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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.
391

Bioprospecção anti-helmíntica de geoprópolis de Melipona fasciculata Smith em testes in vitro com ovos e larvas de Haemochus contortus de pequenos ruminantes / Anthelmintic bioprospecting of Melipona fasciculata Smith geopropolis in vitro tests with eggs and larvae of Haemochus contortus of small ruminants

Batista, Marisa Cristina Aranha 22 June 2016 (has links)
Submitted by Rosivalda Pereira (mrs.pereira@ufma.br) on 2017-06-21T18:34:09Z No. of bitstreams: 1 MarisaBatista.pdf: 12168457 bytes, checksum: 713e23639a20220c99636f8a2b8cd14d (MD5) / Made available in DSpace on 2017-06-21T18:34:09Z (GMT). No. of bitstreams: 1 MarisaBatista.pdf: 12168457 bytes, checksum: 713e23639a20220c99636f8a2b8cd14d (MD5) Previous issue date: 2016-06-22 / Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPQ) / Fundação de Amparo à Pesquisa e ao Desenvolvimento Científico e Tecnológico do Maranhão (FAPEMA) / One of the main barriers to creation of goats and sheep are gastrointestinal parasites, which represent the largest and most serious health problem, reaching economically derail the creation, due to the resistance of parasites to anthelmintic drugs. Natural products, especially geopropolis produced by stingless bees of the genus Melipona, especially Melipona fasciculata Smith (tiúba) is an alternative for treatment of these diseases. Data in the literature on anthelmintic activity with geopropolis are scarce in this way, we aimed to evaluate the chemical composition of geopropolis of different phytogeographical regions, antioxidant activity and anthelmintic activity in sheep and goats, in order to obtain an anthelmintic product. The samples of geopropolis were collected in the municipalities of Palmeirândia and Fernando Falãao, MA and subjected to extraction to obtain the hydroalcoholic extracts of geopropolis. Geopropolis extracts obtained from the municipalities of Palmeirândia and Fernando Falcão, MA, were determined the total phenolic content by the Folin-Ciocalteu and antioxidant activity using the in vitro assay with 2,2-diphenyl-1-picrylhydrazyl (DPPH) and ferric reducing antioxidant power (FRAP). Extracts were derivatized and analyzed by gas chromatography-mass spectrometer (GC/MS) to identify the chemical constituents. Samples of geopropolis of different phytogeographical regions showed variations in the total phenolic content (126.60 – 847.50 mgGAE/g), and antioxidant activity antioxidante for DPPH (IC50 4.24 – 44.44 µg/mL) and FRAP (1.29 – 18.42 mmol FeII/g), the geopropolis from Fernando Falcao, showed better levels. On geopropolis from municipality of Palmeirândia were identified triterpenes cicloartane type, ursane and oleanane and phenolic acids (gallic acid and protocatechuic acid), whereas in geopropolis from Fernando Falcão, phenolic acids, gallic acid and ellagic were the main constituents. Besides the chemical identification extracts were subjected to anthelmintics in vitro larval exsheathment inhibition assay with Haemonchus contortus, with activity only the extract originating from the municipality of Fernando Falcão, and gotten a bioproduct (patent filed) when tested under the same conditions also presents action anthelmintic. This same sample from municipality of Fernando Falcão was subjected to a new extraction to obtain a higher yield, fractioned and, biomonitoring by liquid/liquid partition with solvents of different polarities, yielding fractions: hexane (HFG), chloroform (CFG), ethyl acetate (EAFG) and hydroalcoholic (HAFG). The extract and fractions were evaluated with anthelmintics in vitro assays larval exsheathment inhibition and egg hatch of Haemonchus contortus. New spectrophotometric analyzes were conducted to determine the polyphenol contents, in vitro antioxidant activity on DPPH and FRAP and chromatographic profile by high-performance liquid chromatography coupled with UV detector (HPLC/UV) and identification of the chemical components of the active fractions was performed by highperformance liquid chromatography coupled to mass spectrometry (HPLC/MS). For the egg hatch test EC50% ranged from 2.01 to 3.73 mg/ml to extract and fractions being the most active fraction EAFG with EC50 2.01 mg/ml, and exsheathment larval varied with EC50 0.12 - 0.55 mg/ml, most active fraction HAFG EC50 0.12 mg/ml. The extract and fractions showed high levels of polyphenols (64.50 - 650.19 mgGAE/g) and antioxidant activity (IC50 6.50 – 29.80 µg/mL) and FRAP (6.91 -17.19 mM Fe2+/g). The hexane fraction had low income in this way was not subject to anthelmintics tests did not show antioxidant and had the lowest concentrations of polyphenols. The active fractions were identified phenolic acid (ellagic acid and derivatives, and brevifolin carboxilate, caftaric acid), hydrolyzable tannins (gallotannins and ellagitannins). The