TY - JOUR A1 - Julsing, M.K. A1 - Fichera, Mario Augusto A1 - Malz, Frank A1 - Ebbelaar, M. A1 - Bos, R. A1 - Woerdenbag, H. J. A1 - Quax, W.J. A1 - Kayser, O. T1 - Bioconversion of Mono- and Sesquiterpenoids by recombinant human Cytochrome P450 Monooxygenases JF - Pharmaceutical biology N2 - Cytochrome P450 monooxygenases play an important role in the biosynthesis and metabolism of terpenoids. We explored the potential of recombinant human liver cytochrome P450 monooxygenases CYP1A2, CYP2C9, and CYP3A4, heterologously expressed in Escherichia coli, to convert mono- and sesquiterpenoids to human metabolites. This natural product group is a diverse class of secondary metabolites and includes several industrially and pharmaceutically interesting compounds. Incubation of cedrol with CYP3A4 resulted in a bioconversion of 74% (±8.9%) after 1 h of the unknown metabolites 2-hydroxycedrol and 4-hydroxycedrol, which have been structurally elucidated by 1H and 13C NMR and GC-MS. We conclude that recombinant human cytochrome P450 enzymes can be useful tools in a combinatorial biosynthesis strategy for the production of new natural products and for in vitro metabolization studies. KW - Cedrol KW - Cytochrome P450 KW - Drug metabolism KW - NMR KW - Terpenoids PY - 2008 DO - https://doi.org/10.1080/13880200802215487 SN - 1388-0209 SN - 1744-5116 VL - 46 IS - 10-11 SP - 710 EP - 718 PB - Informa Healthcare CY - New York, NY, USA AN - OPUS4-18912 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Fichera, Mario Augusto A1 - Braun, Ulrike A1 - Jäger, Christian A1 - Karrasch, Andrea A1 - Schartel, Bernhard T1 - Solid state NMR investigations of flame retardant HIPS system based on Mg(OH)2 with red phosphorus T2 - FRPM '05 in der BAM, BAM T2 - FRPM '05 in der BAM, BAM CY - Berlin, Germany DA - 2005-09-07 PY - 2005 AN - OPUS4-7399 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Fichera, Mario Augusto A1 - Braun, Ulrike A1 - Jäger, Christian A1 - Karrasch, Andrea A1 - Schartel, Bernhard T1 - A solid-state NMR study of thermal decomposition of flame retardant HIPS T2 - GDCh Magnetic Resonance Division, Max-Planck-Institute for Polymer Research T2 - GDCh Magnetic Resonance Division, Max-Planck-Institute for Polymer Research CY - Mainz, Germany DA - 2005-09-26 PY - 2005 AN - OPUS4-10877 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Fichera, Mario Augusto A1 - Jäger, Christian A1 - Braun, Ulrike A1 - Schartel, Bernhard T1 - NMR investigation of a special intermediate reaction product of heat treated flame retardant HIPS / Mg(OH)2 / Pr system T2 - NMR Symposium of the 48th Rocky Mountain Conference on Analytical Chemistry T2 - NMR Symposium of the 48th Rocky Mountain Conference on Analytical Chemistry CY - Breckenridge, CO, USA DA - 2006-07-23 PY - 2006 AN - OPUS4-12380 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Fichera, Mario Augusto A1 - Jäger, Christian A1 - Braun, Ulrike A1 - Schartel, Bernhard T1 - A solid state NMR investigation of the thermal decomposition process of the flame retardant HIPS / Mg(OH)2 / Pr system T2 - NMR Symposium of the 48th Rocky Mountain Conference on Analytical Chemistry T2 - NMR Symposium of the 48th Rocky Mountain Conference on Analytical Chemistry CY - Breckenridge, CO, USA DA - 2006-07-23 PY - 2006 AN - OPUS4-12375 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Fichera, Mario Augusto A1 - Jäger, Christian A1 - Braun, Ulrike A1 - Schartel, Bernhard T1 - NMR investigation of a solid intermediate reaction product of heat treated flame retardant HIPS/ Mg(OH)2/ Pr system T2 - "Principles and Novel Applications of Modem Magnetic Resonance Methods" 28. Diskussionstagung der GDCh-Fachgruppe Magnetische Resonanzspektroskopie T2 - "Principles and Novel Applications of Modem Magnetic Resonance Methods" 28. Diskussionstagung der GDCh-Fachgruppe Magnetische Resonanzspektroskopie CY - Tübingen, Germany DA - 2006-09-26 PY - 2006 AN - OPUS4-13807 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Fichera, Mario Augusto A1 - Jäger, Christian A1 - Panne, Ulrich A1 - Schartel, Bernhard A1 - Braun, Ulrike T1 - A solid state NMR study of the pyrolysis and thermo-oxidative decomposition products of flame retardant HIPS T2 - ANAKON 2007 GDCh Fachgruppe Analytische Chemie T2 - ANAKON 2007 GDCh Fachgruppe Analytische Chemie CY - Jena, Germany DA - 2007-03-27 PY - 2007 AN - OPUS4-14657 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Jäger, Christian A1 - Fichera, Mario Augusto A1 - Schartel, Bernhard A1 - Braun, Ulrike A1 - Pawlowski, Kristin T1 - Solid-State NMR for monitoring the thermal Decomposition of flame retarded polymers T2 - 49th Annual Rocky Mountain Conference on Analytical Chemistry, Beaver run Resort & Conference Center T2 - 49th Annual Rocky Mountain Conference on Analytical Chemistry, Beaver run Resort & Conference Center CY - Breckenridge, CO, USA DA - 2007-07-22 PY - 2007 AN - OPUS4-14687 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Braun, Ulrike A1 - Schartel, Bernhard A1 - Fichera, Mario Augusto A1 - Jäger, Christian T1 - Flame retardancy mechanisms of aluminium phosphinate in combination with melamine polyphosphate and zinc borate in glass-fibre reinforced polyamide 6,6 JF - Polymer degradation and stability N2 - The fire retardancy mechanisms of aluminium diethylphosphinate in combination with melamine