A jabuticaba é uma fruta originalmente brasileira e que começa a ser explorada comercialmente para produção de polpa congelada, geleia, licor, dentre outros produtos. O processamento da jabuticaba gera uma grande quantidade de resíduos, oriundos da casca e da semente, que normalmente são descartados em aterros, contribuindo para poluição ambiental. Todavia, esses resíduos são ótimas fontes de ingredientes funcionais, tais como antocianinas (pigmentos roxos) e elagitaninos, ambos potentes antioxidantes. Assim, o objetivo deste estudo foi extrair o pigmento do resíduo do despolpamento da jabuticaba e caracteriza-lo; estudar o processo de secagem por atomização do pigmento;caracterizar os pós obtidos, bem como sua propriedade antioxidante e estabilidade durante o armazenamento. Para tanto, a jabuticaba foidespolpada, e do resíduo (cascas e sementes) foi obtido um extrato aquoso, o qual foi caracterizado quanto ao teor de sólidos solúveis, pH, umidade, cinzas, proteínas, lipídeos, fibras, açúcares e acidez, e, em seguida, foi desidratado em spray-dryer com os agentes carreadores maltodextrina DE10 e goma arábica. Os pós obtidos foram caracterizados quanto à umidade, higroscopicidade, cor instrumental, morfologia e tamanho das partículas, teor de antocianinas, estabilidade e propriedade antioxidante pelos métodos ORAC e DPPH, estabilidade durante estocagem e isotermas de sorção. O extrato aquoso obtido apresentou 10% de sólidos solúveis totais, pH 3,54, acidez de 0,71 g ácido cítrico/100g amostra e teor de antocianinas de 79,3 mg de antocianinas/100g de amostra. Os pós obtidos com maltodextrina em condições otimizadas apresentaram retenção média de antocianinas de 77%, umidade média de 4,0%, higroscopicidade média de 34,9 g de água absorvida/100 g de pó, rendimento médio do processo de 32,1% e em média 11,5 mg/g pó de antocianinas totais. Os valores médios para a atividade antioxidante variaram de 826,9 a 266,0 µmoles equivalentes de Trolox/g pelos métodos ORAC e DPPH, respectivamente. Já para os pós obtidos com goma arábica em condições otimizadas a retenção média de antocianinas foi de 86%, umidade média de 3,9%, higroscopicidade média de 56,1 g água absorvida/100g pó, rendimento médio do processo de 35,7% e em média 14,8 mg/g pó de antocianinas totais. Os valores médios para a atividade antioxidante variaram de 227,2 a 1152,7 µmoles equivalentes de Trolox/g de pó pelos métodos DPPH e ORAC, respectivamente. Os pós obtidos apresentaram valores altos para antocianinas, fenólicos totais e atividade antioxidante, mostrando o grande potencial do resíduo do despolpamento da jabuticaba para produção de um pigmento funcional. A presença do carreador foi efetiva para manter a estabilidade do pigmento durante a estocagem e quanto maior a sua concentração, maior a estabilidade do pigmento. / The jabuticaba is originally a Brazilian fruit and begins to be exploited commercially for the production of frozen pulp, jelly, liquor, among oth er products. The processing of jabuticaba generates a lot of waste, from the peel and seeds, which are usually discarded in landfills, contributing to environmental pollution. However, these residues are good sources of functional ingredients, such as anthocyanins (purple pigments) and elagitannins, both potent antioxidants. The objective of this study was to extract the pigment from the pulping of jabuticaba\'s waste and characterized it, to study the process of spray drying the pigment; characterize the po wders, as well as its antioxidant properties and storage stability. To this aim, jabuticaba was pulped, and the residue (peel and seeds) was obtained from an aqueous extract, which was characterized as the soluble solids, pH, moisture, ash, protein, lipid, fiber, sugars and acidity, and then was dried in a spray-dryer with agents carriers of 10 maltodextrin and gum arabic. The powders were characterized for moisture, hygroscopicity, instrumental color, morphology and particle size, anthocyanins, stability and antioxidant properties by ORAC and DPPH methods and stability during