Background: The utilization of methane for production of Poly-β-hydroxybutyrate (PHB) not only cuts the emissions of greenhouse gases but also greatly reduces PHB production cost. Objectives: The aim of this study was to determine the effects of gas-phase conditions on PHB production by Methylosinus trichosporium OB3b. Ma...

Flavor quality of Liriopis tuber tea that was made using a steaming process was studied by measuring changes in headspace volatile compounds. Headspace volatile compounds of the prepared samples were isolated, separated and identified by the combined system of purge & trap, automatic thermal desorber, gas chromatography, and mass selective detector. As steaming frequencies were increased, the a...

A diploid and a haploid strain of Pichia anomala were tested for their biocontrol ability against the spoilage mould Penicillium roqueforti in glass tubes filled with grain at two water activities (aw). At aw 0.98, the two yeast strains grew and inhibited mould growth equally well and showed similar patterns of ethyl acetate production, reaching maximum values of 10-14 microg ml(-1) headspace. ...

The floral headspace compounds of Chinese Rosa rugosa germplasms that were isolated by an automated headspace sampler with built-in trap, and followed by gas chromatography-mass spectrometry for identification and quantification. Up to 33 volatile compounds were identified from the 23 rose germplasms, including nine alcohols, five esters, three alkanes, 10 terpenes, three aldehydes, two ketones...

This work provides a short and easy protocol that allows the analysis of both methanol and ethanol in the static headspace of olive oil. The procedure avoids any kind of sample pre-treatment beyond that of heating the oil to allow a maximum volatile concentration in the headspace of the vials. The method's LOD is 0.55 mg kg(-1) and its LOQ is 0.59 mg kg(-1). Advantages of this method are:•Simul...

Two methods for the extraction, identification and quantification of the highest occurrence and lowest perception threshold off-flavours in fifteen different samples of Brazilian Pilsner beers were developed. For this purpose, headspace solid phase microextraction in combination with a gas chromatography coupled to a mass spectrometric detection (HS-SPME-GC-MS) as well as headspace extraction i...

The volatiles released by several streptomycetes were collected by using a closed-loop stripping apparatus (CLSA) and analysed by GC-MS. The obtained headspace extracts of various species contained blastmycinone, a known degradation product of the fungicidal antibiotic, antimycin A(3b), and several unknown derivatives. The suggested structures of these compounds, based on their mass spectra and...

Headspace solid-phase microextraction has been applied to the analysis of volatile phenols in wine. Silica fibre coated with Carbowax-divinylbenzene was found to be more efficient at extracting these compounds than other fibres such as those coated with polydimethylsiloxane, polyacrylate, carboxen-polydimethylsiloxane, and polydimethylsiloxane-divinylbenzene. Different parameters such as extrac...

A gas chromatography (GC) method including a full evaporation headspace (FE-HS) sampling technique was developed for rapidly and simultaneously measuring volatile products for acetone-butanol-ethanol (ABE) fermentation. In this method, a small volume (<50 μL) of fermentation broth was directly injected into a sealed headspace sample vial (22 mL) and the mass transfer of acetone-butanol-ethanol ...

A simple, rapid, accurate, and practical headspace gas chromatographic method is proposed for the determination of hydrogen peroxide residues in bleaching effluent. This method is based on the reaction of hydrogen peroxide with ceric sulfate, under acidic conditions, where hydrogen peroxide is converted to oxygen, which is then measured using headspace gas chromatography (HS-GC) coupled with a ...