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Geochemical characterization and palaeoenvironmental implications of lipids in Neogene lignites and lignitic shales in NW Poland

Czechowski Franciszek, Polowczyk Marzena, Simoneit Bernt R. T., Grelowski Cezary, Hojniak Marek

Annales Societatis Geologorum Poloniae

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2023

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Vol. 93, No. 4

447--466

EN

The lipophilic biomarker distributions in lipids of Neogene lignites and lignitic shales in western Pomerania and the midlands of Poland are presented. Twenty-six lignite samples and seven lignitic shales were obtained from twenty-four boreholes. Their extracts were separated, using thin-layer chromatography, and the saturate and aromatic fractions were analyzed by gas chromatography-mass spectrometry. The molecular compositions of n-alkanes, isoprenoids, n-alkylcyclohexanes, n-alkylbenzenes, tri- and tetracyclic diterpenoids, pentacyclic triterpenoids, as well as polycyclic aromatic hydrocarbons (PAHs) with up to five rings, were determined. The samples displayed n-alkane distributions in the range of C14–C35 and high odd-over-even carbon number predominances (CPI(25–33) from 2.9 to 7.9). Diterpanes consisted primarily of phyllocladane, abietane, isopimarane, labdane, and kaurane structures, although their abundances varied among the samples. Hopanes exhibited the biological and geochemical characteristics of low-maturity organic matter. Minor oleanane triterpenoids from angiosperms were also found. A few samples displayed evidence of biodegradation on the basis of the advanced isomerization of αβ-hopanes and the presence of short-chained n-alkanes, n-alkylcyclohexanes, and n-alkylbenzenes. A more mature stage of the above biomarkers also may have resulted in part from the oxidation of organic matter. The lignite source materials were derived from conifer and angiosperm flora as well as microbial remnants. The contribution from marine phytoplankton was excluded on the basis of the lack of C27 steroids. PAHs were predominantly perylene or phenanthrene, with minor other analogues. Thus, the data support progressive lacustrine/lagoonal sedimentation in the palaeoenvironmental mires.

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Rapid analysis and identification of the main constituents in Patrinia scabiosaefolia Fisch. by UPLC/Q-TOF-MS/MS

Zhong Y. M., Zhong X. L., Wang J. H., Han L.

Acta Chromatographica

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2017

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Vol. 29, no. 2

267--277

EN

Patrinia scabiosaefolia Fisch. (PSF), a well-known traditional Chinese medicine, has been demonstrated to show therapeutic effects on inflammatory bowel disease. In this study, a rapid and sensitive method using ultra-performance liquid chromatography/quadrupole time-of-flight mass spectrometry (UPLC/Q-TOF-MS) was developed for identification of the major constituents in PSF. The separation analysis was performed on Waters Acquity UPLC system, and the accurate mass of molecules and their fragment ions were determined by Q-TOF-MS. Thirty-one constituents, including triterpenoids, iridoids, flavonoids, and organic acids were detected and tentatively deduced on the basis of their element compositions, tandem mass spectrometry (MS/MS) data, and relevant literatures. Twelve constituents were discovered for the first time in PSF. The results demonstrated that hederagenin-type and oleanolic acid-type saponins were the main constituents of PSF. Our work provides a certain foundation for further quantitation of major chemical constituents and in vivo pharmacokinetic studies of PSF. Moreover, the analytical approach developed herein has proven to be generally applicable for profiling the chemical constituents in traditional Chinese medicines (TCMs) and other complicated mixtures.

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Two New Steroids Dehydroadynerizoside and Neristigmol from Nerium oleander Leaves

Siddiqui B., Khatoon N., Begum S., Sultana R., Durrani S.

Polish Journal of Chemistry

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2006

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Vol. 80, nr 3

445-452

EN

Two new steroids dehydroadynerizoside (1) and neristigmol (2) have been isolated from the fresh, uncrushed leaves of Nerium oleander and their structures elucidated as 3beta-O-(beta-D-2-deoxy-rhamnosyl)-8,14beta-epoxy-5beta-carda-16,20(22)-dienolide and hexyl p-stigmasteryloxy-benzoate, respectively. The structure elucidation is based on spectroscopic methods including 1D NMR (1H NMR, 13C NMR) and 2D NMR (1H-1H COSY, NOESY, HMQC, HMBC and J-resolved) and chemical transformation.

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Związki naturalne z układem gem-dimetylocykloheksanu

Grabarczyk M.

Wiadomości Chemiczne

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2004

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[Z] 58, 7-8

613--635

EN

Many natural terpenoids include in their structure a gem-dimethylcyclohexane ring. Such compounds are often isolated from plants or animals, where they fulfil different functions. Compounds a with gem-dimethylcycloxehane ring have been found in many marine algaes molluscs. These compounds show different biological properties, for example antibiotic [10, 66, 67, 79], cytotoxic [15, 16], fungicidal [17], inhibiting HIV [11]. Similar properties are also found in compounds isolated from plants growing in different places on Earth, plants which for many years have been known and used in tradicional medicine as antidote against different diseases [24-27, 36-46, 72-74]. These discoveries are very important for people searching for new and effective medicines against old and new diseases. For example some compounds with a gem-dimethylcyclohexane ring show an inhibitory effect on not yet curable cancers [50-57, 81]. The compounds with a gem-dimethylcyclohexane ring which occur in plants or animals have an affect not only on humans, but also on other plants or animals. Such affect can be observed in both marine and terrestial organisms [59-61, 71]. In our times very safe and effective crop protection is a very important problem. Because of this people try to find natural compounds which can produce desirable biological effects. Compounds with a gem-dimethylcycloxehane ring found in some plants can act as natural herbicides [22, 23]. Some of these compounds can also work as deterrents against insect pests. These deterrents affect the insects' sense of taste and prevent them from eating, which finally makes them die despite the abundance of food [28-33].

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Structure Elucidation of Saponins and Related Natural Products by NMR Spectroscopy

Duddeck H.

Polish Journal of Chemistry

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1999

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vol. 73 nr 1

163-171

EN

For a number of examples strategies are developed and explained how structures of complex natural products, such as triterpene glycosides and related compouns, can be efficiently elucidated by application of modern one- and two-dimensional NMR techniques.