Extraction of functional natural products employing microwave-assisted aqueous two-phase system: application to anthocyanins extraction from mulberry fruits.

Aqueous two-phase extraction (ATPE) has been extensively utilized for the extraction and separation of tiny-molecule substances as a new system (system with short-chain ethanol and inorganic salts). In this study, an innovative method of extracting anthocyanins from mulberry was developed, employing microwave-assisted extraction with ethanol/ammonium sulfate as a biphasic extractant. Response surface methodology (RSM) was utilized to optimize anthocyanin extraction conditions: 39% ethanol (w/w), 13% ammonium sulfate (w/w), and liquid-to-solid ratio of 45:1, microwave duration 3 min, microwave temperature 32 °C, and microwave power 480 Watt (W). High-performance liquid chromatography (HPLC) analysis demonstrated no significant differences in the structure of mulberry anthocyanins before and after MAATPE treatment, furthermore. The extraction behavior of MAATPE was due to hydrogen bonding, according to Fourier transform infrared spectroscopy (FT-IR). Scanning electron microscopy analysis found that MAATPE damaged the cell structure via a microwave enhancement effect, which was more favorable to anthocyanin dissolution than standard extraction methods. The DPPH free radical scavenging rate of mulberry extracts at 0.5 mg/mL was higher than that of vitamin C (96.4 ± 0.76%), and the ABTS free radical scavenging rate (82.52 ± 2.13%) was close to that of vitamin C, indicating that MAATPE-derived mulberry extracts have good antioxidant activity.

Acanthophoraine A, a new pyrrolidine alkaloid from the red alga Acanthophora spicifera.

A new pyrrolidine alkaloid, acanthophoraine A (1), along with six known alkaloids (2-7), had been isolated from the red alga Acanthophora spicifera. The structures of these compounds were identified by spectroscopic analyses. The absolute configuration of 1 was established by ECD calculation. Compound 1 represents the first example of N-isobutyl pyrrolidone with an urea arm. The antimicrobial activity of 1 was also evaluated.[Figure: see text].

Allergic identification for ginkgo kernel protein in guinea pigs.

Ginkgo biloba L. can cause allergic reactions when consumed. In this paper, an allergy test to guinea pig was investigated. Guinea pigs were sensitized with 50 mg/mL of ginkgo kernel protein orally on days 1, 3, and 5, and intraperitoneally challenged with 100mg/mL of the protein on day 7 after the last sensitization. The volume of sensitization and challenge was 0.20mL/100 g weight. The results showed the average allergy grade for guinea pigs reached four and the allergy rate was 100%. The immunoglobulin G and E levels in sera were significantly higher than those in the controls. Footpads swelled distinctly, and the passive cutaneous allergy test manifested a positive response. There were inflammatory changes in the lungs and intestines. In conclusion, the present results may indicate that gingko kernel protein has an allergenic capacity.

[Effect of pulchinenoside in regulating FLS SFRP2 expression of RA model rats].

OBJECTIVE: To study the effect of pulchinenoside (PULC) in modulating SFRP2 expression in fibroblast-like synoviocytes (FLS) of rheumatoid arthritis (RA) model rats. METHOD: The effect of PULC in treating RA rats was evaluated by rat arthritis score and paw swelling score. The inhibitory effect of PULC on FLS proliferation was detected by MTT reagent. The effects of PULC gavage treatment in modulating gene expression of FLS SFRP2, critical gene beta-catenin of Wnt pathway and downstream effector genes C-myc of of Wnt pathway were detected by RT-PCR and Western blotting. RESULT: PULC had a significant effect in treating RA rats and that SFRP2 expression was down-regulated in FLS. After PULC gavage treatment, FLS SFRP2 expression was obviously up-regulated, whereas beta-catenin and C-myc gene expressions were significantly down-regulated. CONCLUSION: PULC can inhibit abnormal proliferation of synovial membrane by modulating Wnt pathway of RA rats.