Abstract
Amomum Villosum Lour. (A. villosum) is a folk medicine that has been used for more than 1300 years. However, study of the polysaccharides of A. villosum is seriously neglected. The objectives of this study are to explore the structural characteristics of polysaccharides from A. villosum (AVPs) and their effects on immune cells. In this study, the acidic polysaccharides (AVPG-1 and AVPG-2) were isolated from AVPs and purified via anion exchange and gel filtration chromatography. The structural characteristics of the polysaccharides were characterized by methylation, HPSEC-MALLS-RID, HPLC, FT-IR, SEM, GC-MS and NMR techniques. AVPG-1 with a molecular weight of 514 kDa had the backbone of → 4)-α-d-Glcp-(1 → 3,4)-β-d-Glcp-(1 → 4)-α-d-Glcp-(1 →. AVPG-2 with a higher molecular weight (14800 kDa) comprised a backbone of → 4)-α-d-Glcp-(1 → 3,6)-β-d-Galp-(1 → 4)-α-d-Glcp-(1 →. RAW 264.7 cells were used to investigate the potential effect of AVPG-1 and AVPG-2 on macrophages, and lipopolysaccharide (LPS) was used as a positive control. The results from bioassays showed that AVPG-2 exhibited stronger immunomodulatory activity than AVPG-1. AVPG-2 significantly induced nitric oxide (NO) production as well as the release of interleukin (IL)-6 and tumor necrosis factor alpha (TNF-α), and upregulated phagocytic capacities of RAW 264.7 cells. Real-time PCR analysis revealed that AVPG-2 was able to turn the polarization of macrophages to the M1 direction. These results suggested that AVPs could be explored as potential immunomodulatory agents of the functional foods or complementary medicine.
Highlights
Amomum villosum Lour. (Zingiberaceae, A. villosum) has been used as a traditional Chinese medicine for the treatment of gastrointestinal diseases for more than 1300 years [1]
AVPG-1 contained a higher content of total carbohydrate (88.74% vs. 64.06%) and protein (0.18% vs. 0.14%), while AVPG-2 contained higher contents of uronic acid (28.04% vs. 7.21%) and sulfate (1.06% vs. 0.69%)
It was reported that many biological activities, e.g., anti-oxidant activity, immunomodulatory activity and anti-tumor activity, were related to the molecular weight, sulfate content and uronic acid content of polysaccharides [20,21]
Summary
Amomum villosum Lour. (Zingiberaceae, A. villosum) has been used as a traditional Chinese medicine for the treatment of gastrointestinal diseases for more than 1300 years [1]. Accumulating studies demonstrated that the major bioactive components of A. villosum included volatile oils, flavonoids, terpenoids and polysaccharides, which showed anti-inflammation, anti-oxidant, antiulceration and anti-microbial activities [3,4,5,6,7,8,9]. Polysaccharides are macro-biomolecules that display a wide spectrum of biological and pharmacological activities, such as anti-oxidative, immunomodulatory, anti-tumor and hypoglycemic effects [10,11,12,13,14]. There are only a few studies concerning A. villosum polysaccharides (AVPs). On the market, A. villosum mostly comes from Yunnan province because the production from Yangchun cannot meet the increasing demand [19]. A thorough investigation into the structure, biological activities and structure-activity relationship of purified AVPs from other regions is required
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a call
