Chemical constituents of açai berry pulp (Euterpe oleracea Mart.) by LC-UV-BPSU/NMR and LC-UV-SPE/NMR.

The techniques LC-UV-BPSU and LC-UV-SPE/NMR were applied for the first time in the analysis of açai berry (Euterpe oleracea Mart.) pulp extracts. Those techniques allowed the identification of twenty-three metabolites: Valine (1), citric acid (2), tachioside (3), isotachioside (4), α-guaiacylglycerol (5), syringylglycerol (6), uridine (7), adenosine (8), dimethoxy-1,4-benzoquinone (9), koaburaside (10), protocatechuic acid (11), eurycorymboside B (12), 7',8'-dihydroxy-dihydrodehydroconiferyl alcohol-9-O-ß-D-glucopyranoside (13), orientin (14), homoorientin (15), dihydrokaempferol-3-glucoside (16), isolariciresinol-9'-O-ß-D-glucopyranoside (17), 5'-methoxyisolariciresinol-9'-O-ß-D-glucopyranoside (18), cyanidin-3-O-glucoside (19), cyandin-3-O-rutenoside (20), 9,12-octadecadienoic acid (Z,Z)-2-hydroxy-1-(hydroxymethyl) ethyl ester (21), linolenic acid (22), and 1,2-di-O-α-linolenoyl-3-O-ß-D-galactopyranosyl-sn-glycerol (23). In this plant, compounds 3, 4, 5, 6, 8, 10, 12, 17, 18, 21, and 23 are reported for the first time. All the structures were determined through extensive analyses of 1D and 2D NMR data, mass spectrometry, and comparison with published data. This methodology has proven to be an efficient alternative to the analysis of complex extracts containing a large variety of compounds.

The effect of indomethacin and reserpine on renal vascular escape.

Isolated rabbit kidneys were perfused with Krebs-Henseleit solution in an open system designed to allow study of dose-response relationships. The effects of the cyclooxygenase inhibitor indomethacin and of reserpine on (norepinephrine) noradrenaline (NOR)-induced renal vascular escape were studied. Indomethacin (50 mg/Kg) was given two hours prior to surgery followed by continuous infusion (0.33 mg/min), and blocked renal vascular escape in all doses of NOR tested (10(-7)-10(-4) M) by 70-80%. Reserpine (10 mg/Kg, given 10-12 hours prior to organ perfusion), also suppressed renal vascular escape significantly by 80-90%. We conclude that there is a participation of prostaglandins in noradrenaline induced escape in the perfused rabbit kidney.

An acid extract from dissociation medium of sea urchin embryos, induces mesenchyme differentiation.

When material extracted by 1 M acetic acid from the dissociation medium of sea urchin embryos is added at low concentrations to isolated primary mesenchyme cells, it induces skeletogenesis. The same material added to dissociated blastula cells, or to embryos at the blastula stage, stimulates skeleton formation and pigment cell differentiation. On dissociated cells, it also increases cell reaggregation, thymidine incorporation and survival. On embryos, it induces exogastrulation and appearance of extraembryonic pigment cells. The activity of the extract is resistant to raised temperatures and partially to tryptic digestion but is abolished by trypsin treatment followed by heating. The active fraction does not readily filter through Amicon XM-50 and is retarded by column chromatography on Bio-Gel P-60.