BMC Complementary and Alternative Medicine, Dec 1, 2014
Background: The young shoots of Rubus idaeus are traditionally used as a herbal remedy in common ... more Background: The young shoots of Rubus idaeus are traditionally used as a herbal remedy in common cold, fever and flu-like infections yet there is no research concerning this plant material. The aim of the study was to evaluate the chemical composition and biological properties of raspberry shoots from 11 cultivar varieties. Methods: The methanol extracts were subjected to chromatographic analysis using HPLC-DAD-ESI-MS, and two-dimensional 'comprehensive' LCxLC techniques. The biological activity of the shoot extract from the 'Willamette' cultivar variety was evaluated. Antioxidant activity was tested using DPPH and phosphomolybdenum assay. Antimicrobial activity was estimated towards 15 strains of human pathogenic bacteria using broth microdilution method. Cytotoxic activity was tested using MTT cell viability assay. Results: The dominating compounds identified in the shoots of R. idaeus were ellagic acid (26.1-106.8 mg/100 g) and sanguiin H-6 (139.2-633.1 mg/100 g). The best separation of compounds present in the analysed polyphenol complex, was achieved by 'comprehensive' LCxLC method using Nucleodur Sphinx RP column in the first dimension and Chromolith Performance column in the second dimension. The shoot extract was found to be a strong antioxidant (EC 50 19.4 μg/ml, AAE 427.94 mg/g) and displayed the strongest bactericidal properties towards Corynebacterium diphtheriae. The extract revealed higher cytotoxic activity towards the HL-60 cells (IC 50 110 μg/ml) than HeLa (IC 50 300 μg/ml). Conclusions: The shoots of R. idaeus stand out as a valuable source of sanguiin H-6 and ellagic acid and possess a number of biological properties including antioxidative, antimicrobial and cytotoxic.
European journal of medicinal chemistry, May 1, 2006
Two series of 1-(6-chloro-1,1-dioxo-1,4,2-benzodithiazin-3-yl)-4-arylsemicarbazides 6-17 and 2-ar... more Two series of 1-(6-chloro-1,1-dioxo-1,4,2-benzodithiazin-3-yl)-4-arylsemicarbazides 6-17 and 2-arylamino-8-chloro-5,5-dioxo[1,2,4]triazolo [2,3-b][1,4,2]benzodithiazines 18-26 were prepared in order to evaluate their biological activity. Compounds 6 and 18-26 were tested for their in vitro cytotoxic potency against 12 human cancer cell lines. The compounds 6 and 19 were inactive, whereas triazolobenzodithiazines 18, 20-26 possess tumor growth inhibitory properties. The prominent methyl 8-chloro-2-(4-chlorophenylamino)-5,5-dioxo[1,2,4]triazolo[2,3-b][1,4,2]benzodithiazine-7-carboxylate (21) exhibited potency higher or comparable to cisplatin. Moreover, compounds 6, 9, 19 and 23-25 with structure similar to other chemotherapeutic agents were tested for their antibacterial activity and exhibited MIC and MBC against Staphylococcus aureus (3.9-31.5 μg ml).
tris-[(4,7-diphenyl-1,10-phenanthroline)ruthenium(II)] dichloride (Ru(DPP)3Cl2), a fluorescent se... more tris-[(4,7-diphenyl-1,10-phenanthroline)ruthenium(II)] dichloride (Ru(DPP)3Cl2), a fluorescent sensor which is sensitive to the amount of oxygen in the sample, was applied using the fluorescent optical respirometry (FOR) technique. The oxygen in the samples quenches the fluorescence. The fluorescence intensity depends on the metabolic rate of the viable microorganisms. The effect of DMSO and plant extracts on bacteria was determined by FOR. It was shown that the MIC values obtained by FOR were consistent with the results of the MIC determinations using the method of serial dilutions; at the same time, the effects of concentrations lower than the growth-inhibitory concentrations on microbial cells were demonstrated. The FOR method enables the detection of multiplying bacteria in sterile and non-sterile pharmaceutical preparations in real time, which significantly shortens the time required to obtain results and allows the introduction of repair processes in the production. This metho...
Kalanchoe species are succulents occurring in tropical regions. They have many biological and pha... more Kalanchoe species are succulents occurring in tropical regions. They have many biological and pharmacological properties. In this study, the cytotoxic and antimicrobial activities of water and dichloromethane Kalanchoe fractions obtained from ethanol extracts of three Kalanchoe species—K. daigremontiana, K. pinnata, and K. blossfeldiana were estimated. The cytotoxic effect was assessed on human cancer cell lines—ovarian SKOV-3, cervical HeLa, breast MCF-7, and melanoma A375—by MTT (3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide) assay. The antimicrobial activity was estimated on selected Gram-positive and Gram-negative bacteria strains and on Candida albicans. The phytochemical analysis of selected Kalanchoe extracts was conducted by LC-QTOF-MS. The obtained results showed that the water fraction of K. blossfeldiana was active both on the tested cancer cells (IC50 values were 28.28 ± 2.76 and 32.51 ± 0.69 µg/mL on HeLa and SKOV-3, respectively) and bacteria strains (MI...
