Cones of coniferous taxa as a potential source of bioactive polyphenols

Background: Coniferous cones are a by-product of forestry and wood logging, used for many possible purposes, e.g., the extraction of polyphenols. Objective: The aim of the present article was the comparison of the antioxidant polyphenol content of the differently matured cones of 17 selected conifers, either common in Hungary or yet uninvestigated. Methods: Total polyphenol content, ferric reducing antioxidant power and 2,2-diphenyl-1-picrylhydrazyl assays were used to determine the antioxidant contents. A scoring system was implemented using the three assay results to evaluate and compare the overall antioxidant power of the samples. Result and Conclusion: Highest antioxidant contents were found in green cones, followed by mature and opened cones. Taxa with the highest scores were Tsuga canadensis, Cryptomeria japonica, Chamaecyparis lawsoniana, Thuja orientalis, Metasequoia glyptostroboides and Picea abies. For the samples with the highest overall antioxidant power the high-performance liquid chromatographic/tandem mass spectrometric polyphenol profiling was carried out (green cones of T. canadensis and P. abies) and 83 compounds have been tentatively identified and described. Results contribute to the future bioactivity testing and evaluation of the cone extracts of T. canadensis and P. abies.

Comparison of Two Immunoassay Screening Methods and a LC-MS/MS in Detecting Traditional and Designer Benzodiazepines in Urine

Sensitive and specific immunoassay screening methods for the detection of benzodiazepines in urine represent an important prerequisite for routine analysis in clinical and forensic toxicology. Moreover, emerging designer benzodiazepines force labs to keep their methodologies updated, in order to evaluate the reliability of the immunochemical techniques. This study aimed at evaluating the sensitivity and specificity of two different immunoassay methods for the detection of benzodiazepines in urine, through a comparison with the results obtained by a newly developed liquid chromatographic tandem mass spectrometric (LC-MS/MS) procedure. A cohort of authentic urine samples (N = 501) were processed, before and after a hydrolysis procedure, through two immunoassays and an LC-MS/MS method. The LC-MS/MS target procedure was optimized for monitoring 25 different molecules, among traditional and designer benzodiazepines, including some metabolites. At least one of the monitored substances was detected in 100 out of the 501 samples. A good specificity was observed for the two immunoassays (>0.99), independently of the cut-offs and the sample hydrolysis. The new kit demonstrated a fairly higher sensitivity, always higher than 0.90; in particular, a high cross-reactivity of the new immunoassay was observed for samples that tested positive for lorazepam and 7-aminoclonazepam. The two immunoassays appeared adequate to monitor not only traditional benzodiazepines but also new designer ones.

Liquid Chromatography Tandem Mass Spectrometric Analytical Method for Study of Colchicine in Rats Given Low Doses

A selective and sensitive assay was developed for colchicine in rat specimens. Colchicine and its deuterated analog (as internal standard, IS) were extracted from rat specimens (minimal 0.1 mL plasma, whole blood, or urine) using liquid-liquid extraction with n-hexane:dichloromethane:isopropanol. The mobile phase (formic acid: ammonium acetate: methanol) was pumped with uniform flow through an octadecylsilane analytical column. Detection was carried out by electrospray positive ionization in the multiple-reaction monitoring mode. The assay (total run time <3 min) had excellent linearity over a wide (400–800-fold) concentration range. The mean absolute recovery was >96.8%. The intra- and inter-day coefficients of variation were ˂15%, with lower limits of quantitation of 0.5 ng/mL in 0.1 mL of rat plasma. The method also provided the same lower limits of quantitation in urine and whole blood with 0.1 mL volumes, and 0.1 ng/mL using 0.5 mL of rat plasma. The blood-to-plasma ratio was >1. Rats had measurable colchicine blood concentrations for at least 24 h after intravenous doses of 0.1 mg/kg. The method possessed suitable measures of sensitivity and selectivity for detecting colchicine in several specimen types in rats given low doses.