anthelmintic activity of geopropolis of Melipona fasciculata (tiúba) is probably related to the antioxidant activity and the presence of phenolic compounds mainly phenolic acids and hydrolyzable tannins, also plant sources used by bees to produce the geopropolis contribute to the composition chemical and bioactivity of the product. / Um dos principais entraves ao crescimento da caprinovinocultura são as parasitoses gastrintestinais, que representam o maior e mais grave problema sanitário, chegando a inviabilizar economicamente a criação, em função da resistência dos parasitos aos fármacos anti-helmínticos. Os produtos naturais, especialmente a geoprópolis produzida por abelhas sem ferrão do gênero Melipona, com destaque para Melipona fasciculata Smith (tiúba) surge como uma alternativa para tratamento dessas enfermidades. Dados na literatura sobre atividade anti-helmíntica com a geoprópolis são escassos, desta forma, objetivamos avaliar a composição química da geoprópolis de diferentes regiões fitogeográficas, atividade antioxidante e atividade anti-helmíntica em caprinos e ovinos, visando a obtenção de um produto anti-helmíntico. As amostras de geoprópolis foram coletadas nos municípios de Palmeirândia e Fernando Falcão, MA e submetidas a extração para obtenção dos extratos hidroalcoólicos da geoprópolis. Dos extratos obtidos das geoprópolis oriundas dos municípios de Palmeirândia e Fernando Falcão, MA, foram determinados os teores de fenólicos totais pelo reagente de Folin−Ciocalteu, e atividade antioxidante utilizando o ensaio in vitro com o 2,2-difenil-1-picrilhidrazil (DPPH) e capacidade redutora do ferro (FRAP). Os extratos foram derivatizados e analizados por cromatografia gasosa acoplada a espectrômetro de massas (CG/EM), para identificação dos constituintes químicos. As amostras da geoprópolis oriundas das diferentes regiões fitogeográficas apresentaram variações no teor de fenólicos totais (126,60 – 847,50 mgEAG/g), atividade antioxidante para DPPH (IC50 4,24 - 44,44 µg/mL) e FRAP (1,29 – 18,42 mmol FeII/g) no entanto, as geoprópolis de Fernando Falcão, apresentaram melhores teores. Nas geoprópolis do município de Palmeirândia foram identificados, triterpenos do tipo cicloartano, ursano e oleanano e ácidos fenólicos (ácido protocatecuico e ácido gálico), enquanto que na geoprópolis de Fernando Falcão, ácidos fenólicos, ácido gálico e elágico foram os principais constituintes. Além da identificação química os extratos foram submetidos a teste anti-helmínticos in vitro de desembainhamento larvar com Haemonchus contortus, apresentando atividade apenas o extrato oriundo do município de Fernando Falcão, sendo obtido um bioproduto (patente depositada) que quando testado nas mesmas condições também apresenta ação anti-helmíntica. Essa mesma amostra oriunda do município de Fernando Falcão foi submetida a uma nova extração para obtenção de um maior rendimento, fracionada por biomonitoramento, por partição líquido/líquido com solventes de diferentes polaridades, obtendo-se frações: hexânica (HFG), clorofórmica (CFG), acetato de etila (EAFG) e hidroalcoólica (HAFG). O extrato e frações foram avaliados com testes anti-helmínticos in vitro de desembainhamento larvar e inibição da eclodibilidade de ovos de Haemonchus contortus. Novas analises espectrofotométricas foram realizadas a para determinação dos teores polifenois totais, atividade antioxidante in vitro com DPPH e FRAP e perfil cromatográfico por cromatografia líquida de alta eficiência acoplada a detector de ultravioleta (CLAE/UV) e a identificação dos componentes químicos das frações ativas foi realizada por cromatografia liquída de alta eficiência acoplada a espectrômetro de massas (CLAE/EM). Para o teste de eclodibilidade de ovos a CE50 variou de 2,01 – 3,73 mg/mL, para extrato e frações sendo a fração mais ativa EAFG com CE50 2,01 mg/mL, e o teste de desembainhamento larvar variou com CE50 de 0,12 – 0,55 mg/mL, a fração mais ativa HAFG com CE50 0,12 mg/mL. O extrato e frações apresentaram altos teores de polifenóis totais (64,50-650,19 mgEAG/g) e atividade antioxidante para DPPH (IC50 6,50 – 29,80 µg/mL) e FRAP (6,91 -17,19 mM Fe2+/g). A fração hexânica apresentou baixo rendimento desta forma não foi submetida a testes anti-helmínticos, não apresentou ação antioxidante e apresentou as menores concentrações de polifenóis. Nas frações ativas foram identificados ácido fenólicos (ácido elágico e derivados, brevifolin e ácido caftárico), taninos hidrolisáveis (galotaninos e elagitaninos). A atividade anti-helmíntica da geoprópolis de Melipona fasciculata (tiúba) provavelmente está relacionada com a atividade antioxidante e à presença de compostos fenólicos principalmente ácidos fenólicos e taninos hidrolisáveis, além disso, as fontes vegetais utilizadas pelas abelhas para a produção da geoprópolis contribuem para a composição química e bioatividade deste produto.
392

