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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
1

Lietuvoje augančių gervuogių vaisių fitocheminės sudėties įvairovės tyrimas / Phytochemical composition diversity assay of blackberry fruits growing in Lithuania

Šlajūtė, Jolanta 30 June 2014 (has links)
Šio tyrimo tikslas yra įvertinti gervuogių (Rubus caesius L. ir Rubus nessensis Hall.) vaisių antocianinų sudėtį ir jos įvairavimą skirtingu nokimo metu bei vaisių ekstraktų antiradikalinį aktyvumą. Vienas iš tyrimo objektų yra dviejų skirtingų Rubus genties atstovų (Rubus caesius L. ir Rubus nessensis Hall.) vaisiai, kurie buvo renkami periodiškai kas savaitę nuo pat vaisių derėjimo pradžios, Šilutės rajone. Nustačius optimalias ekstrahavimo sąlygas, vaisių etanoliniai ekstraktai buvo tiriami spektrofometrijos metodu bei nustatomas ekstraktų antiradikalinis aktyvumas, atliekant fotometrinius 2,2-difenil-1-pikrilhidrazilo (DPPH) bei 2,2’-azino-bis-(3-etilbenztiazolin-6-sulfono rūgšties) (ABTS) radikalo katijono sujungimo metodus, o gauti rezultatai vertinami remiantis pagal tai, kurią nokimo savaitę buvo renkami vaisių mėginiai. Antrasis tyrimo objektas – R.caesius L. vaisiai, surinkti iš įvairių Lietuvos vietovių, kurių etanolinių ekstraktų sudėtyje esantis antocianinų suminis kiekis taip pat buvo vertinamas spektrofotometrijos metodu, tačiau šioje tyrimo dalyje buvo siekiama nustatyti antocianinų sudėties įvairavimą priklausomai nuo gervuogių vaisių rinkimo vietovės. Tyrimo rezultatai. Nustatyta, jog iš dviejų tirtų gervuogių rūšių, gausesne antocianinų frakcijos sudėtimi pasižymi R. caesius L. vaisių ekstraktai, kuriuose antocianinų kiekis siekė nuo 4,16 proc. iki 4,89 proc. sausoje žaliavos masėje. Atitinkamai R. nessensis Hall. vaisių ekstraktuose nustatyta antocianinų... [toliau žr. visą tekstą] / The objective of this study is to evaluate the blackberry (Rubus caesius L and Rubus nessensis Hall.) fruit’s anthocyanin composition and its variation during different ripening time and also to measure the antiradical activity in fruit extracts. One of the objects of the study is two different Rubus genus (Rubus caesius L. and Rubus nessensis Hall.) fruits, which were collected weekly from the beginning of fruit bearing in Šilutė’s area. Once the optimum extraction conditions were determined, the ethanol extracts of the fruits have been investigated using spectrophotometry and their antiradical activity was investigated using photometric 2,2- diphenyl-1-picrylhydrazyl (DPPH) and 2,2 '-azine-bis-(3- ethylbenzthiazoline-6-sulfonic acid ) (ABTS) radical scavenging techniques, and the results were evaluated according to the time, when fruit samples were collected. The second object of the research - R.caesius L. fruits collected from different locations in Lithuania. The total amount of anthocyanins in the extracts was also determined using spectrophotometry, but in this part of the study the main point was to determine how the variation of anthocyanins depends on the blackberry fruit collection area. The results showed that from two studied species of blackberry, R. caesius L. fruit extracts contained a larger amount of anthocyanin’s fraction, compared to R. nessensis Hall. fruits. In R. caesius L. fruit extracts anthocyanin’s concentration ranged from 4,16 percent to 4.89... [to full text]
2

Determinação da atividade antirradicalar e da constituição química de infusões de chás / Determination of antiradical activity and chemical composition of tea infusions

