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Jayarao, B. M., Gillespie, B. E. and Oliver, S. P. (1998): Application of randomly amplified polymorphic DNA fingerprinting for species identification of bacteria isolated from bovine milk. Journal of Food

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Abstract  

The multi-elemental content of sixteen glass beads and eight glass samples from archeological site Sg Mas in Bujang Valley (finding from 5 th to 14 th century) were assayed by neutron activation analysis (NAA). Ten beads differed in colour and eight of them were opaque. Contents of twentyfour elements, which might be present in the samples as a flux, stabilizer, colorants or opacifier were examined. The elements Al, Br, Cl, Co, Cr, Fe, Hf, K, Mn, Na, Sc,Th, Zn and Zr were detectable in all samples. On the other hand, concentration of the elements As, Ba, Ca, Cs, Rb, Sb, Ta, Ti, U, and V were below the detection limit in some samples. The concentration of elements found are discussed in terms of color and/or opacity of the glass bead and glass samples. Although the elemental composition does not fully explain the color and opacity of the studied materials, it can still be used as fingerprint of the glass used for the bead making.

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Abstract  

The TG, DTG and DSC methods were used for investigation of the thermo-oxidative degradation in static air atmosphere and oxygen flow of some sorts of lime tree wood (recent lime tree woods with different preparations, old lime tree woods extracted from some Romanian historical and/or cultural objects). At the progressive heating in the mentioned atmospheres, all the investigated materials exhibit three successive processes, associated with dehydration and two complex thermo-oxidative processes. Each analyzed material has a characteristic thermogram (TG, DTG and/or DSC curve) that can be considered a material “fingerprint”. It was pointed out that the following non-isothermal parameters can be used for distinction between a new and old lime tree wood: mass loss in the first process of thermo-oxidation, ratio between the mass losses in the first and the second processes of thermo-oxidation, the maximum rate of the first process of thermo-oxidation. Consequently, the certification of a patrimonial object manufactured from lime tree wood could be performed by applying the thermal analysis methods.

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This study was designed to develop a simple, sensitive, selective, and precise high-performance thin-layer chromatography (HPTLC) fingerprint and quantitative estimation method for the analysis of three phenolic compounds from nine Leucas species. The developed HPTLC method was validated according to the International Conference on Harmonization guidelines. The method permits reliable quantification of one important phenolic acid (gallic acid) and two hydroxycinnamic acids (caffeic and ferulic acids) in 50% hydroethanolic extracts on silica gel with toluene—ethyl acetate—formic acid 8:2:1 (v/v) as the mobile phase. The system showed good resolution and separation of caffeic, ferulic, and gallic acids (at R f values 0.48, 0.60, and 0.30, respectively) from the other constituents of the extract. Densitometric scanning was done at 300 nm in absorbance mode. All the results obtained by the developed method were statistically compared for validation parameters, for accuracy and good precision. Caffeic, ferulic, and gallic acids were estimated in all the aforesaid nine Leucas species, but the quantity varied from species to species. Further, these phenolics were reported from the aforesaid Leucas species for the first time, except for Leucas lanata and Leucas urticifolia. However, Leucas biflora, Leucas decemdentata, and Leucas stricta were documented for their chemical constituents for the first time. The proposed HPTLC method can be used for routine quality testing of Leucas species.

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A simple, rapid, and precise high-performance thin-layer chromatographic method has been established for quantitative analysis of myricetin in the stem bark of Myrica esculenta, family Myricaceae. The marker myricetin was separated from other components of stem bark extract on silica gel 60 F254 HPTLC plates with toluene-ethyl acetate-formic acid-methanol 3:3:0.6:0.4 (v/v) as mobile phase. Densitometry in absorbance-reflection mode at 268 nm was used for quantitative analysis of myricetin. The stem bark of M. esculenta was found to contain 0.225% (w/w) myricetin. The method was validated for linearity, accuracy, precision, and specificity in accordance with ICH guidelines. The calibration plot was linear between 0.4 and 2.0 μg per band for myricetin. The limits of detection and quantitation were 0.0939 and 0.2845 μg per band, respectively. The method can be used as a quality control-method for fingerprint profiling and quantitative analysis of the stem bark of Myrica esculenta.

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To evaluate the quality of Fructus Arctii, an accurate and reliable method of high-performance liquid chromatography/diode array detection—electrospray ionization—mass spectrometry (HPLC/DAD—ESI—MS) was developed. Nine compounds, including chlorogenic acid, caffeic acid, trans-p-hydroxycinnamic acid, arctiin, arctignan A, ethyl caffeate, matairesinol, arctigenin, and lappaol B, were determined simultaneously in 19 batches of Fructus Arctii samples collected from different localities. Nineteen common peaks were identified or tentatively assigned by comparing their mass spectrometric data with reference compounds, self-established compound library, and published literatures. Also, the 19 common peaks were selected as characteristic peaks to assess the similarity of chromatographic fingerprinting of these samples. Moreover, hierarchical clustering analysis (HCA) and principal components analysis (PCA) were successfully applied to demonstrate the variability of samples. The results indicated the content of nine compounds that varied greatly among the samples, and 19 samples collected from different localities could be discriminated. Furthermore, chlorogenic acid, arctiin, and arctigenin were found to be chemical markers for evaluating the quality of Fructus Arctii.

