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1.
Heliyon ; 9(12): e22794, 2023 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-38058441

RESUMEN

Fluorescent lighting and optical techniques have been widely utilized to enhance the detection of latent fingerprints. However, the development of new techniques is imperative to expand the range of surfaces from which latent fingerprints can be detected. When relying on traditional methods, fingerprint evidence can remain undetected or even disregarded due to insufficient detection and limited detail, especially when dealing with a luminescent background. In this study, we propose the utilization of optically stimulated luminescence (OSL) applied to a Ba2SiO4 matrix, co-doped with Eu2+ and Dy3+, as a powerful method for visualizing latent fingerprints on various surfaces, including thin plastic bags, rigid duct tape, thin aluminum foil, and glass slices. This technique effectively eliminates any luminescent background and significantly enhances optical imaging. This represents the first successful application of OSL in the development of latent fingerprints, thus paving the way for more efficient and effective forensic techniques in the future.

2.
Anal Chem ; 94(29): 10435-10442, 2022 07 26.
Artículo en Inglés | MEDLINE | ID: mdl-35848818

RESUMEN

The need to find a rapid and worthwhile technique for the in situ detection of the content of delta-9-tetrahydrocannabinol (THC) and cannabidiol (CBD) in Cannabis sativa L. is an ever-increasing problem in the forensic field. Among all the techniques for the detection of cannabinoids, Raman spectroscopy can be identified as the most cost-effective, fast, noninvasive, and nondestructive. In this study, 42 different samples were analyzed using Raman spectroscopy with 1064 nm excitation wavelength. The use of an IR wavelength laser showed the possibility to clearly identify THC and CBD in fresh samples, without any further processing, knocking out the contribution of the fluorescence generated by visible and near-IR sources. The results allow assigning all the Raman features in THC- and CBD-rich natural samples. The multivariate analysis underlines the high reproducibility of the spectra and the possibility to distinguish immediately the Raman spectra of the two cannabinoid species. Furthermore, the ratio between the Raman bands at 1295/1440 and 1623/1663 cm-1 is identified as an immediate test parameter to evaluate the THC content in the samples.


Asunto(s)
Cannabidiol , Cannabinoides , Cannabis , Cannabinoides/análisis , Cannabis/química , Dronabinol/análisis , Reproducibilidad de los Resultados , Espectrometría Raman
3.
Molecules ; 25(9)2020 Apr 28.
Artículo en Inglés | MEDLINE | ID: mdl-32354035

RESUMEN

The reactions of 2,4-bis(4-methoxyphenyl)-1,3-dithio-2,4-diphosphetane-2,4-disulfide (Lawesson's Reagent, LR) with benzylamine (BzNH2) and 4-phenylbutylamine (PhBuNH2) yield benzylammonium P-(4-methoxyphenyl)-N-benzyl-amidodithiophosphonate (BzNH3)(BzNH-adtp) and 4-phenylbutylammonium P-(4-methoxyphenyl)-N-(4-phenylbutyl)-amidodithiophosphonate (PhBuNH3)(PhBuNH-adtp). The relevant nickel complexes [Ni(BzNH-adtp)2] and [Ni(PhBuNH-adtp)2] and the corresponding hydrolysed derivatives (BzNH3)2[Ni(dtp)2] and (PhBuNH3)2[Ni(dtp)2] were prepared and fully characterized. The antimicrobial activity of the aforementioned amidodithiophosphonates against a set of Gram-positive and Gram-negative pathogen bacteria was evaluated, and [Ni(BzNH-adtp)2] and [Ni(PhBuNH-adtp)2] showed antiproliferative activity towards Staphylococcus aureus and Staphylococcus haemolyticus strains. density functional theory (DFT) calculations were performed to shed some light on the activity of reported compounds related to their tendency towards P-N bond cleavage.


