Inhibition of HIV-1 replication by an aqueous extract of Spirulina platensis (Arthrospira platensis)

Seyoum Ayehunie(1), Amha Belay (2), Timothy Baba(1,3) and Ruth Ruprecht(1).

(1) Laboratory of Viral Pathogenesis, Dana-Farber Cancer Institute and Harvard Medical School, Boston, MA, USA; (2) Earthrise Farms, Calipatria, CA; (3) Division of Newborn Medicine, Department of Pediatrics, Tufts University, Boston, MA, USA.

An aqueous extract of the blue-green filamentous algae Arthrospira platensis (previously called Spirulina platensis) inhibited HIV-1 replication in human T-cell lines, peripheral blood mononuclear cells (PBMC) and Langerhans cells (LC). Extract concentrations ranging between 0.3 and 1.2 mcg/ml reduced viral production by approximately 50% (50% effective concentration [EC50] in PBMCs). The 50% inhibitory concentration (IC50) of extract for PBMC growth ranged between 0.8 and 3.1 mg/ml. Depending on the cell type used, therapeutic indices ranged between 200 and 6000. The extract inactivated HIV-1 infectivity directly when preincubated with virus before addition to human T-cell lines. Fractionation of the extract revealed antiviral activity in the polysaccharide fraction and also in a fraction depleted of polysaccharides and tannins. We conclude that aqueous A platensis extracts contain antiretroviral activity that may be of potential clinical interest.

PUB: Journal of Acquired Immune Deficiency Syndromes and Human Retrovirology, 18:7-12, 1998.

Calcium Spirulan, an inhibitor of enveloped virus replication, from a blue-green alga Spirulina

Hayashi et al. 1996, Japan.

Bioactivity-directed fractionation of a hot H2O extract from a blue-green-alga Spirulina platensis led to the isolation of a novel sulfated polysaccharide named Calcium Spirulan (Ca-SP) as an antiviral principle. This polysaccharide was composed of rhamnose, ribose, mannose, fructose, galactose, xylose, glucose, glucuronic acid, galacturonic acid, sulfate and calcium. Ca-SP was found to inhibit the replication of several enveloped viruses, including Herpes simplex virus type 1, human cytomegalovirus, measles virus, mumps virus, influenza A virus and HIV-1. It was revealed that Ca-SP selectively inhibited the penetration of virus into host cells. Retention of molecular conformation by chelation of calcium ion with sulfate groups was suggested to be indispensible to its antiviral effect.

PUB: Journal of Natural Products, 59, 83-87.

An extract from spirulina is a selective inhibitor of herpes simplex virus Type 1 Penetration into HeLa Cells

Hayashi et al. 1993, Japan.

The water soluble extract of spirulina achieved a dose-dependent inhibition of the replication of herpes simplex virus type 1 (HSV-1) in HeLa cells within the concentration range of 0.08-50 mg/mL. This extract proved to have no virucidal activity and did not interfere with adsorption to host cells. However, the extract affected viral penetration in a dose-dependent manner. At 1 mg/ml the extract was found to inhibit virus-specific protein synthesis without suppressing host cell protein synthesis if added to the cells 3 hours before hamsters at doses of 100 and 500 mg/kg per day.

PUB: Phytotherapy Research, Vol. 7. 76-80.

Antiviral activity of blue-green algae cultures

Patterson. 1993, USA.

Lipophilic and hydrophilic extracts from approximately 600 strains of cultured cyanophytes, representing some 300 species, were examined for antiviral activity against three pathogenic viruses. Approximately 10% of the cultures produced substances that caused significant reduction in cytopathic effect normally associated with viral infection. The screening program identified Chroocococcales as commonly producing antiviral agents. Key index words: antiviral, cyanobacteria, cyanophyte, herpes virus, HIV-1, HIV-2, human immunodeficiency virus, natural products, pharmaceutical, respiratory syncytical virus.

PUB: Journal of Phycology 29, 125-130.

AIDS Antiviral sulfolipids from cyanobacteria (blue-green algae)

K. R. Gustafson, J. H. Cardellina II, R. W. Fuller, K. M. Snader, M. R. Boyd, Developmental Therapeutics Program, Division of Cancer Treatment, National Cancer Institute, Bethesda, MD.
O. S. Weislow, R. F. Kiser, Program Resources, Inc., NCI-Frederick Cancer Research Facility, Frederick, MD.

G. M. L. Patterson, Department of Chemistry, University of Hawaii, Honolulu, HI.

August 16, 1989, USA

Sulfoglycolipids from blue-green algae exhibit strong antiviral properties. Helper T-cells exposed to blue-green algae-sulfoglycolipids were protected from HIV-1 infection in in vitro studies.

