*Article* **Immunomodulatory Properties of Polysaccharide-Rich Young Green Barley (***Hordeum vulgare***) Extract and Its Structural Characterization**

**Marta Kinga Lemieszek 1,\* , Iwona Komaniecka <sup>2</sup> , Michał Chojnacki <sup>1</sup> , Adam Choma <sup>2</sup> and Wojciech Rzeski 1,3**


**Abstract:** Young green barley (YGB) water extract has revealed a beneficial impact on natural killer (NK) cells' ability to recognize and eliminate human colon cancer cells, without any side effects for normal colon epithelial cells. The direct anticancer effect of the tested compounds has been also shown. The mixture of oligosaccharides found in this extract was characterized by chemical analyses and via FT-IR spectroscopy and MALDI-TOF MS techniques. The YGB preparation contained 26.9% of proteins and 64.2% of sugars, mostly glucose (54.7%) and fructose (42.7%), with a small amount of mannose (2.6%) and galactose (less than 0.5%). Mass spectrometry analysis of YGB has shown that fructose oligomers contained from 3 to 19 sugar units. The number of fructans was estimated to be about 10.2% of the dry weight basis of YGB. The presented results suggest the beneficial effect of the consumption of preparations based on young barley on the human body, in the field of colon cancer prevention.

**Keywords:** cancer immunotherapy; fructan; FT-IR; mass spectrometry; young green barley
