9 resultados para Agro-industrial substrate
em Biblioteca Digital da Produção Intelectual da Universidade de São Paulo
Resumo:
Current studies about lipase production involve the use of agro-industrial residues and newly isolated microorganisms aimed at increasing economic attractiveness of the process. Based on these aspects, the main objective of this work is to perform the partial characterization of enzymatic extracts produced by a newly isolated Penicillium crustosum in solid-state fermentation. Lipase extract presented optimal temperature and pH of 37 A degrees C and 9-10, respectively. The concentrated enzymatic extract showed more stability at 25 A degrees C and pH 7. The enzymes kept 100% of their enzymatic activity until 60 days of storage at 4 and -10 A degrees C. The stability under calcium salts indicated that the hydrolytic activity presented decay with the increase of calcium concentration. The specificity under several substrates indicated good enzyme activities in triglycerides from C4 to C18.
Resumo:
Pleurotus ostreatus fungus forms an edible mushroom that possesses important nutritional and medicinal properties. Selenium (Se) is essential to human diets and it is in low concentration in the soil, and consequently in food. P. ostreatus was grown in coffee husks enriched with various concentrations of sodium selenite. The biological efficiency of P. ostreatus was affected by the addition of high concentrations of Se. The highest level of Se absorption was obtained by adding 51 mg kg(1) of sodium selenite. The mushrooms from first flush contained more Se than the further flushes. These results demonstrate the great potential of coffee husks in the production of Se-enriched mushrooms and show the ability of this fungus to absorb and biomagnify Se. (C) 2011 Elsevier Ltd. All rights reserved.
Resumo:
Significant amounts of wastes are generated by the coffee industry, among of which, coffee silverskin (CS) and spent coffee grounds (SCG) are the most abundantly generated during the beans roasting and instant coffee preparation, respectively. This study evaluated the sugars metabolism and production of ethanol by three different yeast strains (Saccharomyces cerevisiae, Pichia stipitis and Kluyveromyces fragilis) when cultivated in sugar rich hydrolysates produced by acid hydrolysis of CS and SCG. S. cerevisiae provided the best ethanol production from SCG hydrolysate (11.7 g/l, 50.2% efficiency). On the other hand, insignificant (<= 1.0 g/l) ethanol production was obtained from CS hydrolysate, for all the evaluated yeast strains, probably due to the low sugars concentration present in this medium (approx. 22 g/l). It was concluded that it is possible to reuse SCG as raw material for ethanol production, which is of great interest for the production of this biofuel, as well as to add value to this agro-industrial waste. CS hydrolysate, in the way that is produced, was not a suitable fermentation medium for ethanol production; however, the hydrolysate concentration for the sugars content increase previous the use as fermentation medium could be an alternative to overcome this problem. (C) 2011 Elsevier Ltd. All rights reserved.
Resumo:
Low liquid-solid ratio (LSR) can be used to obtain high-content xylo-oligosaccharide (XOS) spend liquor by hot water pretreatment. Developing a technology based on low LSR results in more efficient water usage in the system and thus in lower capital and operating costs. Xylans from xylan rich agro-industrial waste are abundant hemicellulosic polymers with enormous potential for industrial applications. Currently, freeze-dried xylo-oligosaccharides are used as bio-based polymers and hydrolysates containing high xylose contents are converted to several chemical products. In this study, sugarcane bagasse was treated with water at low LSRs and mild temperatures in order to assess the effects of varying the pretreatment conditions on the xylo-oligosaccharide and xylose concentrations, and use a central composite experimental design to optimize the process parameters. The pretreatments were performed in the ranges temperature: 143.3-176.7 degrees C, time: 20-70 min and LSR: 1 : 1 to 11 : 1 (g g(-1)). The maximum concentrations of xylose and xylan were 13.76 and 36.18 g L-1 (equivalent to 48.29 g L-1 of xylan), respectively, which were achieved by treating bagasse at 170 degrees C for 60 min, with LSR of 3 g g(-1). The amount of xylan removed under these conditions was almost 57%. The soluble xylan consisted mainly of xylo-oligosaccharides (74 wt% of the identified compound in the spent liquor).
Resumo:
Three chemical species related to biomass burning, levoglucosan, potassium and water-soluble organic carbon (WSOC), were measured in aerosol samples collected in a rural area on the outskirts of the municipality of Ourinhos (Sao Paulo State, Brazil). This region is representative of the rural interior of the State, where the economy is based on agro-industrial production, and the most important crop is sugar cane. The manual harvesting process requires that the cane be first burned to remove excess foliage, leading to large emissions of particulate materials to the atmosphere. Most of the levoglucosan (68-89%) was present in small particles (<1.5 mu m), and its concentration in total aerosol ranged from 25 to 1186 ng m(-3). The highest values were found at night, when most of the biomass burning occurs. In contrast, WSOC showed no diurnal pattern, with an average concentration of 5.38 +/- 2.97 mu g m(-3) (n = 27). A significant linear correlation between levoglucosan and WSOC (r = 0.54; n = 26; p < 0.0001) confirmed that biomass burning was in fact an important source of WSOC in the study region. A moderate (but significant) linear correlation between levoglucosan and potassium concentrations (r = 0.62; n = 40; p < 0.0001) was indicative of the influence of other sources of potassium in the study region, such as soil resuspension and fertilizers. When only the fine particles (<1.5 pm; typical of biomass burning) were considered, the linear coefficient increased to 0.91 (n = 9). In this case, the average levoglucosan/K+ ratio was 0.24, which may be typical of biomass burning in the study region. This ratio is about 5 times lower than that previously found for Amazon aerosol collected during the day, when flaming combustion prevails. This suggests that the levoglucosan/K+ ratio may be especially helpful for characterization of the type of vegetation burned (such as crops or forest), when biomass-burning is the dominant source of potassium. The relatively high concentrations of WSOC (and inorganic ions) suggest an important influence on the formation of cloud condensation nuclei, which is likely to affect cloud formation and precipitation patterns. (C) 2012 Elsevier Ltd. All rights reserved.
