Abstract Exhaustive extraction of alk(en)ylresorcinols (ARs) from biological matrices is a prerequisite for economic screening of extensive plant collections including their rapid quantitation. For this purpose, an ultrasound-assisted extraction protocol was developed to facilitate the liberation of ARs from mango peels (Mangifera indica L.) and rye grains (Secale cereale L.). While maintaining or even improving the extraction efficiency of the analytes, the duration of analytical extraction was shortened from more than 1h to only 45s as compared to previous methods. In addition, sample weight and solvent use were significantly reduced. Besides the validation of the extraction procedure, validation parameters for the HPLC–DAD–MSn based characterisation and quantitation method are provided. In particular, fully satisfactory recovery rates and quantitation limits were achieved, and coefficients of variation (CV) for repeatability and reproducibility were ⩽8 and <5%, respectively. Moreover, a high compound stability was shown for all ARs during storage in methanolic solution at room temperature for 48h and at −80°C for up to 13months. The developed method was exemplified using two mango and three rye cultivars, and the results were compared to previously published data.