Biomedical subjects

Scott R Bean

Publications and source records attributed to Scott R Bean.

4 recordsLinked to original sources

PubMed2006

Physical and biochemical properties of maize hardness and extrudates of selected hybrids.

Protein and starch determinants of maize kernel hardness and extruded products were characterized to better define the role of endosperm texture during extrusion. Maize physical properties were correlated with total proteins and zein subclasses (p < 0.01). The extrusion process significantly altered protein solubility and increased protein fragmentation as measured by RP-HPLC and size exclusion chromatography. Harder grits and extrudates demonstrated higher amylose content, lower degree of starch damage, and fragmentation at different screw speeds than softer grits and extrudates. Differences in extrudate expansion ratio, water absorption index, water solubility index, oil absorption capacity, and breaking stress between harder and softer hybrids were related to protein aggregation and fragmentation as well as starch damage and fragmentation.

Amylose↗

PubMed2005

Capillary electrophoresis for monitoring dityrosine and 3-bromotyrosine synthesis.

Protein oxidation affects the structure of many amino acids. Variants of tyrosine are increasingly important in medical and food sciences. The synthesis of standards is essential for monitoring the disease state of patients with various illnesses and the quality of a number of food products. A method for monitoring standard synthesis of dityrosine and 3-bromotyrsoine from tyrosine using capillary electrophoresis (CE) is presented. Optimum separation was achieved using an isoelectric buffer consisting of 100mM iminodiacetic acid (IDA)+75 mM lauryl sulfobetaine (SB 3-12)+0.02% hydroxypropyl methylcellulose (HPMC) in a 27 cm x 75 microm capillary at 22 kV and 45 degrees C. Using these conditions the tyrosine adducts could be easily separated in less than 4 min. The resolution of the CE method was similar to HPLC separations, but analysis time was distinctly shorter.

Electrophoresis, Capillary↗

PubMed2004

Development of a quantitative high-performance liquid chromatography-photodiode array detection measurement system for phenolic acids.

A quantitative high-performance liquid chromatography-photodiode array detection method separating 16 phenolic acids was achieved. Six columns and several mobile phases were investigated. Resolution was achieved with a high-purity silica Phenomenex Luna C18 column (150 mm x 4.6 mm, 5 microm) and a binary gradient consisting of CH3OH-water (with 0.1% formic acid) and flow rate set at 0.7 ml/min. Acids were detected and quantitation performed at wavelength representing the lowest energy lambda(max) for individual acids. Extraction procedure from wine was optimized and yields ranged from 79 to 87% based on internal standard recovery. To confirm our quantitative results, identical samples were analyzed both in-house and by a collaborating laboratory. Correlation of two data sets generated linear regression equations that approached unity (0.93-0.98) and R2 values ranging from 0.990 to 0.999.

Calibration↗

PubMedDate not supplied

Capillary electrophoresis of cereal proteins: an overview.

Cereal grains are important both nutritionally and economically in virtually every country in the world. Cereal grains can be made into a wide range of human foods and are also important animal feed components. Although all of the biochemical components of cereal grains are important, cereal proteins play major functional, as well as nutritional, roles in foods. Cereal proteins are complex mixtures of proteins that are often difficult to solubilize and separate. Because of this, a wide range of analytical techniques have been used to separate and characterize cereal proteins. One of the new techniques used to separate these challenging proteins is high-performance capillary electrophoresis (HPCE). This review covers methods developed to separate cereal proteins by HPCE.

Complex Mixtures↗