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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.
11

Encapsulation, Color Stability, and Distribution of Anthocyanins from Purple Corn (Zea mays L.), Blueberry (Vaccinium sp.), and Red Radish (Raphanus sativus) in a Cold-Setting Pectin-Alginate Gel.

Barry, Andrew Michael 29 October 2013 (has links)
No description available.
12

Evaluating the Stability of Purple Corncob Extract in Tortilla Chips

Byrnes, Nadia 09 September 2011 (has links)
No description available.
13

Impacts of Water, Extraction Procedure and Origin on Anthocyanins and Volatile Compositions of Hibiscus Extracts and Freeze-Dried Hibiscus

Ndiaye, Oumoule 05 October 2016 (has links)
There has been a lot of interest in Roselle (Hibiscus sabdariffa L.), called Bissap in Senegal, hibiscus recently because of consumer interest in nutraceutical products. However, beverages made from hibiscus have a short self-life due to anthocyanin and flavor degradation. The purpose of our study was first to assess the impacts of water, extraction procedure and origin on the anthocyanins of hibiscus extracts and secondly, to examine the impacts of freeze-drying on the anthocyanins and the volatiles compositions of hibiscus extracts. For the first experiment, a 2x3 factorial design was used with hibiscus calyces from Senegal and Egypt for the factor origin, distilled water and reformulated Dakar (Senegal) water for the second factor water, and then cold and hot extraction procedures were applied. For the second experiment, Senegalese hibiscus was extracted with hot and cold water and one part of each extract was freeze-dried. For both objectives, a ratio of 1:15 w/v (1 kilogram of calyces for 15 liters of water) were used. The time-temperature was 98°C / 30 min for hot and 22°C / 4 hours for cold extractions. The anthocyanins were determined using high performance liquid chromatography (HPLC). And the volatiles were measured using headspace-solid phase microextraction and gas chromatography-mass spectrometry (HS-SPME-GCMS). Origin and temperature as well as their interaction had significant effects on the anthocyanin contents, with respective p-values of 0.0036 and 0.0025 and 0.0002. Freeze-drying showed no effect on the anthocyanins in cold extracts. In contrast, a significant difference between the hot extract and its freeze-dried product was observed with a p-value of 0.0013. For the flavor compounds, the aroma profiles were different between cold and hot extracts and their instant powders. Globally the results of this study can help in the optimization when processing hibiscus derivatives. / MSLFS
14

Molecular analysis of red colouration in 'Bon Rouge' pear (Pyrus communis L.)

du Preez, Marlene Geraldine January 2018 (has links)
Philosophiae Doctor - PhD (Biotechnology) / The 'Bon Rouge' pear cultivar was developed from a bud mutation on a 'Bon Chretien' pear tree. The latter is characterised by green fruit skin and leaves, while 'Bon Rouge' is characterised by red leaves and red fruit skin as a result of the production of anthocyanin and other pigments. Branch forming buds on 'Bon Rouge' trees often revert to the parent phenotype producing green leaves and fruit skin. The occurrence of both phenotypes on the same tree presents a unique model to study gene expression associated with anthocyanin production in a similar genetic background under the same set of environmental condition.
15

Purple Corn (Zea mays L.) Cob Anthocyanins: Extraction, Quantification, Spray Drying and Complexation with Proteins

Lao, Fei 29 December 2016 (has links)
No description available.
16

POLYPHENOL CONTENT AND DIFFERENTIAL EXPRESSION OF FLAVONOID BIOSYNTHETIC PATHWAY GENES OF <em>FRAGARIA</em> SPP. WITH WHITE FRUIT

