Chemistry Department, Federal University of Lavras (UFLA), Lavras, 37200-900 MG, Brazil.
Engineering Department, Federal University of Lavras (UFLA), Lavras, 37200-900 MG, Brazil.
FEMS Microbiol Lett. 2024 Jan 9;371. doi: 10.1093/femsle/fnae083.
Food contamination by mycotoxigenic fungi is one of the principal factors that cause food loss and economic losses in the food industry. The objective of this work was to incorporate the essential oil from Corymbia citriodora Hook and its constituents citronellal and β-citronellol into poly(lactic acid) nanofibers; to characterize the nanofibers by scanning electron microscopy (SEM), Fourier transform infrared spectroscopy and differential scanning calorimetry; to evaluate the antifungal activity by the fumigation method; to evaluate the antimycotoxigenic activity against Aspergillus carbonarius, Aspergillus ochraceus, Aspergillus westerdijkiae, Aspergillus flavus, and Aspergillus parasiticus; and to evaluate the morphology of these microorganisms. All the nanofibers had a regular, smooth, and continuous morphology. FTIR analyses confirmed that the active ingredients were incorporated into the polymer matrix. All samples exhibited antifungal and ochratoxigenic inhibitory activities of up to 100% and 99%, respectively, with the best results observed for (PLA + 30 wt% β-citronellol) nanofibers and (PLA + 30 wt% citronellal) nanofibers. However, 100% inhibition of the production of aflatoxin B1 and B2 was not observed. The images obtained by SEM indicated that the nanofibers caused damage to the hyphae, caused a decrease in the production of spores, and caused deformation, rupture, and non-formation of the conid head, might be an alternative for the control of mycotoxigenic fungi.
真菌毒素产生菌对食物的污染是导致食品工业中食物损耗和经济损失的主要因素之一。本工作的目的是将柠檬桉（Corymbia citriodora Hook）精油及其成分香茅醛和β-香茅醇掺入聚乳酸纳米纤维中；通过扫描电子显微镜（SEM）、傅里叶变换红外光谱（FTIR）和差示扫描量热法（DSC）对纳米纤维进行表征；通过熏蒸法评估其抗真菌活性；评估其对赭曲霉（Aspergillus carbonarius）、桔青霉（Aspergillus ochraceus）、威地曲霉（Aspergillus westerdijkiae）、黄曲霉（Aspergillus flavus）和寄生曲霉（Aspergillus parasiticus）的抗真菌活性；并观察这些微生物的形态。所有纳米纤维均具有规则、光滑和连续的形态。FTIR 分析证实了活性成分已掺入聚合物基质中。所有样品均表现出高达 100%和 99%的抗真菌和产赭曲霉毒素抑制活性，其中（PLA+30wt%β-香茅醇）纳米纤维和（PLA+30wt%香茅醛）纳米纤维的效果最佳。然而，并没有观察到对黄曲霉毒素 B1 和 B2 的产生抑制达到 100%。SEM 图像表明，纳米纤维导致菌丝损伤，孢子产生减少，并且导致分生孢子头变形、破裂和无法形成，这可能是控制产真菌毒素真菌的一种替代方法。
