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Obtenção de concentrado protéico de folhas e parte aérea da mandioca (Manihot Esculenta Crantz) / Obtention of proteic concentrate of leaves and aerial part of the cassava (Manihot Esculenta Crantz).Silva, Janaina Lima da 17 July 2007 (has links)
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Previous issue date: 2007-07-17 / Leaves and aerial part of the
cassava are great protein, vitamins, minerals and essential amino acids
sources, being these abundant and in low cost. However, this residual is still
little explored. The cassava leaves use as protein source is, many times, not
stimulated by the presence of anti nutritional factors what indicates the
obtainment of proteic concentrates. The objective of this study was to obtain
proteic concentrates from cassava leaf and aerial part (leaf, stalk and stem)
through 4 extraction methods, besides to evaluate the mineral composition and
functional properties of the obtained concentrates. The extraction methods used
were: 1) Extraction method by isoeletric precipitation described by CEREDA;
VILPOUX (2003); 2) Extraction Method by fermentation described by CHAVES
(1987); 3) Extraction Method by fermentation described by CHAVES (1987) with
fermentation time shortening described by FERRI (2006); 4) Extraction Method
by fermentation described by CHAVES (1987) with pH alteration in the end of
fermentation described by FERRI (2006).It was determined for each method the
extraction yield, the proteic concentrate yield, the mass and protein loss. In the
obtained concentrates were determined the Fe, Mn, Cu, Na, K and Zn levels,
besides the functional properties of water and oil absorption. The factorial 2X4
experimental outline was used, being its factors the material kind (leaf and
aerial part) and the protein extraction methods, with 3 repetitions, constituting
24 experimental parts. The variable analysis was also made, being its averages
compared by the Tukey test in the 5% significance level. The yields obtained on
the leaves were 18,31%, 14,11%,14,40% and 13,45% for methods 1, 2, 3 and 4
respectively. On the aerial parts the yields of concentrate obtained were 3,66%,
6,10%, 6,30% and 6,55% for methods 1, 2, 3 and 4 respectively. The leaves
presented average extraction yield values three to four times bigger than the
values presented by the aerial part, being them more adequate to get proteic
concentrate from. The proteic concentrates obtained presented good quantity of
nutrients like Fe, Mn, Cu, Na, K and Zn, indicating their application in the food
industry, without difference between the concentrates obtained from the leaves
or the aerial part. It was observed an elevated capacity of water absorption on
the proteic concentrates, indicating its application in foods as meat, bread,
soups and sauces. The oil absorption capacity on proteic concentrates was also
high, indicating their industrial application in products preparation as sausages,
dough, mayonnaise and other salad dressings increasing the good flavor
retention of these products. / As folhas e parte aérea da mandioca constituem-se como fontes de proteínas,
vitaminas, minerais e aminoácidos essenciais, abundantes e de baixo custo.
Contudo este resíduo é ainda pouco explorado. O uso de folhas de mandioca
como fonte de proteínas, muitas vezes é desestimulado pela presença de
fatores antinutricionais, indicando a obtenção de concentrados protéicos. O
objetivo do presente trabalho foi obter concentrados protéicos de folha e parte
aérea (folha, haste e caule) de mandioca, por 4 métodos de extração e avaliar
a composição mineral e propriedades funcionais dos concentrados obtidos. Os
métodos de extração utilizados foram: 1) Método de extração por precipitação
isoelétrica descrito por CEREDA; VILPOUX (2003); 2) Método de extração por
fermentação descrito por CHAVES (1987); 3) Método de extração por
fermentação descrito por CHAVES (1987), com redução no tempo de
fermentação descrito por FERRI (2006); 4) Método de extração por
fermentação descrito por CHAVES (1987), com alteração de pH no final da
fermentação proposto por FERRI (2006). Determinou-se para cada método o
rendimento de extração, o rendimento de concentrado protéico, a perda de
massa e perda de proteínas. Nos concentrados obtidos determinou-se o teor
de Fe, Mn, Cu, Na, K e Zn e as propriedades funcionais de absorção de água e
óleo. Utilizou-se delineamento experimental do tipo fatorial 2 x 4, sendo os
fatores, tipo de material (folha e parte aérea) e métodos de extração de
proteínas, com 3 repetições, constituindo 24 parcelas experimentais.