Asunto(s)
Antibacterianos/síntesis química , Antibacterianos/farmacología , Química Farmacéutica/métodos , Pruebas de Sensibilidad Microbiana , Níquel/química , Biopelículas/efectos de los fármacos , Candida/efectos de los fármacos , Complejos de Coordinación/química , Diseño de Fármacos , Escherichia/efectos de los fármacos , Hidrólisis , Ligandos , Modelos Moleculares , Nitrógeno/química , Fósforo/química , Pseudomonas/efectos de los fármacos , Teoría Cuántica , Espectroscopía Infrarroja por Transformada de Fourier , Staphylococcus aureus/efectos de los fármacos , Staphylococcus haemolyticus/efectos de los fármacos , Difracción de Rayos X
4.
Front Microbiol ; 8: 2067, 2017.
Artículo en Inglés | MEDLINE | ID: mdl-29114245

RESUMEN

Pistacia lentiscus berry oil (LBO) represents a typical vegetal product of the Mediterranean basin that has been formally used in traditional cuisine for 100s of years. In addition to its interesting alimentary properties, this product could represent an interesting candidate in the field of research on the study of new anti-infective agents. In fact, in Mediterranean countries, lentisk oil still continues to be widely used in folk medicine for oral and skin affections, in particular, acute gingivitis, pediatric skin infections such as impetigo and foot plaques, and biofilm related infections often associated with Streptococcus spp. Following these observations, we have hypothesized a "lentisk oil-bacteria" interaction, placing particular emphasis on the different Streptococcal species involved in these oral and skin diseases. In accordance with this hypothesis, the use of standard antimicrobial-antibiofilm methods (MIC, MBC, MBIC) allowed the interesting behavior of these bacteria to be observed and, in this context, the response to lentisk oil appears to be correlated with the pathogenic profile of the considered microorganism. Two probiotic strains of S. salivarius K12/M18 appeared to be non-sensitive to this product, while a set of five different pathogenic strains (S. agalactiae, S. intermedius, S. mitis, S. mutans, S. pyogenes) showed a response that was correlated to the fatty acid metabolic pathway of the considered species. In fact, at different times of bacteria development, selective High Performance Liquid Chromatography analysis of the growth medium containing LBO detected a significant increase in free unsaturated fatty acids (UFAs) in particular oleic, palmitic and linoleic acids, which are already known for their antibacterial activity. In this context, we have hypothesized that LBO could be able to modulate the pathogen/probiotic rate in a Streptococcal population using the fatty acid metabolic pathway to help the probiotic strain. This hypothesis was strengthened by performing antibacterial testing with oleic acid and an in silico evaluation of the Streptococcal MCRA protein, an enzyme involved in the production of saturated fatty acids from UFA. These results show that LBO may have been used in ancient times as a "natural microbial modulating extract" in the prevention of biofilm- associated diseases.

5.
J Inorg Biochem ; 170: 188-194, 2017 05.
Artículo en Inglés | MEDLINE | ID: mdl-28260677

RESUMEN

The novel heteroleptic cyclometalated complex [AuIII(pyb-H)(mnt)] (1; pyb-H=C-deprotonated 2-benzylpyridine; mnt =1,2-dicyanoethene-1,2-dithiolate) was tested against a panel of ten Gram positive (belonging to the Staphylococcus, Streptococcus spp. and Bacillus clausii), Gram negative (E. coli, K. pneumoniae, P. aeruginosa) bacteria and three yeasts belonging to the Candida spp. Complex 1 showed a remarkable bacteriostatic antimicrobial activity against staphylococci, with Minimum Inhibitory Concentration (MIC) values of 1.56 and 3.13µg/mL for S. haemoliticus and S. aureus, respectively. Spectroscopic and electrochemical measurements, supported by Density Functional Theory (DFT) calculations, were exploited to fully investigate the electronic structure of complex 1 and its relationship with the antimicrobial activity.


