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1.
Front Microbiol ; 14: 1223123, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37434714

RESUMO

Propenylbenzenes, including isosafrole, anethole, isoeugenol, and their derivatives, are natural compounds found in essential oils from various plants. Compounds of this group are important and valuable, and are used in the flavour and fragrance industries as well as the pharmaceutical and cosmetic industries. The aim of this study was to develop an efficient process for synthesising oxygenated derivatives of these compounds and evaluate their potential biological activities. In this paper, we propose a two-step chemo-enzymatic method. The first step involves the synthesis of corresponding diols 1b-5b from propenylbenzenes 1a-5avia lipase catalysed epoxidation followed by epoxide hydrolysis. The second step involves the microbial oxidation of a diasteroisomeric mixture of diols 1b-5b to yield the corresponding hydroxy ketones 1c-4c, which in this study was performed on a preparative scale using Dietzia sp. DSM44016, Rhodococcus erythropolis DSM44534, R. erythropolis PCM2150, and Rhodococcus ruber PCM2166. Application of scaled-up processes allowed to obtain hydroxy ketones 1-4c with the following yield range 36-62.5%. The propenylbenzene derivatives thus obtained and the starting compounds were tested for various biological activities, including antimicrobial, antioxidant, haemolytic, and anticancer activities, and their impact on membrane fluidity. Fungistatic activity assay against selected strains of Candida albicans results in MIC50 value varied from 37 to 124 µg/mL for compounds 1a, 3a-c, 4a,b, and 5a,b. The highest antiradical activity was shown by propenylbenzenes 1-5a with a double bond in their structure with EC50 value ranged from 19 to 31 µg/mL. Haemolytic activity assay showed no cytotoxicity of the tested compounds on human RBCs whereas, compounds 2b-4b and 2c-4c affected the fluidity of the RBCs membrane. The tested compounds depending on their concentration showed different antiproliferative activity against HepG2, Caco-2, and MG63. The results indicate the potential utility of these compounds as fungistatics, antioxidants, and proliferation inhibitors of selected cell lines.

2.
Pharmaceuticals (Basel) ; 16(4)2023 Apr 10.
Artigo em Inglês | MEDLINE | ID: mdl-37111327

RESUMO

Baicalin (7-D-glucuronic acid-5,6-dihydroxyflavone) belongs to natural flavonoids extracted from the roots of Scutellaria baicalensis, the plant used in traditional Chinese medicine. It has been proven that baicalin has various pharmacological activities, such as antioxidant, anti-inflammatory, anticancer, antibacterial, and anti-apoptotic ones. However, it is essential not only to determine the medical usefulness of baicalin, but also to find and develop the most effective methods for its extraction and detection. Therefore, the aim of this review was to summarize the current methods of detection and identification of baicalin and to present the medical applications of baicalin and the underlying mechanisms of its action. Based on the review of the latest literature, it can be concluded that liquid chromatography alone or together with mass spectrometry is the most commonly used method for the determination of baicalin. Recently, also new electrochemical methods have been established, e.g., biosensors with fluorescence, which have better detection limits, sensitivity, and selectivity.

3.
Chempluschem ; 88(5): e202300161, 2023 05.
Artigo em Inglês | MEDLINE | ID: mdl-36997498

RESUMO

The main aim of research was synthesis and spectroscopic characterization of new conjugates in which stigmasterol was linked via carbonate or succinyl linker with 1,3- and 1,2-acylglycerols of palmitic and oleic acid. Acylglycerols containing stigmasterol residue at internal position have been synthesized from 2-benzyloxypropane-1,3-diol or dihydroxyacetone. Their asymmetric counterparts containing stigmasterol residue attached to sn-3 position have been obtained from (S)-solketal. Eight synthesized conjugates were used to create the liposomes as nanocarriers of phytosterols to increase their stability and protect them from degradation during thermal-oxidative treatments. Fluorimetric and ATR-FTIR methods were used to determine the impact of synthesized conjugates on the physicochemical properties of the lipid bilayer. The results indicate that conjugates with palmitic acid are better candidates for use as the potential stigmasterol nanocarriers compared to those with oleic acid because they increase the stiffness of the lipid bilayer and temperature of the main phase transition. The obtained results are the first step in designing of stigmasterol-enriched liposomal carriers with higher thermo-oxidative stability for their potential use in the food industry.


