Volatile constituents of Festuca nigrescens, Phleum alpinum and Poa alpina from N. W. Italian Alpine pastures.

The composition of the volatile fractions of three important grasses from sub-alpine N.W. Italian pastures, namely Festuca nigrescens Lam. non Gaudin (chewing fescue), Phleum alpinum L. (alpine timothy) and Poa alpina L. (alpine bluegrass) was investigated. The fresh aerial parts were collected at the flowering stage during the summer season. The volatile oils obtained from green tissues by steam distillation in a Clevenger-type apparatus, were analyzed by GC/FID and GC/MS. The oil yield was 0.04 +/- 0.01% weight/fresh weight bases for each of the investigated species. Several classes of compounds were found in the volatile fractions, including aldehydes, alcohols, acids, hydrocarbons, esters, ketones, terpenes, and phenolics. Qualitative and quantitative differences were observed.

Volatile constituents of Trifolium pratense and T. repens from N.E. Italian alpine pastures.

The composition of the volatile fraction of two important forage legumes from Italian sub-alpine N.E. pastureland, namely Trifolium pratense L. subsp. pratense (red clover) and T. repens subsp. repens (white clover) were investigated. The volatile oil was obtained from the fresh aerial parts by steam distillation and analyzed by GC/FID and GC/MS. The oil yield was 0.018 and 0.021% (weight/fresh weight basis) for T. pratense and T. repens, respectively. Several classes of compounds were found in both the oils, including alcohols, aldehydes, ketones, terpenes, esters, hydrocarbons, phenolics and acids. Qualitative and quantitative differences were found.