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991.
Boleti AP Freire Md Coelho MB Silva Wd Baldasso PA Gomes VM Marangoni S Novello JC Macedo ML 《Journal of agricultural and food chemistry》2007,55(7):2653-2658
This paper describes the purification and characterization of a novel protein from the seeds of Pouteria torta (family Sapotaceae). The protein was purified by a combination of gel filtration, ion-exchange, and reverse phase chromatographies. SDS-PAGE of the purified protein resulted in a single protein band of 14 kDa in the presence and absence of DTT. The lectin-like activity of pouterin was best inhibited by glycoproteins such as fetuin, asialofetuin, heparin, orosomucoid, and ovoalbumin. Pouterin inhibited the growth of the fungi Fusarium oxysporum and Colletotrichum musae and of the yeast Saccharomyces cerevisiae. The incorporation of pouterin into an artificial diet (final concentration = 0.12%, w/w) caused 50% mortality in larvae of the insect Callosobruchus maculatus, whereas 0.08% pouterin produced an ED50. 相似文献
992.
Rodríguez G Rodríguez R Jiménez A Guillén R Fernandez-Bolaños J 《Journal of agricultural and food chemistry》2007,55(1):136-142
The solid waste from two-phase olive oil extraction or "alperujo" was submitted to steam treatment at high pressure or temperature, 200 degrees C for 5 min, in the presence and absence of mild acid catalyst. This treatment made easier the separation of the solid and liquid fractions. Besides the recovery of certain valuable components from the liquid fraction (the antioxidant hydroxytyrosol, low molecular weight oligosaccharides, glucose, mannitol, etc.), the major components of the solid residue could be also exploited. In this study, changes in composition of alperujo due to steam treatment were determined. The process reduced appreciably the hemicellulose concentrations (75-88%), removed a substantial portion of Klason lignin and protein (50%), and led to an extensive solubilization of alperujo (55-67%). Cellulose was very resistant to autohydrolysis and acid-catalyzed hydrolysis, so the solid residue was enriched in fat (13-18 g/100 g of dry steam-treated alperujo) and cellulose (15-25 g/100 g of dry and defatted steam-treated alperujo). The steam-treated material can be efficiently saccharified with commercial cellulase. The best hydrolysis yields were attained, up to 80%, when the treated material was post-treated with NaOH. The possibility of using this steam-treated alperujo in animal feeding was evaluated by an in vitro digestibility test, using the pepsin-cellulase method. The treatment affected positively the nutritional characteristics of alperujo with an increase in its in vitro (dry and organic matter) digestibility (8-10% higher than untreated material). In vitro digestibility and cellulose accessibility to enzymatic hydrolysis were improved by the alkali post-treatment. 相似文献
993.
Moldes AB Torrado AM Barral MT Domínguez JM 《Journal of agricultural and food chemistry》2007,55(11):4481-4486
The cost of biosurfactant production may be significantly decreased by using inexpensive carbon substrates like agricultural residues. However, scarce information can be found in the literature about the utilization of lignocellulosic residues for obtaining biosurfactants. Usually agricultural residues are field burned, producing various toxic compounds to the atmosphere; so, as an interesting alternative to the traditional field burning of this kind of residue, this work proposes the utilization of agricultural wastes (barley bran, trimming vine shoots, corn cobs, and Eucalyptus globulus chips) for simultaneous lactic acid and biosurfactant production. Previous to this biotechnological process, lignocellulosic residues were hydrolyzed, using H2SO4, under selected conditions and neutralized with CaCO3. Following, Lactobacillus pentosus was employed for the fermentation of hemicellulosic hydrolyzates after nutrient supplementation. Biosurfactants were measured by taking into account the surface tension reduction. The highest value of reduction (21.3 units) was found when using hemicellulosic sugar hydrolyzates obtained from trimming vine shoots, corresponding to 0.71 g of biosurfactant per g of biomass and 25.6 g of lactic acid/L. On the contrary, barley bran husk hydrolyzates only produced 0.28 g of biosurfactant per g of biomass and 33.2 g of lactic acid/L. The differences between biosurfactant production can be attributed to the different compositions of the hydrolyzates. 相似文献
994.