Tamayose, Cinthia Indy 18 December 2014 (has links)
O chá obtido por infusão de Camellia sinensis (L.) O. Kuntze (Theaceae) contém polifenóis, principalmente catequinas e flavonóis que apresentam atividade antioxidante, atuando como sequestradores de íons metálicos ou pelo sequestro de espécies reativas de oxigênio ou de nitrogênio. A erva-mate utilizada para o preparo da bebida chimarrão é feita a partir das folhas da arvore Ilex paraguariensis (Aquifoliaceae). A bebida da erva-mate é reconhecida como uma rica fonte de substâncias antioxidante, como os ácidos fenólicos que são responsáveis pelo efeito antioxidante in vitro e in vivo da bebida. Neste trabalho foi determinada a atividade antirradicalar de infusões obtidas de diferentes chás comerciais, o chá verde orgânico (CVorg) e um composto comercial de erva mate com chá verde (M+V). Os principais constituintes químicos dos chás foram identificados por Cromatografia de Alta Eficiência (CLAE) e alguns dos constituintes foram quantificados. Dessa forma foi possível identificar em ambos os chás ao todo cinco flavonoides glicosilados, cinco ácidos clorogênicos, cinco catequinas e um alcaloide. As infusões e algumas das substâncias identificadas foram avaliadas em relação à atividade antirradicalar utilizando diferentes métodos, um colorimétrico com os radicais 2,2-difenil-1-picrilhidrazila (DPPH·) e ácido 2,2\'-azino-bis(3-etilbenzotiazolina-6-sulfônico) (ABTS·+) e um método baseado na quimiluminescência do luminol. A infusão do CVorg mostra capacidade antirradicalar elevada quando o método com o radical ABTS·+ é utilizado, com valores similares aos obtidos com o padrão trolox®. Quando dois derivados catequinas foram submetidas ao mesmo ensaio com os dois radicais, observou-se que estes apresentaram uma capacidade antirradicalar maior frente ao radical ABTS·+, sugerindo que a elevada atividade antirradicalar da infusão CVorg pode ser atribuída à presença das catequinas analisadas. No método quimiluminescente a infusão do M+V apresentou uma capacidade antirradicalar mais alta que a infusão do CVorg. O ácido 5-cafeoilquinico, um derivado do ácido clorogênico, testado no mesmo ensaio, apresentou um potencial antirradicalar maior que as catequinas. Este resultado pode sugerir que a maior capacidade antirradicalar da infusão M+V comparado com a de CVorg, quando determinada com o ensaio luminol, pode ser atribuída à presença dos derivados do ácido clorogênico, tendo em vista que esta classe de compostos não foi identificada na infusão CVorg. / Tea obtained by infusion of Camellia sinensis (L.) O. Kuntze (Theaceae) contains polyphenols, especially catechins and flavonols which exhibit antioxidant activity, acting as scavengers of metal ions or by sequestering reactive oxygen and nitrogen species. The mate herb used for brewing the mate beverage \'erva-mate\' is made from the leaves of the tree Ilex paraguariensis (Aquifoliaceae). The beverage \'erva-mate\' is known as a rich source of antioxidant substances, such as phenolic acids that are responsible for the in vitro and in vivo antioxidant effect of the beverage. In this work the antiradical activity of infusions obtained from different commercial teas, organic green tea (CVorg) and a commercial mixture of mate herb and green tea (M + V) was determined. The main chemical constituents of the teas were identified by High Performance Liquid Chromatography (HPLC) and some of the constituents quantified. Thus it was possible to identify in both teas a total number of five glycosylated flavonoids, five chlorogenic acids derivatives, five catechins and one alkaloid. The infusions and some of the identified constituents were evaluated for its antiradical activity using different methods, a colorimetric one with the stable radicals 2,2-diphenyl-1-picrylhidrazyl (DPPH·) and 2,2\'-azino-bis(3-ethylbenzothiazoline-6-sulfonico acid (ABTS·+) and an alternative method based on luminol chemiluminescence. The infusion of CVorg shows high antiradical capacity when evaluated by the method with the radical ABTS·+, with values similar to that of the standard trolox®. When two catechins derivatives were subjected to the same test with both radical, it was observed that these showed higher antiradical capacity with the radical ABTS·+, as compared to DPPH·, suggesting that the high antiradical capacity of the CVorg infusion can be attributed to the presence of analyzed catechins. With the chemiluminescence method the M+V infusion showed a higher antiradical capacity that the CVorg infusion. 5-Cafeoilquinic acid, a chlorogenic acid derivative, tested in this assay showed a higher antiradical capacity than catechins. This result might suggest that the higher antiradical capacity of the M+V infusion as compared to the CVorg, when measured with the luminol method, can be attributed to the presence of chlorogenic acid derivatives, since this class of compounds was not identified in the CVorg infusion.
3

Determinação da atividade antirradicalar e da constituição química de infusões de chás / Determination of antiradical activity and chemical composition of tea infusions

