Sulfated modification and anti-tumor activity of laminarin

Abstract

The aim of this study was to investigate the sulfated modification of laminarin and the changes in structure and antitumor activity. The chlorosulfonic acid-pyridine method was applied for sulfated modification. The molecular weights of laminarin and laminarin sulfate (LAMS) were measured by high-performance liquid chromatography (HPLC), and IR and NMR spectra were also recorded. The surface conformations of laminarin and LAMS were observed with a scanning electron microscope. The antitumor activities of the two polysaccharides were also evaluated using an MTT assay. LAMS with a sulfate content of 45.92% and a molecular weight of 16,000 was synthesized. The IR spectra of laminarin and LAMS showed the characteristic absorption peaks of a polysaccharide, and LAMS also had the characteristic absorption peaks of sulfate moieties. The NMR spectra showed that laminarin and LAMS had β-(1→3) glycosidic bonds forming the main chain, and sulfate substitution was at the hydroxyl groups of C2 and C6. Under the scanning electron microscope, there were clear differences in surface conformation between laminarin and LAMS; laminarin was cloud-like and spongy, while LAMS was block-like and flaky. The MTT results showed that laminarin and LAMS had inhibitory effects on LoVo cell growth, and the antitumor activity of LAMS was higher than that of laminarin at the same concentration. This suggests that sulfated modification was able to change the laminarin structure and markedly enhance the antitumor activity.

Antimicrobial Properties and Cytotoxicity of Sulfated (1,3)-��-D-Glucan from the Mycelium of the Mushroom Ganoderma lucidum

“…4, respectively. The current work is comparable with previous research by Ji et al, [16], which analyzed laminarin and sulfated laminarin in the area of 1 H-NMR spectrum of δ 4.49-5.5 ppm. Thus, these spectra indicate that the glycosidic bonds in both G (Fig.…”

FTIR characterization and antioxidant activity of water soluble crude polysaccharides of Sri Lankan marine algae

“…3A) in SLBS11P and fucoidan standard indicates stretching vibrations of the glycosidic C─O group of fucoidan. The broadened peak between 1,120-1,270 cm -1 indicate sulfate groups (S═O RB3LYP/6-31G(d,p) level and based on relevant literature (Tul'chinsky et al 1976, Christiaen and Bodard 1983, Mathlouthi and Koenig 1987, Mollet et al 1998, Roberts and Quemener 1999, Marais and Joseleau 2001, Pereira et al 2003, Chandía et al 2004, Praiboon et al 2006, Leal et al 2008, Alves et al 2010, Ji et al 2013, Xia et al 2014). Fig.…”

Biological and therapeutic properties of the seaweed polysaccharides

“…Their results revealed that incubation of cancer cells with laminaran (400-1600 μg/mL) for 72 h induces apoptosis in LoVo cells. Additionally, Ji et al [248] studied anticancer activity of laminaran after modifying the sulfate content of laminaran by the chlorosulfonic-acid-pyridine method. The authors compared the anticancer effects of normal and modified laminaran on LoVo cells by the 3-(4,5-dimethylthiazol-2-yl)-2,5diphenyltetrazolium bromide (MTT) assay.…”

“…However, at the same concentration, unmodified laminaran could reduce the cancer cell number by only 38%. Thus, the authors proposed that sulfation of the structure might increase bioactivities of laminaran [248].…”