BackgroundThe increasing numbers of people who use plant-based remedies as alternative or complementary medicine call for the validation of less known herbal formulations used to treat their ailments. Since Puerto Rico has the highest rate of Type 2 diabetes within all the states and territories of the United States, and Puerto Ricans commonly use plants as diabetes adjuvants, it is important to study the plants’ physiological effects, and identify their bioactive compounds to understand their role in modulation of blood glucose levels. We present the phytochemical profiles and hypoglycemic effects of Tapeinochilus ananassae, Costus speciosus and Syzygium jambos.MethodsPhytochemicals in methanolic and aqueous extracts were analyzed by thin layer chromatography (TLC). Alkaloids (Bromocresol green, λ = 470 nm), flavonoids (AlCl3, λ = 415 nm), saponins (DNS, λ = 760 nm), tannins (FeCl3/K4Fe(CN)6, λ = 395 nm) and phenolics (Folin-Ciocalteau, λ = 765 nm) were quantified. Male C57BLKS/J (db/db) and C57BL/J (ob/ob) genetically obese mice were orally gavaged with aqueous extracts of lyophilized plant decoctions for 10wks.ResultsOur results show that T. ananassae had significantly greater amounts of flavonoids and tannins, while S. jambos showed the greatest concentration of phenolics and C. speciosus exhibited higher amounts of alkaloids. C57BLKS/J db/db treated with plant extracts show better glucose modulation when the extracts are administered in complement with an insulin injection. Finally, C57BL/J ob/ob mice on T. ananassae and S. jambos treatments show better blood glucose modulation over time.ConclusionThese results document for the first time the chemical profile of T. ananassae and provide evidence for a potential anti-diabetic efficacy of T. ananassae and S. jambos.Electronic supplementary materialThe online version of this article (doi:10.1186/s12906-015-0772-7) contains supplementary material, which is available to authorized users.

BackgroundThe TRAMIL program aims to understand, validate and expand health practices based on the use of medicinal plants in the Caribbean, which is a “biodiversity hotspot” due to high species endemism, intense development pressure and habitat loss. The antibacterial activity was examined for thirteen plant species from several genera that were identified as a result of TRAMIL ethnopharmacological surveys or were reported in ethnobotanical accounts from Puerto Rico. The aim of this study was to validate the traditional use of these plant species for the treatment of bacterial infections, such as conjunctivitis, fever, otitis media and furuncles.MethodsAn agar disc diffusion assay was used to examine five bacterial strains that are associated with the reported infections, including Staphylococcus saprophyticus (ATCC 15305), S. aureus (ATCC 6341), Escherichia coli (ATCC 4157), Haemophilus influenzae (ATCC 8142), Pseudomonas aeruginosa (ATCC 7700) and Proteus vulgaris (ATCC 6896), as well as the fungus Candida albicans (ATCC 752). The minimum inhibitory concentration (MIC) and minimum bactericidal concentration (MBC) values were determined for each of the extracts that showed inhibitory activity.ResultsThe decoctions of Pityrogramma calomelanos, Tapeinochilus ananassae, and Syzygium jambos, as well as the juice of Gossypium barbadense, showed > 20% growth inhibition against several bacteria relative to the positive control, which was the antibiotic Streptomycin. Extracts with the best antimicrobial activities were S. jambos that showed MIC = 31 μg/mL and MBC = 1.0 mg/mL against P. vulgaris and T. ananassae that showed MIC = 15 μg/mL against S. aureus.ConclusionThis report confirms the traditional use of P. calomelanos for the treatment of kidney infections that are associated with stones, as well as the antimicrobial and bactericidal effects of T. ananassae against P. vulgaris and S. saprophyticus and the effects of S. jambos against S. aureus and S. saprophyticus.