The measurement of oxygen consumption is an important element in the understanding of an organism... more The measurement of oxygen consumption is an important element in the understanding of an organism’s metabolic state. Oxygen is also a phosphorescence quencher, which allows the evaluation of phosphorescence emitted by oxygen sensors. Two Ru(II)-based oxygen-sensitive sensors were used to study the effect of chemical compounds [(1) = [CoCl2(dap)2]Cl, and (2) = [CoCl2(en)2]Cl (AmB = amphotericin B) against reference and clinical strains of Candida albicans. The tris-[(4,7-diphenyl-1,10-phenanthroline)ruthenium(II)] chloride ([Ru(DPP)3]Cl2) (Box) adsorbed onto the DavisilTM silica gel was embedded in the silicone rubber Lactite NuvaSil® 5091 and the coating on the bottom of 96-well plates. The water-soluble oxygen sensor (BsOx = tris-[(4,7-diphenyl-1,10-phenanthrolinedisulphonic acid disodium)ruthenium(II)] chloride ‘x’ hydrate = {Ru[DPP(SO3Na)2]3}Cl2 = water molecules were omitted in the BsOx formula) was synthesized and characterized by RP-UHPLC, LCMS, MALDI, elemental analysis, ATR,...
Mangiferin is a strong antioxidant that presents a wide range of biological activities. The aim o... more Mangiferin is a strong antioxidant that presents a wide range of biological activities. The aim of this study was to evaluate, for the first time, the influence of mangiferin on tyrosinase, an enzyme responsible for melanin synthesis and the unwanted browning process of food. The research included both the kinetics and molecular interactions between tyrosinase and mangiferin. The research proved that mangiferin inhibits tyrosinase activity in a dose-dependent manner with IC50 290 +/− 6.04 µM, which was found comparable with the standard kojic acid (IC50 217.45 +/− 2.54 µM). The mechanism of inhibition was described as mixed inhibition. The interaction between tyrosinase enzyme and mangiferin was confirmed with capillary electrophoresis (CE). The analysis indicated the formation of two main, and four less significant complexes. These results have also been supported by the molecular docking studies. It was indicated that mangiferin binds to tyrosinase, similarly to L-DOPA molecule, b...
This article is an open access article distributed under the terms and conditions of the Creative... more This article is an open access article distributed under the terms and conditions of the Creative Commons Attribution (CC BY
This article is an open access article distributed under the terms and conditions of the Creative... more This article is an open access article distributed under the terms and conditions of the Creative Commons Attribution (CC BY
In subtropical regions the extracts from Phyllanthus species are used in the treatment of bacteri... more In subtropical regions the extracts from Phyllanthus species are used in the treatment of bacterial, fungal and parasitic diseases (e.g. P. niruri, P. amarus). Literature data showed that antimicrobial activity of Phyllanthus species results from synergistic effects of occurring secondary metabolites. The MIC and MBC values were determined to show antibacterial activity of extracts from shoot cultures of P. glaucus, P. multiflorus and P. juglandifolius and shoot culture and non-transformed root culture of P. amarus. The dry extracts dissolved in either DMSO or methanol were examined against strains of Gram (+) bacteria – Streptococcus G, S. aureus, S. epidermidis, B. subtilis, C. sporogenes, E. hirae, strains of Gram (-) bacteria – M. catarrhalis, K. pneumoniae, E. coli, P. vulgaris, P. aeruginosa, H. pylori as well as a yeast C. albicans. As controls, the alkaloid securinine, present as a dominant compound of the alkaloid fraction in the shoot culture of P. glaucus, and flavan-3-ol – catechin present in all tested species, were used. Using DMSO to dissolve dry extracts higher MIC values were observed than when dissolved in methanol. The obtained results showed the differences in bacterial susceptibility depending on the Phyllanthus species. For the methanol extracts antimicrobial activity expressed as MIC was in a range from 0.01 mg/mL to 5.0 mg/mL, while the MBC value was determined from 0.01 mg/mL to 10.0 mg/mL. Securinine and catechin were active in a range from 0.03 to 0.25 mg/mL showing the highest activity against Streptococcus G and P. aeruginosa (securinine) and H. pylori (catechin). All extracts and standards were inactive against E. hirae while the most susceptible strain was M. catarrhalis (MBC 0.01 mg/l). Acknowledgement: This Project was supported by the Ministry of Science and Higher Education of the Republic of Poland, from the quality-promoting subsidy, under the Leading National Research Centre (KNOW) programme for the years 2012 – 2017".
Cinnamic acid is a plant metabolite with antimicrobial, anticancer, and antioxidant properties. I... more Cinnamic acid is a plant metabolite with antimicrobial, anticancer, and antioxidant properties. Its synthetic derivatives are often more effective in vitro than parent compounds due to stronger biological activities. In our study, we synthesized ten new N–(4–chloro–2–mercapto–5–methylphenylsulfonyl)cinnamamide derivatives, containing two pharmacophore groups: cinnamic acid moiety and benzenesulfonamide. The antimicrobial activity of the obtained compounds was estimated using different types of Gram-positive and Gram-negative bacteria, fungus species of Candida albicans, as well as clinical strains. The compounds were evaluated on biofilm formation and biofilm formed by Staphylococcus clinical strains (methicillin–resistance S. aureus MRSA and methicillin–resistance coagulase–negative Staphylococcus MRCNS). Furthermore, blood bacteriostatic activity test was performed using S. aureus and S. epidermidis. In cytotoxic study, we performed in vitro hemolysis assay on domestic sheep perip...
