Call number: LD2668 .T4 1985 M86 / Master of Science

published_or_final_version / abstract / Paediatrics and Adolescent Medicine / Doctoral / Doctor of Philosophy

The effect of frozen storage time on the composition of the cell wall polysaccharide (CWP) of muskmelon (Cucumis melo) cultivars at different stages of maturity was investigated. Changes in composition, firmness, drip loss, and color of Cantaloupe and Honey Dew melon flesh were determined at three stages of maturity and for three periods of storage at -23°C. Relationships between firmness, drip loss, and other composition measurements, as well as the total CWP sugar composition, were also determined. Cell wall polyssacharides were isolated and purified, and fractionations were performed using cyclohexane trans- 1,2-diamine tetraacetate (CDTA), Na₂C0₃, guanidinium thiocyanate (GTC), and KOH. All fractions and residues were dialysed and then freeze-dried. Following hydrolysis of CWP fractions with trifluoroacetate (TFA), the alditol acetate derivatives of neutral sugars from each CWP fraction were prepared and analyzed by gas chromatography, using myo-inositol as the internal standard. TFA insoluble fractions were analyzed colorimetrically using phenol-sulphuric acid reagent. Uronic acid was determined using 0.15% m-hydroxybiphenyl for absorbance at 520 nm with galacturonic acid as the standard. It was determined that CDTA and Na₂C0₃ fractions were composed of typical pectic materials, containing mostly galacturonic acid with the neutral sugars arabinose, galactose, rhamnose, and a smaller amount of xylose. As maturity increased, CDTA fraction yields increased, though total neutral sugar CWP compositions decreased. GTC and KOH fractions were typical of hemicellulose, and contained principally xylose, glucose, galactose, mannose, and fucose, with very small amounts of uronic acid, arabinose, and rhamnose. Residue fractions contained principally glucose and galactose, with smaller amounts of mannose, xylose, arabinose, and fucose. With the exception of xylose and glucose, all neutral sugars decreased significantly (p < 0.01) as maturity increased in both the Cantaloupe and Honey Dew melons. Total uronic acid did not change as maturity increased, except for Cantaloupe, where total uronic acid decreased from the ripe to overripe stages. The CDTA fraction yield increased and all neutral sugars decreased significantly (p < 0.05) as storage time was increased. Only the CDTA fraction yield was negatively correlated with the firmness of both melons, and was positively correlated with drip loss as maturity and frozen storage time were increased. Firmness was positively correlated with Na₂C0₃ and GTC fraction yield in Cantaloupe, whereas for Honey Dew there was no correlation between firmness and Na₂C0₃ or GTC fraction yield as maturity increased. The KOH fraction was negatively correlated with firmness in Cantaloupe, whereas there was no correlation between firmness and KOH fractions in Honey Dew existed as maturity increased. The residue fractions increased in both melons only from the underripe to the ripe stages, and did not change from ripe to overripe. Firmness was positively correlated with total rhamnose, arabinose, mannose, and galactose as maturity increased, and the drip loss was negatively correlated with all total neutral sugars as storage time was increased. During frozen storage, there was a significant decreases (p < 0.05) in total CWP sugars in relation to increased storage time. The decrease in total sugars was more dramatic during the 0 to 5 month period than the 5 to 10 month period of frozen storage. Galactose did not change in the Cantaloupe, whereas in Honey Dew it decreased 34.3% from 0 to 5 months then decreased only 13% from 5 to 10 months of storage. / Graduation date: 1994

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Les alginates sont des polysaccharides naturels extraits des algues brunes, capables de réticuler instantanément en formant un gel au contact des ions calcium. L'objet de cette thèse est d'utiliser ces alginates au sein de formulations détergentes capables de dégraisser les surfaces de matériaux composites usinés. Les solutions détergentes sont spécifiquement formulées pour être compatibles avec les alginates afin d'empêcher leur dégradation tout en permettant leur réticulation après action détergente. La faisabilité du procédé a été démontrée et ses paramètres critiques ont été identifiés et étudiés.Le principal avantage de ce procédé est qu'il permet, contrairement aux solutions de dégraissage lessivielles traditionnelles, de ne pas gaspiller d'eau tout en offrant un moyen rapide et efficace de dégraisser les surfaces. / Abstract

