Abstract
Onosma species have long been used traditionally for respiratory tract infections, abdominal pain, wound treatment, burns, and constipation. This study aims to investigate the chemical composition and in vitro antioxidant and enzyme inhibitory activities of ethyl acetate (EtOAc), methanol (MeOH), and water extracts of Onosma mollis DC. MeOH extract was richer in both phenolics and flavonoids than other extracts (44.06 mg GAEs/g and 41.57 mg QEs/g, respectively). The findings obtained from the results of the chromatographic analysis also supported the results of the spectrophotometric analysis. The MeOH extract was the richest in terms of most of the phytochemicals screened. Apigenin 7-glucoside, luteolin 7-glucoside, rosmarinic acid, vanillic acid, and pinoresinol were over 1000.0 μg/g in MeOH extract. The extract in question showed the highest activity in phosphomolybdenum, DPPH, and ABTS radical scavenging and CUPRAC and FRAP reducing power activity assays (2.01, 3.33, 2.30, 1.48, and 0.79 mg/ml, respectively). The water extract presented the highest activity in the ferrous ion chelating assay (1.01 mg/ml). While EtOAc extract showed high activity in acetylcholinesterase (AChE), butyrylcholinesterase (BChE), and α-glucosidase inhibitory activity tests (1.11, 1.49, and 1.07 mg/ml, respectively), MeOH extract showed significant efficacy in tyrosinase and α-amylase inhibitory activity assays (2.94 and 2.08 mg/ml, respectively). There was a high correlation between the total phenolics/flavonoids of the extracts and their antioxidant activities (correlation coefficients were over 0.9). In addition, the phytochemicals mentioned above were found to contribute significantly to the antioxidant activity. It was concluded that a more detailed analysis should be done to determine the compounds responsible for the enzyme inhibitory activities of the extracts.
Highlights
Plants and plant-based nutrients are an indispensable part of the human diet
Studies have shown that plant-derived flavonoids, some alkaloids, phenolic compounds, some diterpenoids, and sulfur compounds have a high degree of antioxidant activity [4,5,6]. ese compounds help protect our body from the harmful effects of these compounds by eliminating oxidant substances that occur due to both normal metabolic reactions and some environmental conditions. erefore, plants continue to be of great interest as additional sources of antioxidant compounds [4, 5, 7,8,9,10]
E phytochemical composition data of the extracts obtained by spectrophotometric method are given in Table 1. e total amount of phenolic compounds of the extracts was found to be higher than the total amount of flavonoid compounds. e total amounts of phenolic and flavonoid compounds of the MeOH extract were 44.06 mg GAEs/g and 41.57 mg QEs/g, respectively. e EtOAc extract was extremely poor in these compounds (20.43 mg GAEs g and 1.69 mg QEs/g, respectively)
Summary
Plants and plant-based nutrients are an indispensable part of the human diet. Many researchers agree that, in addition to fruits and vegetables, many medicinal and aromatic plants that we consume in our daily lives serve as an additional source of natural antioxidants [1,2,3,4]. Studies have shown that plant-derived flavonoids, some alkaloids, phenolic compounds, some diterpenoids, and sulfur compounds have a high degree of antioxidant activity [4,5,6]. Erefore, plants continue to be of great interest as additional sources of antioxidant compounds [4, 5, 7,8,9,10]. Various strategies have been developed to treat this health problem. Some of these strategies are targeting amyloid-beta (Aβ) aggregation and modulating enzymes responsible for metabolizing the amyloid precursor protein (APP) or tau phosphorylation [12]
Sign-in/Register to view highlights & summary Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
