【作者】 王婷婷；

【导师】 李大鹏；

【作者基本信息】 山东农业大学 ， 食品科学， 2011， 硕士

【摘要】 食品在加工、保藏、流通等环节易受各种微生物的侵染,导致食品的腐败变质。我国传统中药大多具有杀菌或抑菌功效,但单味中药抗菌谱较窄。中药配伍可以有效的增强抗菌活性,拓宽抗菌谱,且具有低毒、不易产生耐药性等优点。据文献记载黄连、黄芩和连翘均有较强的抑菌能力,且毒副作用较小、价格低廉、具有广谱抗菌特点可被进一步开发应用于食品保鲜领域。本研究分析了黄连、黄芩和连翘单药及配对后药对无水乙醇提取物的抑菌功效,筛选出具有较好协同抑菌作用的黄连-连翘药对。通过混料实验设计,优化了黄连-连翘药对的抑菌浓度配比。研究了黄连、连翘单药及药对对鲜切莴苣褐变、鲜切胡萝卜白变及其他贮藏品质的影响,主要研究结果如下:1.通过测定抑菌圈直径和最小抑菌浓度发现:黄连、黄芩、连翘三种中药及其药对的乙醇提取物对七种供试菌均表现出一定的抑制能力;分析单药与药对理论加和值和FIC指标发现:黄连-黄芩及黄芩-连翘两个药对未能表现出明显的协同效果,黄连-连翘药对对七种供试菌均表现出一定的协同或相加效果。2.以藤黄微球菌为例,利用Design Expert软件对黄连-连翘药对体外抑菌协同效应配比进行优化,模型预测黄连、连翘的最佳配比为4.523:5.477,FIC值为0.264375,验证试验得出FIC为0.25,与预测结果基本一致,表明该模型具有良好的适用性。3.低温条件下用中药提取物保鲜鲜切莴苣。与对照组相比,中药处理抑制了鲜切莴苣的褐变,延缓了Vc含量的下降,维持了鲜切莴苣的原有品质,使其货架期延长6d以上;中药处理抑制了木质素含量的增加,从而延缓了鲜切莴苣的木质化进程;此外,中药处理还抑制了纤维素酶活性的降低,减少了纤维素含量的累积,抑制了pH值、菌落总数和PPO、POD活性的上升,但对降低失重率无明显效果。药对处理在抑制纤维素、木质素含量的增加,保持Vc含量,抑制pH值、POD活性和菌落总数上升方面的能力比单药强。4.低温条件下用中药提取物保鲜鲜切胡萝卜。与对照组相比,中药处理抑制了鲜切胡萝卜的白变,延缓了Vc含量的下降,维持了鲜切胡萝卜的原有品质,使其货架期延长10d以上;此外,中药处理还抑制了纤维素、木质素含量的增加,抑制了pH值和PPO、POD活性的上升,但对降低失重率无明显效果。药对处理抑制POD活性上升的能力比单药强。5.通过相关性分析得出,鲜切莴苣贮藏过程中PPO活性与POD活性对褐变、木质素生成均有显著影响;鲜切胡萝卜贮藏过程中POD活性对白变、木质素生成均有显著影响,而PPO活性对其影响不显著。总之,本论文为黄连、连翘复配抑菌及鲜切蔬菜保鲜技术的研究提供了数据参考,也为进一步开发中药复配保鲜剂提供了理论依据。更多还原

【Abstract】 During the process of storage and distribution, food is easy to be infected by a variety of microorganism which may result in food contamination. Most of traditional Chinese medicine has a bactericidal or bacteriostatic effect, but the antimicrobial spectrum of single herb is narrow. The compatibility of medicines can enhance the antibacterial activity and broaden the antimicrobial spectrum effectively, and has low toxicity, resistance and other advantages. According to historical records, Coptis chinensis,Scutellaria baicalensis and Forsythia suspensa have strong antimicrobial activity and less side effects, low price, with broad antimicrobial spectrum characteristics that can be used to further develop in the field of food preservation.This study analyzed the antimicrobial activity of ethanol extracts of single Coptis chinensis, Scutellaria baicalensis, Forsythia suspensa and their pairs, and filtered Coptis chinensis-Forsythia suspensa pair because of their good synergistic inhibitory effect. The vitro synergistic effect of Coptis chinensis-Forsythia suspensa pair was optimizated by mixture experimental design. The effects of Coptis chinensis and Forsythia suspensa on browning of fresh-cut lettuce, WI of fresh-cut carrot and other related indexes were studied.The conclusions are as follows:1.The inhibitory ability of Coptis chinensis, Scutellaria baicalensis, Forsythia suspensa and their pairs on seven tested Bacteria and Fungus was measured based on inhibition zone diameter and MIC which showed some inhibitory capacity; The in vitro synergistic effects of them were obtained by comparison with the theoretical value and the FIC index. Coptis chinensis-Scutellaria baicalensis and Scutellaria baicalensis-Forsythia suspensa pairs failed to show clear synergistic effect while Coptis chinensis-Forsythia suspensa pair showed a certain degree of synergistic or additive effects on the seven tested Bacteria and Fungus.2.To M.luteus, the formula of synergistic effect of Coptis chinensis-Forsythia suspensa pair was optimizated using Design Expert software, and the result showed the best ratio of Coptis chinensis and Forsythia suspensa is 4.523:5.477, and the FIC is 0.264375. The validation experiment with this ratio showed the FIC is 0.25,which is basically consistent with the prediction, so we can consider that the model has good applicability. 3.Chinese herb extracts were used to preserve fresh-cut lettuce under low temperature. Compared with the control groups, traditional Chinese medicine treatment inhibited the browning of fresh-cut lettuce, delayed the decline in Vc content, maintaining the original quality of fresh-cut lettuce, to extend the shelf life of more than 6d; traditional Chinese medicine treatment inhibited the increase of lignin content, thereby delayed the process of lignification of fresh-cut lettuce; In addition, Chinese medicine treatment also inhibited the reduction of cellulase activity, reduced the accumulation of cellulose content, inhibited the increase of pH, total number of colonies and the PPO, POD activity, but no significant effect on reducing weight loss. The ability of pair herbs dealing in the inhibition of increase in cellulose and lignin content, maintain Vc content, inhibition of increase in pH and the total number of colonies is stronger than single herbs.4.Chinese herb extracts were used to preserve fresh-cut carrot under low temperature. Compared with the control groups, traditional Chinese medicine treatment inhibited the WI of fresh-cut carrot, delayed the decline in Vc content, maintaining the original quality of fresh-cut carrot, to extend the shelf life of more than 10d; In addition, Chinese medicine treatment also inhibited the the increase of cellulose and lignin content, inhibited the increase of pH and PPO, POD activity, but no significant effect on reducing weight loss. The ability of pair herbs dealing in inhibition of increase in POD activity is stronger than single herbs.5.According to correlation analysis, during storage of fresh-cut lettuce, PPO activity and POD activity have certain influence on the browning index and the formation of lignin; during storage of fresh-cut carrot, POD activity has certain influence on the browning index and the formation of lignin, but PPO activity has no certain influence on them.In conclusion, this paper provides a data reference for the in vitro synergy antibacterial ability of Coptis chinensis-Forsythia suspensa and preservation technology of fresh-cut vegetables, and also provides a theoretical basis for the further development of traditional Chinese medicine compound preservative.更多还原