Assuntos
Estigmasterol , Glicerídeos/química , Bicamadas Lipídicas , Estigmasterol/química , Estigmasterol/metabolismo , Ácido Oleico/química , Lipossomos/química
4.
Membranes (Basel) ; 12(11)2022 Oct 27.
Artigo em Inglês | MEDLINE | ID: mdl-36363609

RESUMO

Plant sterols are known for their health-promoting effects, lowering blood cholesterol levels and alleviating cardiovascular disease. In this work, we continue our research on the asymmetric acylglycerols in which fatty acid residues are replaced by two stigmasterol residues in sn-1 and sn-2 or sn-2 and sn-3 positions as new thermostable carriers of phytosterols for their potential application in foods or as components of new liposomes in the pharmaceutical industry. The aim of this manuscript was to compare and analyze the effects of four distigmasterol-modified acylglycerols (dStigMAs) on the fluidity and the main phase transition temperature of the model phospholipid membrane. Their properties were determined using differential scanning calorimetry (DSC), steady-state fluorimetry and attenuated total reflectance Fourier-transform infrared spectroscopy (ATR-FTIR). The determination of the effect of the tested compounds on the mentioned physicochemical parameters of the model membranes will allow for the determination of their properties and stability, which is essential for their practical application. The results indicated that all compounds effect on the physicochemical properties of the model membrane. The degree of these changes depends on the structure of the compound, especially the type of linker by which stigmasterol is attached to the glycerol backbone, as well as on the type of hydrocarbon chain.

5.
Molecules ; 27(11)2022 May 25.
Artigo em Inglês | MEDLINE | ID: mdl-35684341

RESUMO

New carriers of phytosterols; acylglycerols containing natural myristic acid at sn-1 and sn-3 positions and stigmasterol residue linked to sn-2 position by carbonate and succinate linker have been designed and synthesized in three-step synthesis from dihydroxyacetone (DHA). The synthetic pathway involved Steglich esterification of DHA with myristic acid; reduction of carbonyl group of 1,3-dimyristoylpropanone and esterification of 1,3-dimyristoylglicerol with stigmasterol chloroformate or stigmasterol hemisuccinate. The structure of the obtained hybrids was established by the spectroscopic methods (NMR; IR; HRMS). Obtained hybrid molecules were used to form new liposomes in the mixture with model phospholipid and their effect on their physicochemical properties was determined, including the polarity, fluidity, and main phase transition of liposomes using differential scanning calorimetry and fluorimetric methods. The results confirm the significant effect of both stigmasterol-containing acylglycerols on the hydrophilic and hydrophobic region of liposome membranes. They significantly increase the order in the polar heads of the lipid bilayer and increase the rigidity in the hydrophobic region. Moreover, the presence of both acylglycerols in the membranes shifts the temperature of the main phase transition towards higher temperatures. Our results indicate stabilization of the bilayer over a wide temperature range (above and below the phase transition temperature), which in addition to the beneficial effects of phytosterols on human health makes them more attractive components of novel lipid nanocarriers compared to cholesterol.


Assuntos
Lipossomos , Fitosteróis , Varredura Diferencial de Calorimetria , Glicerídeos , Humanos , Bicamadas Lipídicas/química , Lipossomos/química , Ácido Mirístico , Fitosteróis/química , Estigmasterol/química
6.
Int J Mol Sci ; 22(23)2021 Dec 05.
Artigo em Inglês | MEDLINE | ID: mdl-34884953

