MIRANDA Maria Victoria
congresos y reuniones científicas
Optimization of bovine lactoferrin enzymatic hydrolysis for lactoferricin B isolation.
NICOLÀS URTASUN; MARIA VICTORIA MIRANDA; OSVALDO CASCONE; FEDERICO WOLMAN
Congreso; SAIB; 2009
Antimicrobial peptides, particularly cationic peptides have received increasing attention as new pharmaceutical products. Bovine lactoferricin is a small positively-charged fragment of the larger protein lactoferrin (Lf), which is found in cow`s milk and whey, a cheese manufacture subproduct. The aim of this work is to optimize the conditions for pepsin digestion of Lf to obtain a high yield of lactoferricin for its further purification by affinity membrane chromatography. Preliminary assays were performed in solution with standard bovine Lf. A 10 mg/ml Lf aqueous solution was adjusted to pH 1.3 or 3.0 and digested with 0,04 mg/ml porcine pepsin at 37 ºC for different periods, between 0 and 20 h. The reactions were stopped by heating at 80ºC for 15 min and the pH adjusted to 7.0 by addition of 1 M NaOH. Hydrolysates were tested for its antibacterial activity by using the susceptible strain Bacillus subtilis ATCC 6633. For the pH 3.0 digest, the results evidenced time dependence with the highest antimicrobial activity after 20 h incubation. For the pH 1.3 digest, the maximum antimicrobial activity appeared at 1 h and remained constant during the period studied. For hydrolysis of Lf adsorbed onto chromatographic matrix, the pH 3.0-based process is the best choice attended to the chemical stability of the support.