Thesis submitted in fulfilment of the requirements for the degree Master of Technology: Food Technology in the Faculty of Applied Sciences at the Cape Peninsula University of Technology / The aim of this study was to evaluate bambara groundnut [BGN] non-starch polysaccharides [NSP] subject to the incorporation into model and food systems with a view to establish their functional and physicochemical properties. BGN insoluble dietary fibre [BGNIF] and soluble dietary fibre [BGNSF] were successfully extracted from four varieties (black-eye: BLE, red: RED, brown: BRN and brown-eye: BRE). Physicochemical properties evaluated revealed the high bulk density of all BGNIF and BGNSF varieties, which could contribute to cost-effective packaging. The microstructures of BGNIFs were irregular in shape with different sizes. The colour parameters (lightness, redness, yellowness, chroma and hue angle) differed significantly [p ≤ 0.05] across all BGNIF and BGNSF varieties; and indicated a yellowish-red colour for BGNIFs and a light yellow colour for BGNSFs. Negligible amounts of condensed tannins [CT] were found in BGNIFs (0.014 – 0.160 mg.g-1). Higher amounts polyphenols [PP] were present in BGNSFs (45.42 – 55.90 mg.g-1 gallic acid equivalents [GAE]) compared to the amount PP in BGNIFs (6.14 – 15.56 mg.g-1 GAE). Major sugars identified were arabinose/galactose, xylose and mannose in BGNIFs, and xylose and mannose in BGNSFs. The functional properties evaluated revealed high swelling capacity of BGNIFs (6.37 – 7.72 ml.g-1) and no significant [p > 0.05] difference in water retention capacity. Fat absorption capacity ranged from 1.38 – 1.52 g oil.g-1 dry weight for BGNIFs and 4.04 – 4.55 g oil.g-1 dry weight for BGNSFs. Variability in BGNIF (91.2%) and BGNSF (79.4%) physicochemical and functional properties could both be explained by two principal components (BGNIF component 1: PP, redness, yield; and component 2: xylose, yellowness and chroma; BGNSF component 1: yellowness, chroma, mannose content; and component 2: redness, fat absorption and fructose content). Following an IV optimal mixture design, an optimum white bread formulation was obtained using 59.5% water, 4.3% yeast and 8.5% BGNIF. Bread enriched with the four BGNIF varieties (BLE, RED, BRN and BRE) were tested for several physicochemical properties. Significant [p ≤ 0.05] differences existed between the control and BGNIF enriched loaves for crumb grain characteristics (including pore area distribution, feret angle, circularity, roundness and aspect ratio). Specific loaf volume of BGNIF enriched loaves ranged from 3.33 – 3.85 ml.g-1 and were significantly [p ≤ 0.05] lower compared to the control bread (4.16 ml.g-1). Favourable texture characteristics obtained with the BGNIF enriched breads were lower hardness, chewiness and gumminess compared to the control loaf. Crust and crumb colour parameters (lightness, redness, yellowness, chroma and hue angle) were significantly [p ≤ 0.05] different across all loaves. BRE BGNIF bread (3.43 ± 0.20) had the significantly [p ≤ 0.05] lowest crumb colour difference compared to the control bread; whilst BRN (1.72 ± 0.42) and BRE (2.44 ± 0.78) loaves had the lowest significant [p ≤ 0.05] crust colour difference compared to the control. Favourable chemical properties were the high total dietary fibre [TDF] (7.14 – 8.33%) content of all BGNIF enriched loaves compared to the control loaf (4.96%). Significant [p ≤ 0.05] differences were also observed for some loaves for moisture content, condensed tannins and polyphenol content. Variability in bread physicochemical properties was differentiated by three components (component 1: bread textural properties; component 2: specific loaf volume and bread lightness; component 3: crumb colour parameters) which accounted for a cumulative variation of 92.8%. All bread loaves were also sensorially acceptable as rated moderately like to like very much (>3 rating on a 5-point hedonic scale) by consumers for all parameters (appearance, crust and crumb colour, aroma, taste, texture and overall acceptability) evaluated. Furthermore, brown BGNSF was tested for stabilising effects in an orange beverage emulsion. BGNSF and orange oil were varied at two levels each based on a 22 augmented factorial design and the effects determined on the equilibrium backscattering [BS] flux as emulsion stability indicator. The BS profiles which resulted from the Turbiscan stability analysis revealed flocculation at low rates as the major destabilisation mechanism. The optimal formulation producing a stable emulsion was identified as low oil (6%) and high BGNSF (30%) concentrations. The objective of this study was therefore achieved and showed that positive physicochemical and functional properties are associated with BGNIF and BGNSF from black-eye, red, brown and brown-eye varieties. Furthermore, the incorporation of BGN fibres in white bread and a beverage emulsion was shown to contribute positive technological properties in these systems.

