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Looking for a biotechnical potential, aqueous extracts of leaves of 12 native species used in the Mayan traditional medicine of the coastal dune and mangrove of Yucatan (Mexico) were selected to evaluate their biological activities. Rhizophora mangle and Manilkara zapota showed the highest free radical scavenging activity (3.94 ± 0.19 and 6.42 ± 0.32 μg/mL, respectively), and the highest antihypertensive activity was obtained from Solanum donianum (0.38 μg/mL). The anti-hyperglycemic activity of these species was also tested; the highest activities were registered with R . mangle . The antimicrobial activity of Malvaviscus arboreus , S . donianum , M . zapota , and R . mangle at 10% (w/v) was positive against six human pathogenic bacteria and Bonellia macrocarpa against one pathogenic fungus. Solanum donianum , M . zapota , B . macrocarpa , and R . mangle were positive against two pathogenic plant fungi. These results show that the aqueous extracts of five native plants of the Yucatan coast have potential as antioxidants, ACE inhibitors, α-amylase and α-glucosidase inhibitors, and as antimicrobials, which make their exploration for utilization in the agricultural and pharmaceutical industries a possibility.

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Aims To analyse the non‐glycosylated protein fraction from Melipona beecheii honey for antimicrobial activity against Escherichia coli O157:H7. Methods and Results The proteins from M. beecheii honey were separated according to their degree of glycosylation using Concanavalin A‐affinity chromatography. The total protein extract and its fractions were analysed by 1D and 2D electrophoresis. We also determined the antimicrobial and antihaemolytic activities of the total protein extract and the non‐glycosylated fraction. Furthermore, we evaluated the effect of this non‐glycosylated fraction for the expression of the Stx1, Stx2, EAE and HlyA pathogen genes. Melipona beecheii honey contained at least 24 proteins with molecular weights ranging between 7·6 and 95 kDa and isoelectric points between 3 and 10, three proteins from the 24 are non‐glycosylated. The non‐glycosylated fraction had an MIC90 of 1·128 µg ml−1, and this fraction inhibited the haemolytic activity of the pathogen, as well as reduced the expression of Stx1, Stx2 and HlyA. The MbF1‐2 protein from the non‐glycosylated fraction was sequenced and identified as a homologue of the royal jelly‐like protein of Melipona quadrifasciata. Conclusions The non‐glycosylated protein fraction from M. beecheii honey greatly contributes to antibacterial activity and it is composed of at least three proteins, of which MbF1‐2 provided over 50% of the antimicrobial activity. Significance and Impact of the Study The study showed significant antimicrobial activity from several proteins present in the honey of M. beecheii. Interestingly, the non‐glycosylated protein fraction demonstrated antihaemolytic activity and adversely affected the expression of virulence genes in Escherichia coli O157:H7; these proteins have the potential to be used in developing therapeutic agents against this bacterium.