Laboratory of Organic Chemistry LR17ES08, Natural Substances Team, Faculty of Sciences of Sfax, University of Sfax, P.B 1171, Sfax 3000, Tunisia.
Laboratory of Environmental Sciences and Sustainable Development "LASED", Sfax Preparatory Institute for Engineering Studies, University of Sfax, P.B 1171, Sfax 3000,Tunisia.
Molecules. 2023 May 7;28(9):3947. doi: 10.3390/molecules28093947.
stems were harvested in two seasons: winter and spring (February and May 2021). In this study, we investigated the antioxidant (DPPH, ABTS, FRAP and TAC) and antimicrobial activities, total phenolic contents and total flavonoid contents of the obtained extracts (hexane, ethyl acetate and methanol). The results showed that ethyl acetate extract from stems harvested in winter exhibited the highest antioxidant activity, while ethyl acetate extract from the stems harvested in spring showed the most potent antibacterial and antifungal activities. To explain these differences, we investigated the phytochemical composition of these two extracts using liquid chromatography coupled with mass spectrometry. Therefore, 45 compounds were detected, from which we identified 20 compounds (flavonoids, triterpenoids, chalcones and phenolic acids); some were specific to the harvest month while others were common for both periods. Some of the major compounds detected in ethyl acetate (spring) were dihydrochalcone (Kanzonol Y, 8.2%) and flavanone (sophoraflavanone G, 5.9%), previously recognized for their antimicrobial effects. We therefore concluded that the difference in activities observed for the two harvest periods depends on the chemical composition of the extracts and the relative abundance of each compound.
茎分别在两个季节（2021 年 2 月和 5 月）收获：冬季和春季。在这项研究中，我们研究了获得的提取物（正己烷、乙酸乙酯和甲醇）的抗氧化（DPPH、ABTS、FRAP 和 TAC）和抗菌活性、总酚含量和总黄酮含量。结果表明，冬季收获的茎的乙酸乙酯提取物表现出最高的抗氧化活性，而春季收获的茎的乙酸乙酯提取物表现出最强的抗菌和抗真菌活性。为了解释这些差异，我们使用液相色谱-质谱联用技术研究了这两种提取物的植物化学成分。因此，检测到 45 种化合物，从中鉴定出 20 种化合物（类黄酮、三萜、查尔酮和酚酸）；有些化合物特定于收获月份，而有些则在两个时期都有。在乙酸乙酯（春季）中检测到的一些主要化合物是二氢查尔酮（坎佐诺尔 Y，8.2%）和黄烷酮（槐属黄烷酮 G，5.9%），它们以前因其抗菌作用而被识别。因此，我们得出结论，两个收获期观察到的活性差异取决于提取物的化学成分和每种化合物的相对丰度。
