title: Characterization and in vitro immunomodulatory screening of fructo-oligosaccharides of Asparagus racemosus Willd.
abstract: Asparagus racemosus Linn. (Fam. Liliaceae) is an ethno-pharmacologically acclaimed Ayurvedic medicinal plant. In the present study, aqueous extract of A. racemosus (ARC) was fractionated and screened for the polysaccharide fraction (ARP). The characterization was done by enzymatic, Size Exclusion, gas chromatography with flame ionization detector (GC-FID), high pressure anion exchange chromatography (HPAEC) and thin layer chromatographic analyses. Phyto-chemical evaluation confirmed the presence of 26.7% of 2→1 linked fructo-oligosaccharides (FOS). They have a degree of polymerization (DP) of nearly 7-8. Cytotoxicity evaluation on P388 cell lines was consistent with low cytotoxicity of the extracts. In vitro Natural Killer (NK) cell activity was evaluated using human peripheral blood mononuclear cells (PBMC) isolated from whole blood on a ficoll-hypaque density gradient. K562 a myeloid leukemia cell line, were used as target cells. ARC, tested over the range 0.2-50 μg/ml, showed a dose-related stimulation of NK cell activity with a peak increase of 16.9±4.4% at 5.6 μg/ml. However, ARP demonstrated a higher stimulatory activity of 51.8±1.2% at 25 μg/ml. The results indicate that the FOS from A. racemosus potentiates the NK cell activity and this could be an important mechanism underpinning the 'Rasayana' properties of this plant.
authors: Centre for Phytochemistry and Pharmacology, Lismore, NSW 2480, Australia. mayankthakur25@gmail.com
authors: Mayank
authors: M
authors: Thakur
authors: Paul
authors: P
authors: Connellan
authors: Myrna A
authors: MA
authors: Deseo
authors: Carol
authors: C
authors: Morris
authors: Werner
authors: W
authors: Praznik
authors: Renate
authors: R
authors: Loeppert
authors: V K
authors: VK
authors: Dixit
mesh_terms: D000838:Anions; D027761:Asparagus Plant; D002849:Chromatography, Gas / Q000379:methods; D002850:Chromatography, Gel / Q000379:methods; D002852:Chromatography, Ion Exchange / Q000379:methods; D002855:Chromatography, Thin Layer / Q000379:methods; D003198:Computer Simulation; D005632:Fructose / Q000737:chemistry; D006801:Humans; D056747:Immunomodulation / Q000187:drug effects; D020128:Inhibitory Concentration 50; D020014:K562 Cells; D007694:Killer Cells, Natural / Q000166:cytology; D007963:Leukocytes, Mononuclear / Q000166:cytology; D046911:Macromolecular Substances / Q000737:chemistry; D009844:Oligosaccharides / Q000737:chemistry*; D008517:Phytotherapy / Q000379:methods; D011108:Polymers / Q000737:chemistry; D011134:Polysaccharides / Q000737:chemistry
chemical_list: D000838:Anions; D046911:Macromolecular Substances; D009844:Oligosaccharides; D011108:Polymers; D011134:Polysaccharides; D005632:Fructose