Realizou-se análise de variância, sendo as médias comparadas pelo teste de
Tukey, ao nível de 5% de significância. Para as folhas os rendimentos de
concentrado obtidos foram 18,31%, 14,11%,14,40% e 13,45% para os métodos
1, 2, 3 e 4, respectivamente. Para a parte aérea os rendimentos de
concentrado obtidos foram 3,66%, 6,10%, 6,30% e 6,55% para os métodos 1,
2, 3 e 4, respectivamente. As folhas apresentaram valores médios de
rendimento de extração três a quatro vezes maiores que os valores
apresentados pela parte aérea, indicando serem mais adequadas para
obtenção de concentrado protéico. Os concentrados protéicos obtidos
apresentaram bons conteúdos de nutrientes como Fe, Mn, Cu, Na, K e Zn,
indicando boa aplicação como suplemento na indústria de alimentos, não
havendo diferenças entre os concentrados obtidos de folha ou de parte aérea.
Foi observada elevada capacidade de absorção de água nos concentrados
protéicos, indicando aplicação em alimentos como carnes, pães, sopas e
molhos. A capacidade de absorção de óleo dos concentrados protéicos
também foi elevada, indicando boa aplicação industrial para preparação de
produtos como salsichas, massas de bolos, maionese e outros molhos para
saladas, aumentando a retenção de sabor nestes produtos.
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Optimisation of proteomics techniques for archival tumour blocks of a South African cohort of colorectal cancerRossouw, Sophia Catherine January 2020 (has links)
Philosophiae Doctor - PhD / Tumour-specific protein markers are usually present at elevated concentrations in patient biopsy tissue; therefore tumour tissue is an ideal biological material for studying cancer proteomics and biomarker discovery studies. To understand and elucidate cancer pathogenesis and its mechanisms at the molecular level, the collection and characterisation of a large number of individual patient tissue cohorts are required. Since most pathology institutes routinely preserve biopsy tissues by standardised methods of formalin fixation and paraffin embedment, these archived, FFPE tissues are important collections of pathology material, often accompanied by important metadata, such as patient medical history and treatments. FFPE tissue blocks are conveniently stored under ambient conditions for decades, while retaining cellular morphology due to the modifications induced by formalin. / 2022
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Optimization of protein extraction from red algaeKasparaviciute, Deimante January 2024 (has links)
The plastid is an important organelle that allows eukaryotes to photosynthesize. The endosymbiotic event that led to the development of a primary plastid occurred more than one billion years ago. Since then the organelle has undergone a significant genome reduction, losing a large portion of non-essential genes whose function is covered by the eukaryotic host. The majority of the proteins needed for essential plastid function are transcribed in the nucleus and translated in the cytosol. These proteins are then translocated across the inner and outer plastid membranes. The difference in where proteins are translated and transported can be used to study plastid evolution, this can be done by examining what proteins are present in the red algae plastid and comparing it to proteins found in other algae groups. In this project, the exact placement of the proteins, mainly plastid proteins is of interest. In order to localize and identify proteins in the algal cell, an efficient method of cell lysis, both total and incomplete, where the preservation of organelles is essential needs to be developed. This thesis examines a set of different methods of cell lysis, both complete and incomplete, coupled with organelle fractionation, to achieve the isolation of proteins belonging to the different cellular compartments. I show that complete cell lysis with bead milling using 0.1-0.5 mm silica beads is more efficient than a method using a Dounce homogenizer. For incomplete lysis, I show that nitrogen cavitation at 750 psi for 15 min and 1,000 psi for 30 min provides the same level of cellular lysis, indicating that the nitrogen gas equilibrates within 15 minutes. Organelle fractionation with OptiprepTM gradient showed that the majority of the sample did not travel through the gradient, staying in the first layer, which also prevented revelation of the protein pattern on an SDS-PAGE gel, indicating insufficient centrifugation. A great deal of optimization is still required to make these methods as efficient as possible. The step that requires the most optimization is sample preparation for nitrogen cavitation and the use of an ultracentrifuge.
