Adilma Regina Pippa Scamparini

Própolis produzida no sul do Brasil, Argentina e Uruguai: evidências fitoquímicas de sua origem vegetal

Propolis is a resinous hive product collected by honeybees from plant source. The composition of the propolis depends upon the time, vegetation and the area of collection. Propolis produced by africanized Apis mellifera from south Brazil, Argentine and Uruguay have been investigated using chromatographic techniques. In accordance with results RP-HPTLC, RP-HPLC, and GC-MS, propolis from south Brazil were classified IN 5 groups. Based on chemical evidence Populus alba was shown to be the main propolis source of group 3 from south Brazil, Argentine and Uruguay.

Selection and characterization of carotenoid-producing yeasts from Campinas region, Brazil

The objective of the present study was to select and identify yeasts from Brazil capable of producing carotenoids. Pigmented yeasts were isolated from soil, leaves, fruits, flowers and a processed product. The samples were incubated at 30oC in Erlenmeyer flasks, containing YM broth. After 48 hours, they were inoculated in Petri dishes with YM agar, and incubated at 30oC during 120 hours. The yeast colonies, which presented yellow to red coloration, were transferred to culture tubes containing YM agar, and incubated at 30oC for 72 hours. Out of 242 samples, only five had yellow to red color at high intensity. These highly pigmented yeasts were re-isolated in Petri dishes with YM agar and then transferred to tubes with GPYM agar. Identification through morphological and reproduction characteristics, along with physiological and biochemical tests, classified four strains as R. mucilaginosa and one strain as R. graminis. The main carotenoids extracted from them were identified through HPLC analysis as b-carotene and torulene. The strains showed potential as promising microorganisms for the commercial production of carotenoids.

Production of insoluble exopolysaccharide of Agrobacterium sp. (ATCC 31749 and IFO 13140).

Agrobacterium isolated from soil samples produced two extracellular polysaccharides: succinoglycan, an acidic soluble polymer, and curdlan gum, a neutral, insoluble polymer. Maize glucose, cassava glucose, and maize maltose were used in fermentation medium to produce insoluble polysaccharide. Two Agrobacterium sp. strains which were used (ATCC 31749 and IFO 13140) in the production of insoluble exopolysaccharide presented equal or superior yields compared to the literature. The strain ATCC 31749 yielded better production when using maize maltose, whose yield was 85%, whereas strain IFO 13140 produced more when fed maize glucose, producing a yield of 50% (on reducing sugars).Agrobacterium isolated from soil samples produced two extracellular polysaccharides: succinoglycan, an acidic soluble polymer, and curdlan gum, a neutral, insoluble polymer. Maize glucose, cassava glucose, and maize maltose were used in fermentation medium to produce insoluble polysaccharide. Two Agrobacterium sp. strains which were used (ATCC 31749 and IFO 13140) in the production of insoluble exopolysaccharide presented equal or superior yields compared to the literature. The strain ATCC 31749 yielded better production when using maize maltose, whose yield was 85%, whereas strain IFO 13140 produced more when fed maize glucose, producing a yield of 50% (on reducing sugars).

Conversão de malonil-beta-glicosil isoflavonas em isoflavonas glicosadas presentes em alguns cultivares de soja brasileira

Sendo o Brasil um grande produtor mundial de soja, torna-se necessario uma avaliacao do teor de isoflavonas naqueles cultivares de maior importância para o setor agricola e a verificacao do efeito da temperatura na composicao destas isoflavonas na soja. Neste trabalho pode-se observar que na temperatura de 25oC, o cultivar IAC Foscarin 31-1 apresentou teor medio de isoflavonas de 1405mg/g, enquanto que o cultivar IAC 15-1 apresentou cerca de 3008mg/g. O aquecimento a 121oC durante 40 minutos promoveu uma reducao de ate 17,6 vezes no teor de malonil isoflavonas e um aumento de aproximadamente 2,6 vezes na concentracao de glicosil isoflavonas.

Structural studies of CV-70 polysaccharide

The goal of this paper is the characterization of the chemical structure of the water-soluble polysaccharide, CV-70, produced by bacteria Beijerinckia sp. Beijerinckia sp. is a genus of gram-negative, aerobic bacteria, usually found in sugar cane root. The CV-70 polysaccharide was produced in a fermentation medium containing 5% sucrose as the carbon source, tryptose and salts, at 25 degrees C [1]. The polysaccharide was hydrolyzed with 2 N trifluoroacetic acid at 100 degrees C for 16 h, purified, and analyzed by HPLC. Index of refraction was used for the detection of sugars. For GC-MS analysis, the CV-70 polysaccharide was derivatized through methylation and acetylation. Together with the GC-MS data, periodate oxidation studies were used to determine the possible glucosidic linkages. Carbon-13 NMR studies were carried out with hydrolyzed and silylated samples. Glucose, galactose and fucose were identified as the components in the CV-70 polysaccharide, in a 3:1:3 ratio.

