Biochemical and molecular characterization of a thermostable chitosanase produced by the strain Paenibacillus sp. 1794 newly isolated from compost.

Chitosan raises a great interest among biotechnologists due to its potential for applications in biomedical or environmental fields. Enzymatic hydrolysis of chitosan is a recognized method allowing control of its molecular size, making possible its optimization for a given application. During the industrial hydrolysis process of chitosan, viscosity is a major problem; which can be circumvented by raising the temperature of the chitosan solution.

Metabolism and permeability of curcumin in cultured Caco-2 cells.

Scope: Curcumin (CUR) and its major metabolite hexahydro-CUR were studied in Caco-2 cells and in the Caco-2 Millicell® system in vitro to simulate their in vivo intestinal metabolism and absorption in humans.

Methods And Results: Analysis of the incubation medium and cell lysate showed that Caco-2 cells reduce CUR to hexahydro-CUR and octahydro-CUR, and conjugate CUR and its reductive metabolites with glucuronic acid and sulfate. Using the Caco-2 Millicell® system, an efficient transfer of the conjugates into the basolateral, but not the apical, compartment was observed after apical administration.

Real-time ESI-MS of enzymatic conversion: impact of organic solvents and multiplexing.

Different enzymatic assays were characterized systematically by real-time electrospray ionization mass spectrometry (ESI-MS) in the presence of organic solvents as well as in multiplex approaches and in a combination of both. Typically, biological enzymatic reactions are studied in aqueous solutions, since most enzymes show their full activity solely in aqueous solutions. However, in recent years, the use of organic solvents in combination with enzymatic reactions has gained increasing interest due to biotechnological advantages in chemical synthesis, development of online coupled setups screening for enzyme regulatory compounds, advantages regarding mass spectrometric detection and others.

Functional proteomics: application of mass spectrometry to the study of enzymology in complex mixtures.

This review covers recent developments in mass spectrometry-based applications dealing with functional proteomics with special emphasis on enzymology. The introduction of mass spectrometry into this research field has led to an enormous increase in knowledge in recent years. A major challenge is the identification of "biologically active substances" in complex mixtures.