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1.
Molecules ; 29(5)2024 Feb 21.
Artigo em Inglês | MEDLINE | ID: mdl-38474462

RESUMO

Both geraniol and the products of its transformation, thanks to their beneficial properties, find a variety of applications in cosmetics. Due to their antioxidant and moisturizing properties, these compounds can be added to skin care products such as face creams, lotions, oils, and masks. In addition, these compounds show some antibacterial and antifungal properties, making them suitable for application in skin care products to help fight against bacteria or fungi. This study determined the antimicrobial activity of geraniol and the compounds which were formed during its transformation in relation to selected Gram-positive bacteria, and the preliminary assessment was made whether these compounds can act as ingredients of preparations with potential antimicrobial activity in the treatment of various human diseases (for example diseases of the skin, digestive system, or urinary tract). In addition, this work presents studies on the microbiological purity of cream samples obtained with different contents of geraniol and its transformation products (contents of the tested compounds: 0.5%, 1.5%, 2.5%, 4%, 8%, and 12%). Antibacterial activity tests were performed using the disc diffusion method against Gram-positive cocci, including the reference strains Staphylococcus aureus ATCC 29213 and Enterococcus faecalis ATCC 29212, and against the clinical strains Staphylococcus aureus MRSA, Staphylococcus epidermidis, Enterococcus faecalis VRE VanB, Enterococcus faecium VRE VanA, and Enterococcus faecium VRE VanB. The most active ingredient against bacteria of the Staphylococcus genus was citral, followed by linalool and then geraniol. During our tests, in the case of bacteria of the Enterococcus genus, citral also showed the highest activity, but linalool, ocimenes, and geraniol showed a slightly lower activity. Moreover, this study examined the microbiological purity of cream samples obtained with various contents of geraniol and its transformation products. In the tests of the microbiological purity of cream samples, no growth of aerobic bacteria and fungi was found, which proves the lack of microbiological contamination of the obtained cosmetic preparations. On this basis, it was assessed that these compounds have preservative properties in the prepared creams. The addition of the analyzed compounds also had influence on the durability of the creams and had no effect on the change in their consistency, did not negatively affect the separation of phases during storage, and even had a positive effect on organoleptic sensations by enriching the smell of the tested samples.


Assuntos
Monoterpenos Acíclicos , Antibacterianos , Enterococcus faecium , Humanos , Bactérias Gram-Positivas , Testes de Sensibilidade Microbiana
2.
Postepy Dermatol Alergol ; 40(5): 592-598, 2023 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-38028421

RESUMO

Morphea en coup de sabre and progressive hemifacial atrophy are extremely rare connective tissue disorders causing facial deformity. In extreme cases, morphological disorders are accompanied by symptoms of a clear impairment of the stomatognathic system. The aetiology of the above-mentioned diseases is still unknown. Properly planned therapy in the field of maxillofacial orthopaedics makes it possible to correct the asymmetric pattern of hard tissue growth and thus enable rehabilitation. The task of augmentation techniques is the volumetric supplementation of tissue defects resulting from atrophic processes. The degree of destruction and the extent of changes determine the method of correction. Mild and moderate defects are treated mainly with biomaterials and autologous adipose tissue. The severe course of hemifacial atrophy and morphea en coup de sabre and the associated significant tissue atrophy necessitate the search for more complex methods of treatment. In this paper, we summarize the disturbances of the stomatognathic system in patients with craniofacial morphea, together with an analysis of current treatment options.

3.
Molecules ; 27(24)2022 Dec 10.
Artigo em Inglês | MEDLINE | ID: mdl-36557901

RESUMO

The results of a study on the epoxidation of 1,5,9-cyclododecatriene (CDT) on a W-SBA-15 catalyst using the batch and half-periodic methods are presented. During this study, the activity of the W-SBA-15 catalyst was compared to that of the Ti-SBA-15 catalyst, and the W-SBA-15 catalyst was found to be about 20 times more active than the Ti-SBA-15 catalyst. The highest CDT conversion so far, amounting to 86 mol%, was obtained after carrying out the 4 h epoxidation process. Conducting the studied process using the semi-batch method did not result in the significant improvement in value functions describing this process (CDT conversion and selectivity of CDT transformation to ECDD), but the fastest H2O2 dosing rate (246 µL/h) allowed us to obtain 9 mol% higher CDT conversion in comparison to the batch method.