Resumo:
Aspergillus phoenicis is an interesting heat tolerant fungus that can synthesize enzymes with several applications in the food industry due to its great hydrolytic potential. In this work, the fungus produced high enzymatic levels when cultivated on inexpensive culture media consisting of flakes from different origins such as cassava flour, wheat fibre, crushed soybean, agro-industrial wastes, starch, glucose or maltose. Several enzymatic systems were produced from these carbon sources, but amylase was the most evident, followed by pectinase and xylanase. Traces of CMCases, avicelase, lipase, β-xylosidase, β-glucosidase and α-glucosidase activities were also detected. Amylases were produced on rye flakes, starch, oat flakes, corn flakes, cassava flour and wheat fibre. Significant amylolytic levels were produced in the culture medium with glucose or when this sugar was exhausted, suggesting an enzyme in the constitutive form. Cassava flour, rye, oats, barley and corn flakes were also used as substrates in the hydrolytic reactions, aiming to verify the liberation potential of reducing sugars. Corn flakes induced greater liberation of reducing sugars as compared to the others. Thin layer chromatography of the reaction end products showed that the hydrolysis of cassava flour liberated maltooligosaccharides, but cassava flour and corn, rye, oats and barley flakes were hydrolyzed to glucose. These results suggested the presence of glucoamylase and α-amylase as part of the enzymatic pool of A. phoencis.
Resumo:
Brazil is considered one of the largest producers and consumers of tropical fruits. Green coconut (Cocos nucifera L.) stands out not only for its production and consumption, but also for the high amount of waste produced by coconut water industry and in natura consumption. Therefore, there is a need for utilization of this by-product. This study aims to study the adsorption isotherms of green coconut pulp and determine its isosteric heat of sorption. The adsorption isotherms at temperatures of 30, 40, 50, 60, and 70 °C were analyzed, and they exhibit type III behavior, typical of sugar rich foods. The experimental results of equilibrium moisture content were correlated by models present in the literature. The Guggenheim, Anderson and De Boer (GAB) model proved particularly good overall agreement with the experimental data. The heat of sorption determined from the adsorption isotherms increased with the decrease in moisture content. The heat of sorption is considered as indicative of intermolecular attractive forces between the sorption sites and water vapor, which is an important factor to predict the shelf life of dried products.
Resumo:
Abstract Background Guava pomace is an example of the processing waste generated after the manufacturing process from the juice industry that could be a source of bioactives. Thus, the present investigation was carried out in order to evaluate the anti-inflammatory and antinociceptive potential and determinate the main phenolic compounds of a guava pomace extract (GPE). Methods The anti-inflammatory activity was evaluated by carrageenan, dextran, serotonin, histamine-induced paw edema and neutrophils migration in the peritoneal cavity models. Acetic acid-induced abdominal writhing and formalin test were performed to investigate the antinociceptive effects. In addition, the content of total phenolic and of individual phenolic compounds was determined by GC/MS. Results GPE showed anti-inflammatory activity by carrageenan, dextran, serotonin, histamine-induced paw edema and neutrophils migration in the peritoneal cavity models (p < 0.05). GPE also demonstrated antinociceptive activity by acetic acid-induced abdominal writhing and formalin test (p < 0.05). The total phenolic value was 3.40 ± 0.09 mg GAE/g and epicatechin, quercetin, myricetin, isovanilic and gallic acids were identified by GC/MS analysis. Conclusions The presence of bioactive phenolic compounds as well as important effects demonstrated in animal models suggest that guava pomace could be an interesting source of anti-inflammatory and analgesic substances.
Resumo:
A suinocultura destaca-se na economia brasileira. Contudo, avaliando-se o consumo interno da carne suína in natura, observa-se uma estagnação em patamares baixos. O artigo tem como objetivo analisar as principais iniciativas adotadas pelo Sistema Agroindustrial (SAG) da carne suína no Brasil visando sinalizar qualidade aos consumidores. Devido à marcante assimetria de informações, ressalta-se a importância da organização da cadeia produtiva, melhor direcionando esforços para a expansão do mercado interno. Este trabalho sugere ações visando aprimorar a coordenação deste SAG com vistas à melhoria na qualidade da carne ao consumidor e à redução da informalidade.