Meteorites contain prebiotic, bio-relevant organic compounds including amino acids. Their syntheses could result from diverse sources and mechanisms provide a window on the conditions materials present in early solar system. Here we constrain alanine’s synthetic history Murchison meteorite using site-specific 13C/12C measurements, reported relative to VPDB standard. The ?13CVPDB values of ?29 ±...

Modification of the Bücherer-Strecker amino acid synthesis facilitated the production of DL-[11C]tryptophan and DL-[11C]valine for clinical trials in patients with proven or suspected pancreatic disease. Examples of rectilinear scans and tomographic images of the pancreas are presented in this initial paper. Positron computed tomography was done with the ORTEC ECAT system. Rapid localization of...

This booklet consists of the addresses delivered at the opening of the new laboratory for biochemical research at McLean Hospital. Cecil K. Drinker reviews the history of research at McLean Hospital. Jordi Foich surveys biochemical research in psychiatry with emphasis on his own contributions to the chemical constitution of the brain. The record of reasearch at the Psychiatric Service of the Ma...

Following his seminal work in 1953, Stanley Miller conducted an experiment in 1958 to study the polymerization of amino acids under simulated early Earth conditions. In the experiment, Miller sparked a gas mixture of CH4, NH3, and H2O, while intermittently adding the plausible prebiotic condensing reagent cyanamide. For unknown reasons, an analysis of the samples was not reported. We analyzed t...

After vacuum distillation and liquid-liquid extraction, the volatile fractions of dark chocolates were analyzed by gas chromatography-olfactometry and gas chromatography-mass spectrometry. Aroma extract dilution analysis revealed the presence of 33 potent odorants in the neutral/basic fraction. Three of these had a strong chocolate flavor: 2-methylpropanal, 2-methylbutanal, and 3-methylbutanal....

Aims. Methyl isocyanate (CH 3 NCO) and glycolonitrile (HOCH 2 CN) are isomers prebiotic molecules that involved in the formation of peptide structures nucleobase adenine, respectively. These two species investigated to study interstellar chemistry cyanides (CN) isocyanates (NCO) gain insight into reservoir molecules. Methods. ALMA observations intermediate-mass Class 0 protostar Serpens SMM1-a ...

This work attempts to measure the importance of methional and phenylacetaldehyde on the flavor stability of beer, as direct participants or as indicators of aroma deterioration. A trained sensory panel identified the most important descriptors related to the typical aroma of aged beer: "malty", "honey-like", "cooked potato", and "metallic". By GC-olfactometry analysis, six aromatic zones relate...

Wine models with or without a dearomatised and lyophilized red wine extract containing young aroma base (control) plus one vector several compounds (unsaturated-aldehydes, saturated-aldehydes, benzaldehyde, isoamyl-alcohol, methoxypyrazines (Z)-1,5-octadien-3-one) were prepared. Models spiked increasing amounts of acetaldehyde whose headspace concentrations controlled. Odour nasal chemesthesic ...