Pectic Polysaccharides from Roots ofGlycyrrhiza uralensis: Possible Contribution of Neutral Oligosaccharides in the Galacturonase-Resistant Region to Anti-Complementary and Mitogenic Activities

Abstract

Digestion with endo-alpha-(1-->4)-polygalacturonase liberated the enzyme-resistant region (PG-1c) as an active site of the anti-complementary and mitogenic pectic polysaccharide (GR-2IIc) from Glycyrrhiza uralensis. Partial acid hydrolysis of PG-1c resulted in acidic oligosaccharides, and methylation analysis and GC-MS analysis of the acidic oligosaccharides suggested that PG-1c comprised a rhamnogalacturonan core such as -->2)-Rha-(1-->4)-GalA-(1-->2)-Rha-(1-->4)-GalA-(1-->-->4)-GalA-(1-->4) as the acidic moiety. Degradation of uronic acids by lithium decreased the anti-complementary and mitogenic activities of PG-1c. Although the products from PG-1c were still active, the methylglycoside of alpha-L-Rha-(1-->4)-alpha-D-GalA-(1-->2)-alpha-L-Rha-(1-->4)-alpha-D-Gal A did not show both activities. The products obtained by the lithium degradation from PG-1c gave fractions containing various neutral oligosaccharide-alditols. Among these fractions the longest and the short oligosaccharide-alditol fractions had relatively potent anti-complementary activity, whereas all oligosaccharide-alditol fractions expressed weak but significant mitogenic activity. GC-MS analysis indicated that the short oligosaccharide-alditol fraction contained various kinds of di- to tetrasaccharide-alditols. However, malto-oligosaccharide-alditols, and malto-, isomalto-, and laminari-oligosaccharides did not show anti-complementary and/or mitogenic activities, and these results suggested that certain neutral carbohydrate chains in PG-1c were responsible for the expression of mitogenic activity as well as anti-complementary activity of PG-1c.

Biochemical Properties of Polysaccharides from Black Pepper

“…The component sugar analysis and the reaction to b-glucosyl Yariv reagent indicated that PN-IIa might contain arabinogalactan and acidic polysaccharides. These results were typical in anti-complementary pectic polysaccharides found in Bupleurum falcatum, 30) Glycyrrhiza uralensis 31) and Panax ginseng.…”

Pharmaceutical evaluation of liquorice before and after roasting in mice

“…immunologically active polysaccharides isolated from G. uralensis roots (Shimizu et al 1992;Kiyohara et al 1996).…”

Ping Wei San, a Chinese Medicine for Gastrointestinal Disorders

“…The licorice used in PWS (Glycyrrhiza uralensis [GRZ]) is honey roasted and is a different species of licorice (Glycyrrhiza glabra L.) than that found in most English texts. One in vitro study, 23 citing G. uralensis as a clinically useful treatment for inflammation, allergy, and gastric ulcer, showed that samples of the root had anticomplementary and mitogenic activities. Another study, 24 with mice, reported that liver microsomal cytochrome P450 induction by GRZ had much less effect than glycyrrhetinic acid (also found in G. glabra) alone.…”