Alkaline isolation of soluble β-glucan from spent wine yeast

Primjena β-glukana je moguća u kozmetičkoj industriji te proizvodnji hrane i krmiva, kao i u humanoj i veterinarskoj medicini. U ovom radu topljivi β-glukan je ekstrahiran alkalnim postupkom iz otpadnog vinskog kvasca. Analizirani su kemijski sastavi polazne sirovine i međuproizvoda u različitim fazama alkalne ekstrakcije kao i konačni proizvod, a također su na temelju dobivenih podataka izračunati materijalna bilanca procesa i normativ proizvodnje. Sirovi polisaharidni preparat je osušen na zraku i sadržavao je 97,89 % suhe tvari te 18,54 % ukupnih ugljikohidrata u suhoj tvari. Dio sirovog preparata je dijaliziran i liofiliziran, a pročišćeni polisaharidni preparat sadržavao je 54,96% ugljika, 33,51% kisika i male udjele natrija, sumpora, kalija i fosfora. Snimljeni su i uspoređeni FT-IR spektri dobivenih polisaharidnih preparata. Primjenom triju različitih metoda potvrđena je antioksidacijska aktivnost pročišćenog polisaharidnog preparata.Application of β-glucans is possible in cosmetic, food and feed industries, as well as in human and veterinary medicine. In this work, alkaline procedure was used for extraction of alkali-soluble β-glucan from spent wine yeast. Chemical compositions of raw-material, intermediate products of the applied alkaline isolation as well as final product were compared. Material balance and process yield were calculated from the obtained data. Crude polysaccharide was air-dried and contained 97.89 % of dry weight in which 18.54% of total carbohydrates. A part of crude preparation was dialysed and lyophilised and the purified polysaccharide preparation contained 54.96% of carbon, 33.51% of oxygen as well as small ammounts of sodium, sulphur, potassium and phosphorus. FT-IR spectra and the elemental composition of crude and purified polysaccharide preparations were recorded and compared. Antioxidative activity of the purified polysaccharide preparation was confirmed by three different methods