Francesca Romana Gallo

Chemical fingerprinting of Equisetum arvense L. using HPTLC densitometry and HPLC

Equisetum arvense L. is a herbaceous medicinal plant, commonly known as horsetail, whose extracts have been reported to possess diuretic and haemostatic properties. The aim of this study was to evaluate the use of fingerprint chromatographic methods on commercially available raw materials or preparations of E. arvense L. in order to ascertain their quality and identify possible adulterants using HPLC and HPTLC densitometry. Two chromatographic methods were used to determine the chemical fingerprints of E. arvense and other allied species. The first was based on HPTLC identification followed by densitometric measurement at 350 nm. The second was based on HPLC separation. The ease of sample preparation and the possibility of simultaneous analysis of several samples in a short time make HPTLC a method of choice for the comprehensive quality evaluation of herbal products.

The Modern Analytical Determination of Botanicals and Similar Novel Natural Products by the HPTLC Fingerprint Approach

Abstract Efficient, useful and sensitive analytical devices for the quality control of complex mixtures of natural products are urgently needed. Controls should be based on simple, viable, comprehensible and low cost methods. High Performance Thin Layer Chromatography (HPTLC) the last evolution of planar chromatography, is a reliable candidate for analysis of botanicals. Although HPLC remains the best choice for organic substances, HPTLC can solve several problems in a quicker, simpler and easier method. Furthermore, the visualization and the analysis of similar products performed exactly in the same conditions, allow an evident, good and safe result of comparison. The paper is dedicated to HPTLC application on selected market products, in order to evidence benefits and limits of the HPTLC fingerprint approach.

Traceability in Multi-Ingredient Botanicals by HPTLC Fingerprint Approach

A high-performance thin-layer chromatography (HPTLC) method was developed for simple and rapid chemical analyses of multi-ingredient botanicals. The method was based on comparison of the fingerprint of the marketed multi-ingredient botanical with the fingerprints of the extracts of its component plants and of a handmade mixture of the constituent extracts in a ratio as similar as possible to that of the market product, when labeled. Planar chromatography analysis was completed by a densitometric scansion. The analyses revealed a good correspondence between the market products and the handmade mixture of standard extracts.

Plants and parts of plants used in food supplements: an approach to their safety assessment

In Italy most herbal products are sold as food supplements and are subject only to food law. A list of about 1200 plants authorised for use in food supplements has been compiled by the Italian Ministry of Health. In order to review and possibly improve the Ministrys list an ad hoc working group of Istituto Superiore di Sanità was requested to provide a technical and scientific opinion on plant safety. The listed plants were evaluated on the basis of their use in food, therapeutic activity, human toxicity and in no-alimentary fields. Toxicity was also assessed and plant limitations to use in food supplements were defined.

Alkaloids from Glaucium flavum from Sardinia

Glaucium flavum collected in Sardinia was studied using a phytochemical approach in order to evaluate its alkaloid composition and obtain a comparison with the alkaloid contents of the same species in populations of other geographic proveniences. In fact, different chemoecotypes of G. flavum have been identified, on the basis of their particular content and composition in alkaloids, in accordance with the different distribution areas. The analysis showed that Sardinian G. flavum contains a homogeneous alkaloid pattern of aporphyne type, significantly different from those reported for populations from other parts of Europe.

Bearberry identification by a multidisciplinary study on commercial raw materials.

Herbal species different from the official bearberry, Arctostaphylos uva-ursi, are sold through conventional markets and also through non-controlled Internet websites, putting consumer safety at risk owing to the lack of quality control. Recently, Arctostaphylos pungens has become one of the most used species as a raw material for herbal medicines and dietary supplements in the place of official bearberry, a plant used for the treatment of various urinary disorders. A fingerprint identification based on an integrated application of different analytical techniques (HPTLC, NMR, HPLC-DAD and LC-ESI-MS) is here described to distinguish A. uva-ursi from A. pungens. The HPTLC and HPLC-DAD fingerprints resulted the simplest methods to differentiate the two species, whereas LC-ESI-MS was more useful to quantify arbutin, the main component of bearberry, and to evaluate its different content in the two species. This multidisciplinary study showed for the first time a specific phytochemical fingerprint of the new species A. pungens.

Voacamine Modulates the Sensitivity to Doxorubicin of Resistant Osteosarcoma and Melanoma Cells and Does Not Induce Toxicity in Normal Fibroblasts

In previous studies it has been demonstrated that the plant alkaloid voacamine (1), used at noncytotoxic concentrations, enhanced the cytotoxicity of doxorubicin and exerted a chemosensitizing effect on cultured multidrug-resistant (MDR) U-2 OS-DX osteosarcoma cells. The in vitro investigations reported herein gave the following results: (i) the chemosensitizing effect of 1, in terms of drug accumulation and cell survival, was confirmed using SAOS-2-DX cells, another MDR osteosarcoma cell line; (ii) compound 1 enhanced the cytotoxic effect of doxorubicin also on the melanoma cell line Me30966, intrinsically drug resistant and P-glycoprotein-negative; (iii) at the concentrations used to sensitize tumor cells, 1 was not cytotoxic to normal cells (human fibroblasts). These findings suggest possible applications of voacamine (1) in integrative oncologic therapies against resistant tumors.

Polyketides from Eleutherine bulbosa

Four new polyketides, (R)-4-hydroxyeleutherin, eleuthone, eleutherinol-8-O-β-D-glucoside and isoeleuthoside C (dihydroisoeleutherin-5-O-β-D-gentiobioside) were isolated from the bulbs of Eleutherine bulbosa, to join eleutherin, isoeleutherin, eleutherinol, eleutherol, eleuthoside B (eleutherol-4-O-β-D-gentiobioside), eleuthoside C (dihydroeleutherin-5-O-β-D-gentiobioside), hongconin (4-oxodihydroisoeleutherin) and elecanacin, which have already been isolated from the same plant. The structures of the new polyketides, based on oxydated cyclic systems, have been elucidated by chemical and spectroscopic methods.

7-Epimer oxindole alkaloids of Cabucala cryptophlebia: their 13C-NMR and CD data

The isolation, (13)C-NMR and CD data of two 7-epimer oxindole alkaloids, 10,11-dimethoxyisomitraphylline (1) and 10,11-dimethoxymitraphylline (2) from Cabucala cryptophlebia are reported.

Analysis of FCE 23762 (methoxymorpholinodoxorubicin hydrochloride), a new antitumour agent, by HPTLC and scanning densitometry

A simple, rapid and reproducible high-performance thin-layer chromatographic (HPTLC) method using UV or fluorescence scanning densitometry has been developed for the assay and purity control of methoxymorpholinodoxorubicin hydrochloride (FCE 23762). With a mobile phase of chloroform-methanol-acetic acid (93:6:1, v/v/v) and a silica gel plate, all potential impurities were separated from the main component and from each other. Detection limits at a signal-to-noise ratio of 2:1 were a few nanograms for UV detection and < 1 ng for fluorescence emission. The RSD values for the examined compounds were all < 3%.