Assuntos
Peróxido de Hidrogênio , Dióxido de Silício , Catálise
4.
Molecules ; 27(20)2022 Oct 18.
Artigo em Inglês | MEDLINE | ID: mdl-36296608

RESUMO

This work presents a literature review on the biological activity of S-carvone, geraniol and derivatives of these compounds, which are formed in the process of isomerization (during the process of geraniol isomerization, oxidation products of this compound are also obtained). Moreover, this work presents preliminary microbiological tests of creams with the addition of these biologically active compounds: S-carvone, geraniol, carvacrol (an S-carvone isomerization product), nerol (a geraniol isomerization product), linalool (a geraniol isomerization product) and citral (a geraniol oxidation product). Because the post-reaction mixture obtained after the S-carvone isomerization has a relatively simple composition, it was also added to creams and tested without isolating pure compounds. This may be a cheaper alternative to creams prepared with the addition of pure compounds. The mixture obtained after the geraniol isomerization process has a very complex composition; therefore, only compounds with the lowest molecular weight and are easily commercially available were selected for studies. The content of the tested compounds in the creams ranged from 0.5 to 3 wet%. The following microorganisms were selected for microbiological tests: the Gram-negative bacterium Escherichia coli K12, the Gram-positive bacterium Staphylococcus epidermidis, and the fungi Candida albicans, Trichophyton rubrum, Aspergillus niger, and Penicillium chrysogenum. A content of 3% carvacrol, nerol, geraniol and citral inhibited the growth of E. coli, and attenuated the growth of C. albicans and T. rubrum. On the other hand, 3% carvacrol and citral only poorly attenuated the growth of the mould fungi P. chrysogenum and A. niger.


Assuntos
Monoterpenos , Terpenos , Monoterpenos/farmacologia , Terpenos/farmacologia , Isomerismo , Escherichia coli , Aspergillus niger
5.
J Cosmet Sci ; 70(3): 137-147, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31398102

RESUMO

The antimicrobial properties of natural limonene and the compounds obtained after isomerization of limonene (α-terpinene, γ-terpinene, terpinolene, and p-cymene) were studied. The following microorganisms were selected for the tests: Gram-negative bacteria Escherichia coli K12 (ACCT 25922), Gram-positive Staphylococcus epidermidis (ACCT 49461), yeast fungi Candida albicans, and fungi Trichophyton rubrum, Aspergillus niger, Penicillium commune, Trichoderma viride, and Cladosporium cladosporioides. During the studies, terpinolene showed the highest activity, and therefore, this compound was chosen for the preparation of therapeutic creams (content of terpinolene: 0.5 and 2 wt%). The obtained creams were active in the microbiological tests even at the lowest content of terpinolene. The mixture of products obtained after the isomerization of limonene also showed antimicrobial activity. Probably, in the future, this mixture of products can be used as a potential and relatively inexpensive ingredient in therapeutic and protective creams that can be applied for the relief of skin lesions and in the treatment of acne or atopic dermatitis.


Assuntos
Limoneno/química , Catálise , Monoterpenos Cicloexânicos , Cimenos , Isomerismo , Monoterpenos , Dióxido de Silício , Terpenos
6.
Ginekol Pol ; 89(2): 68-73, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29512810

