Parâmetros genéticos para caracteres de crescimento, de produção e tecnológicos da madeira em clones de Eucalyptus spp

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

Influência do número kappa, dos ácidos hexenurônicos e da lignina no desempenho da deslignificação com oxigênio

This study aimed at determining the effect of kappa number, lignin and hexenuronic acid contents on oxygen stage performance. Industrial brown pulps produced by the ITC and KobudoMARI cooking technologies, of kappa number and HexA's contents varying in the range of 10-21.7 and 23.2-56.7 mmol/kg, respectively, were collected in a period of 6 months and delignified with oxygen under fixed conditions. Kappa number was fractionated into lignin and hexenuronic acid and each fraction correlated with oxygen stage performance. It was concluded that O-stage efficiency, selectivity and yield does not correlate significantly with kappa number, lignin or hexenuronic acid contents for the ITC and KobudoMARI pulps at 5% of significance.

Desenvolvimentos da biopolpação no Brasil

Biopulping is a technology which application can be advantageous to mechanical or chemical pulping. It presents benefits such as the creation of stronger pulp, as well as energy or chemicals savings. This paper gives an overview of the recent efforts to develop biopulping processes in Brazil as well as provides critical information on biopulping development worldwide. Eucalyptus grandis wood chips have been biotreated by Ceriporiopsis subvermispora in a 50-ton biopulping pilot-plant and used to produce TMP and CTMP pulps on a mill scale, Up to 18% and 27% energy savings have been observed for producing 450-470 CSFreeness TMP and CTMP pulps. Despite darker bio-TMP pulps are produced, one-stage bleaching with 5% H2O2 was sufficient to improve brightness values to 70% and 72% for bio-TMP and control pulps, respectively. Understanding biopulping mechanisms is also relevant because more resistant and competitive fungal species could be selected with basis on a function-directed screen-ing project. As far as the chemical changes induced by the fungus in wood are concerned, recent efforts have pointed out for two different types of wood transformations. One of them involves intense lignin depolymerization in short biotreatment periods, while the other indicates that esterification reactions of oxalate secreted by the Jungas on the polysaccharides chains increase the water saturation point of the fibers. Both transformations are expected to affect the fiber-fiber bonding and, consequently, the physical resistance of wood.

Effects of hemostatic agents on the histomorphologic response of human dental pulp capped with calcium hydroxide

Objective: To evaluate the response of human pulps capped with a calcium hydroxide [Ca(OH)2] cement after bleeding control with 2 hemostatic agents. Method and Materials: Pulps were exposed on the occlusal floor, and the bleeding was controlled either with saline solution (SS) or 2.5% sodium hypochlorite (NaOCI) (SH). After that, the pulp was capped with Ca(OH) 2 cement and restored with resin composite. After 30 (groups SS30 and SH30) and 60 (groups SS60 and SH60) days, the teeth were extracted and processed with hematoxylin-eosin and categorized in a histologic score system. The data were subjected to Kruskal-Wallis and Mann-Whitney tests (α = .05). Results: Regarding dentin bridge formation, an inferior response of SH60 group was observed when compared to SS60 (P < .05). The response of the SH30 group generally was similar to that of the groups treated with saline solution. However, after 60 days, 2.5% NaOCl showed a trend toward having an inferior response. Conclusion: Using saline solution as a hemostatic agent before pulp capping with Ca(OH)2 resulted in a significantly better histomorphologic response than using 2.5% NaOCl as a hemostatic agent before capping with Ca(OH)2.