RESUMO

The aim of this work was the evaluation of the physico-chemical properties of a new type of liposomes that are composed of DPPC and bioconjugates of anisic acid with phosphatidylcholine. In particular, the impact of modified anisic acid phospholipids on the thermotropic parameters of liposomes was determined, which is crucial for using them as potential carriers of active substances in cancer therapies. Their properties were determined using three biophysical methods, namely differential scanning calorimetry (DSC), steady-state fluorimetry and attenuated total reflectance Fourier transform infrared spectroscopy (ATR-FTIR). Moreover, temperature studies of liposomes composed of DPPC and bioconjugates of anisic acid with phosphatidylcholine provided information about the phase transition, fluidity regarding chain order, hydration and dynamics. The DSC results show that the main phase transition peak for conjugates of anisic acid with phosphatidylcholine molecules was broadened and shifted to a lower temperature in a concentration- and structure-dependent manner. The ATR-FTIR results and the results of measurements conducted using fluorescent probes located at different regions in the lipid bilayer are in line with DSC. The results show that the new bioconjugates with phosphatidylcholine have a significant impact on the physico-chemical properties of a membrane and cause a decrease in the temperature of the main phase transition. The consequence of this is greater fluidity of the lipid bilayer.


Assuntos
Éteres de Hidroxibenzoatos/química , Fosfatidilcolinas/química , Varredura Diferencial de Calorimetria , Lipossomos/química , Transição de Fase , Espectroscopia de Infravermelho com Transformada de Fourier , Temperatura
7.
Sci Rep ; 11(1): 16003, 2021 08 06.
Artigo em Inglês | MEDLINE | ID: mdl-34362978

RESUMO

The aim of the study was to compare the impact of three synthesized chemical compounds from a group of methylated flavonoids, i.e. 2'-hydroxy-4-methylchalcone (3), 4'-methylflavanone (4), and 4'-methylflavone (5), on a red blood cell membranes (RBCMs), phosphatidylcholine model membranes (PC), and human serum albumin (HSA) in order to investigate their structure-activity relationships. In the first stage of the study, it was proved that all of the compounds tested do not cause hemolysis of red blood cells and, therefore, do not have a toxic effect. In biophysical studies, it was shown that flavonoids have an impact on the hydrophilic and hydrophobic regions of membranes (both RBCMs and PC) causing an increase in packing order of lipid heads and a decrease in fluidity, respectively. Whereas, on the one hand, the magnitude of these changes depends on the type of the compound tested, on the other hand, it also depends on the type of membrane. 4'-Methylflavanone and 4'-methylflavone are located mainly in the hydrophilic part of lipid membranes, while 2'-hydroxy-4-methylchalcone has a greater impact on the hydrophobic area. A fluorescence quenching study proved that compounds (3), (4) and (5) bind with HSA in a process of static quenching. The binding process is spontaneous whereas hydrogen bonding interactions and van der Waals forces play a major role in the interaction between the compounds and HSA.


Assuntos
Membrana Celular/metabolismo , Eritrócitos/metabolismo , Flavonoides/química , Flavonoides/metabolismo , Lipossomos/metabolismo , Albumina Sérica Humana/metabolismo , Animais , Flavonoides/classificação , Hemólise , Humanos , Suínos
8.
Food Funct ; 12(3): 1271-1290, 2021 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-33434253

RESUMO

The aim of the study was to broadly determine the biological activities of purple potato ethanolic extract of the Blue Congo variety (BCE). The antioxidant activity of BCE was determined in relation to liposome membranes, and peroxidation was induced by UVB and AAPH. To clarify the antioxidant activity of BCE, we investigated its interactions with hydrophilic and hydrophobic regions of a membrane using fluorimetric and FTIR methods. Next, we investigated the cytotoxicity and pro-apoptotic activities of BCE in two human colon cancer cell lines (HT-29 and Caco-2) and in normal cells (IPEC-J2). In addition, the ability to inhibit enzymes that are involved in pro-inflammatory reactions was examined. Furthermore, BCE interactions with serum albumin and plasmid DNA were investigated using steady state fluorescence spectroscopy and a single molecule fluorescence technique (TCSPC-FCS). We proved that BCE effectively protects lipid membranes against the process of peroxidation and successfully inhibits the cyclooxygenase and lipoxygenase enzymes. Furthermore, it interacts with the hydrophilic and hydrophobic parts of lipid membranes as well as with albumin and plasmid DNA. It was observed that BCE is more cytotoxic against colon cancer cell lines than normal IPEC-J2 cells; it also induces apoptosis in cancer cell lines, but does not induce cell death in normal cells.