RESUMO

OBJECTIVES: HIV-positive women are at increased risk of HPV infection and cervical cancer. European and national guidelines advise yearly screening for cervical cancer, however due to the lack of a central registration of HIV infected persons there is a gap in offering such care through general healthcare services in many countries, including Poland. MATERIAL AND METHODS: In response to the above limitations, integrated gynaecological care (IGC) was established at the HIV Out-Patient Clinic in Warsaw. We analysed data from January 2007 to May 2014. Logistic regression models were used to identify factors associated with not using IGC by patients. RESULTS: Two hundred and forty women were registered in the observation period:59.6% infected through sexual contact, 18.7% through IDUs, 19.2 % through unknown causes and 2.5% by other (two were vertically infected). The median follow-up time was 2.35 (IQR 0.9-4.5) years and 78.3% were on combination antiretroviral therapy (cART). In total 145 of the women (60.4%) used IGC, from 72.1% of those registered in 2007 to 27.3% registered in 2014. There were in total 1075 gynaeco-logical visits and 254 cervical cytology tests performed. Seventy-five (51.7%) women were tested for HPV infection. Fac-tors decreasing the odds of not using IGC identified by multivariate regression models were being on cART (OR 0.25 [IQR: 0.10-0.59]; p = 0.003) and longer time of observation (0.69 [0.58-0.83]; p = 0.0001). CONCLUSIONS: The utilisation of IGC was very high, but with a delay in commencing the IGC. Women on cART and with longer periods of follow-up had lower odds of not using IGC. A screening approach for women not yet on cART, or newly registered in the clinics, needs special attention.


Assuntos
Atenção à Saúde/métodos , Detecção Precoce de Câncer/estatística & dados numéricos , Soropositividade para HIV , Aceitação pelo Paciente de Cuidados de Saúde/estatística & dados numéricos , Neoplasias do Colo do Útero/diagnóstico , Adulto , Fármacos Anti-HIV/uso terapêutico , Quimioterapia Combinada , Feminino , Soropositividade para HIV/diagnóstico , Soropositividade para HIV/tratamento farmacológico , Humanos , Polônia , Fatores de Tempo
8.
Molecules ; 19(12): 19907-22, 2014 Nov 28.
Artigo em Inglês | MEDLINE | ID: mdl-25460313

RESUMO

Limonene belongs to a group of very important intermediates used in the production of fine chemicals. This monoterpene compound can be obtained from peels of oranges or lemon which are a (biomass) waste from the orange juice industry. Thus, limonene is a renewable, easy available and a relatively cheap compound. This work presents preliminary studies on the process of limonene epoxidation over zeolite type catalysts such as: TS-1 and Ti-SBA-15. In these studies methanol was used as a solvent and as an oxidizing agent a 60 wt % hydrogen peroxide solution was applied. The activity of each catalyst was investigated for four chosen temperatures (0 °C, 40 °C, 80 °C and 120 °C). The reaction time was changed from 0.5 to 24 h. For each catalyst the most beneficial conditions (the appropriate temperature and the reaction time) have been established. The obtained results were compared and the most active catalyst was chosen. These studies have also shown different possible ways of limonene transformation, not only in the direction of 1,2-epoxylimonene and its corresponding diol, but also in direction of carveol, carvone and perillyl alcohol-compounds with a lot of applications. The possible mechanisms of formation of the allylic oxidation products were proposed.


Assuntos
Cicloexenos/química , Compostos de Epóxi/química , Silicatos/química , Dióxido de Silício/química , Terpenos/química , Titânio/química , Catálise , Monoterpenos Cicloexânicos , Limoneno , Monoterpenos/química , Oxirredução , Temperatura , Fatores de Tempo
9.
J Phys Chem A ; 117(38): 9156-67, 2013 Sep 26.
Artigo em Inglês | MEDLINE | ID: mdl-23987792

RESUMO

Absorption and emission spectroscopic investigations and computational predictions have shown that neutral molecules of flavonols and diflavonols can exist in the ground and excited states in one or two tautomeric forms stabilized by intramolecular (in aprotic media) or intermolecular (with solvent molecule(s), in protic media) hydrogen bonds. Electronic excitation creates conditions for the transformation of tautomeric forms, accompanied by proton transfer, reflected in fluorescence spectra. Proton transfer is also probable in monoanions of diflavonols in protic media. The OH groups involved in hydrogen bonds exhibit a proton-donating ability characterized by the respective acidity constants. The electronically excited diflavonols are relatively strong acids if they lose one proton. With increasing basicity of the medium, anionic forms occur, which exhibit spectral characteristics and emission abilities different from those of neutral molecules. These features open up possibilities for the analytical use of these compounds as spectral probes sensitive to the properties of liquid phases--from neutral to strongly basic. The less intensively studied diflavonols seem to be more promising than flavonols for these purposes, since they are more lipophilic, polarizable, polar, and sensitive to basic features of the environment.


