Biomedical subjects

R L Hendrickson

Publications and source records attributed to R L Hendrickson.

3 recordsLinked to original sources

PubMed1996

Enzyme conversion of lignocellulosic plant materials for resource recovery in a Controlled Ecological Life Support System.

A large amount of inedible plant material composed primarily of the carbohydrate materials cellulose, hemicellulose, and lignin is generated as a result of plant growth in a Controlled Ecological Life-Support System (CELSS). Cellulose is a linear homopolymer of glucose, which when properly processed will yield glucose, a valuable sugar because it can be added directly to human diets. Hemicellulose is a heteropolymer of hexoses and pentoses that can be treated to give a sugar mixture that is potentially a valuable fermentable carbon source. Such fermentations yield desirable supplements to the edible products from hydroponically-grown plants such as rapeseed, soybean, cowpea, or rice. Lignin is a three-dimensionally branched aromatic polymer, composed of phenyl propane units, which is susceptible to bioconversion through the growth of the white rot fungus, Pluerotus ostreatus. Processing conditions, that include both a hot water pretreatment and fungal growth and that lead to the facile conversion of plant polysaccharides to glucose, are presented.

Biodegradation, Environmental↗

PubMed1995

Simultaneous concentration and purification through gradient deformation chromatography.

Mobile-phase additives, commonly used to modulate absorbate retention in gradient elution chromatography, are usually assumed to be either linearly retained or unretained. Previous theoretical work from our laboratory has shown that these modulators, such as salts in ion-exchange and hydrophobic interaction chromatography and organic modifiers in reversed-phase chromatography, can absorb nonlinearly, giving rise to gradient deformation. Consequently, adsorbate peaks that elute in the vicinity of the head of the deformed gradient may exhibit unusual shapes, form shoulders, and/or be concentrated. These effects for a reversed-phase sorbent with aqueous acetonitrile (ACN) as the modulator are verified experimentally. Gradient deformation is demonstrated experimentally and agrees with simulations based on ACN isotherm parameters that are independently determined from batch equilibrium studies using the layer model. Unusual absorbate peak shapes were found experimentally for single-component injections of phenylalanine, similar to those calculated by the simulations. A binary mixture of tryptophan and phenylalanine is used to demonstrate simultaneous concentration and separation, again in agreement with simulations. The possibility of gradient deformation in ion-exchange and hydrophobic interaction chromatography is discussed.

Acetonitriles↗

PubMed1976

Effects of treatment of whole fat soybeans or soy flour with formaldehyde to protect the polyunsaturated fatty acids from biohydrogenation in the rumen.

Full-fat, ground soy flour (GSF) was treated with 37% formaldehyde (HCHO) and evaluated by in vitro and in vivo criteria to determine the protection afforded linoleic acid against ruminal biohydrogenation when the materials described above were fed as a protein supplement to rations for growing lambs. The supplements compared were soybean meal (SBM), uked for 2 hours. Organoleptic evaluations were conducted to determine if any flavor differences in meat from lambs fed these supplements could be detected. Excellent protection of linoleic acid, the major polyunsaturated fatty acid in soybeans, was noted both in vitro and in vivo. Rump, shoulder, kidney knob and omental fat depots of lambs fed the HCHO treated GSF ration had significantly more linoleic acid than lambs fed untreated GSF while lambs fed untreated GSF had significantly, more linoleic acid in their fat depots than lambs fed SBM. Linoleic acid content of intramuscular (loin) fat from lambs fed HCHO treated GSF was not significantly different from lambs fed untreated GSF, but lambs fed untreated GSF had significantly more loin linoleic acid than lambs fed SBM. No significant differences were noted in daily feed intake, feed efficiency or average daily gain for lambs fed growing-finishing rations containing any of the products tested as the protein supplement. A taste panel could not detect any differences in flavor of ground loin among any of the treatments.

Adipose Tissue↗