Survival of Beijerinckia sp. microencapsulated in carbohydrates by spray-drying.

The encapsulation of Beijerinckia sp. cell suspension in different wall materials using the spray drying technique was performed. Mat dextrin, dehydrated glucose syrups, gum acacia and modified starch materials were tested. Cell viability assays were carried out before and after drying and during storage of the products. The surface area and characteristics of the encapsulated powders were examined using BET adsorption of N2 and scanning electron microscopy, respectively. The residual moisture content and water activity of the powders were also determined. The best results were obtained with the dehydrated glucose syrup, which resulted in products with the greatest per cent survival during the drying process and subsequent storage period. The products obtained with the dehydrated glucose syrup showed more uniform microcapsule surfaces at lower Aw values and residual moisture content.

Isoflavonas em isolados e concentrados protéicos de soja

Soy protein isolate (SPI) and soy protein concentrate (SPC) are largely used in bakery, confectionary, meat and beverage products. Isoflavones present in soybeans products can undergo changes in quantity and profile depending on the processing conditions. The objective of this work was to conduct mass balance studies of isoflavones and protein during the processing of SPI and SPC (acid and alcohol leach). The majority of isoflavones present in the raw material is lost in the supernatants (90% for SPC treated with alcohol, 52% for SPI and 47% for SPC treated with acid). Total concentration of isoflavones was 652µg/g for SPI, 838µg/g for SPC (acid leach), and only 147µg/g for SPC (alcohol leach). There were no changes in the profile of isoflavones in this last process, whereas in the previous two, the amount of malonyl glycosides decreased while the total amount of b-glycosides and aglucones significantly increased.

Produção de biopolímero sintetizado por Sphingomonas capsulata a partir de meios industriais

Com este trabalho, avaliou-se a producao de biopolimero sintetizado por Sphingomonas capsulata ATCC 14666, utilizando-se os meios industriais melaco bruto e pre-tratado e residuo de proteina texturizada de soja (PTS). Foram testadas diferentes concentracoes de meios industriais (2,66, 4, 6 e 8%), cujas condicoes de fermentacao utilizadas foram 28o ± 2oC, 208 rpm, 72 h. Os ensaios foram realizados em triplicata e os resultados foram avaliados estatisticamente mediante o teste de Tukey. As melhores produtividades foram obtidas para melaco pre-tratado 8% (0,290 gL-1h-1), seguida de extrato aquoso de residuo de PTS 6% (0,240 gL-1h-1) e melaco bruto 8% (0,190 gL-1h-1). A qualidade reologica das gomas foi demonstrada atraves da leitura de viscosidade aparente de solucoes aquosas e salinas a 25 e 60oC.

Exopolysaccharide production by encapsulated Beijerinckia cultures

Abstract It is desirable that spray-dried microorganisms maintain their viability and activity during encapsulation, a possibility that depends on the strain and the conditions of encapsulation. A wide variety of modifications may occur in cells after encapsulation. This work examines the effects of encapsulation in malt dextrin on the production of biopolymer, comparing encapsulated and non-encapsulated Beijerinckia cells. From the characterisation of the biopolymers and study of the fermentation kinetics, it was shown that the encapsulation of Beijerinckia mainly influenced cell growth and biopolymer production.

Structure of xanthan gum and cell ultrastructure at different times of alkali stress

The effect of alkali stress on the yield, viscosity, gum structure, and cell ultrastructure of xanthan gum was evaluated at the end of fermentation process of xanthan production by Xanthomonas campestris pv. manihotis 280-95. Although greater xanthan production was observed after a 24 h-alkali stress process, a lower viscosity was observed when compared to the alkali stress-free gum, regardless of the alkali stress time. However, this outcome is not conclusive as further studies on gum purification are required to remove excess sodium, verify the efficiency loss and the consequent increase in the polymer viscosity. Alkali stress altered the structure of xanthan gum from a polygon-like shape to a star-like form. At the end of the fermentation, early structural changes in the bacterium were observed. After alkali stress, marked structural differences were observed in the cells. A more vacuolated cytoplasm and discontinuities in the membrane cells evidenced the cell lysis. Xanthan was observed in the form of concentric circles instead of agglomerates as observed prior to the alkali stress.