Asunto(s)
Antiinfecciosos , Bacterias/crecimiento & desarrollo , Candida/crecimiento & desarrollo , Compuestos Orgánicos de Oro , Antiinfecciosos/síntesis química , Antiinfecciosos/química , Antiinfecciosos/farmacología , Compuestos Orgánicos de Oro/síntesis química , Compuestos Orgánicos de Oro/química , Compuestos Orgánicos de Oro/farmacología
6.
J Colloid Interface Sci ; 448: 320-30, 2015 Jun 15.
Artículo en Inglés | MEDLINE | ID: mdl-25746185

RESUMEN

The ammonium salts of oxamate (AmOxam) and monomethyloxalate (AmMeox), structurally related to ammonium oxalate (AmOx), were synthesized and characterized as protecting agents/filler for calcareous stone substrates. Both compounds featured an improved solubility in water and alcoholic-water mixtures with respect to AmOx. While AmOxam is stable in aqueous solution and reacts with calcite to afford the corresponding insoluble calcium oxamate (CaOxam), AmMeox spontaneously undergoes hydrolysis to give ammonium monohydrogen oxalate hemihydrate (AmBiox) and calcium oxalate (CaOx). Both compounds have been tested for the restoration of naturally weathered marble and biomicritic limestone. The formation of a superficial layer of CaOxam and CaOx was observed on stone samples treated with AmOxam and AmMeox, respectively, depending on the solvent mixture. A quantum-mechanical study was carried out at DFT level in order to investigate the nature of the interactions occurring between the lithic substrate (calcite) and the passivating agents, showing how the structural modifications on oxalic acid derivatives can be exploited to fine-tune their interaction with the calcite surface.

7.
Int J Dent ; 2013: 164267, 2013.
Artículo en Inglés | MEDLINE | ID: mdl-23762059

RESUMEN

The aim of this work is to determine the antibacterial activity of three marketed mouthwashes on suspended and sessile states of Aggregatibacter actinomycetemcomitans. The efficacy of two commonly used products in clinical practice, containing essential oils as active ingredients (menthol, thymol, methyl salicylate, and eucalyptol) in association with or without alcohol, has been evaluated in comparison with a chlorhexidine-based mouthwash. The microtiter plate assay, in order to obtain a spectrophotometric measurement of bacterial responses at growing dilutions of each antiseptic, was used for the study. The analysis revealed that a good antibacterial activity is reached when the abovementioned mouthwashes were used at concentration over a 1/24 dilution and after an exposure time of 30 seconds at least. In conclusion, the alcoholic mouthwash appears to have a better biofilm inhibition than its antiplanktonic activity while the nonalcoholic product demonstrates an opposite effect with a better antiplanktonic behavior.

8.
Open Dent J ; 4: 140-6, 2010 Jul 20.
Artículo en Inglés | MEDLINE | ID: mdl-21113279

RESUMEN

A dental unit water line (DUWL) equipped with a device designed to automatically and continually flush a bacteriostatic solution of hydrogen peroxide (WHE) and a discontinuous disinfecting system (BIOSTER) was evaluated. In the first instance a preliminary sensitivity test on a large number of microorganisms (bacteria and fungi) was tried with a H(2)O(2) range from 100 to 800 ppm. The bacteria frequently reported in DUWL (including Pseudomonas spp, Streptococcus spp., Staphylococcus spp., E. coli) and some periodontal pathogens showed a minimum inhibitory concentration from 100 to 300 H(2)O(2 )ppm (also including M. marinum and C. albicans). However, H(2)O(2) did not show any inhibitory effects against: A. actinomycetemcomitans, C. glabrata C. parapsilos, F. nucleatum, M. micros. In a second step, the DUWL was experimentally infected with S. faecalis, E. coli, P. aeruginosa, S. aureus. After disinfection steps with 3% H(2)O(2), the inhibitory effect on planktonic forms and on sessile biofilm was measured. In a third step, the count of 16S rRNA gene copies by real time PCR at different points of the DUWL described an accrue of bacterial slime in "hot spot" regions characterized by irregular/slow water flux (valves, elbows). However these results suggest that hydrogen peroxide is not only able to inhibit bursts of planktonic bacteria inside the DUWL, but that it could also be effective against sessile biofilm containing heterotrophic microorganisms derived from domestic water line contamination. In addition some oral pathogens could be contaminating and surviving in DUWL.

