Determination of (fluoro)quinolones in eggs by liquid chromatography with fluorescence detection and confirmation by liquid chromatography-tandem mass spectrometry

A multiresidue analytical procedure for determination of seven fluoroquinolones (marbofloxacin, norfloxacin as internal standard, ciprofloxacin, danofloxacin, enrofloxacin, sarafloxacin and difloxacin), and three quinolones (oxolinic acid, nalidixic acid and flumequine) in eggs is presented. The procedure is based on dispersive solid-phase extraction technique with acetonitrile as extractant. Norfloxacin and ciprofloxacin - d8 were used as internal standards to quantify the (fluoro)quinolones. Analyses were realised by LC-FLD for screening and LC-MS/MS for confirmatory purposes. The whole procedure was evaluated according to the Commission Decision 2002/657/EC. Specificity, decision limit (CCα), detection capacity (CCβ), recovery (absolute and relative), precision (repeatability and reproducibility) were determined during validation process. Recoveries (relative) for the LC-FLD screening determination ranged from 85% to 93%, repeatability and reproducibility were in the range of 5-9% to 9-16%, respectively. CCα and CCβ were 13-37 and 17-43 μg/kg pending on analite. For the LC-MS/MS confirmatory method, the relative recoveries were satisfactory (92-99%) with repeatability and reproducibility in the range of 4-7% to 6-12%, respectively. CCα and CCβ were 3-7 and 7-11 μg/kg depending on the analite. The results of both prepared methods showed these analytical procedures simple, rapid, sensitive and suitable for routine control of eggs.     

Chemical characterization of 21 species of marine macroalgae common in Norwegian waters: benefits of and limitations to their potential use in food and feed

BACKGROUND

In the past few years, much effort has been invested into developing a new blue economy based on harvesting, cultivating and processing marine macroalgae in Norway. Macroalgae have high potential for a wide range of applications, e.g. as source of pharmaceuticals, production of biofuels or as food and feed. However, data on the chemical composition of macroalgae from Norwegian waters are scant. This study was designed to characterize the chemical composition of 21 algal species. Both macro‐ and micronutrients were analysed. Concentrations of heavy metals and the metalloid arsenic in the algae were also quantified.

RESULTS

The results confirm that marine macroalgae contain nutrients which are relevant for both human and animal nutrition, the concentrations whereof are highly dependent on species. Although heavy metals and arsenic were detected in the algae studied, concentrations were mostly below maximum allowed levels set by food and feed legislation in the EU.

CONCLUSION

This study provides chemical data on a wide range of algal species covering the three taxonomic groups (brown, red and green algae) and discusses both benefits of and potential limitations to their use for food and feed purposes. © 2017 The Authors. Journal of The Science of Food and Agriculture published by John Wiley & Sons Ltd on behalf of Society of Chemical Industry.     

Prediction of timber bending strength and in-member cross-sectional stiffness variation on the basis of local wood fibre orientation

Machine strength grading of structural timber is based upon relationships between so called indicating properties (IPs) and bending strength. However, such relationships applied on the market today are rather poor. In this paper, new IPs and a new grading method resulting in more precise strength predictions are presented. The local fibre orientation on face and edge surfaces of wooden boards was identified using high resolution laser scanning. In combination with knowledge regarding basic wood material properties for each investigated board, the grain angle information enabled a calculation of the variation of the local MOE in the longitudinal direction of the boards. By integration over cross-sections along the board, an edgewise bending stiffness profile and a longitudinal stiffness profile, respectively, were calculated. A new IP was defined as the lowest bending stiffness determined along the board. For a sample of 105 boards of Norway spruce of dimension 45 × 145 × 3,600 mm³, a coefficient of determination as high as 0.68–0.71 was achieved between this new IP and bending strength. For the same sample, the coefficient of determination between global MOE, based on the first longitudinal resonance frequency and the board density, and strength was only 0.59. Furthermore, it is shown that improved accuracy when determining the stiffness profiles of boards will lead to even better predictions of bending strength. The results thus motivate both an industrial implementation of the suggested method and further research aiming at more accurately determined board stiffness profiles.     

Household hazardous waste data for the UK by direct sampling

The amount of household hazardous waste (HHW) disposed of in the United Kingdom (UK) requires assessment. This paper describes a direct analysis study carried out in three areas in southeast England involving over 500 households. Each participating householder was provided with a special bin in which to place items corresponding to a list of HHW. The amount of waste collected was split into nine broad categories: batteries, home maintenance (DIY), vehicle upkeep, pesticides, pet care, pharmaceuticals, photographic chemicals, household cleaners, and printer cartridges. Over 1 T of waste was collected from the sample households over a 32-week period, which would correspond to an estimated 51,000 T if extrapolated to the UK population for the same period or over 7,000 T per month. Details of likely disposal routes adopted by householders were also sought, demonstrating the different pathways selected for different waste categories. Co-disposal with residual household waste dominated for waste batteries and veterinary medicines, hence avoiding classification as hazardous waste under new UK waste regulations. The information can be used to set a baseline for the management of HHW and provides information for an environmental risk assessment of the disposal of such wastes to landfill.     