Assuntos
Antineoplásicos Fitogênicos/farmacologia , Antioxidantes/farmacologia , Extratos Vegetais/farmacologia , Solanum tuberosum/química , Albuminas , Antineoplásicos Fitogênicos/química , Antioxidantes/química , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Inibidores de Ciclo-Oxigenase/química , Inibidores de Ciclo-Oxigenase/farmacologia , Humanos , Lipídeos/química , Lipossomos , Inibidores de Lipoxigenase/química , Inibidores de Lipoxigenase/farmacologia , Extratos Vegetais/química , Plasmídeos , Ligação Proteica , Espécies Reativas de Oxigênio , Albumina Sérica/química , Albumina Sérica/metabolismo
9.
Biomolecules ; 10(12)2020 11 24.
Artigo em Inglês | MEDLINE | ID: mdl-33255306

RESUMO

The aim of this work was the examination of biological activity of three selected racemic cis-ß-aryl-δ-iodo-γ-lactones. Tested iodolactones differed in the structure of the aromatic fragment of molecule, bearing isopropyl (1), methyl (2), or no substituent (3) on the para position of the benzene ring. A broad spectrum of biological activity as antimicrobial, antiviral, antitumor, cytotoxic, antioxidant, and hemolytic activity was examined. All iodolactones showed bactericidal activity against Proteus mirabilis, and lactones 1,2 were active against Bacillus cereus. The highest cytotoxic activity towards HeLa and MCF7 cancer cell lines and NHDF normal cell line was found for lactone 1. All assessed lactones significantly disrupted antioxidative/oxidative balance of the NHDF, and the most harmful effect was determined by lactone 1. Contrary to lactone 1, lactones 2 and 3 did not induce the hemolysis of erythrocytes after 48 h of incubation. The differences in activity of iodolactones 1-3 in biological tests may be explained by their different impact on physicochemical properties of membrane as the packing order in the hydrophilic area and fluidity of hydrocarbon chains. This was dependent on the presence and type of alkyl substituent. The highest effect on the membrane organization was observed for lactone 1 due to the presence of bulky isopropyl group on the benzene ring.


Assuntos
Antibacterianos/farmacologia , Antineoplásicos/farmacologia , Bacillus cereus/efeitos dos fármacos , Lactonas/farmacologia , Proteus mirabilis/efeitos dos fármacos , Antibacterianos/química , Antineoplásicos/química , Linhagem Celular , Proliferação de Células/efeitos dos fármacos , Ensaios de Seleção de Medicamentos Antitumorais , Humanos , Lactonas/química , Estrutura Molecular , Estresse Oxidativo/efeitos dos fármacos
10.
Biomolecules ; 10(1)2020 01 06.
Artigo em Inglês | MEDLINE | ID: mdl-31935977

RESUMO

Starting from 1-acetyl-1-cyclohexene, three enantiomeric pairs (ee ≥99%) of bicyclic δ-halo-γ-lactones with cyclohexane ring were obtained in five-step synthesis. The key stereochemical steps were lipase-catalyzed kinetic resolution of racemic 1-(cyclohex-1-en-1-yl) ethanol followed by transfer of chirality to ethyl 2-(2-ethylidenecyclohexyl) acetate in the Johnson-Claisen rearrangement. Synthesized halolactones exhibited antiproliferative activity towards canine B-cell leukemia cells (GL-1) and canine B-cell chronic leukemia cells (CLB70) and the most potent (IC50 18.43 ± 1.46 µg/mL against GL-1, IC50 11.40 ± 0.40 µg/mL against CLB70) comparable with the control etoposide, was (1R,6R,1'S)-1-(1'-chloroethyl)-9- oxabicyclo[4.3.0]nonan-8-one (8b). All halolactones did not have a toxic effect on erythrocytes and did not change the fluidity of membranes in the hydrophobic region of the lipid bilayer. Only weak changes in the hydrophilic area were observed, like the degree of lipid packing and associated hydration. The racemic halolactones were also tested for their antimicrobial properties and found to exhibit selectivity towards bacteria, in particular, towards Proteus mirabilis ATCC 35659.