Respostas bioquímicas, físico-químicas e microbiológicas do maracujá-amarelo durante armazenamento em atmosfera modificada e em diferentes temperaturas / Biochemical, physico-chemical and microbiological responses of yellow passion fruit during storage in modified atmosphere and different temperatures

Rotili, Maria Cristina Copello 31 August 2012 (has links)
Made available in DSpace on 2017-07-10T17:37:56Z (GMT). No. of bitstreams: 1 2012_Maria_Cristina_Copello_Rotili.pdf: 1512539 bytes, checksum: 0de2ebbb956f5ea7ef24fdd44b97de82 (MD5) Previous issue date: 2012-08-31 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / The passion fruit is a climacteric fruit and at the phase of the Post harvest suffers important physiological transformations resulting of its own metabolism of ripening and others oxidative stress. The storage conditions of the passion fruit establish determining factor for its conservation. The refrigeration and modified atmosphere have been widely used in fruits, and the yellow passion fruit appears very promising in the use of these techniques, due to high instability of its physical and physiological characteristics post harvest. Therefore, this study was conducted with the objective of to evaluate the biochemical, physicochemical and microbiological of the passion fruit during its storage in modified atmosphere and at different temperatures. The work was divided into two experiments: The first consisted of the evaluation of the effect of storage temperature, where the fruits were stored at 5 º and 24 ºC. And in the second experiment evaluated the effect of modified atmosphere during the storage of the fruits at 5 °C. In both experiments the evaluations occurred at intervals of 10 days for 40 days, being evaluated the antioxidant activity DPPH and TEAC, the content of total phenolic compounds, ß-carotene and ascorbic acid, and physical and microbiological quality of the fruits. In the second experiment were included assessments of total titratable acidity, total soluble solids and enzymatic activity for polyphenol oxidase and peroxidase. In both experiments, it was utilized a completely randomized delineation, with five repetitions. The results showed that the total phenolic compounds, β-carotene and antioxidant activity of passion fruit juice were not affected by storage temperature and the content of total phenolic compounds of the juice increased with storage time. The effects of high temperature during storage were more evident in the appearance of the fruit than at the nutritional quality of the juice. The antioxidant activity of the juice, expressed in kidnapping DPPH radical, decreased during the storage, independent of temperature. Under the conditions of storage at 5 ° C and normal atmosphere, the shelf-life of passion fruit was higher and lasted up to 20 days in good conditions of marketing. The use of modified atmosphere was not able to reduce the losses of antioxidant activity of passion fruit juice during its storage. Total phenolics compounds and ascorbic acid were not affected by the use of modified atmosphere. Up to 30 days of storage there was suppressive effect of the activity of pathogens similarly in the two atmospheres of storage, suggesting that this effect was more related to low temperature. At 40 days of storage the modified atmosphere was more effective in inhibiting the activity of pathogens. The modified atmosphere was effective in reducing fresh mass loss and wrinkling of the rind, evidencing the high sensitivity of the fruit changes involving the loss of water and the importance of the use of modified atmosphere in maintaining their physical quality. Total soluble solids and total titratable acidity decreased during the storage and the modified atmosphere did not affect these results. The use of modified atmosphere during the storage at 5° C provided great conditions for marketing the yellow passion fruit up to 20 days. This study revealed the existence of activities of the polyphenoloxidase and peroxidase enzymes in the yellow passion fruit rind, but they were not identified in the fruit juice / O maracujá-amarelo é um fruto climatérico e na fase pós-colheita sofre importantes transformações fisiológicas decorrentes do próprio metabolismo de maturação e de outros estresses oxidativos. As condições de armazenamento do maracujá estabelecem fator determinante para sua conservação. A refrigeração e a atmosfera modificada têm sido largamente utilizadas em frutos, e o maracujá-amarelo se apresenta muito promissor no uso dessas técnicas, devido à elevada instabilidade de suas características físicas e fisiológicas pós-colheita. Assim, este estudo foi realizado com o objetivo de avaliar as respostas bioquímicas, físico-químicas e microbiológicas do maracujá-amarelo durante o seu armazenamento em atmosfera modificada e em diferentes temperaturas. O trabalho foi dividido em dois experimentos: O primeiro constou da avaliação do efeito da temperatura de armazenamento, onde os frutos foram armazenados em temperatura de 5º e 24ºC. E no segundo experimento foi avaliado o efeito da atmosfera modificada durante o armazenamento dos frutos a 5 ºC. Em ambos os experimentos as avaliações ocorreram em intervalo de 10 dias durante 40 dias, sendo avaliada a atividade antioxidante DPPH e TEAC, os teores de compostos fenólicos totais, ß-caroteno e ácido ascórbico e a qualidade física e microbiológica dos frutos. No segundo experimento foram incluídas as avaliações de acidez total titulável, sólidos solúveis totais e a atividade enzimática para polifenoloxidase e peroxidase. Em ambos os experimentos, foi utilizado o delineamento inteiramente casualizado, com cinco repetições. Os resultados mostraram que os compostos fenólicos totais, β-caroteno e atividade antioxidante do suco do maracujá-amarelo não foram influenciados pela temperatura de armazenagem e o conteúdo de compostos fenólicos totais do suco aumentou com o tempo de armazenagem. Os efeitos da elevada temperatura durante o armazenamento foram muito mais evidentes na aparência do fruto do que na qualidade nutricional do suco. A atividade antioxidante do suco, expressa em sequestro do radical DPPH, diminuiu durante o armazenamento, independente da temperatura. Nas condições do armazenamento a 5 ºC e em atmosfera normal, a vida-de-prateleira do maracujá-amarelo foi superior e se estendeu até 20 dias em boas condições de comercialização. O uso da atmosfera modificada não foi capaz de reduzir as perdas de atividade antioxidante do suco do maracujá-amarelo, durante o seu armazenamento. Compostos fenólicos totais e ácido ascórbico também não foram influenciados pelo uso da atmosfera modificada. Até 30 dias de armazenamento houve efeito supressor da atividade de patógenos similarmente nas duas atmosferas de armazenagem, sugerindo que este efeito esteve mais relacionado à baixa temperatura. Aos 40 dias de armazenamento a atmosfera modificada foi mais eficiente em inibir a atividade de patógenos. A atmosfera modificada foi eficaz na redução da perda de massa fresca e do enrugamento da casca, ficando evidente a alta sensibilidade dos frutos à alterações envolvendo a perda de água e a importância do uso da atmosfera modificada na manutenção da sua qualidade física. Sólidos solúveis totais e acidez total titulável diminuíram durante o armazenamento e a atmosfera modificada não influenciou estes resultados. O uso da atmosfera modificada durante o armazenamento a 5 ºC proporcionou condições ótimas para comercialização do maracujá-amarelo até 20 dias. Este estudo revelou a existência de atividade das enzimas polifenoloxidase e peroxidase na casca do maracujá-amarelo, mas não foram identificadas no suco do fruto
393

Morfoanatomia, composi??o qu?mica e atividade biol?gica do ?leo essencial de esp?cies nativas de Lippia

