History of Viruses
Human beings have been battling viruses since before Homo Sapiens evolved into modern form. For some viruses, vaccines and antiviral drugs have allowed us to keep infections from spreading widely and have helped sick people recover. For one disease —smallpox—we’ve been able to eradicate it, ridding the world of new cases. But as new viruses demonstrate, we are a long way from winning the battle against viruses.
No one knows exactly when viruses emerged or from where they came since viruses do not leave historical footprints such as fossils. Modern viruses are thought to be a mosaic of bits and pieces of nucleic acids picked up from various sources along their respective evolutionary paths. Viruses are acellular, parasitic entities that are not classified within any kingdom. Unlike most living organisms, viruses are not cells and cannot divide. Instead, they infect a host cell and use the host’s replication processes to produce identical progeny virus particles. Viruses infect organisms as diverse as bacteria, plants, and animals. They exist in a netherworld between a living organism and a nonliving entity. Living things grow, metabolize, and reproduce. Viruses replicate, but to do so, they are entirely dependent on their host cells. They do not metabolize or grow but are assembled in their mature form.1, 2
Discovery And Detection
Viruses were first discovered after the development of a porcelain filter, called the Chamberland-Pasteur filter, which could remove all bacteria visible in the microscope from any liquid sample. In 1886, Adolph Meyer demonstrated that a disease of tobacco plants, tobacco mosaic disease, could be transferred from a diseased plant to a healthy one via liquid plant extracts. In 1892, Dmitri Ivanowski showed that this disease could be transmitted in this way even after the Chamberland-Pasteur filter had removed all viable bacteria from the extract. Still, it was many years before it was proven that these “filterable” infectious agents were not simply very small bacteria but were a new type of very small, disease-causing particle.1, 2
Virions, single virus particles, are very small, about 20–250 nanometers in diameter. These individual virus particles are the infectious form of a virus outside the host cell. Unlike bacteria (which are about 100 times larger), we cannot see viruses with a light microscope, with the exception of some large virions of the poxvirus family.1, 2
Distinctive structure of viruses and their complicated life cycle have made the discovery of definite treatments against viral infections extremely demanding. Despite comprehensive studies for suitable vaccines and treatments against viral infections over the past half of a century, several infections still afflict a substantial proportion of the world populations in all generations.3, 4, 5 Vaccine development against some viruses has so far proved to be an intractable approach, and there is no definite vaccine against numerous prevalent viral infections, including most respiratory-tract viruses, herpes viruses, and human papilloma viruses. Moreover, drug resistance to available antiviral agents by different viruses has always been a serious impediment to the treatment of viral infections.6 Until the 21st century, approximately less than only ten drugs were officially licensed against viral infections. Since then, a better understanding of the viral proliferation cycle and numerous researches have marked a quantum leap forward in the discovery of new antiviral drugs.7 Nonetheless, despite some very real gains, we are still far more away from controlling viral infections. Especially since, respiratory viruses can spread rapidly and are spread directly by droplets coughed or sneezed into the air which are then inhaled, or indirectly by contaminated hands, handkerchiefs, toys, etc. which come in contact with the mucosal membranes found in your mouth, nose or eyes.
Potential Polysaccharide Sea Solutions
The unique living environment has gifted the marine world an assorted collection of algae from microorganisms to giant seaweeds. Amongst marine natural products, approximately 9% of biomedical compounds have been isolated from algae.8 These marine organisms can synthetize assorted types of metabolisms, including polysaccharides, chlorophyll, acetogenins, fatty acids, vitamins, xanthophylls, amino acids, and halogenated compounds.9, 10, 11, 12, Despite being underexploited plant resources, recent investigations have established algae as a rich arsenal of active metabolites with pharmaceutical potential, including anticancer, antitumor, antioxidant, antiobesity, neuroprotective, antimicrobial, antinociceptive, anti-inflammatory, antiangiogenic activities9, 13, 14, 15, 16, 17 and antiviral properties.18
A study by Gerber and colleagues in 1958 showed inhibition of mumps and influenza B virus by polysaccharides from marine algae and has introduced algae-derived polysaccharides as a potent source of antiviral agents.18 Subsequently, antiviral activities of other polysaccharide fractions isolated from red algae were reported against HSV and other viruses in the following two decades. Since then, numerous studies have published antiviral potential of various algae-derived polysaccharides and their underlying mechanism of action.19 This review tries to summarize the antiviral activities of algae-derived polysaccharides and the mechanisms underlying these activities.