Roy, Sutapa 01 January 2016 (has links)
Strawberries are a rich source of polyphenols which contribute to berry color and plant disease resistance, and have been shown to lower the risk of many chronic when consumed. While a considerable body of work exists on the polyphenolic composition of commercial strawberry (Fragaria x ananassa Duch.), less information is available concerning polyphenols in Fragaria vesca, or Alpine strawberry, considered a model system for the Rosaceae family of crop species. The study of natural and genetically-engineered F. vesca mutants with white fruit can provide unique insight into regulation of metabolic flux through the complex branched phenylpropanoid/flavonoid biosynthetic pathway. Thus, the identity and quantity of major phenolic-derived anthocyanins, flavonols, flavan-3-ols, hydroxycinnamic acids, and ellagic acid (EA)-derived compounds, of red-fruited versus white-fruited genotypes of F. vesca and F. x ananassa were compared by high performance liquid chromatography-mass spectrometry. Due to the unknown origin of all but one white-fruited mutant of F. vesca, it was assumed that each resulted from independent mutation events and would exhibit different flavonoid profiles. A total of 27 phenolic-derived compounds were identified. The white genotypes of both species had very low anthocyanin levels. Total content of free EA and its conjugated forms were generally higher in white than in red F. vesca, but were the opposite in F. x ananassa, more in red than in white berries. Differences in content of individual flavonoids and in group totals among the white F. vesca genotypes suggested that they may represent different mutations affecting flavonoid production. Polyphenol profiles of a red and a white cultivar of F. vesca during four fruit developmental stages were determined along with transcriptional analyses of key structural and regulatory genes of the phenylpropanoid/ flavonoid biosynthesis. The final concentration of polyphenolic groups in red versus white F. vesca was due to the differential expression patterns of key pathway genes, especially dihydroflavonol-4-reductase, anthocyanidin synthase, and UDP-glucose-flavonoid-3-O-glucosyltransferase. The efficacy of phenolic compounds were evaluated in an in vitro study for inhibiting growth of Colletotrichum spp. associated with anthracnose fruit rot of strawberry. Only trans-cinnamic, p-coumaric, and ferulic acid inhibited isolates of the pathogen.
17

Molecular basis of anthocyanin production in callus and cell cultures of Oxalis reclinata.

Makunga, Nokwanda P. January 1996 (has links)
Oxalis reclinata Jacq., is a dicotyledonous plant. O. reclinata belongs to the family Oxalidaceae. This plant produced callus which accumulated red coloured anthocyanin pigments when cultured in vitro. The levels of anthocyanin accumulated by O. reclinata callus were higher than in the intact plant. The major pigment was isolated and identified as cyanjdin-3-glucoside (CROUCH, VAN STADEN, VAN STADEN, DREWES & MEYER, 1993). In nature, anthocyanins are responsible for orange, red, purple and blue colouration of certain tissues of higher plant s. Due to the toxicity of many synthetic red colouring agents, anthocyanins are regarded as potential substitutes for synthetic food colourants. This research was aimed at investigating mechanisms which induce pigment production as well as to optimize anthocyanin yield from callus cultures of O. reclinata, once anthocyanin production was stimulated. Pigmented and non-pigmented callus lines were generated from O. reclinata (CROUCH & VAN STADEN, 1994) and maintained on MURASHIGE & SKOOG (1962) agar medium (O.8% [w/v], pH 5.7) supplemented with 0.5 mgℓ ¯¹ BA, 5 mgℓ ¯¹ NAA, 30 gℓ ¯¹ sucrose and 0.1 gℓ ¯¹ myo-inositol. Plant tissue culture studies were conducted on red and white lines of O. reclinata to optimize callus yield and anthocyanin production in vitro. This involved manipulating contributory factors of the culture environment (carbohydrates, nitrates, phosphates, phytohormones, light and temperature). In vitro studies showed that, light played an inductive role in anthocyanin production in callus cultures of O. reclinata. The auxin, 2,4- dichlorophenoxyacetic acid (2,4-D) reduced pigment production but increased callus biomass. This hormone probably exerted its effect by reducing the pool of anthocyanin precursors, such as phenylalanine, resulting in increased primary metabolic activity. Suspension cultures were shown to be a viable means of propagating pigmented callus cells of O. reclinata. The growth curves for red and white callus cells were determined using the settled cell volume (SCV) method. Pigmented cell cultures grew for longer periods compared to nonpigmented cells of O. reclinata. White callus cells reached the stationary phase after 18 days. Red callus cells continued growing exponentially for an extra three days compared to white callus cells. The vacuole was identified as the organelle where anthocyanins accumulate using the light microscope. The molecular techniques of two-dimensional electrophoresis and in vitro translation were utilized to analyze differences in gene expression between white and red callus cultures of O. reclinata. Thus far, two-dimensional electrophoresis has shown that the red callus of O. reclinata had more polypeptides compared to the white callus. The level of gene expression was higher in the red callus compared to white callus, as revealed by nonradioactive in vitro translation. With optimization of radioactive in vitro translation, identification of specific structural anthocyanin genes which are under regulatory control should be possible. Future research should aim at acquiring a better understanding about the genetic control of anthocyanin biosynthesis in order to manipulate this pathway effectively. / Thesis (M.Sc.)-Univesity of Natal, Pietermaritzburg, 1996.
18