Assuntos
Flavonóis/química , Modelos Moleculares , Análise Espectral , Absorção , Fenômenos Químicos , Concentração de Íons de Hidrogênio , Isomerismo , Luz , Conformação Molecular , Termodinâmica
10.
RSC Adv ; 13(43): 30281-30292, 2023 Oct 11.
Artigo em Inglês | MEDLINE | ID: mdl-37849709

RESUMO

In this study, the catalytic performance of Ti3C2 MXene materials in the reaction of α-pinene isomerization was demonstrated. The influence of etching agents (HF, HF/H2SO4, and HF/HCl; weight ratios of mixed acids: 1 : 3, 1 : 4, and 1 : 5) on removing Al atoms from MAX phase, creation of an accordion-like structure typical for MXenes and catalytic activity of the produced samples have been revealed. The MXene HF obtained by MAX phase HF treatment exhibited the highest activity (conversion of α-pinene 74.65 mol%), while materials produced with the mixed acids (HF/H2SO4 and HF/HCl) showed a significant reduction in the conversion of α-pinene (on average about 28-fold). However, these last samples displayed an increase of about 10 mol% in the selectivity to the most desirable product-camphene. The high activity of MXene HF is a result of a high concentration of acid sites (11.62 mmol g-1) - the concentration of acid sites in the samples obtained by MAX phase mixed acids treatment was about 2.5-5.5 times smaller. This work proposes possible mechanisms for the α-pinene isomerization reaction on the MXene HF and on the MXene HF/H2SO4X : Y and MXene HF/HCl X : Y in connection with their structure.

11.
Materials (Basel) ; 16(3)2023 Feb 02.
Artigo em Inglês | MEDLINE | ID: mdl-36770273

RESUMO

The thermal properties of pavement layers made of concrete with varying bulk densities are a particularly interesting topic in the context of development road technologies. If a hybrid layer system is used as a starting point, with thin asphalt layers (from 1 cm to 4 cm) laid on top of a foam concrete layer, thermal properties begin to play a crucial role. The main research problem was to create a test method enabling the assessment of the influence of solar heating on the thermal parameters of the building material, especially cement concrete. For this reason, this paper is concerned specifically with the assessment of a new methodology for testing and calculating the value of the thermal diffusivity coefficient of samples made of concrete varying bulk densities. In this case, using the proprietary concept the authors built a solar simulator using a multi-source lighting system. The analysis of the results of laboratory tests and numerical analyses allowed the authors to observe that there is a strong correlation between the bulk density of samples heated and the thermal diffusivity parameter, which appears in the unidirectional heat transfer equation. The strength of this relationship has been expressed with the coefficient of determination and amounts to 99%. The calculated values of the coefficient of thermal diffusivity for samples made of foam concrete range from 0.16×10-6m2s to 0.52×10-6m2s and are lower (from 2.5 to 8 times) than the value determined for samples made of typical cement concrete.

12.
Artigo em Inglês | MEDLINE | ID: mdl-37329374

RESUMO

In the era of ecology and careful care for the environment, it becomes important to use renewable raw materials of plant origin, which are often more easily available and cheaper. One of the important and rapidly developing directions of research are works related to the use of waste plant biomass; an example of this trend is the production of activated carbons from food industry waste. One of the examples of the application of derived from biomass activated carbons can be using them as catalysts for the isomerization of terpene compounds. Carbons based on waste biomass are characterized by the minimal amount of waste formation during their manufacture, and their use in the isomerization reaction allows to obtain high conversion of organic raw material and high selectivities of transformation to the desired products, making these carbons environmentally friendly substitutes for the catalysts used usually in this process. In this work, obtained carbonaceous catalysts were tested in the process of isomerization of α-pinene to high value chemicals (mainly camphene and limonene). Under the most favorable conditions (activated carbon from sunflower husks content in reaction mixture 5 wt%, temperature 180 °C, and reaction time 100 min), α-pinene was completely converted (conversion 100 mol%) with high selectivity towards camphene (54 mol%). To prepare activated carbons, biomass precursors (orange peels, sunflower husks, spent coffee grounds) were activated with 85% H3PO4 through the chemical activation. The obtained materials were characterized by such methods as sorption N2 at - 196 °C, X-ray diffraction (XRD), Fourier-transform infrared spectroscopy (FTIR), scanning electron microscope (SEM), and X-ray fluorescence (XRF) to determine the relationship between their textural-chemical properties and catalysts activity in isomerization process. The synthesized materials were characterized by a specific surface area in the range of 930-1764 m2, total pore volume in the range of 0.551-1.02 cm3/g, and total acid-site concentrations in the range of 1.47-2.33 mmol/g. These results showed that textural parameters of the obtained activated carbons have the important role in the isomerization of α-pinene.