Báidez AG Gómez P Del Río JA Ortuño A 《Journal of agricultural and food chemistry》2007,55(9):3373-3377
Xylem ultrastructural modification and the possible participation of phenolic compounds in the natural defense or resistance mechanisms of olive plants infected with Verticillium dahliae Kleb. were studied. Microscopic study showed that the mycelium propagated and passed from one element to another through the pit. The formation of tyloses and aggregates contributed to obstruction of the xylem lumen. In vivo changes in the levels of these phenolic compounds in infected olive plants and their antifungal activity against Verticillium dahliae Kleb., as revealed by in vitro study, strongly suggest that they are involved in natural defense or resistance mechanisms in this plant material, the most active being quercetin and luteolin aglycons, followed by rutin, oleuropein, luteolin-7-glucoside, tyrosol, p-coumaric acid, and catechin. . 相似文献
995.
Jacques RA Arruda EJ de Oliveira LC de Oliveira AP Dariva C de Oliveira JV Caramão EB 《Journal of agricultural and food chemistry》2007,55(18):7510-7516
The influence of agronomic variables (light intensity, age of leaves, and fertilization type) on the content of macronutrients and micronutrients (potassium, calcium, sodium, magnesium, manganese, iron, zinc, and copper) of tea leaves was assessed by acid digestion, followed by flame atomic absorption spectrometry (FAAS). The thermal behavior of mate tea leaves (Ilex paraguariensis) was also studied in this work. Samples of mate (Ilex paraguariensis) were collected in an experiment conducted under agronomic control at Erva-Mate Bar?o Commerce and Industry LTD (Brazil). The results showed that the mineral content in mate is affected by the agronomic variables investigated. In general, the content of mineral compounds analyzed is higher for younger leaves and for plants cultivated in shadow. Thermal analysis of samples indicated a similar behavior, with three typical steps of decomposition: loss of water, degradation of low-molecular weight compounds, and degradation of residual materials. 相似文献
996.
Saito ST Gosmann G Saffi J Presser M Richter MF Bergold AM 《Journal of agricultural and food chemistry》2007,55(23):9409-9414
Freeze-dried extracts from Camellia sinensis var. assamica IAC-259 cultivar named Brazilian green tea were prepared by hot water and ultrasound-assisted extractions using leaves harvested in spring and summer. Their caffeine and catechin contents were measured by high performance liquid chromatography-diode array detector. The antioxidant activity of the major green tea compounds and Brazilian green tea extracts was evaluated using a 2,2-diphenyl-1-picrylhydrazyl (DPPH) assay. The levels of caffeine were higher in the summer samples (p < 0.05); otherwise, there were no significant variations related to the catechin contents between spring and summer samples. The sonication method using water/acetone as solvent had a high efficiency to extract not only epigallocatechin gallate but also epicatechin gallate (p < 0.05). Antioxidant activities of the Brazilian green tea extracts were not significantly different among seasons and extraction systems. The antioxidant data (IC50) of the Brazilian green tea extracts showed a significant correlation with their epigallocatechin gallate and epicatechin gallate contents (p < 0.05). 相似文献
997.
Alzate A Cañas B Pérez-Munguía S Hernández-Mendoza H Pérez-Conde C Gutiérrez AM Cámara C 《Journal of agricultural and food chemistry》2007,55(24):9776-9783
Selenium is an essential element in the human diet. Interestingly, there has been an increased consumption of dietary supplements containing this element in the form of either inorganic or organic compounds. The effect of using selenium as a dietary supplement in yogurt has been evaluated. For this purpose, different concentrations of inorganic Se (ranging from 0.2 to 5000 microg g(-1)) have been added to milk before the fermentation process. Biotransformation of inorganic Se into organic species has been carefully evaluated by ion-exchange, reversed-phase, or size-exclusion chromatography, coupled to inductively coupled plasma mass spectrometry (ICP-MS). Yogurt fermentation in the presence of up to 2 microg g(-1) of Se(IV) produces a complete incorporation of this element into proteins as has been demonstrated applying a dialysis procedure. Analysis by SEC-ICP-MS showed that most of them have a molecular mass in the range of 30-70 kDa. Species determination after enzymatic hydrolysis has allowed the identification of Se-cystine using two different chromatographic systems. The biotransformation process that takes place during yogurt fermentation is very attractive because yogurt can act as a source of selenium supplementation. 相似文献
998.
