Production of Single-Cell Protein from Ram Horn Hydrolysate

Candida utilis NRRL Y-900 was grown on horn hydrolysate for single-cell protein production. First, ram horns obtained from slaughterhouse in Erzurum were hydrolyzed by physical and chemical methods and crude horn hydrolysate (CHH) was obtained. The contents of protein, nitrogen, ash, some minerals, total sugars and amino acids of CHH were determined and it was seen that it has sufficient organic and inorganic materials to allow its use as a substrate source in the production of single-cell protein. The CHH was enriched by addition of yeast extract, glucose and KH2PO4. The effects of different CHH concentrations (1, 2, 3, 4, 5, 6, 7, 8, 9 and 10%) on the growth of C. utilis were investigated and 4% of CHH (Horn Broth=HB) was found to be optimal. The biomass yield of C. utilis and its protein content were found to be 6.8 g l-1 and 49.8% respectively. On the other hand, biomass contained 5.4% lipids, 5.94% RNA, 1.53% DNA and 9.7% ash. The biomass contained all of the essential amino acids and when compaired with FAO reference protein it showed a good profile. The results demonstrated that ram horns can be used as a substrate source in the production of single-cell protein.