These three experiments showed that GC/MS was better suited to monitoring samples containing large numbers of VOCs at high concentrations. In all other applications, SIFT-MS proved simpler to use, was linear with concentration over a much wider concentration range than GC/MS and provided faster results.

Consolidated bioprocessing (CBP) is a potential breakthrough technology for reducing costs of biochemical production from lignocellulosic biomass. Production of cellulase enzymes, saccharification of lignocellulose, and conversion of the resulting sugars into a chemical of interest occur simultaneously within a single bioreactor. In this study, synthetic fungal consortia composed of the cellulolytic fungus Trichoderma reesei and the production specialist Rhizopus delemar demonstrated conversion of microcrystalline cellulose (MCC) and alkaline pre-treated corn stover (CS) to fumaric acid in a fully consolidated manner without addition of cellulase enzymes or expensive supplements such as yeast extract. A titer of 6.87 g/L of fumaric acid, representing 0.17 w/w yield, were produced from 40 g/L MCC with a productivity of 31.8 mg/L/hr. In addition, lactic acid was produced from MCC using a fungal consortium with Rhizopus oryzae as the production specialist. These results are proof-of-concept demonstration of engineering synthetic microbial consortia for CBP production of naturally occurring biomolecules.

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Preparations of nucleic acids obtained by extraction of mouse liver, HeLa cells and cell fractions with phenol and deoxycholate have been characterized with regard to the differential solubility of ribonucleic acid and deoxyribonucleic acid in ethanol, density-gradient centrifugation and the presence of high-molecular-weight contaminants. Ribonucleic acid obtained by this method is less soluble than deoxyribonucleic acid. It was precipitable with 20 % ethanol, nearly free of deoxyribonucleic acid, but containing 4-5 times its weight of polysaccharide which is not removed by repeated fractional precipitation nor entirely by ~-amylase (EC 3.2.1.1) digestion, but is removed by density-gradient centrifugation. Deoxyribonucleic acid could be subsequently precipitated with 50 % ethanol free of ribonucleic acid but contaminated with polysaccharide. The buoyant density of the latter is identical with deoxyribonucleic acid and they are not separated by density-gradient centrifugation. The contaminating polysaccharide appears to be a single entity, the fl-subunit of glycogen granules. Its isolation and some of its properties are described. Its effect upon the properties of the nucleic acids is discussed.

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