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1.
PLoS One ; 17(6): e0267129, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35767534

RESUMEN

We hereby investigate the pitch used for coating three Roman amphorae from San Felice Circeo (Italy) through a multidisciplinary study. The identification of molecular biomarkers by gas chromatography-mass spectrometry is combined with archaeobotanical evidence of pollen and plant tissues of Vitis flowers. Diterpenic chemical markers together with Pinus pollen and wood revealed Pinaceae tar coating. Aporate 3-zonocolpate pollen, identified as Vitis, together with tartaric, malic and pyruvic acids elucidate the grape-fermented nature of the content. Our conclusions open new consideration on the use of grape derivatives that cannot be supported by traditional analytical methods. Based on the finds of aporate Vitis pollen, found also in local modern and Middle Pleistocene samples, we hypothesize the use of autochthonous vines. The presence of a medicinal wine (historically reported as oenanthium) is also considered. We interrogate Vitis pollen capacity to target grapevine domestication, thereby providing innovative tools to understand such an important process. We anticipate our study to encourage a more systematic multidisciplinary approach regarding the analyses of wine amphorae.


Asunto(s)
Vitis , Vino , Flores/química , Cromatografía de Gases y Espectrometría de Masas , Fenoles/análisis , Vitis/química , Vino/análisis
2.
Molecules ; 27(5)2022 Feb 24.
Artículo en Inglés | MEDLINE | ID: mdl-35268632

RESUMEN

The study of animal mummification in ancient Egypt has recently received increasing attention from a number of modern scholars given the fact that this part of ancient Egyptian funerary and religious history is a practice yet to be fully understood. In this study, nine samples of embalming matter were extracted from six gazelle mummies from the archaeological site of Kom Mereh (modern village of Komir), dated to the Roman period of dominance in ancient Egypt. All samples were analyzed for the presence of inorganic and organic matter applying a multi-analytical approach based on Fourier transform infrared spectroscopy (FT-IR) and gas chromatography-mass spectrometry (GC-MS). Furthermore, in order to identify more specific compounds such as bitumen and beeswax in studied balms, each sample was subjected to a solid phase extraction (SPE) and saponification separation process, respectively. The results of this study revealed that the majority of the analyzed embalming substances sampled from six gazelle mummies from Kom Mereh were complex mixtures of plant oils, animal fats, conifer resin, and beeswax. In this regard, this study was able to report a practice until now unmentioned in the scientific literature, namely, the use of cruciferous oil, derived from seeds of Brassicaceae plants, in animal mummification.


Asunto(s)
Antílopes , Brassicaceae , Momias , Animales , Egipto , Antiguo Egipto , Embalsamiento/métodos , Historia Antigua , Aceites de Plantas , Semillas , Espectroscopía Infrarroja por Transformada de Fourier
3.
J Sep Sci ; 44(4): 850-859, 2021 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-33283962

RESUMEN

The aim of this paper is to establish a protocol by solid-phase extraction-gas chromatography-mass spectrometry leading to a wide and fine qualitative chemical characterization of the several natural substances present in human mummies' balms, using a minimal quantity of samples. In this study, nine samples were analyzed from mummies dating back from the Third Intermediate Period to the Roman Period, and were provided by the Confluences Museum (Lyon, France). Using solid-phase extraction, three fractions were examined in this protocol. The first one, eluted with hexane, concerned chemical families of hydrocarbons of bitumen. The second, eluted with ethanol, enabled terpenic compounds to be characterized and beeswax. The last one, composed of diethyl ether with 2% acetic acid, extracted carboxylic acids with a long aliphatic chain (fatty matter) and glycerides. This study also allowed the characterization of non-saponified compounds from beeswax to be obtained while excluding the common saponification step. The analyzed mummification balms were shown to contain fatty matter, beeswax, bitumen, and diterpenic resinous material. This one-pot solid-phase extraction-gas chromatography-mass spectrometry method was efficient in reducing both the number of analytical steps and the complexity of the archaeological balms subsequently analyzed by gas chromatography-mass spectrometry.


Asunto(s)
Resinas Compuestas/análisis , Grasas/análisis , Hidrocarburos/análisis , Momias , Extracción en Fase Sólida , Ceras/análisis , Egipto , Cromatografía de Gases y Espectrometría de Masas , Humanos
4.
Artículo en Inglés | MEDLINE | ID: mdl-29660677

