Scientific studies on silver fir extracts prove their healing potential in the fields of lowering blood glucose, cardiovascular diseases, joint diseases, psoriasis treatment and also in the treatment of cancer. Their healing power is given by various bioactive compounds such as polyphenols, which are mainly represented by lignans. There are many extraction procedures for obtaining silver fir extracts; among them green extraction technologies have become increasingly popular, such as subcritical water extraction.
In the master 's thesis, we analysed the composition of silver fir extracts obtained with subcritical water extraction and compared them with extracts obtained with supercritical CO2 extraction, high-pressure alcohol extraction followed by flushing with supercritical CO2, industrial water extraction and laboratory water extraction. Using high-performance liquid chromatography (HPLC), we analysed lignans in the extracts (isolariciresinol, hydroxymatairesinol, sekoizolariciresinol, lariciresinol, pinoresinol, matairesinol), with gas chromatography-mass spectrometry (GC-MS) we analysed the presence of volatile compounds, with Folin-Ciocalteu method we analysed the total phenolic compounds, and the antioxidative activity of individual extracts was determined by the DPPH and ABTS•+ methods.
We found that the qualitative and quantitative composition of silver fir extracts strongly depends on the extraction method, and also on the part of the silver fir tree (branches, bark). The highest total phenolic compounds, antioxidant activity and concentration of extracted lignans were discovered in silver fir bark samples, and the highest content of volatile compounds (terpenes and terpenoids) in silver fir branch samples. The most efficient method in our research was proven to be subcritical water extraction; therefore, we conclude that this technique represents great potential in obtaining silver fir extracts and other plant extracts.
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