of the storage at commercial conditions (-18°C) of frozen fruits pulps (acerola, açaí, blackberry and strawberry) and the effect of the artisan processing on the flavonoids, vitamin C contents and antioxidant activity. Flavonoids and vitamin C contents were determined by HPLC, total phenolics contents through the Folin-Ciocalteu method, and the antioxidant activity was evaluated by the linoleic acid/&#946;-carotene system and by measuring DPPH free-radical scavenging capacity. The results showed that the effect of processing for obtainment of frozen fruits pulps on total phenolics and vitamin C changed according to the fruit analysed. The fruits pulps of strawberry and blackberry showed similar contents to their respective fruits. In acerola, epicarp and seeds separation during the processing increased the vitamin C contents and decreased the flavonoids contents in pulp. In conclusion, the storage of frozen fruits pulps of acerola, açaí, strawberry and blackberry at commercial conditions (-18ºC) during a year, did not affect the flavonoids, vitamin C, phenolics total contents and antioxidant activity.

A potencialidade do eletrodo de cobre em meio alcalino foi demonstrada para o determinação de etanol a +0,6 V vs Ag/AgCl. A participação de espécies solúveis de Cu(III) no processo eletrocatalítico envolvendo a oxidação do etanol foi demonstrada por experimentos utilizando eletrodo disco-anel. A influência do potencial de pré-tratamento no sinal anódico foi investigada e correlacionada com a morfologia dos filmes formados na superfície do eletrodo por EDS (Energy Dispersive X-Ray Spectroscopy), indicando que as espécies de Cu(III) são originadas a partir da oxidação da camada de CuO. As medidas de etanol foram realizadas por amperometria em 0,6 V (vs Ag/AgCl). A repetibilidade das medidas utilizando padrão aquoso de etanol 0,05 % (v/v) foi de 3 % (v/v) e os limites de detecção e quantificação foram de 0,005 % (v/v) e 0,01 % (v/v), respectivamente. Nas condições experimentais otimizadas, o sensor amperométrico foi utilizado para o monitoramento da concentração de etanol no ar exalado (BrAC), que foi convenientemente coletado em um balão de borracha (V = 3 L) e introduzido em uma solução de NaOH 1 mol L-1 (V = 10 mL). O sensor apresentou uma faixa linear para concentrações de etanol em ar exalado na faixa de 0,26 – 130 mg L-1, operando de acordo com os parâmetros analíticos especificados na Legislação Brasileira para a quantificação de etanol no ar exalado em condutores de veículos automotores. A constante de eliminação de etanol do corpo humano também foi investigada e os resultados concordaram com os valores da literatura. Empregando-se eletrodos de Cu e Au foram também desenvolvidas outras metodologias para a quantificação de dipirona, glicose e ácido ascórbico e sistemas em fluxo. Estudos sobre o desenvolvimento e propriedades de um sistema gerador-coletor foram realizados e o dispositivo foi utilizado em titulações de substâncias redutoras com iodo gerado eletroquimicamente. / A copper disc working electrode in alkaline solutions was demonstrated to act as a suitable amperometric sensor for ethanol determination at +0.6 V vs Ag/AgCl. The participation of free-soluble Cu(III) species in the electrocatalytic process involving the anodic oxidation of ethanol has been demonstrated by rotating ring-disc electrode voltammetry. The influence of the pretreatment potential on the anodic signal was investigated and a correlation with the morphology of the electrode surface characterized by Energy Dispersive X-Ray Spectroscopy (EDS) indicated that the Cu(III) species is originated from the oxidation of a CuO layer. Ethanol measurements were performed in the amperometric mode at 0.6 V (vs Ag/AgCl). The repeatability of the measurements for a 0.05 % aqueous ethanol solution was estimated as 3 %, and the detection and quantification limits were determined as 0.005 % and 0.01 %, respectively. At the optimum experimental conditions, the amperometric sensor was used to monitor the concentration of ethanol in breath (BrAC), which was conveniently collected in a rubber air balloon (volume = 3 L) and introduced in a 1 mol L-1 NaOH working solution (volume = 10 mL). The sensor can measure a person\'s breath ethanol over the concentration range 0.26 - 130 mg L-1 by operating it according to an established protocol, of which the analytical parameters are specified by the Brazilian Legislation for BrAC measurements in drivers. The rate of ethanol degradation in the body was followed, and the results agree with predictions in the literature. Methodologies for the determination of dipyrone, glucose and ascorbic acid were also developed by using Cu and Au electrodes. Features of a dual-band electrochemical cell were investigated towards the development of a generator-collector system, which was employed in titrations with electrogenerated iodine.

