陈皮精油对大肠杆菌的抑菌作用研究

Study on the antibacterial effects of essential oil of dried tangerine peel on Escherichia coli

中文关键词:  陈皮  精油  大肠杆菌  抑菌作用

英文关键词:dried tangerine peel  essential oil  Escherichia coli  antibacterial effect

中文摘要:

      目的 探讨陈皮精油对大肠杆菌的抑菌作用。方法 采用具有代表性的5年广陈皮(Pericarpium citri reticulatae ‘Chachiensis’, PCR-C)和模式大肠杆菌菌株(Escherichia coli, E. coli) ATCC25922进行相关研究, 采用水蒸气蒸馏法进行陈皮精油提取, 采用气相色谱与质谱联用仪分析精油具体化合物成分, 采用全波长酶标仪测定陈皮精油对E. coli的最小抑菌浓度(minimum inhibitory concentration, MIC), 并结合E. coli生长曲线、生物膜形成、胞内大分子物质含量、脂肪酶活性变化, 探究其对大肠杆菌的抑菌机制。结果 (1)陈皮中精油含量为7.42%, 包括46种挥发性化合物, 含量为976.93 mg/g, 其主要成分为单萜烯(13种, 927.72 mg/g, 94.96%), 且以D-柠檬烯(578.31 mg/g, 59.20%)含量最高; (2)陈皮精油对E. coli抑菌作用较强, 最小抑菌浓度为1.28 mg/mL (pH 7.5, 37 ℃), 满足食品添加感官要求; (3)陈皮精油主要通过降低E. coli细胞脂代谢、三磷酸腺苷(5'-adenylate triphosphate, ATP)和生物膜合成, 以及延长细胞适应期和降低细胞生长繁殖, 来实现对E. coli的抑菌作用。结论 陈皮精油对E. coli的抑菌作用较为明显, 具有较好的应用前景。

英文摘要:

      Objective To explore the antibacterial effects of essential oil of dried tangerine peel on Escherichia coli. Methods In this study, the representative 5-years-old Pericarpium citri reticulatae ‘Chachiensis’ (PCR-C) from Guangdong Province and model Escherichia coli (E. coli) ATCC25922 were selected for the relevant research. The essential oil of dried tangerine peel was extracted by steam distillation. The components of essential oil were analyzed by gas chromatography-mass spectrometry, the minimum inhibitory concentration (MIC) of essential oil of dried tangerine peel against E. coli was determined by a full-wavelength microplate reader, and the antibacterial mechanism of essential oil of dried tangerine peel against E. coli was explored by analysis of changes of the E. coli growth curve, biofilm formation, concentration of intracellular macromolecular substance, and lipase activity. Results (1) The ratio of the essential oil of dried tangerine peel was 7.42%, which included 46 kinds of volatile compounds with a total content of 976.93 mg/g identified, the main component of essential oil was monoterpenes (13 species, 927.72 mg/g, 94.96%), and D-limonene (578.31 mg/g, 59.20%) was the highest volatile component amongst all detected compounds. (2) Antibacterial effect of essential oil of dried tangerine peel on E. coli was obvious, and the minimum inhibitory concentration was 1.28 mg/mL (pH 7.5, 37 ℃), which met the sensory requirements of food addition. (3) Essential oil of dried tangerine peel could inhibit E. coli mainly by reducing metabolism of cellular lipid, inhibiting cellular synthesis of 5'-adenylate triphosphate (ATP) and biofilm synthesis, prolonging the adaptation period of cells and reducing cellular growth and reproduction. Conclusion Antibacterial effect of essential oil of dried tangerine peel on E. coli is obvious, and it has good application prospects.