摘要
食源性致病菌是人类健康的主要威胁之一。本研究旨在探讨壳聚糖(chitosan,Chi)协同姜黄素(curcumin,Cur)介导的光动力处理(photodynamic treatment,PDT)对致病菌的灭活效果。在确定Chi的最低抗菌剂量后,比较PDT和Chi-PDT的杀菌效果,进而评价Cur浓度和光照时间对Chi-PDT灭活金黄色葡萄球菌(Staphylococcus aureus)、蜡样芽孢杆菌(Bacillus cereus)、大肠杆菌(Escherichia coli O157:H7)和沙门氏菌(Salmonella Typhimurium)的影响。同时,探究Chi与PDT的协同作用机制以及Chi-PDT对混合致病菌的灭活作用、对圣女果表面Salmonella的灭活作用和对圣女果品质的影响。结果表明:Chi可以通过增强细菌与Cur的相互作用从而增强PDT灭活效果。Chi-PDT的灭菌效果具有Cur浓度和光照时间依赖性,0.05%(质量分数,下同)Chi结合15μmol/L Cur处理后光照20 min可分别使S.aureus和B.cereus的菌落总数减少7.90、7.60(lg(CFU/mL)),而对E.coli和Salmonella则分别需要0.05%Chi-100μmol/L Cur和0.05%Chi-25μmol/L Cur处理后光照20 min才能达到相似的抑菌效果。Chi-PDT处理可使4种混合菌的菌落总数减少6.00(lg(CFU/mL)),比PDT单独处理时的抑菌量高5.09(lg(CFU/mL)),表明无论是对于单一菌还是混合菌,Chi-PDT协同作用都比PDT单独处理具有更好的灭菌效果。Chi-PDT可使圣女果表面Salmonella的菌落总数减少1.62(lg(CFU/果)),Chi-Cur涂膜协同PDT处理在圣女果保藏期间显示出了较好的抑菌效果,且不影响其色泽、硬度和质量损失率。因此,Chi-Cur协同PDT处理是食品杀菌和果蔬保藏领域中颇具潜力的食品保鲜技术。
Foodborne pathogens are a major threat to human health.The aim of this study was to investigate the inactivating effect of chitosan(Chi)combined with photodynamic treatment(Chi-PDT)mediated by curcumin(Cur)on pathogens.After determining minimal inhibitory concentration of Chi,we compared the bactericidal effects of PDT and Chi-PDT,and evaluated the influence of curcumin concentration and illumination time on the inactivating effect of Chi-PDT against Staphylococcus aureus,Bacillus cereus,Escherichia coli and Salmonella Typhimurium.The mechanism for the synergistic bactericidal effect of Chi and PDT,the inactivating effect of Chi-PDT on pathogen cocktails and Salmonella on the surface of cherry tomatoes and the impact of Chi-PDT on the quality of cherry tomatoes were assessed.The results showed that chitosan could augment the inactivating effect of PDT by enhancing the interaction between bacteria and Cur.The sterilization effect of Chi-PDT was dependent on Cur concentration and illumination time.Moreover,20 min illumination after treatment with 0.05%chitosan combined with 15μmol/L curcumin reduced the counts of S.aureus and B.cereus by 7.90 and 7.60(lg(CFU/mL)),respectively.However,for E.coli and Salmonella,similar effects required treatment with 0.05%Chi plus 100μmol/L Cur and 0.05%Chi plus 25μmol/L Cur,respectively.Chi-PDT reduced the total count of the quaternary bacterial mixture by 6.00(lg(CFU/mL)),which was 5.09(lg(CFU/mL))higher than that with PDT alone.These results showed that Chi-PDT had a better bactericidal effect against both individual and mixed bacteria than PDT.The count of Salmonella on the surface of cherry tomatoes was reduced by 1.62(lg(CFU/fruit))by Chi-PDT.Chi-Cur coating combined with PDT treatment inhibited bacterial growth on cherry tomatoes during storage without affecting the color,firmness or mass loss.Thus,Chi-Cur coating combined with PDT treatment has great potential for application in the fields of food sterilization and fruit and vegetable preservation.
作者
蓝彩娟
陈洁怡
何雨薇
麻春阳
黄蕊
Nima AZARAKHSH
Tanushree GUPTA
吴希阳
LAN Caijuan;CHEN Jieyi;HE Yuwei;MA Chunyang;HUANG Rui;Nima AZARAKHSH;Tanushree GUPTA;WU Xiyang(College of Science&Engineering,Jinan University,Guangzhou 510632,China;Hopkirk Research Institute,Massey University,Palmerston North 4474,New Zealand)
出处
《食品科学》
EI
CAS
CSCD
北大核心
2023年第21期258-266,共9页
Food Science
基金
广东省国际科技合作基地-中国-新西兰食品安全与营养保障国际联合研究中心项目(2021A0505020016)
广东省重点领域研发计划项目(2019B020212004)。
关键词
光动力处理
致病菌
壳聚糖-姜黄素
圣女果
食品保鲜
photodynamic treatment
pathogens
chitosan-curcumin
cherry tomato
food preservation