<p>&nbsp;&nbsp; Cilj ove doktorske disertacije predstavljao je ispitivanje fitohemijskog sastava i biolo&scaron;ke aktivnosti vodenih i metanolnih ekstrakata svežih i suvih plodova, kao&nbsp; i pekmeza&nbsp; pripremljenog&nbsp; po tradicionalnoj recepturi od plodova&nbsp; četiri (od kojih se jedna javlja u dve forme)&nbsp; samonike&nbsp; vrsta&nbsp; roda&nbsp; <em>Sorbus</em>&nbsp; L.:&nbsp; S.<em> aucuparia</em>, S.<em> domestica</em>, S. <em>torminalis</em>&nbsp; f.&nbsp; t<em>orminalis</em>, S. <em>torminalis</em>&nbsp; f. <em>semitorminalis</em>&nbsp; i&nbsp; S. intermedia Ispitivanje fitohemijskog sastava obuhvatalo je LC-MS/MS analizu&nbsp; 44 odabrana fenolna jedinjenja&nbsp; i&nbsp; hinske kiseline (organska&nbsp; kiselina). Takođe, spektrofotometrijski je&nbsp; određen&nbsp; sadržaj&nbsp; ukupnih fenolnih i flavonoidnih jedinjenja, kao i&nbsp; sadržaj askorbinske kiseline. Evaluacija biolo&scaron;ke aktivnosti obuhvatala je&nbsp; <em>in vitro&nbsp; </em>ispitivanja antioksidantne aktivnosti, kao i ispitivanje uticaja ekstrakata odabranih vrsta&nbsp; roda&nbsp;<em> Sorbus</em>&nbsp; na aktivnost enzima acetilholinesteraze, antimikrobni, kao i antiproliferativni potencijal.</p><p>&nbsp;&nbsp; Sumiranjem dobijenih rezultata može se zaključiti da sveži i suvi plodovi ispitivanih vrsta&nbsp; <em>Sorbus</em>,&nbsp; kao i&nbsp; pekmezi&nbsp; predstavljaju&nbsp; umeren izvor&nbsp; fenolnih jedinjenja.&nbsp; Kao najzastupljenije fenolne kiseline izdvojile su se protokatehinska i&nbsp; ferulna, a među flavonoidima amentoflavon i kvercetin-3<em>-O-</em>glukozid.&nbsp; Pored toga, hinska kiselina je zabeležena u značajnoj količini u svim analiziranim ekstraktima.</p><p>&nbsp;&nbsp;&nbsp; Ekstrakti ispitivanih vrsta pokazali su&nbsp; umeren&nbsp; antioksidantni potencijal koji se ogleda u njihovoj sposobnosti neutralizacije nekoliko radikalskih vrsta, redukcionom potencijalu i sposobnosti inhibicije lipidne peroksidacije.&nbsp; Ispitivanjem uticaja ekstrakata odabranih vrsta&nbsp;<em> Sorbus</em>&nbsp; naaktivnost&nbsp; enzima&nbsp; acetilholinesteraze&nbsp; dokazana&nbsp; je&nbsp; jedino&nbsp; umerena aktivnost&nbsp; ekstrakata vrste&nbsp; <em>S. aucuparia</em>.&nbsp; Takođe, ispitivani ekstrakti&nbsp; vrsta roda&nbsp; <em>Sorbus</em>&nbsp; ispoljili su umerenu&nbsp; antimikrobnu&nbsp; aktivnost u pogledu inhibicije&nbsp; rasta Gram pozitivne bakterije,&nbsp; <em>Staphylococcus aureus</em>, i Gram negativne bakterije,&nbsp;<em> Escherichia coli</em>.&nbsp; Vodeni i metanolni ekstrakti svežih i suvih plodova vrste&nbsp; <em>S. aucuparia</em>&nbsp; pokazali su umeren i inhibitorni potencijal prema rastu tumorskih (HeLa, MCF7, HT-29), ali i netumorskih ćelijskih linija (MRC-5).&nbsp; Rezultati dobijeni u ovoj doktorskoj distertaciji&nbsp; ukazuju na značajan&nbsp; biopotencijal plodova i pekmeza&nbsp; ispitivanih vrsta&nbsp;<em> Sorbus</em>&nbsp; i ukazuju na njihovu primenu u prehrambenoj industriji u vidu funkcionalne hrane.</p> / <p>The aim of presented&nbsp; PhD&nbsp; thesis was investigation of phytochemical composition and biological activity of water and methanol extracts of fresh and air-dried&nbsp; fruits, as&nbsp;&nbsp; well&nbsp; as&nbsp; jam,&nbsp; made according to traditional recipe,&nbsp; of fruits&nbsp; of four&nbsp; (one of them occurs in two forms)&nbsp; wild growing&nbsp; <em>Sorbus</em>&nbsp; L. species:&nbsp; <em>S. aucuparia, S. domestica, S. torminalis&nbsp; f. torminalis, S. torminalis f. semitorminalis</em> and <em>S. intermedia</em>. Examination of phytochemical composition included LC-MS/MS analysis of 44 selected phenolic compounds&nbsp; and&nbsp; quinic acid (organic acid).