Marine life is a veritable treasure trove of natural medicine, and red marine algae is no exception: the ocean-growing macro-algae is in fact commonly touted as a ‘therapeutic food.’ A sea vegetable that is part of the Rhodophyta class, it has been a staple in the diets of Eastern civilizations for thousands of years.
(Gigartina Skottsbergii) extract, a sea algae extract (SAE) is a sulfated polysaccharide with the high molecular weight isolated from marine red alga Schizymenia Pacifica. SAE is a member of carrageenan, which is composed of galactose (73%), sulfonate (20%), and 3,6-anhydrogalactose (0.65%), and it is known that SEA is a selective viral inhibitor.20
Carrageenans or carrageenins (karr-ə-gee-nənz, from Irish carraigín, “little rock”) are a family of linear sulfated polysaccharides that are extracted from red edible seaweeds.21
Human clinical trials recorded in the National Institutes of Health database indicate the sulfated polysaccharides in gigartina may help counter oral and genital herpes, shingles, HIV, influenza, and other viruses. Regular intake may reduce the number of viral attacks and their severity.22
Gigartina is a plentiful source of protein, vitamins, trace minerals, and fiber. Many species of marine algae including, gigartina contain significant quantities of complex structural sulfated polysaccharides that have been shown to inhibit the replication of enveloped viruses, including members of the flavivirus.23 The gigartina strain of red marine algae is the richest known source of sulfated polysaccharides.
Of the 4,000 or so species of red marine algae, only 25 contain a significant number of sulfated polysaccharides. More importantly, there are only a few of these 25 strains that have antiviral properties backed by extensive research.
Red marine algae is also high in antioxidants, which help to power up our immune systems to combat free radical damage. Although red marine algae, in its dried form, is a popular snack throughout Asia, it is perhaps better known—at least to Westerners—for its medicinal properties. In this regard, it is similar to other popular algae such as spirulina and chlorella. Although its effects are very different: the blue-green algae are best-known as heavy metal detoxifiers. Like many other marine organisms, red marine algae appears to have significant medicinal properties in the form of bioactive compounds—hence its use in Chinese medicine since ancient times.
The antiviral compounds of red marine algae are particularly noteworthy. The carrageenans in red marine algae, for instance, are thought to ramp up interferon production in the immune system. Interferons are proteins dispatched by cells to meet the advance of intruding viruses, inhibiting the ability of the said virus to replicate and cause damage.1 Carrageenans also increase the productivity of T and B-cells which destroy cells already infected with a virus. Because of this, red marine algae is considered by some to be a powerful preventative measure against everything from yeast infections and shingles to serious viruses like HPV and Epstein-Barr.
Given that the human body can develop resistance to specific antiviral drugs prescribed by a doctor, many people suffering from HPV, HSV, and other viruses have experimented with red marine algae—an entirely natural product.
As well as evidence in the form of testimonies from many sufferers of such conditions, there have been several scientific trials conducted assessing the algae’s protective effects. Typically present in both red and purple sea algae, carrageenan consists of numerous polysaccharides, carbohydrates whose molecules comprise bonded sugar molecules. One group of these, sulfated polysaccharides, is a particular group to which we can credit many of RMA’s most appreciable benefits.
Sulfated polysaccharides (“poly” meaning many and “saccharide” meaning sugar) are complex sugars that contain sulfur. Carrageenan and other gel-like substances are members of this family of polysaccharides. Research has isolated and identified several sulfated polysaccharides from sea plants that improve immune function, especially during harsh winter months. Plant sterols found naturally in the red marine algae may provide additional immune-boosting benefits.
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