Division of Food Science and Biotechnology, Faculty of Agriculture, Kyushu University, 744 Motooka, Nishi-ku, Fukuoka 819-0395, Japan; Department of Food Technology, College of Agriculture, Can Tho University, Campus II, 3/2 Street, Ninh Kieu District, Can Tho, Viet Nam.
Department of Food Technology, College of Agriculture, Can Tho University, Campus II, 3/2 Street, Ninh Kieu District, Can Tho, Viet Nam.
J Food Prot. 2023 Mar;86(3):100044. doi: 10.1016/j.jfp.2023.100044. Epub 2023 Jan 23.
Biofilm formation of Listeria monocytogenes in food processing environments cause potential source of cross-contamination to foodstuffs; hence, the control of biofilm is currently addressed to find effective solutions for preventing biofilm formation or eliminating the established one. Forty-five strains of Listeria monocytogenes isolated from Pangasius fish-processing plants were studied for their capability to form a biofilm on 96-well microtiter plate by using the conventional crystal violet staining. Additionally, the inhibitory effect of biofilm formation by food additives including monascus pigment and ε-polylysine was examined. The average OD value showing biofilm mass of all 45 strains L. monocytogenes increased with an increasing temperature and time (p < 0.05). Monascus pigment and ε-polylysine significantly decreased biofilm formation by 80 ± 5.5% and 20 ± 5.9%, respectively, at the tested concentration (p < 0.05) Further, the effects of lysozyme (0.1 mg/mL) alone or in combination with slightly acidic hypochlorous water (SAHW) with 40 mg/L available chlorine or sodium hypochlorite (NaOCl) with 100 mg/L available chlorine against 7-d established biofilm of L. monocytogenes were investigated. The results indicated that slightly acidic hypochlorous water alone exhibited significant antibacterial activity (p < 0.05), decreasing the viable count by 5.2 ± 0.5 log CFU/mL. It seems that sequential treatment of lysozyme and SAHW showed an additional efficacy against biofilm of L. monocytogenes on polystyrene plate surface, reducing 70% of biomass of biofilm and 7.6 ± 0.3 log of biofilm viable cells (p < 0.05). Additionally, SAHW exhibited greater bactericidal activity against viable biofilm cells than NaOCl did. This result reveals that SAHW is a promising disinfectant agent against L. monocytogenes and the potential alternative to NaOCl in practice.
在食品加工环境中，李斯特菌的生物膜形成是潜在的食源交叉污染源；因此，目前的生物膜控制旨在寻找有效解决方案，以防止生物膜形成或消除已建立的生物膜。本研究从 Pangasius 鱼加工厂分离出 45 株李斯特菌，通过使用传统的结晶紫染色法，在 96 孔微量滴定板上研究其形成生物膜的能力。此外，还研究了食品添加剂（红曲色素和ε-聚赖氨酸）对生物膜形成的抑制作用。所有 45 株李斯特菌的平均 OD 值（表示生物膜质量）随温度和时间的增加而增加（p<0.05）。红曲色素和ε-聚赖氨酸分别在测试浓度下显著降低生物膜形成 80±5.5%和 20±5.9%（p<0.05）。此外，还研究了溶菌酶（0.1mg/mL）单独或与 40mg/L 有效氯的微酸性次氯酸水（SAHW）或 100mg/L 有效氯的次氯酸钠（NaOCl）联合使用对 7 天建立的李斯特菌生物膜的影响。结果表明，单独使用微酸性次氯酸水具有显著的抗菌活性（p<0.05），可使活菌数减少 5.2±0.5log CFU/mL。似乎溶菌酶和 SAHW 的序贯处理对聚苯乙烯板表面的李斯特菌生物膜表现出额外的功效，减少生物膜生物量的 70%和生物膜活菌的 7.6±0.3log（p<0.05）。此外，SAHW 对活菌生物膜细胞的杀菌活性大于 NaOCl。该结果表明，SAHW 是李斯特菌的一种有前途的消毒剂，是实践中替代 NaOCl 的潜在选择。