Oliveira, Ariana Reis Messias Fernandes de 17 December 2014 (has links)
Submitted by Ricardo Cedraz Duque Moliterno (ricardo.moliterno@uefs.br) on 2015-10-02T00:07:17Z No. of bitstreams: 1 tese_ariana_reis_17_12_2014.pdf: 4645024 bytes, checksum: bcc726ad75f2d5883fb9e1118b2a9d3d (MD5) / Made available in DSpace on 2015-10-02T00:07:17Z (GMT). No. of bitstreams: 1 tese_ariana_reis_17_12_2014.pdf: 4645024 bytes, checksum: bcc726ad75f2d5883fb9e1118b2a9d3d (MD5) Previous issue date: 2014-12-17 / The aim of this study was to characterize the morphology, production, content, chemical composition and bioactive activity of essential oils of Lippia bromleyana, Lippia lasiocalycina, Lippia insignis and Lippia thymoides, endemic species of the Bahia semi-arid. The species were grown in the Experimental Station Horto Florestal State University of Feira de Santana (UEFS) in the city of Feira de Santana - Bahia. The essential oils are extracted from dry leaves and inflorescences, by hydrodistillation in Clevenger apparatus, and chemical composition was determined by GC/MS and GC/FID. Were carried out quantitative and qualitative morphological characterizations, in addition to agronomic characterization. The leaf anatomy, types and frequency of hair were observed in binocular microscope and electronic scanning light. The antioxidant activity was assessed by the ability of the substances present in the sample capture the free radical DPPH, using five concentrations of essential oils (2, 6, 10, 14 and 18 mg mL1) and the antifungal activity by mycelium growth in vitro testing five essential oil concentrations (0.25, 0.50, 0.75, 1.0 and 1.25 ?L mL-1). In conditions where the study was conducted, it can be concluded that there are morphological differences between species in all traits, except only the number of flowers per inflorescence; there agronomic differences for all traits with L. lasiocalycina stood out in relation to the variable oil yield, while L. insignis and L. thymoides regarding the essential oil content; were identified six types of glandular trichomes one, two and tetracelular and three types of trichomes; the species L. bromleyana presents as differential anatomical absence of trichomes on the abaxial surface; L. thymoides has glandular trichomes with irregular contours on both sides, distinguishing it from other species; the frequency of trichomes on the abaxial surface is higher in species L. insignis and L. lasiocalycina, which are more anatomically similar; the major compounds found in the samples of essential oils of L. bromleyana, L. lasiocalycina, L. insignis and L. thymoides were piperitone oxide and limonene; E-ocimenona, myrcenone, myrcene, ?-myrcene and ?-cymene; thymol, myrcenone and E-ocimenona; and ?-caryophyllene, germacrene D, respectively; L. insignis and L. bromleyana stood out in relation to the antioxidant and antifungal activity, respectively. / O objetivo desse trabalho foi caracterizar a morfologia e a produ??o, teor, composi??o qu?mica e atividade bioativa de ?leos essenciais de Lippia bromleyana, Lippia lasiocalycina, Lippia insignis e Lippia thymoides, esp?cies end?micas do semi?rido baiano. As esp?cies foram cultivadas na Unidade Experimental Horto Florestal da Universidade Estadual de Feira de Santana (UEFS), na cidade de Feira de Santana ? Bahia. Os ?leos essenciais foram extra?dos de folhas e infloresc?ncias secas, por meio da hidrodestila??o em aparelho de Clevenger e a composi??o qu?mica determinada por CG/EM e CG/DIC. Foram realizadas caracteriza??es morfol?gicas quantitativas e qualitativas, al?m da caracteriza??o agron?mica. A anatomia foliar, tipos e frequ?ncia de tricomas foram observados em microsc?pio de luz binocular e eletr?nico de varredura. A atividade antioxidante foi avaliada pela capacidade das subst?ncias presentes na amostra captarem o radical livre DPPH, utilizando cinco concentra??es dos ?leos essenciais (2, 6, 10, 14 e 18 mg mL-1) e a atividade antif?ngica pelo crescimento miceliano in vitro, testando cinco concentra??es do ?leo essencial (0,25, 0,50, 0,75, 1,0 e 1,25 ?L mL-1). Nas condi??es em que foi realizado o estudo, pode-se concluir que existem diferen?as morfol?gicas entre as esp?cies em todas as caracter?sticas avaliadas, com exce??o apenas para o n?mero de flores por infloresc?ncia; existem diferen?as agron?micas para todos os caracteres avaliados, sendo que L. lasiocalycina se destacou em rela??o ? vari?vel rendimento de ?leo, enquanto que L. insignis e L. thymoides em rela??o ao teor de ?leo essencial; foram identificados seis tipos de tricomas glandulares uni, bi e tetracelular e tr?s tipos de tricomas tectores; a esp?cie L. bromleyana apresenta como diferencial anat?mico aus?ncia de tricomas tectores na face abaxial; L. thymoides possui tricomas glandulares com contornos irregulares em ambas as faces, distinguindo-a das demais esp?cies; a frequ?ncia de tricomas tectores na face abaxial ? superior nas esp?cies L. insignis e L. lasiocalycina, as quais s?o mais semelhantes anatomicamente; os compostos majorit?rios encontrados nas amostras dos ?leos essenciais de L. bromleyana, L. lasiocalycina L. insignis e L. thymoides foram: ?xido de piperitona e limoneno; E-ocimenona, mircenona, mirceno, ?-mirceno e ?-cimeno; timol, mircenona e E-ocimenona; ?-cariofileno e germacreno D, respectivamente; L. insignis e L. bromleyana se destacaram em rela??o ? atividade antioxidante e antif?ngica, respectivamente.
394

Антиоксидативна активност ферментисаних млечних производа добијених помоћу комбухе / Antioksidativna aktivnost fermentisanih mlečnih proizvoda dobijenih pomoću kombuhe / Antioxidant activity of fermented milk products obtained by means of kombucha

