肉桂醛纳米乳的制备及其抑菌效果研究

为评价肉桂醛纳米乳对水产动物致病菌的抑菌效果,以吐温-80为表面活性剂、乙醇为助表面活性剂、乙酸乙酯为油相,加蒸馏水按比例配制成空白纳米乳,加入肉桂醛制备得肉桂醛纳米乳,并评价了肉桂醛纳米乳的部分特性;探究肉桂醛纳米乳对迟缓爱德华氏菌(Edwardsiella tarda)、嗜水气单胞菌(Aeromonas hydrophila)、温和气单胞菌(Aeromonas sobria)、鳗败血假单胞菌(Pseudomonas anguilliseptica)4种常见水产动物致病菌的抑菌效果。结果显示,肉桂醛纳米乳中吐温-80、乙醇、乙酸乙酯、蒸馏水和肉桂醛质量比为10∶5∶11∶73∶1,空白纳米乳对肉桂醛的最大载药量为20.11 mg/m L,肉桂醛纳米乳为水包油型淡黄色澄清透明液体,粒径5~20 nm,平均粒径10.74 nm;与同浓度肉桂醛溶液相比,肉桂醛纳米乳具有更强的抑菌活性,在最大载药量时,对嗜水气单胞菌、鳗败血假单胞菌、迟缓爱德华氏菌、温和气单胞菌的抑菌强度分别提高了65.56%、46.99%、41.94%、26.91%。肉桂醛纳米乳对嗜水气单胞菌、温和气单胞菌、鳗败血假单胞菌、迟缓爱德华氏菌的最小抑菌浓度(MIC)分别0.31、0.51、0.72、1.00 mg/m L。研究表明,肉桂醛纳米乳在水产养殖中具有潜在的应用价值。

Preparation of Cinnamaldehyde Nanoemulsion (CNE) and Its Antibacterial Effects

In order to evaluate the antibacterial effect of the cinnamaldehyde nanoemulsion (CNE) against the pathogenic bacteria of aquatic animals, the tween-80 was adopted as surfactant, ethanol as cosurfactant, ethyl acetate as oil phase, along with distilled water, to prepare blank nanoemulsion. Cinnamaldehyde was mixed into the blank nanoemulsion to form the cinnamaldehyde nanoemulsion (CNE). Some physical characteristics of the CNE were evaluated. The antibacterial activity of the CNE against four pathogenic bacteria of aquatic animals, Edwardsiella tarda, Aeromonas hydrophila, Aeromonas sobria, and Pseudomonas anquilliseptica, was compared. The results show that the optimum mass ratio of tween-80 : ethanol : ethyl acetate : distilled water : cinnamaldehyde was 10 : 5 : 11 : 73 : 1. The maximum cinnamaldehyde loading of blank nanoemulsion is 20.11 mg/mL. The oil-in-water CNE is light yellow, clear and transparent, with particle size range from 5 nm to 20 nm, average 10.74 nm. Compared with the same concentration of cinnamaldehyde, the CNE exhibits stronger antimicrobial activity. At 20.11 mg/mL, the antibacterial effect of CNE against A. hydrophila, P. anquilliseptica, E. tarda and A. sobria was enhanced 65.56%, 46.99%, 41.94%, 26.91%, respectively. The Minimal Inhibitory Concentration of CNE against A. hydrophila, A. sobria, P. anquilliseptica and E. tarda was 0.3, 0.5, 0.7 and 1 mg/mL, respectively. These findings demonstrated that CNE owns potential application value in aquaculture.