Pseudomonas pseudoalcaligenes CECT5344, a cyanide-degrading bacterium with by-product (polyhydroxyalkanoates) formation capacity.

Background: Cyanide is one of the most toxic chemicals produced by anthropogenic activities like mining and jewelry industries, which generate wastewater residues with high concentrations of this compound. Pseudomonas pseudoalcaligenes CECT5344 is a model microorganism to be used in detoxification of industrial wastewaters containing not only free cyanide (CN(-)) but also cyano-derivatives, such as cyanate, nitriles and metal-cyanide complexes. Previous in silico analyses suggested the existence of genes putatively involved in metabolism of short chain length (scl-) and medium chain length (mcl-) polyhydroxyalkanoates (PHAs) located in three different clusters in the genome of this bacterium.

Phenylalanine ammonia-lyase, flavanone 3β-hydroxylase and flavonol synthase enzyme activity by a new in vitro assay method in berry fruits.

An HPLC method for the determination of phenylalanine ammonia-lyase, flavanone 3β-hydroxylase and flavonol synthase enzyme activity is proposed. This method is based on the determination of the compounds produced and consumed on the enzymatic reaction in just one chromatographic analysis. Optimisation of the method considered kinetic studies to establish the incubation time to perform the assay.

A new approach based on off-line coupling of high-performance liquid chromatography with gas chromatography-mass spectrometry to determine acrylamide in coffee brew.

A new method based on off-line coupling of LC with GC in replacement of conventional sample preparation techniques is proposed to analyze acrylamide in coffee brews. The method involves the preseparation of the sample by LC, the collection of the selected fraction, its concentration under nitrogen, and subsequent analysis by GC coupled with MS. The composition of the LC mobile phase and the flow rate were studied to select those conditions that allowed separation of acrylamide without coeluting compounds.

Evaluation of pesticide residue contents in fruit juice by solid-phase microextraction and multidimensional gas chromatography coupled with mass spectrometry.

A new method based on the use of SPME followed by the MDGC-MS analysis was developed to determine pesticides in fruit juice. Different pesticide mixture standards (i.e.

(+)-methyl jasmonate-induced bioformation of myricetin, quercetin and kaempferol in red raspberries.

The effect of postharvest treatment with enantiomers of methyl jasmonate (MJ) in conjunction with ethanol on bioformation of myricetin, quercetin and kaempferol in red raspberry was studied. For comparison, postharvest treatment with the commercial stereoisomeric mixture of MJ in conjunction with ethanol was simultaneously accomplished. The levels obtained were contrasted with those determined in untreated (control) samples.

Impact of postharvest methyl jasmonate treatment on the volatile composition and flavonol content of strawberries.

Background: Although strawberry aroma is very complex, certain compounds have been described as main contributors, i.e. furanones, aldehydes, alcohols, sulfur compounds and particularly methyl and ethyl esters.

Development of a method based on on-line reversed phase liquid chromatography and gas chromatography coupled by means of an adsorption-desorption interface for the analysis of selected chiral volatile compounds in methyl jasmonate treated strawberries.

A method based on the use of the through oven transfer adsorption-desorption (TOTAD) interface in on-line coupling between reversed phase liquid chromatography and gas chromatography (RPLC-GC) for the determination of chiral volatile compounds was developed. In particular, the method was applied to the study of the influence of methyl jasmonate (MJ) treatment on the production and enantiomeric composition of selected aroma compounds in strawberry. The compounds studied were ethyl 2-methylbutanoate, linalool and 4-hydroxy-2,5-dimethyl-3(2H)-furanone (i.