Unité de Physiologie et Biochimie de la Tolérance au Sel des Plantes, Départamento de Biologie, Faculté des Sciences de Tunis, Campus Université, 2092 Tunis, Tunisie.
J Food Sci. 2012 Oct;77(10):C1047-54. doi: 10.1111/j.1750-3841.2012.02904.x. Epub 2012 Sep 14.
Variation in the composition of Origanum majorana L. essential oil (EO) and fatty acids were studied under salt treatment. Plant material has been harvested at 2 phenological stages: early vegetative stage (EVS) and late vegetative stage (LVS) or prefloral. Our results showed that the application of 75 mM NaCl increased total lipid contents in marjoram shoots and caused great qualitative changes in the fatty acids profiles. NaCl treatment reduced and stimulated the EO yields, respectively, at EVS and LVS and induced quantitative changes in the chemical EO composition in shoots. Phenolic contents were higher during the LVS than EVS in the absence and the presence of salt. Under control conditions, RP-HPLC analysis of the methanolic extract of marjoram dried shoots showed a predominance of flavonoid during the EVS whereas phenolic acids predominated during the LVS. However, under 75 mM NaCl, we noted a predominance of flavonoid at LVS and constant levels of phenolic and flavonoid classes at the EVS. For control treatment and at both EVS and LVS, the main components identified were respectively rosmarinic acid gallic as phenolic acids and amentoflavone as flavonoid. In the presence of salt and at the EVS, we observed a significant increase in trans-2 hydrocinnamic, gallic acid and quercetin-3-galactoside contents. However, for the LVS, salt induced a stimulation of gallic acid, apigenin, and amentoflavone. Our results showed that LVS had the highest contents of bioactive compounds, and could be considered as the best stage for harvesting marjoram plants. Practical Application: In this study, the fatty acid composition, essential oil, and phenolic content of Origanum majorana were investigated. This is important for potential application of marjoram as functional food at the late vegetative stage. The richness of O. majorana in volatile and phenolic active compounds known for their antioxidant, antimicrobial, and insecticidal activities could support the utilization of this plant in a large field of application including cosmetic, pharmaceutical, agro alimentary, and biological defense.
盐处理下牛至（Origanum majorana L.）精油（EO）和脂肪酸组成的变化。植物材料在 2 个物候期收获：早期营养期（EVS）和晚期营养期（LVS）或预花期。我们的结果表明，应用 75 mM NaCl 增加了牛至嫩枝中的总脂质含量，并导致脂肪酸谱发生了很大的定性变化。NaCl 处理分别降低和刺激了 EVS 和 LVS 的精油产量，并诱导了嫩枝中精油化学成分的定量变化。在没有和存在盐的情况下，LVS 时酚类含量高于 EVS。在对照条件下，牛至干枝甲醇提取物的 RP-HPLC 分析表明，EVS 时黄酮类化合物占优势，而 LVS 时则以酚酸为主。然而，在 75 mM NaCl 下，我们注意到 LVS 时黄酮类化合物占优势，EVS 时酚类和黄酮类化合物的水平保持不变。对于对照处理和 EVS 和 LVS，鉴定的主要成分分别为酚酸的迷迭香酸和黄酮类化合物的芹菜素。在盐的存在下和 EVS 时，我们观察到反式-2 肉桂酸、没食子酸和槲皮素-3-半乳糖苷含量显著增加。然而，对于 LVS，盐诱导了没食子酸、芹菜素和芹菜素的刺激。我们的结果表明，LVS 具有最高含量的生物活性化合物，可被认为是收获牛至植物的最佳阶段。实际应用：在这项研究中，研究了牛至的脂肪酸组成、精油和酚类含量。这对于牛至作为功能食品在晚期营养期的潜在应用很重要。牛至富含挥发性和酚类活性化合物，这些化合物具有抗氧化、抗菌和杀虫活性，可以支持将这种植物应用于包括化妆品、制药、农业食品和生物防御在内的广泛领域。