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MALDI-TOF MS for identification of Aspergillus species : A pilot study preceding possible implementation of MALDI-TOF MS to complement morphological assessmentLindström, Christel January 2020 (has links)
Matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF MS) has revolutionized the field of bacterial diagnostics and is also used for routine analysis in smaller clinical laboratories. For identification of moulds, pre-analytical steps are more complicated and time consuming than for bacteria, and the choice of reference library has a big impact on the utility of MALDI-TOF MS. The aim of this study was to investigate if MALDI-TOF MS is applicable for identification of moulds belonging to the genus Aspergillus at the hospital laboratory in Gävle. Therefore, strains belonging to the genus Aspergillus and Penicillium, were analysed with MALDI-TOF MS after 2, 4 and 7 days of incubation. Two different extraction protocols were used and compared. Mass spectra were compared to reference spectra in two different databases: MSI-2 and RUO Compass library/BDAL (Bruker). Of the strains included, 97 % were correctly identified to species complex level with MSI-2. Only 25 % were identified to species level with RUO Compass library/BDAL (Bruker). However, totally 56 % were correctly identified to species complex level if a lower score value limit than recommended for identification, were applied. Significantly raised score values were observed with one of the protein extraction protocols used. Although, in most cases, the strains were considered identified to species complex level with either method. This pilot study conveys the feasibility of MALDI-TOF MS for identification of Aspergillus species in a clinical laboratory. While there are still issues to address, applying MALDI-TOF MS has the potential to allow for quicker and more precise identification, also in this specific clinical setting.
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Algae Characterization and Processing TechniquesBosley, Amber L. January 2011 (has links)
No description available.
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Coagulant Protein from plant materials: Potential Water Treatment AgentBodlund, Ida January 2013 (has links)
Access to fresh water is a human right, yet more than 780 million people, especially in rural areas, rely on unimproved sources and the need for finding ways of treating water is crucial. Although the use of natural coagulant protein in drinking water treatment has been discussed for a long time, the method is still not in practice, probably due to availability of material and limited knowledge. In this study, about hundred different crude extracts made from plant materials found in Southern India were screened for coagulation activity. Extracts of three Brassica species (Mustard, Cabbage and Cauliflower) were showing activity comparable to that of Moringa oleifera and were further investigated. Their protein content and profile were compared against each other and with coagulant protein from Moringa. Mustard (large) and Moringa seed proteins were also studied for their effect against clinically isolated bacterial strains. The protein profiles of Brassica extract showed predominant bands around 9kDa and 6.5kDa by SDS-PAGE. The peptide sequence analysis of Mustard large identified the 6.5kDa protein as Moringa coagulant protein (MO2.1) and the 9kDa protein band as seed storage protein napin3. Of thirteen clinical strains analysed, Moringa and Mustard large were proven effective in either aggregation activity or growth kinetic method or both in all thirteen and nine strains respectively. To my knowledge this is the first report on the presence of coagulant protein in Brassica seeds. Owing to the promising results Brassica species could possibly be used as a substitute to Moringa coagulating agent and chemicals in drinking water treatment. / <p>QC 20121214</p>
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Soy-Polypropylene Biocomposites for Automotive ApplicationsGuettler, Barbara Elisabeth 15 May 2009 (has links)
For the automotive sector, plastics play the most important role when designing interior and exterior parts for cars. Currently, most parts are made from petroleum-based plastics but alternatives are needed to replace environmentally harmful materials while providing the appropriate mechanical performance and preferably reduce the cost for the final product.
The objective of this work was to explore the use of soy flakes as natural filler in a composite with polypropylene and to investigate the mechanical properties, water absorption and thermal behaviour. For a better understanding of the filler, the soy flakes were characterized extensively with analytical and microscopic methods.
Two types of soy fillers were investigated, soy flakes, provided by Bunge Inc., with a 48 wt-% protein content and an industrial soy based filler with 44 wt-% protein content and provided by Ford.