Cinthia Indy Tamayose 18 December 2014 (has links)
O chá obtido por infusão de Camellia sinensis (L.) O. Kuntze (Theaceae) contém polifenóis, principalmente catequinas e flavonóis que apresentam atividade antioxidante, atuando como sequestradores de íons metálicos ou pelo sequestro de espécies reativas de oxigênio ou de nitrogênio. A erva-mate utilizada para o preparo da bebida chimarrão é feita a partir das folhas da arvore Ilex paraguariensis (Aquifoliaceae). A bebida da erva-mate é reconhecida como uma rica fonte de substâncias antioxidante, como os ácidos fenólicos que são responsáveis pelo efeito antioxidante in vitro e in vivo da bebida. Neste trabalho foi determinada a atividade antirradicalar de infusões obtidas de diferentes chás comerciais, o chá verde orgânico (CVorg) e um composto comercial de erva mate com chá verde (M+V). Os principais constituintes químicos dos chás foram identificados por Cromatografia de Alta Eficiência (CLAE) e alguns dos constituintes foram quantificados. Dessa forma foi possível identificar em ambos os chás ao todo cinco flavonoides glicosilados, cinco ácidos clorogênicos, cinco catequinas e um alcaloide. As infusões e algumas das substâncias identificadas foram avaliadas em relação à atividade antirradicalar utilizando diferentes métodos, um colorimétrico com os radicais 2,2-difenil-1-picrilhidrazila (DPPH·) e ácido 2,2\'-azino-bis(3-etilbenzotiazolina-6-sulfônico) (ABTS·+) e um método baseado na quimiluminescência do luminol. A infusão do CVorg mostra capacidade antirradicalar elevada quando o método com o radical ABTS·+ é utilizado, com valores similares aos obtidos com o padrão trolox®. Quando dois derivados catequinas foram submetidas ao mesmo ensaio com os dois radicais, observou-se que estes apresentaram uma capacidade antirradicalar maior frente ao radical ABTS·+, sugerindo que a elevada atividade antirradicalar da infusão CVorg pode ser atribuída à presença das catequinas analisadas. No método quimiluminescente a infusão do M+V apresentou uma capacidade antirradicalar mais alta que a infusão do CVorg. O ácido 5-cafeoilquinico, um derivado do ácido clorogênico, testado no mesmo ensaio, apresentou um potencial antirradicalar maior que as catequinas. Este resultado pode sugerir que a maior capacidade antirradicalar da infusão M+V comparado com a de CVorg, quando determinada com o ensaio luminol, pode ser atribuída à presença dos derivados do ácido clorogênico, tendo em vista que esta classe de compostos não foi identificada na infusão CVorg. / Tea obtained by infusion of Camellia sinensis (L.) O. Kuntze (Theaceae) contains polyphenols, especially catechins and flavonols which exhibit antioxidant activity, acting as scavengers of metal ions or by sequestering reactive oxygen and nitrogen species. The mate herb used for brewing the mate beverage \'erva-mate\' is made from the leaves of the tree Ilex paraguariensis (Aquifoliaceae). The beverage \'erva-mate\' is known as a rich source of antioxidant substances, such as phenolic acids that are responsible for the in vitro and in vivo antioxidant effect of the beverage. In this work the antiradical activity of infusions obtained from different commercial teas, organic green tea (CVorg) and a commercial mixture of mate herb and green tea (M + V) was determined. The main chemical constituents of the teas were identified by High Performance Liquid Chromatography (HPLC) and some of the constituents quantified. Thus it was possible to identify in both teas a total number of five glycosylated flavonoids, five chlorogenic acids derivatives, five catechins and one alkaloid. The infusions and some of the identified constituents were evaluated for its antiradical activity using different methods, a colorimetric one with the stable radicals 2,2-diphenyl-1-picrylhidrazyl (DPPH·) and 2,2\'-azino-bis(3-ethylbenzothiazoline-6-sulfonico acid (ABTS·+) and an alternative method based on luminol chemiluminescence. The infusion of CVorg shows high antiradical capacity when evaluated by the method with the radical ABTS·+, with values similar to that of the standard trolox®. When two catechins derivatives were subjected to the same test with both radical, it was observed that these showed higher antiradical capacity with the radical ABTS·+, as compared to DPPH·, suggesting that the high antiradical capacity of the CVorg infusion can be attributed to the presence of analyzed catechins. With the chemiluminescence method the M+V infusion showed a higher antiradical capacity that the CVorg infusion. 5-Cafeoilquinic acid, a chlorogenic acid derivative, tested in this assay showed a higher antiradical capacity than catechins. This result might suggest that the higher antiradical capacity of the M+V infusion as compared to the CVorg, when measured with the luminol method, can be attributed to the presence of chlorogenic acid derivatives, since this class of compounds was not identified in the CVorg infusion.
4

Baccharis oblongifolia (Ruiz & Pav.) Pers. (Asteraceae): substâncias fenólicas, influência do dioicismo e atividades antirradicalar e citotóxica / Baccharis oblongifolia (Ruiz & Pav.) Pers. (Asteraceae): phenolic compounds, dioecism influence and antiradical and cytotoxic activities

Zampieri, Paulo Roberto Ferrari 26 February 2019 (has links)
Baccharis é um dos gêneros mais expressivos em Asteraceae, com 360 espécies registradas nas Américas, especialmente na América do Sul. No Brasil são 115 espécies endêmicas, cuja popularidade é difundida na medicina popular em decorrência de espécies medicinais conhecidas como carquejas, e empregadas centenariamente por seus efeitos hepatoprotetor, em desordens renais, no tratamento da diabetes, entre outros. Essas propriedades são decorrentes da elevada diversidade química do gênero, com destaque aos terpenos e compostos fenólicos. O objetivo do trabalho foi caracterizar as substâncias fenólicas presentes nas partes aéreas de Baccharis oblongifolia (Ruiz & Pav.) Pers. e determinar as atividades antirradicalar e citotóxica dos componentes, assim como contribuir na elucidação da constituição química em plantas dioicas, característica marcante do gênero estudado. Após obtenção dos extratos e fases de partição de B. oblongifolia, quinze substâncias foram identificadas através dos espectros de RMN 1H, RMN 13C e técnicas bidimensionais, ou por comparação com padrões comerciais e/ou previamente isolados pelo grupo de pesquisa. Entre os componentes foram identificados dez derivados do ácido clorogênico, os ácidos 5-cafeoilquínico, 3,4-dicafeoilquínico, 3,5-dicafeoilquínico, 4,5-dicafeoilquínico e 3,4,5-tricafeoilquínico, e seus respectivos ésteres metílicos, o ácido cafeico, e quatro flavonoides, rutina (quercetina-3-O-rutinosídeo), nicotiflorina (caempferol-3-O-rutinosídeo), quercetina-3-O-β-[2\'\'-O-(E)-cafeoil]-rutinosídeo e caempferol-3-O-β-[2\'\'-O-(E)-cafeoil]-rutinosídeo. Os dois últimos flavonoides são substâncias inéditas em literatura. As atividades antirradicalar e citotóxica foram avaliadas para todos os extratos, fases de partição e substâncias isoladas obtendo-se resultados promissores para os ensaios antirradicalares. Não houve variação qualitativa entre os metabólitos produzidos nos indivíduos dioicos de B. oblongifolia, / Baccharis is one of the most expressive genera in Asteraceae, with 360 species found in the Americas, especially in South America. In Brazil there are 115 endemic species, whose popularity is widespread in folk medicine due to medicinal species known as \"carquejas\". For centuries these plants have been used for their hepatoprotective effects, in renal disorders, in the treatment of diabetes, among others. These properties are due to the high chemical diversity found in the genus, with emphasis on terpenoids and phenolic compounds. The objectives of this work were: 1. to characterize the phenolic compounds produced by aerial parts of Baccharis oblongifolia (Ruiz & Pav.) Pers.; 2. to determine the antiradical and cytotoxic activities of the components; 3. to contribute to elucidation of the chemical constitution in dioecious plants, a remarkable characteristic of the genus. After obtaining extracts and partitioning phases from B. oblongifolia, fifteen compounds were identified through 1H NMR, 13C NMR and two-dimensional spectra, or by comparison with commercial standards and/or previously isolated compounds by our research group. Among the components, were identified ten chlorogenic acid derivatives, 5-caffeoylquinic acid, 3,4-dicaffeoylquinic acid, 3,5-dicaffeoylquinic acid, 4,5-dicaffeoylquinic acid and 3,4,5-tricaffeoylquinic acid, and their respective methyl esters, caffeic acid, and four flavonoids, rutin (quercetin-3-O-rutinoside), nicotiflorin (kaempferol-3-O-glucoside), quercetin-3-O-β-[2\'\'-(E)-caffeoyl]-rutinoside and kaempferol-3-O-β-[2\'\'-O-(E)-caffeoyl]-rutinoside. The last two flavonoids are new compounds. The antiradical and cytotoxic activities were evaluated for extracts, partition phases and isolated compounds. Promising results were obtained for the antiradical assays. There was no qualitative variation between the metabolites produced in the dioecious individuals of B. oblongifolia
5

