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1.
Chirality ; 32(7): 998-1007, 2020 07.
Artigo em Inglês | MEDLINE | ID: mdl-32250002

RESUMO

(R)-ricinoleic acid is the main component of castor oil from Ricinus communis L. Due to the presence of the hydroxyl group in homoallylic position and asymmetrically substituted carbon atom, it may undergo a number of chemical and biochemical transformations resulting in the products with some specific bioactivities. Conversion of (R)-ricinoleic acid into its (S)-enantiomer enables synthesis of both (R)- and (S)-ricinoleic acid derivatives and comparison of their biological activities. In the present research, (R)- and (S)-ricinoleic acid amides synthesized from methyl ricinoleates and ethanolamine or pyrrolidine as well as acetate derivatives of ethanolamine amides were studied to demonstrate their biological activities using HT29 cancer cells. Double staining of cells with fluorochromes (Hoechst 33258/propidium iodide) as well as 2,'7'-dichlorodihydrofluorescein (DCF) and comet assays were performed. Both the tested amides and acetates caused DNA damage and induced apoptotic and necrotic cell death. In the case of (R)- and (S)-enantiomers of one of the tested acetates, significant difference in the ability to induce DNA damage was observed, which showed the impact of the stereogenic center on the activities of these compounds.


Assuntos
Acetatos/química , Amidas/química , Antineoplásicos/farmacologia , Óleo de Rícino/química , Ácidos Ricinoleicos/química , Antineoplásicos/química , Dano ao DNA/efeitos dos fármacos , Células HT29 , Humanos , Ácidos Ricinoleicos/toxicidade , Estereoisomerismo
2.
Food Chem ; 301: 125283, 2019 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-31377615

RESUMO

A small library of 57 low molecular weight oximes was prepared from fragrant aldehydes and ketones, and their olfactory profiles were determined. The most substantive and interesting in terms of the sensory impressions were (+)-isomenthone oxime (fresh, musty, green) and cyclocitral oxime (earthy with patchouli, moss and leather notes). The linear retention indices (LRI) were determined for DB-1, DB-5 and DB-WAX columns, and E/Z isomers of 22 out of 57 compounds were resolved on the DB-5 column. Attempts were made to resolve enantiomers of the chosen oximes on chiral GC columns. The best results were obtained by using a Cyclosil B column, on which the enantiomers of camphor, menthone, piperitone and carvone oximes were fully resolved. NMR and MS spectra were acquired to characterize the synthesized library. Gas chromatography-olfactometry was used to assess odoriferous properties of both isomers of oximes. In most cases both isomers possessed similar profile and intensity.


Assuntos
Óleos Voláteis/química , Oximas/análise , Cromatografia Gasosa , Odorantes/análise , Olfatometria , Oximas/química , Estereoisomerismo , Compostos Orgânicos Voláteis/análise
3.
Chirality ; 29(10): 616-622, 2017 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-28771822

RESUMO

An environment-friendly, free of solvent, process for the synthesis of (R)- and (S)-ricinoleic acid amides has been developed. Starting from methyl ricinoleates and pyrrolidine or ethanolamine, the corresponding amides were obtained with yields ranging from 83-88%. Among 12 synthesized derivatives of ricinoleic acid, including the starting methyl esters, amides, and their acetates, nine compounds were obtained and tested for the first time. Studies on ricinoleic acid derivatives cytotoxicity showed that methyl esters were the least cytotoxic compounds and modification of their structure resulted in increasing cytotoxicity of the obtained products against both cancer cells and normal lymphocytes. Both enantiomers of the ethanolamine-derived amides showed the most promising anticancer potential.


Assuntos
Acetatos/química , Amidas/química , Antineoplásicos/síntese química , Antineoplásicos/farmacologia , Ácidos Ricinoleicos/síntese química , Ácidos Ricinoleicos/farmacologia , Antineoplásicos/química , Linhagem Celular Tumoral , Técnicas de Química Sintética , Humanos , Ácidos Ricinoleicos/química , Estereoisomerismo
4.
J Sci Food Agric ; 97(11): 3576-3583, 2017 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-28098355

RESUMO

BACKGROUND: Large quantities of blackberry seeds are produced as a pomace during the processing of juice and jam production; this by-product is a very interesting raw material both for oil manufacturing and as a source of bioactive compounds. In this work the composition, yield and antioxidant activity of three types of Rubus fructicosus pomace extracts isolated by liquid extraction using solvents of different polarity, as well with supercritical CO2 fluid extraction have been compared. RESULTS: The highest extract yield was reported for Soxhlet extraction using ethanol as a solvent (14.2%). Supercritical carbon dioxide and hexane extracts were characterised by the highest content of phytosterols (1445 and 1583 mg 100 g-1 of extract, respectively) among which ß-sitosterol was the main one, while the concentration of tocopherols, with predominant γ-isomer, was the highest for both hexane and ethanol extracts, being 2364 and 2334 mg 100 g-1 , respectively. Using a GC-MS method 95 volatiles, in which non-saturated aldehydes were predominant, were identified in the essential oil of seed pomace and in the volatile oil isolated from supercritical extract. The ethanolic extract which is characterised by the highest phenolic content (9443 mg GAE 100 g-1 ) exhibited the highest antioxidant activity (according to the ABTS•+ and DPPH• assays). CONCLUSION: All pomace extracts examined were of high quality, rich in essential omega fatty acids and with a very high content of bioactive compounds, such as phytosterols and tocopherols. The high nutritional value of extracts from berry seed pomace could justify the commercialisation of specific extracts not only as food additives but also as cosmetic components. © 2017 Society of Chemical Industry.


