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61.
Seventy-five yearling bulls of the “Asturiana de los Valles” northern-Spanish beef breed (double-muscled, mh/mh, n = 24; heterozygous, mh/+, n = 26; normal, +/+, n = 25) were produced under intensive conditions and the effects of double-muscling genotype on trans-18:1 and CLA isomer profiles were examined. Total trans-18:1 contents, measured as percentages of total fatty acid methyl esters, were 10.98–15.07% in backfat and 8.64–9.46% in muscle, and the major isomer was 10t-18:1 in all animals. In mh/+ animals, 11t-18:1 was the second most abundant trans isomer in muscle whereas in mh/mh and +/+ animals 11t-18:1 and 13t/14t-18:1 were relatively similar. Total CLA percentages were 0.71–0.85% in backfat and 0.32–0.40% in muscle. The highest total CLA percentage found was in mh/+, intermediate in +/+ and lowest in mh/mh animals (P < 0.05). Heterozygous animals had significantly higher percentages of 9c,11t- (P < 0.01), 11t,13c- (P < 0.01) and 9c,11c-18:2 (P < 0.05) and also significantly higher percentages of the sum of 9c,11t-/11t,13c-/11t,13t-18:2. Overall, mh/+ animals produced meat with a slightly better trans and CLA profile (i.e., less 10t-18:1 and more 11t-18:1 and 9c,11t-18:2) than other genotypes, however, further improvements would still be necessary to achieve a profile with a positive health image. 相似文献
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Noelia Rodríguez Ana Torrado Sandra Cortés José Manuel Domínguez 《Journal of the science of food and agriculture》2010,90(10):1726-1734
BACKGROUND: Lactococcus lactis is an interesting microorganism with several industrial applications, particularly in the food industry. As well as being a probiotic species, L. lactis produces several metabolites with interesting properties, such as lactic acid (LA) and biosurfactants. Nevertheless, L. lactis is an especially demanding species since it has strong nutritional requirements, implying the use of complex and expensive culture media. RESULTS: The results showed the potential of L. lactis CECT‐4434 as a LA and biosurfactant producer. The economical cost of L. lactis cultures can be reduced by replacing the MRS medium by the use of two waste materials: trimming vine shoots as C source, and 20 g L?1 distilled wine lees (vinasses) as N, P and micronutrient sources. From the hemicellulosic fraction, 14.3 g L?1 LA and 1.7 mg L?1 surfactin equivalent were achieved after 74 h (surface tension reduction of 14.4 mN m?1); meanwhile, a simultaneous saccharification and fermentation process allowed the generation of 10.8 g L?1 LA and 1.5 mg L?1 surfactin equivalent after 72 h, reducing the surface tension by 12.1 units at the end of fermentation. CONCLUSIONS: Trimming vine shoots and vinasses can be used as alternative economical media for LA and cell‐bound biosurfactant production. Copyright © 2010 Society of Chemical Industry 相似文献
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Antonio González‐Sarrías Juan A. Giménez‐Bastida María T. García‐Conesa María B. Gómez‐Sánchez Noelia V. García‐Talavera Angel Gil‐Izquierdo Carmen Sánchez‐Álvarez Luis O. Fontana‐Compiano Juan P. Morga‐Egea Francisco A. Pastor‐Quirante Francisco Martínez‐Díaz Francisco A. Tomás‐Barberán Juan Carlos Espín 《Molecular nutrition & food research》2010,54(3):311-322
Epidemiology supports the important role of nutrition in prostate cancer (PCa) prevention. Pomegranate juice (PJ) exerts protective effects against PCa, mainly attributed to PJ ellagitannins (ETs). Our aim was to assess whether ETs or their metabolites ellagic acid and urolithins reach the human prostate upon consumption of ET‐rich foods and to evaluate the effect on the expression of three proliferation biomarkers. Sixty‐three patients with BPH or PCa were divided into controls and consumers of walnuts (35 g walnuts/day) or pomegranate (200 mL PJ/day) for 3 days before surgery. Independently of the ETs source, the main metabolite detected was urolithin A glucuronide, (3,8‐dihydroxy‐6H‐dibenzo[b,d]pyran‐6‐one glucuronide) (up to 2 ng/g) together with the traces of urolithin B glucuronide, (3‐hydroxy‐6H‐dibenzo[b,d]pyran‐6‐one glucuronide) and dimethyl ellagic acid. The small number of prostates containing metabolites was likely caused by clearance of the compounds during the fasting. This was corroborated in a parallel rat study and thus the presence of higher quantities of metabolites at earlier time points cannot be discarded. No apparent changes in the expression of CDKN1A, MKi‐67 or c‐Myc were found after consumption of the walnuts or PJ. Our results suggest that urolithin glucuronides and dimethyl ellagic acid may be the molecules responsible for the beneficial effects of PJ against PCa. 相似文献