Estudo químico e potencial antioxidante do mel e geoprópolis coletados pela abelha sem ferrão mandaçaia (Melipona mandacaia)

SILVA, Paulo Ricardo da 17 July 2015 (has links)
Submitted by (edna.saturno@ufrpe.br) on 2017-03-30T12:33:21Z No. of bitstreams: 1 Paulo Ricardo da Silva.pdf: 2807070 bytes, checksum: a396ead3497c7e6defcd09112e6c5043 (MD5) / Made available in DSpace on 2017-03-30T12:33:21Z (GMT). No. of bitstreams: 1 Paulo Ricardo da Silva.pdf: 2807070 bytes, checksum: a396ead3497c7e6defcd09112e6c5043 (MD5) Previous issue date: 2015-07-17 / ] The species of stingless bee Melipona mandacaia is popularly known as mandaçaia and is native to northeastern Brazil. This study analyzed honey and geopropolis of mandaçaia. For honey were carried out pollen, physical and chemical analysis such as moisture, pH, free acidity, hydroxymethylfurfural, ash content, reducing sugars and water activity, amino acids, minerals and antiradical activity of four samples of honey. The major phenolic constituents of honey were extracted and analyzed by High Performance Liquid Chromatography Efficiency coupled to the Diode Array Detector (HPLC-DAD). Pollen analysis showed that the dominant pollen in honey samples was the plant species Mimosa arenosa (Fabaceae / Mimosoideae) ranging from 44.4% to 61.7%. The identified flavonoids quercetin, luteolin, and kaempferol acid derivatives: 3,4-dihydroxybenzoic, 1,2-dihydroxybenzoic, caffeic, cinnamic and ferulic were quantified. All honey samples showed the amino acid proline, alanine, serine and threonine. The minerals were the predominant calcium and potassium. All honeys showed scavenging activity of free radical front to DPPH and ABTS. For geopropolis of mandaçaia was determined to botanical origin, phenolics were quantified by HPLC-DAD and the antioxidant activity was determined by testing with DPPH, ABTS and beta carotene / linoleic acid system. Pollen analysis of nine samples geopropolis showed the presence of 25 types of pollen representing fifteen families. The Senna species (Leguminoseae) was the predominant pollen in eight of the nine samples. The phenol content in the geopropolis of mandaçaia were identified as caffeic acid, coumaric acid, trans-3-hydroxycinnamic acid, 4-methoxycinnamic acid and abscisic. All samples geopropolis showed antioxidant activity, except hexanic fractions that have been inactive for the free radical DPPH. / A espécie de abelha sem ferrão Melipona mandacaia é conhecida popularmente como mandaçaia e é nativa do Nordeste brasileiro. Neste estudo foi analisado o mel e a geoprópolis da mandaçaia. Foram realizadas as análises palinológicas, físico-químicas tais como umidade, pH, acidez livre, hidroximetilfurfural, teor de cinzas, açucares redutores e atividade de água, aminoácidos, minerais e atividade antirradicalar em quatro amostras de mel. Os principais constituintes fenólicos do mel foram extraídos e analisados por Cromatografia Líquida de Alta Eficiência acoplada ao Detector de Arranjo de Diodos (CLAE-DAD). A análise palinológica mostrou que o pólen predominante nas amostras de mel foi da espécie vegetal Mimosa arenosa (Fabaceae/Mimosoideae), variando de 44,4% a 61,7%. Os flavonoides identificados quercetina, luteolina, kampferol e os derivados de ácido: 3,4-dihidroxibenzoico, 1,2-dihidroxibenzoico, cafeico, cinâmico e ferúlico foram quantificados. Todas as amostras de mel apresentaram os aminoácidos prolina, alanina, serina e treonina. Os minerais predominantes foram o cálcio e potássio. Todos os méis apresentaram atividade sequestradora de radical livre frente ao DPPH e ABTS. A origem botânica da geoprópolis da mandaçaia foi determinada e os compostos fenólicos foram quantificados por CLAE-DAD e a atividade antioxidante foi determinada pelos testes com DPPH, ABTS e o sistema beta caroteno/ácido linoleico. A análise palinológica das nove amostras de geoprópolis mostraram a presença de 25 tipos de pólen representando quinze famílias. O tipo polínico Senna (Leguminoseae) foi o predominante em oito das nove amostras analisadas. Os fenólicos presentes na geoprópolis da mandaçaia foram identificados como sendo ácidos cafeico, cumárico, trans-3-hidroxicinâmico, abscísico e 4-metoxicinâmico. Todas as amostras de geoprópolis apresentaram atividade antioxidante, exceto as frações hexânicas que foram inativas para o radical livre DPPH.
6