Context: Kalanchoe species (Crassulaceae) are widely used in traditional medicine as remedies in ... more Context: Kalanchoe species (Crassulaceae) are widely used in traditional medicine as remedies in infectious diseases and cancer treatment. Objective: Cytotoxic and antimicrobial activities of Kalanchoe daigremontiana Raym.-Hamet & H. Perrier, K. pinnata (Lam.) Pers., and K. blossfeldiana Poelln. extracts were determined. The relationship between biological activities and the extracts bufadienolides content was also investigated. Materials and methods: Fresh leaves of Kalanchoe species were macerated with 95% ethanol or water. The quantitative analysis of bufadienolides in the extracts was carried out with mass spectrometry. Cytotoxicity tests were performed on human cancer cell lines-HeLa, SKOV-3, MCF-7, and A375 by MTT (3-[4,5-dimethylthiazol-2-yl]-2,5-diphenyltetrazolium bromide) assay and Real-Time Cell Analysis system. The microbiological study was done using a few bacteria strains (b-hemolytic Streptococcus, Corynebacterium diphtheriae, Staphylococcus aureus, Staphylococcus epidermidis, Enterococcus hirae, Escherichia coli) and Candida albicans. Results: The K. blossfeldiana ethanol extract and K. daigremontiana water extract exhibited the most potent cytotoxic activity (IC 50 < 19 mg/mL for HeLa and SKOV-3 cells). The strongest antibacterial effects showed ethanol extract of K. blossfeldiana and K. pinnata (MIC values were 8.45, 8.45, 0.25 and <33.75 mg/mL for S. aureus, S. epidermidis, and E. hirae, respectively). The highest total amount of bufadienolides was in K. daigremontiana ethanol extract. In contrast, K. blossfeldiana ethanol extract did not show the presence of these compounds. Conclusions: Kalanchoe blossfeldiana ethanol extract is a potential candidate for cancer and bacterial infection treatment. Additionally, the biological effects of Kalanchoe extracts are not dependent on the presence and amount of bufadienolides in the plant extracts.
Cross-linked polysiloxane microspheres containing a large number of SiOH groups were modified by ... more Cross-linked polysiloxane microspheres containing a large number of SiOH groups were modified by introduction of organic thiol groups, which were further used for the functionalization of the microspheres with silver thiolate groups. The microspheres were characterized by 29 Si MAS NMR, 13 C MAS NMR, SEM, XPS and elemental analysis. They were tested as biocides against selected Gram-positive and Gram-negative bacteria strains and exhibited high bactericidal activity. Separately, linear polysiloxane polymers equipped with organothiol groups and loaded with silver were synthesized. Their antibacterial activity was compared with that of silver thiolate-functionalized microspheres. Different shape of particles and a different form of silver explained somewhat lower activity of polymers.
Journal of Inorganic and Organometallic Polymers and Materials, 2006
Octa(3-chloropropylsilsesquioxane), (T-ClPr) 8 , and a soluble, low molecular weight, poly(3chlor... more Octa(3-chloropropylsilsesquioxane), (T-ClPr) 8 , and a soluble, low molecular weight, poly(3chloropropylsilsesquioxane) were subjected to a reaction with dimethyl-n-octylamine to convert part or almost all the chloropropyl groups to corresponding quaternary ammonium salt (QAS) groups. Polysilsesquioxanes containing secondary n-amylammonium salt (SAS) groups were synthesized by reaction of n-alkyl bromides with poly(3-aminopropylsilsesquioxane) of limited molecular weight or by amination of n-amyl bromide with 3-aminopropyltriethoxysilane followed by hydrolysis and polycondensation. The antibacterial activity of these QASand SAS-containing silsesquioxane materials against two representative Gram-positive and three representative Gram-negative bacterium strains were tested. Most of these materials showed high or moderate activity against Gram-positive bacteria and moderate or weak activity against Gram-negative bacteria.
An analysis of the usefulness of the fluorescence optical respirometry test method to study sever... more An analysis of the usefulness of the fluorescence optical respirometry test method to study several antimicrobials was performed. An oxygen-sensitive sensor: ruthenium-tris(4,7-diphenyl-1,10-phenanthroline) dichloride (Ru(DPP)3Cl2), the phosphorescence of which is quenched by molecular oxygen, was synthesised according to a method modified by us and then applied. A prototype sensitive measurement system was designed and constructed. Analyses of the impact of various antimicrobial chemical factors were performed: ampicillin, co-trimoxazole, nystatin, and newly synthesised compounds. It was shown that optical respirometry allows for analysis of the culture growth kinetics of bacteria and fungi and determination of cell growth parameters. It was shown also that MIC values obtained by fluorescence optical respirometry are consistent with the results of the MIC determinations made by serial dilution method (traditional MIC testing using CLSI). The method allows the time to obtain results...