Orientador: Eliana Gertrudes de Macedo Lemos / Coorientador: Tereza Cristina Luque Castellane / Banca: Maria de Lourdes Corradi Custodio da Silva / Banca: Luciana Maria Saran / Banca: Tsai Siu Mui / Banca: Jackson Antonio Marcondes de Souza / Resumo: As estruturas e alguns compostos produzidos pelos microrganismos apresentam elevada quantidade de cargas como, por exemplo, parede celular e biopolímeros. Os exopolissacarídeos (EPSs) de bactérias pertencentes à ordem Rhizobiales apresentam biopolímeros que têm sido muito estudados. Os EPSs são moléculas que apresentam grupos polares, esta característica é capaz de reduzir a tensão interfacial de mistura água/óleo e óleo/água. A formação de emulsões é um fator importante para a biodegradação de óleos e hidrocarbonetos. As cargas presentes na parede celular das células bacterianas são de natureza predominantemente aniônica. Estas estruturas são capazes de interagir fortemente com cátions metálicos e desempenham um papel importante no sequestro ou imobilização de íons no ambiente. A aplicação dos isolados de rizóbios são interessantes ferramentas biotecnológicas no processo de biorremediação, por estes microrganismos não apresentarem toxicidade à saúde e ao meio ambiente. Dos isolados de rizóbios pertencentes ao Laboratório de Bioquímica de Microrganismos e Plantas, da FCAV/UNESP, foram selecionados quatro, que demonstraram elevada produção de goma 'in vitro'. Este trabalho teve como objetivo investigar o potencial biotecnológico, de isolados de Rhizobium spp. (SEMIA 4064 e JAB6) e dois isolados de Mesorhizobium spp. (LMG 6125 e LMG 11892), como bioemulsificantes e biossorventes. Para a identificação dos isolados foi sequenciada a região 16S rRNA (1500pb). Foram estudados a produção de EPS e aplicação desses biopolímeros como bioemulsificantes de óleos e hidrocarbonetos. Investigando a Reologia e a ... / Abstract: The structures and some compounds produced by microorganisms have a high amount of charges such as, for example, cell wall and biopolymers. The exopolysaccharides (EPSs) of bacteria belonging to the order Rhizobiales have biopolymers that have been widely studied. The EPSs are molecules that have polar groups, this feature they are can to reduce the interfacial tension of water/oil and oil/water. The formation of emulsions is important factor for the biodegradation of oils and hydrocarbons. The charges present in the cell wall on the bacterial cells are predominantly of anionic in nature. These structures are capable of interacting strongly with metal ions and play an important role in sequestering or immobilization of ions in the environment. The application of the populations of rhizobia are interesting biotechnological tools in bioremediation process, these organisms do not present toxicity to health and the environment. Rhizobial isolates belonging to the Laboratory of Biochemistry of Plants and Microorganisms, FCAV / UNESP, four were chosen that demonstrated high gum production in vitro. This work aimed to investigate the potential of biotechnology of the isolates of Rhizobium spp. (SEMIA 4064 and JAB6) and two strains of Mesorhizobium spp. (LMG 6125 and LMG 11892), as biosorbents and bioemulsifiers. For the identification of the isolates were done sequencing of the gene 16S rRNA (1500pb). The production and application of these EPSs were studied as bioemulsifiers of oils and hydrocarbons. Investigating the monosaccharides composition and rheology of the EPSs. These isolates were explored for sensitivity of live cells and the process of removal of dead cells by copper ions (Cu2+) and chromium (Cr6+). The sequencing showed that the isolates LMG 6125 and LMG 11892 were not consistent with the genus and species previously described / Doutor

Conselho Nacional de Desenvolvimento CientÃfico e TecnolÃgico / Com base na necessidade de obter novas formulaÃÃes mais eficientes e diante das propriedades apresentadas pelas molÃculas oriundas de algas marinhas, acredita-se que estas possam ser eficazes no processo de cicatrizaÃÃo. A lectina da alga marinha vermelha Pterocladiella capillacea (PcL) e os polissacarÃdeos da alga vermelha Solieria filiformis (SfP) inicialmente foram analisados em ensaio de toxicidade. PcL foi aplicada no ensaio do edema de pata seguido da dosagem de mieloperoxidase (MPO). Avaliou-se o efeito da lectina da alga Pterocladiella capillacea (PcL) e os polissacarÃdeos das algas Solieria filiformis (SfP) na cicatrizaÃÃo de feridas induzidas em ratos. Ambas as molÃculas foram submetidas a ensaios microbiolÃgicos e analisadas quanto ao efeito no processo de cicatrizaÃÃo em feridas limpas induzidas no dorso de ratos. SfP foi utilizado como um possÃvel veÃculo para a administraÃÃo de PcL e comparado ao Carbopol 940 (C). Os