Purification And Characterization Of Porcine Lactoferrin

Lactoferrin has many kinds of biological activities, such as antibiosis, Anti-virus, Anti-fungus, Anti-parasite, Anti-tumor, Anti-oxidation, immune adjustment activity, effection intestinal bacterium groups, regulative gene expression, promote iron absorption. Moreover, Lf also has many other physiological actions, including platelet conjugation, promote wound healing, toxin conjugation, promote zooblast growth, et al. Lf and Lfcin can be a effective iron food additive, feed additive, immunity adjustment additive, gigestant, oxidation inhibitor, antiseptic and prophylaxis and treatment and so on. Its biological activities and application become a hot topic of research currently. Human lactoferrin and bovine lactoferrin Studies thoroughly, in aspect of purification, structure and biological characteristics, but porcine lactoferrin studies comparatively little. This paper has conducted the preliminary study to the Lf separation purification and the biology function.1 Porcine lactoferrin was isolated by CM Sephadex C-25 from defatted colostrum, using 0.05mol/L PBS (pH7.4) with 1mol/L and 5mol/L NaCl.2 Using the minimum inhibitory concentration studied Lf antibacterial activity. The results indicated that, pLf and bLf all have stronger bacteriostasis to the G~+ bacterium and the G~- bacterium. BLf MIC to staphylococcus aureus is 1000μg/mL; To escherichia coli, salmonella enteritidis, pasteurella multocida is 1250μg/mL; to bacillus subtilis is 1500μg/mL. PLf MIC to staphylococcus aureus is 1250μg/mL; to escherichia coli, salmonella enteritidis, pasteurella multocida is 1500μg/mL; to bacillus subtilis is 1750μg/mL. The experiment indicates that Lf's antibacterial activity to the G~+ bacterium is stranger than to the G- bacterium. BLf is a bit stronger than the pLf bacteriostat activity.3 Using the minimum inhibitory concentration studied Lf antibacterial activity. BLf,pLf and LfcinP have the same activeness to the identical serotype different drug resistance or the same serotype E coli, the MIC respectively be 1250μg/mL, 1500μg/mL and 100μg/mL. BLf, pLf and LfcinP have no obvious relations with the drug resistance of E coli.4 Experiment studied the influence of different carbonhydrate, nitrogen and electrolyte ionic strength on the inhibitoy activity of pLf. The results indicated that, Lf's inhibitoy activity was not affected by carbonhydrate (Glucose, Sucrose, Maltose, Lactose and starch) and nitrogen (BSA, Urea and Ammonium Sulfate) . Electrolyte ionic strength (25-150mmol/L NaCl or KCl,1.25-10mmol/L CaCl2 or MgCl2) had significantly effect Lf's inhibitoy activity.5 The best of protease hydrolysis conditions were: substrate concentration was 5%, enzyme and substrate concentration proportion was 1/30, hydrolisis time was 60min.6 Using the minimum inhibitory concentration studied LfcinP's antibacterial activity. The results indicated that, LfcinP MIC to staphylococcus aureus is 50μg/mL, activity enhanced 25 times; To escherichia coli, salmonella enteritidis and pasteurella multocida is 100μg/mL, enhanced 15 times; To bacillus subtilis is 100μg/mL, enhanced 17.5 times. The antibacterial activity of LfcinP is stronger 15-25 times than pLf.