The occurrence of glucobrassicin, neoglucobrassicin and 4-methoxy-glucobrassicin in roots of Capparis spinosa is demonstrated by HPLC and mass spectral methods, and discussed with respect to the detection of a 4-methoxy-oxindole in roots of Capparis tomentosa; Analyses of fatty acids of seed lipids in five species of Mentha from different localities in Serbia are reported. Samples of five species of Mentha collected in different localities in Serbia (Fig. 1) were analysed for fatty acid composition of seed lipids. Results (Table 1) suggest low intraspecific variability of fatty acid composition and show that seed oils of all investigated species belong to the high linolenic acid type of seed oils as is usual for members of Saturejoideae sensu Wunderlich (i.e. Labiatae with trinucleate and hexacolpate pollen) [1, 2].