Characterisation of saponins from Hedera nepalensis in Vietnam northwest mountainous areas with the aid of high-resolution mass spectrometry.

This research aims to explore the saponins composition of H. nepalensis in four northwest mountainous areas of Vietnam including Ha Giang, Lai Chau, Lao Cai, and Lang Son with the aid of high-resolution mass spectrometry. As a result, 42 saponins are successfully identified in H. nepalensis leaves by UHPLC-Q-TOF-MS/MS analyses, in which two 30-noroleanane and four oleanane triterpene saponins structures have been reported for the first time. Two structures of compound 20 were discovered in four samples. Two structures of compound 8 were found in H. nepalensis from Ha Giang and Lao Cai, while two structures of compound 28 were not observed in Lang Son. Different environmental and climatic circumstances in various places may have an impact on chemical constituents of H. nepalensis. By providing the phytochemicals profile of H. nepalensis leaves, our study supports the orientation for future research on this medicinal plant as well as other Hedera species.

Chemical Composition, Antimicrobial, Nitric Oxide Inhibition and Cytotoxic Activity of Essential Oils from Zanthoxylum acanthopodium DC. Leaves and Stems from Vietnam.

This study was aimed to investigate the chemical composition and biological activities of leaf and stem essential oils of Zanthoxylum acanthopodium DC. from Vietnam. Their chemical composition was analyzed by GC/MS. Antimicrobial activities were evaluated by microdilution broth assay. Anti-inflammatory activity was evaluated by the ability to inhibit nitric oxide production in macrophage cells. Cytotoxic activity was evaluated using the sulforhodamine B assay on three human cancer cell lines. Forty-four compounds were identified in the leaf oil, among which dehydroaromadendrane (23.4 %), (E)-carpacin (17.6 %), 2-tridecanone (12.2 %), and 9-methyl-2-decanone (11.8 %) were the most abundant. The stem oil contained fifty-five identified constituents, mainly γ-gurjunene (51.1 %) and butyl acetate (11.8 %). Both oils exhibited inhibitory effects on three bacterial strains, namely S. aureus, E. coli, P. aeruginosa and a fungal strain C. albican, while showed insignificant effects on B. subtilis, L. fermentum, and S. enterica. Both oils showed weak NO production inhibition in LPS-induced RAW264.7 cells, but exhibited potent cytotoxic activity against all three tested cell lines SK-LU-1, MCF-7, and HepG2 with the IC50 values ranging from 16.03±0.77 to 35.60±1.62 µg/mL. This is the first report on the antimicrobial, anti-inflammatory and cytotoxic activities of essential oils from the leaves and stems of Z. acanthopodium.

Investigation on the in vitro antioxidant capacity of methanol extract, fractions and flavones from Oroxylum indicum Linn bark

ABSTRACT Antioxidants from natural sources hold high values regarding their indispensible roles in the development of nutraceuticals, pharmaceuticals and cosmetic products. Oroxylum indicum L. is a common medicinal plant with a wide range of therapeutic properties, including a notable antioxidant potency that was reported, yet has not been subjected to more detailed studies. The present study evaluated the potency of Oroxylum indicum methanol stem bark extract, along with its hexane, ethyl acetate, methanol fractions, three flavones including baicalein, oroxylin A and chrysin using DPPH assay. In terms of IC50 values, the crude extract (65,48 µg/mL) exhibited moderate inhibitory activity which was as half potent as that of its ethyl acetate fraction (32,94 µg/mL). This fraction was also superior to the methanol and hexane fractions, as their IC50 were 57,19 and 137,95 µg/mL respectively. Remarkably, a yellow powdery sub-fraction consisted of isolated compounds showed powerful activity (32,89 µg/mL) compared to those of its components, revealing the intriguing effect of synergism while giving evidence for the theory of structure-activity relationship between some flavones and their antioxidant capability. Perpetual search for new radical scavenging agents in Oroxylum indicum is emboldened considering its partially exploited potential in this study

Low-molecular-weight compounds with anticoagulant activity from the scorpion Heterometrus laoticus venom.

Low-molecular-weight compounds with anticoagulant activity were isolated from the scorpion Heterometrus laoticus venom. The determination of the structure of the isolated compounds by nuclear magnetic resonance and mass spectrometry showed that one of the isolated compounds is adenosine, and the other two are dipeptides leucyl-tryptophan and isoleucyl-tryptophan. The anticoagulant properties of adenosine, which is an inhibitor of platelet aggregation, is well known, but its presence in scorpion venom is shown for the first time. The ability of leucyl-tryptophan and isoleucyl-tryptophan to slow down blood clotting and their presence in scorpion venom are also established for the first time.