Department of Technology, Regional Campus of Umuarama, State University of Maringá, Umuarama-PR, Brazil.
Nat Prod Res. 2012;26(18):1721-3. doi: 10.1080/14786419.2011.605365. Epub 2011 Oct 14.
The use of essential oils (EOs) in functional foods containing probiotic microorganisms must consider the antimicrobial activity of these oils against beneficial bacteria such as Lactobacillus rhamnosus. This study aimed to evaluate the sensitivity of L. rhamnosus cultures treated with cinnamon EO through viable cell counts and visualisation by transmission electron microscopy. Cinnamon EO at a concentration of 0.04% had a bacteriostatic activity after 2 h of incubation. Although slight alterations were detected in the cell structure, this concentration was considered to be bactericidal, since it led to a significant reduction in cell numbers after 24 h. On the other hand, cinnamon EO at a 1.00% concentration decreased cell counts by 3 log units after 2 h incubation and no viable cell count was detected after 24 h. Transmission electron microscopy indicated that cells treated with 1.00% cinnamon EO were severely damaged and presented cell membrane disruption and cytoplasmic leakage.
在含有益生菌微生物的功能性食品中使用精油（EOs）时，必须考虑这些油对有益细菌（如鼠李糖乳杆菌）的抗菌活性。本研究旨在通过活菌计数和透射电子显微镜观察来评估肉桂精油处理的鼠李糖乳杆菌培养物的敏感性。肉桂精油在 0.04%的浓度下孵育 2 小时后具有抑菌活性。尽管在细胞结构上检测到轻微的改变，但由于它在 24 小时后导致细胞数量显著减少，因此该浓度被认为是杀菌性的。另一方面，肉桂精油在 1.00%的浓度下孵育 2 小时后降低了 3 个对数单位的细胞数，24 小时后未检测到活菌数。透射电子显微镜表明，用 1.00%肉桂精油处理的细胞受到严重损伤，呈现细胞膜破裂和细胞质泄漏。