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]
19

Estudo químico e avaliação da atividade biológica de Eugenia brasiliensis e Eugenia involucrata (Myrtaceae)

Dametto, Alessandra Cristina [UNESP] 24 April 2014 (has links) (PDF)
Made available in DSpace on 2014-12-02T11:16:39Z (GMT). No. of bitstreams: 0 Previous issue date: 2014-04-24Bitstream added on 2014-12-02T11:21:03Z : No. of bitstreams: 1 000774869_20160430.pdf: 1068755 bytes, checksum: 6ac41fa2a6aa240b4ef5acd3caa552eb (MD5) Bitstreams deleted on 2016-03-28T13:37:50Z: 000774869_20160430.pdf,. Added 1 bitstream(s) on 2016-03-28T13:38:51Z : No. of bitstreams: 1 000774869_20160430.pdf: 781601 bytes, checksum: 120a7ad19b5aa186053d9803aa9d9b2c (MD5) Bitstreams deleted on 2016-05-04T13:08:36Z: 000774869_20160430.pdf,. Added 1 bitstream(s) on 2016-05-04T13:09:37Z : No. of bitstreams: 1 000774869.pdf: 2963190 bytes, checksum: 44be80392cfcf4ae29089c22b651c336 (MD5) / Este trabalho abordou o estudo químico e a avaliação das atividades biológicas dos extratos de folhas e frutos de Eugenia brasiliensis LAM. e Eugenia involucrata DC, espécies nativas brasileiras usadas na medicina popular para tratamento de inflamações. Nos frutos de E. brasiliensis e E. involucrata foram identificadas por CLAE-DAD-EM/EM 19 antocianinas: cianidina-3-O-soforosídeo (A1), delfinidina-3-O-laminaribiosídeo (A2), delfinidina-3-O-galactosídeo (A3), delfinidina-3-O-glicosídeo (A4), cianidina-3-O-galactosídeo (A5), cianidina-3-O-laminaribiosídeo (A6), cianidina-3-O-sambibiosídeo (A7), cianidina-3-O-cafeoil-diglicosídeo (A8), cianidina-3-O-glicosídeo (A9), cianidina-3-O-cafeoil-glicosídeo (A10), delfinidina-3-O-cumaroil-glicosídeo (A11), pelargonidina-3-O-glicosídeo (A12), cianidina-3-O-maloil-glicosídeo (A13), cianidina-3-O-acetoil-glicosídeo (A14), cianidina-3-O-pentosídeo (A15), quatro antocianinas não identificadas (A16, A17, A18 e A19) e delfinidina (A20). Com exceção de A3, A4, A5 e A9, identificadas anteriormente em E. brasiliensis, as antocianinas são relatadas pela primeira vez em ambas espécies. O teor obtido para as antocianinas majoritárias, A4 e A9, em E. brasiliensis foi 1,15 e 3,01 mg.g-1 (fruto fresco), respectivamente e em E. involucrata foi 0,58 e 2,02 mg.g-1 (fruto fresco), respectivamente. As substâncias isoladas das folhas de E. brasiliensis incluem um dissacarídeo (1), duas flavanonas: 2-(S)-7,5-di-hidroxi-6-metilflavanona (2) e 2-(S)-7,5-di-hidroxi-6,8-dimetilflavanona (3), uma di-hidrochalcona: 2’-6’-di-hidroxi-3’-metil-4’-metoxi-di-hidrochalcona (4) e uma neolignana: 7,8,7’,8’-tetra-hidro-8,8’-dimetil-3,3’-dimetoxi-4,4’-di-hidroxi-dibenzociclo-octadieno (5). As substâncias 2, 3 e 4 foram relatadas pela primeira vez na espécie em estudo e a substância 5 é inédita. Nas infusões de E. brasiliensis e E. involucrata foram identificadas 10 substâncias por EM... / This work deals with the chemical study and evaluation of biological activities of extracts from leaves and fruits of Eugenia brasiliensis LAM. and Eugenia involucrata DC, two Brazilian species used as folk medicines for treating inflammatory diseases. Nineteen anthocyanins were identified from fruits of E. brasiliensis and E. involucrata by HPLC-PDA-MS/MS: cyanidin-3-O-sophoroside (A1), delphinidin-3-O-laminaribioside (A2), delphinidin-3-O-galactoside (A3), delphinidin-3-O-glucoside (A4), cyanidin-3-O-galactoside (A5), cyanidin-3-O-laminaribioside (A6), cyanidin-3-O-sambibioside (A7), cyanidin-3-O-caffeoyl-diglucoside (A8), cyanidin-3-O-glucoside (A9), cyanidin-3-O-caffeoyl-glucoside (A10), delphinidin-3-O-coumaroyl-glucoside (A11), pelargonidin-3-O-glucoside (A12), cyanidin-3-O-maloyl-glucoside (A13), cyanidin-3-O-acetoyl-glucoside (A14), cyanidin-3-O-pentoside (A15), and four non-identified anthocyanins (A16, A17, A18 e A19) and delphinidin (A20) . Except for A3, A4, A5 and A9, which had been previously identified in E. brasiliensis, the other anthocyanis are reported here for the first time in both species. The major anthocyanins, A4 e A9, were quantified and presented yields of 1.15 and 3.01 mg.g-1 to E. brasiliensis (fresh fruit), respectively and 0.58 and 2.02 mg.g-1 to E. involucrata (fresh fruit), respectively. The isolated compounds from E. brasiliensis leaves include one dissacharide (1), two flavanones: 2(S)-7,5-dihydroxy-6-methylflavanone (2) and 2(S)-7,5-dihydroxy-6,8-dimethylflavanone (3), one dihydrochalcone: 2’,6’-dihydroxy-3’-methyl-4’-methoxy-dihydrochalcone (4) and the lignan: 7,8,7’,8’-tetrahydro-8,8’-dimethyl-3,3’-dimethoxy-4,4’-dihydroxidibenzocyclooctadiene (5). Compounds 2, 3 and 4 are reported herein for first time in this species and compound 5 is a new neolignan. Eleven compounds were identified by FIA-MS from the tea of E. brasiliensis and E. involucrata: gallic acid (C1), caffeic acid (C2)...
20