Propolio neetanolinio ekstrakto technologijos parinkimas ir veikliųjų medžiagų analizė / The selection of propolis non ethanolic extract technology and analysis of active substances

Jasaitytė, Jolanta 18 June 2014 (has links)
Tyrimo tikslas - parinkti neetanolinio propolio ekstrakto technologiją ir atlikti veikliųjų medžiagų analizę. Uždaviniai: nustatyti propolio koncentracijos, ekstrakcijos tirpiklių bei jų koncentracijų, ekstrakcijos laiko, temperatūros, ekstrakcijos metodo įtakas fenolinių junginių išsiskyrimui. Nustatyti propolio ekstrakto antiradikalinį aktyvumą ir flavonoidų kiekį bei efektyviosios skysčių chromatografijos metodu nustatyti propolio ekstrakte esančius cheminius junginius ir jų antiradikalinį aktyvumą. Metodika. Bendras fenolinių junginių kiekis, buvo nustatytas naudojant farmakopėjinį Folino Ciocalteu metodą pagal galo rūgšties ekvivalentą. Flavonoidų kiekis nustatytas naudojant spektrofotometrinį metodą pagal rutino ekvivalentą. Antioksidacinis aktyvumas spektrofotometriškai buvo nustatomas naudojant DPPH radikalą. Efektyviosios skysčių chromatografijos su elektrocheminiu detektoriumi būdu buvo identifikuoti fenoliniai junginiai ir nustatytas jų antiradikalinis aktyvumas. Rezultatai. Didinant propolio koncentraciją, naudojant tirpiklius didėja bendras fenolinių junginių kiekis (p<0,05). Technologiniai procesai t.y. ekstrakcijos trukmė, temperatūros padidinimas daro reikšmingą įtaką fenolinių junginių išsiskyrimui (p<0,05). Didžiausias bendras fenolinių junginių kiekis 35,60 mg/ml buvo gautas naudojant ultragarsu skatinamą ekstrakciją 10 min esant 70 ⁰C temperatūrai, ekstrakcijos tirpikliu naudojant 30 proc. makrogolio ir vandens mišinį. Šiame ekstrakte nustatytas 88,76±1... [toliau žr. visą tekstą] / The aim of survey - to select the technology of nonethanolic propolis extract and analyse the active substances. Tasks: To examine the influence of concentration, solvent and its concentration, extraction time, temperature, the extraction method on release of total phenolic compounds. Determine the radical scavenging activity and flavonoid content of propolis extract and using high performance liquid chromatography method identify active substances and its antiradical activity. Methods: Total phenolic compounds were determined by using pharmacopoeial Folin Ciocalteu method expressed in gallic acid equivalents. Flavonoids were determined using a spectrophotometric method in rutin equivalent. Radical scavenging activity was determined by spectrophotometry using DPPH radical. High performance liquid chromatography with electrochemical detection were used to identify phenolic compounds and its radical scavenging activity. Results: Increasing of propolis concentration made a significance impact on the amount of total phenolic content (p<0,05). Extraction time, increase of temperature made a significance impact on increase of the amount of total phenolic content (p<0,05). The highest amount of total phenolic compounds 35,60 mg/ml were obtained using ultrasonic induced extraction for 10 minutes at 70 ⁰ C temperature and using 30 % macrogol – water solution as solvent. The radical scavenging capacity of this extract was 88,76 ± 1,27% and amount of flavonoids were 3,89 ± 0,43 mg/ml... [to full text]
7