Journal of Inorganic and Organometallic Polymers and Materials, 2007
Three types of silica particles modified with vinyl groups were obtained: (i) xerogel formed by h... more Three types of silica particles modified with vinyl groups were obtained: (i) xerogel formed by hydrolytic polycondensation of the mixture of tetramethoxysilane (TMOS) and 1,1,1,7-tetramethoxy-3,5,7-trimethyl-3,5,7trivinyltetrasiloxane, (ii) mesoporous silica obtained from the same precursors in the presence of the cetyltrimethylammonium bromide (CTAB), and (iii) commercial Fluka silica gel 60A with a vinyltriethoxysilane-treated surface. Vinyl groups on these silica materials were transformed into silyl chloride by hydrosilylation with HMe 2 SiCl. These groups were used to graft living polysiloxane that was synthesized by anionic ring-opening polymerization of 2,4,6tri(3-chloropropyl)-2,4,6-trimethylcyclotrisiloxane and initiated by BuLi. Chloropropyl groups on the grafted polymer were used to quaternize N,N-dimethyl-n-octylamine. Silica particles with grafted polysiloxane having quaternary ammonium salt (QAS) groups pendant to polymer chains were obtained. Silica material with QAS groups directly attached to the surface were generated by the action of N,Ndimethyl-n-octylamine on particles obtained by the sol-gel process involving tetraethoxysilane (TEOS) with 3-chloropropyltriethoxysilane. The bacteriocidal properties of all these materials were tested in water suspension against five representative strains for Gram-positive and Gram-negative bacteria. Some of the silica-polysiloxane hybrid materials have good antibacterial properties against Gram-positive strains, but not as good as the non-tethered QAS-substituted polysiloxane in water solution. The QAS groups that are directly bonded to the silica material surface are inactive. Keywords Silica hybrids Á Sol-gel silica Á Silica materials Á Functionalized polysiloxanes Á Biocidal polymers Á QAS Á Biocides Á Functionalized silica
Eighteen new 2,6-disubstituted acrylonitriles and two new (benzimidazol-1-yl)-acetamide derivativ... more Eighteen new 2,6-disubstituted acrylonitriles and two new (benzimidazol-1-yl)-acetamide derivatives were prepared and screened for antibacterial and cytotoxic activities on 12 human cancer cell lines. Based on the lead structure 2-(benzimidazol-2-yl)-3-(5-nitrothiophen-2-yl) acrylonitrile it was found that placement of methyl groups at the 5,6 positions of the benzimidazole ring lead to a 3-fold increase in overall cytotoxic activity. Replacing the nitrothiophene for pyridine reduced cytotoxic activity as did replacing the nitro group for a methoxy group. Cytotoxic activity was only slightly reduced when the benzimidazole ring was replaced by a imidazo[4,5-b]pyridine or a benzthiazole ring but replacement by benzoxazole led to a substantial decrease in activity. Moving the acrylonitrile group from position 2 to position 1 of the benzimidazole ring also resulted in moderately active compounds. (Benzimidazol-1-yl)acetamides showed only modest activity. The structure-activity relationships found in the cytotoxicity studies are mirrored in the results of the antibacterial experiments.
An on-line LC-LC-DAD-ESI-MS method was established for quantitation of C-glycosylflavones in fenu... more An on-line LC-LC-DAD-ESI-MS method was established for quantitation of C-glycosylflavones in fenugreek seeds. Anti-Helicobacter pylori activity of standardized 70% methanol extract from fenugreek seeds and vitexin has been demonstrated.
ETHNOPHARMACOLOGICAL RELEVANCE Bistort rhizome (Bistorta officinalis) is a traditionally used pla... more ETHNOPHARMACOLOGICAL RELEVANCE Bistort rhizome (Bistorta officinalis) is a traditionally used plant material popular in Europe and Asia in the treatment of diarrhea and as a topical agent for skin conditions. It contains tannins mostly condensed flavan-3-ol derivatives. However, the in-depth phytochemical investigation of infusions from this plant materials is still lacking. Additionally, the scientific reports supporting the traditional topical application of bistort rhizome are scarce. AIM OF THE STUDY The major objective of the present study was to comprehensively investigate the chemical composition of infusion from subterranean parts of common bistort both using hyphenated chromatographic technique and isolation approach. Additionally, the influence of water extract on pro-inflammatory functions of human neutrophils was performed. As bacterial infections play a crucial role in the generation of skin inflammations the antimicrobial activity of the infusion and its major components was established. MATERIAL AND METHODS The chemical composition of the infusion was established using UHPLC-DAD-MS3 method. Major compounds which could not be identified using chromatographic analysis were isolated by column chromatography and preparative HPLC. Obtained pure phytochemicals were identified by NMR analysis. The influence of the extract and compounds on the cell viability and apoptosis was evaluated by flow cytometry. The release of pro-inflammatory cytokines after LPS stimulation was established by ELISA. Finally, the antimicrobial assays were performed by establishing MIC and MBC values using several bacterial strains. RESULTS The UHPLC analysis revealed the infusion contained mainly, galloyl glucose derivatives, procyanidins and chlorogenic acid. Several compounds were isolated and identified for the first time from the investigated plant material. It was shown that the infusion and its constituents influenced the release of proinflammatory cytokines such as IL-1β, TNF-α and IL-8 and also affected the viability and apoptosis of healthy cells. Both extract and isolated natural products displayed antimicrobial activity against skin pathogens. CONCLUSIONS The results obtained in the present study support that the infusions from common bistort influence key biological processes are crucial for skin conditions with the inflammatory background. The study justifies the traditional topical application of common bistort.
