Microwave-Assisted Extraction of Polyphenolics from Some Selected Medicinal Herbs Grown in Turkey

Abstract

Abstract:The effect of microwave-assisted extraction (MAE) process on the antioxidant capacity/activity of three medicinal herbs from Turkey was investigated by electrochemical differential pulse voltammetric (DPV)-CUPric Reducing Antioxidant Capacity (CUPRAC) assay. The optimal extraction time, temperature and solvent type were 6 min, 80 °C and 80% (v/v) methanol (MeOH), respectively. Microwave-assisted extracts of herbs (Hypericum scabrum L., Papaver fugax Poiret var. platydiscus Cullen, and Achillea vermicularis Trin.) were screened for total antioxidant capacity (TAC), total phenolic content (TPC) and ROS scavenging activities by employing different in vitro spectrophotometric assays. A positive correlation was observed between TAC-CUPRAC and TPC (R 2 = 0.972). Similarly, a positive correlation was observed between TAC-CUPRAC and free radical scavenging (FRS) activity (R 2 = 0.977). The order of FRS activities of tested samples was as follows: Hypericum scabrum L. > Achillea vermicularis Trin. > Papaver fugax Poiret var. platydiscus Cullen. These results suggest that these medicinal herbs provide promising antioxidant potentials as potential natural preservative agents in pharmaceutical industries.

Quercus pyrenaica Honeydew Honey With High Phenolic Contents Cause DNA Damage, Apoptosis, and Cell Death Through Generation of Reactive Oxygen Species in Gastric Adenocarcinoma Cells

“…The samples in the auto sampler were kept at 15°C during the experiment. 14,15 LC-MS/MS experiments were performed on a Zivak Multitasker and Zivak Tandem Gold Triple quadrupole (Istanbul, Turkey) mass spectrometer equipped with a Fortis C18 column (150 × 3.0 mm id, 5 µm particle size). The mobile phase was composed of water (A, 0.1% formic acid) in water (B, 0.1% formic acid in methanol), the gradient program of which was 0 to 1.00 minute 70% A and 30% B, 1.01 to 20.00 minutes 100% B, and finally 20.01 to 25.00 minutes 70% A and 30% B.…”

Chemical Composition and Assessment of Antimicrobial, Antioxidant and Antiproliferative Activities of Essential oil from Clinopodium sericeum, a Peruvian Medicinal Plant

“…The FRAP and CUPRAC assays were carried out as previously described [19] with some modifications. Briefly, the FRAP the stock solutions included 300 mM acetate buffer pH 3.6, 10 mM TPTZ (2,4,6-tripyridyl-S-triazine) solution in 40 mM HCl, and 20 mM FeCl3 x 6H2O solution.…”

Anticholinergic and antioxidant activities of avocado (Folium perseae) leaves – phytochemical content by LC-MS/MS analysis

“…CID gas pressure of 2.40 mTorr, 5000 V ESI needle voltage, 600 V ESI (electrospray ionization) shield voltage, 300°C drying gas temperature, 50°C API housing temperature, 55 psi nebulizer gas pressure, and 40 psi drying gas pressure were determined as optimum ESI parameters. [46,47] LC-MS/MS parameters of secondary metabolites and internal standard are given in Table 1. The LODs were determined to be three times bigger than while LOQs were determined to be 10 times bigger than standard deviation (Table 2).…”

“…The validation and uncertainty evaluation procedure and the results of validation are discussed in former studies. [40,46,47]…”