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A recently developed tetrazolium-based microculture assay was used to screen extracts of cultured cyanobacteria (blue-green algae) for inhibition of the cytopathic effects of the human immunodeficiency virus (HIV-1), which is implicated as a causative agent of AIDS.

A number of extracts were found to be remarkably active against the AIDS virus. A new class of HIV-1-inhibitory compounds, the sulfonic acid-containing glycolipids, was discovered through the use of the micro-culture assay to guide the fractionation and purification process.

The pure compounds were active against HIV-1 in cultured human lymphoblastoid CEM, MT-2, LDV-7, and C3-44 cell lines in the tetrazolium assay as well as in p24 viral protein and syncytium formation assays.

PUB: Journal of the National Cancer Institute, 81(16) pg. 1254-1258.

Action of Spirulina platensis on bacterial viruses

Gorobets OB, Blinkova LP, Baturo AP.

Mechnikov Research Institute for Vaccines and Sera, Moscow, Russia.

The impact of the biomass of the blue-green microalga (cyanobacterium) S. platensis on bacteriophage T4 (bacterial virus) has been evaluated. The study revealed that the addition of S. platensis biomass into the agar nutrient medium, followed by sterilization with 2% chloroform and thermal treatment, produced an inhibiting or stimulating effect on the reproduction of the bacteriophage in Escherichia coli B cells, depending on the concentration of S. platensis and the multiplicity of phage infection, as well as on the fact whether the microalgae were added during the first cycle of the development of the virus. The reproduction of the bacteriophage in E. coli B was influenced by the method and duration of the sterilization of the nutrient medium with S. platensis.

PUB: Zh Mikrobiol Epidemiol Immunobiol. 2002 Nov-Dec;(6):18-21.

Algae - a poor man's HAART?

Teas J, Hebert JR, Fitton JH, Zimba PV.

Health Promotion Education and Behavior, The Norman J. Arnold School of Public Health, University of South Carolina and the South Carolina Cancer Center, Columbia, USA.

Drawing inferences from epidemiologic studies of HIV/AIDS and in vivo and in vitro HIV inhibition by algae, we propose algal consumption as one unifying characteristic of countries with anomalously low rates. HIV/AIDS incidence and prevalence in Eastern Asia ( approximately 1/10,000 adults in Japan and Korea), compared to Africa ( approximately 1/10 adults), strongly suggest that differences in IV drug use and sexual behavior are insufficient to explain the 1000-fold variation. Even in Africa, AIDS/HIV rates vary. Chad has consistently reported low rates of HIV/AIDS (2-4/100). Possibly not coincidentally, most people in Japan and Korea eat seaweed daily and the Kanemba, one of the major tribal groups in Chad, eat a blue green alga (Spirulina) daily. Average daily algae consumption in Asia and Africa ranges between 1 and 2 tablespoons (3-13 g). Regular consumption of dietary algae might help prevent HIV infection and suppress viral load among those infected.

PUB: Med Hypotheses. 2004;62(4):507-10.

Inhibition of enterovirus 71-induced apoptosis by allophycocyanin isolated from a blue-green alga spirulina platensis

Shin-Ru Shih 1, Kun-Nan Tsai 1, Yi-Shuane Li 1, Chuang-Chun Chueh 2, Err-Cheng Chan1*

Enterovirus 71 infection causes significant morbidity and mortality in children, yet there is no effective treatment. In this study, a protein-bound pigment, allophycocyanin purified from blue-green algae is first reported to exhibit anti-enterovirus 71 activity. Allophycocyanin neutralized the enterovirus 71-induced cytopathic effect in both human rhabdomyosarcoma cells and African green monkey kidney cells. The 50% inhibitory concentration of allophycocyanin for neutralizing the enterovirus 71-induced cytopathic effect was approximately 0.045 ± 0.012 M in green monkey kidney cells. The cytotoxic concentrations of allophycocyanin for rhabdomyosarcoma cells and African green monkey kidney cells were 1.653 ± 0.003 M and 1.521 ± 0.012 M, respectively. A plaque reduction assay showed that the concentrations of allophycocyanin for reducing plaque formation by 50% were approximately 0.056 ± 0.007 M and 0.101 ± 0.032 M, when allophycocyanin were added at the state of viral adsorption and post-adsorption, respectively. Antiviral activity was more efficient in cultures treated with allophycocyanin before viral infection compared with that in the cultures treated after infection. Allophycocyanin was also able to delay viral RNA synthesis in the infected cells and to abate the apoptotic process in enterovirus 71-infected rhabdomyosarcoma cells with evidence of characteristic DNA fragmentation, decreasing membrane damage and declining cell sub-G1 phase. It is concluded that allophycocyanin possesses antiviral activity and has a potential for development as an anti-enterovirus 71 agent.

PUB: J. Med. Virol. 70:119-125, 2003.