gÃis (0,9%) foram submetidos a anÃlise reolÃgica e entÃo aplicados nas lesÃes durante um perÃodo de tratamento de 10 (dez) dias, utilizando kollagenase como controle. O processo de cicatrizaÃÃo foi avaliado quanto ao tamanho das feridas, dosagem de MPO e anÃlise histolÃgica. PcL e SfP nÃo demonstraram toxicidade quanto aos parÃmetros de peso corpÃreo, ÃrgÃos e dosagens bioquÃmicas. Entretanto a anÃlise histolÃgica mostrou pequenas alteraÃÃes no fÃgado e rim. PcL (1, 3 e 9 mg/kg, i.v.) reduziu o edema induzido por carragenana e quando administrada com seu inibidor mucina nÃo foi possÃvel verificar a reduÃÃo do edema o qual foi confirmado pela dosagem de MPO. As duas molÃculas foram aplicadas em ensaios microbiolÃgicos e nÃo inibiram o crescimento de nenhum micro-organismo testado, os quais tambÃm nÃo foram capazes de utilizar SfP como fonte de carbono. A anÃlise reolÃgica mostrou que os SfP utilizados na formulaÃÃo dos gÃis (PcL+SfP e SfP) apresentaram a caracterÃstica de um pseudoplÃstico. A anÃlise macroscÃpica das feridas mostrou uma reduÃÃo da Ãrea da lesÃo nos animais tratados com PcL+SfP e PcL+C (53,5 e 60%, respectivamente) no sexto dia de administraÃÃo. Na anÃlise histolÃgica, nÃo foi observado infiltrado inflamatÃrio acentuado nos tecidos obtidos atà o 4 dia da administraÃÃo dos gÃis (PcL+SfP e PcL+C) e Kollagenase (controle positivo). No 6 dia, os animais nÃo tratados e os tratados apenas com SfP mostraram infiltrado inflamatÃrio. A dosagem de MPO demonstrou reduÃÃo no processo inflamatÃrio nas amostras contendo PcL, cujo resultado corrobora com a anÃlise histolÃgica. Em conclusÃo, PcL auxiliou no reparo de feridas, sugerindo seu uso futuro como uma possÃvel ferramenta para o tratamento de lesÃes. O papel biolÃgico e farmacolÃgico das lectinas e polissacarÃdeos de algas marinhas faz parte de uma Ãrea de estudos ainda pouco explorada, onde muito conhecimento deverà ser investido visto que estas biomolÃculas podem ser promissoras para a indÃstria farmacÃutica. / Based on the need for new formulations that are more efficient and on the properties provided by molecules derived from seaweed, it is believed that these can be effective in healing process. The lectin from the red seaweed Pterocladiella capillacea (PcL) and the polysaccharides of red algae Solieria filiformis (SfP) were initially analyzed in toxicity testing. PcL was applied to the paw edema test followed by measurement of myeloperoxidase (MPO). We evaluated the effect of the seaweed Pterocladiella capillacea lectin (PcL) and algal polysaccharides Solieria filiformis (SfP) in healing wounds in rats induced. Both molecules were submitted to microbiological tests and assayed for the effect on wound healing in wounds clean induced on the back of rats. SfP was used as a possible vehicle for the administration of PcL and compared to Carbopol 940 (C). The gels (0.9%) were analyzed rheological and then applied to the lesions during a treatment period of 10 days, using kollagenase  as control. The healing process was evaluated on the size of the wounds, levels of MPO and histological analysis. The molecule SfP and PcL is not toxic for the parameters of body weight, organ and biochemical measurements. However, the histological analysis showed minor changes in liver and kidney. PcL (1, 3 and 9 mg / kg, i.v) reduced the edema induced by carrageenan and its inhibitor when administered with mucin was not possible to check the reduction of edema which was confirmed by measurement of MPO. The two molecules were used in microbiological assays and not inhibit growth of any microorganism tested and unable to use SfP as carbon source. The rheological analysis showed that the SfP used in the formulation of the gels (PcL+SfP and SfP) had the characteristic of a pseudoplastic. Macroscopic analysis of wounds showed a reduction in lesion area in the animals treated with PCL, PCL+SfP, PCL+C (53.5 and 60% respectively) on the sixth day of administration. In histological analysis, there was no severe inflammatory infiltrate in the tissues obtained until 4th day of administration of the gels (PcL and PcL+SfP, PcL+C) and Kollagenase (positive control). On day 6, the untreated animals and those treated only with SfP showed inflammatory infiltrate. The measurement of MPO showed a reduction in the inflammatory process in the samples containing PcL, whose results corroborate the histological analysis. In conclusion, PcL aid in wound repair, suggesting its use as a possible future tool for the treatment of lesions. The biological and pharmacological role of lectins and polysaccharides of seaweed is part of a study area little explored, where a lot of knowledge should be invested since these biomolecules can be promising for the pharmaceutical industry.