BMC Complementary and Alternative Medicine, Dec 1, 2014
Background: The young shoots of Rubus idaeus are traditionally used as a herbal remedy in common ... more Background: The young shoots of Rubus idaeus are traditionally used as a herbal remedy in common cold, fever and flu-like infections yet there is no research concerning this plant material. The aim of the study was to evaluate the chemical composition and biological properties of raspberry shoots from 11 cultivar varieties. Methods: The methanol extracts were subjected to chromatographic analysis using HPLC-DAD-ESI-MS, and two-dimensional 'comprehensive' LCxLC techniques. The biological activity of the shoot extract from the 'Willamette' cultivar variety was evaluated. Antioxidant activity was tested using DPPH and phosphomolybdenum assay. Antimicrobial activity was estimated towards 15 strains of human pathogenic bacteria using broth microdilution method. Cytotoxic activity was tested using MTT cell viability assay. Results: The dominating compounds identified in the shoots of R. idaeus were ellagic acid (26.1-106.8 mg/100 g) and sanguiin H-6 (139.2-633.1 mg/100 g). The best separation of compounds present in the analysed polyphenol complex, was achieved by 'comprehensive' LCxLC method using Nucleodur Sphinx RP column in the first dimension and Chromolith Performance column in the second dimension. The shoot extract was found to be a strong antioxidant (EC 50 19.4 μg/ml, AAE 427.94 mg/g) and displayed the strongest bactericidal properties towards Corynebacterium diphtheriae. The extract revealed higher cytotoxic activity towards the HL-60 cells (IC 50 110 μg/ml) than HeLa (IC 50 300 μg/ml). Conclusions: The shoots of R. idaeus stand out as a valuable source of sanguiin H-6 and ellagic acid and possess a number of biological properties including antioxidative, antimicrobial and cytotoxic.
European journal of medicinal chemistry, May 1, 2006
Two series of 1-(6-chloro-1,1-dioxo-1,4,2-benzodithiazin-3-yl)-4-arylsemicarbazides 6-17 and 2-ar... more Two series of 1-(6-chloro-1,1-dioxo-1,4,2-benzodithiazin-3-yl)-4-arylsemicarbazides 6-17 and 2-arylamino-8-chloro-5,5-dioxo[1,2,4]triazolo [2,3-b][1,4,2]benzodithiazines 18-26 were prepared in order to evaluate their biological activity. Compounds 6 and 18-26 were tested for their in vitro cytotoxic potency against 12 human cancer cell lines. The compounds 6 and 19 were inactive, whereas triazolobenzodithiazines 18, 20-26 possess tumor growth inhibitory properties. The prominent methyl 8-chloro-2-(4-chlorophenylamino)-5,5-dioxo[1,2,4]triazolo[2,3-b][1,4,2]benzodithiazine-7-carboxylate (21) exhibited potency higher or comparable to cisplatin. Moreover, compounds 6, 9, 19 and 23-25 with structure similar to other chemotherapeutic agents were tested for their antibacterial activity and exhibited MIC and MBC against Staphylococcus aureus (3.9-31.5 μg ml).
tris-[(4,7-diphenyl-1,10-phenanthroline)ruthenium(II)] dichloride (Ru(DPP)3Cl2), a fluorescent se... more tris-[(4,7-diphenyl-1,10-phenanthroline)ruthenium(II)] dichloride (Ru(DPP)3Cl2), a fluorescent sensor which is sensitive to the amount of oxygen in the sample, was applied using the fluorescent optical respirometry (FOR) technique. The oxygen in the samples quenches the fluorescence. The fluorescence intensity depends on the metabolic rate of the viable microorganisms. The effect of DMSO and plant extracts on bacteria was determined by FOR. It was shown that the MIC values obtained by FOR were consistent with the results of the MIC determinations using the method of serial dilutions; at the same time, the effects of concentrations lower than the growth-inhibitory concentrations on microbial cells were demonstrated. The FOR method enables the detection of multiplying bacteria in sterile and non-sterile pharmaceutical preparations in real time, which significantly shortens the time required to obtain results and allows the introduction of repair processes in the production. This metho...
Kalanchoe species are succulents occurring in tropical regions. They have many biological and pha... more Kalanchoe species are succulents occurring in tropical regions. They have many biological and pharmacological properties. In this study, the cytotoxic and antimicrobial activities of water and dichloromethane Kalanchoe fractions obtained from ethanol extracts of three Kalanchoe species—K. daigremontiana, K. pinnata, and K. blossfeldiana were estimated. The cytotoxic effect was assessed on human cancer cell lines—ovarian SKOV-3, cervical HeLa, breast MCF-7, and melanoma A375—by MTT (3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide) assay. The antimicrobial activity was estimated on selected Gram-positive and Gram-negative bacteria strains and on Candida albicans. The phytochemical analysis of selected Kalanchoe extracts was conducted by LC-QTOF-MS. The obtained results showed that the water fraction of K. blossfeldiana was active both on the tested cancer cells (IC50 values were 28.28 ± 2.76 and 32.51 ± 0.69 µg/mL on HeLa and SKOV-3, respectively) and bacteria strains (MI...