Potencial antioxidante de resíduo agroindustrial de goiaba

NASCIMENTO, Rosilda Josefa do 25 February 2010 (has links)
Submitted by (edna.saturno@ufrpe.br) on 2016-07-27T15:12:30Z No. of bitstreams: 1 Rosilda Josefa do Nascimento.pdf: 820295 bytes, checksum: 67cf98bba801b8144e3c20d0ea20b4ba (MD5) / Made available in DSpace on 2016-07-27T15:12:30Z (GMT). No. of bitstreams: 1 Rosilda Josefa do Nascimento.pdf: 820295 bytes, checksum: 67cf98bba801b8144e3c20d0ea20b4ba (MD5) Previous issue date: 2010-02-25 / Considering the high production of agri-industrial waste and the possibility of this material have bioactive phytochemicals, this work aimed to evaluate the antioxidant potential of the guava waste (seed) from an industry of frozen fruit pulps. Hydroacetone, hydroethanolic, hydromethanolic and aqueous extracts, obtained by sequential extraction procedure, were submitted to the determination of total phenolic and antioxidant activity in β-carotene/linoleic acid co-oxidation system and by ferric thiocyanate method and screened for their free [DPPH• (1,1-diphenyl-2-picrilhidrazil) and ABTS•+ (2,2'-azino-bis-(3- etilbenzotiazolina 6-sulfonic acid)] scavenging activity. The hydroacetone and hydromethanolic extracts exhibited the highest content of total phenolics (5317.27 and 2176.46 ag catechin equivalent mL-1, respectively), while the aqueous and hydroethanolic extracts were excluded from antioxidant analysis. Hydroacetone extract exhibited high percentage of the inhibition of oxidation (81.95%) in β-carotene/linoleic acid co-oxidation system; high percentage of the inhibition of linoleic acid peroxidation (74.32% and 80.13%at concentrations 140 and 240mg/L, respectively), good DPPH• scavenging activity (scavenging percentage >60%; low value of EC50 and TEC50, middle value of AE), and good ABTS•+ scavenging activity (875.79mM TEAC.g-1). The hydromethanolic extract exhibited low percentage of the inhibition of oxidation (38.92%) in β-carotene/linoleic acid co-oxidation system, inhibition of linoleic acid peroxidation of the 50.50% and 73.70% (at concentrations 140 and 240mg/L, respectively), DPPH• scavenging activity (scavenging percentage < 30%, high EC50 and TEC50, and low value of AE), and bad ABTS• + scavenging activity (57.16 mM TEAC.g -1). Combining of the hydroacetone extract with BHT at different concentrations, the scavenging activity and inhibition of oxidation, in β-carotene/linoleic acid co-oxidation system were similar to that BHT alone, which demonstrated synergism between them. Hydroacetone extract from guava waste (seeds) has a significant potential antioxidant since it has shown better performance in scavenging DPPH • and ABTS• + radical, important antioxidant activity in lipid emulsion system, and synergism with BHT. Thus, the agri-industrial waste from guava can be considered as alternative of natural antioxidants. / Diante da elevada produção de resíduo agroindustrial e da possibilidade deste material conter fitoquímicos bioativos, este trabalho objetivou avaliar o potencial antioxidante de resíduo de goiaba (semente) proveniente de uma indústria de polpas de frutas congeladas. Extratos hidroacetônico, hidrometanólico, hidroetanólico e aquoso, obtidos por extração sequencial, foram utilizados para quantificar o teor de fenólicos totais e determinar a atividade antioxidante em sistema da co-oxidação β-caroteno/ácido linoléico e pelo método tiocianato férrico e a capacidade de seqüestrar radicais livres [DPPH• (1,1- difenil-2-picrilhidrazil) e ABTS•+ (2,2’-azino-bis-(3-etilbenzotiazolina-6-ácido sulfônico]. Os extratos hidroacetônico e hidrometanólico exibiram os maiores teores de fenólicos totais (5.317,27 e 2.176,46ag em equivalente de catequina mL-1, respectivamente), sendo, portanto, o aquoso e hidroetanólico excluídos da avaliação do potencial antioxidante. O extrato hidroacetônico exibiu elevado percentual de inibição da oxidação (81,95%) no ensaio da co-oxidação do β-caroteno/ acido linoléico; elevado percentual de inibição da peroxidação do ácido linoléico (74,32% e 80,13%, respectivamente, nas concentraçõesde 140 e 240mg/L); boa capacidade de sequestrar o radical DPPH (percentual de sequestro >60%, baixo valor de EC50 e de TEC50, e médio EA); e o radical ABTS•+ (875,79 mM TEAC.g-1). O extrato hidrometanólico exibiu baixo percentual de inibição da oxidação (38,92%) no ensaio da co-oxidação do β-caroteno/ acido linoléico; inibição da peroxidação do ácido linoléico de 50,50% e 73,70% (nas concentrações de 140 e 240mg/L, respectivamente); e fraca capacidade de sequestrar o radical DPPH (percentual de sequestro < 30%, alto valor de EC50 e de TEC50, e baixo EA) e o radical ABTS•+(57,16 mM TEAC.g-1). Ao associar o extrato hidroacetônico com o BHT, em diferentes concentrações, o percentual de sequestro do DPPH e de inibição da oxidação, em sistema da co-oxidação β-caroteno/ácido linoléico foi semelhante ao do BHT isolado, demonstrando haver sinergismo entre eles. O extrato hidroacetônico do resíduo agroindustrial de goiaba apresenta um expressivo potencial anti-radical, uma vez que demonstrou eficiência na captura dos radicais DPPH• e ABTS•+, relevante ação antioxidante em meio lipídico, além de sinergismo com o BHT. Desta forma, o resíduo agroindustrial de goiaba surge como alternativa de antioxidante natural.
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Etudes phytochimique et biologique de plantes soudanaises : Hydnora johannis Beccari (Hydnoraceae) et Citrullus lanatus (Thunb.) Matsum. et Nakai var. citroides (Bailey) Mansf. (Cucurbitaceae) / Phytochemical and Biological Study of Sudanese Plants : Hydnora johannis Becc. (Hydnoraceae) and Citrullus lanatus (Thunb.) Matsum. et Nakai var. citroides (Bailey) Mansf. (Cucurbitaceae)