Rocha Ribeiro SM Queiroz JH Lopes Ribeiro de Queiroz ME Campos FM Pinheiro Sant'ana HM 《Plant foods for human nutrition (Dordrecht, Netherlands)》2007,62(1):13-17
This work was carried out to investigate the pulp composition of four mango cultivars (Haden, Tommy Atkins and Ubá) at the
ripening stage in relation to three components with antioxidant potential (total phenolics, carotenoids and ascorbic acid).
Total phenolic compound content was estimated by the Folin-Ciocalteu reagent and total carotenoid content by spectrophotometry
at 450 nm. The contents of β-carotene and total vitamin C (ascorbic acid and dehydroascorbic acid) were quantified by high performance liquid chromatography.
Differences were found among the four mango cultivars in all the components analyzed. The content of phenolic compounds ranged
from 48.40 (Haden) to 208.70 mg/100 g (Ubá); total carotenoid from 1.91 (Haden) to 2.63 mg/100 g (Palmer); β-carotene from 661.27 (Palmer) to 2,220 μg/100 g (Ubá) and total ascorbic acid ranged from 9.79 (Tommy Atkins) to 77.71 mg/100 g
(Ubá). These results corroborated previous information that mangoes are a good source of antioxidants in human diet. 相似文献
999.
Ana B. Casal María Camacho Luis F. López‐Jurado Candelaria Juste Jorge Orós 《Veterinary clinical pathology / American Society for Veterinary Clinical Pathology》2009,38(2):213-218
Background: Plasma biochemical and hematologic variables are important in the management of endangered sea turtles, such as loggerheads. However, studies on blood biochemistry and hematology of loggerheads are limited, and different concentrations according to variable criteria have been reported. Objective: The purpose of this study was to establish and compare baseline plasma chemistry and hematology values in Eastern Atlantic juvenile and adult nesting loggerhead sea turtles (Caretta caretta). Methods: Blood samples were collected from 69 healthy juvenile loggerhead sea turtles after their rehabilitation in captivity, and from 34 adult nesting loggerheads after oviposition. Fresh blood was used for leukocyte differential count and PCV determination. Heparinized blood was used for RBC and WBC counts. Plasma biochemical concentrations were measured using an automated biochemical analyzer. For the comparative study, nonparametric statistical analysis was done using the Mann–Whitney U‐test. Results: Minimum, maximum, and median concentrations were obtained for 14 hematologic and 15 plasma chemistry variables. Statistically significant differences between juvenile and adult turtles were found for PCV; RBC, WBC, and leukocyte differential counts; total protein, albumin, globulins, calcium, triglycerides, glucose, total cholesterol and urea concentrations; and lactate dehydrogenase activity. Conclusions: Age, size, and reproductive status cause important variations in the hematologic and plasma biochemical results of loggerheads. The reference values obtained in this study may be used as a standard profile, useful for veterinary surgeons involved in sea turtle conservation. 相似文献
1000.
Ana C. Mortari Sheila C. Rahal Luiz C. Vulcano Vicente Colombi da Silva Reinaldo S. Volpi 《The Canadian veterinary journal. La revue veterinaire canadienne》2009,50(10):1064-1068
This prospective study used radiographic techniques to evaluate the inclination, Norberg, quadriceps and femoral varus angles, and the patellar position in dogs with developmental medial patellar luxation. The study also compared these measurements pre- and post-operatively to determine how they were affected by surgical procedures. Eighteen dogs with unilateral or bilateral luxation were used, and 4 groups were established according to luxation grade. Except for the quadriceps angle, there was no difference among the groups preoperatively. Significant differences for the quadriceps angle were observed between Grades 1 and 3, and between Grades 2 and 3. The Norberg and femoral varus angles and the patellar position showed no changes between pre- and postoperative groups. However, measurements of the preoperative quadriceps angle and postoperative inclination angle may be useful for evaluating dogs with grade-3 luxation. Further studies using other imaging techniques are required in dogs with severe grade-4 luxation due to the difficulty in obtaining a good radiographic position. 相似文献