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Plumbago zeylanica L. (PZ) is a significant medicinal plant in Ayurveda, so is used for the treatment of various disorders. The main active part of this plant is the root, and due to its inherent uses, it has been exploited hence becoming an endangered species. Dyerophytum indicum (Gibbs ex Wight) Kuntze (DI), mainly considered as a substitute of PZ, is also an important folklore medicine, used in many health problems. Both plants are much similar in their physical as well as chemical properties. However, an effective validation is required before declaration of substitution. In the present study, quantitative and qualitative estimations were performed on both plants with the help of modern analytical techniques. Simultaneous high-performance liquid chromatography (HPLC) and high-performance thin-layer chromatography (HPTLC) and quantitative determinations of β-sitosterol have been performed for comparing both plants, i.e., PZ and DI. HPTLC fingerprinting analysis was also performed comparatively in different plant parts of PZ and DI. Successive extracts from different plant parts were evaluated for TLC separation profile of secondary metabolites. A comparative polyphenolic content- and antioxidant screening was evaluated to check the free radical scavenging effect of both plants (leaf, stem, and root) in comparison with the standards gallic and ascorbic acid.

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Summary

A simple and rapid method, using online ultraperformance liquid chromatography with photodiode array detection and electrospray ionization mass spectrometry (UPLC-PDA-eλ-ESI-MS/MS), was developed for the in-depth analysis of 50 batches Radix et Rhizoma Rhei. The analysis was performed on a UPLC BEH C18 column using a gradient elution system. Baseline separation could be achieved in less than 7.5 min. At the same time, on the basis of the 50 batches of samples collected from representative cultivated regions, a novel chromatographic fingerprint was devised by UPLC-PDA, in which 27 common peaks were detected and identified by the developed UPLC-MS/MS method step by step according to fragmentation mechanisms, MS/MS data, standards, and relevant literature. Many active components gave prominent [M - H] ions in the ESI mass spectra. These components include anthraquinones, sennosides, stilbenes, glucose gallates, naphthalenes, and catechins. Furthermore, based on the information of these Radix et Rhizoma Rhei components, and further combined with discriminant analysis, a novel discriminant analysis equation (DAE) was established for the quality control of Radix et Rhizoma Rhei for the first time.

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Abstract  

The thermal analysis methods (TG, DTG and DTA) were used for the investigation of the thermal degradation of some recent manufactured tanned leathers, leathers that are supports of cultural or historical objects (leather from book covers (XVII-XIX centuries); leather from an Austrian belt (Franz Joseph period), Cordoba leather (XVII century), lining leathers), recent and patrimonial parchments and recent extracted collagen (sorts of collagen obtained from bovine leather at different pH-values, bovine collagen with different hydration degree). At progressive heating, all investigated materials exhibit two main successive processes, associated with the dehydration and thermo-oxidative degradation. Each analyzed material has a characteristic thermal analysis curve (TG, DTG and DTA) that can be considered a material 'fingerprint'. This result suggests the use of the thermal analysis methods to identify of leathers from which the patrimonial objects are manufactured. The rate of thermo-oxidation of recent manufactured tanned leathers is substantially higher than the rate of the same process corresponding to naturally aged leathers that exhibit values of the thermo-oxidation rate appropriate to those obtained for parchments and collagens. The rate of thermo-oxidation of leather can thus be used as a criterion to distinguish between recent manufactured leather and patrimonial one.

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A rapid and reliable HPTLC method for analysis of aristolochic acids (AA) has been developed on the basis of a TLC procedure previously published by the German Drug Codex (DAC). The new method enables visual detection of the acids with certainty at very low levels (400 pg absolute of aristolochic acid A) in plant material and can therefore be used for screening Chinese drugs to ensure their safety on the basis of the absence of AA. Qualitatively Stephania tetrandra can be distinguished from various Aristolochia spp., Asarum spp. , and other drugs with similar Chinese names, on the basis of fingerprints.At least five different aristolochic acids can be detected in Aristolochia spp. The method is very specific and sensitive and is suitable for establishing and documenting adulteration of Stephania raw material with less than 1% Aristolochia fangji . By use of scanning densitometry quantitative determination of AA can be performed at low concentrations (1 ppm). Validation data (ICH) including linearity, limit of detection, precision, and accuracy are presented. The performance of the method is discussed on the basis of comparison with an HPLC-MS method proposed by the US FDA. HPTLC analysis is presented as a very useful complementary technique to the more sophisticated procedures used in legal cases.

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