Natural variability in phytosterols in almond (Prunus amygdalus) trees growing under a southern Mediterranean climate

Almond (Prunus amygdalus) kernels are an important source of phytosterols that are considered essential elements for human health. Little information is available on the variability and composition of phytosterols in cultivated almond, and there is no information on wild almond such as those that have originated in Morocco. High levels of variability in phytosterol concentrations were found among 23 accessions of Moroccan almond, ranging from 1,174 - 2,072 mg kg(-1) kernel dry weight, and from 2,184 - 3,582 mg kg(-1) for oil phytosterol, within the ranges published for other almond genotypes. Major components of the phytosterol fraction were beta-sitosterol [55.9 - 84.6% (w/w)] and Delta(5)-avenasterol [8.5 - 28.2%(w/w)]. Significant differences in phytosterol concentrations and compositions were observed between almond seedlings as well as between almonds of different geographical origin, possibly due to a positive effect of higher temperatures. Some genotypes, such as A14 with high concentrations of phytosterols (3,582 mg kg(-1) of oil phytosterol) could be used as parents in almond breeding programmes to add value to local products, and to improve human health.