Assuntos
Antioxidantes/química , Cromatografia com Fluido Supercrítico/métodos , Extratos Vegetais/química , Rubus/química , Antioxidantes/isolamento & purificação , Dióxido de Carbono/química , Cromatografia com Fluido Supercrítico/instrumentação , Etanol/química , Frutas/química , Hexanos/química , Extratos Vegetais/isolamento & purificação , Polônia , Rubus/crescimento & desenvolvimento
5.
Curr Med Chem ; 23(35): 4037-4056, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27356539

RESUMO

(R)-Ricinoleic acid (RA) [(12R,9Z)-hydroxyoctadecenoic acid], the main compound of castor seed oil, because of its unusual structure readily undergoes multi-directional chemical and biochemical transformations to produce derivatives with the retained carbon skeleton or with its degradation. Many of these are of high biological activity, as documented by an in vitro study, and possess therapeutic potential. This review article provides an overview of the recent developments in the area of synthesis of RA based compounds with anticancer and antimicrobial activities. Moreover, the antiinflammatory and analgesic properties of some ricinoleic acid derivatives are also highlighted.


Assuntos
Anti-Infecciosos/síntese química , Ácidos Ricinoleicos/química , Anti-Infecciosos/metabolismo , Anti-Infecciosos/farmacologia , Antineoplásicos/síntese química , Antineoplásicos/química , Antineoplásicos/metabolismo , Antineoplásicos/farmacologia , Apoptose/efeitos dos fármacos , Óleo de Rícino/química , Humanos , Poliésteres/química , Ácidos Ricinoleicos/síntese química , Ácidos Ricinoleicos/metabolismo , Ácidos Ricinoleicos/farmacologia , Bases de Schiff/química , Staphylococcus aureus/efeitos dos fármacos , Estereoisomerismo
6.
Chem Phys Lipids ; 183: 137-41, 2014 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-24956018

RESUMO

(R)-ricinoleic acid methyl ester obtained from commercial castor oil was transformed in a three-step procedure into its S-enantiomer in overall 36% yield using ionic liquid (1-butyl-3-methylimidazolium acetate) in the key step process. The developed procedure provides easy access to (S)-ricinoleic acid and its methyl ester of over 95% enantiomeric excess. Optical rotations of the newly obtained compounds as well as their chromatographic and spectral characteristics are provided and discussed in the context of enantiopurity both of the substrate material and the final products.


Assuntos
Óleo de Rícino/química , Líquidos Iônicos/química , Ácidos Ricinoleicos/síntese química , Ácidos Ricinoleicos/isolamento & purificação , Esterificação , Ésteres , Metilação , Estereoisomerismo
7.
Plast Reconstr Surg ; 115(1): 128-33, 2005 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-15622242

RESUMO

The aim of this article was to show the participation of epidermal growth factor (EGF) in the pathogenesis of Dupuytren's disease (palmar contracture). The concentration of EGF in specimens obtained from 68 patients with Dupuytren's contracture and 14 controls was examined immunochemically with the use of enzyme-linked immunosorbent assay. The determined EGF concentration in pathologic aponeurosis with symptoms of Dupuytren's disease (median, 6.29 ng/g; range, 1.67 to 63.09 ng/g) showed significantly different values (p = 0.036) in comparison with the control group (median, 10.1 ng/g; range, 5.13 to 39.81 ng/g). The changes in EGF concentration were shown in tested groups of pathologic tissues that were formed according to the clinical stage of disease progression. The significantly lower concentration than that seen in the control group characterizes tissues with first and third degrees of palmar contracture progression (p = 0.025 and p = 0.018, respectively). In the group of patients with second-degree disease progression, the EGF level increased transiently. Nevertheless, in comparison with the other groups, the difference was not significant. The group with the fourth degree of the disease showed EGF concentrations that resembled the control values. The authors conclude that significant differences in levels of EGF concentration between contractured and normal fasciae may suggest the participation of this cytokine in the pathogenesis of Dupuytren's disease.


Assuntos
Contratura de Dupuytren/etiologia , Fator de Crescimento Epidérmico/análise , Idoso , Progressão da Doença , Contratura de Dupuytren/metabolismo , Contratura de Dupuytren/patologia , Fator de Crescimento Epidérmico/deficiência , Fáscia/química , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Fumar/efeitos adversos
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