• fitoestrogeni
• isoflavonoidi
• HPLC
• Medicago sativa L.

In functional food field the research of nutraceutical compounds plays a very important role. Among the nutraceuticals, phytoestrogens are one of the most interesting categories. They are able to bond the animal and human estrogen receptor acting similarly to endogen hormone and consequently influencing the hormone related diseases. Alfalfa is rich in compounds which act as phytoestrogens. These compounds belong to the category of isoflavonoids. In this study we aim at indentifying and quantifying the flavonoids and isoflavonoids in 15 Czech cultivars grown in three experimental fields. Moreover, this work finds out the correlation between phenolics compounds content and characteristics of the plants such as the stems features and the cultivars or the field influence .
An High performance liquid chromatography (HPLC) coupled with a Diode array detector (DAD) method has been developed in order to succeed in the quantification and a first identification of these compounds.
A liquid chromatography-mass spectrometry (LC-MS) set up for the identification of 54 phenolic compound has been performed in order confirm the previous results. Coumestrol and Apigenin resulted as the isoflavonoid and the flavone, respectively, with the major concentration among their classes.
The quantification focused on six selected peaks that were characteristic of all the samples. A statistical analysis of the data led us to identify Morava as the variety with the highest content of coumestrol followed by Zuzana and Litava, while the variety Jarka has the lower concentration, in the range of 15.5 µg/g to 52.2 µg/g. The apigenin content was relatively higher if compared with the coumestrol content. It ranged from of ZE XLII to 94.0 µg/g of Holyna, Morava and Zuzana. Thus, Morava and Zuzana results as the varieties with the highest concentration of both the compounds. Statistical analysis showed also the influence of the original field where the plants were grown on the concentration of the selected compounds. The field C seems to enhance the concentration of Apigenin this is probably due to particular environmental condition. Analyzing the obtained data there is no correlation between apigenin and coumestrol content neither between coumestrol content and stem features.