36 resultados para Biotechnological processes
em Scielo Saúde Pública - SP
Resumo:
Bioflavors and oligosaccharides are two classes of substances that may be produced biotechnologically through microbial bioprocesses. These compounds have attracted the interest of pharmaceutical and food industries not only due to their technological properties (sweetening/fiber or flavoring, respectively), but also as a consequence of other functional properties such as, for example, health promoting benefits. The use of agro-industrial residues as substrates in biotechnological processes seems to be a valuable alternative in helping to overcome the high manufacturing costs of industrial fermentations. This manuscript reviews the most important advances in biotechnological production of bioflavors and oligosaccharides. The use of some agro-industrial residues in such processes is also cited and discussed, showing that this is a rising trend in biotechnology.
Resumo:
Carotenoids are widely distributed in nature, providing yellow, orange or red color in a great number of vegetables, microorganisms and in some animals. Carotenoids act as biological antioxidants and seem to play an important role in human health by protecting cells and tissues from the damaging effects of free radicals and singlet oxygen. Several authors describe the oxidative cleavage of carotenoids in flavor compounds as occuring through chemical or photochemical degradations or through biotechnological processes. Biotransformation of carotenoids seems to be a reasonable alternative to produce flavor compounds since these compounds are considered 'natural' ingredients. In this work we describe the properties of some carotenoids, as well as biotechnological approaches to obtain its oxyfunctionalized derivatives.
Resumo:
Brazil is renowned for its biodiversity; however, its economy is based on exotic plants, extraction and unsustainable use of natural resources. This issue was addressed in a recent QN review entitled "Chemistry without Borders." In order to explore the potential of Brazilian biodiversity fully, sustainable development is required in key technological areas, such as biotechnology. This research field is consistent with the green chemistry and white technology principles. Therefore, biotechnology is a sustainable alternative to conventional technologies and is expected to account for 20% of global chemicals by 2020. Brazil is the second largest grower of biotech crops and biodiesel, but its main activities rely on the fermentative process. In order to stimulate the national biotechnology development, the Brazilian Federal Government launched a national policy for biotechnology in 2007 and the National Committee of Biotechnology was created. Among the outstanding biotechnological processes, biocatalysis is one of the most important alternatives to conventional processing, and this field has changed dramatically with the advent of recombinant DNA technology in the 1970s, when large quantities of enzymes were accessible. The direct evolution methodology in the 1990s was a breakthrough and allowed tailoring of enzymes possessing high stability and stereoselectivity. However, about 60 years after the first industrial enzymatic biotransformation of steroids, the full potential of biocatalysis is far from being achieved. Future challenges in this field concern the multienzyme cascade reactions associated with optimized chemoenzymatic processes, and some recent industrial application of biocatalysts are also highlighted in this perspective.
Resumo:
ABSTRACT2-Phenylethanol (PE) is an aromatic alcohol with a characteristic odor of roses, widely used in food industry to modify certain aroma compositions in formulations with fruit, jam, pudding, and chewing gums, and also in cosmetic and fragrance industry. This compound occurs naturally in low concentrations in some essential oils from flowers and plants. An alternative to plants extraction are biotechnological processes. This study evaluated 2-phenylethanol’s production in cultivation of Saccharomyces cerevisiae in cassava wastewater originated from starch industry. The substrate was supplemented with glucose and L-phenylalanine in order to obtain higher 2-phenylethanol concentrations and better efficiency in glucose/2-phenylethanol conversion. It was performed using Rotatable Center Composite Design and response surface analysis. Cultures were performed under aerobic conditions in a batch system in Erlenmeyer flasks containing 50 mL of medium in shaker at 150 rpm and 24 ± 1 ºC. The highest PE values were obtained with supplementation of 20.0 g.L-1 of glucose and 5.5 g.L-1 of L-phenylalanine, which has been experimentally validated, obtaining a PE production of 1.33 g.L-1 and PE/glucose yield factor of 0.070 g.g-1, equivalent to 74.3 and 89.7% of desirability values according to the validated model.
Resumo:
In biotechnological processes, the culture media components are responsible for high costs and exert a strong influence on the cyanobacteria behavior. The objective of this study was to evaluate the Arthrospira platensis growth potential for biomass production under different cultivation conditions using an experimental design. Three factors that are important for cyanobacteria growth were evaluated: sodium bicarbonate (9 to 18 g/l), sodium nitrate (1.25 to 2.5 g/l), and irradiance (20 to 120 µmol photons/m2.s–1). The results showed that the concentration of NaNO3 in the A. platensis medium can be reduced, resulting in increased concentrations of biomass produced. There was a higher biomass production due to the increase in the concentration of NaHCO3 and irradiance, mainly when these two factors varied tending towards the highest values studied. The results demonstrate the potential to produce Arthrospira platensis with lower costs and effluent generation without affecting cultivation performance.