polyphosphate and zinc borate was analysed in glass-fibre reinforced polyamide 6,6. The influence of phosphorus compounds on the polyamide decomposition pathways was characterized using thermal analysis (TG), evolved gas analysis (TG–FTIR), and FTIR–ATR analysis of the residue. The Lewis acid–base interactions between the flame retardants, the amide unit, and the metal ions control the decomposition. The flammability (LOI, UL 94) and performance under forced-flaming conditions (cone calorimeter using different irradiations) were investigated. Fire residues were analysed with FTIR–ATR, SEM–EDX, and NMR. Aluminium phosphinate in polyamide 6,6 acts mainly by flame inhibition. Melamine polyphosphate shows some fuel dilution and a significant barrier effect. Using a combination of aluminium phosphinate and melamine polyphosphate results in some charring and a dominant barrier effect. These effects are improved in the presence of zinc borate due to the formation of boron–aluminium phosphates instead of aluminium phosphates. KW - Flame retardancy KW - Polyamide 6,6 KW - Metal phosphinate KW - Melamine polyphosphate KW - Zinc borate PY - 2007 SN - 0141-3910 SN - 1873-2321 VL - 92 IS - 8 SP - 1528 EP - 1545 PB - Applied Science Publ. CY - London AN - OPUS4-15707 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Pawlowski, Kristin A1 - Schartel, Bernhard A1 - Fichera, Mario Augusto A1 - Jäger, Christian T1 - Flame retardancy mechanisms of bisphenol A bis(diphenyl phosphate) in combination with zinc borate in bisphenol A polycarbonate/Acrylonitrile-butadiene-styrene blends JF - Thermochimica Acta N2 - Bisphenol A polycarbonate/acrylonitrile–butadiene–styrene (PC/ABS) with and without bisphenol A bis(diphenyl phosphate) (BDP) and 5 wt.% zinc borate (Znb) were investigated. The pyrolysis was studied by thermogravimetry (TG), TG-FTIR and NMR, the fire behaviour with a cone calorimeter applying different heat fluxes, LOI and UL 94. Fire residues were examined with NMR. BDP affects the decomposition of PC/ABS and acts as a flame retardant in the gas and condensed phases. The addition of Znb results in an additional hydrolysis of PC. The fire behaviour is similar to PC/ABS, aside from a slightly increased LOI and a reduced peak heat release rate, both caused by borates improving the barrier properties of the char. In PC/ABS + BDP + Znb, the addition of Znb yields a borate network and amorphous phosphates. Znb also reacts with BDP to form alpha-zinc phosphate and borophosphates that suppress the original flame retardancy mechanisms of BDP. The inorganic–organic residue formed provides more effective flame retardancy, in particular at low irradiation in the cone calorimeter, and a clear synergy in LOI, whereas for more developed fires BDP + Znb become less effective than BDP in PC/ABS with respect to the total heat evolved. KW - Flame retardancy KW - PC/ABS KW - Aryl phosphate KW - Zinc borate KW - Flammability PY - 2010 DO - https://doi.org/10.1016/j.tca.2009.10.007 SN - 0040-6031 SN - 1872-762X VL - 498 IS - 1-2 SP - 92 EP - 99 PB - Elsevier CY - Amsterdam AN - OPUS4-20746 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Fichera, Mario Augusto A1 - Braun, Ulrike A1 - Schartel, Bernhard A1 - Sturm, Heinz A1 - Knoll, Uta A1 - Jäger, Christian T1 - Solid-state NMR investigations of the pyrolysis and thermo-oxidative decomposition products of a polystyrene/red phosphorus/magnesium hydroxide system JF - Journal of analytical and applied pyrolysis N2 - Thermal, thermo-oxidative and fire residues of high impact polystyrene/magnesium hydroxide/red phosphorus (HIPS/Mg(OH)2/Pr) are investigated by solid-state NMR and compared with the results for the binary subsystem Mg(OH)2/Pr. The influences of oxygen, nitrogen and temperature are discussed. For a thermal decomposition and pyrolysis during combustion, the main pyrolysis of HIPS takes place while the remaining residue is a rather intact polymer, with a major share of the embedded Pr still present. Subsequently, mainly amorphous phosphates and a slight amount of crystalline Mg3(PO4)2 and Mg2P2O7 are formed at the highest temperatures. Only with increasing mass loss does the remaining polystyrene structure decompose and graphitic structures occur. The influence of oxygen on the decomposition mechanism is most obvious for the binary system Mg(OH)2/Pr. Pr vanishes more rapidly and crystalline, oxygen-rich magnesium phosphates are formed. In HIPS/Mg(OH)2/Pr systems the polymer acts as a barrier to reaction by the embedded particles, so that major characteristics of an anaerobic decomposition are found. Significant amounts of phosphorus are retained in the condensed phase through a reaction of Pr with Mg(OH)2 to mostly amorphous phosphates. This formation of amorphous inorganic magnesium phosphates can act as an additional physical barrier. This study outlines some advanced approaches for controlling the condensed-phase mechanisms of phosphorus and underlines that solid-state NMR is a most powerful tool for investigating the organic and inorganic residues. KW - HIPS KW - Red phosphorus KW - Magnesium hydroxide KW - Solid-state NMR KW - Flame retarded polymers PY - 2007 SN - 0165-2370 SN - 1873-250X VL - 78 IS - 2 SP - 378 EP - 386 PB - Elsevier CY - Amsterdam AN - OPUS4-14517 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER -