In vitro anti-human immunodeficiency virus activity of polysaccharide fromRhizophora mucronata Poir.

A polysaccharide was extracted with 1% sodium carbonate from the bark of Rh izophora mucronata and ifs antiviral activities against human immunodeficie ncy virus (HIV) were assessed by an in vitro cell culture system, The anti- HIV activity of the alkaline extract was mainly recovered in the 25-75% eth anol-precipitated fraction. Rhizophora mucronata polysaccharide (RMP) prote cted MT-4 cells from the HIV-induced cytopathogenicity and blocked the expr ession of HIV antigens. RMP completely inhibited the viral binding to the c ell and the formation of syncytium upon cocultivation of MOLT-4/HIV-1, cell s and MOLT-4 cells. These results suggest that RMP inhibited early steps of the virus life cycle especially virus adsorption to the cell.