storage. The aqueous extract obtained showed 10% of total soluble solids, pH 3.54, acidity 0.71 g citric acid/100g sample and anthocyanin content of 79.3 mg anthocyanin/100g sample. The powders obtained under optimized conditions with maltodextrin showed retention of 77% anthocyanins, 4.0% of humidity, hygroscopicity of 34.9 g water absorbed/100g powder, yield of the process 32.1% and on average 11.5 mg/g of anthocyanins. The mean values for the antioxidant activity ranged from 826.9 µM Trolox equivalents/g jabuticaba\'s powder to 266.0 µM Trolox equivalents/g jabuticaba\'s powder for ORAC and DPPH methods, respectively. The gum arabic powders obtained under optimized conditions showed average retention of 86% anthocyanins, 3.9% average humidity, hygroscopicity average of 56.1 g water absorbed/100g powder, average yield of 35.7% of the process and an average of 14.8 mg/g powder anthocyanins. The mean values for the antioxidant activity ranged from 1152.7 µM Trolox equivalents/g jabuticaba\'s powder to 227.2 µM Trolox equivalents/g jabuticaba\'s powder for ORAC and DPPH methods, respectively. The powders obtained showed high concentration of anthocyanins, phenolic compounds and antioxidant activity, showing the great potential of the residue of jabuticaba\'s waste for production of a functional pigment. The presence of the carrier was effective for maintaining stability of the pigment during storage and the higher the concentration, the greater the stability of the pigment

<p>Evolution can be studied at many levels, from phenotypic to molecular, and from a variety of disciplines. An integrative approach can help provide a more complete understanding of the complexities of evolutionary change. This dissertation examines the ecology, genetics, and molecular mechanisms of the evolution of floral anthocyanin pigmentation in four species of <em>Mimulus</em> native to central Chile. Anthocyanins, which create red and purple colors in many plants, are a valuable model for studying evolutionary processes. They are ecologically important and highly variable both within and between species, and the underlying biosynthetic pathway is well characterized. The focus of this dissertation is dramatic diversification in anthocyanin coloration, in four taxa that are closely related to the genomic model system <em>M. guttatus</em>. I posed three primary questions: (1) Is floral diversification associated with pollinator divergence? (2) What is the genetic basis of the floral diversification? (3) What is the molecular mechanism of the increased production of anthocyanin pigment? The first question was addressed by evaluating patterns of pollinator visitation in natural populations of all four study taxa. The second question was explored using segregation analysis for a series of inter- and intraspecific crosses. One trait, increased petal anthocyanins in <em>M. cupreus</em>, was further dissected at the molecular level, using candidate gene testing and quantitative gene expression analysis. Pollinator studies showed little effect of flower color on pollinator behavior, implying that pollinator preference probably did not drive pigment evolution in this group. However, segregation analyses revealed that petal anthocyanin pigmentation has evolved three times independently in the study taxa, suggesting an adaptive origin. In addition to pollinator attraction, anthocyanins and their biochemical precursors protect against a variety of environmental stressors, and selection may have acted on these additional functions. Molecular analysis of petal anthocyanins in <em>M. cupreus</em> revealed that this single-locus trait maps to a transcription factor, <em>McAn1</em>, which is differentially expressed in high- versus low-pigmented flowers. Expression of the anthocyanin structural genes is tightly correlated with <em>McAn1</em> expression. The results suggest that <em>M. cupreus</em> pigmentation evolved by a mutation cis to <em>McAn1</em> that alters the intensity of anthocyanin biosynthesis.</p> / Dissertation

No description available.