Changes in rumen bacterial and archaeal communities over the transition period in primiparous Holstein dairy cows

In the present study, we hypothesized that the rumen bacterial and archaeal communities would change significantly over the transition period of dairy cows, mainly as an adaptation to the classical use of low-grain prepartum and high-grain postpartum diets. Bacterial 16S rRNA gene amplicon sequencing of rumen samples from 10 primiparous Holstein dairy cows revealed no changes over the transition period in relative abundance of genera such as Ruminococcus, Butyrivibrio, Clostridium, Coprococcus, and Pseudobutyrivibrio. However, other dominant genus-level taxa, such as Prevotella, unclassified Ruminococcaceae, and unclassified Succinivibrionaceae, showed distinct changes in relative abundance from the prepartum to the postpartum period. Overall, we observed individual fluctuation patterns over the transition period for a range of bacterial taxa that, in some cases, were correlated with observed changes in the rumen short-chain fatty acids profile. Combined results from clone library and terminal-restriction fragment length polymorphism (T-RFLP) analyses, targeting the methyl-coenzyme M reductase α-subunit (mcrA) gene, revealed a methanogenic archaeal community dominated by the Methanobacteriales and Methanomassiliicoccales orders, particularly the genera Methanobrevibacter, Methanosphaera, and Methanomassiliicoccus. As observed for the bacterial community, the T-RFLP patterns showed significant shifts in methanogenic community composition over the transition period. Together, the composition of the rumen bacterial and archaeal communities exhibited changes in response to particularly the dietary changes of dairy cows over the transition period.     

The effect of hydrothermic treatment on the physicochemical properties of rye grain

Summary The gelatinized, autoclaved and sodiumhydroxide-treated starch preparations were used and their interaction with soluble pentosans and gliadin was analysed. The molecular sieving technique and optical methods were used to detect the complexes formed. The modified starches formed complexes with both soluble pentosans and gliadin in acidic and neutral media (non-ionic molecular forces being involved). The autoclaved starch showed the highest reactivity. The amylose and amylopectin played different roles in the interactions and the aggregates of amylose with gliadin and amylopectin with soluble pentosans were the prevailing forms present in the complexes. Small quantities of other products were also identified.

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Einfluß der hydrothermischen Behandlung auf die physiko-chemischen Eigenschaften des RoggenkornsII. Wechselwirkung der Eiweiß-und Kohlenhydratkomplexe (Modelluntersuchung)

Zusammenfassung Die Wechselwirkungen verkleisterter, autoklavierter und mit Natronlauge behandelter Stärke mit löslichen Pentosanen und Gliadin werden mit Hilfe der Gelpermeation und mit optischen Methoden untersucht. Die modifizierten Stärken bildeten Komplexe mit den Pentosanen und mit Gliadin im sauren und neutralen Medium, autoklavierte Stärke zeigte die hächste Reaktion. Die unterschiedliche Rolle von Amylose und Amylopection zeigte vorherrschend Amylose-Gliadin und Amylopectin-PentosanKomplexe, während andere Komplexe in kleineren Mengen auftraten.

     

PROTEIN PRECIPITATION DURING WORT BOILING: QUALITY ASPECTS OF DIMINISHED WORT BOILING TIMES OF BREWS PREPARED FROM PROANTHOCYANIDIN-FREE OR REGULAR RAW MATERIALS

When using proanthocyanidin-free materials for the production of beer, a reduction of the wort boiling time can be considered. In worts prepared with regular malt and tannin-free hop extract there is a continuous precipitation of the malt flavanoids while in brews prepared from proanthocyanidin-free malt and regular hops there is a simultaneous extraction and removal of the hop flavanoids leading to constant levels of these hop flavanoids. The results also show that the level of Kjeldahl nitrogen in worts boiled with hops will be the same as that in worts boiled with n-hexane tannin-free hop extracts. These results and the fact that more protein precipitates in brews containing no malt or hop proanthocyanidins suggest that, unlike what is the case during the development of beer haze, polyphenols are not necessary for an effective protein precipitation during wort boiling.     

The thromboembolic risk of the pill

In this review, the clinical reality, the statistical risk, and the frequency of thromboembolism in pill users are evaluated, 6 cases described, and premonitory signs, treatment, and etiology are discussed. Clinically these thromboembolisms appear in unlikely subjects and unusual bodily locations such as the mesenteric veins, without warning. The risks are 8-11 times higher for pulmonary thrombosis, 3-6 times higher for myocardial infarction, based on previously used higher dosed pills. The frequency is about .5-1/1000, or 500-1000/year in France. Some of the cases described used pills with less than .05 mg estrogen, some were heavy smokers, 1 woman died, 1 had a lower extremity amputation, and 1 woman had demonstrated IgG lamda antibodies against ethinyl estradiol. Premonitory signs are rare, and unsually ignored. The immediate action is to stop the pill and start anticoagulants. The cause of these disorders is not known in detail, but is presumed to be estrogens, therefore, low-dose pills, i.e., those with .05 or .03 mg ethinyl estradiol, should be used if possible. Other risk factors are surgery, age, immobilization, history of vein disorders, smoking, hyperlipidemia, hypertension, especially since the pill potentiates hypertension, hyperlipidemia, and hypercoagulation. Some mechanisms proposed are hyperlipidemia, disturbed blood coagulation factors, decreased fibrinolysis, alterations in the blood vessel endothelium and immunity against the estrogen in the pill.