Intestinal Immune Modulating Polysaccharides of Atractylodes lancea DC. Rhizomes

  • Yu, Kwang-Won (Graduate School of Biotechnology, Korea University)
  • Published : 2000.05.01

Abstract

A kind of traditional herbal prescription, Sip-Jeon-Dae-Bo-Tang (TJ-48), has been reported to improve the general condition of cancer patients receiving chemotherapy and /or radiation therapy, and to accelerate hematopoietic recovery from bone marrow injury by mitomycin C. In the present studies, we found that hot-water extract from Atractylodes lancea DC. rhizomes contributed mainly to intestinal immune modulating activity of TJ-48 on Peyer's patch cells mediated-hematopoietic response. After the fractionation, ALR-5 II a-1-1, 5 II b-2-2 and 5 II c-3-1 were further purified from crude polysaccharide fraction. Chemical analyses of each fraction indicated that ALR-5 II a-1-1 mainly contained arabinogalactan fraction whereas ALR-5 II b-2-2 and 5 II c-3-1 mostly comprised pectic polysaccharide fractions as the active polysaccharide ingredients. In order to analyze the essential structure of the activity, ALR-5 II a-1-1 was treated by sequential enzymatic digestion using exo-${\alpha}$-L-arabinofuranosidase and exo-${\beta}$-D-(1\longrightarrow3)-galactanase. Based upon the results of chemical and MALDI-TOF-MS analyses and activity on the digested fractions, the galactosyl side chains consisting of 6-linked Galf and Galp over tetrasaccharide in ALR-5 II a-1-1 might be responsible for the potent intestinal immune modulating activity. To characterize moiety of ALR-5 II c-3-1 for the expression of activity, endo-${\alpha}$-D-(1\longrightarrow4)-polygal acturonase (GL-PGase) purified from dried leaves of Panax ginseng digested ALR-5 II c-3-1. The results of structural analyses and activity on the digested fractions showed that PG-2, which structurally resembles to rhamnogalacturonan II (RG II), and PG-3 (galacturono-oligosaccharides) contained potent intestinal immune modulating activity. Further purification of the other acidic fraction (ALR-5 II b-2-2) indicated that ALR-5 II b-2-2Bb showed that the most potent activity. ALR-5 II b-2-2Bb also contained the unusual component sugars characteristics in RG- II as well as PG-2 derived from ALR-5 II c-3-1, but it could not be digested with GL-PGase. The present studies of relationship between structures and intestinal immune modulating activity of the active polysaccharides purified from A. lancea DC. rhizomes suggested that neutral galactosyl chains consisting mainly of (1\longrightarrow6)-linked Galf and Galp, and RG- II -like moiety with unique component sugars, such as 2-Me-Xyl, 2-Me-Fuc, Api, AceA, Kdo and Dha should play an important role in the potent intestinal immune modulating action of A. lancea DC. rhizomes.

Keywords