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A simple sample preparation method requiring minimal organic solvents is proposed for the determination of the total phthalate content in cosmetics by high-performance liquid chromatography-tandem mass spectrometry. The hydrolysis of phthalates and purification of interfering substances were performed in a three-phase system that included an upper n-hexane phase, a middle ethanol phase, and a lower aqueous alkali solution. This three-phase system utilized an incremental purification strategy. The apolar ingredients were extracted with n-hexane, the polar pigments accumulated in the ethanol phase, and the hydrolysis product, phthalic acid, remained in the hydrolysate. Under the optimized conditions, the correlation coefficients ( r) for the calibration curves were 0.998-0.999 in the range 0.60-12 mol L. The limit of detection was 5.1 μmol kg, and the limit of quantification was 9.2 μmol kg. The recoveries varied from 84 to 97% with RSDs equal to or lower than 11%. The intra-day and inter-day repeatability values, expressed as the relative standard deviation, were less than 8.7 and 9.8, respectively. No obvious matrix effect existed in the different cosmetics matrices. The validated method was applied for the analysis of 57 commercial cosmetic samples. [ABSTRACT FROM AUTHOR]

For the analysis of edible oils, saponification is well known as a useful method for eliminating oil matrices. The conventional approach is conducted with alcoholic alkali; it consumes a large volume of organic solvents and impedes the retrieval of analytes by microextraction. In this study, a low-organic-solvent-consuming method has been developed for the analysis of benzo[a]pyrene in edible oils by high-performance liquid chromatography with fluorescence detection. Sample treatment involves aqueous alkaline saponification, assisted by a phase-transfer catalyst, and selective in situ extraction of the analyte with a supramolecular solvent. Comparison of the chromatograms of the oil extracts obtained by different microextraction methods showed that the supramolecular solvent has a better clean-up effect for the unsaponifiable matter from oil matrices. The method offered excellent linearity over a range of 0.03- 5.0 ng mL−1 ( r > 0.999). Recovery rates varied from 94 to 102% (RSDs <5.0%). The detection limit and quantification limit were 0.06 and 0.19 μg kg−1, respectively. The proposed method was applied for the analysis of 52 edible oils collected online in China; the analyte contents of 23 tested oil samples exceeded the maximum limit of 2 μg kg−1 for benzo[a]pyrene set by the Commission Regulation of the European Union. [ABSTRACT FROM AUTHOR]

The decrease in the content of higher alcohols and the increase in the ester content in alcoholic drinks are normally achieved by the aging process over years. This study examined the capability of some strains of Geotrichum spp. to complete this process within a few days. Four Geotrichum spp. strains (S12, S13, TM and TF) were separately added to one wine [containing 11.5% (v/v) ethanol] and to three liquor samples [containing 45, 50 and 55% (v/v) ethanol] and incubated at 28 and 15°C for 4 days. Significant increases in the ester content and decreases in the higher alcohols were observed with strains S12 and TM, in all treatments. Strains S13 and TF increased the ester content in the wine, but not in the liquors. Comparatively, most volatile compounds were found in the red wine treated with S12 at 15°C and in the liquor containing 55% (v/v) ethanol treated with TM at 28°C. The conversion from higher alcohols to their corresponding acids and esters was identified using gas chromatography coupled with mass spectrometry during the treatments. By comparing the results when enzyme extracts and whole cells were used, it was found that the decrease in the levels of the higher alcohols might be caused both by cell adsorption and enzymatic reactions, whereas the increase in the esters was caused mainly by enzymatic reactions. Copyright © 2016 The Institute of Brewing & Distilling [ABSTRACT FROM AUTHOR]

Pinoresinol diglucoside (PDG) and pinoresinol (Pin) are normally produced by plant cells via the phenylpropanoid pathway. This study reveals the existence of a related pathway in Phomopsis sp. XP-8, a PDG-producing fungal strain isolated from the bark of the Tu-chung tree (Eucommiaulmoides Oliv.). After addition of 0.15 g/L glucose to Phomopsis sp. XP-8, PDG and Pin formed when phenylalanine, tyrosine, leucine, cinnamic acid, and p-coumaric acid were used as the substrates respectively. No PDG formed in the absence of glucose, but Pin was detected after addition of all these substrates except leucine. In all systems in the presence of glucose, production of PDG and/or Pin and the accumulation of phenylalanine, cinnamic acid, or p-coumaric acid correlated directly with added substrate in a time- and substrate concentration- dependent manner. After analysis of products produced after addition of each substrate, the mass flow sequence for PDG and Pin biosynthesis was defined as: glucose to phenylalanine, phenylalanine to cinnamic acid, then to p-coumaric acid, and finally to Pin or PDG. During the bioconversion, the activities of four key enzymes in the phenylpropanoid pathway were also determined and correlated with accumulation of their corresponding products. PDG production by Phomopsis sp. exhibits greater efficiency and cost effectiveness than the currently-used plant-based system and will pave the way for large scale production of PDG and/or Pin for medical applications. [ABSTRACT FROM AUTHOR]