Vitas Jasmina 04 July 2013 (has links)
<p>У овој докторској дисертацији, комбуха је<br />култивисана на екстрактима ртањског чаја,<br />нане, коприве и мајчине душице заслађеним<br />са 7% сахарозе. Напици од комбухе добијени<br />на наведеним екстрактима су даље<br />коришћени као инокулуми за ферментацију<br />млека са 0,8; 1,6 и 2,8% млечне масти, на<br />температурама од 37, 40 и 43&deg;С.<br />Истраживање је обухватило праћење<br />антиоксидативне активности различитих<br />ферментисаних млечних производа<br />добијених помоћу комбухе, и то<br />утврђивањем способности везивања<br />слободних радикала, како веома реактивних<br />хидрокси-радикала, тако и мање реактивних,<br />стабилних 1,1-дифенил-2-пикрилхидразил<br />(DPPH) радикала. Урађена је<br />карактеризација млека, инокулума и<br />добијених производа утврђивањем физичко-<br />хемијских карактеристика, а у случају<br />производа и сензорном оценом. За млеко и<br />производе је измерен и садржај масних<br />киселина. Осим тога, одређени су и неки од<br />састојака производа за које се зна да имају<br />антиоксидативно деловање, при чему је<br />акценат стављен на витамин Це, као и<br />полинезасићене масне киселине.<br />Оптимизацијом температуре ферментације,<br />садржаја млечне масти полазног млека,<br />врсте инокулума комбухе, као и релевантних<br />састојака производа, утврђени су оптимални<br />услови за добијање најквалитетнијег<br />ферментисаног млечног производа од<br />комбухе са аспекта антиоксидативне<br />активности.</p> / <p>U ovoj doktorskoj disertaciji, kombuha je<br />kultivisana na ekstraktima rtanjskog čaja,<br />nane, koprive i majčine dušice zaslađenim<br />sa 7% saharoze. Napici od kombuhe dobijeni<br />na navedenim ekstraktima su dalje<br />korišćeni kao inokulumi za fermentaciju<br />mleka sa 0,8; 1,6 i 2,8% mlečne masti, na<br />temperaturama od 37, 40 i 43&deg;S.<br />Istraživanje je obuhvatilo praćenje<br />antioksidativne aktivnosti različitih<br />fermentisanih mlečnih proizvoda<br />dobijenih pomoću kombuhe, i to<br />utvrđivanjem sposobnosti vezivanja<br />slobodnih radikala, kako veoma reaktivnih<br />hidroksi-radikala, tako i manje reaktivnih,<br />stabilnih 1,1-difenil-2-pikrilhidrazil<br />(DPPH) radikala. Urađena je<br />karakterizacija mleka, inokuluma i<br />dobijenih proizvoda utvrđivanjem fizičko-<br />hemijskih karakteristika, a u slučaju<br />proizvoda i senzornom ocenom. Za mleko i<br />proizvode je izmeren i sadržaj masnih<br />kiselina. Osim toga, određeni su i neki od<br />sastojaka proizvoda za koje se zna da imaju<br />antioksidativno delovanje, pri čemu je<br />akcenat stavljen na vitamin Ce, kao i<br />polinezasićene masne kiseline.<br />Optimizacijom temperature fermentacije,<br />sadržaja mlečne masti polaznog mleka,<br />vrste inokuluma kombuhe, kao i relevantnih<br />sastojaka proizvoda, utvrđeni su optimalni<br />uslovi za dobijanje najkvalitetnijeg<br />fermentisanog mlečnog proizvoda od<br />kombuhe sa aspekta antioksidativne<br />aktivnosti.</p> / <p>In this PhD thesis, kombucha was cultivated on winter savory, peppermint, stinging nettle and wild thyme tea extracts, sweetened with 7% of sucrose. The kombucha beverages obtained on these extracts were used as inoculums for the fermentation of milk with 0.8; 1.6 and 2.8% milk fat, at temepratures of 37, 40 and 43&deg;С.<br />The investigation determined the antioxidant activity of different fermented milk products obtained by kombucha. The ability of free radicals (DPPH and hydroxyl) scavenging was established. The physicochemical characteristics of milk, inoculums and the obtained products were measured. The sensory analysis of the products was also performed. The content of fatty acids in milk and products was determined. The content of some of the product components with the antioxidant characteristics<br />(vitamin C and polyunsaturated fatty acids) was measured. Optimization of process temperature, milk fat content, type of kombucha inoculum, and relevant product components enabled the determination of optimum conditions for the obtaining of kombucha fermented milk products with the best quality, when the antioxidant activity is considered.</p>
395

Ekstrakcija, sastav, delovanje i moguće primene odabranih vrsta pečuraka / Extraction, content, activity and possible applications of selected mushroom species

Vidović Senka 30 May 2011 (has links)
<p>Upotrebom 50% etanola i superkritičnog ugljendioksida kao ekstragensa izvr&scaron;ena je ekstrakcija različitih vrsta pečuraka. Nakon određivanja prinosa suvih ekstrakata, u njima su određeni: sadržaj ukupnih fenola i ukupnih flavonoida, sadržaj makro- i mikro-elemenata, sadržaj adenozina, kao i sadržaj karakterističnih komponenata pistilarina i variegetične kiseline. Najveći sadržaj ukupnih fenolnih jedinjenja određen je u suvom ekstraktu pečurke <em>C. pistillaris</em>, najveći sadržaj ukupnih flavonoida u ekstraktu <em>D. confragosa</em>, a najvi&scaron;e esencijalnog cinka i selena sadrži suvi ekstrakt pečurke <em>B. edulis</em>. U odnosu na ostale suve ekstrakte ekstrakt pečurke <em>L. saccatum</em> sadrži nekoliko puta veću količinu adenozina. Antioksidativno delovanje suvih ekstrakata analizirano je primenom spektrofotometrijskih i EPR metode. Ekstrakti <em>C. pistillaris, B. edulis </em>i <em>A. mellea</em> pokazali su se kao najefikasniji skevindžeri najopasnije slobodnoradikalske vrste hidroksil radikala, dok se efikasnim u prevenciji lipidne peroksidacije mogu smatrati ekstrakti <em>B. edulis, A. mellea </em>i<em> L. saccatum</em>. Nakon određivanja prinosa supekritičnih ekstrakata ispitivanih pečuraka, u njima je analiziran sastav masnih kiselina i detektovana jedinjenja sterolnog tipa. U ispitivanim ekstraktima dominantna je nezasićena linoleinska kiselina, a značajan je udeo i oleinske nezasićene masne kiseline. Dominantno jedinjenje sterolne strukture u gotovo svim ekstraktima je ergosterol. Ispitan je uticaj superkritičnih ekstrakata pečuraka na fluidnost membrane eritrocita i na osnovu dobijenih rezultata zaključeno da bi značajnu ulogu u antihipertenzivnoj ishrani mogle imati pečurke <em>A. mellea </em>i<em> M. procera</em>.</p> / <p>Using 50% ethanol and supercritical carbon dioxide different mushroom extracts were prepared. After analysis of extraction yield, content of total phenols and total flavonoids, content of macro-elements and micro-elements, as well as content of adenosine and characteristic compounds (pistilarin and variegatic acid) were determined. Highest content od total phenols was determined in <em>C. pistillaris</em> extract, highest content of total flavonoids in<em> D. confragosa</em> and highest content of essential zinc and selenium in B. edulis dry extract. In comparsion to other extracts <em>L. saccatum</em> posses few time higher content of adenosine. Antioxidat activity was analysed by spectrophotometric and EPR methods. Extracts of <em>C. pistillaris</em>,<em> B. edulis</em> and <em>A. mellea</em> have been showed as a most efficient in scavenging of dangerous OH˙ radical. In lipid peroxidation prevention significant were mushrooms extracts of<em> B. edulis</em>, <em>A. mellea</em> and<em> L. saccatum</em>.<br />After determination of mushrooms supercritical extraction yield, fatty acid composition and sterol components were analysed. Dominant unsaturated fatty acid in investigated mushroom extracts was linoleic acid. Content of oleic fatty acid was also significant. Dominant compound of sterol structure, in almost all supercritical extracts, was ergosterole. Influence of supercritical mushroom extracts on eritrocite membrane fluidity was investigated. Acording to obtained results, mushrooms <em>A. mellea</em> and <em>M. procera</em> could have significant role in antihypertensive diet.</p>
396