The size of the soy flakes after milling was mainly between 50 and 200 µm and below 50 µm for the industrial filler. The aspect ratio for all filler was below 5. The soy flakes were used after milling and subjected to two pre-treatment methods: (1) one hour in a 50 °C pH 9 water solution in a 1 : 9 solid-liquid ratio; (2) one hour in a 50 °C pH 9 1M NaCl solution in a 1 : 9 solid-liquid ratio. A control filler, without pre-treatment was considered. The soy flakes were also compared to an industrial soy based filler provided by Ford (soy flour (Ford)). The thermogravimetric analysis showed an onset of degradation at 170 °C for the treated filler (ISH2O and ISNaCl) and 160 °C for the untreated filler.
The biocomposites formulation consisted of 30 wt-% filler, and polypropylene with/without 0.35 wt-% anti-oxidant Irganox 1010 and with/without the addition of MA-PP as coupling agent. All biocomposites were compounded in a mini-extruder, pressed into bars by injection moulding and tested subsequently.
The mechanical properties of the biocomposites are promising. An increase of the E-modulus was observed when compared to pure polypropylene. The addition of MA-PP as coupling agent increased the yield strength of the biocomposites. When pure polypropylene and the biocomposites were compared no difference could be seen for their yield strength.
The thermal behaviour deduced from differential scanning calorimetry, revealed a similar behaviour for the biocomposites and the pure polypropylene. Only the samples treated in the presence of NaCl and without a coupling agent, appear to have a slightly higher degree of crystallinity. The melt flow index was slightly increased for the biocomposites containing soy flakes pre-treated with NaCl and decreased for biocomposites containing the soy flour.
The water absorption behaviour of the biocomposites was quite similar at the beginning with a slightly lower absorption for the materials with coupling agent. After three months, all samples except the ones treated with water showed a weight loss that can be due to the leaching of the water soluble components in the untreated filler and the NaCl treated filler.
In conclusion, soy flakes represent an attractive filler when used in a polypropylene matrix if an aqueous alkaline pre-treatment is performed. The aqueous alkaline extraction also leads to the recovery of the proteins that can be used in food products while the remaining insoluble material is used for the biocomposites, avoiding the competition with the use of soy for food products...
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Soy-Polypropylene Biocomposites for Automotive ApplicationsGuettler, Barbara Elisabeth 15 May 2009 (has links)
For the automotive sector, plastics play the most important role when designing interior and exterior parts for cars. Currently, most parts are made from petroleum-based plastics but alternatives are needed to replace environmentally harmful materials while providing the appropriate mechanical performance and preferably reduce the cost for the final product.
The objective of this work was to explore the use of soy flakes as natural filler in a composite with polypropylene and to investigate the mechanical properties, water absorption and thermal behaviour. For a better understanding of the filler, the soy flakes were characterized extensively with analytical and microscopic methods.
Two types of soy fillers were investigated, soy flakes, provided by Bunge Inc., with a 48 wt-% protein content and an industrial soy based filler with 44 wt-% protein content and provided by Ford.
The size of the soy flakes after milling was mainly between 50 and 200 µm and below 50 µm for the industrial filler. The aspect ratio for all filler was below 5. The soy flakes were used after milling and subjected to two pre-treatment methods: (1) one hour in a 50 °C pH 9 water solution in a 1 : 9 solid-liquid ratio; (2) one hour in a 50 °C pH 9 1M NaCl solution in a 1 : 9 solid-liquid ratio. A control filler, without pre-treatment was considered. The soy flakes were also compared to an industrial soy based filler provided by Ford (soy flour (Ford)). The thermogravimetric analysis showed an onset of degradation at 170 °C for the treated filler (ISH2O and ISNaCl) and 160 °C for the untreated filler.
The biocomposites formulation consisted of 30 wt-% filler, and polypropylene with/without 0.35 wt-% anti-oxidant Irganox 1010 and with/without the addition of MA-PP as coupling agent. All biocomposites were compounded in a mini-extruder, pressed into bars by injection moulding and tested subsequently.
The mechanical properties of the biocomposites are promising. An increase of the E-modulus was observed when compared to pure polypropylene. The addition of MA-PP as coupling agent increased the yield strength of the biocomposites. When pure polypropylene and the biocomposites were compared no difference could be seen for their yield strength.
