Investigation of enzyme inhibition potentials, and antioxidative properties of the extracts of endemic Stachys bombycina Boiss.Fatma Ayaz, Nuraniye Eruygur
Background and Aims: The genus Stachys L., is represented by around 300 species worldwide. More than 120 taxa, almost 60 of which are endemic, are widely distributed in Turkey, particularly in the eastern and southern regions. Stachys species have traditionally been used for many diseases such as asthma, rheumatism, cough, genital tumors, ulcers, diabetes, hemorrhoids, kidney stones, and various mental disorders. Among the species, S. bombycina Boiss., namely “arıçayçesi” in Turkish, is one of the near-threatened endemic perennial herbs. Methods: The antioxidant activity of methanol and water extracts of S. bombycina was examined utilizing in vitro techniques, including radical scavenging, such as DPPH, and ABTS, an iron-chelating assay, and the total phenol (TPC) and flavonoid contents (TFC). The extracts were also investigated on enzyme inhibition effects using in vitro spectrophotometric method. HPLC analysis was also used for the determination of the phytochemical profiles of the extracts. Results: Based on our results, the methanol extract of S. bombycina demonstrated higher DPPH and ABTS radical scavenging activity with the IC50 value of 605.7 ± 1.04 and 19.40 ± 0.37 µg/mL, respectively, than the water extract. Otherwise, the water extract was found to have a higher iron chelating activity (IC50= 917.9 ± 3.55 µg/mL) than the methanol extract. The highest TPC of the water extract was determined as 81.07 ± 4.71 µg GAE/mg, although the methanol extract had more TFC at 46.93 ± 1.94 µg QE/mg. In addition, high anti- BChE activity was observed (IC50= 58.09 ± 1.18 µg/mL) in the water extract. In addition, ellagic acid was defined as a major component in the methanol extract, while caffeic acid was detected as the main compound in the water extract. Conclusion: Consequently, the current study is the first to report the antioxidant and enzyme inhibitory properties of S. bombycina. According to our findings on S. bombycina, this work can contribute to the development of bioactive agents from natural sources. Moreover, further investigations still need to be conducted on the discovery of the phytoconstituents of S. bombycina responsible for the bioactivity, as well as its potential various biological activities.