Assuntos
Cicloexanos/síntese química , Lactonas/síntese química , Antibacterianos/química , Anti-Infecciosos/química , Bactérias , Membrana Celular , Cicloexanos/química , Cinética , Lactonas/química , Estrutura Molecular , Estereoisomerismo
11.
Molecules ; 23(11)2018 Nov 20.
Artigo em Inglês | MEDLINE | ID: mdl-30463384

RESUMO

Three novel enantiomeric pairs of bromolactones possesing a 2,5-dimethylphenyl substituent at the ß-position of the lactone ring have been synthesized from corresponding enantiomeric (E)-3-(2',5'-dimethylphenyl)hex-4-enoic acids (4) by kinetically controlled bromolactonization with N-bromosuccinimide (NBS). γ-Bromo-δ-lactones (5) were isolated as the major products. Absolute configurations of stereogenic centers of γ-bromo-δ-lactones (5) were assigned based on X-ray analysis; configurations of cis δ-bromo-γ-lactones (6) and trans δ-bromo-γ-lactones (7) were determined based on mechanism of bromolactonization. Synthesized compounds exhibited significant antiproliferative activity towards the four canine cancer cell lines (D17, CLBL-1, CLB70, and GL-1) and one human cancer line (Jurkat). Classifying the compounds in terms of activity, the most active were enantiomers of trans δ-bromo-γ-lactones (7) followed by enantiomers of cis isomer (6) and enantiomeric γ-bromo-δ-lactones (5). Higher activity was observed for all stereoisomers with S configuration at C-4 in comparison with their enantiomers with 4R configuration. Synthesized compounds did not induce hemolysis of erythrocytes. The results of the interaction of bromolactones with red blood cell membranes suggest that these compounds incorporate into biological membranes, concentrating mainly in the hydrophilic part of the bilayer but have practically no influence on fluidity in the hydrophobic region. The differences in interactions with the membrane between particular enantiomers were observed only for γ-lactones: stronger interactions were found for enantiomer 4R,5R,6S of cis γ-lactone (6) and for enantiomer 4S,5R,6S of trans γ-lactone (7).


Assuntos
Antineoplásicos/síntese química , Antineoplásicos/farmacologia , Lactonas/síntese química , Lactonas/farmacologia , Animais , Antineoplásicos/química , Linhagem Celular Tumoral , Membrana Celular/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Cães , Humanos , Células Jurkat , Cinética , Lactonas/química , Estrutura Molecular , Estereoisomerismo
12.
Molecules ; 23(10)2018 Oct 08.
Artigo em Inglês | MEDLINE | ID: mdl-30297646

RESUMO

In our research we used the extract from dietary supplement of elderberry (EE) and its dominant anthocyanin-cyanidin 3-O-glucoside (Cy 3-gluc). By interacting with a model membrane that reflects the main lipid composition of tumor membranes, the extract components, including Cy 3-gluc, caused an increase in packing order, mainly in the hydrophilic region of the membrane. It can thus be stated that EE caused a rigidifying effect, which is fundamental for understanding its anticancer and antioxidant activity. This study represents the first attempt to unravel the mechanism of interaction of elderberry extract with membranes. The results of the interaction with human serum albumin (HSA) proved that the studied substance quenches the fluorescence of HSA through a static mechanism in which the main interaction forces are Van der Waals and hydrogen bonding. The antioxidant activity of EE and Cy 3-gluc on liposomal membranes, antiradical properties and ability to inhibited the activity of the enzymes cyclooxygenase-1 and cyclooxygenase-2 were also demonstrated. Moreover, the anticancer activity of EE and Cy 3-gluc on human breast adenocarcinoma cell line were investigated. In addition, EE also exhibited the ability to form lipid aggregates in the form of liposomal capsules that can be applied as carriers of active biological substances, and the highest efficacy of EE encapsulation was obtained for multilayered liposome formulations.


