[Technics of inactivating/removing medical chitosan pathogen].
OBJECTIVE
To verify the technics of inactivating/removing pathogens in medical chitosan derived from shrimp shell.


METHODS
Possible pathogen species were included according to the raw material of shrimp shell used in production, then bacillus cereus, porcine parvovirus (PPV) and pseudorabies virus (PRV) were selected as indicator pathogens. Pathogen solution was prepared in accordance with Technical Standard for Disinfection. The processing procedure of medical chitosan was analyzed to determine whether the alkalization of chitin and the filter sterilization of chitosan were capable of inactivating/removing pathogens and their efficiencies were tested.


RESULTS
Bacillus cereus was removed by 8184 cfu/mL after alkalization and 30818 cfu/mL after filter sterilization. The average logarithm inactivation value (LIV) of PPV and PRV after alkalization were equal to or above 4.76 logTCID50/0.1 mL and 6.67 logTCID50/0.1 mL, respectively, and their average LIV after filter sterilization were 2.25 logTCID50/0.1 mL and 3.04 logTCID50/0.1 mL. The alkalization of chitin inactivated/removed indicator pathogens effectively, while the filter sterilization of chitosan removed bacterial effectually but could not inactivate viruses completely.


CONCLUSIONS
The alkalization of chitin can be used as the technics of inactivating/removing pathogens during the preparation process of medical chitosan to guarantee the safety of the product.
Jiang
Lixia
L
Shanghai Qisheng Institute of Biomaterial and Technology, Shanghai, 201106, P.R. China. lixiajiang18@hotmail.com
Gu
Qisheng
Q
Li
Jian
J
D001409:Bacillus cereus / Q000302:isolation & purification; D048271:Chitosan; D013242:Sterilization / Q000379:methods*
D048271:Chitosan