An efficient enzymatic process was developed to produce optically pure D-phenylalanine through asymmetric resolution of the racemic DL-phenylalanine using immobilized phenylalanine ammonia-lyase (RgPAL) from Rhodotorula glutinis JN-1. RgPAL was immobilized on a modified mesoporous silica support (MCM-41-NH-GA). The resulting MCM-41-NH-GA-RgPAL showed high activity and stability. The resolution ...

There is considerable experimental evidence in support of the view that, in solution, the state of molecular dispersion of insulin is dependent on the net charge of the protein (10, 6, 8). In these investigations, alterations of the net positive charge were obtained by varying the pH of the solutions, with due consideration of the effect of the specific binding affinity of the protein for anion...

Leishmania amastigotes parasitize almost exclusively the mononuclear phagocytes of mammals. The organisms survive and multiply within acidified vacuoles (parasitophorous vacuoles; p.v.) akin to phagolysosomes. Certain amino acid esters are known to accumulate in and disrupt lysosomes. We postulated that, since Leishmania possess lysosome-like organelles, they may be susceptible to the potential...

two modified methods for assaying sodium diclofenac were developed by gc and hplc. diclofenac was converted into methyl ester derivative by methyl iodide in acetone. the ester was extract and subjected to glc with flame ionization detector. %5 se-30/chrom w-hp (80-100 mesh) was used as a column in gc. for reversed phase hplc, the mobile phase was methanol and water (55-45). the separation was p...

OBJECTIVE To produce models to estimate the impact of introducing clinical networks and the 2001 BAPM standards to the delivery of neonatal care. DESIGN Prospective observational study using a geographically defined population and data collected by questionnaire on staffing levels and cot availability. SETTING Trent Health Region UK. SUBJECTS All infants born to Trent resident mothers at ...

Conflicting reports exist concerning the effect aspartame (APM, l-aspartyl-l-phenylalanine methyl ester) has upon brain biogenic amines. In the following study, in vivo voltammetry was utilized to measure evoked extracellular dopamine (DA) levels in the striatum of rats in order to assess APM's effect. Time-course experiments revealed a significant decline in evoked extracellular DA levels with...

The effects of the chemical constitution and structure of the substituent on the excited state dynamics of several model fluorescent pyrene-labelled molecules of biophysical interest have been examined. Nine new 1-substituted pyrenyl compounds, Py-NH-CO-C2H5, Py-NH-CO-Leu-Boc, Py-CH2-NH-CO-C2H5, Py-CH2-NH-CO-Leu-Boc, Py-CO-NH-C3H7, Py-CO-NH-Leu-OMe, Py-CH2-CO-NH-C3H7, Py-CH2-CO-NH-Leu-OMe and P...

We have previously indicated that three single mutations (Leu144-->Ser, Asp150-->Glu, and Ile168-->Ala) in the site-directed mutagenesis of thermolysin increase the activity and two single (Ser53-->Asp and Leu155-->Ala) and one triple (Gly8-->Cys/Asn60-->Cys/Ser65-->Pro) mutations increase the stability. In the present study, aiming to generate highly active and stable thermolysin variants, we ...