23 research outputs found
Lactoferrin in plasma measured by an ELISA technique: Evidence that plasma lactoferrin is an indicator of neutrophil turnover and bone marrow activity in acute leukaemia
Amino acid sequence, location and phylogenetic aspects of the glycopeptides of human lactotransferrin
Enzymic synthesis of steroid sulphates XVII. On the structure of bovine estrogen sulphotransferase
Improved RP-HPLC method for determination of bovine lactoferrin and its proteolytic degradation in simulated gastrointestinal fluids
The objective of this study was to qualitatively and quantitatively evaluate bovine lactoferrin (bLf) and its stability using a rapid RP-HPLC method. bLf could be rapidly detected within 20 min and quantitated at levels down to 5mg/mL, and the equation of linearity was y = 86.10x + 178.31 with the correlation coefficient (r2) 0.9997. Quantitative data
obtained in the present study proved the improved RP-HPLC method to be a sensitive and accurate analytical tool for bLf determination. The proteolytic cleavage of bLf in simulated human gastrointestinal fluids was further analyzed by RP-HPLC, and found to follow pseudo-first-order kinetics. The typical equation obtained by pepsin was log10 [At]/[A0] = 0.03x (r2 = 0.85), and log10 [At]/[A0] = 0.01x (r2 = 0.81) for trypsin and chymotrypsin combination. Pepsinolysis of bLf in simulated
gastric fluid was relatively fast with the half-life t1/2 23.1 min. The digestion of bLf in simulated intestinal fluid was slower with
about a 3-fold increase in half-life (69.3 min). After the complete proteolysis of bLf, small cleaved peptide fragments were
fully separated and identified by RP-HPLC. The proteolytic study indicated that this validated RP-HPLC was able to evaluate
bLf stability though monitoring the derivatization products