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Solar photocatalytic degradation of some hazardous water-soluble pesticides at pilot-plant scale 总被引:1,自引:0,他引:1
Oller I Gernjak W Maldonado MI Pérez-Estrada LA Sánchez-Pérez JA Malato S 《Journal of hazardous materials》2006,138(3):507-517
The technical feasibility and performance of photocatalytic degradation of six water-soluble pesticides (cymoxanil, methomyl, oxamyl, dimethoate, pyrimethanil and telone) have been studied at pilot-plant scale in two well-defined systems which are of special interest because natural solar UV light can be used: heterogeneous photocatalysis with titanium dioxide and homogeneous photocatalysis by photo-Fenton. TiO(2) photocatalysis tests were performed in a 35L solar pilot plant with three Compound Parabolic Collectors (CPCs) under natural illumination and a 75L solar pilot plant with four CPC units was used for homogeneous photocatalysis tests. The initial pesticide concentration studied was 50 mg L(-1) and the catalyst concentrations employed were 200 mg L(-1) of TiO(2) and 20 mg L(-1) of iron. Both toxicity (Vibrio fischeri, Biofix) and biodegradability (Zahn-Wellens test) of the initial pesticide solutions were also measured. Total disappearance of the parent compounds and nearly complete mineralization were attained with all pesticides tested. Treatment time, hydrogen peroxide consumption and release of heteroatoms are discussed. 相似文献
66.
Lipase production by solid‐state fermentation of olive pomace in tray‐type and pressurized bioreactors 下载免费PDF全文
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The development of inhibitors for hydrochloric acidic media is very common. Potassium iodide, in combination with some organic inhibitors, may transform a mediocre inhibitor into an excellent corrosion inhibitor based on a synergetic effect. There is a need to study what happens at the interface in the presence of this compound. The dynamics of the metal electrolyte interface when KI concentration increases has been characterized. The present study has been carried out based on electrochemical impedance spectroscopy and electrochemical noise analysis in the light of nonlinear phenomena by applying recurrence plots and fractal geometry. The fractal dimension of the current–time series shows a direct relationship with the fractal dimension of the surface of steel. The phenomenon of self-organization has been observed on the metal surface. The nonlinear analysis carried out by means of recurrence plots showed that the iodide ions' inhibitory effect is not only simple adsorption but also a nonlinear phenomenon that auto-organizes. The degree of complexity increases, consequently causing an interaction between the microcells and resulting in a lower charge-transfer rate. 相似文献
70.
Noelia Flórez Enma Conde Herminia Domínguez 《Journal of chemical technology and biotechnology (Oxford, Oxfordshire : 1986)》2015,90(4):590-607
The development of environmentally friendly processes with limited generation of polluting streams to attain sustainable utilization of raw materials is encouraged. The implementation of novel extraction technologies more efficient, selective and with lower energy consumption than conventional ones, can help in achieving this objective. Particularly promising are aqueous based methods, since water is a cheap, safe and abundant solvent and the limited use of toxic organic solvents is a consumer's, ecological and processing demand. The benefits and the limiting aspects of microwave assisted water extraction, either adding water as the only solvent or in solvent free processes, using the naturally present water in vegetal materials for the extraction of valuable components from renewable vegetal sources are highlighted and the potential of this technique for industrial applications is discussed. © 2014 Society of Chemical Industry 相似文献