Bioactive Benzofuran Derivatives from Cortex Mori Radicis, and Their Neuroprotective and Analgesic Activities Mediated by mGluR1.

Four new benzofuran-type stilbene glycosides and 14 known compounds including 8 benzofuran-type stilbenes and 6 flavonoids were isolated from the traditional Chinese medicine, Cortex Mori Radicis. The new compounds were identified as (9R)-moracin P 3'-O-α-l-arabinopyranoside (1), (9R)-moracin P 9-O-ß-d-glucopyranoside (2), (9R)-moracin P 3'-O-ß-d-glucopyranoside (3), and (9R)-moracin O 10-O-ß-d-glucopyranoside (4) based on the spectroscopic interpretation and chemical analysis. Three benzofuran-type stilbenes, moracin O (5), R (7), and P (8) showed significant neuroprotective activity against glutamate-induced cell death in SK-N-SH cells. In addition, moracin O (5) and P (8) also demonstrated a remarkable inhibition of the acetic acid-induced pain. The molecular docking with metabotropic glutamate receptor 1 (mGluR1) results indicated that these neuroprotective benzofuran-type stilbenes might be the active analgesic components of the genus Morus, and acted by mediating the mGluR1 pathway.

[Quality standard study on Mori Cortex liquid extract].

A reasonable and practicable quality standard was developed for mori liquid extract from different sources by TLC, HPLC and fingerprint technology. In TLC method, the compounds were separated on polyamide film using glacial acetic acid-water (1: 3) as mobile phase at a UV wavelength of 365 nm. All qualified samples had the spots of the same color as the control herb and substance. The RP-HPLC method was used to determine the content of mulberroside A with mobile phase of methanol-water (25: 75) at a wave-length of 326 nm. The mulberroside A was in good linear with a regression equation of Y = 46.965X (r = 0.999 6) in the range of 4.6 - 228 mg x L(-1). In 14 batches of samples, the mulberroside A in 4 batches of them was less than 0.5 g x L(-1), and was more than 2.0 g x L(-1) in the other batches. It was suggested that the content limit of mulberroside A should be no less than 1.5 g x L(-1). The HPLC fingerprints were evaluated by the similarities. It has found that the similarities of different mori liquid extracts were very low and the chemical diversity of mori cortex was the major factor of similarity. Moreover, the process impact was minimal. Thus the fingerprint was not included in this quality standard.