Antimicrobial activity of flavonoids glycosides and pyrrolizidine
alkaloids from propolis of Scaptotrigona aff. postica.
Abstract
Stingless bees belonging to the Meliponinae subfamily, are known as
meliponines. Scaptotrigona affinis postica Latreille, 1807 from
northeast of Brazil is popularly known as ‘tubi’ in Maranhão State.
Scaptotrigona, which is widely distributed in neotropical regions,
includes species that build their hives in pre-existing cavities.
Flavones di-C-glycosides, and the pyrrolizidine alkaloid 7-(3-methoxy-2-
methylbutyryl)-9-echimidinylretronecine were reported previously in
propolis from S. postica. Fractions 40 AEP and 40 MEP from ethanolic
extract were analyzed by LC-MS. The chromatographic profile of fractions
40 AEP and 40 MEP revealed the presence of many pyrrolizidine alkaloids,
among them, lithosenine (14), lithosenine arabinoside (19),
7-angeloyl-9-(2,3- dihydroxybutyryl) retronecine (1),
7-(2-methylbutyryl) retronecine (3), 9-sarracinoylretronecine (13) and
viridinatine (8), besides the flavonoids schaftoside (15),
aromadendrin-7-O-methyl ether (12),
7-methoxy-5,6,3’,4’,5’,6’-hexahydroxy-flavone-3-O-glucuronide (11),
mangiferin (10) and 3-O-methyl mangiferin (17). Fractions 40 AEP and 40
MEP showed antimicrobial activity against Gram negative bacteria,
including Escherichia coli D31- streptomycin resistant. Cell viability
was expressed in terms of the relative absorbance of treated and
untreated cells (control). There was no statistical difference between
treated and untreated cells.