Structural characterization of three cytotoxic steroidal saponins from the leaves of Agave desmetiana hort.

Three steroidal saponins detected by LC-MS were isolated from the leaves of Agave desmetiana hort. The three saponins were characterized as; Tigogenin 3 - [{O - ß - D - xylopyranosyl (1 â†’ 2) - α - L-rhamnopyranosyl (1 â†’ 3)}-ß-D- glucopyranoside), Tigogenin- 3 - ([O- α -L-rhamnopyranosyl (1 â†’ 3) - ß - D - glalactopyranosyl (1 â†’ 2)] - ß - D - glucopyranoside) and Tigogenin- 3 - ([{O - α - L - rhamnopyranosyl (1 â†’ 4)} - ß - D - galactopyranosyl (1 â†’ 3) - ß - D - xylopyranosyl (1 â†’ 2)] - ß - D - glucopyranoside). Identification and structure elucidation of the isolates were done via 1D and 2D NMR techniques, and chemical methods. Cytotoxic activity for the crude saponins and the three isolated compounds were evaluated against Hepg-2 and Mcf-7 cell lines. Compound 2 proved to be the most cytotoxic against tested cell lines with an IC50 2.97 and 2.49 µg/ml respectively.

The anti-inflammatory, anti-ulcer activities and phytochemical investigation of Cucumis melo L. cv. Ismailawi fruits.

This study aims to evaluate the anti-inflammatory and anti-ulcer activities of Cucumis melo L. cv. Ismailawi fruits, as well as the investigation of the phenolic content and lipoidal matter composition via high performance liquid chromatography and gas chromatography coupled to mass spectrometry respectively. Both the petroleum ether and defatted methanol extracts of the fruit pulp showed 63.13% and 54.97% decrease in oedema volume respectively after 4 h in comparison to indomethacin standard drug. Both the petroleum ether extract and ethyl acetate fractions at a dose (200 mg/kg) showed significant anti-ulcer activity decreasing both ulcer number and severity in comparison to ranitidine as standard drug. Histopathological investigation further confirmed these results. Moreover; this is the first report for the investigation of the phenolic content and the lipoidal matter of Cucumis melo L. cv. Ismailawi fruits where methyl palmatate, gallic acid and rutin represented the major detected components.

LC-ESI-MS/MS profiling of alkaloids and antiproliferative activity of Pachypoduim lamerei drake leaves.

In the present study, evaluation of the antiproliferative activity of Pachypodium lamerei Drake leaves (family Apocyaceae) against human breast cancer cell lines MDA-MB-231 was done for the total methanolic extract, crude alkaloidal mixture and ursolic acid using the MTT colorimetric assay. The methanolic extract showed the strongest antiproliferative activity followed by ursolic acid and crude alkaloidal fraction with an IC50 equal to 6.2, 14.55 and 56.3 µg/ml respectively compared to oleocanthal. It is the first record for the LC/ESI-MS/MS alkaloidal profiling of the leaves of P. lamerei. Seven alkaloids were tentatively identified according to their fragmentation patterns. Four alkaloids were related to the parent indole class and two alkaloids belong to the quinoline class in addition to one steroidal alkaloid with a pregnan nucleus. Phytochemical investigation of the methanolic extract led to the isolation of three triterpenoidal compounds including ursolic acid, 11,12-didehydroursolic acid lactone and ursolic acid lactone.

LC/ESI-MS/MS profiling of Ulmus parvifolia extracts and evaluation of its anti-inflammatory, cytotoxic, and antioxidant activities.

In this study, a comparative liquid chromatography/mass spectroscopy (LC/ESI-MS/MS) profiling of different fractions of Ulmus parvifolia leaves and stems was performed. Identification of compounds was based on comparing the mass spectrometric information obtained including m/z values and individual compound fragmentation pattern to tandem mass spectral library search and literature data. Eleven compounds were tentatively identified in the different analyzed fractions. One of the major constituents of this plant was isolated and identified as Icariside E4 [dihydro-dehydro-diconiferyl alcohol-4-O-α-L-rhamnopyranoside] (5). The evaluation of anti-inflammatory activity of the total methanolic extract using nitric oxide inhibition on LPS-stimulated RAW 264.7 cells model strong anti-inflammatory activity with 17.5% inhibition of nitric oxide production versus 10% inhibition for dexamethasone. The cytotoxic activity of the methanolic extract and Icariside E4 was evaluated against four types of human cell lines using MTT assay. Icariside E4 showed cytotoxic effect against Hep-G2, MCF-7, and CACO-2 cell lines compared to a negligible activity for the total extract. The same extract showed a moderate antioxidant activity with SC50=362.5 µg/mL.