Resumo:
The different methods of sewage sludge stabilization modify their physical chemical and biological properties, altering its efficiency when applied in agriculture. The objective of this study was to evaluate the nutrient levels in soil and the yield of sunflower fertilized with sewage sludge stabilized by different processes. The experiment was conducted in Cambisol, with the treatments: control (without fertilization), fertilization with sewage sludge solarized, composted, vermicomposted, limed and chemical fertilizer recommended for sunflower crop. The experimental design a randomized block with four replications. The different methods of sewage sludge treatment did not affect the yield; however, the application of sewage sludge, regardless the stabilization process adopted, was more effective than chemical fertilizer and the control treatment. Overall, fertilization with limed sewage sludge provided higher soil nutrients concentrations, while treatments with composted and vermicomposted sewage sludge showed higher levels of nutrients in the plant.
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The role of middle management is essential when managing integrative and emergent strategy formation processes. We stand out the importance of its role connecting micro and macro organizational level offering a very important contribution when examining the strategy-as-practice perspective and integrative strategy formation process. The main goal of this research is to analyse the relationship between the integrative strategy formation process and the roles of middle management under the strategy-as-practice perspective. To check it out we adopted a qualitative methodology droving a case analysis in a Spanish University. Data was collected by means of personal interviews with members of different levels of the Institution, documents analysis and direct observation. In advance of some results we find out that the University develops an integrative strategy formation process and confers to middle management an important role extended all over the organization.
Resumo:
The lysotypes, plasmidial profiles, and profiles of resistance to antimicrobial agents were determined in 111 Salmonella Typhimurium strains isolated from feces and blood of children treated in Rio de Janeiro and in Salvador. Six distinct lysotypes (19, 41, 97, 105, 120 and 193) were recognized, with a predominance of lysotype 193 (59.7%) in Rio de Janeiro and of phage type 105 (38.4) in Salvador. Approximately 86.7% of the lysotype 193 strains presented multiple resistance to more than six antimicrobial agents, whereas 93% of lysotype 105 strains were fully susceptible. More than 90% of the strains presented plasmids distributed into 36 different profiles in Rio de Janeiro and into 10 profiles in Salvador. A 40 MDa plasmid was the most frequent (47%) in the strains from Rio de Janeiro, whereas a 61 MDa plasmid predominated (14.5%) in Salvador. Combined analysis of plasmid profile and classification into lysotypes (especially those belonging to types 105 and 103, proved to be more discriminatory than the other methods applied).
Resumo:
Objective To investigate the relation between gait parameters and cognitive impairments in subjects with Parkinson’s disease (PD) and Alzheimer’s disease (AD) during the performance of dual tasks. Methods This was a cross-sectional study involving 126 subjects divided into three groups: Parkinson group (n = 43), Alzheimer group (n = 38), and control group (n = 45). The subjects were evaluated using the Timed Up and Go test administered with motor and cognitive distracters. Gait analyses consisted of cadence and speed measurements, with cognitive functions being assessed by the Brief Cognitive Screening Battery and the Clock Drawing Test. Statistical procedures included mixed-design analyses of variance to observe the gait patterns between groups and tasks and the linear regression model to investigate the influence of cognitive functions in this process. A 5% significant level was adopted. Results Regarding the subjects’ speed, the data show a significant difference between group vs task interaction (p = 0.009), with worse performance of subjects with PD in motor dual task and of subjects with AD in cognitive dual task. With respect to cadence, no statistical differences was seen between group vs task interaction (p = 0.105), showing low interference of the clinical conditions on such parameter. The linear regression model showed that up to 45.79%, of the variance in gait can be explained by the interference of cognitive processes. Conclusion Dual task activities affect gait pattern in subjects with PD and AD. Differences between groups reflect peculiarities of each disease and show a direct interference of cognitive processes on complex tasks.