13.
Materials (Basel) ; 15(7)2022 Mar 26.
Artigo em Inglês | MEDLINE | ID: mdl-35407782

RESUMO

This article presents research related to the transformation of geraniol (GA), leading to the formation of products with very valuable properties. In the planned method, heterogeneous catalysts of natural origin in the form of alum and diatomite were used as catalysts. Initially, the process which we investigated was the process of isomerization of GA, but it turned out during the studies that GA is also transformed in other reactions. Before catalytic tests, these two minerals were subjected to detailed instrumental analyses using the following methods: XRD, SEM/EDX, XRF and FTIR, which allowed to obtain their full morphological characteristics. During the catalytic tests, the influence of such relevant parameters on the GA transformations was determined: temperature from 80 to 150 °C, catalyst content from 5 to 15% by weight and the reaction time from 15 min to 24 h. The tests presented in the article were carried out under atmospheric pressure (in air) as well as without the use of a solvent. The optimal conditions for the transformations of GA were determined on the basis of its conversion and selectivities of transformation to the main products in the form of: beta-pinene (BP), 6,11-dimethyl-2,6,10-dodecatriene-1-ol (DC) and thumbergol (TH). The above products were formed with the highest selectivity, respectively: 100 mol%, 50 mol% and 52 mol%. The results of the syntheses showed that for GA the best transformation results were obtained at the temperature of 80 °C (for both tested catalysts), with the catalyst content of 1 wt % (for both tested catalysts) and for the reaction time of 1 h (for diatomite)) and 3 h (for alum).

14.
J Org Chem ; 76(4): 1072-85, 2011 Feb 18.
Artigo em Inglês | MEDLINE | ID: mdl-21247186

RESUMO

10-Methyl-9-(phenoxycarbonyl)acridinium trifluoromethanesulfonates bearing alkyl substituents at the benzene ring were synthesized, purified, and identified. In the reaction with OOH(-) in basic aqueous media, the cations of the compounds investigated were converted to electronically excited 10-methyl-9-acridinone, whose relaxation was accompanied by chemiluminescence (CL). The kinetic constants of CL decay, relative efficiencies of light emission, chemiluminescence quantum yields, and resistance toward alkaline hydrolysis were determined experimentally under various conditions. The mechanism of CL generation is considered on the basis of thermodynamic and kinetic parameters of the reaction steps predicted at the DFT level of theory. The chemiluminescence efficiency is the result of competition of the electrophilic center at C(9) between nucleophilic substitution by OOH(-) or OH(-) and the ability of the intermediates thus formed to decompose to electronically excited 10-methyl-9-acridinone. Identification of stable and intermediate reaction products corroborated the suggested reaction scheme. The results obtained, particularly the dependency of the "usefulness" parameter, which takes into account the CL quantum yield and the susceptibility to hydrolysis, on the cavity volume of the entity removed during oxidation, form a convenient framework within which to rationally design chemiluminescent 10-methyl-9-(phenoxycarbonyl)acridinium cations.

