Significance of metal ion supplementation in the fermentation medium on the structure and anti-tumor activity of Tuber polysaccharides produced by submerged culture of Tuber melanosporum

- The structures and anti-tumor activities of Tuber polysaccharides were studied.
- Intracellular polysaccharides were lower Mw when Mg2+ and K+ were used.
- Intracellular polysaccharides were lower Mw enhanced anti-tumor activity.
- Extracellular polysaccharides were compact spherical chains when K+ was used.
- Extracellular polysaccharides with compact promoted anti-tumor activity.