Fitohemijski skrining i procena antioksidantnog i antiinflamatornog potencijala sekundarnih biomolekula u vrstama roda Plantago L. / Phytochemical screening and evaluation of antioxidant and anti-inflammatory potential of secondary metabolites of Plantago L. species

Beara (Krstić) Ivana 09 July 2010 (has links)
<p>Karakterizacija metanolnih ekstrakata jedanaest vrsta samoniklih bokvica (rod<em> Plantago L.</em>) obuhvatala je fitohemijski skrining i ispitivanje antioksidantne i antiinflamatorne aktivnosti. Primenom LC-MS/MS tehnike odreĊen je sadržaj odabranih sekundarnih biomolekula. Antioksidantna aktivnosti ekstrakata (sposobnost neutralizacije slobodnih radikala, redukcioni potencijal i inhibicija lipidne peroksidacije) ispitana je primenom spektrofotometrijskih metoda. U cilju odreĊivanja antiinflamatornog potencijala, razvijena je<em> in vitro </em>metoda za praćenje aktivnosti trombocitne ciklooksigenaze-1 i 12-lipoksigenaze. Svi ispitani ekstrakti pokazali su znaĉajnu biolo&scaron;ku aktivnost.</p> / <p>Characterization of methanol extracts of eleven<em> Plantago L.</em> species included phytochemical screening and evaluation of antioxidant and anti-inflammatory activity. The content of several secondary metabolites was determined by LC-MS/MS technique. Antioxidant activity of extracts (radical scavenger capacity, reduction potential and inhibition of lipid peroxidation) was examined by spectrophotometric methods. With the intention to evaluate anti-inflammatory activity, an<em> in vitro method</em> was developed to measure activity of platelet cyclooxygenase-1 and 12-lipoxygenase. All examined extracts showed noticeable biological activity.</p>
397

Extratos de algas marinhas como agentes antioxidantes e antimicrobianos e seus efeitos na qualidade de Minced de tilápia (Oreochromis niloticus) / Seaweeds extracts as antioxidants and antimicrobial agents and their effects on quality of tilapia Minced (Oreochromis niloticus)