Assuntos
Antocianinas/farmacologia , Neoplasias da Mama/tratamento farmacológico , Membrana Celular/efeitos dos fármacos , Glucosídeos/farmacologia , Sambucus/química , Antocianinas/química , Antioxidantes/química , Antioxidantes/farmacologia , Neoplasias da Mama/genética , Neoplasias da Mama/patologia , Linhagem Celular Tumoral , Ciclo-Oxigenase 1/genética , Ciclo-Oxigenase 2/genética , Feminino , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Glucosídeos/química , Humanos , Ligação de Hidrogênio/efeitos dos fármacos , Metabolismo dos Lipídeos/efeitos dos fármacos , Extratos Vegetais/química , Extratos Vegetais/farmacologia , Albumina Sérica Humana/antagonistas & inibidores , Albumina Sérica Humana/química
13.
J Membr Biol ; 251(5-6): 735-745, 2018 12.
Artigo em Inglês | MEDLINE | ID: mdl-30350012

RESUMO

Interactions of tributyltin (TBTA) and triphenyltin (TPhTA) 2-[4 (dimethylamino)phenylazo]benzoates, showing promising cytostatic activity against tumor cells, with erythrocytes and with erythrocyte membranes and model lipid membranes have been investigated. The effect of TBTA and TPhTA on the erythrocyte and its model membrane was investigated by the microscopic and spectroscopic methods. Interaction of tin complexes with the membrane was determined on the basis of hemolytic activity, changes induced in the shape of erythrocytes, as well as physicochemical parameters of the membrane, such as fluidity. The studies showed that the compounds in higher concentration induce hemolysis; however, TBTA is more toxic than TPhTA. Both TBTA and TPhTA induce morphological alterations in red blood cells-from discocytes to spherocytes and from discocytes to echinocytes. The results suggest that investigated complexes interact with the erythrocyte membrane, change its properties, and probably locate themselves in the hydrophilic part of the membrane, which agrees with conclusions drawn from investigation of erythrocyte membranes and model lipid membranes with the help of fluorescence and infrared spectroscopy.


Assuntos
Membrana Celular/química , Eritrócitos/química , Animais , Hemólise , Humanos , Compostos Orgânicos de Estanho/química , Compostos de Trialquitina/química
14.
Molecules ; 22(7)2017 Jul 21.
Artigo em Inglês | MEDLINE | ID: mdl-28754033

RESUMO

The synthesis of different classes of prenylated aglycones (α,ß-dihydroxanthohumol (2) and (Z)-6,4'-dihydroxy-4-methoxy-7-prenylaurone (3)) was performed in one step reactions from xanthohumol (1)-major prenylated chalcone naturally occurring in hops. Obtained flavonoids (2-3) and xanthohumol (1) were used as substrates for regioselective fungal glycosylation catalyzed by two Absidia species and Beauveria bassiana. As a result six glycosides (4-9) were formed, of which four glycosides (6-9) have not been published so far. The influence of flavonoid skeleton and the presence of glucopyranose and 4-O-methylglucopyranose moiety in flavonoid molecule on binding to main protein in plasma, human serum albumin (HSA), and inhibition of cyclooxygenases COX-1 and COX-2 were investigated. Results showed that chalcone (1) had the highest binding affinity to HSA (8.624 × 104 M-1) of all tested compounds. It has also exhibited the highest inhibition of cyclooxygenases activity, and it was a two-fold stronger inhibitor than α,ß-dihydrochalcone (2) and aurone (3). The presence of sugar moiety in flavonoid molecule caused the loss of HSA binding activity as well as the decrease in inhibition of cyclooxygenases activity.


Assuntos
Ciclo-Oxigenase 1/metabolismo , Ciclo-Oxigenase 2/metabolismo , Flavonoides/farmacologia , Glicosilação/efeitos dos fármacos , Prenilação/efeitos dos fármacos , Albumina Sérica Humana/metabolismo , Benzofuranos/química , Benzofuranos/farmacologia , Flavonoides/química , Fungos/metabolismo , Glicosídeos/química , Glicosídeos/metabolismo , Humanos , Humulus/química , Propiofenonas/química , Propiofenonas/farmacologia
15.
Acta Pol Pharm ; 74(2): 660-669, 2017 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-29624272

