Santas J.,AB BIOTICS SA |
Guzman Y.J.,University of Barcelona |
Guardiola F.,University of Barcelona |
Rafecas M.,University of Barcelona |
And 2 more authors.
Food Chemistry | Year: 2014
A fluorometric method for the determination of hydroperoxides (HP) in edible oils and fats using the reagent diphenyl-1-pyrenylphosphine (DPPP) was developed and validated. Two solvent media containing 100% butanol or a mixture of chloroform/methanol (2:1, v/v) can be used to solubilise lipid samples. Regardless of the solvent used to solubilise the sample, the DPPP method was precise, accurate, sensitive and easy to perform. The HP content of 43 oil and fat samples was determined and the results were compared with those obtained by means of the AOCS Official Method for the determination of peroxide value (PV) and the ferrous oxidation-xylenol orange (FOX) method. The proposed method not only correlates well with the PV and FOX methods, but also presents some advantages such as requiring low sample and solvent amounts and being suitable for high-throughput sample analysis. © 2014 Elsevier Ltd. All rights reserved.
Rodriguez-Bencomo J.J.,Institute Investigacion En Ciencias Of La Alimentacion Cial Csic Uam |
Munoz-Gonzalez C.,Institute Investigacion En Ciencias Of La Alimentacion Cial Csic Uam |
Martin-Alvarez P.J.,Institute Investigacion En Ciencias Of La Alimentacion Cial Csic Uam |
Lazaro E.,AB BIOTICS SA |
And 3 more authors.
Food Analytical Methods | Year: 2012
The optimization of the main experimental variables, such as extraction temperature, volume of sample and the extraction time of an HS-SPME/GC-MS procedure, for profiling beer volatile analysis was evaluated using response surface methodology. A central composite circumscribed design was employed to study the effect of the experimental variables on the extraction of 28 representative volatile compounds of beer flavour profile. The parameters of the models were estimated by multiple linear regressions. The strongest influence in the volatile extraction yield was the volume of the sample (V) and the extraction temperature (T), with a positive and a negative effect, respectively. The performance characteristics of the optimised method were also determined, showing adequate linear ranges, repeatability, detection and quantification limits. The optimised methodology was applied to the same beer sample stored during 5 months at three different temperature conditions (4, 20 and 40 °C). Sampling was performed monthly, and the results showed that the concentration of most volatile compounds decreased during beer storage, although the rate of decrease was clearly higher at room temperature (20 °C) compared with refrigeration conditions (4 °C). Accelerated ageing conditions (40 °C) showed the most different volatile profile. Sensory analysis also revealed large differences in the overall quality of the samples, showing that even at room temperature the aroma profile of beer is greatly modified during its shelf life. © 2012 Springer Science+Business Media, LLC.
Tuson M.,Sloan Kettering Institute |
Tuson M.,AB BIOTICS SA |
He M.,Sloan Kettering Institute |
He M.,Cornell University |
Anderson K.V.,Sloan Kettering Institute
Development | Year: 2011
Protein kinase A (PKA) is an evolutionarily conserved negative regulator of the hedgehog (Hh) signal transduction pathway. PKAis known to be required for the proteolytic processing event that generates the repressor forms of the Ci and Gli transcriptionfactors that keep target genes off in the absence of Hh. Here, we show that complete loss of PKA activity in the mouse leads tomidgestation lethality and a completely ventralized neural tube, demonstrating that PKA is as strong a negative regulator of thesonic hedgehog (Shh) pathway as patched 1 (Ptch1) or suppressor of fused (Sufu). Genetic analysis shows that although PKA isimportant for production of the repressor form of Gli3, the principal function of PKA in the Shh pathway in neural developmentis to restrain activation of Gli2. Activation of the Hh pathway in PKA mutants depends on cilia, and the catalytic and regulatorysubunits of PKA are localized to a compartment at the base of the primary cilia, just proximal to the basal body. The data showthat PKA does not affect cilia length or trafficking of smoothened (Smo) in the cilium. Instead, we find that there is a significantincrease in the level of Gli2 at the tips of cilia of PKA-null cells. The data suggest a model in which PKA acts at the base of thecilium after Gli proteins have transited the primary cilium; in this model the sequential movement of Gli proteins betweencompartments in the cilium and at its base controls accessibility of Gli proteins to PKA, which determines the fates of Gli proteinsand the activity of the Shh pathway. © 2011.
Ab Biotics S.A. | Date: 2015-05-05
Bosch M.,AB BIOTICS SA |
Fuentes M.C.,AB BIOTICS SA |
Audivert S.,AB BIOTICS SA |
Bonachera M.A.,AB BIOTICS SA |
And 2 more authors.
Journal of the Science of Food and Agriculture | Year: 2014
BACKGROUND: Hypercholesterolaemia plays a key role in the development and progression of coronary artery disease. There are numerous drugs available to treat this condition but they are often expensive and can have unwanted side effects. Therefore, a screening of lactic acid bacteria to select candidate probiotic strains to reduce cholesterol levels was carried out. Three Lactobacillus plantarum strains (CECT 7527, 7528 and 7529) were selected as potential probiotics to reduce cholesterol levels after conducting several in vitro tests for demonstrating the functionalities of the strains according to international guidelines. RESULTS: The three strains showed a high ability to survive under gastrointestinal tract conditions and to adhere to intestinal cells. Regarding lipid metabolism, the strains showed a great production of bile salt hydrolase, especially when combined. Moreover, the strains assimilated cholesterol directly from the medium. Part of the cholesterol present in the medium was removed via binding onto the bacterial cellular surface. Finally, the three strains, especially CECT 7529, produce large quantities of propionic and butyric acids. CONCLUSION: Combined, these characteristics suggest that these strains could be excellent candidates for reducing high blood cholesterol levels. © 2013 Society of Chemical Industry.