RESUMEN

The characterization of ancient and modern alizarin-based lakes is a largely studied topic in the literature. Analytical data on contemporary alizarin-based lakes, however, are still poor, though of primary importance, since these lakes might be indeed present in contemporary and fake paintings as well as in retouchings. In this work we systematically investigate the chemical composition and the optical features of fifteen alizarin-based lakes, by a multi-analytical technique approach combining spectroscopic methods (i.e. Energy Dispersive X-ray Fluorescence Spectroscopy, EDXRF; Attenuated Total Reflectance Fourier-Transform Infrared Spectroscopy, ATR-FTIR; X-ray Powder Diffraction, XRD; UV induced fluorescence and reflectance spectroscopies) and chromatography (i.e. High-performance Liquid Chromatography coupled with a Photodiode Array Detector, HPLC-PDA). Most of the samples contain typical compounds from the natural roots of madder, as occurring in ancient and modern lakes, but in two samples (23600-Kremer-Pigmente and alizarin crimson-Zecchi) any anthraquinonic structures were identified, thus leading to hypothesize the presence of synthetic dyes. The detection of lucidin primeveroside and ruberythrique acid in some lakes suggest the use of Rubia tinctorum. One sample (23610-Kremer-Pigmente) presents alizarin as the sole compound, thereby revealing to be a synthetic dye. Moreover, gibbsite, alunite and kaolinite were found to be used as substrates and/or mordants. Visible absorption spectra of the anthraquinonic lakes show two main absorption bands at about 494-511nm and 537-564nm, along with a shoulder at about 473-479nm in presence of high amounts of purpurin. Finally, from the results obtained by UV induced fluorescence spectroscopy it is possible to figure out that, although it is commonly assumed that the madder lake presents an orange-pink fluorescence, the inorganic compounds, added to the recipe, could induce a quenching phenomenon or an inhibition of the fluorescence, as occurring in some commercial alizarin-based lakes.

5.
Environ Sci Pollut Res Int ; 24(36): 27746-27754, 2017 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-29098586

RESUMEN

The sandarac resin (Tetraclinis articulata) has been long used for its properties, mostly as a varnish component. Called juniper resin until the nineteenth century, the real botanical origin of sandarac is still unclear. The first approach to this issue is the review of the evolution of the etymology, terminology, and botanical description of sandarac through time. It seems that sandarac was mainly coming from T. articulata but the use of some juniper resins before the twentieth century is not to be excluded. The second approach is a chemical one; we used gas chromatography coupled to mass spectrometry to characterise the resin. As sandarac was the main component of the famous Italian varnish Vernice liquida, its characterisation is important for old paintings studies. However, although we could hope to differentiate sandarac, Juniperus communis and Juniperus oxycedrus resins by looking at their chemical composition, it appears that these resins are very similar. Besides, we notice a lack of old varnishes containing sandarac which complicates our work.


Asunto(s)
Cupressaceae/química , Pintura/análisis , Resinas de Plantas/análisis , Resinas de Plantas/química , Cromatografía de Gases y Espectrometría de Masas , Juniperus/química , Terminología como Asunto , Thuja/química
6.
Appl Spectrosc ; 71(12): 2616-2625, 2017 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-28730846

RESUMEN

Reflectance spectroscopy, ultraviolet (UV)-fluorescence spectroscopy, and multispectral imaging have been widely employed for pigment identification on paintings. From ancient times to the present, lead white, zinc white, and titanium white have been the most important white pigments used for paintings and they are used as pigment markers for dating a work of art. The spectral behavior of these pigments is reported in several scientific papers and websites, but those of their mixtures are quite unknown. We present a combined nondestructive approach for identifying mixtures of lead white, zinc white, and titanium white as powder and dispersed in two different binder media (egg yolk and linseed oil) by using reflectance spectroscopy, spectrofluorimetry, multispectral reflectance and UV-fluorescence imaging. We propose a novel approach for mapping the presence of white pigments in paintings by false color images obtained from multispectral reflectance and UV-fluorescence images. We found that the presence of lead white mixed with either zinc white or titanium white is highly detectable. Zinc white mixed with lead white or titanium white can be identified due to its UV-fluorescence emission, whereas titanium white in association with lead white or zinc white is distinguishable by its reflectance spectral features. In most cases, the UV-fluorescence analyses also permit the recognition of the binder media in which the pigments are dispersed.

7.
Phytochem Anal ; 20(6): 484-90, 2009.
Artículo en Inglés | MEDLINE | ID: mdl-19774541

RESUMEN

INTRODUCTION: Madder (Rubia tinctorum) has been used since ancient times as a source of pigments for dyeing and painting. Madder dyes are localised in roots and the native chemical population is composed of glycosiled and aglycone compounds. The aim of this study is to elaborate an efficient extraction process without any chemical denaturation of dyes. OBJECTIVE: To compare an optimised ultrasonic process, using for madder dye extraction, with two conventional procedures and to determine the efficiency of ultrasound on these vegetable matrix. METHODOLOGY: Madder roots were extract in a methanol-water mixture in 37 : 63 (v/v) for ultrasound and 80 : 20 (v/v) for reflux and agitation. HPLC-PAD analyses showed the anthraquinone proportion for each extraction process and their denaturing effects. Finally, cytohistological observations were made to show the consequence of each process on the cell organisation in madder roots. RESULTS: The results showed that the amount of extracted dyes was higher with UAE than with agitation and reflux. HPLC-PAD analysis revealed that the anthraquinone composition differed according to the extraction procedure. The UAE extracts presented an important richness in terms of anthraquinonic compounds that suggests a preserving effect. Cytohistological observations showed that the main alterations concerned the cell walls of phloem. After UAE the walls exhibited numerous pitted areas reflecting an ultrasound-induced cavitation that enhances the extraction effectiveness of this method. CONCLUSION: The study has shown the improvement of madder roots extraction both quantitatively and qualitatively using the efficiency of ultrasound-assisted extraction in comparison with magnetic agitation and reflux techniques.


