Effect of intramammary infusion of chitosan hydrogels at drying-off on bovine mammary gland involution.

The transition from lactation to the dry period in dairy cows is a period of high risk for acquiring new intramammary infections. This risk is reduced when the involution of the mammary gland is completed. Accordingly, approaches that speed up the involution process after drying-off could reduce the incidence of mastitis.

Biocatalysis of immobilized chlorophyllase in a ternary micellar system.

The immobilization of chlorophyllase was optimized by physical adsorption on various inorganic supports, including alumina, celite, Dowex-1-chloride, glass beads and silica gel. The enzyme was also immobilized in different media, including water, Tris-HCl buffer solution and a ternary micellar system containing Tris-HCl buffer solution, hexane and surfactant. The highest immobilization efficiency (84.

Characterization of hydroperoxides and carbonyl compounds obtained by lipoxygenase extracts of selected microorganisms.

Partially purified lipoxygenase (LOX) extracts were obtained from Fusarium proliferatum, Fusarium oxysporum, Chlorella pyrenoidosa, and Saccharomyces cerevisiae; the enzymatic extract of F. proliferatum showed the highest LOX activity while those of F. oxysporum and S.

Partial purification and some properties of lipoxygenase from Saccharomyces cerevisiae.

A partially purified lipoxygenase extract was obtained from the yeast Saccharomyces cerevisiae by precipitation with solid (NH4)SO4 at 20% to 80% saturation. The enzyme had two pH optima, at pH 8.0 and 10.