15.
Wiad Lek ; 64(2): 75-8, 2011.
Artigo em Inglês | MEDLINE | ID: mdl-22026269

RESUMO

The study concerns determination of disturbances of the oxidative-antioxidative balance in patients with heart failure. The study group consisted of 37 patients, having the average age of 42.3 +/- 12.3 years, suffering from idiopathic or inflammatory heart failure. The patients have been qualified as degree II/III in accordance with NYHA scale. A statistically significant increase of anty-oxLDL level (254.28 +/- 80.79 vs 196.64 +/- 83.11 mU/ml; p<0.01) and malondialdehyde level (4.86 +/- 1.74 vs 3.71 +/- 1.19 micromol/l; p<0.05) has been demonstrated after 6-month observation. No statistically significant differences have been found for the activity of total superoxide dismutase (SOD) and its isoenzymes--(SOD-Mn) and (SOD-ZnCu). The results of the study indicate that no changes in SOD activity and increase in lipid peroxidation products level may lead to generation of oxidative stress may play an important role in the pathogenesis of heart failure.


Assuntos
Insuficiência Cardíaca/metabolismo , Peroxidação de Lipídeos , Superóxido Dismutase/metabolismo , Adulto , Catalase/metabolismo , Feminino , Humanos , Lipoproteínas LDL/metabolismo , Masculino , Malondialdeído/metabolismo , Estresse Oxidativo
16.
Materials (Basel) ; 14(24)2021 Dec 16.
Artigo em Inglês | MEDLINE | ID: mdl-34947400

RESUMO

The work presents the results of studies on α-pinene oxidation over the TS-1 catalysts with different Ti content (in wt%): TS-1_1 (9.92), TS-1_2 (5.42), TS-1_3 (3.39) and TS-1_4 (3.08). No solvent was used in the oxidation studies, and molecular oxygen was used as the oxidizing agent. The effect of titanium content in the TS-1 catalyst, temperature, reaction time and amount of the catalyst in the reaction mixture on the conversion of α-pinene and the selectivities of appropriate products was investigated. It was found that it is most advantageous to carry out the process of α-pinene oxidation in the presence of the TS-1 catalyst with the titanium content of 5.42 wt% (TS-1_2), at the temperature of 85 °C, for 6 h and with the catalyst TS-1 content in the reaction mixture of 1 wt%. Under these conditions the conversion of α-pinene amounted to 34 mol%, and the selectivities of main products of α-pinene oxidation process were: α-pinene oxide (29 mol%), verbenol (15 mol%) and verbenone (12 mol%). In smaller quantities also campholenic aldehyde, trans-pinocarveol, myrtenal, myrtenol, L-carveol, carvone and 1,2-pinanediol were also formed. These products are of great practical importance in food, cosmetics, perfumery and medicine industries. Kinetic studies were also performed for the studied process.

17.
Materials (Basel) ; 14(24)2021 Dec 14.
Artigo em Inglês | MEDLINE | ID: mdl-34947323

RESUMO

The work presents the synthesis of FeCl3-modified carbonaceous catalysts obtained from waste orange peel and their application in the oxidation of alpha-pinene in solvent-free reaction conditions. The use of waste orange peel as presented here (not described in the literature) is an effective and cheap way of managing this valuable and renewable biomass. FeCl3-modified carbonaceous materials were obtained by a two-stage method: in the first stage, activated carbon was obtained, and in the second stage, it was modified by FeCl3 in the presence of H3PO4 (three different molar ratios of these two compounds were used in the studies). The obtained FeCl3-modified carbon materials were subjected to detailed instrumental studies using the methods FT-IR (Fourier-transform Infrared Spectroscopy), XRD (X-ray Diffraction), SEM (Scanning Electron Microscope), EDXRF (Energy Dispersive X-ray Fluorescence) and XPS (X-ray Photoelectron Spectroscopy), while the textural properties of these materials were also studied, such as the specific surface area and total pore volume. Catalytic tests with the three modified activated carbons showed that the catalyst obtained with the participation of 6 M of FeCl3 and 3 M aqueous solutions of H3PO4 was the most active in the oxidation of alpha-pinene. Further tests (influence of temperature, amount of catalyst, and reaction time) with this catalyst made it possible to determine the most favorable conditions for conducting oxidation on this type of catalyst, and allowed study of the kinetics of this process. The most favorable conditions for the process were: temperature of 100 °C, catalyst content of 0.5 wt% and reaction time 120 min (very mild process conditions). The conversion of the organic raw material obtained under these conditions was 40 mol%, and the selectivity of the transformation to alpha-pinene oxide reached the value of 35 mol%. In addition to the epoxy compound, other valuable products, such as verbenone and verbenol, were formed while carrying out the process.

