scholarly journals Patterns of Variation and Chemosystematic Significance of Phenolic Compounds in the Genus Cyclopia (Fabaceae, Podalyrieae)

Molecules ◽  
2019 ◽  
Vol 24 (13) ◽  
pp. 2352
Author(s):  
Maria. A. Stander ◽  
Herman Redelinghuys ◽  
Keabetswe Masike ◽  
Helen Long ◽  
Ben-Erik Van Wyk
Keyword(s):  
Mass Spectrometry ◽  
Liquid Chromatography ◽  
Phenolic Compounds ◽  
High Resolution Mass Spectrometry ◽  
Species Level ◽  
Large Dataset ◽  
Plant Parts ◽  
Negative Mode ◽  
First Time ◽  
Resolution Mass

As a contribution towards a better understanding of phenolic variation in the genus Cyclopia (honeybush tea), a collection of 82 samples from 15 of the 23 known species was analysed using liquid-chromatography–high resolution mass spectrometry (UPLC-HRMS) in electrospray ionization (ESI) negative mode. Mangiferin and isomangiferin were found to be the main compounds detected in most samples, with the exception of C. bowiena and C. buxifolia where none of these compounds were detected. These xanthones were found to be absent from the seeds and also illustrated consistent differences between species and provenances. Results for contemporary samples agreed closely with those based on analysis of a collection of ca. 30-year-old samples. The use of multivariate tools allowed for graphical visualizations of the patterns of variation as well as the levels of the main phenolic compounds. Exclusion of mangiferin and citric acid from the data was found to give better visual separation between species. The use of UPLC-HRMS generated a large dataset that allowed for comparisons between species, provenances and plant parts (leaves, pods, flowers and seeds). Phenetic analyses resulted in groupings of samples that were partly congruent with species but not with morphological groupings within the genus. Although different provenances of the same species were sometimes found to be very variable, Principle Component Analysis (PCA) indicated that a combination of compounds have some (albeit limited) potential as diagnostic characters at species level. 74 Phenolic compounds are presented, many of which were identified for the first time in Cyclopia species, with nine of these being responsible for the separation between samples in the PCAs.

scholarly journals Quantification for non-targeted LC/MS screening without standard substances

2020 ◽  
Vol 10 (1) ◽  
Author(s):  
Jaanus Liigand ◽  
Tingting Wang ◽  
Joshua Kellogg ◽  
Jørn Smedsgaard ◽  
Nadja Cech ◽  
...  
Keyword(s):  
Mass Spectrometry ◽  
Liquid Chromatography ◽  
High Resolution ◽  
High Resolution Mass Spectrometry ◽  
Random Forest Regression ◽  
Negative Mode ◽  
Regression Approach ◽  
Cereal Samples ◽  
Resolution Mass ◽  
Concentration Prediction

AbstractNon-targeted and suspect analyses with liquid chromatography/electrospray/high-resolution mass spectrometry (LC/ESI/HRMS) are gaining importance as they enable identification of hundreds or even thousands of compounds in a single sample. Here, we present an approach to address the challenge to quantify compounds identified from LC/HRMS data without authentic standards. The approach uses random forest regression to predict the response of the compounds in ESI/HRMS with a mean error of 2.2 and 2.0 times for ESI positive and negative mode, respectively. We observe that the predicted responses can be transferred between different instruments via a regression approach. Furthermore, we applied the predicted responses to estimate the concentration of the compounds without the standard substances. The approach was validated by quantifying pesticides and mycotoxins in six different cereal samples. For applicability, the accuracy of the concentration prediction needs to be compatible with the effect (e.g. toxicology) predictions. We achieved the average quantification error of 5.4 times, which is well compatible with the accuracy of the toxicology predictions.

scholarly journals New Phenolic Compounds in Posidonia oceanica Seagrass: A Comprehensive Array Using High Resolution Mass Spectrometry

Plants ◽  
2021 ◽  
Vol 10 (5) ◽  
pp. 864
Author(s):  
Marina Astudillo-Pascual ◽  
Irene Domínguez ◽  
Pedro A. Aguilera ◽  
Antonia Garrido Frenich
Keyword(s):  
Mass Spectrometry ◽  
Phenolic Compounds ◽  
High Resolution ◽  
Detection Method ◽  
High Resolution Mass Spectrometry ◽  
Posidonia Oceanica ◽  
High Resolution Mass ◽  
First Time ◽  
Different Tissues ◽  
Resolution Mass

The studies on the Posidonia oceanica Delile (P. oceanica) phenolic composition have been focused on the foliar tissues and have often neglected the phenolic compounds in rhizomes or roots alike. With the current improvements in high resolution mass spectrometry (HRMS) analyzers, such as the Orbitrap MS, there is a new opportunity to more deeply study P. oceanica. One of the benefits is the possibility of conducting an exhaustive phenolic monitoring, which is crucial in the search for new stressor-specific biomarkers of coastal deterioration. For this purpose, the different tissues (leaf, rhizome, and root) of P. oceanica seagrass from several marine sampling areas were analyzed through target, suspected, and non-target screenings. This paper brings a fast and tissues-specific extraction, as well as a detection method of phenolic compounds applying for the first time the potential of HRMS (Exactive Orbitrap) in P. oceanica samples. As a result, 42 phenolic compounds were satisfactorily detected, of which, to our knowledge, 24 were not previously reported in P. oceanica, such as naringenin, naringenin chalcone and pinocembrin, among others. Information here reported could be used for the evaluation of new stressor-specific biomarkers of coastal deterioration in the Mediterranean waters. Furthermore, the followed extraction and analytical method could be considered as a reference protocol in other studies on marine seagrasses due to the exhaustive search and satisfactory results.

scholarly journals Liquid chromatography – high resolution mass spectrometry screening of Astragalus hamosus and Astragalus corniculatus

Pharmacia ◽  
2021 ◽  
Vol 68 (1) ◽  
pp. 135-139
Author(s):  
Aleksandar Shkondrov ◽  
Ilina Krasteva
Keyword(s):  
Mass Spectrometry ◽  
High Performance Liquid Chromatography ◽  
Liquid Chromatography ◽  
High Resolution ◽  
High Performance ◽  
High Resolution Mass Spectrometry ◽  
Ionisation Mass Spectrometry ◽  
First Time ◽  
Ionisation Mass ◽  
Resolution Mass

Astragalus hamosus and Astragalus corniculatus were examined for the presence of flavoalkaloids, acylated and highly glycosylated flavonoids. Non-purified extracts of the overground parts of the species were subjected to ultra-high performance liquid chromatography – high resolution electrospray ionisation mass spectrometry (UHPLC-HRESIMS) analysis and the results were compared to authentic reference substances. A flavoalkaloid of kaempferol was newly identified in an extract of A. hamosus. In addition, three compounds – quercetin and kaempferol flavonoids, acylated with hydroxymethylglutaric acid and alcesefoliside, were found in extracts of A. hamosus and A. corniculatus for the first time.

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