scholarly journals Synthesis, chemical characterization, and µ-opioid receptor activity assessment  of the emerging group of ‘nitazene’ 2-benzylbenzimidazole synthetic  opioids             

2021 ◽  
Author(s):  
Marthe Vandeputte ◽  
Katleen Van Uytfanghe ◽  
Nathan Layle ◽  
Danielle St. Germaine ◽  
Donna Iula ◽  
...  
Keyword(s):  
Opioid Receptor ◽  
High Performance ◽  
Chemical Characterization ◽  
Analytical Framework ◽  
Flight Mass Spectrometry ◽  
Highly Active ◽  
Activity Assessment ◽  
Array Detection ◽  
Very High

Several 2-benzylbenzimidazole opioids (also referred to as ‘nitazenes’) recently emerged on the illicit market. The most frequently encountered member, isotonitazene, has been identified in multiple fatalities since its appearance in 2019. Although recent scheduling efforts targeted isotonitazene, many other analogues remain unregulated. Being structurally unrelated to fentanyl, little is known about the harm potential of these compounds. In this study, ten nitazenes and four metabolites were synthesized, analytically characterized via four different techniques, and pharmacologically evaluated using two cell-based β-arrestin2/mini-Gi recruitment assays monitoring µ-opioid receptor (MOR) activation. Based on absorption spectra and retention times, high-performance liquid chromatography coupled to diode-array detection (HPLC-DAD) allowed differentiation between most analogues. Time-of-flight mass spectrometry (LC-QTOF-MS) identified a fragment with m/z 100.11 for 12/14 compounds, which could serve as a basis for MS-based nitazene screening. MOR activity determination confirmed that nitazenes are generally highly active, with potencies and efficacies of several analogues exceeding that of fentanyl. Particularly relevant is the unexpected very high potency of the N-desethyl-isotonitazene metabolite, rivalling the potency of etonitazene and exceeding that of isotonitazene itself. Supported by its identification in fatalities, this likely has in vivo consequences. These results improve our understanding of this emerging group of opioids by laying out an analytical framework for their detection, as well as providing important new insights into their MOR activation potential.

Analysis of Polyphenols Composition and Antioxidant Activity Assessment of Chinese Dwarf Cherry (Cerasus humilis (Bge.) Sok.)

2019 ◽  
Vol 14 (6) ◽  
pp. 1934578X1985650 ◽  
Author(s):  
Qian Wu ◽  
Ru-Yu Yuan ◽  
Cheng-Yong Feng ◽  
Shan-Shan Li ◽  
Liang-Sheng Wang
Keyword(s):  
High Performance ◽  
Antioxidant Activities ◽  
Chemical Mechanism ◽  
Liaoning Province ◽  
Photodiode Array Detection ◽  
Flight Mass Spectrometry ◽  
Activity Assessment ◽  
Cerasus Humilis ◽  
Photodiode Array ◽  
Array Detection

The fruits of Chinese dwarf cherry ( Cerasus humilis (Bge.) Sok.), which is unique to China, can be canned and used to make products such as jam and wine. They also contain abundant bioactive compounds, including cinnamoylquinic acids and flavonoids. However, there has been no systematic study on the functional compounds in these fruits. In this study, the polyphenol compounds of 28 different genotypes of Chinese dwarf cherry in Liaoning province were systematically characterized using high-performance liquid chromatography with photodiode array detection and HPLC coupled with quadrupole time-of-flight mass spectrometry. A total of 31 polyphenols, including 6 anthocyanins, 7 cinnamoylquinic acids, 1 flavone, and 17 flavonols, were identified, and 23 of these compounds were detected in Chinese dwarf cherry for the first time. In addition, 4 genotypes showed higher total polyphenol content and antioxidant activities. It may be advantageous to use these 4 genotypes for commercial processing of Chinese dwarf cherry fruits into healthcare products. The results of this study will improve understanding of the chemical mechanism of polyphenols formation and lay the foundation for selective functional composition breeding in Chinese dwarf cherry.

scholarly journals Identification and Content of Astaxanthin and Its Esters from Microalgae Haematococcus pluvialis by HPLC-DAD and LC-QTOF-MS after Extraction with Various Solvents

Plants ◽  
2021 ◽  
Vol 10 (11) ◽  
pp. 2413
Author(s):  
Biljana Todorović ◽  
Veno Jaša Grujić ◽  
Andreja Urbanek Krajnc ◽  
Roman Kranvogl ◽  
Jana Ambrožič-Dolinšek
Keyword(s):  
High Performance ◽  
Haematococcus Pluvialis ◽  
Methyl Tert Butyl Ether ◽  
Diode Array ◽  
Diode Array Detection ◽  
Butyl Ether ◽  
Flight Mass Spectrometry ◽  
Green Microalga ◽  
Array Detection ◽  
Long Chain

Haematococcus pluvialis, a unicellular green microalga that produces a secondary metabolite under stress conditions, bears one of the most potent antioxidants, namely xanthophyll astaxanthin. The aim of our study was to determine the content of astaxanthin and its esterified forms using three different solvents—methyl tert-butyl ether (MTBE), hexane isopropanol (HEX -IPA) and acetone (ACE)—and to identify them by using high performance liquid chromatography coupled with diode array detection and the quadrupole time-of-flight mass spectrometry (HPLC-DAD and LC-QTOF-MS) technique. We identified eleven astaxanthin monoesters, which accounted for 78.8% of the total astaxanthin pool, six astaxanthin diesters (20.5% of total), while free astaxanthin represented the smallest fraction (0.7%). Astaxanthin monoesters (C16:2, C16:1, C16:0), which were the major bioactive compounds in the H. pluvialis samples studied, ranged from 10.2 to 11.8 mg g−1 DW. Astaxanthin diesters (C18:4/C18:3, C18:1/C18:3) were detected in the range between 2.3 and 2.6 mg g−1 DW. All three solvents were found to be effective for extraction, but MTBE and hexane-isopropanol extracted the greatest amount of free bioactive astaxanthin. Furthermore, MTBE extracted more low-chain astaxanthin monoesters (C16), and hexane-isopropanol extracted more long-chain monoesters (C18 and above) and more diesters. We can conclude that MTBE is the solvent of choice for the extraction of monoesters and hexane-isopropanol for diesters.

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