Cabral, Ingridy Simone Ribeiro 04 May 2012 (has links)
A extração de Carne Mecanicamente Separada de tilápia tem se destacado como um processo atraente pela possibilidade de maior recuperação da carne após a filetagem. Porém, a separação mecânica aumenta a superfície de exposição, levando à incorporação de oxigênio e consequentemente ao \"off flavor\" devido à rancidez, tornando necessário o uso de aditivos para sua conservação. A tendência é utilizar produtos naturais como alternativas aos aditivos químicos. Entre os produtos naturais, as algas marinhas apresentam, em sua composição, metabólitos secundários com alta atividade antioxidante e antimicrobiana. Esta pesquisa teve como objetivo avaliar a composição química e a atividade biológica de quatro algas marinhas e seus efeitos, quando aplicados em Minced de tilápia. As algas Nori, Kombu, Hijiki e Wakame foram extraídas por 2 e 7 dias, em temperatura ambiente, com etanol 60, 80 e 100%. O teor de compostos fenólicos, a atividade antioxidante e a antimicrobiana in vitro foram determinados. A atividade antioxidante por métodos acelerados, Rancimat e Oxipres, também foi avaliada. As algas bioativas tiveram seu perfil químico elucidado por cromatografia líquida e gasosa. Essas algas foram aplicadas em Minced de tilápia, que, em seguida, foi armazenado a -18ºC por 180 dias. No Minced foram analisadas a composição centesimal, características de frescor por pH, BNVT e TBARS; cor instrumental, cor e aroma (de ranço) pela análise sensorial, padrões microbiológicos e composição de ácidos graxos, nos tempos 0, 60, 120 e 180 dias de armazenamento. Observou-se que a extração de 2 dias, com etanol 60%, foi a mais eficiente para extrair os compostos fenólicos. As algas Nori e Hijiki apresentaram os maiores teores desses compostos e, consequentemente, maior atividade antioxidante in vitro. Os extratos de algas não apresentaram atividade antimicrobiana contra Salmonella Enteritidis, Escherichia coli e Staphylococcus aureus. Para Klebsiella pneumoniae e Listeria monocytogenes, os extratos mais eficientes foram os extraídos com etanol 100%. As algas Nori e Hijiki foram selecionadas como as mais bioativas e submetidas aos testes de oxidação acelerada. Quando aplicadas em óleo de soja, no Rancimat, e em Minced de tilápia, no Oxipres, estas algas demonstraram efetiva atividade antioxidante. Pela cromatografia, os principais compostos identificados foram, na Nori, os ácidos clorogênico, vanílico e caféico, além dos aminoácidos alanina, glicina, valina e prolina; bem como, glicose e sorbitol. Na alga Hijiki foram detectados os ácidos clorogênico, caféico e cinâmico; alanina e prolina, bem como, xilitol e ribitol, frutose e ácido linoléico. No teste de armazenamento congelado do Minced, por 180 dias, a aplicação dos extratos de Nori e Hijiki não infuenciou na composição centesimal e pH. As algas mostraram-se eficientes no controle da produção das BNVT. No entanto, por TBARS, apesar de estarem dentro dos limites aceitáveis, as algas apresentaram comportamento pró-oxidante. Sob os aspectos microbiológicos, os minceds atenderam à legislação vigente. Sensorialmente, os provadores não detectaram diferença no \"aroma de ranço\", apenas mínimas diferenças na cor do produto. Pode-se concluir que o Minced de tilápia, adicionado de algas marinhas, manteve-se dentro dos padrões de qualidade durante o armazenamento congelado. Ressalta-se, ainda, a diferença na resposta antioxidante de acordo com o método utilizado / The extraction of minced tilapia has emerged as an attractive process due to the possibility of greater recovery of the tissue after filleting. However, mechanical separation increases the surface exposure, leading to incorporation of oxygen and consequently to the \"off-flavor\" due to rancidity, making necessary the use of additives for its preservation. The tendency is to use natural products as alternatives to chemical additives. Among the natural products, seaweeds present in its composition secondary metabolites with high antioxidant and antimicrobial activities. This research aimed to evaluate the chemical composition and biological activities of four seaweeds varieties and their effects when applied to the tilapia Minced. Nori, Kombu, Hijiki and Wakame seaweeds were extracted by 2 and 7 days, at room temperature, with ethanol 60, 80 and 100%. The phenolic content, antioxidant and antimicrobial activities in vitro were determined. The antioxidant activity by accelerated methods, Oxipres and Rancimat, were also evaluated. Seaweeds bioactive profiles were elucidated by liquid and gas chromatography. These seaweeds were applied to the tilapia Minced, that was stored at -18 °C for 180 days. The Minced were analyzed as to their composition, freshness characteristics by pH, TBARS and TVB-N, instrumental color, color and rancidity aroma by sensory analysis, microbiological standards, and fatty acid composition, at 0, 60, 120 and 180 days of storage. It was observed that the extraction after two days, with 60% ethanol, was the most efficient way to extract the phenolic compounds. Hijiki and Nori showed the highest levels of these compounds and therefore higher antioxidant activity in vitro. The extracts showed no antimicrobial activity against Salmonella Enteritidis, Escherichia coli and Staphylococcus aureus. For Klebsiella pneumoniae and Listeria monocytogenes, more efficient extracts were extracted with ethanol 100%. Hijiki and Nori seaweeds were selected as the most bioactive and submitted to accelerated oxidation tests. When applied in soy oil in the Rancimat, and tilapia Minced, in the Oxipres, these seaweeds have demonstrated effective antioxidant activity. By chromatography, the most important compounds identified were, in Nori, chlorogenic, caffeic and vanillic acids, besides the amino acids alanine, glycine, proline and valine, glucose and sorbitol. In the Hijiki seaweed, it was detected chlorogenic, caffeic and cinnamic acids, alanine and proline, as well as, ribitol and xylitol, fructose, and linoleic acid. In the test of frozen Minced storage, for 180 days, the application of Nori and Hijiki extracts did not modify neither the composition nor the pH. Seaweeds were effective in controlling the TVB-N production, but, for TBARS, although they were within acceptable limits, the seaweeds showed pro-oxidant activities. As to the microbiological aspects, the minceds complied with legal requirements. Sensorially, the tasters detected no difference in the \"rancid aroma\", only small differences in the product color. It can be concluded that the Minced tilapia, seaweed added, remained within the standards of quality during frozen storage. It should be noted, moreover, the difference in the antioxidant response, according to the method used.
398

Pressurized Liquid Extraction Of Phenolic Compounds From Fruit Pomaces

Hasbay Adil, Incinur 01 August 2006 (has links) (PDF)
In this study, extraction of phenolic compounds from sour cherry, peach and apple pomaces using high pressure extraction (HPE) and subcritical CO2 extraction (SCE) was investigated considering total phenolic content (TPC) and antiradical efficiency (AE). Different combinations of pressure (50, 125, 200 MPa), temperature (20, 40, 60&amp / #61616 / C), solid/solvent ratio (0.05, 0.15, 0.25 g/ml) and extraction time (10, 25, 40 min) were used for HPE according to the Box-Behnken experimental design. The variables used for SCE were pressure (20, 40, 60 MPa), temperature (40, 50, 60&amp / #61616 / C), ethanol concentration (14, 17, 20 wt%) and extraction time (10, 25, 40 min). For HPE, TPC and AE at the optimum conditions were 3.80 mg gae/g sample and 22 mg DPPH&amp / #729 / /g sample for sour cherry pomace, 0.93 mg gae/g sample and 6.40 mg DPPH&amp / #729 / /g sample for peach pomace and 2.08 mg gae/g sample and 10.80 mg DPPH&amp / #729 / /g sample for apple pomace, respectively. For SCE, TPC and AE at the optimum conditions were 0.60 mg gae/g sample and 2.30 mg DPPH&amp / #729 / /g sample for sour cherry pomace, 0.26 mg gae/g sample and 1.50 mg DPPH&amp / #729 / /g sample for peach pomace and 0.47 mg gae/g sample and 3.30 mg DPPH&amp / #729 / /g sample for apple pomace, respectively. Efficiency of HPE and SCE methods was compared with solvent extraction (SE). TPC and AE of the extracts obtained by HPE were close to those obtained by SE but the efficiency of SCE was low compared to HPE and SE. SCE was a better extraction method for apple and peach pomaces compared to sour cherry pomace.
399