Current millennium biotechniques for biomedical research on parasites and host-parasite interactions
Resumo:
The development of biotechnology in the last three decades has generated the feeling that the newest scientific achievements will deliver high standard quality of life through abundance of food and means for successfully combating diseases. Where the new biotechnologies give access to genetic information, there is a common belief that physiological and pathological processes result from subtle modifications of gene expression. Trustfully, modern genetics has produced genetic maps, physical maps and complete nucleotide sequences from 141 viruses, 51 organelles, two eubacteria, one archeon and one eukaryote (Saccharomices cerevisiae). In addition, during the Centennial Commemoration of the Oswaldo Cruz Institute the nearly complete human genome map was proudly announced, whereas the latest Brazilian key stone contribution to science was the publication of the Shillela fastidiosa genomic sequence highlythed on a Nature cover issue. There exists a belief among the populace that further scientific accomplishments will rapidly lead to new drugs and methodological approaches to cure genetic diseases and other incurable ailments. Yet, much evidence has been accumulated, showing that a large information gap exists between the knowledge of genome sequence and our knowledge of genome function. Now that many genome maps are available, people wish to know what are we going to do with them. Certainly, all these scientific accomplishments will shed light on many more secrets of life. Nevertheless, parsimony in the weekly announcements of promising scientific achievements is necessary. We also need many more creative experimental biologists to discover new, as yet un-envisaged biotechnological approaches, and the basic resource needed for carrying out mile stone research necessary for leading us to that "promised land"often proclaimed by the mass media.
Resumo:
Nitric oxide (NO) plays an important role in mediating many aspects of inflammatory responses. NO is an effector molecule of cellular injury, and can act as an anti-oxidant. It can modulate the release of various inflammatory mediators from a wide range of cells participating in inflammatory responses (e.g., leukocytes, macrophages, mast cells, endothelial cells, and platelets). It can modulate blood flow, adhesion of leukocytes to the vascular endothelium and the activity of numerous enzymes, all of which can have an impact on inflammatory responses. In recent years, NO-releasing drugs have been developed, usually as derivatives of other drugs, which exhibit very powerful anti-inflammatory effects.
Resumo:
The cropping system influences the interception of water by plants, water storage in depressions on the soil surface, water infiltration into the soil and runoff. The aim of this study was to quantify some hydrological processes under no tillage cropping systems at the edge of a slope, in 2009 and 2010, in a Humic Dystrudept soil, with the following treatments: corn, soybeans, and common beans alone; and intercropped corn and common bean. Treatments consisted of four simulated rainfall tests at different times, with a planned intensity of 64 mm h-1 and 90 min duration. The first test was applied 18 days after sowing, and the others at 39, 75 and 120 days after the first test. Different times of the simulated rainfall and stages of the crop cycle affected soil water content prior to the rain, and the time runoff began and its peak flow and, thus, the surface hydrological processes. The depth of the runoff and the depth of the water intercepted by the crop + soil infiltration + soil surface storage were affected by the crop systems and the rainfall applied at different times. The corn crop was the most effective treatment for controlling runoff, with a water loss ratio of 0.38, equivalent to 75 % of the water loss ratio exhibited by common bean (0.51), the least effective treatment in relation to the others. Total water loss by runoff decreased linearly with an increase in the time that runoff began, regardless of the treatment; however, soil water content on the gravimetric basis increased linearly from the beginning to the end of the rainfall.
Resumo:
The objective of this work was to evaluate the processes of selection in a citrus hybrid population using segregation analysis of RAPD markers. The segregation of 123 RAPD markers between 'Cravo' mandarin (Citrus reticulata Blanco) and 'Pêra' sweet orange (C. sinensis (L.) Osbeck) was analysed in a F1 progeny of 94 hybrids. Genetic composition, diversity, heterozygosity, differences in chromosomal structure and the presence of deleterious recessive genes are discussed based on the segregation ratios obtained. A high percentage of markers had a skeweness of the 1:1 expected segregation ratio in the F1 population. Many markers showed a 3:1 segregation ratio in both varieties and 1:3 in 'Pêra' sweet orange, probably due to directional selection processes. The distribution analysis of the frequencies of the segregant markers in a hybrid population is a simple method which allows a better understanding of the genetics of citrus group.
Resumo:
After an introductory discussion emphasising the importance of electrochemistry for the so-called Green Chemical Processes, the article presents a short discussion of the classical ozone generation technologies. Next a revision of the electrochemical ozone production technology focusing on such aspects as: fundamentals, latest advances, advantages and limitations of this technology is presented. Recent results about fundamentals of electrochemical ozone production obtained in our laboratory, using different electrode materials (e.g. boron doped diamond electrodes, lead dioxide and DSAÒ-based electrodes) also are presented. Different chemical processes of interest to the solution of environmental problems involving ozone are discussed.