Francik Sławomir, Francik Renata, Sadowska Urszula, Bystrowska Beata, Zawiślak Agnieszka, Knapczyk Adrian, Nzeyimana Abdul
Department of Mechanical Engineering and Agrophysics, Faculty of Production Engineering and Energetics, University of Agriculture in Krakow, Balicka 120, 30-149 Krakow, Poland.
Institute of Health, State Higher Vocational School in Nowy Sacz, Staszica 1, 33-300 Nowy Sacz, Poland.
Materials (Basel). 2020 Dec 19;13(24):5811. doi: 10.3390/ma13245811.
The influence of harvest period and drying method of L. leaves on the content of essential oils, polyphenols and antioxidant properties was investigated. Sage leaves were collected twice during plant blossoming (in June and July) and dried traditionally in natural conditions and at 35 °C. Antioxidant activity was assayed in methanol-acetone extracts and infusions of dried leaves with the use of free radical scavenging activity (DPPH) and ferric reducing antioxidant power (FRAP) technique. Total phenolic content in extracts as well as in infusions was determined by the means of Folin-Ciocalteu method. Based on the LC/MS analysis, the polyphenol compounds present in both extracts and in infusions were identified. The extracts contained more polyphenols and were characterized by higher antioxidant activity than infusions. In the extracts significant amount of ferulic acid was found, which was influenced both by the harvest period and drying method. The amount of ferulic acid found in extracts obtained from the June leaves dried traditionally was three times lower (6.185 μg/g DW) than in extracts from July leaves dried in the same conditions. Harvest period had a significant effect on the essential oils' content, leaves collected in July contained 15% more oils than those collected in June.
研究了鼠尾草叶片的采收期和干燥方法对精油、多酚含量及抗氧化性能的影响。在植物开花期间（6月和7月）分两次采集鼠尾草叶片，并在自然条件下和35℃下进行传统干燥。采用自由基清除活性（DPPH）和铁还原抗氧化能力（FRAP）技术，对干燥叶片的甲醇-丙酮提取物和浸液的抗氧化活性进行了测定。采用福林-酚法测定提取物和浸液中的总酚含量。基于液相色谱/质谱分析，鉴定了提取物和浸液中存在的多酚化合物。提取物中含有更多的多酚，并且比浸液具有更高的抗氧化活性。在提取物中发现了大量的阿魏酸，其含量受采收期和干燥方法的影响。传统干燥的6月叶片提取物中阿魏酸含量（6.185μg/g干重）比相同条件下干燥的7月叶片提取物低三倍。采收期对精油含量有显著影响，7月采集的叶片含油量比6月采集的叶片多15%。