18.
Materials (Basel) ; 14(24)2021 Dec 17.
Artigo em Inglês | MEDLINE | ID: mdl-34947405

RESUMO

DT0-activated carbons modified with HCl and HNO3 acids, which were used for the first time in the catalytic process of alpha-pinene isomerization, are presented in this study. The carbon materials DT0, DT0_HCl, DT0_HNO3, and DT0_HCl_HNO3 were examined with the following methods: XRF, SEM, EDX, XPS, FT-IR, XRD, and N2 adsorption at -196 °C. It was shown that DT0_HCl_HNO3-activated carbon was the most active material in the alpha-pinene isomerization process. Detailed studies of alpha-pinene isomerization were carried out over this carbon by changing the reaction parameters such as time (5-180 min) and temperature (60-175 °C). The 100% conversion of alpha-pinene was achieved at the temperature of 160 °C and catalyst content of 5 wt% after 3 h over the DT0_HCl_HNO3 catalyst. Camphene and limonene were the main products of the alpha-pinene isomerization reaction.

19.
Materials (Basel) ; 14(23)2021 Dec 04.
Artigo em Inglês | MEDLINE | ID: mdl-34885604

RESUMO

This work presents studies on the preparation of porous carbon materials from waste biomass in the form of orange peels, coffee grounds, and sunflower seed husks. The preparation of activated carbons from these three waste materials involved activation with KOH followed by carbonization at 800 °C in an N2 atmosphere. This way of obtaining the activated carbons is very simple and requires the application of only two reactants. Thus, this method is cheap, and it does not generate much chemical waste. The obtained activated carbons were characterized by XRD, SEM, XPS, and XRF methods. Moreover, the textural properties, acidity, and catalytic activity of these materials were descried. During catalytic tests carried out in the alpha-pinene isomerization process (the use of the activated carbons thus obtained in the process of alpha-pinene isomerization has not been described so far), the most active were activated carbons obtained from coffee grounds and orange peels. Generally, the catalytic activity of the obtained materials depended on the pore size, and the most active activated carbons had more pores with sizes of 0.7-1.0 and 1.1-1.4 nm. Moreover, the presence of potassium and chlorine ions in the pores may also be of key importance for the alpha-pinene isomerization process. On the other hand, the acidity of the surface of the tested active carbons did not affect their catalytic activity. The most favorable conditions for carrying out the alpha-pinene isomerization process were the same for the three tested activated carbons: temperature 160 °C, amount of the catalyst 5 wt.%, and reaction time 3 h. Kinetic studies were also carried out for the three tested catalysts. These studies showed that the isomerization over activated carbons from orange peels, coffee grounds, and sunflower seed husks is a first-order reaction.

20.
Cancers (Basel) ; 13(1)2020 Dec 23.
Artigo em Inglês | MEDLINE | ID: mdl-33374674

RESUMO

Current knowledge on the biology of squamous cell vulvar carcinoma (VSCC) is limited. We aimed to identify protein markers of VSCC tumors that would permit to stratify patients by progression risk. Early-stage tumors from patients who progressed (progVSCC) and from those who were disease-free (d-fVSCC) during follow-up, along with normal vulvar tissues were examined by mass spectrometry-based proteomics. Differentially expressed proteins (DEPs) were then verified in solid tissues and blood samples of patients with VSCC tumors and vulvar premalignant lesions. In progVSCC vs. d-fVSCC tumors, the immune response was the most over-represented Gene Ontology category for the identified DEPs. Pathway profiling suggested bacterial infections to be linked to aggressive VSCC phenotypes. High Mobility Group AT-Hook 2 (HMGA2) and Proteinase 3 (PRTN3) were revealed as proteins predicting VSCC progression. HMGA2 and PRTN3 abundances are associated with an aggressive phenotype, and hold promise as markers for VSCC patient stratification. It appears that vulvovaginal microflora disturbances trigger an inflammatory response contributing to cancer progression, suggesting that bacterial rather than viral infection status should be considered in the development of targeted therapies in VSCC.

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