Yagi, Sakina 01 July 2011 (has links)
Différents extraits ont été préparés à partir de racines de H. johannis et différents tests biologiques ont été appliqués en vue de rechercher différentes activités. L'extrait aqueux s'est montré particulièrement actif sur Enterococcus fecalis, Staphylococcus aureus et Bacillus. Les extraits aqueux dépourvus de tanins et les tanins isolés ne présentent pas d'activité antibactérienne. L'effet synergétique des composés serait donc responsable de l'activité antibactérienne de la plante. Une activité antifongique sur Microsporum canis, une propriété antiradicalaire et une activité antiglycation ont été constatées avec les deux extraits. Une étude toxicologique de la poudre de plante et de l'extrait éthanolique sur des rats révèle une toxicité au niveau du foie et de la rate. Cinq composés ont été isolés puis identifiés. Il s'agit de 3',4',5-Trihydroxy-6,7-diméthoxyflavone ; 3,5-Dihydroxy-4,7-diméthoxy dihydroflavonol, Catéchine, Vanilline et l'acide Protocatechuic. Du stigmastérol, de l'acide oléique, de l'acide myristique et de l'acide palmitique ont été également identifiés. Le travail sur C. lanatus var. citroides a montré que l'extrait méthanolique (70%) des pulpes de fruits possède une activité contre B. subtilis, S. aureus et E. coli. Les extraits butanolique et à l'acétate d'éthyle ne sont pas toxiques contre les larves de crevettes. L'extrait butanolique possède une propriété significative antiradicalaire. Deux composés ont été isolés et identifiés. Ce sont la Cucurbitacine E 2-O-[bêta]-glucopyranoside et la Cucurbitacine L 2-O-[bêta]-glucopyranoside. Ces composés montrent une activité antibacterienne contre E. coli. La Cucurbitacine L 2-O-[bêta]-glucopyranoside possède une activité antibactérienne contre P. aeruginosa et une propriété modérée anti-radicaux libres / Different extracts were prepared from the roots of H. johannis and different biological tests were performed. Water extract exhibited significant activity against Enterococcus fecalis, Staphylococcus aureus and Bacillus. Water extract devoid from tannin or the tannin fraction did not show any antibacterial activity reflecting the synergistic property of active compounds. Both extracts showed antifungal, antiradical capacity as well as antiglycation activity. Toxicological study of the powder and ethanol extract on rats showed toxicity to the liver and kidney tissues. Five compounds were isolated namely; 3,4,5- Trihydroxy- 6,7-dimethoxy flavone ; 3,5-Dihydroxy- 4,7- dimethoxy dihydroflavonol, Catechin, Vanillin and Protocatechuic acid. Stigmasterol, Oleic acid, Myristic acid and Palmitic acid were also identified. A study on the fruit pulps of C. lanatus var. citroides revealed that the methanolic extract displayed an antibacterial activity against B. subtilis, S. aureus and E. coli. The butanolic extract showed antiradical capacity and was not toxic to brine shrimps larvae. Two compounds were isolated namely; Cucurbitacine E 2-O-[bêta]-glucopyranoside and Cucurbitacine L 2-O- [bêta] -glucopyranoside. Both compounds showed antibacterial activity against E.coli whereas, Cucurbitacine L 2-O-[bêta]-glucopyranoside showed antibacterial activity against P. aeruginosa as well as antiradical activity
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Uticaj fizičko-hemijskih karakteristika semena uljane tikve (Cucurbita pepo L.) na kvalitet i nutritivna svojstva hladno presovanog ulja / INFLUENCE OF PHYSICO-CHEMICAL CHARACTERISTICS OF PUMKIN SEED (Cucurbita pepo L.) ON THE QUALITY AND NUTRITIVE VALUE OF COLD PRESSED OIL

