Implementation of a MS/MS database for isoquinoline alkaloids and other annonaceous metabolites.

This data descriptor reports on the upload to a public repository (GNPS) of the IQAMDB, IsoQuinoline and Annonaceous Metabolites Data Base, comprising 320 tandem mass spectra. This project originated from our in-house collection of isoquinolines. The diversity of compounds included in this database was further extended through the contribution of two additional laboratories involved in isoquinoline alkaloids research: University of Angers and University of Manaus. The generated MS/MS data were processed and annotated on an individual basis to promote their straightforward reuse by natural product chemists interested in either the description of new isoquinoline alkaloids or the dereplication of isoquinoline-containing samples. The interest of the current repertoire for dereplication purposes has been validated based on the molecular networking of the well-investigated plant model Annona montana against the IQAMDB-implemented GNPS.

Composition, and antimicrobial and remarkable antiprotozoal activities of the essential oil of rhizomes of Aframomum sceptrum K. Schum. (Zingiberaceae).

The essential oil from the rhizomes of Aframomum sceptrum (Zingiberaceae) was analyzed by GC/MS, and its major constituents were found to be ß-pinene (12.7%), caryophyllene oxide (10.0%), and cyperene (6.0%). The oil was also evaluated for antimicrobial activities, in comparison with ß-pinene, caryophyllene oxide, and the leaf essential oil of Melaleuca alternifolia (Myrtaceae). The A. sceptrum essential oil exhibited bacteriostatic activity against the Gram-positive bacteria Bacillus subtilis, Staphylococcus epidermidis, and S. aureus, but not against Gram-negative bacteria. Moreover, it showed mild fungicidal activity against Candida albicans and Aspergillus fumigates, and remarkable antiprotozoal activity against Trypanosoma brucei brucei (MLC of 1.51 µl/ml) and Trichomonas vaginalis (IC(50) of 0.12±0.02 and MLC of 1.72 µl/ml).

Apoprunellelactone (APL), an antiprotozoal lactone from the stem barks of Isolona cooperi Hutch. & Dalziel (Annonaceae).

Bioassay guided fractionation of the stem barks of Isolona cooperi led to the isolation of a new lactone, apoprunellelactone (APL, 1), and two known compounds, 5-[1-hydroxyhexyl]-2H-furan-2-one (2) and oleic acid (3). Their structures were elucidated by spectral analysis including MS, UV, IR, 1D and 2D-NMR spectroscopy. Evaluated for its antiprotozoal activities, APL (1) was found to be the most active on Leishmania donovani and L. major promastigotes with EC50 values of 16.3 and 8.2 µM, respectively. Against Trypanosoma brucei brucei trypomastigote forms, the activity of APL was moderated (MEC = 38.0 µM). Its hemisynthetic ester acetic derivative (1c) was 2-42 times more active than that of the APL and reference drugs, justifying further in vivo evaluation of the two compounds (1 and 1c) on Leishmania sp and Trypanosoma brucei brucei/mice models.

Bioactive phloroglucinols from Mallotus oppositifolius.

The two new acylphloroglucinol derivatives, methylene-bis-aspidinol AB (1) and mallopposinol (2), together with the nine known compounds, aspidinol B (3), methylene-bis-aspidinol (4), (+)-α-tocopherol (5), lupeol (6), stigmasterol (7), phytol (8), bergenin (9), squalene (11) and methyl gallate (10) were isolated from the leaves of Mallotus oppositifolius. Their structures were elucidated by spectral analysis including MS, 1D and 2D-NMR spectroscopy. In vitro trypanocidal and antileishmanial activities of compounds 1-9 were evaluated. Mallopposinol (2) and aspidinol B (3) displayed weak antileishmanial activities against Leishmania donovani promastigotes, with EC50 values of 21.3 and 38.8µM, respectively. Only the methylene-bis-aspidinol (4) exhibited trypanocidal activity against Trypanosoma brucei brucei trypomastigotes (LC100=0.8µM) similar to the reference drug pentamidine (LC100=0.4µM).