The measurement of oxygen consumption is an important element in the understanding of an organism... more The measurement of oxygen consumption is an important element in the understanding of an organism’s metabolic state. Oxygen is also a phosphorescence quencher, which allows the evaluation of phosphorescence emitted by oxygen sensors. Two Ru(II)-based oxygen-sensitive sensors were used to study the effect of chemical compounds [(1) = [CoCl2(dap)2]Cl, and (2) = [CoCl2(en)2]Cl (AmB = amphotericin B) against reference and clinical strains of Candida albicans. The tris-[(4,7-diphenyl-1,10-phenanthroline)ruthenium(II)] chloride ([Ru(DPP)3]Cl2) (Box) adsorbed onto the DavisilTM silica gel was embedded in the silicone rubber Lactite NuvaSil® 5091 and the coating on the bottom of 96-well plates. The water-soluble oxygen sensor (BsOx = tris-[(4,7-diphenyl-1,10-phenanthrolinedisulphonic acid disodium)ruthenium(II)] chloride ‘x’ hydrate = {Ru[DPP(SO3Na)2]3}Cl2 = water molecules were omitted in the BsOx formula) was synthesized and characterized by RP-UHPLC, LCMS, MALDI, elemental analysis, ATR,...
Mangiferin is a strong antioxidant that presents a wide range of biological activities. The aim o... more Mangiferin is a strong antioxidant that presents a wide range of biological activities. The aim of this study was to evaluate, for the first time, the influence of mangiferin on tyrosinase, an enzyme responsible for melanin synthesis and the unwanted browning process of food. The research included both the kinetics and molecular interactions between tyrosinase and mangiferin. The research proved that mangiferin inhibits tyrosinase activity in a dose-dependent manner with IC50 290 +/− 6.04 µM, which was found comparable with the standard kojic acid (IC50 217.45 +/− 2.54 µM). The mechanism of inhibition was described as mixed inhibition. The interaction between tyrosinase enzyme and mangiferin was confirmed with capillary electrophoresis (CE). The analysis indicated the formation of two main, and four less significant complexes. These results have also been supported by the molecular docking studies. It was indicated that mangiferin binds to tyrosinase, similarly to L-DOPA molecule, b...
This article is an open access article distributed under the terms and conditions of the Creative... more This article is an open access article distributed under the terms and conditions of the Creative Commons Attribution (CC BY
This article is an open access article distributed under the terms and conditions of the Creative... more This article is an open access article distributed under the terms and conditions of the Creative Commons Attribution (CC BY
In subtropical regions the extracts from Phyllanthus species are used in the treatment of bacteri... more In subtropical regions the extracts from Phyllanthus species are used in the treatment of bacterial, fungal and parasitic diseases (e.g. P. niruri, P. amarus). Literature data showed that antimicrobial activity of Phyllanthus species results from synergistic effects of occurring secondary metabolites. The MIC and MBC values were determined to show antibacterial activity of extracts from shoot cultures of P. glaucus, P. multiflorus and P. juglandifolius and shoot culture and non-transformed root culture of P. amarus. The dry extracts dissolved in either DMSO or methanol were examined against strains of Gram (+) bacteria – Streptococcus G, S. aureus, S. epidermidis, B. subtilis, C. sporogenes, E. hirae, strains of Gram (-) bacteria – M. catarrhalis, K. pneumoniae, E. coli, P. vulgaris, P. aeruginosa, H. pylori as well as a yeast C. albicans. As controls, the alkaloid securinine, present as a dominant compound of the alkaloid fraction in the shoot culture of P. glaucus, and flavan-3-ol – catechin present in all tested species, were used. Using DMSO to dissolve dry extracts higher MIC values were observed than when dissolved in methanol. The obtained results showed the differences in bacterial susceptibility depending on the Phyllanthus species. For the methanol extracts antimicrobial activity expressed as MIC was in a range from 0.01 mg/mL to 5.0 mg/mL, while the MBC value was determined from 0.01 mg/mL to 10.0 mg/mL. Securinine and catechin were active in a range from 0.03 to 0.25 mg/mL showing the highest activity against Streptococcus G and P. aeruginosa (securinine) and H. pylori (catechin). All extracts and standards were inactive against E. hirae while the most susceptible strain was M. catarrhalis (MBC 0.01 mg/l). Acknowledgement: This Project was supported by the Ministry of Science and Higher Education of the Republic of Poland, from the quality-promoting subsidy, under the Leading National Research Centre (KNOW) programme for the years 2012 – 2017".
Cinnamic acid is a plant metabolite with antimicrobial, anticancer, and antioxidant properties. I... more Cinnamic acid is a plant metabolite with antimicrobial, anticancer, and antioxidant properties. Its synthetic derivatives are often more effective in vitro than parent compounds due to stronger biological activities. In our study, we synthesized ten new N–(4–chloro–2–mercapto–5–methylphenylsulfonyl)cinnamamide derivatives, containing two pharmacophore groups: cinnamic acid moiety and benzenesulfonamide. The antimicrobial activity of the obtained compounds was estimated using different types of Gram-positive and Gram-negative bacteria, fungus species of Candida albicans, as well as clinical strains. The compounds were evaluated on biofilm formation and biofilm formed by Staphylococcus clinical strains (methicillin–resistance S. aureus MRSA and methicillin–resistance coagulase–negative Staphylococcus MRCNS). Furthermore, blood bacteriostatic activity test was performed using S. aureus and S. epidermidis. In cytotoxic study, we performed in vitro hemolysis assay on domestic sheep perip...