Floral stripes are a common pigmentation pattern in plants. Defining the molecular mechanisms of the striped pattern formation will aid understanding of how a gene can be differentially regulated across a population of similar cells. In the venation phenotype of Antirrhinum majus, the anthocyanin pigment is typically confined to the adaxial epidermal cells overlaying the petal veins. To explore how this pattern forms this study focused on the expression and regulation of Venosa, a Myb regulator of anthocyanin biosynthesis. Pigment complementation experiments demonstrated that the lack of a MYB factor caused the lack of pigment in the cells outside the venation pigmentation domain. An allele of Venosa was isolated and identified. It was a mutant version of functional Venosa due to the central part being replaced by a transposon. Phenotype / genotype analysis indicated that the venation pigmentation patterning was due to the functional Venosa. In situ mRNA hybridisation showed that Venosa was expressed from the xylem to the adaxial epidermis, and was controlled spatially and quantitatively by a signal associated with the petal veins. Venosa expression provided the longitudinal axis for venation pigmentation stripes, and determined the location and intensity of the pigmented cells. Because another factor required for pigmentation, a bHLH factor, is specifically expressed in epidermal cells and it provides the transverse axis. The pigmented stripes are the cross expression domain of these two kinds of factors. The transcriptional controlling property of a 2.4 kb (relative to the ATG) promoter region of the Venosa gene was analysed. The -900 bp fragment was characterised in detail using 5'-end deletion mutagenesis. A heterologous host, tobacco, was used for analysis in stable transgenics. The homologous host, Antirrhinum, was used for transient assays. The efficacy and efficiency of different reporter genes (intron-containing GUS, GFP, Venosa cDNA and genomic Venosa) and enhancement systems (transcriptional enhancer, translational enhancer, inhibitor of post transcriptional gene silencing and a two-step signaling amplification system) for the detection of low-level reporter gene expression were also tested. The strength of expression correlated to the length of the promoter fragment, and expression was detected using deletions down to -500 bp, although only weak expression was found. This expression was flower specific but not vein related in both plant hosts. No expression was detected in petals of either host with fragments shorter than -500 bp. The results suggest that the fragment from -380 bp to -900 bp positively affected Venosa expression at the transcriptional level, but might not be sufficient to define venation. A possibility is that the venation controlling property is negatively controlled at the epigenetic level, such as DNA methylation status and / or chromatin structure. The role of gibberellin and sugar in the pigment and venation patterning formation of Antirrhinum was studied. The results suggest that gibberellin is not required for pigmentation or venation patterning. Convincing evidence on the role of sugar signaling could not be obtained from the experiments, due to the difficulty in separating the impact on pigmentation from other functions of sugars in petal development. In addition, the in situ analysis detected the expression of a gene probably related to aurone biosynthesis that may be a regulatory gene of this biosynthetic pathway.

Mr Albert investigated the genetic mechanisms controlling complex floral and vegetative pigmentation patterns in Petunia. He discovered two new MYB transcription factors that control the timing and spatial location of anthocyanin pigment production in flowers and leaves, giving rise to specific colour patterns. He showed that complex pigmentation patterns are formed by tightly controlling the expression of genes required to synthesise anthocyanin pigments and involves proteins that both activate genes and repress them from being expressed. The interactions between distinct classes of transcription factors form an intricate network and hierarchy, allowing fine control of gene expression and strict control of pigment production. These findings will aid in the development of ornamental plants with new pigmentation patterns and also this research serves as a model for how plants control the expression of genes to produce health-promoting plant compounds.

Mr Albert investigated the genetic mechanisms controlling complex floral and vegetative pigmentation patterns in Petunia. He discovered two new MYB transcription factors that control the timing and spatial location of anthocyanin pigment production in flowers and leaves, giving rise to specific colour patterns. He showed that complex pigmentation patterns are formed by tightly controlling the expression of genes required to synthesise anthocyanin pigments and involves proteins that both activate genes and repress them from being expressed. The interactions between distinct classes of transcription factors form an intricate network and hierarchy, allowing fine control of gene expression and strict control of pigment production. These findings will aid in the development of ornamental plants with new pigmentation patterns and also this research serves as a model for how plants control the expression of genes to produce health-promoting plant compounds.