Estudo químico e avaliação da atividade biológica de Eugenia brasiliensis e Eugenia involucrata (Myrtaceae) /

Dametto, Alessandra Cristina. January 2014 (has links)
Orientador: Dulce Helena Siqueira Silva / Banca: Nivaldo Boralle / Banca: Luciana Polese / Banca: Luiz Alberto Beraldo de Moraes / Banca: Jenifer Saffi / Resumo: Este trabalho abordou o estudo químico e a avaliação das atividades biológicas dos extratos de folhas e frutos de Eugenia brasiliensis LAM. e Eugenia involucrata DC, espécies nativas brasileiras usadas na medicina popular para tratamento de inflamações. Nos frutos de E. brasiliensis e E. involucrata foram identificadas por CLAE-DAD-EM/EM 19 antocianinas: cianidina-3-O-soforosídeo (A1), delfinidina-3-O-laminaribiosídeo (A2), delfinidina-3-O-galactosídeo (A3), delfinidina-3-O-glicosídeo (A4), cianidina-3-O-galactosídeo (A5), cianidina-3-O-laminaribiosídeo (A6), cianidina-3-O-sambibiosídeo (A7), cianidina-3-O-cafeoil-diglicosídeo (A8), cianidina-3-O-glicosídeo (A9), cianidina-3-O-cafeoil-glicosídeo (A10), delfinidina-3-O-cumaroil-glicosídeo (A11), pelargonidina-3-O-glicosídeo (A12), cianidina-3-O-maloil-glicosídeo (A13), cianidina-3-O-acetoil-glicosídeo (A14), cianidina-3-O-pentosídeo (A15), quatro antocianinas não identificadas (A16, A17, A18 e A19) e delfinidina (A20). Com exceção de A3, A4, A5 e A9, identificadas anteriormente em E. brasiliensis, as antocianinas são relatadas pela primeira vez em ambas espécies. O teor obtido para as antocianinas majoritárias, A4 e A9, em E. brasiliensis foi 1,15 e 3,01 mg.g-1 (fruto fresco), respectivamente e em E. involucrata foi 0,58 e 2,02 mg.g-1 (fruto fresco), respectivamente. As substâncias isoladas das folhas de E. brasiliensis incluem um dissacarídeo (1), duas flavanonas: 2-(S)-7,5-di-hidroxi-6-metilflavanona (2) e 2-(S)-7,5-di-hidroxi-6,8-dimetilflavanona (3), uma di-hidrochalcona: 2'-6'-di-hidroxi-3'-metil-4'-metoxi-di-hidrochalcona (4) e uma neolignana: 7,8,7',8'-tetra-hidro-8,8'-dimetil-3,3'-dimetoxi-4,4'-di-hidroxi-dibenzociclo-octadieno (5). As substâncias 2, 3 e 4 foram relatadas pela primeira vez na espécie em estudo e a substância 5 é inédita. Nas infusões de E. brasiliensis e E. involucrata foram identificadas 10 substâncias por EM... / Abstract: This work deals with the chemical study and evaluation of biological activities of extracts from leaves and fruits of Eugenia brasiliensis LAM. and Eugenia involucrata DC, two Brazilian species used as folk medicines for treating inflammatory diseases. Nineteen anthocyanins were identified from fruits of E. brasiliensis and E. involucrata by HPLC-PDA-MS/MS: cyanidin-3-O-sophoroside (A1), delphinidin-3-O-laminaribioside (A2), delphinidin-3-O-galactoside (A3), delphinidin-3-O-glucoside (A4), cyanidin-3-O-galactoside (A5), cyanidin-3-O-laminaribioside (A6), cyanidin-3-O-sambibioside (A7), cyanidin-3-O-caffeoyl-diglucoside (A8), cyanidin-3-O-glucoside (A9), cyanidin-3-O-caffeoyl-glucoside (A10), delphinidin-3-O-coumaroyl-glucoside (A11), pelargonidin-3-O-glucoside (A12), cyanidin-3-O-maloyl-glucoside (A13), cyanidin-3-O-acetoyl-glucoside (A14), cyanidin-3-O-pentoside (A15), and four non-identified anthocyanins (A16, A17, A18 e A19) and delphinidin (A20) . Except for A3, A4, A5 and A9, which had been previously identified in E. brasiliensis, the other anthocyanis are reported here for the first time in both species. The major anthocyanins, A4 e A9, were quantified and presented yields of 1.15 and 3.01 mg.g-1 to E. brasiliensis (fresh fruit), respectively and 0.58 and 2.02 mg.g-1 to E. involucrata (fresh fruit), respectively. The isolated compounds from E. brasiliensis leaves include one dissacharide (1), two flavanones: 2(S)-7,5-dihydroxy-6-methylflavanone (2) and 2(S)-7,5-dihydroxy-6,8-dimethylflavanone (3), one dihydrochalcone: 2',6'-dihydroxy-3'-methyl-4'-methoxy-dihydrochalcone (4) and the lignan: 7,8,7',8'-tetrahydro-8,8'-dimethyl-3,3'-dimethoxy-4,4'-dihydroxidibenzocyclooctadiene (5). Compounds 2, 3 and 4 are reported herein for first time in this species and compound 5 is a new neolignan. Eleven compounds were identified by FIA-MS from the tea of E. brasiliensis and E. involucrata: gallic acid (C1), caffeic acid (C2)... / Doutor

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