Evaluation of two mineral trioxide aggregate compounds as pulp-capping agents in human teeth

Aim: The present randomized, controlled prospective study evaluated the histomorphological response of human dental pulps capped with two grey mineral trioxide aggregate (MTA) compounds. Methodology: Pulp exposures were performed on the occlusal floor of 40 human permanent pre-molars. The pulp was capped either with ProRoot (Dentsply) or MTA-Angelus (Angelus) and restored with zinc oxide eugenol cement. After 30 and 60 days, teeth were extracted and processed for histological examination and the effects on the pulp were scored. The data were subjected to Kruskal-Wallis and Conover tests (α = 0.05). Results: In five out of the 40 teeth bacteria were present in pulp tissue. No significant difference was observed between the two materials (P > 0.05) in terms of overall histological features (hard tissue bridge, inflammatory response, giant cells and particles of capping materials). Overall, 94% and 88% of the specimens capped with MTA-Angelus and ProRoot, respectively, showed either total or partial hard tissue bridge formation (P > 0.05). Conclusions: Both commercial materials ProRoot (Dentsply) and MTA-Angelus (Angelus) produced similar responses in the pulp when used for pulp capping in intact, caries-free teeth. © 2009 International Endodontic Journal.

Proximate composition of guariroba (Syagrus oleracea), jerivá (Syagrus romanzoffiana) and macaúba (Acrocomia aculeata) palm fruits

This study aimed to characterize the pulp and kernel of guariroba (Syagrus oleracea), jerivá (Syagrus romanzoffiana) and macaúba (Acrocomia aculeata) palm fruits, through their proximate composition, carotenoids contents and tocopherol composition. The three kernels showed to be composed mainly of lipids and proteins, as the three pulps, of carbohydrate and fiber. In the kernels the levels of lipids ranged from 45.17 to 56.37% and proteins from 15.46 to 28.61%. In the pulps the total fiber content ranged from 20.26 to 26.98%. The pulps also presented a significant amount of ash, which represents a significant mineral content, especially in the guariroba (5.16%). Moreover, the pulp oils showed higher carotenoids and tocopherol contents. The jerivá pulp oil contained carotenoid and tocopherol on average 1219 μg/g and 323.50. mg/kg, respectively. The consumption of the whole fruit, pulp, and kernel supplies important quantities of many necessary nutrients for human diet, including vitamins A and E. © 2011 Elsevier Ltd.

Shelf Life of Fresh and Pasteurized Organic Passion Fruit (Passiflora Edulis F. Flavicarpa Deg.) Pulp

The shelf life of the organic passion fruit pulp, both fresh and pasteurized at 70C and 90C and stored under refrigeration, was evaluated. The heat treatment did not affect the sensory and physicochemical characteristics of the pasteurized pulps when compared with the fresh pulp, except for the ascorbic acid content. The pulps were also microbiologically safe. The pulps pasteurized at 70 and 90C were suitable for consumption for a minimum shelf-life period of 207 days of storage under refrigeration and for the fresh pulp it was attributed a shelf-life period of 60 to 90 days. The pulp pasteurized at 70C showed higher acceptance scores for all the attributes and purchase intention scores, suggesting a more stable behavior and higher sensory quality. Practical Applications: This work intended to evaluate the influence of the minimum pasteurization on the sensory acceptance and microbiological and physicochemical characteristics of the organic passion fruit pulp stored under refrigeration, with the aim to identify the shelf life. Heat treatment is one of the processes used for food preservation. Lower pasteurization temperature than that used by the Brazilian industries and storage under refrigeration showed to be appropriate for passion fruit pulp quality. In this way, the microbiological, physicochemical and sensory features of passion fruit were preserved. This work can be used as a reference for passion fruit pasteurization, which is able to increase the shelf life of this fruit while preserving its desirable original features. Journal Compilation © 2012 Wiley Periodicals, Inc.