The thermal behaviour deduced from differential scanning calorimetry, revealed a similar behaviour for the biocomposites and the pure polypropylene. Only the samples treated in the presence of NaCl and without a coupling agent, appear to have a slightly higher degree of crystallinity. The melt flow index was slightly increased for the biocomposites containing soy flakes pre-treated with NaCl and decreased for biocomposites containing the soy flour.
The water absorption behaviour of the biocomposites was quite similar at the beginning with a slightly lower absorption for the materials with coupling agent. After three months, all samples except the ones treated with water showed a weight loss that can be due to the leaching of the water soluble components in the untreated filler and the NaCl treated filler.
In conclusion, soy flakes represent an attractive filler when used in a polypropylene matrix if an aqueous alkaline pre-treatment is performed. The aqueous alkaline extraction also leads to the recovery of the proteins that can be used in food products while the remaining insoluble material is used for the biocomposites, avoiding the competition with the use of soy for food products...
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Imbalance of SMC1 and SMC3 Cohesins Causes Specific and Distinct EffectsLaugsch, Magdalena, Seebach, Jochen, Schnittler, Hans, Jessberger, Rolf 22 January 2014 (has links) (PDF)
SMC1 and SMC3 form a high-affinity heterodimer, which provides an open backbone of the cohesin ring, to be closed by a kleisin protein. RNAi mediated knock-down of either one heterodimer partner, SMC1 or SMC3, is expected to cause very similar if not identical phenotypes. However, we observed highly distinct, protein-specific phenotypes. Upon knock-down of human SMC1, much of SMC3 remains stable, accumulates in the cytoplasm and does not associate with other cohesin proteins. Most of the excess nuclear SMC3 is highly mobile and not or only weakly chromosome-associated. In contrast, human SMC3 knock-down rendered SMC1 instable without cytoplasmic accumulation. As observed by differential protein extraction and in FRAP experiments the remaining SMC1 or SMC3 proteins in the respective SMC1 or SMC3 knock-down experiments constituted a cohesin pool, which is associated with chromatin with highest affinity, likely the least expendable. Expression of bovine EGFP-SMC1 or mouse EGFP-SMC3 in human cells under conditions of human SMC1 or SMC3 knock-down rescued the respective phenotypes, but in untreated cells over-expressed exogenous SMC proteins mis-localized. Paucity of either one of the SMC proteins causes RAD21 degradation. These results argue for great caution in interpreting SMC1 and SMC3 RNAi or over-expression experiments. Under challenged conditions these two proteins unexpectedly behave differently, which may have biological consequences for regulation of cohesin-associated functions and for human cohesin pathologies.
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Imbalance of SMC1 and SMC3 Cohesins Causes Specific and Distinct EffectsLaugsch, Magdalena, Seebach, Jochen, Schnittler, Hans, Jessberger, Rolf 22 January 2014 (has links)
SMC1 and SMC3 form a high-affinity heterodimer, which provides an open backbone of the cohesin ring, to be closed by a kleisin protein. RNAi mediated knock-down of either one heterodimer partner, SMC1 or SMC3, is expected to cause very similar if not identical phenotypes. However, we observed highly distinct, protein-specific phenotypes. Upon knock-down of human SMC1, much of SMC3 remains stable, accumulates in the cytoplasm and does not associate with other cohesin proteins. Most of the excess nuclear SMC3 is highly mobile and not or only weakly chromosome-associated. In contrast, human SMC3 knock-down rendered SMC1 instable without cytoplasmic accumulation. As observed by differential protein extraction and in FRAP experiments the remaining SMC1 or SMC3 proteins in the respective SMC1 or SMC3 knock-down experiments constituted a cohesin pool, which is associated with chromatin with highest affinity, likely the least expendable. Expression of bovine EGFP-SMC1 or mouse EGFP-SMC3 in human cells under conditions of human SMC1 or SMC3 knock-down rescued the respective phenotypes, but in untreated cells over-expressed exogenous SMC proteins mis-localized. Paucity of either one of the SMC proteins causes RAD21 degradation. These results argue for great caution in interpreting SMC1 and SMC3 RNAi or over-expression experiments. Under challenged conditions these two proteins unexpectedly behave differently, which may have biological consequences for regulation of cohesin-associated functions and for human cohesin pathologies.
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