Isolation of Sulfated Galactan from Codium fragile and Its Antiviral Effect

• Published in: Biological & Pharmaceutical Bulletin Vol. 32; no. 5; pp. 892 - 898
• Main Authors: Ohta, Yuko, Lee, Jung-Bum, Hayashi, Kyoko, Hayashi, Toshimitsu
• Format: Journal Article
• Language: English
• Published: Japan The Pharmaceutical Society of Japan 01.05.2009; Pharmaceutical Society of Japan; Japan Science and Technology Agency
• Subjects: Animals; Antiviral Agents - adverse effects; Antiviral Agents - isolation & purification; Antiviral Agents - pharmacology; Antiviral Agents - therapeutic use; Cell Survival - drug effects; Cercopithecus aethiops; Chlorophyta - chemistry; Codium fragile; Dogs; Female; Galactans - adverse effects; Galactans - isolation & purification; Galactans - pharmacology; Galactans - therapeutic use; Herpes Genitalis - drug therapy; Herpes Genitalis - virology; Herpes simplex virus 2; herpes simplex virus type 2; Herpesvirus 2, Human - drug effects; Influenza A Virus, H1N1 Subtype - drug effects; Mice; Mice, Inbred BALB C; pyruvylated-sulfated galactan; Sulfates; Vero Cells; Virus Replication - drug effects
• ISSN: 0918-6158; 1347-5215
• DOI: 10.1248/bpb.32.892

A sulfated galactan (FG) was isolated from the green alga, Codium fragile. Chemical analysis revealed that FG mainly consisted of D-galactose with pyruvic acid (12.3%) and sulfate (11.0%). Methylation and NMR analyses showed that FG was composed of →3)-β-D-Galp-(1→, β-D-Galp-(1→ and →3,6)-β-D-Galp-(1→ residue. In addition, pyruvic acid was suggested to be present as (1′-carboxy)-ethylidene cyclic ketal at O-3 and O-4 of non-reducing terminal galactose residues, whereas sulfate was substituted at O-4 of other galactose residues. When the antiviral potency of FG was evaluated, it inhibited the replication of herpes simplex virus type 2 (HSV-2), and the mechanism of action was suggested to be interference in the early steps such as virus adsorption to and penetration into host cells. Furthermore, it was shown that FG directly reduced virus infection rates. In a genital infection model using HSV-2-infected mice, FG improved mortality and lesion scores and reduced virus yields by intravaginal administration. These results suggest that FG might be a potent candidate as a prophylactic agent for HSV-2 infection.