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1

Występowanie kwasów tłuszczowych i steroli w środowisku naturalnym

Łobos-Moysa E., Dudziak M.

Proceedings of ECOpole

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2016

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Vol. 10, No. 1

209--217

PL

Postęp w rozwoju technik analitycznych umożliwia obecnie oznaczanie bardzo dużej liczby zanieczyszczeń organicznych występujących w środowisku naturalnym. Część tych zanieczyszczeń jest pochodzenia naturalnego. Aktualnie badania ukierunkowane są głównie na zanieczyszczenia specyficzne, których obecność jest wynikiem antropogenicznego oddziaływania na środowisko naturalne. W celu oceny występowania specyficznych zanieczyszczeń i mikrozanieczyszczeń w środowisku naturalnym, tj. wybranych kwasów tłuszczowych nienasyconych - oleinowego i linolowego oraz kwasu nasyconego - palmitynowego, a także steroli stigmasterolu i β-sitosterolu oraz betuliny, opracowano techniki ich wydzielania i ich chromatograficznej analizy. Analizę jakościowo-ilościową zarówno kwasów tłuszczowych, jak i steroli wykonywano przy użyciu chromatografu GC / ion trap / MS (model Saturn 2100 T firmy Varian) wyposażonego w kolumnę chromatograficzną VF-5ms (Varian). Do wydzielania związków zastosowano różne techniki ekstrakcji. W przedstawionych w pracy badaniach prowadzono monitoring występowania zanieczyszczeń w wodach powierzchniowych Górnego Śląska (Wójtowianka (Doa), Potok Rokitnicki, rzeka Bytomka, rzeka Kłodnica i Kanał Gliwicki) w okresie od stycznia do czerwca 2015 roku.

EN

Nowadays, advances in the analytical techniques allow the determination of hundreds of organic pollutants present in the environment. Some of organic pollutants are of natural origin. Although the current study are mainly aimed at specific pollution, the presence of which is the result of anthropogenic impacts on the environment. In order to assess the appearance of specific pollutants and micropollutants in the environment ie the selected unsaturated fatty acids: oleic, linoleic, saturated acid: palmitic and sterols: stigmasterol, β-sitosterol and betulin, the techniques for their isolation and analysis have been developed. Quality and quantity analysis of fatty acids and sterols was carried out using GC/ion trap/MS chromatographic system (model Saturn 2100 T, Varian) equipped with a chromatography column VF-5ms (Varian). Various extraction techniques have been used for isolation of the pollutants. In this study the monitoring of level of contamination in surface water of Upper Silesia (Wójtowianka (Doa) Stream, Rokitnica Stream, Bytomka River, Klodnica River and Gliwice Channel) was conducted in the period from January to June in the 2015.

2

Wpływ fosfatydylobetulin na bakterie Staphylococcus aureus

Malicki A., Tubek-Barycza B., Janik P., Szpak M., Źródłowska-Danek J., Grabowski T., Szyplik K., Wawrzeńczyk C.

Przemysł Chemiczny

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2013

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T. 92, nr 8

1532-1537

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Synteza i aktywność cytotoksyczna estrów betuliny i kwasu betulinowego z kwasami terpenowymi

Barycza B., Pawlak A., Poradowski D., Obmińska-Mrukowicz B., Wawrzeńczyk C.

Przemysł Chemiczny

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2013

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T. 92, nr 5

806-812

4

Betulina triterpen pentacykliczny

Achrem-Achremowicz J., Janeczko Z.

Wiadomości Chemiczne

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2003

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[Z] 57, 3-4

223--246

EN

Triterpenes are the group of natural compounds widespread in the plant kingdom. They exhibit a range of biological activities. One of the most explored structures alike is betulin. This is a lupane type triterpene which is the main constituent of the extract of the white birch bark. Betulin moiety is composed of four six- and one five membered rings with one isopropenyl and two hydroxyl groups (1). Betulin and its derivatives show: antitumor , antiviral (HIV-1), antiinflammatory and antiprotosoal properties. The most promising, however, is antitumor activity. Betulinic acid - a product of the selective oxidation of betulin displays proapoptotic activity against several highly resistant tumor cells in vitro and in vivo. Apoptosis i.e. cell-suicide is induced only in "mutant" cells and not in normal ones. EC50 (effective concentration causing death of 50% of the ill cells) of betulinic acid and its derivatives lie in the pM range. Isolation, biogenesis and preparation of several modified betulin derivatives are reviewed in this article. Among the described reactions are: several routes of selective oxidation of betulin, dehydration, isomerisation, dehydrogenation, hydrogenation, glycosidation, esterification, preparation of amides (with the use of aminoacides) and synthesis of aminoderivatives. Some of these reactions give unexpected products. The biological potency of these compounds may be due to their steroid-like structures (all-trans conformation and some more similarities). The exact mechanisms of the activities, however, remain unknown. The ease of obtaining highly pure betulin and the potent biological activity of its derivatives can be the reason for singling out the compound as a lead, model triterpene for further chemical and biological investigations.

5

Alkohol betulinowy i jego pochodne

Tomaszkiewicz-Potępa A., Piękoś M.

Wiadomości Chemiczne

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2002

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[Z] 56, 11-12

983-1001

EN

Betulinic alkohol (lup-20(29)-en-3,28-diol) is a naturally occuring triterpene compound forming the principal extractive substance of the birch bark. The content of betulinol in the outer bark varies between 10-30% depending on the growth condition, age, season etc. Chemically, betulinol is a pentacyclic triterpene alcohol belonging to a lupane series of compouds. The characteristic feature of the lupane group is the five membered ring E and a-isopropyl group at C-19. Suberin and triterpenoids, the two major component groups in the outer bark of birch, have been investigated by many workers. Analytical procedures, starting with sample extraction and hydrolysis with ethanolic alkali, were developed for routine analysis, which triterpenoids to be identified by the chromatographic and spectroscopic methods. The functional groups in the betulinol molecule comprise primary and secondary hydroxyl groups and a double bond. Methods of synthesis and use of the chemical modification of betulinol has been investigated by many workers. The most investigated products from betulinol now are betulinic acid and his derivatives. It was isolated for the first time from many of plants. Betulin was convert to betulinic acid using two different synthetic routes. The first approach involved an oxidation of betulin using Jones reagent to betulonic acid and subsequent NaBH4 reduction to betulinic acid. The second approach involved steps utilizing different protecting groups on the alcohol functional groups of betulin and Jones’ oxidation to circumvent the isomerization of the secondary alcohol of betulinic acid. Betulinic acid was identified as a highly selective inhibitor of human melanoma. It has recently been reported to possess antitumor activity against cultured human melanoma cells. Betulinic acid has been modified at C-3, C-20 and C-28 positions. A series of w-undecanoic amides of betulinic acid derivatives were synthesized and evaluated for activity in human immunodeficiency virus type 1 (HIV-1). A novel series of w - aminoalkanoic acid derivatives of betulinic acid were synthesized and evaluated for their activity against human immunodeficiency virus (HIV). Effect of betulinic acid and radiotherapy on survival was demonstrated by autors.