RESUMO

The studies were designed to determine the polyphenolic composition and biological activity of extracts from fruits (SFE) and leaves (SLE) of Saskatoon (Amelanchier alnifolia Nutt.) in relation to erythrocyte membranes. A detailed quantitative and qualitative analysis of extracts was conducted, using the chro- matographic (UPLC-DAD, UPLC-ESI-MS) and spectrophotometric (Folin-Ciocalteu) methods. The biological activity of the extracts was investigated in relation to erythrocytes and isolated membranes of erythrocytes by using spectrophotometric, fluorimetric and microscopic methods and determined on the basis of hemolytic and antioxidant activity of the extracts and their impact on physical properties of the membrane such as: osmotic resistance, shape of erythrocytes, packing order of the polar head of lipids and fluidity of the membrane. The results showed that the tested extracts are rich sources of polyphenols, primarily from the group of flavonoids; in leaves dominating flavonols and anthocyanins in fruits. The SFE and SLE extracts to varying degree modify the physical properties of the erythrocyte membrane, causing formation of echinocytes, an increase in osmotic resistance and changes in the polar part of the membrane. Furthermore, the substances markedly protect erythrocytes and their membranes against oxidation induced by different physico-chemical factors. The findings indicate that the polyphenolic compounds contained in extracts of Saskatoon do not destroy biological membranes but effectively protect them against oxidation by way of interacting with the membrane surface. The extracts could effectively protect the organism and food products from the harmful effects of free radicals.


Assuntos
Antioxidantes/farmacologia , Membrana Eritrocítica/efeitos dos fármacos , Frutas/química , Extratos Vegetais/farmacologia , Folhas de Planta/química , Polifenóis/farmacologia , Rosaceae/química , Animais , Antioxidantes/isolamento & purificação , Cromatografia Líquida de Alta Pressão , Citoproteção , Relação Dose-Resposta a Droga , Membrana Eritrocítica/metabolismo , Membrana Eritrocítica/patologia , Hemólise/efeitos dos fármacos , Fluidez de Membrana/efeitos dos fármacos , Pressão Osmótica/efeitos dos fármacos , Estresse Oxidativo/efeitos dos fármacos , Fitoterapia , Extratos Vegetais/isolamento & purificação , Plantas Medicinais , Polifenóis/isolamento & purificação , Espectrofotometria , Sus scrofa , Espectrometria de Massas em Tandem
16.
J Membr Biol ; 249(1-2): 155-70, 2016 04.
Artigo em Inglês | MEDLINE | ID: mdl-26581904

RESUMO

Buckwheat is a valuable source of many biologically active compounds and nutrients. It has properties that reduce blood cholesterol levels, and so reduces the risk of atherosclerosis, seals the capillaries, and lowers blood pressure. The aim of the study was to determine quantitative and qualitative characteristics of polyphenols contained in extracts from buckwheat husks and stalks, the biological activity of the extracts, and biophysical effects of their interaction with the erythrocyte membrane, treated as a model of the cell. An analysis of the extract's composition has shown that buckwheat husk and stalk extracts are a rich source of polyphenolic compounds, the stalk extracts showing more compounds than the husk extract. The study allowed to determine the location which incorporated polyphenols occupy in the erythrocyte membrane and changes in the membrane properties caused by them. It was found that the extracts do not induce hemolysis of red blood cells, causing an increase in osmotic resistance of erythrocytes. They affect mainly the hydrophilic region by changing the degree of order of the polar heads of lipids, but do little to change the fluidity of the membrane and its hydration. The results showed also that polyphenolic substances included in the extracts well protect the membranes of red blood cells against oxidation and exhibit anti-inflammatory effect.


Assuntos
Membrana Celular/efeitos dos fármacos , Fagopyrum/química , Extratos Vegetais/química , Extratos Vegetais/farmacologia , Substâncias Protetoras/química , Substâncias Protetoras/farmacologia , Animais , Anti-Inflamatórios não Esteroides/química , Anti-Inflamatórios não Esteroides/farmacologia , Antioxidantes/química , Antioxidantes/farmacologia , Cromatografia Líquida de Alta Pressão , Membrana Eritrocítica/efeitos dos fármacos , Eritrócitos/citologia , Eritrócitos/efeitos dos fármacos , Eritrócitos/ultraestrutura , Hemólise/efeitos dos fármacos , Concentração Inibidora 50 , Fluidez de Membrana/efeitos dos fármacos , Compostos Fitoquímicos/química , Compostos Fitoquímicos/farmacologia , Espectroscopia de Infravermelho com Transformada de Fourier , Suínos
17.
J Membr Biol ; 246(7): 545-56, 2013 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-23774969

