Profiling of the bioactive components of safflower seeds and seed oil: cultivated (Carthamus tinctorius L.) vs. wild (Carthamus oxyacantha M. Bieb.)

Abstract

The composition of lipophilic and hydrophilic components in cultivated (C. tinctorius) and wild (C. oxyacantha) safflower seed oils was studied. By LC–HRMS/MS2, a total of seven highly abundant bioactive compounds with hydrophilic nature, a lignan glycoside (tracheloside), two flavonoids (acacetin–glucuronide pentoside and acacetin-7-O-D-glucuronide), and four alkaloids (N-coumaroylserotonin glucoside, N-feruloylserotonin glucoside, N-coumaroylserotonin, and N-feruloylserotonin), in seeds of both species, were identified. Only a minor part of the hydrophilic compounds (≤ 0.05%) present in the seeds was transferred into the seed oil during the extraction. The linoleic (~ 78%), oleic (~ 15%), palmitic (~ 5%), and stearic (~ 2%) acids—constituted 99% of all detected fatty acids in both species. α-Tocopherol was a main form of tocochromanols (over 94%) in both safflower seed oils. β-Sitosterol was the predominate form (over 36%) of phytosterols, while high levels were also recorded for gramisterol (17.1%) and avenasterol (19.6%) in C. oxyacantha and C. tinctorius seed oils, respectively. Zeaxanthin was a predominated form of carotenoids (over 37%), while high levels were recorded for lutein and β-carotene 15 and 25%, mainly in C. oxyacantha. The total amount of minor lipophilic compounds such as tocochromanols, carotenoids and sterols in C. oxyacantha vs. C. tinctorius seed oil was 57.9 vs. 58.2, 0.76 vs. 0.5, and 185.5 vs. 274 mg/100 g oil, respectively. The presence of squalene was detected only in C. oxyacantha (10.4 mg/100 g oil). Despite the similar composition and levels of fatty acids and tocochromanols, species differed by the phytosterols, carotenoids, and bioactive compounds with hydrophilic nature.