Mr Albert investigated the genetic mechanisms controlling complex floral and vegetative pigmentation patterns in Petunia. He discovered two new MYB transcription factors that control the timing and spatial location of anthocyanin pigment production in flowers and leaves, giving rise to specific colour patterns. He showed that complex pigmentation patterns are formed by tightly controlling the expression of genes required to synthesise anthocyanin pigments and involves proteins that both activate genes and repress them from being expressed. The interactions between distinct classes of transcription factors form an intricate network and hierarchy, allowing fine control of gene expression and strict control of pigment production. These findings will aid in the development of ornamental plants with new pigmentation patterns and also this research serves as a model for how plants control the expression of genes to produce health-promoting plant compounds.

Mr Albert investigated the genetic mechanisms controlling complex floral and vegetative pigmentation patterns in Petunia. He discovered two new MYB transcription factors that control the timing and spatial location of anthocyanin pigment production in flowers and leaves, giving rise to specific colour patterns. He showed that complex pigmentation patterns are formed by tightly controlling the expression of genes required to synthesise anthocyanin pigments and involves proteins that both activate genes and repress them from being expressed. The interactions between distinct classes of transcription factors form an intricate network and hierarchy, allowing fine control of gene expression and strict control of pigment production. These findings will aid in the development of ornamental plants with new pigmentation patterns and also this research serves as a model for how plants control the expression of genes to produce health-promoting plant compounds.

Thesis (MScAgric)--Stellenbosch University, 2011. / ENGLISH ABSTRACT: Research was carried out to increase the current knowledge on sunburn development and its control in apples. In addition to its chief causes, viz. high irradiance and high temperatures, water stress has long been thought to contribute to sunburn susceptibility. Certain fruit chemical and textural characteristics have also been suspected to increase sunburn, while it is not clear how factors such as crop load affect sunburn in relation to other fruit quality parameters. In red and blushed cultivars, sunburn could be underestimated due to masking by the red colour overlay. Half and total irrigation water were withheld for two weeks in ‘Cripps’ Pink’ apples while in a concomitant trial, mulching with vermicompost (plus a thin layer of woodchips), woodchips, plant compost and black geotextile were used to regulate plant water by reducing soil evaporative loss. Sunburn increased with an increase in moisture stress. Mulching had no effect on plant water status, but it generally enhanced plant photochemistry, reducing fruit surface temperature (FST) and sunburn. Chemical and textural characteristics of exposed, but non-burned ‘Cripps’ Pink’ apples were compared with that of fruit with induced and naturally occurring sunburn. Flesh firmness, total soluble solids (TSS), and titratable acidity (TA) of induced and naturally occurring sunburnt fruit did not differ from each other, but were significantly different from the non-burnt fruit. Based on this, we concluded that sunburn induces textural and compositional changes in sunburnt fruit rather than some fruit being predisposed to develop sunburn due to their texture and chemical composition. Differences in heat stress tolerance, flesh texture and chemical composition of sun exposed and shaded fruit sides seem to relate to their light exposure history. The effect of crop load on sunburn and fruit quality were assessed on a fruit cluster level in 2008-09 and on a whole tree basis in 2009-10 in ‘Cripps’ Pink’. In 2008-09, sunburn, red colour and the proportion of first grade fruit decreased with an increase in number of fruit per cluster. Crop load did not have an effect on sunburn and fruit colour in 2009-10 although the