Context: Kalanchoe species (Crassulaceae) are widely used in traditional medicine as remedies in ... more Context: Kalanchoe species (Crassulaceae) are widely used in traditional medicine as remedies in infectious diseases and cancer treatment. Objective: Cytotoxic and antimicrobial activities of Kalanchoe daigremontiana Raym.-Hamet & H. Perrier, K. pinnata (Lam.) Pers., and K. blossfeldiana Poelln. extracts were determined. The relationship between biological activities and the extracts bufadienolides content was also investigated. Materials and methods: Fresh leaves of Kalanchoe species were macerated with 95% ethanol or water. The quantitative analysis of bufadienolides in the extracts was carried out with mass spectrometry. Cytotoxicity tests were performed on human cancer cell lines-HeLa, SKOV-3, MCF-7, and A375 by MTT (3-[4,5-dimethylthiazol-2-yl]-2,5-diphenyltetrazolium bromide) assay and Real-Time Cell Analysis system. The microbiological study was done using a few bacteria strains (b-hemolytic Streptococcus, Corynebacterium diphtheriae, Staphylococcus aureus, Staphylococcus epidermidis, Enterococcus hirae, Escherichia coli) and Candida albicans. Results: The K. blossfeldiana ethanol extract and K. daigremontiana water extract exhibited the most potent cytotoxic activity (IC 50 < 19 mg/mL for HeLa and SKOV-3 cells). The strongest antibacterial effects showed ethanol extract of K. blossfeldiana and K. pinnata (MIC values were 8.45, 8.45, 0.25 and <33.75 mg/mL for S. aureus, S. epidermidis, and E. hirae, respectively). The highest total amount of bufadienolides was in K. daigremontiana ethanol extract. In contrast, K. blossfeldiana ethanol extract did not show the presence of these compounds. Conclusions: Kalanchoe blossfeldiana ethanol extract is a potential candidate for cancer and bacterial infection treatment. Additionally, the biological effects of Kalanchoe extracts are not dependent on the presence and amount of bufadienolides in the plant extracts.
Cross-linked polysiloxane microspheres containing a large number of SiOH groups were modified by ... more Cross-linked polysiloxane microspheres containing a large number of SiOH groups were modified by introduction of organic thiol groups, which were further used for the functionalization of the microspheres with silver thiolate groups. The microspheres were characterized by 29 Si MAS NMR, 13 C MAS NMR, SEM, XPS and elemental analysis. They were tested as biocides against selected Gram-positive and Gram-negative bacteria strains and exhibited high bactericidal activity. Separately, linear polysiloxane polymers equipped with organothiol groups and loaded with silver were synthesized. Their antibacterial activity was compared with that of silver thiolate-functionalized microspheres. Different shape of particles and a different form of silver explained somewhat lower activity of polymers.
Journal of Inorganic and Organometallic Polymers and Materials, 2006
Octa(3-chloropropylsilsesquioxane), (T-ClPr) 8 , and a soluble, low molecular weight, poly(3chlor... more Octa(3-chloropropylsilsesquioxane), (T-ClPr) 8 , and a soluble, low molecular weight, poly(3chloropropylsilsesquioxane) were subjected to a reaction with dimethyl-n-octylamine to convert part or almost all the chloropropyl groups to corresponding quaternary ammonium salt (QAS) groups. Polysilsesquioxanes containing secondary n-amylammonium salt (SAS) groups were synthesized by reaction of n-alkyl bromides with poly(3-aminopropylsilsesquioxane) of limited molecular weight or by amination of n-amyl bromide with 3-aminopropyltriethoxysilane followed by hydrolysis and polycondensation. The antibacterial activity of these QASand SAS-containing silsesquioxane materials against two representative Gram-positive and three representative Gram-negative bacterium strains were tested. Most of these materials showed high or moderate activity against Gram-positive bacteria and moderate or weak activity against Gram-negative bacteria.
An analysis of the usefulness of the fluorescence optical respirometry test method to study sever... more An analysis of the usefulness of the fluorescence optical respirometry test method to study several antimicrobials was performed. An oxygen-sensitive sensor: ruthenium-tris(4,7-diphenyl-1,10-phenanthroline) dichloride (Ru(DPP)3Cl2), the phosphorescence of which is quenched by molecular oxygen, was synthesised according to a method modified by us and then applied. A prototype sensitive measurement system was designed and constructed. Analyses of the impact of various antimicrobial chemical factors were performed: ampicillin, co-trimoxazole, nystatin, and newly synthesised compounds. It was shown that optical respirometry allows for analysis of the culture growth kinetics of bacteria and fungi and determination of cell growth parameters. It was shown also that MIC values obtained by fluorescence optical respirometry are consistent with the results of the MIC determinations made by serial dilution method (traditional MIC testing using CLSI). The method allows the time to obtain results...
