Antioxidant and enzyme inhibition activities of Spartium junceum with HPLC-DAD profiling

Spartium junceum L., a Fabaceae plant, is commonly known as Spanish broom and cultivated in the Mediterranean regions. This study aimed to investigate the chemical profiles and antioxidant and different enzyme inhibitory activities of methanol, ethanol and aqueous extracts obtained from flowers and stems of S. junceum. Also, their phenolic compositions were analyzed by high-performance liquid chromatography with a diode-array detector (HPLC-DAD). The aqueous extract of stems showed the highest phenolic content (63.94mg gallic acid equivalents/g), while the aqueous extract of stems contained the highest flavonoid content (61.33mg quercetin equivalents/g). The stem water extract demonstrated the highest 2,2 '-diphenyl-1-picrylhydrazyl radical-scavenging activity (IC50: 2327 mu g/ml), while the stem water extract exhibited a strong 2,2 '-azino-di(3-ethylbenzothiazoline-6-sulfonic acid) radical-scavenging activity (IC50: 91.80 +/- 0.90 mu g/ml). The tested extracts differed greatly in terms of enzyme inhibition activity. The stem water extract showed the highest anti-acetylcholinesterase activity (IC50: 46.69 +/- 1.66 mu g/ml); however, the stem methanol extract exhibited a strong anti-butyrylcholinesterase activity (IC50: 76.39 +/- 0.27 mu g/ml). The flower methanol extract was the most active against the alpha-glucosidase enzyme (IC50: 296.7 +/- 3.77 mu g/ml). All extracts showed low activities against alpha-amylase and tyrosinase enzymes. The evaluation of the biological activity results provides evidence for bioactivity-guided isolation studies on the active extracts of this plant.

Automated summary

This study investigated the chemical profiles, antioxidant and enzyme inhibitory activities of methanol, ethanol, and aqueous extracts from the flowers and stems of Spanish broom. The stem aqueous extract showed the highest phenolic content and exhibited the strongest antioxidant and anti-acetylcholinesterase activities.