Antidiabetic activity of Musa x paradisiaca extracts in streptozotocin-induced diabetic rats and chemical characterization by HPLC-DAD-MS.

ETHNOPHARMACOLOGICAL RELEVANCE: The Musa x paradisiaca L. inflorescence, known as banana blossom or banana heart, is used in traditional medicine for the treatment of diabetes mellitus. AIM OF THE STUDY: The aim of the study was to investigate the antidiabetic activity of aqueous extracts and fractions prepared from the bracts and flowers of Musa x paradisiaca in streptozotocin (STZ)-induced diabetic rats and to chemically characterize the extracts. MATERIALS AND METHODS: Standard aqueous extracts of the flowers, bracts, and their fractions were prepared and their chemical composition was determined tentatively by high-performance liquid chromatography coupled to diode-array detection and mass spectrometry (HPLC-DAD-MS). Changes in fasting glycemia and oral glucose tolerance were evaluated in STZ-induced diabetic rats (n = 8) treated with aqueous extracts of Musa x paradisiaca (200 mg/kg) for 20 days. RESULTS: Chemical analyses detected 21 compounds and 17 metabolites were identified, among which were glycosylated and acetylated phenylpropanoids of p-coumaric acid and caffeic acid, as well as a glycosylated flavonol and anthocyanins. Following 15 days of treatment, the bract aqueous extracts and the methanolic fraction of the flower had significant effects on the glycemic profile after glucose load in diabetic rats as compared with the untreated diabetic group. CONCLUSIONS: The results of the present study show the antidiabetic potential of extracts of the flowers and bracts of M. x paradisiaca.

Acid diterpenes from Copaiba oleoresin (Copaifera langsdorffii): Chemical and plasma stability and intestinal permeability using Caco-2 cells.

ETHNOPHARMACOLOGICAL RELEVANCE: Copaiba oleoresin has been used in folk medicine in the treatment of bronchitis, syphilis, skin diseases and ulcers due to its anti-inflammatory and antiseptic activities, but there is no information about major compounds oral absorption to support the traditional use. AIM OF STUDY: Considering the potential of copalic (CA) and kaurenoic acid (KA) - major biological activity (in vitro) diterpenes found in the oleoresin, this study aimed to evaluate the intestinal permeability of CA and KA using Caco-2 cells model as predictive test for oral drug absorption. MATERIALS AND METHODS: Chemical stability at pH 1.2 and 7.4 and plasma stability were evaluated to mimic physiological conditions of the gastrointestinal tract. The intestinal permeability of CA and KA was evaluated in Caco-2 cells in the presence and absence of the P-glycoprotein inhibitor verapamil. RESULTS: CA and KA were rapidly degraded at pH 1.2 (0.2 M Clark-Lubs buffer). At pH 7.4 (0.1 M phosphate buffer), CA was stable for up to 24 h and KA for up to 6 h. In human plasma, CA and KA can be considered stable for 24 h and 12 h at 37 °C, respectively. Caco-2 cells were considered viable when incubated with CA or KA in the range of 3.9-250 µM for 24 h. CA and KA exhibited moderate apparent permeability (Papp) of 4.67 (±0.08) × 10-6 cm/s and 4.66 (±0.04) × 10-6 cm/s, respectively. Simultaneous incubation with verapamil showed that P-glycoprotein does not play a relevant role on CA and KA oral absorption, with Papp of 4.48 (±0.26) × 10-6 cm/s and 5.37 (±0.72) × 10-6 cm/s observed for CA and KA, respectively. CONCLUSION: The oral absorption of both CA and KA is driven by mainly passive permeability, is not limited by p-glycoprotein, but enteric-coated dosage forms should be used to avoid chemical instability in the gastric pH.

Green coffee seed residue: A sustainable source of antioxidant compounds.

Oil extraction from green coffee seeds generates residual mass that is discarded by agribusiness and has not been previously studied. Bioactive secondary metabolites in coffee include antioxidant phenolic compounds, such as chlorogenic acids. Coffee seeds also contain caffeine, a pharmaceutically important methylxanthine. Here, we report the chemical profile, antioxidant activity, and cytotoxicity of hydroethanolic extracts of green Coffea arabica L. seed residue. The extracts of the green seeds and the residue have similar chemical profiles, containing the phenolic compounds chlorogenic acid and caffeine. Five monoacyl and three diacyl esters of trans-cinnamic acids and quinic acid were identified by ultra-performance liquid chromatography/electrospray ionization-quadruple time of flight mass spectrometry. The residue extract showed antioxidant potential in DPPH, ABTS, and pyranine assays and low cytotoxicity. Thus, coffee oil residue has great potential for use as a raw material in dietary supplements, cosmetic and pharmaceutical products, or as a source of bioactive compounds.