Phytochemical profile and some biological activities of three Centaurea species from Turkey

Purpose: To characterise the phytochemical profile of whole plants of Centaurea balsamita, C. depressa and C. lycopifolia with LC-ESI-MS/MS, and as well as their antioxidant, anticholinesterase and antimicrobial activities.Methods: Organic and aqueous extracts of the three Centaurea species were evaluated for DPPH free radical, ABTS cation radical scavenging and cupric reducing antioxidant capacity (CUPRAC). Acetyland butyryl-cholinesterase enzyme inhibition abilities of the extracts using petroleum ether, acetone, methanol and water were studied to determine anticholinesterase activity, while antimicrobial activity was determined by disc diffusion method using appropriate antimicrobial standards and organisms. The phytochemical components of the methanol extracts were assessed by LC-MS/MS.Results: The methanol extract of C. balsamita exhibited much higher DPPH free and ABTS cation radicals scavenging activities (with IC50 of 62.65 ± 0.97 and 24.21 ± 0.70 mg/ml, respectively) than the other extracts. The petroleum ether extracts of the plant species exhibited moderate inhibitory activity against butyrylcholinesterase enzymes while the acetone extract of C. balsamita showed good antifungal activity against Candida albicans. Quinic acid (17513 ± 813 μg/g, 63874 ± 3066 μg/g and 108234 ± 5195 μg/g) was the major compound found in the methanol extracts of C. balsamita, C. depressa and C. Lycopifolia, respectively.Conclusion: These results indicate quinic acid is the major compound in the three plant species and that Centaurea balsamita has significant antioxidant, anticholinesterase and antimicrobial properties. Further studies to identify the compounds in the extracts responsible for the activities are required.Keywords: Centaurea, LC-ESI-MS/MS, Anticholinesterase, Antioxidant, Antimicrobia

New diterpenoids from the aerial parts of Salvia pilifera

Three new diterpenoids, piliferol (2 alpha,20-dihydroxy-12-oxo-abieta-9(11),13-dien-8,20-ether) (1), salvipiliferol (2 alpha,10 beta-dihydroxy-12-oxo-norabieta-9(11) 13-dien) (2), and piliferalactone (2 alpha,8-dihydroxy-12-oxo-abieta-9(11),13-dien-20-oic acid-8,20-lactone) (3), together with 7 known compounds, ursolic acid, oleanolic acid, betulinic acid, alpha-amyrin, lnpeol, beta-sitosterol, and pectolinarigenin, have been isolated from the aerial parts of an endemic Salvia species, S. pilifera. Their structures were elucidated by spectral (UV, IR, 1D-, and 2D-NMR, and HRMS) methods

Determination of Phenolic Acids in Atriplex hortensis L. by Novel Solid-Phase Extraction and High-Performance Liquid Chromatography

A novel offline solid-phase extraction high-performance liquid chromatography method is reported for the determination of phenolic acids in Atriplex hortensis L. Isolation of the analytes was performed by maceration followed by solid-phase extraction with hydrophilic-lipophilic balance cartridges. The chromatography was performed using C18 guard and analytical columns. The mobile phase was 0.08%, aqueous o-phosphoric acid and 40: 60 water/acetonitrile with gradient eluation. The analytes were detected at 254 nm by an ultraviolet detector. Calibration equations were obtained by least squares with a linear dynamic range from 1.00 to 20.00 mg/L. The limits of detection and quantification were from 0.25 to 0.45 and 0.77 to 1.36 mg/L, respectively. The precision was characterized as the repeatability and intermediate precision with samples fortified at low, medium, and high concentrations. The accuracy was evaluated as the recovery. The developed method determined the presence of vanillic acid, syringic acid, and ferulic acid in A. hortensis with good accuracy and precision

Method Validation for the Quantitative Analysis of Aflatoxins (B1, B2, G1, and G2) and Ochratoxin A in Processed Cereal-Based Foods by HPLC with Fluorescence Detection

Modified AOAC 991.31 and AOAC 2000.03 methods for the simultaneous determination of total aflatoxins (AFs), aflatoxin B1, and ochratoxin A (OTA) in processed cereal-based foods by RP-HPLC coupled with fluorescence detection were validated. A KOBRA (R) Cell derivatization system was used to analyze total AFs. One of the modifications was the extraction procedure of mycotoxins. Both AFs and OTA were extracted with methanol water (75 + 25, v/v) and purified with an immunoaffinity column before HPLC analysis. The modified methods were validated by measuring the specificity, selectivity, linearity, sensitivity, accuracy, repeatability, reproducibility, recovery, LOD, and LOQ parameters. The validated methods were successfully applied for the simultaneous determination of mycotoxins in 81 processed cereal-based foods purchased in Turkey. These rapid, sensitive, simple, and validated methods are suitable for the simultaneous determination of AFs and OTA in the processed cereal-based foods