9.
Nat Prod Res ; 23(2): 190-9, 2009.
Artículo en Inglés | MEDLINE | ID: mdl-19173127

RESUMEN

In this manuscript, the authors compare the chemical composition and the biological effects of extracts of some Sardinian plant species: Glebionis coronaria (L.) Spach [=Chrysanthemum coronarium L.], locally known as 'caragantzu', Glebionis segetum (L.) Fourr. [=Chrysanthemum segetum L.], known as 'caragantzu masedu', and Sardinian endemic species Plagius flosculosus (L.) Alavi and Heywood [=Chrysanthemum flosculosus L.], known as 'caragantzu burdu'. In addition, the authors compare the pyrethrins contained in these species with an extract of Tanacetum cinerariifolium (Trevir.) Sch. Bip. [=Chrysanthemum cinerariifolium (Trevir.) Vis.], a commercial species rich in pyrethrins. The volatile fractions from chrysanthemum flowers were obtained by supercritical fluid extraction (SFE) with CO(2) at 90 bar and 50 degrees C and by hydrodistillation. Pyrethrins were extracted, together with other high molecular mass compounds, by SFE at high pressure, 300 bar and 40 degrees C. The composition of the volatile oils is determined by GC-MS analysis and the amount of pyrethrins by HPLC analysis. Moreover, the antibacterial and antimycotic activities of volatile fractions were investigated in order to compare to their traditional uses.


Asunto(s)
Chrysanthemum cinerariifolium/química , Extractos Vegetales/farmacología , Terpenos/aislamiento & purificación , Terpenos/farmacología , Animales , Antibacterianos/química , Antibacterianos/aislamiento & purificación , Antibacterianos/farmacología , Antifúngicos/química , Antifúngicos/aislamiento & purificación , Antifúngicos/farmacología , Antivirales/química , Antivirales/aislamiento & purificación , Antivirales/farmacología , Supervivencia Celular/efectos de los fármacos , Chlorocebus aethiops , Cromatografía con Fluido Supercrítico , Cromatografía de Gases y Espectrometría de Masas , Células HeLa , Humanos , Italia , Pruebas de Sensibilidad Microbiana , Extractos Vegetales/química , Extractos Vegetales/aislamiento & purificación , Terpenos/química , Células Vero
10.
Fitoterapia ; 80(1): 57-61, 2009 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-18950693

RESUMEN

The essential oils and supercritical CO(2) extracts of wild Daucus carota L. subsp. carota growing spontaneously in Sardinia and in Portugal were investigated. The main components in the Sardinian essential oil of flowering and mature umbels with seeds are beta-bisabolene (17.6-51.0%) and 11-alpha-(H)-himachal-4-en-1-beta-ol (9.0-21.6%); instead, the oils from Portuguese samples are predominantly composed of geranyl acetate (5.2-65.0%) and alpha-pinene (3.5-37.9%). Supercritical extracts contain lower amounts of monoterpenes and higher amounts of sesquiterpene hydrocarbons. Antifungal activities of the Sardinian oils were the highest, particularly for dermatophytes and Cryptococcus neoformans, with MIC values of 0.16-0.64 microL mL(-1).


Asunto(s)
Antifúngicos/farmacología , Daucus carota/química , Hongos/efectos de los fármacos , Aceites Volátiles/farmacología , Extractos Vegetales/farmacología , Terpenos/farmacología , Acetatos/farmacología , Monoterpenos Acíclicos , Monoterpenos Bicíclicos , Flores , Italia , Pruebas de Sensibilidad Microbiana , Sesquiterpenos Monocíclicos , Monoterpenos/farmacología , Aceites Volátiles/química , Aceites Volátiles/aislamiento & purificación , Extractos Vegetales/química , Portugal , Semillas , Sesquiterpenos/aislamiento & purificación , Sesquiterpenos/farmacología
12.
J Agric Food Chem ; 55(24): 10022-7, 2007 Nov 28.
Artículo en Inglés | MEDLINE | ID: mdl-17966976