Grape Juice Filtration, Thermopyhsical Properties Of Clear Fruit Juices And Pressurized Low Polarity Water (plpw) Extraction Of Polyphenolic Compounds From Grape Canes

Karacabey, Erkan 01 September 2009 (has links) (PDF)
Filtration of grape juice was investigated. Effects of process parameters of filtration were examined. The usage of precoating material and filter aid were found to be necessary to prolong the filter life. Filter cake was found to be incompressible with the effect of increasing pressure. Increase in temperature caused increase in flow rate due to the reduction in viscosity. The influences of depectinization and clarification on filtration process were also examined. Depectinization and clarification decreased the resistance and increased the flow rate. Improvement in the quality of the grape juice was observed when these pretreatments were employed. The effects of temperature and soluble solid concentration on physical properties of clarified fruit juices were investigated. High temperature and soluble solid content dependencies of density, viscosity and heat capacity were detected. Experimental data were fitted as a function of temperature and soluble solid content. Models being valid for studied clarified fruit juices were achieved for density and viscosity with the regression coefficients (R2) higher than 0.90. Optimization of the solid-liquid extraction conditions for trans-resveratrol, trans-&amp / #949 / -viniferin, ferulic acid, and total phenolics from milled grape canes has been investigated. Temperature and ethanol concentration were found to be major process variables for all responses. Maximum yields of trans-resveratrol, trans-&amp / #949 / -viniferin, ferulic acid, and total phenolics were predicted as 4.25 mg/g dw, 2.03 mg/g dw, 1.05 mg/g dw, and 9.28 mg/g dw, respectively. Optimization of extraction conditions for antioxidant activity of grape cane extracts measured by the Trolox equivalent antioxidant capacity (TEAC) and the oxygen radical absorbance capacity (ORACFL) assays was carried out using solid-liquid extraction and response surface methodology. Ethanol concentration and temperature employed for the extraction of antioxidant agents from grape cane samples were found to be statistically significant process variables affecting antioxidant activity measured by the TEAC and ORAC methods. trans-Resveratrol and trans-&amp / #949 / -viniferin were extracted from milled grape canes using pressurized low polarity water (PLPW). The extraction temperature was significant for both compounds: extraction at 160oC resulted in a 40% loss of trans-resveratrol compared to 95oC while reduction of trans-&amp / #949 / -viniferin at both temperatures remained at 30%. Increasing ethanol concentration from 0 to 25% increased the extraction of total phenolics and trans-&amp / #949 / -viniferin by 44% and 489%, respectively. Solvent flow rate also influenced trans-&amp / #949 / -viniferin extraction. Effective diffusivities of trans-resveratrol increased by three times with increasing temperature. The modified Gompertz equation satisfactorily explained the extraction of the stilbenes investigated.
400

Skysčių chromatografijos pokolonėlinių metodų optimizavimas augalinių antioksidantų tyrimams / Optimization of liquid chromatography post-column assays for analysis of herbal antioxidants

Raudonis, Raimondas 18 September 2012 (has links)
Vaistinių augalinių žaliavų ir fitopreparatų antioksidantinio aktyvumo tyrimams būtina taikyti optimizuotus ESC pokolonėlinius metodus bei validuoti jų metodikas, kurios leistų patikimai, tiksliai bei atkartojamai įvertinti antioksidantų sudėtį, pasiskirstymą ir stabilumą. Darbo tikslas – nuodugniai ištirti ir pritaikyti ESC pokolonėlinius metodus augalinių antioksidantų tyrimams, augalinės žaliavos ekstraktų bei jų preparatų antioksidantų sudėties ir aktyvumo įvertinimui. Nustatyta, kad reakcijos kilpos parametrai turi įtakos smailės aukščio ir bazinės linijos triukšmo santykiui. Atliktų validacijos eksperimentų rezultatai patvirtina ESC-DPPH ir ESC-ABTS pokolonėlinių metodų tinkamumą radikalus surišančių junginių nustatymui ir kiekiniam antiradikalinio aktyvumo įvertinimui. Optimizuotas ESC-FRAP pokolonėlinis metodas tinkamas kompleksiniuose mišiniuose esančių junginių redukcinių savybių nustatymui ir kiekiniam redukcinio aktyvumo įvertinimui. Nustatyti pagrindiniai antiradikalinio ir/arba redukcinio aktyvumo žymenys: Crataegus L. – chlorogeno rūgštis ir hiperozidas; Origanum L. ir Perilla L. – rozmarino rūgštis; Achillea L. – chlorogeno rūgštis ir 3,5-dikafeoilchino rūgštis; Fragaria L. – epigalokatechino galatas. Šie žymenys tinkami antioksidantinius junginius kaupiančių vaistinių augalinių žaliavų bei fitopreparatų kokybės kontrolei. / A study of antioxidant activity in medicinal herbal raw materials and phytopreparations requires the application of optimized HPLC post-column assays as well as validation of their methodologies that could allow for a reliable, accurate and reproducible evaluation of composition, distribution and stability of antioxidants. The aim of the work is to examine HPLC post-column assays and adjust them for research on plant antioxidants as well as assessment of composition and activity of herbal raw material extracts and their preparations. It was determined that reaction coil parameters have impact on the ratio of peak height and baseline noise. Evaluated validation results confirm the suitability of HPLC-DPPH and HPLC-ABTS post-column assays for the determination of radical scavenging compounds and quantitative evaluation of antiradical activity. Optimized HPLC-FRAP post-column assay can be applied for discriminating reducing active compounds in complex mixtures and quantitative evaluation of their reducing activity. Main radical scavenging and/or reducing activity markers were determined: Chlorogenic acid and Hyperoside for Crataegus L., Rosmarinic acid for Origanum L. and Perilla L., Chlorogenic acid and 3,5-dicaffeoylquinic acid for Achillea L., Epigallocatechin gallate for Fragaria L. These markers are applicable for the quality control of the herbal raw materials and phytopreparations containing antioxidants.

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