lowest thinning severity seemed to increase sunburn severity while the proportion of first grade fruit was highest for the highest thinning severity. Fruit number per cluster had no effect on fruit size, while at the whole tree level, fruit size decreased with increasing crop load. Flesh firmness, starch breakdown, TA and TSS were neither affected by the number of fruit per cluster nor the crop load of the tree as a whole. Green ‘Granny Smith’ and ‘Golden Delicious’, blushed ‘Royal Gala’, ‘Fuji’, ‘Braeburn’ and ‘Cripps’ Pink’, and full red ‘Topred’ were used to assess how red colour (anthocyanins) masks superficial sunburn browning and bleaching. The greater reduction in superficial sunburn, but not in sunburn necrosis in red and blushed compared to green cultivars with increasing red colour a month towards harvest seemed to confirm the effect of masking. / AFRIKAANSE OPSOMMING: Hierdie navorsing is verrig ter uitbreiding van die huidige kennis oor die ontwikkeling en beheer van sonbrand in appels. Addisioneel tot die hoof oorsake van sonbrand, naamlik hoë irradiasie en hoë temperatuur, word waterstres gesien as bydraend tot sonbrandsensitiwiteit. Daar word ook vermoed dat sekere chemiese en teksturele eienskappe van die vrug sonbrand kan verhoog terwyl daar nie duidelikheid is oor hoe faktore soos oeslading sonbrand relatief tot ander vrugkwaliteitparameters kan affekteer nie. Die omvang van sonbrand in rooi en bloskultivars kan dalk onderskat word vanweë maskering deur die oorliggende rooi pigmentasie. Besproeiing is vir twee weke gehalveer of gestop in ‘Cripps’ Pink’ appels. Sonbrand het toegeneem met ‘n toename in vogstres. ‘n Deklaag van vermikompos (plus ‘n dun laag houtstukkies), houtstukkies, plantkompos en ‘n swart geotekstiel is toegedien om die plant waterstatus te reguleer deur evaporasie vanuit die grond te beperk. Die deklae het geen effek op die plant waterstatus gehad nie, maar het wel die blaar fotochemie bevorder en terselftertyd die vrugoppervlaktemperatuur verlaag en sonbrand verminder. Die chemiese en tekturele eienskappe van sonligblootgestelde ‘Cripps’ Pink’ appels sonder sonbrand is vergelyk met vrugte met geïnduseerde sonbrand en vrugte met sonbrand wat natuurlik ontwikkel het. Vrugvleisfermheid, totale oplosbare vastestowwe (TOV) en titreerbare suur (TS) van vrugte met natuurlik en geïnduseerde sonbrand het nie onderling verskil nie, maar het wel betekesnisvol verskil van vrugte sonder sonbrand. Ons het gevolglik afgelei dat sonbrand teksturele en komposisionele veranderinge teweeg bring eerder as dat sekere vrugte gepredisponeer word om sonbrand te ontwikkel vanweë hul tekstuur en chemiese samestelling. Dit kom voor dat verskille in hittestres toleransie, tekstuur en chemiese samestelling tussen die sonligblootgestelde en skadu kante van appels verband hou met hul verskil in sonligblootstelling. Die effek van oeslading op sonbrand en vrugkwaliteit in ‘Cripps’ Pink’ is ge-evalueer op trosvlak in 2008-09 en op ‘n per boom basis in 2009-10. Sonbrand, rooi kleur en die proporsie eersteklas vrugte het afgeneem met ‘n toename in die aantal vrugte per tros. Op ‘n per boom basis is rooi kleur en sonbrand egter nie deur oeslading geaffekteer nie. Die laagste vlak van vruguitdunning het wel oënskynlik die graad van sonbrand verhoog terwyl die hoogste vlak van vruguitdunning tot ‘n toename in die proporsie eersteklas vrugte gelei het. Die aantal vrugte per tros het geen effek op vruggrootte gehad nie terwyl vruggrootte afgeneem het met oeslading op ‘n heelboombasis. Vrugvleisfermheid, styselafbraak, TOV en TS is nie deur aantal vrugte per tros of die oeslading per boom geaffekteer nie. Groen ‘Granny Smith’ en ‘Golden Delicious’, rooiblos ‘Royal Gala’, ‘Fuji’, ‘Braeburn’ en ‘Cripps’ Pink’, en volrooi ‘Topred’ is gebruik om die maskering van oppervlakkige sonbrandverbruining en –verbleiking deur rooi antosianien te bestudeer. Oppervlakkige sonbrand het minder toegeneem in die maand voor oes in die rooi- en bloskultivars as in die groen kultivars terwyl vrugkleur skynbaar nie die aanwesigheid van die meer sigbare sonbrandnekrose geaffekteer het nie. Maskering speel dus ‘n rol in die aanwesigheid van sigbare sonbrand.

