3.1. Plant Material and Extraction Procedure

Plant material was purchased from a local certified herbal store. Herbs were collected on controlled and ecological plantations. No chemical fertilizers nor plant protection products were used for the cultivation. In addition, after obtaining the plant material, a preliminary selection was carried out, paying particular attention to chemotaxonomic factors. All plants were collected in 2019. The flowers of KTE were collected in June, while the herb of the EAE and GCEin July.

As part of this work, extracts of Centella asiatica L., Clitoria ternatea L. and Epilobium angustifolium L. were prepared. KTEflowers and GCE and EAE herbs were used to prepare the extracts. For this purpose, ultrasound assisted extraction (UAE) was used. A mixture of water and ethanol (80:20 v/v) was used as the extractant. A total of 5 g of plant material and 95 g of mixture were used to prepare each of the extracts. The ultrasonic cleaner mixtures were extracted at room temperature (about 22 °C) for 80 min (8 cycles of 10 min). The resulting extracts were then collected and filtered three times through Whatman No. 10 filter paper using vacuum filtration. The extracts were then evaporated using a vacuum evaporator and stored in the dark at 4 °C until further analysis.