Persistence of epoxy-based sealer residues in dentin treated with different chemical removal protocols

The presence of residual endodontic sealer in the pulp chamber may cause discoloration of the dental crown and interfere with the adhesion of restorative materials. The aim of this study was to compare the efficacy of different solvents in removing residues of an epoxy resin-based sealer (AH Plus) from the dentin walls of the pulp chamber, by scanning electron microscopy (SEM). Forty-four bovine incisor dental crown fragments were treated with 17% EDTA and 2.5% NaOCl. Specimens received a coating of AH Plus and were left undisturbed for 5 min. Then, specimens were divided in four groups (n = 10) and cleaned with one of the following solutions: isopropyl alcohol, 95% ethanol, acetone solution, or amyl acetate solution. Negative controls (n = 2) did not receive AH Plus, while in positive controls (n = 2) the sealer was not removed. AH Plus removal was evaluated by SEM, and a score system was applied. Data were analyzed by Kruskal-Wallis and Dunn tests. None of the solutions tested was able to completely remove AH Plus from the dentin of the pulp chamber. Amyl acetate performed better than 95% ethanol and isopropyl alcohol (p < 0.05), but not better than acetone (p > 0.05) in removing the sealer from dentin. No significant differences were observed between acetone, 95% ethanol, and isopropyl alcohol (p > 0.05). It was concluded that amyl acetate and acetone may be good options for cleaning the pulp chamber after obturation with AH Plus. SCANNING 35:17-21, 2013. © 2012 Wiley Periodicals, Inc. © Wiley Periodicals, Inc.

Xylanase and β-Xylosidase from Penicillium janczewskii: Production, Physico-Chemical properties, and application of the crude extract to pulp biobleaching

Extracellular xylanase and β-xylosidase production by a Penicillium janczewskii strain were investigated in liquid cultures with xylan from oat spelts under different physical and chemical conditions. The selected conditions for optimized production of xylanase and β-xylosidase were 7 days, pH 6.5, at 30 °C and 8 days, pH 5.0, at 25 °C, respectively. The xylanase exhibited optimal activity in pH 5.0 at 50 °C and the β- xylosidase in pH 4.0 at 75 °C. The xylanase was more stable at pH 6.0 to 9.5, while the β-xylosidase remained stable at pH ranging from 1.6 to 5.5. The xylanase half-life (T50) at 40, 50, and 60 °C was 183, 15, and 3 min, respectively. β-xylosidase half-life was 144, 8, and 4 min at 50, 65, and 75 °C, respectively. When applied to the biobleaching of Eucalyptus kraft pulp, xylanase dosages of 2 and 4 U/g dried pulp reduced, respectively, kappa number by 3.0 and 3.3 units after 1 h treatment, demonstrating that the use of P. janczewskii xylanases in this process is quite promising. The pulp viscosity was not altered, confirming the absence of cellulolytic enzymes in the fungal extract.

Kraft pulp from juvenile and mature woods of corymbia citriodora

Kraft pulp produced from juvenile and mature wood from thirty-two-year-old Corymbia citriodora trees was evaluated. The stem was subdivided into regions of juvenile and mature wood, and then it was transformed into chips. These materials were then cooked in the Laboratory of Pulp and Paper at São Paulo State University (UNESP, Botucatu, SP, Brazil) and the physico-mechanical properties of the pulps were determined. The results showed that: (1) the pulp yields of mature wood were up to 4.4% greater in comparison to the juvenile wood, (2) the juvenile wood pulp required a shorter refining time than mature wood to reach the same Schopper-Riegler degree, (3) the juvenile wood pulp presented lower specific volume, and (4) the mature wood pulp presented greater air resistance, tensile, tear and burst index values, stress-strain factor, and stretch than the juvenile wood pulp.

Resposta pulpar de dentes de ratos após tratamento capeador direto com sistema adesivo monocomponente ou autocondicionante

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

Contribuição ao estudo bioquímico de frutas tropicais e exóticas produzidas no Brasil: pectina, açúcar e proteína

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

Caracterização química, microbiológica e farmacognóstica da polpa de coquinho-azedo (Butia capitata (Mart) Becc) produzida em Arinos-MG

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

Qualidade microbiológica e ocorrência de leveduras em bebidas lácteas fermentadas, com adição de polpas de frutas, comercializada na região de São José do Rio Preto - SP

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

Qualidade microbiológica e ocorrência de leveduras em polpas congeladas de frutas

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)