Made available in DSpace on 2015-06-17T19:34:19Z (GMT). No. of bitstreams: 0 Previous issue date: 2015-03-06. Added 1 bitstream(s) on 2015-06-18T12:49:04Z : No. of bitstreams: 1 000829682_20180206.pdf: 236369 bytes, checksum: b2acf7e374d9880bda3a1d28b70c3a5b (MD5) Bitstreams deleted on 2018-02-16T12:28:19Z: 000829682_20180206.pdf,. Added 1 bitstream(s) on 2018-02-16T12:29:07Z : No. of bitstreams: 1 000829682.pdf: 2233866 bytes, checksum: 6e568d064401ca32d3b1185887d5f8c4 (MD5) / Utricularia L. é um gênero cosmopolita, ausente apenas nos desertos e regiões polares, rico em espécies e altamente polimórfico em hábitos, morfologia polínica, seminal e das armadilhas. Muitas espécies do gênero possuem genomas miniaturizados, resultado de uma drástica redução de regiões não-codificadoras, dentre outras características moleculares peculiares. Utricularia amethystina é descrita como uma das mais polimórficas espécies do gênero, possui um histórico taxonômico complexo (mais de 30 sinonímias) e distribuição ampla entre as Américas. Seu polimorfismo se reflete no tamanho da planta, tamanho e forma da corola, e também na pigmentação floral - U. amethystina pode apresentar flores púrpuras (em diferentes tonalidades), amarelas e brancas - dentre outras características. O polimorfismo da pigmentação floral pode afetar a interação com o polinizador e o fluxo gênico entre os morfotipos, sendo por este motivo alvo de nosso interesse. Exploramos se o polimorfismo em caracteres seminais estaria relacionado aos morfotipos florais e buscamos características úteis para a taxonomia U. amethystina e espécies próximas. Também descrevemos as estratégias reprodutivas de Utricularia, com ênfase nos polinizadores e estratégia de polinização de U. amethystina. Além disso, investigamos o fluxo gênico entre os morfotipos florais utilizando diferentes regiões do DNA cloroplastidial previamente reportados como ―barcodes‖. E exploramos a evolução das transições de cor de flores na família Lentibulariaceae e dos genes relacionados à via de síntese das antocianinas, a principal classe de pigmentos presentes em flores e frutos. Identificamos caracteres seminais úteis para a taxonomia de Utricularia e observamos alto polimorfismo intraespecífico em U. amethystina. Utricularia amethystina, é na verdade um complexo de espécies, dentre as quais é possível encontrar fluxo gênico entre morfotipos ... / Utricularia L. is a cosmopolitan genus from Lentibulariaceae and the richest genus in species among the carnivorous plants. Its species are highly polymorphic in many traits such as habit, pollen, seed and trap morphology. Many species has a compact genome resulted from the deletion of non-coding regions, and other peculiar molecular features. Utricularia amethystina is described as one of the most polymorphic species in the genus, it has a complex taxonomic history and is found across the American continents. Its polymorphism is reflected on plant height, corolla's size and shape, and floral pigmentation - U. amethystina might show many shades of purple, yellow and white flowers. However, the most remarkable trait is the polymorphism on pigmentation of flowers, because it might undermine the pollinator attraction, and by this way interrupt the gene flow among its morphotypes. With this in mind, we have surveyed the seed traits, looking for characters useful for taxonomic purposes for U. amethystina and related species. The reproductive strategies found on the genus are also described, focusing on U. amethystina and describing its pollinator. We also have investigated the gene flow among the U. amethystina morphotypes based on barcodes regions from cpDNA. Besides this, were evaluated the evolution of genes related with the transitions on pigmentation of flowers of the Lentibulariaceae. We identified useful seed characters for the genus' taxonomy. U. amethystina is a complex with distinct lineages related one each other with high support from molecular survey with cpDNA, from which only two populations from different floral phenotypes (purple and white) were clustered in all analyses. Some lineages also showed evidences for positive selection on matK gene. The pigmentation evolution showed the expected pattern with purple flowers as the ancestral state from which the transitions occurred. We also observed that the transitions are ...