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Abstract: Propolis of Australian stingless bees (Tetragonula carbonaria, Meliponini) originating from Corymbia torelliana (Myrtaceae) fruit resins was tested for its antimicrobial activities as well as its flavonoid contents. This study aimed at the isolation, structural elucidation and antibacterial testing of flavanones of C. torelliana fruit resins that are incorporated into stingless bee propolis. Flavanones of this study were elucidated by spectroscopic and spectrometric methods including UV, 1D and 2D NMR, EI-MS, ESI-MS and HR-MS. The results indicated known C-methylated flavanones namely, 1 (2S)-cryptostrobin, its regioisomer 2 (2S)- stroboponin, 3 (2S)- cryptostrobin 7-methyl ether, and 6 (2S)- desmethoxymatteucinol, and known flavanones 4 (2S)- pinostrobin and 5 (2S)- pinocembrin as markers for C. torelliana fruit resins and one propolis type. Ethanolic preparations of propolis were shown to be active against Staphylococcus aureus (ATCC 25923) and to a lesser extent against Pseudomonas aeruginosa (ATCC 27853). C. torelliana flavanones inhibited the growth of S. aureus therefore contributing to the antibacterial effects observed for Australian stingless bee propolis extracts. [Copyright &y& Elsevier]

Information about the annual American Society of Mass Spectrometry meeting held in Minneapolis, Minnesota on June 9 to 13, 2013 is presented. Topics include the embryonic playground of editorial creativity. The meeting featured several representatives of the Associate Editorial Board including David Kilgour of Great Britain, Adam Trevitt of Australia and Sarah Trimpin of the U.S.

The article reports on the application of the derivatization technique in High Performance Liquid Chromatography and Capillary Electrochromatography for the development of the Matrix-Assisted Laser Desorption-Ionization-Mass Spectrometry, by Andreas Rizzi and colleagues at the University of Vienna, in Australia. Rizzi and colleagues have derivatized the glycopeptides with the 6-aminoquinolyl-N-hydroxysuccinimidyl carbamate to examine glycopeptides formation. They found that small peptides and glycopeptides can be easily detected when derivatization was used. However, only glycopeptides with large peptide backbones were identified when derivatization was not present.