title: Hurdle Effect of Antimicrobial Activity Achieved by Time Differential Releasing of Nisin and Chitosan Hydrolysates from Bacterial Cellulose.
abstract: We investigated the combined antimicrobial effect of nisin and chitosan hydrolysates (CHs) by regulating the antimicrobial reaction order of substances due to differential releasing rate from hydroxypropylmethylcellulose-modified bacterial cellulose (HBC). The minimum inhibitory concentration of nisin against Staphylococcus aureus and that of CHs against Escherichia coli were 6 IU and 200 μg/mL, respectively. Hurdle and additive effects in antimicrobial tests were observed when nisin was used 6 h before CH treatment against S. aureus; similar effects were observed when CH was used before nisin treatment against E. coli. Simultaneously combined treatment of nisin and CHs exhibited the low antimicrobial effect. HBC was then selected as the carrier for the controlled release of nisin and CHs. A 90% inhibition in the growth of S. aureus and E. coli was achieved when 30 IU-nisin-containing HBC and 62.5 μg/mL-CH-containing HBC were used simultaneously. The controlled release of nisin and CHs by using HBC minimized the interaction between nisin and CHs as well as increased the number of microbial targets.
authors.affiliation: Dept. of Food Science, National Ilan Univ, 1 Sec. 1, Shen Nung Rd., Ilan city, Taiwan, R.O.C.
authors.forename: Hui-Ling
authors.initials: HL
authors.lastname: Hsiao
authors.affiliation: Dept. of Food Science, National Ilan Univ, 1 Sec. 1, Shen Nung Rd., Ilan city, Taiwan, R.O.C.
authors.forename: Shih-Bin
authors.initials: SB
authors.lastname: Lin
authors.affiliation: Dept. of Food Science, National Ilan Univ, 1 Sec. 1, Shen Nung Rd., Ilan city, Taiwan, R.O.C.
authors.forename: Li-Chen
authors.initials: LC
authors.lastname: Chen
authors.affiliation: Dept. of Food Science, National Ilan Univ, 1 Sec. 1, Shen Nung Rd., Ilan city, Taiwan, R.O.C.
authors.forename: Hui-Huang
authors.initials: HH
authors.lastname: Chen
mesh_terms: D000890:Anti-Infective Agents / Q000494:pharmacology*; D002482:Cellulose / Q000737:chemistry*; D048271:Chitosan / Q000494:pharmacology*; D004926:Escherichia coli / Q000187:drug effects* / Q000254:growth & development; D005516:Food Microbiology; D018857:Food Packaging / Q000379:methods*; D005519:Food Preservation / Q000379:methods; D006801:Humans; D065347:Hypromellose Derivatives; D008826:Microbial Sensitivity Tests; D009561:Nisin / Q000494:pharmacology*; D013211:Staphylococcus aureus / Q000187:drug effects* / Q000254:growth & development
chemical_list: D000890:Anti-Infective Agents; D009561:Nisin; D065347:Hypromellose Derivatives; D002482:Cellulose; D048271:Chitosan
keywords: antimicrobial; bacterial cellulose; chitosan; hurdle; nisin