College of Life and Environmental Sciences, Shanghai Normal University, Shanghai, China.
College of Life Science and Technology, Harbin Normal University, Harbin, China.
PLoS One. 2019 Jan 2;14(1):e0200174. doi: 10.1371/journal.pone.0200174. eCollection 2019.
Flavonoids are secondary metabolites of plants that often have medical applications. The influences of different sample drying pretreatments on flavonoids and antioxidant activity of ferns have not studies. Dryopteris erythrosora leaves used to analyze flavonoid alterations resulting from drying pretreatments. The total flavonoid content of D. erythrosora leaves exposed to different pretreatments was significantly different. The total flavonoid content of samples initially air-dried in shade and then oven-dried at 75°C were the highest (7.6%), while samples initially dried at 75°C had the lowest content (2.17%). Antioxidant activities of D. erythrosora leaves with different pretreatments varied. Group B first air-dried in the shade and then oven-dried at 75°C and group C first air-dried in the sun and then oven-dried at 75°C, both showed relatively stronger antioxidant activity. The best pretreatment for preserving the flavonoids was to first dry the plant material in the shade and then complete the drying process in an oven at 75°C. It was tentatively identified 22 flavonoids among the four different pretreatments by HPLC-ESI-TOF-MS.
类黄酮是植物的次生代谢物，通常具有医疗应用。不同的样品干燥预处理对蕨类植物类黄酮和抗氧化活性的影响尚未研究。本研究采用干燥预处理来分析旱蕨叶片中类黄酮的变化。不同预处理旱蕨叶片的总黄酮含量差异显著。先在阴凉处风干然后在 75°C 下烘干的样品总黄酮含量最高（7.6%），而先在 75°C 下干燥的样品总黄酮含量最低（2.17%）。不同预处理旱蕨叶片的抗氧化活性也有所不同。先在阴凉处风干然后在 75°C 下烘干的 B 组和先在阳光下风干然后在 75°C 下烘干的 C 组，均表现出相对较强的抗氧化活性。保留类黄酮的最佳预处理方法是先将植物材料在阴凉处干燥，然后在 75°C 的烘箱中完成干燥过程。通过 HPLC-ESI-TOF-MS 对四种不同预处理方法中共鉴定出 22 种类黄酮。