&nbsp; Also, total phenolic and flavonoid contents, as well as&nbsp; ascorbic acid&nbsp; content,&nbsp; were determined spectrophotometrically. Biological activity evaluation of extracts of<em>&nbsp; Sorbus</em>&nbsp; species included&nbsp;<em> in vitro&nbsp;</em> investigation of antioxidant, anti-acetylcholinesterase, antimicrobial&nbsp; and cytotoxic activity.</p><p>&nbsp;&nbsp; According to obtained results, fresh and air-dried&nbsp; fruits, as well as jam&nbsp; present&nbsp; moderate&nbsp; source of phenolic compounds. Amongs examined phenolic acids protocatechuic&nbsp; and ferulic acids were the most abundant, and amongs investigated flavonoids amentoflavone and quercetin-3-<em>O</em>-glucoside wete present in noticeable amount.&nbsp; Furthermore, high concentration of quinic acid was present in all examined extracts.</p><p>&nbsp;&nbsp; Extracts of all examined species showed&nbsp; moderate&nbsp;&nbsp; antioxidant activity in terms of radical scavenging ability, reduction potential and inhibition of lipid peroxidation.&nbsp; Also, investigation of&nbsp; anti-acetylcholinesterase activity revealed moderate activity only of extracts of <em>S. aucuparia</em>. Furthermore, examinated extracts of<em> Sorbus</em> species showedmoderate antimicrobial activity against Gram&ndash;positive bacteria, <em>Staphylococcus aureus</em>, and Gram-negative bacteria,&nbsp;<em> Escherichia coli</em>.&nbsp; In addition, water&nbsp; and methanol&nbsp; extracts of fresh and air-dried&nbsp; fruits of&nbsp;<em> S.aucuparia</em>&nbsp; showed&nbsp; inhibitory activity toward&nbsp; tumor (HeLa, MCF7, HT-29), and also non-tumor (MRC-5) cell lines. Presented results indicate significant&nbsp; biopotential of examined&nbsp; fruits of&nbsp; <em>Sorbus&nbsp;</em> species&nbsp; and&nbsp; support their use in food industry as functional food.</p>

As frutas deteriorarem-se em poucos dias, tendo sua comercialização in natura dificultada a grandes distâncias. Além disso, estima-se que as perdas pós-colheita variem de 15 a 50% do total. Desta forma, a produção de polpas de frutas congeladas se tornou um meio favorável para o seu aproveitamento integral na época da safra, evitando os problemas ligados à sazonalidade. Os flavonóides e o ácido ascórbico presente em frutas apresentam atividade antioxidante, associada à menor incidência de crônico-degenerativas. Os objetivos deste trabalho foram avaliar o efeito do armazenamento em condições comerciais (-18 ºC) de polpas de frutas (acerola, açaí, amora e morango) e o efeito do processamento artesanal para sua obtenção sobre os teores de flavonóides, vitamina C e atividade antioxidante in vitro. A composição dos flavonóides e os teores de vitamina C foram determinados por CLAE, o teor de fenólicos totais através do método Folin-Ciocalteu, e a atividade antioxidante pelo método de co-oxidação do &#946;-caroteno/ácido linoléico e através do seqüestro de radicais livres do DPPH. Os resultados mostraram que o efeito do processamento para obtenção das polpas de frutas congeladas sobre os teores de compostos fenólicos e vitamina C varia de acordo com o fruto. No caso do morango e da amora, as polpas apresentaram teores similares aos seus respectivos frutos. Já para acerola, a separação do epicarpo e das sementes durante o processo de despolpamento ocasionou um aumento do teor de vitamina C e diminuição do teor de flavonóides na polpa. O armazenamento de polpas congeladas de morango, amora, açaí e acerola em condições comerciais (-18 ºC), por até um ano, não afeta os teores de flavonóides, vitamina C, fenólicos totais e atividade antioxidante. / The fruits become deteriorated in few days, therefore their commercialization is difficult for long distances. Thus, production