RESUMEN

The volatile oil of the bark of Cinnamomum zeylanicum was extracted by means of supercritical CO2 fluid extraction in different conditions of pressure and temperature. Its chemical composition was characterized by GC-MS analysis. Nineteen compounds, which in the supercritical extract represented >95% of the oil, were identified. (E)-Cinnamaldehyde (77.1%), (E)-beta-caryophyllene (6.0%), alpha-terpineol (4.4%), and eugenol (3.0%) were found to be the major constituents. The SFE oil of cinnamon was screened for its biological activity about the formation of melanin in vitro. The extract showed antityrosinase activity and was able to reduce the formation of insoluble flakes of melanin from tyrosine. The oil also delayed the browning effect in apple homogenate. (E)-Cinnamaldehyde and eugenol were found to be mainly responsible of this inhibition effect.


Asunto(s)
Cromatografía con Fluido Supercrítico/métodos , Cinnamomum zeylanicum/química , Monofenol Monooxigenasa/metabolismo , Péptidos/análisis , Extractos Vegetales/análisis , Cromatografía de Gases y Espectrometría de Masas , Péptidos/metabolismo , Extractos Vegetales/metabolismo , Presión , Temperatura , Volatilización
13.
Nat Prod Res ; 21(5): 412-7, 2007 May.
Artículo en Inglés | MEDLINE | ID: mdl-17487612

RESUMEN

Supercritical carbon dioxide extraction allowed to obtain the volatile oil of different aerial parts of Ridolfia segetum (L.) Moris. Extraction conditions were as follows: pressure, 90 bar; temperature, 50 degrees C and carbon dioxide flow, Phi = 1.0 kg h(-1). Waxes were entrapped in the first separator set at 90 bar and -10 degrees C. The oil was recovered in the second separator working at 15 bar and 10 degrees C. The main components of the flower oil were alpha-phellandrene (19.4%), terpinolene (20.5%), piperitenone oxide (11.6%), beta-phellandrene (8.2%), (Z)-beta-ocimene (7.8%), myristicin (7.5%) and p-cymene (4.4%). The comparison with the hydrodistilled (HD) oil reveal that the significative difference was the content of sesquiterpenes which are higher in the supercritical fluid extraction (SFE) products. Collection of samples at different extraction times during supercritical extraction, allowed to monitor the change of the oil composition. Lighter compounds, as hydrocarbon monoterpenes, were extracted in shorter times than the heavier hydrocarbon and oxygenated sesquiterpenes. The oil from the steams was characterized by a high content of alpha-phellandrene (12.9%), terpinolene (11.6%), myristicin (11.0%), p-cymene (9.9%), beta-phellandrene (8.2%) and (Z)-beta-ocimene (6.0%) while the main components of the fruits were found to be myristicin (70.8%), piperitenone oxide (19.9%) and dill apiole (4.2%).


Asunto(s)
Apiaceae/química , Cromatografía con Fluido Supercrítico/métodos , Aceites Volátiles/análisis , Extractos Vegetales/análisis , Monoterpenos Acíclicos , Alquenos/análisis , Alquenos/química , Derivados de Alilbenceno , Compuestos de Bencilo/análisis , Compuestos de Bencilo/química , Dióxido de Carbono , Monoterpenos Ciclohexánicos , Cimenos , Dioxolanos/análisis , Dioxolanos/química , Cromatografía de Gases y Espectrometría de Masas , Monoterpenos/análisis , Monoterpenos/química , Aceites Volátiles/química , Aceites Volátiles/aislamiento & purificación , Extractos Vegetales/química , Extractos Vegetales/aislamiento & purificación , Pirogalol/análogos & derivados , Pirogalol/análisis , Pirogalol/química , Sesquiterpenos/análisis , Sesquiterpenos/química , Terpenos/análisis , Terpenos/química
14.
Nat Prod Res ; 21(1): 33-6, 2007 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-17365686

RESUMEN

The aim of this study was to produce Lantana camara essential oil by SFE and to study the effect of matrix grinding on the yield and/or composition of the extract. Experiments were carried out on grinding matrices (G) and on not grinding matrices (NG). The extracts were analyzed by GC-MS. A comparison with the oil obtained by hydrodistillation is also given. Finally, the antibacterial and antifungal activity of the various extracts has been assayed.


