The mode of action of the anxiolytic medicinal plant Souroubea sympetala was investigated to test the hypothesis that extracts and the active principle act at the pharmacologically important GABAA-benzodiazepine (GABAA-BZD) receptor. Leaf extracts prepared by ethyl acetate extraction or supercritical extraction, previously determined to have 5.54 mg/g and 6.78 mg/g of the active principle, betulinic acid, respectively, reduced behavioural parameters associated with anxiety in a rat model. When animals were pretreated with the GABAA-BZD receptor antagonist flumazenil, followed by the plant extracts, or a more soluble derivative of the active principle, the methyl ester of betulinic acid (MeBA), flumazenil eliminated the anxiety-reducing effect of plant extracts and MeBA, demonstrating that S. sympetala acts via an agonist action on the GABAA-BZD receptor. An in vitro GABAA-BZD competitive receptor binding assay also demonstrated that S. sympetala extracts have an affinity for the GABAA-BZD receptor, with an EC50 value of 123 μg/mL (EtOAc leaf extract) and 154 μg/mL (supercritical CO2 extract). These experiments indicate that S. sympetala acts at the GABAA-BZD receptor to elicit anxiolysis.

This study investigated the potential of Northern shrimp (Pandelus borealis Kreyer) by-products as a source of omega-3 polyunsaturated fatty acids (ω-3 PUFAs). The by-products (heads, shell and tail) of processing accounted for approximately 50–60% of the catch. Supercritical CO2 extraction (SFE) of the by-products at 35 MPa and 40 °C generated a deep red oil, rich in ω-3 PUFAs, specifically 7.8 ± 0.06% eicosapentaenoic acid (EPA) and 8.0 ± 0.07 % docosahexaenoic acid (DHA).

The purpose of this work was to develop an extraction technique to yield a betulinic acid-(BA) enriched extract of the traditional anti-anxiety plant Souroubea sympetala Gilg (Marcgraviaceae). Five extraction techniques were compared: supercritical carbon dioxide extraction (SCE), conventional solvent extraction with ethyl acetate (EtOAc), accelerated solvent extraction (ASE), ultrasonic assisted extraction (UAE) and soxhlet extraction (Sox). The EtOAc and SCE extraction methods resulted in BA-enriched extracts, with BA concentrations of 6.78 +/- 0.2 and 5.54 +/- 0.2 mg/g extract, respectively, as determined by HPLC-APCI-MS. The bioactivity of the BA-enriched extracts was compared in the elevated plus maze (EPM), a validated rodent anxiety behaviour assay. Rats orally administered a 75 mg/kg dose of SCE extract exhibited anxiolysis as compared with vehicle controls, with a 50% increase in the percent time spent in the open arms, a 73% increase in unprotected head dips and a 42% decrease in percent time spent in the closed arms. No significant differences were observed between the SCE and EtOAc extracts for these measures, but the animals dosed with SCE extract had significantly more unprotected head dips than those dosed with the EtOAc extract. The SCE extract demonstrated a dose-response in the EPM, with a trend toward decreased anxiety at 25 mg/kg, and significant anxiolysis was only observed at 75 mg/kg dose. This study demonstrates that SCE can be used to generate a betulinic acid-enriched extract with significant anxiolysis in vivo. Further, the study provides a scientific basis for the ethnobotanical use of this traditional medicine and a promising lead for a natural health product to treat anxiety. Copyright (C) 2010 John Wiley & Sons, Ltd.

A rapid, two-solvent, HPLC-APCI-MS method was developed to identify and quantify four pentacyclic triterpenes (betulinic acid, ursolic acid, α-amyrin and β-amyrin) in extracts of the neotropical medicinal plant Souroubea sympetala. Analysis of plant organs, wood, bark, leaves, immature fruit and flowers, indicated that the phytochemical distribution and quantity of triterpenes varies across the plant, with betulinic acid and ursolic acid the major constituents in the bark, wood, fruit and flowers and the amyrins the major constituents of the leaves.

A rapid, two-solvent, HPLC-APCI-MS method was developed to identify and quantify four pentacyclic triterpenes (betulinic acid, ursolic acid, α-amyrin and β-amyrin) in extracts of the neotropical medicinal plant Souroubea sympetala. Analysis of plant organs, wood, bark, leaves, immature fruit and flowers, indicated that the phytochemical distribution and quantity of triterpenes varies across the plant, with betulinic acid and ursolic acid the major constituents in the bark, wood, fruit and flowers and the amyrins the major constituents of the leaves.