of frozen fruits pulps become a favorable method for utilization of the integral fruit. The fruits containing flavonoids and ascorbic acid that are bioactive compounds that present antioxidant activity due to their ability of reducing the formation of free radicals, besides the possible effects in reducing the incidence of chronic degenerative diseases. The objective of this work was to verify the effect of the storage at commercial conditions (-18°C) of frozen fruits pulps (acerola, açaí, blackberry and strawberry) and the effect of the artisan processing on the flavonoids, vitamin C contents and antioxidant activity. Flavonoids and vitamin C contents were determined by HPLC, total phenolics contents through the Folin-Ciocalteu method, and the antioxidant activity was evaluated by the linoleic acid/&#946;-carotene system and by measuring DPPH free-radical scavenging capacity. The results showed that the effect of processing for obtainment of frozen fruits pulps on total phenolics and vitamin C changed according to the fruit analysed. The fruits pulps of strawberry and blackberry showed similar contents to their respective fruits. In acerola, epicarp and seeds separation during the processing increased the vitamin C contents and decreased the flavonoids contents in pulp. In conclusion, the storage of frozen fruits pulps of acerola, açaí, strawberry and blackberry at commercial conditions (-18ºC) during a year, did not affect the flavonoids, vitamin C, phenolics total contents and antioxidant activity.

A potencialidade do eletrodo de cobre em meio alcalino foi demonstrada para o determinação de etanol a +0,6 V vs Ag/AgCl. A participação de espécies solúveis de Cu(III) no processo eletrocatalítico envolvendo a oxidação do etanol foi demonstrada por experimentos utilizando eletrodo disco-anel. A influência do potencial de pré-tratamento no sinal anódico foi investigada e correlacionada com a morfologia dos filmes formados na superfície do eletrodo por EDS (Energy Dispersive X-Ray Spectroscopy), indicando que as espécies de Cu(III) são originadas a partir da oxidação da camada de CuO. As medidas de etanol foram realizadas por amperometria em 0,6 V (vs Ag/AgCl). A repetibilidade das medidas utilizando padrão aquoso de etanol 0,05 % (v/v) foi de 3 % (v/v) e os limites de detecção e quantificação foram de 0,005 % (v/v) e 0,01 % (v/v), respectivamente. Nas condições experimentais otimizadas, o sensor amperométrico foi utilizado para o monitoramento da concentração de etanol no ar exalado (BrAC), que foi convenientemente coletado em um balão de borracha (V = 3 L) e introduzido em uma solução de NaOH 1 mol L-1 (V = 10 mL). O sensor apresentou uma faixa linear para concentrações de etanol em ar exalado na faixa de 0,26 – 130 mg L-1, operando de acordo com os parâmetros analíticos especificados na Legislação Brasileira para a quantificação de etanol no ar exalado em condutores de veículos automotores. A constante de eliminação de etanol do corpo humano também foi investigada e os resultados concordaram com os valores da literatura. Empregando-se eletrodos de Cu e Au foram também desenvolvidas outras metodologias para a quantificação de dipirona, glicose e ácido ascórbico e sistemas em fluxo. Estudos sobre o desenvolvimento e propriedades de um sistema gerador-coletor foram realizados e o dispositivo foi utilizado em titulações de substâncias redutoras com iodo gerado eletroquimicamente. / A copper disc working electrode in alkaline solutions was demonstrated to act as a suitable amperometric sensor for ethanol determination at +0.6 V vs Ag/AgCl. The participation of free-soluble Cu(III) species in the electrocatalytic process involving the