RESUMO

The aim of the study was to identify and determine the percent content of polyphenols in extracts from leaves and hawthorn bark, to examine the effect of the extracts on the properties of the biological membrane as well as to determine their antioxidant activity toward membrane lipids. In particular, a biophysical investigation was conducted on the effect of hawthorn extracts on the osmotic resistance and morphology of erythrocyte cells and on the packing of the heads of membrane lipids. Analysis of the polyphenol content of extracts used the HPLC method. Analysis of the polyphenol composition has shown a dominant share of procyanidins and epicatechin in both extracts. The research showed that the polyphenolic compounds contained in hawthorn extracts are incorporated mainly into the hydrophilic part of the erythrocyte membrane, inducing echinocyte shapes. They also diminish the packing order of the lipid polar heads of the membrane, as evidenced by the lowered generalized polarization values of Laurdan. The substances used induced increased osmotic pressure of erythrocytes, making them less sensitive to changes in osmotic pressure. The presence of the extract compounds in the outer hydrophilic part of the erythrocyte membrane, evidenced by examination of the shapes and packing in the hydrophilic part of membrane, indicates that the substances constitute a kind of barrier that protects the erythrocyte membrane against free radicals, while the membrane-bound extracts do not disturb the membrane structure and, thus, do not cause any side effects.


Assuntos
Crataegus/química , Membrana Eritrocítica/efeitos dos fármacos , Extratos Vegetais/farmacologia , Antioxidantes/química , Antioxidantes/farmacologia , Eritrócitos/citologia , Eritrócitos/efeitos dos fármacos , Hemólise/efeitos dos fármacos , Concentração Inibidora 50 , Pressão Osmótica , Oxirredução/efeitos dos fármacos , Casca de Planta/química , Extratos Vegetais/química , Folhas de Planta/química , Polifenóis/química
18.
Cell Mol Biol Lett ; 18(1): 89-101, 2013 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-23271433

RESUMO

Cationic gemini surfactants are an important class of surface-active compounds that exhibit much higher surface activity than their monomeric counterparts. This type of compound architecture lends itself to the compound being easily adsorbed at interfaces and interacting with the cellular membranes of microorganisms. Conventional cationic surfactants have high chemical stability but poor chemical and biological degradability. One of the main approaches to the design of readily biodegradable and environmentally friendly surfactants involves inserting a bond with limited stability into the surfactant molecule to give a cleavable surfactant. The best-known example of such a compound is the family of ester quats, which are cationic surfactants with a labile ester bond inserted into the molecule. As part of this study, a series of gemini ester quat surfactants were synthesized and assayed for their biological activity. Their hemolytic activity and changes in the fluidity and packing order of the lipid polar heads were used as the measures of their biological activity. A clear correlation between the hemolytic activity of the tested compounds and their alkyl chain length was established. It was found that the compounds with a long hydrocarbon chain showed higher activity. Moreover, the compounds with greater spacing between their alkyl chains were more active. This proves that they incorporate more easily into the lipid bilayer of the erythrocyte membrane and affect its properties to a greater extent. A better understanding of the process of cell lysis by surfactants and of their biological activity may assist in developing surfactants with enhanced selectivity and in widening their range of application.


Assuntos
Materiais Biocompatíveis/síntese química , Membrana Eritrocítica/efeitos dos fármacos , Compostos de Amônio Quaternário/síntese química , Tensoativos/síntese química , Adsorção , Materiais Biocompatíveis/farmacologia , Biodegradação Ambiental , Cátions , Células Cultivadas , Ésteres , Fluorometria , Hemólise/efeitos dos fármacos , Humanos , Hidrólise , Micelas , Compostos de Amônio Quaternário/farmacologia , Relação Estrutura-Atividade , Propriedades de Superfície , Tensoativos/farmacologia
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