Total phenolics and phenolic acids content in low (Chrysopogon gryllus) and mediocre quality (Festuca vallesiaca) forage grasses of Deliblato Sands meadow-pasture communities in Serbia

Chrysopogon gryllus and Festuca vallesiaca are components of a number of meadow-pasture com- munities in Serbia. We performed the analyses of phenolics that influence quality and digestibility of grasses to a great extent. Total phenolics were measured spectrophotometrically and phenolic acids by HPLC analysis. The aboveground parts of C. gryllus contained 10.6 mg/g whereas F. vallesiaca of 21.6 mg/g total phenolics. Bound phenolics dominated over free ones in both species. The content of both free and bound p-coumaric, ferulic, p-hydroxybenzoic and syringic acid was higher in C. gryllus (6.34 mg/g) than in F. vallesiaca (3.96 mg/g). Deriva- tives of cinnamic acid prevailed in both species compared to the benzoic acid derivatives. Low quality of C. gryllus is connected with its high tissue phenolic acids and mediocre quality of F. vallesiaca with the high content of total phenolics that act unfavourably on digestibility of such grasses.