Journal of Inorganic and Organometallic Polymers and Materials, 2007
Three types of silica particles modified with vinyl groups were obtained: (i) xerogel formed by h... more Three types of silica particles modified with vinyl groups were obtained: (i) xerogel formed by hydrolytic polycondensation of the mixture of tetramethoxysilane (TMOS) and 1,1,1,7-tetramethoxy-3,5,7-trimethyl-3,5,7trivinyltetrasiloxane, (ii) mesoporous silica obtained from the same precursors in the presence of the cetyltrimethylammonium bromide (CTAB), and (iii) commercial Fluka silica gel 60A with a vinyltriethoxysilane-treated surface. Vinyl groups on these silica materials were transformed into silyl chloride by hydrosilylation with HMe 2 SiCl. These groups were used to graft living polysiloxane that was synthesized by anionic ring-opening polymerization of 2,4,6tri(3-chloropropyl)-2,4,6-trimethylcyclotrisiloxane and initiated by BuLi. Chloropropyl groups on the grafted polymer were used to quaternize N,N-dimethyl-n-octylamine. Silica particles with grafted polysiloxane having quaternary ammonium salt (QAS) groups pendant to polymer chains were obtained. Silica material with QAS groups directly attached to the surface were generated by the action of N,Ndimethyl-n-octylamine on particles obtained by the sol-gel process involving tetraethoxysilane (TEOS) with 3-chloropropyltriethoxysilane. The bacteriocidal properties of all these materials were tested in water suspension against five representative strains for Gram-positive and Gram-negative bacteria. Some of the silica-polysiloxane hybrid materials have good antibacterial properties against Gram-positive strains, but not as good as the non-tethered QAS-substituted polysiloxane in water solution. The QAS groups that are directly bonded to the silica material surface are inactive. Keywords Silica hybrids Á Sol-gel silica Á Silica materials Á Functionalized polysiloxanes Á Biocidal polymers Á QAS Á Biocides Á Functionalized silica
Eighteen new 2,6-disubstituted acrylonitriles and two new (benzimidazol-1-yl)-acetamide derivativ... more Eighteen new 2,6-disubstituted acrylonitriles and two new (benzimidazol-1-yl)-acetamide derivatives were prepared and screened for antibacterial and cytotoxic activities on 12 human cancer cell lines. Based on the lead structure 2-(benzimidazol-2-yl)-3-(5-nitrothiophen-2-yl) acrylonitrile it was found that placement of methyl groups at the 5,6 positions of the benzimidazole ring lead to a 3-fold increase in overall cytotoxic activity. Replacing the nitrothiophene for pyridine reduced cytotoxic activity as did replacing the nitro group for a methoxy group. Cytotoxic activity was only slightly reduced when the benzimidazole ring was replaced by a imidazo[4,5-b]pyridine or a benzthiazole ring but replacement by benzoxazole led to a substantial decrease in activity. Moving the acrylonitrile group from position 2 to position 1 of the benzimidazole ring also resulted in moderately active compounds. (Benzimidazol-1-yl)acetamides showed only modest activity. The structure-activity relationships found in the cytotoxicity studies are mirrored in the results of the antibacterial experiments.
An on-line LC-LC-DAD-ESI-MS method was established for quantitation of C-glycosylflavones in fenu... more An on-line LC-LC-DAD-ESI-MS method was established for quantitation of C-glycosylflavones in fenugreek seeds. Anti-Helicobacter pylori activity of standardized 70% methanol extract from fenugreek seeds and vitexin has been demonstrated.
ETHNOPHARMACOLOGICAL RELEVANCE Bistort rhizome (Bistorta officinalis) is a traditionally used pla... more ETHNOPHARMACOLOGICAL RELEVANCE Bistort rhizome (Bistorta officinalis) is a traditionally used plant material popular in Europe and Asia in the treatment of diarrhea and as a topical agent for skin conditions. It contains tannins mostly condensed flavan-3-ol derivatives. However, the in-depth phytochemical investigation of infusions from this plant materials is still lacking. Additionally, the scientific reports supporting the traditional topical application of bistort rhizome are scarce. AIM OF THE STUDY The major objective of the present study was to comprehensively investigate the chemical composition of infusion from subterranean parts of common bistort both using hyphenated chromatographic technique and isolation approach. Additionally, the influence of water extract on pro-inflammatory functions of human neutrophils was performed. As bacterial infections play a crucial role in the generation of skin inflammations the antimicrobial activity of the infusion and its major components was established. MATERIAL AND METHODS The chemical composition of the infusion was established using UHPLC-DAD-MS3 method. Major compounds which could not be identified using chromatographic analysis were isolated by column chromatography and preparative HPLC. Obtained pure phytochemicals were identified by NMR analysis. The influence of the extract and compounds on the cell viability and apoptosis was evaluated by flow cytometry. The release of pro-inflammatory cytokines after LPS stimulation was established by ELISA. Finally, the antimicrobial assays were performed by establishing MIC and MBC values using several bacterial strains. RESULTS The UHPLC analysis revealed the infusion contained mainly, galloyl glucose derivatives, procyanidins and chlorogenic acid. Several compounds were isolated and identified for the first time from the investigated plant material. It was shown that the infusion and its constituents influenced the release of proinflammatory cytokines such as IL-1β, TNF-α and IL-8 and also affected the viability and apoptosis of healthy cells. Both extract and isolated natural products displayed antimicrobial activity against skin pathogens. CONCLUSIONS The results obtained in the present study support that the infusions from common bistort influence key biological processes are crucial for skin conditions with the inflammatory background. The study justifies the traditional topical application of common bistort.
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Papers by Rafał Hałasa