Asunto(s)
Extractos Vegetales/farmacología , Raíces de Plantas/química , Rubia/química , Secuencia de Carbohidratos , Cromatografía Líquida de Alta Presión , Colorantes/química , Extractos Vegetales/química , Extractos Vegetales/aislamiento & purificación , Espectrofotometría Ultravioleta , Ultrasonido
8.
Ultrason Sonochem ; 16(1): 75-82, 2009 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-18617432

RESUMEN

An extraction method of madder (Rubia tinctorum) roots dyes is established and optimized to obtain the original chemical composition. A central composite design (CCD) was developed to specify the importance of the three major factors studied (time, temperature and solvent composition) affecting the ultrasound-assisted extraction of this matrix. A preliminary granulometric study of madder roots is realized in the aim to determine the optimal particles size corresponding to the best ultrasound effects. A comparison with the classical extraction method of madder dyes by reflux is described. The identification of the constituents of R. tinctorum is carried out by liquid chromatography coupled with a photodiode array detector (LC-PDA). Anthraquinonic aglycone and heterosidic dyes compounds are characterized by retention time and UV spectrum: alizarin (1,2-dihydroxyanthraquinone), purpurin (1,2,4-trihydroxyanthraquinone), lucidin (1,3-dihydroxy-2-hydroxymethylanthraquinone), rubiadin (1,3-dihydroxy-2-methylanthraquinone), xanthopurpurin (1,3-dihydroxyanthraquinone), pseudopurpurin (1,2,4-trihydroxy-3-carboxyanthraquinone), lucidin primeveroside, ruberythric acid (alizarin primeveroside), galiosin (pseudopurpurin primeveroside) and rubiadin primeveroside. The optimal experimental conditions are 18min, 36 degrees C and 37/63 MeOH/H(2)O (v/v).


Asunto(s)
Colorantes/aislamiento & purificación , Raíces de Plantas/química , Rubia/química , Ultrasonido , Cromatografía Líquida de Alta Presión , Costos y Análisis de Costo , Análisis Multivariante , Temperatura
9.
J Chromatogr A ; 1023(2): 277-85, 2004 Jan 16.
Artículo en Inglés | MEDLINE | ID: mdl-14753694

RESUMEN

A simple gas chromatography-mass spectrometry (GC-MS) method has been developed for the characterization of frankincense in archaeological samples. After trimethylsilylation of the methanolic extract, 15 triterpenoids have been found among the chemical constituents of commercial olibanum (alpha-boswellic acid, 3-O-acetyl-alpha-boswellic acid, beta-boswellic acid, 3-O-acetyl-beta-boswellic acid, alpha-amyrin, beta-amyrin, lupeol, 3-epi-beta-amyrin, 3-epi-beta-amyrin, 3-epi-lupeol, alpha-amyrenone, beta-amyrenone, lupenone, 3alpha-hydroxy-lup-20(29)-en-24-oic acid and 3-O-acetyl-hydroxy-lup-20(29)-en-24-oic acid). These compounds have been unequivocally identified by retention time and mass spectral comparison with pure standards previously isolated, for the most part, in our laboratory. Within these triterpenes, acid ones, the corresponding O-acetates, and their products of degradation were found to be characteristic of frankincense (Boswellia resin). The presence of these unusual triterpenic compounds in an archaeological resinous sample, recovered during excavations from Dahshour site (Egypt, XIIth Dynasty), enabled us to identify unambiguously frankincense resin among several other materials. Additional chromatographic peaks of this sample were assigned to broad chemical classes using retention time and mass spectra features.


Asunto(s)
Boswellia/química , Cromatografía de Gases y Espectrometría de Masas/métodos , Estándares de Referencia
10.
Phytochemistry ; 62(4): 537-41, 2003 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-12560022

RESUMEN

A new lupane-type triterpene, 3alpha-hydroxy-lup-20(29)-en-24-oic acid, was isolated from the methanolic extract of "Erytrean-type" resin of commercial frankincense together with the known 3alpha-hydroxy-olean-12-en-24-oic acid (alpha-boswellic acid) and 3alpha-hydroxy-urs-12-en-24-oic acid (beta-boswellic acid). Their structures were characterized on the basis of chemical and spectral evidence including two dimensional NMR experiments and mass spectrometric techniques.


Asunto(s)
Boswellia/química , Triterpenos/aislamiento & purificación , Acetilación , Cromatografía en Gel , Cromatografía Líquida de Alta Presión , Espectroscopía de Resonancia Magnética , Metilación , Estructura Molecular , Resinas de Plantas/química , Estereoisomerismo , Triterpenos/química
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