【作者】 周辉；

【导师】 卢向阳；

【作者基本信息】 湖南农业大学 ， 生物化学与分子生物学， 2007， 硕士

【摘要】 【研究背景】过去人们大都使用合成防腐剂，一些合成的防腐剂长期使用有诱癌性、致畸性和易引起食物中毒等问题。随着社会的发展进步和人民生活水平的提高，对食品安全提出更高的要求，追求添加剂的天然、营养和功能化。鉴于此，寻求安全、高效的天然食品防腐剂成为食品科学、应用生物学的重要课题之一。【目的】探讨石香薷挥发油对食源菌的生长抑制能力；对冷却猪肉中腐败菌的生长抑制作用；初步研究石香薷挥发油及百里香酚的抗菌机理；并探讨石香薷挥发油微胶囊的制备工艺。【方法】利用杯碟法体外测定了石香薷挥发油及其主要成分对常见食源菌和冷却猪肉中腐败菌的抗菌能力；通过测定经石香薷挥发油及百里香酚作用后菌株的生长及氮源利用率、孢子萌发率，结合电镜观察探讨石香薷挥发油及其主要化学成分百里香酚的抑菌机理；采用喷雾干燥法制备石香薷挥发油微胶囊。【结果】1、石香薷挥发油对常见食源性细菌具有一定的抑制作用，其中对金黄色葡萄球菌、链球菌及沙门氏菌的抑制效果最好，对三种细菌的MIC、MBC均为0.3125mg／mL、0.625mg／mL。2、石香薷挥发油、百里香酚、香荆芥酚对常见食源性真菌均具有一定的抑制能力，而Nisin则对真菌的抑制作用较弱。3、从冷却猪肉中分离鉴定出微球菌、假单孢菌和葡萄球菌三类菌，石香薷挥发油对三类腐败菌均具有明显的抑制作用，对其MIC分别为0.3125、0.625、2.5mg／mL，MBC为0.625、1.25、5mg／mL。4、百里香酚、香荆芥酚及石香薷挥发油均能抑制金黄色葡萄球菌对氮源的利用能力。经过百里香酚处理后的金黄色葡萄球菌，其细胞膜局部出现空隙，发生明显的质壁分离，且细胞质发生局部的凝集。5、百里香酚能抑制黄曲霉孢子的萌发，处理后的孢子表面较平滑，具有凹陷现象，而菌丝的表面则变得光滑、扭曲欲折，分支少。6、喷雾干燥法制备石香薷挥发油微胶囊的主要工艺条件为：石香薷挥发油与壁材A的比例为1mL：6g，乳化剂用量为0.05％，总固形物浓度为30g／L。【结论】1、石香薷挥发油及其主要化学成分对常见食源菌均有一定的抑制生长作用。2、石香薷挥发油及其主要化学成分对冷却猪肉中腐败菌具有一定的抑制生长作用。3、石香薷挥发油及其主要成分可能通过抑制菌体的生长增殖、抑制氮源利用及抑制孢子萌发等多种途径来实现抑制生长作用。4、喷雾干燥法制备石香薷挥发油微胶囊工艺简单，便于工业化。更多还原

【Abstract】 [Background] In the past, people mostly used the synthesis antiseptics, butsome synthesis antiseptics may induce the cancer, abnormity and foodpoisoning. Along with the improvement of society and enhancement of living standardof people, set a higher request to the safe, natural and nutritional additives. In viewof the fact that, seeking the highly effective and natural food antiseptics is one of mostimportant topic in food science and applications biology.[Objects] Investigate the antibacterial activities of MCMVO and its maincomposition on common food-origin bacteria and spoilage bacteria of chilledmeat; Preliminary study the mechanism of antibacterial effects ofMCMVO; Investigate the preparation craft of MCMVO microcapsule.[Methods] Compared the antibacterial activities of MCMVO on commonfood-origin bacteria and spoilage bacteria of chilled meat to commonly used foodpreservatives with the cup method in vitro; Investigate the mechanism of antibacterialeffects of MCMVO and thymol by contrasting the effects of growth curves, proteinutilization of Staphylococcus aureus and the germination spores of Aspergillus flavuslink, and the images of the Staphylococcus aureus under TEM and Aspergillusflavuslink under SEM effected by thymol;Investigate the preparation craft of MCMVOmicrocapsule by spray drying.[Results] 1. The MCMVO has certain antibacterial activities on the growth offood-origin bacterias .The minimal inhibitory and bacteriocidal concentrations forStaphylococcus aureus, Streptococcus pneumoniae and Salmonella S. enterica were0.3125mg/mL, 0.625 mg/mL.2. The MCMVO, thymol and carvacrol has certain anti-fungi effects on the food-originfungi.3. The Micrococcus, Pseudomonas and Staphylococcal were isolated from the chilledmeat. The MIC of MVMCO on that three spoilage bacteria were 0.3125、0.625、2.5mg/mL, and MBC were 0.625、1.25、5mg/mL.4. The thymol, carvacrol and MCMVO can inhibit the protein exploitation of Staphylococcus aureus. The cell membrane partially appears crevice and obviouscytoplasm-wall separation,and the cytoplasm was partially agglutinated.5. The thymol can inhibit the germination of Aspergillus flavus link’s spores. Thesurface of spores became smoothly and hollowly, and the mycel appears retortion, fewbranch and smoothly too.6. The preparing craft of MCMVO microcapsule as follow: The proportion of coreand wall material was 1mL: 6g; The concentration of emulsifier was 0.05％; Theconcentration of slurry was 30g/L.[Conclusions] 1. The MCMVO and its main chemical compositon have certaininhibitory effects on the growth of common food-origin bacteria.2. The MCMVO and its main chemical compositon have certain inhibitory activitieson the growth of spoilage bacteria in the chilled meat.3. The MCMVO and its main chemical compositon can inhibit the growth of bacteria,the protein utilization and the germination of spores.4. The craft of MCMVO microcapsule by spray drying is simple and is suitable forproduction of industrialization.更多还原