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Alpha-cyclodextrin glucosyltransferase (α-CGTase, EC 2.4.1.19) is an amylolytic enzyme used for the production of α-cyclodextrin (α-CD), a novel, soluble dietary fiber, from food-grade starch. The safety of an α-CGTase preparation obtained by batch fermentation from a recombinant strain of Escherichia coli K12 harboring the α-CGTase gene from Klebsiella oxytoca strain M5a1 was examined. In a 13-week subchronic toxicity study in rats, the administration by gavage of the α-CGTase preparation at levels of up to 20 ml/kg bw/day, corresponding to a total organic solids dosage of 260 mg/kg bw/day, did not cause any systemic toxic effect. Some signs of irritation were observed in the respiratory tract which occurred, however, in one sex only and/or were not dose-related. Accordingly, these changes were considered to be an unspecific consequence of the reflux and aspiration of the dosing solution. There was no evidence of a genotoxic activity in Ames tests and a chromosome aberration test in cultured human lymphocytes. It is concluded that the examined α-CGTase preparation is safe when used for the production of α-CD. [Copyright &y& Elsevier]

Highlights: [•] Microarray was used to identify markers to detect pertussis toxin in six human cell types. [•] Immature monocyte-derived dendritic cells (iMoDCs) responded to pertussis toxin. [•] PTx-responsive gene profile in iMoDCs: IFNG, IL2, XCL1, CD69, CSF2 and CXCL10. [•] PTx-induced IL-2 and IFN-γ responses in iMoDCs were sensitive and specific compared to pertussis toxoid, LPS and LOS. [•] IL2 is a promising candidate to be used as a biomarker for the detection of residual PTx. [Copyright &y& Elsevier]

Abstract: The objective of this study was to determine the genotoxic activity of water after UV/H2O2 oxidation and GAC filtration. Pre-treated surface water from three locations was treated with UV/H2O2 with medium pressure (MP) lamps and passed through granulated activated carbon (GAC). Samples taken before and after each treatment step were extracted and concentrated by solid phase extraction (SPE) and analyzed for genotoxicity using the Comet assay with HepG2 cells and the Ames II assay. The Comet assay showed no genotoxic response in any of the samples. In the Ames II, no genotoxic response was obtained with the TAMix (a mix of six strains), but the TA98 strain showed an increase in genotoxic activity after MP-UV/H2O2 for all three locations. GAC post treatment effectively reduced the activities to control levels at two of the three locations and to below the level of the pre-treated water at one site. The results indicate that UV/H2O2 treatment may lead to the formation of genotoxic by-products, which can be removed by subsequent GAC filtration. [ABSTRACT FROM AUTHOR]