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A new protease was isolated from the intestine of small red scorpionfish. After ammonium sulfate precipitation, the enzyme was purified to homogeneity by a two-step chromatography with 6.69% recovery and fivefold increase in specific activity. The molecular weight of the protease was about 24 kDa as estimated by size exclusion chromatography and sodium dodecyl sulfate-polyacrylamide gel electrophoresis. The enzyme optimum pH and temperature were pH 10.0 and 40°C, respectively. The protease was stable at temperatures below 40°C and over a broad pH range (8.0-11.0). The Km and Kcat values were 0.36 mmol L-1 and 1.61 s-1, respectively. Interestingly, the enzyme presented specificity for casein, egg albumin, bovine serum albumin, and gelatin with obtained degrees of hydrolysis ranging from 3.14% to 6.58%, after 2 h of hydrolysis. Moreover, gluten hydrolysate analysis confirmed protein hydrolysis and solubilization. These results suggested the potential use of the protease in the preparation of food protein hydrolysates with interesting properties. [ABSTRACT FROM AUTHOR]

Abstract: Three polysaccharide fractions (DDP1-1, DDP2-1 and DDP3-1) were successfully purified from the crude polysaccharide of Dendrobium denneanum by DEAE-Cellulose and Sephadex G-200 column chromatography. The average molecular weights (Mws) of these fractions were 51.5, 26.1 and 6.95kDa, respectively. Monosaccharide components analysis indicated that DDP1-1 and DDP2-1 were composed of arabinose, xylose, mannose, glucose and galactose in a molar ratio of 1.00:2.82:57.11:140.82:7.76 and 1.00:1.62:1.18:77.5:7.79. DDP3-1 was composed of arabinose, mannose, glucose and galactose in a molar ratio of 1.00:1.03:8.84:2.00. On the basis of antioxidant test in vitro, DDP2-1 exhibited the highest antioxidant ability among these samples. [Copyright &y& Elsevier]

The Wendler version of the Torgov-Ananchenko scheme of total steroid synthesis was shown to be applicable to the preparation of 6-oxaestra-1,3,5(10),8,14-pentaenes. Conditions for cyclodehydration of secosteroids thus obtained were found, which ensured isolation of the target compounds in a high yield without using chromatographic purification methods. [ABSTRACT FROM AUTHOR]

The results reported in the present paper and N-terminal sequence homologies established by other authors strongly support the assumption that the gastric protease previously called bovine pepsin I or bovine pepsin B belongs to the aspartate protease group and corresponds to gastricsin (or pepsin C) (EC 3.4.23.3) from other species. Bovine gastricsin was prepared from commercial extracts of adult bovine veils by a procedure involving DEAE-cellulose chromatography, gel filtration on Sephacryl S-200 and a further DEAE-cellulose chromatography. The preparation thus obtained was shown to be free of chymosin and bovine pepsin A by immunodiffusion, selective inactivation in urea and isoelectric focusing. Us molecular weight was estimated by gel filtration to be 32800. Bovine gastricsin displayed microheterogeneity on isoelectric focusing with pi values of the components ranging from 3.5 to 4.0. Chromatography of bovine gastricsin on hydroxyapatite separated three fractions, none of them being homogeneous by isoelectric focusing. Concanavalin-A—Sepharose 4B bound bovine gastricsin to some extent, but without any significant fractionation. Proteolytic activity could be detected directly on the isoelectric focusing gel for all the components of gastricsin and its fractions from hydroxyapatite and concanavalin-A—Sepharose 4B. Bovine gastricsin and its fractions from hydroxyapatite have similar amino acid compositions, different from those of bovine chymosin and pepsin A but obviously related to those of human, simian and porcine gastricsins. Bovine gastricsin which is inactivated by reaction with diazoacetyl-DL-norleucine methyl ester and with 1,2-epoxy-(p-nitrophenoxy)propane in a 1:1 and 1:2 stoichiometry, respectively, is able to hydrolyse a synthetic hexapeptide, Leu-Ser-Phe(NO2)-Nle-Ala-Leu-OMe, used as reference substrate for aspartate proteases, and exhibits a low activity towards N-acetyl-L-phenylalanyl-L-diiodotyrosine. Its specific clotting activity with χ-casein as substrate is only half of that of chymosin and pepsin A. [ABSTRACT FROM AUTHOR]

The article focuses on the use of Kromasil CelluCoat in the analysis and purification of chiral compounds. Kromasil CelluCoat refers to a silica based chiral stationary phases (CSP) coated with tris-carbamoyl cellulose as the chiral selector. The analysis involves a factor of selectivity that leads to enantiomer separation, which leads to the speed of separation.

The article present information about introduction of new polymeric reversed-phase columns, Amberchrom™ Profile™. These columns have been developed for the purification of peptides and oligonucleotides by reversed-phase chromatography. The columns have been able to achieve the purification target yield of eighty percent at more than ninety five percent purity in the purification of influenza peptide, that is used in the area of vaccine development..

Describes the use of the multiOPLC system, an Optimum Performance Laminar Chromatography system that incorporates the Flowing Eluent Wall Technology, to perform simultaneous semi-preparative scale separations of complex samples. Reagents and separation media; Instrumentation; Capability of the system to produce four independent channels on an unsegmented flat-bed column.

Demonstrates the utility of Atlantis dC[sub 18] columns via the separation and purification of three mixtures of polar compounds. Experimental conditions; Description of Atlantis dC[sub 18] reversed-phase columns; Retention and separation of the sulphonamides on the analytical column.

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