Rabrenović Biljana 09 February 2012 (has links)
<p style="text-align: justify; ">Hladno presovano ulje semena uljane tikve je&nbsp;proizvod specifičan za Srbiju, za razliku od zemalja u regionu koje imaju dugu tradiciju proizvodnje&nbsp;devičanskog tikvinog ulja.&nbsp;Tokom postupka hladnog presovanja sirovogosu&scaron;enog&nbsp;semena uljane tikve na pužnoj presi&nbsp;temperatura izdvojenog ulja ne prelazi 50 <sup>o</sup>C, &scaron;to se&nbsp;odražava na fizičko-hemijske, nutritivne i senzorne&nbsp;karakteristike kao i na oksidativnu stabilnost i&nbsp;antioksidativni potencijal ovog ulja.&nbsp;U cilju &scaron;to bolje karakterizacije ovog proizvoda na&nbsp;na&scaron;em trži&scaron;tu, ispitan je kvalitet hladno presovanog&nbsp;tikvinog ulja poreklom iz semena vi&scaron;e različitih&nbsp;slobodnooplodnih sorti i F1 hibrida, golosemenih i&nbsp;uljanih tikvi sa ljuskom, koje uspevaju u na&scaron;oj&nbsp;zemlji.&nbsp;Hladno presovano ulje semena tikve odlikuju&nbsp;specifične senzorne karakteristike: pored izuzetno&nbsp;blage arome, mirisa na sirovo seme tikve i ukusa&nbsp;koji podseća na meso tikve, ovo ulje se posebno&nbsp;izdvaja po boji koja je kod ispitivanog ulja bila&nbsp;svetlo-smedja do crvenkasta. Prema senzornim&nbsp;karakteristikama (naročito boji) izdvojili su se uzorci ulja poreklom iz semena austrijskih hibrida. Na&nbsp;osnovu sastava masnih kiselina ovo ulje pripada olinsko-linolnom tipu, &scaron;to ga svrstava u nutritivno&nbsp;veoma vredna biljna ulja, čemu doprinosi i visok&nbsp;sadržaj gama-tokoferola, koji je dominantan u&nbsp;tikvinom ulju. Određivanje sastava i sadržaja sterola je posebno bilo značajno kada je u pitanju hladno&nbsp;presovano tikvino ulje s obzirom da nema&nbsp;literaturnih podataka na tu temu. U ispitivanim&nbsp;uzorcima su bili dominantni delta-7 steroli, a određen je i izuzetno visok sadržaj skvalena, koji&nbsp;ima veoma važnu biolo&scaron;ku funkciju. Ispitivano ulje je posedovalo dobar antiradikalski potencijal, koji je&nbsp;bio u snažnoj linearnoj zavisnosti sa sadržajem fenolnih materija. Ulje dobijeno ekstrakcijom iz&nbsp;pogače, koja je zaostala nakon hladnog presovanja&nbsp;semena, posedovalo je veći antiradikalski potencijal&nbsp;u odnosu na hladno presovano &scaron;to je rezultat&nbsp;sadržaja fenolnih materija u većem procentu i ne&scaron;to&nbsp;nižeg sadržaja tokoferola u odnosu na hladno<br />presovano ulje.</p> / <p> Cold-pressed pumpkin oil is a product specific<br /> to Serbia, given that other countries in the<br /> region traditionally produce virgin pumpkin oil.<br /> In the process of cold pressing raw-dried<br /> pumpkin seeds by screw press, the<br /> temperature of extracted oil does not exceed<br /> 50oC, which affects physical, chemical,<br /> nutritional and sensory characteristics of this<br /> oil, as well as its oxidative stability and<br /> antiradical capacity.<br /> For the purpose of more precise<br /> characterization of this product in the domestic<br /> market, the quality of cold pressed oil from<br /> seeds of many free breeding varieties and F1<br /> hybrids &ndash; of both naked and husk seed<br /> pumpkins being grown in our country &ndash; was<br /> examined.<br /> Specific sensorial properties: light brown to<br /> reddish color, mild aroma, a smell similar to<br /> that of raw pumpkin seeds and a taste<br /> resembling that of pumpkin pulp are<br /> characteristic for this oil. As for sensory<br /> characteristics, the samples of oil from<br /> Austrian hybrid seeds, stood out. On the basis<br /> of fatty acid content, this oil belongs to the<br /> oleic-linoleic type, meaning it is a highly<br /> nutritional vegetable oil, which is also due to<br /> high levels of dominant gamma-tocopherol. Determination of the types and content of</p> <p> sterols was particularly important, given that<br /> there are no data specific to cold-pressed<br /> pumpkin oil in the literature. Delta-7 sterols are<br /> the most dominant sterols in examined oil<br /> samples and also very high content of<br /> squalene was found, which a compound with<br /> an important biological function is. The oil has<br /> an excellent antiradical capacity, showing a<br /> strong linear correlation with the amounts of<br /> phenolic compounds. Oil extracted from the<br /> cake, left over after the cold pressing of<br /> pumpkin seeds, had greater antiradical<br /> capacity than the samples of cold pressed oil,<br /> due to higher percentage of phenolic<br /> compounds and a slightly lower content of<br /> tocopherols compared to cold pressed oil.</p>
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Funkcionalne i antioksidativne osobine tropa cvekle (Beta vulgaris) / Functional and antioxidant characteristics of beetroot pomace (Beta vulgaris)

Vulić Jelena 04 September 2012 (has links)
<p>Etanolni ekstrakti tropa odabranih sorti cvekle (Detroit, Cardeal-F1, Egipatska, Bikor i Kestrel) preči&scaron;ćeni su primenom ekstrakcije na čvrstoj fazi (SPE). Sadržaj ukupnih<br />fenolnih jedinjenja, flavonoida i betalaina u preči&scaron;ćenim ekstraktima određeni su spektrofotometrijskim metodama. HPLC analizom utvrđen je kvalitativni i kvantitativni sastav fenolnih jedinjenja i betalaina ekstrakata tropa odabranih sorti cvekle. ESR spektroskopijom ispitana je antiradikalska aktivnost ekstrakata topa cvekle na stabilne DPPH i reaktivne superoksid anjon i hidroksil radikale.<br />Spektrofotometrijski je određena antioksidativna aktivnost na DPPH radikale i redukciona sposobnost po Oyaizu u ekstraktima odabranih sorti cvekle. Ispitana je in vitro<br />antiproliferativna aktivnost frakcija ekstrakata, njihovim delovanjem na rast tri histolo&scaron;ki različite humane ćelijske linije: MCF-7 (adenokarcinom dojke), HeLa (epitelni karcinom cerviksa)i MRC-5 (fetalni fibroblastni karcinom pluća). U zavr&scaron;noj fazi rada određena je antimikrobna aktivnost ekstrakata tropa odabranih sorti cvekle.</p> / <p> Beetroot (Detroit, Cardeal-F1, Egipatska, Bikor i Kestrel)<br /> pomace ethanol extracts were purified using solid phase<br /> extraction (SPE). Contents of total phenols, flavonoids and<br /> betalains in purified extracts were determined by spectrophotometric<br /> methods. HPLC analysis were used for quantitative<br /> and qualitative characterization of phenolic compounds<br /> and betalains in investigated extracts. ESR spectroscopy<br /> was used for investigation of antiradical activity of<br /> beetroot pomace extracts on stable DPPH and reactive<br /> superoxide anion and hydroxyl radicals. Antioxidant activity<br /> was determined spectrophotometrically on DPPH radicals<br /> and reducing power according to Oyaizu in the beetroot pomace<br /> extracts. Antiproliferative activity of investigated extracts<br /> was determined in vitro, testing their influence on the<br /> growth of three histologically different human cell lines:<br /> MCF-7 (breast adenocarcinoma), HeLa (cervix epithelioid<br /> carcinoma) and MRC-5 (fetal lung). Also, antimicrobial activity<br /> of beetroot pomace extracts was determined.</p>

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