Asunto(s)
Antibacterianos/aislamiento & purificación , Antifúngicos/aislamiento & purificación , Lantana/química , Aceites Volátiles/aislamiento & purificación , Aceites de Plantas/aislamiento & purificación , Antibacterianos/química , Antibacterianos/farmacología , Antifúngicos/química , Antifúngicos/farmacología , Cromatografía con Fluido Supercrítico , Cromatografía de Gases y Espectrometría de Masas , Humanos , Pruebas de Sensibilidad Microbiana , Aceites Volátiles/química , Aceites Volátiles/farmacología , Hojas de la Planta/química , Aceites de Plantas/química , Aceites de Plantas/farmacología
15.
Nat Prod Res ; 20(9): 820-6, 2006 Jul 20.
Artículo en Inglés | MEDLINE | ID: mdl-16753919

RESUMEN

Isolation of the volatile concentrate from dried leaves of Seseli bocconi Guss. subsp. praecox Gamisans were obtained by supercritical fluid extraction (SFE) with carbon dioxide. Leaves from different zones of Sardinia (Italy) were collected and treated. Compositions of samples were analyzed by GC-MS. The volatile concentrate of S. bocconi from Buggerru was found to contain: himachalol (16.4%), sabinene (14.8%), beta-phellandrene (8.1%), cis-sabinene hydrate (4.5%). beta-Phellandrene (29.2%), undecane (9.6%), alpha-pinene (6.1%) and beta-guaiene (5.7%) were the main constituents of the volatile extract of S. bocconi from Carloforte. The volatile concentrate of S. bocconi of Ogliastra inland, was composed chiefly by alpha-humulene (17.7%), gamma-himachalene (9.3%), beta-phellandrene (8.0) and bicyclogermacrene (7.7%). The yields of extraction were in the range (0.13-0.60%). A comparison with the hydrodistilled oil revealed in each case a remarkable difference in composition.


Asunto(s)
Apiaceae/química , Aceites Volátiles/química , Terpenos/aislamiento & purificación , Animales , Dióxido de Carbono/química , Chlorocebus aethiops , Cromatografía con Fluido Supercrítico/métodos , Cromatografía de Gases y Espectrometría de Masas , Pruebas de Sensibilidad Microbiana , Aceites Volátiles/aislamiento & purificación , Aceites Volátiles/farmacología , Terpenos/química , Terpenos/farmacología , Células Vero
16.
Nat Prod Res ; 20(5): 455-9, 2006 May 10.
Artículo en Inglés | MEDLINE | ID: mdl-16644543

RESUMEN

Dried and ground leaves of lemon grass (Cymbopogon citratus Stapf.) were used as a matrix for supercritical extraction of essential oil with CO(2). The objective of this study was to analyze the influence of pressure on the supercritical extraction. A series of experiments were carried out, for 360 min, at 50 degrees C and at different pressures: 90, 100, 110 and 120 bar. Extraction conditions were chosen to maximize citral content in the extract oil. The collected extracts were analysed by GC-MS and their composition was compared with that of the essential oil isolated by hydrodistillation and by steam distillation. At higher solvent density the extract aspect changes passing from a characteristic yellow essential oil to yellowish semi-solid mass because of the extraction of high molecular mass compounds. The optimum conditions for citral extraction were 90 bar and 50 degrees C, at these conditions citral represent more than 68% of the essential oil and the extraction yield was 0.65% while the yield obtained from hydrodistillation was 0.43% with a content of citral of 73%.


Asunto(s)
Cymbopogon , Fitoterapia , Extractos Vegetales/química , Aceites de Plantas/química , Dióxido de Carbono/química , Cromatografía con Fluido Supercrítico , Humanos , Hojas de la Planta
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