紫外线A联合异硫氰酸盐杀菌效果评价

  目的  研究紫外线A发光二极管（UVA-LED）与植物化学物烯丙基异硫氰酸盐（AITC）联合对两种致腹泻病原菌的杀菌效果。  方法  以肠致病性大肠杆菌和副溶血性弧菌两种致腹泻病原菌为受试对象，采用不同浓度的烯丙基异硫氰酸盐与UVA_{365 nm}-LED结合进行二因素3 × 2析因设计杀菌实验，以菌落形成单位（CFU）计数细菌存活量并计算各自存活率对数值，然后进行析因设计的方差分析，并做交互效应图。  结果  单独AITC的杀菌效果随着浓度的增高而逐渐增强（P < 0.05），而且UVA_{365 nm} -LED与AITC联合对2种致病菌的效应差异都具有统计学意义（P < 0.05）。
UVA-LED和1 mg/mL AITC联用时副溶血性弧菌的存活率降低至 – 6.15 lg。  结论  UVA-LED与烯丙基异硫氰酸盐的联用，对肠致病性大肠杆菌和副溶血弧菌的杀菌效果都存在显著的协同作用。

Enhanced germicidal effects of pulsed UV-LED irradiation on biofilms

  Objective  To study bactericidal effect of ultraviolet A – light emitting diode (UVA-LED) irradiation combined with phytochemical of allyl isothiocyanate (AITC) on two diarrhea-causing pathogens.   Methods  Two diarrhea-causing pathogenic bacteria, enteropathogenic Escherichia coli (ETEC) and Vibrio parahaemolyticus (VP), were used as the subjects. Bactericidal experiments in 3 × 2 factorial design were performed with the combined treatment of different concentrations of AITC and UVA_{365 nm}-LED irradiation; and the bacteria survival was assessed with colony form unit (CFU) and logarithm value of survival rate was calculated. The interactive effect of AITC and UVA_{365 nm}-LED irradiation was evaluated with analysis of variance for factorial design and illustrated with schematic diagram.   Results  The bactericidal effect of AITC alone was gradually increased with the increment of concentration (P < 0.05).
The effect of the combination of UVA-LED irradiation with AITC on the two pathogenic bacteria were statistically significant (P < 0.05). When UVA_{365 nm} irradiation was combined with 1 mg/ml AITC, the survive ratio of Vibrio parahaemolyticus was even reduced to – 6.15 lg.   Conclusion  Synergistic bactericidal effect exists for combined treatment of UVA-LED irradiation and AITC on ETEC and VP.