Copyright of Journal of Food Science (John Wiley & Sons, Inc.) is the property of John Wiley & Sons, Inc. and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Journal of Food Science (John Wiley & Sons, Inc.) is the property of John Wiley & Sons, Inc. and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Alicyclobacillus acidoterrestris can survive the pasteurization process, multiply in pasteurized juices and produce guaiacol which causes medicinal or antiseptic off-flavors. Chemical preservatives have the potential to suppress outgrowth of surviving populations during subsequent storage of fruit juices. In the present study, the individual effects of potassium sorbate, sodium benzoate, potassium metabisulfite, dehydroacetic acid, ethyl 4-hydroxybenzoate, cinnamic acid and ε-polylysine on A. acidoterrestris growth and guaiacol production were firstly evaluated in a laboratory medium. Of the seven preservatives investigated, only dehydroacetic acid, cinnamic acid and ε-polylysine were effective both in controlling growth and guaiacol formation by A. acidoterrestris . Then, these three antimicrobials were applied to apple juice. Through the addition of 270 mg/L dehydroacetic acid, 108 mg/L cinnamic acid or 100 mg/L ε-polylysine, the A. acidoterrestris counts were reduced by 3.43, 3.17 and 4.78 log colony forming unit (CFU)/mL, respectively, and no guaiacol was detected after 14 days of storage. Sensory evaluation revealed that the addition of these three preservatives did not affect the organoleptic properties of the apple juice. Results obtained in this paper could be very useful for a better control of A. acidoterrestris -related spoilage in the fruit juice/beverage industry. [ABSTRACT FROM AUTHOR]

Alicyclobacillus acidoterrestris has recently received much attention due to its implication in the spoilage of pasteurized fruit juices, which was manifested by the production of guaiacol. Vanillic acid and vanillin have been accepted as the biochemical precursors of guaiacol in fruit juices. The purpose of this study was to try to find other precursors and elucidate details about the conversion of vanillic acid and vanillin to guaiacol by A . acidoterrestris . Four potential substrates including ferulic acid, catechol, phenylalanine and tyrosine were analyzed, but they could not be metabolized to guaiacol by all the thirty A . acidoterrestris strains tested. Resting cell studies and enzyme assays demonstrated that vanillin was reduced to vanillyl alcohol by NADPH-dependent vanillin reductase and oxidized to vanillic acid by NAD(P) + -dependent vanillin dehydrogenases in A . acidoterrestris DSM 3923. Vanillic acid underwent a nonoxidative decarboxylation to guaiacol. The reversible vanillic acid decarboxylase involved was oxygen insensitive and pyridine nucleotide-independent. [ABSTRACT FROM AUTHOR]

Identification and evaluation of safety of forchlorfenuron ((1-(2-chloro-4-pyridyl)-3-phenylurea)), 1, metabolites after biotransformation in kiwifruit is the objective of this study. To elucidate properties of these metabolites, liquid chromatography hybrid ion trap time-of-flight mass spectrometry (LC-IT-TOF-MS) was applied, with MetID Solution and Formula Predictor Software in positive mode. Cytotoxicity of forchlorfenuron and its metabolites were tested through sulforhodamine B assays against normal Chinese hamster ovary cells (CHO). As deduced from characteristic fragment ions of forchlorfenuron, then confirmed by comparison with synthetic standards, as well as characterized by NMR and mass spectrometry techniques, results indicate the presence of 4-hydroxyphenyl-forchlorfenuron, 2, 3-hydroxyphenyl-forchlorfenuron, 3, and forchlorfenuron-4-O-β-D-glucoside, 5. Forchlorfenuron (IC50 = 12.12 ± 2.14 μM) and 4-hydroxyphenyl-forchlorfenuron (IC50 = 36.15 ± 1.59 μM), exhibits significant cytotoxicity against CHO, while 3-hydroxyphenyl-forchlorfenuron and forchlorfenuron-4-O-β-D-glucoside show no cytotoxicity.