Determination of the possibilities of using ferulic acid extracted from einkorn (Triticum monococcum) and emmer (Triticum dicoccum) wheat as functional food component

Ferulic acid (C10H10O4), a phenolic acid commonly found in plants, is a member of the hydroxycinnamic acid family and has antioxidant, antimicrobial, anti-inflammatory, anticarcinogenic, UV protective and antidiabetic activities. It is reported that this important compound, which stands out with its functional properties and is among our import items, is found in high amounts especially in the bran fractions of cereals, and in addition, Einkorn (Triticum monococcum) and Emmer (Triticum dicoccum) wheat varieties, which are known as historical wheat varieties in our country, are reported to be significantly higher in the bran fractions compared to modern wheat. The aim of this doctoral thesis is to determine the ferulic acid rich variety and fraction by analyzing different fractions of Einkorn and Emmer wheat varieties, to extract and purify ferulic acid from the identified variety and fraction, to perform structural analysis of the purified material, to perform antioxidant activity, free radical analysis, total phenolic content, antimicrobial activity and Anticarcinogenic activity tests on the related material and to compare some food products produced using the variety determined as rich in ferulic acid in terms of ferulic acid levels. Within the scope of the studies, Einkorn and Emmer wheat samples were obtained from Tübitak 214O401 project and brought to the laboratory environment, separated from the husks and flour and bran fractions were obtained. Ferulic acid amounts in the samples were determined using high performance liquid chromatography (HPLC). As a result of the analysis, since ferulic acid was found in high amounts in the bran fraction of Einkorn 6 variety, purification processes were carried out using this fraction. Column chromatography, solvent extraction, supercritical carbon dioxide extraction and enzymatic method (feruloyl esterase) were used in purification studies. The material obtained as a result of purification was subjected to structural analysis using mass spectrometry, NMR and FTIR devices and then antioxidant capacity by ABTS, DPPH and Folin Ciocalteu methods, cell viability by MTT method, cell migration tests, antimicrobial by well method and Anticarcinogenic activity experiments in human melanoma (SK-MEL-30) cell line were performed using pure material and ferulic acid analytical standard. Within the scope of their evaluation as functional food components, normal bread, whole wheat bread, bulgur, noodles, and semolina were produced from Einkorn and Emmer wheat varieties and ferulic acid levels in the products were compared with commercial products. According to the results obtained, 1323,70±667,55 ppm (n=15) and 1629,87±456,72 ppm (n=15) was determined in the bran fractions of Einkorn and Emmer wheat varieties, respectively. However, the highest level of ferulic acid was determined as 2953,93±3,16 ppm in the bran fraction obtained from Einkorn 6 wheat variety in Einkorn group and 2232,28±2,15 ppm in the bran fraction of Emmer 25 in Emmer group. Purification studies were carried out using Einkorn 6 wheat bran fraction in which ferulic acid was detected at the highest rate and it was concluded that 22% ferulic acid was purified by supercritical carbon dioxide extraction method, 28% by solvent extraction method and 68% by enzymatic method. In the bioactivity studies performed with the purified material, 1007.81 µg/100 g, 128.9 µg/100 g and 138.35 µg/100 g were found in ABTS DPPH and Folin Ciocalteu assays, respectively, and the values obtained were found to be compatible with the equivalent concentration of the analytical standard. In the antimicrobial susceptibility test, it was concluded that ferulic acid had low activity on Staphylococcus aureus ATCC 25923 and Escherichia coli ATCC 25922 bacteria compared to the data in the EUCAST guidelines. According to the results of the cell viability test performed in SK MEL 30 cell line within the scope of anticarcinogenic activity tests, it was determined that ferulic acid at a concentration of 1500 µM reduced the activity of melanoma cells below 30% after 72 hours. In the cell migration test, it was concluded that SK-MEL-30 cells at the end of 72 hours did not close the distance between the cells when 2 mM ferulic acid dose was applied, thus reducing the interaction between melanoma cells. Einkorn 6 wheat variety with the highest ferulic acid content was used in the production of functional food rich in ferulic acid and ferulic acid levels were determined as 97.74±8.01 ppm in normal bread, 528.12±26.43 ppm in whole wheat bread, 831.01±309.47 ppm in bulgur, 84.05±7.02 in noodles and 694.16±278.25 ppm in semolina. In conclusion, ferulic acid was highly detected in the bran fraction of Einkorn, one of our historical wheat varieties, and its biological activities were highly detected in antioxidant capacity and anticarcinogenic tests. Therefore, the related wheat variety and its fraction have the potential to be used as a functional food component and it is hoped that the data obtained in this thesis will shed light on the studies in this context.