anodic oxidation of ethanol has been demonstrated by rotating ring-disc electrode voltammetry. The influence of the pretreatment potential on the anodic signal was investigated and a correlation with the morphology of the electrode surface characterized by Energy Dispersive X-Ray Spectroscopy (EDS) indicated that the Cu(III) species is originated from the oxidation of a CuO layer. Ethanol measurements were performed in the amperometric mode at 0.6 V (vs Ag/AgCl). The repeatability of the measurements for a 0.05 % aqueous ethanol solution was estimated as 3 %, and the detection and quantification limits were determined as 0.005 % and 0.01 %, respectively. At the optimum experimental conditions, the amperometric sensor was used to monitor the concentration of ethanol in breath (BrAC), which was conveniently collected in a rubber air balloon (volume = 3 L) and introduced in a 1 mol L-1 NaOH working solution (volume = 10 mL). The sensor can measure a person\'s breath ethanol over the concentration range 0.26 - 130 mg L-1 by operating it according to an established protocol, of which the analytical parameters are specified by the Brazilian Legislation for BrAC measurements in drivers. The rate of ethanol degradation in the body was followed, and the results agree with predictions in the literature. Methodologies for the determination of dipyrone, glucose and ascorbic acid were also developed by using Cu and Au electrodes. Features of a dual-band electrochemical cell were investigated towards the development of a generator-collector system, which was employed in titrations with electrogenerated iodine.

Saccharides, a class of organic materials, are potential candidates for nonlinear optical applications. Ascorbic acid is a sugar acid and is classified as a monosaccharide. The molecule of ascorbic acid has two chiral centers and, therefore, four stereoisomers. Among them, two are naturally occurring compounds; L-ascorbic acid and D-isoascorbic acid. From these two acids various salts and other derivatives could be synthesized. In this thesis, four compounds of the ascorbic acid family were selected for detailed study based on their nonlinearity, chemical and physical stability and their crystallization characteristics. The thesis is organized into seven chapters. The first chapter covers the theoretical background of nonlinear optics, especially, second harmonic generation. Second chapter details the experimental techniques and methodology adopted. Chapter 3 discusses the crystal structure, growth, physical and nonlinear optical properties of Lithium Disoascorbate monohydrate (LDAM). Detailed analysis of refractive index measurements employing Brewsters angle method and determination of phase matching curves, effective nonlinear coefficient, walk off angle etc are given. In Chapter 4, investigations on Sodium D-isoascorbate monohydrate (NDAM) are presented. Detailed characterization of the crystals including thermal, optical, dielectric properties are carried out. Analyses of dielectric dispersion based on Cole-Cole equation are discussed. Comprehensive studies on laser damage of the crystals are discussed. Chapter 5 discusses the nonlinear optical properties of the monoclinic D-isoascorbic acid (DIA). Chapter 6 presents studies on the triclinic Lithium L-ascorbate dihydrate (LLA) crystals. The crystals exhibit intense non-collinear second harmonic rings as they possesses large birefringence coupled with high second order nonlinear coefficients. The SHG conversion efficiency of these crystals is 15 times that of KDP. In the final chapter, a comprehensive summary of the work carried out is presented along with scope for further investigations.