Ulvan for COVID-19

Marine algal extracts exhibit a potent inhibitory effect against several enveloped and non-enveloped viruses. The infection of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) has several adverse effects, including an increased mortality rate. The anti-COVID-19 agents are still limited; this issue requires exploring novel, effective anti-SARS-CoV-2 therapeutic approaches. This study investigated the antiviral activity of an aqueous extract of Ulva lactuca, which was collected from the Gulf of Suez, Egypt. The aqueous extract of Ulva lactuca was characterized by high-performance liquid chromatography (HPLC), Fourier-transform infrared spectroscopy (FTIR), X-ray diffraction (XRD), and Energy Dispersive X-ray (EDX) analyses. According to the HPLC analysis, the extract comprises several sugars, mostly rhamnose (32.88%). The FTIR spectra showed numerous bands related to the functional groups. EDX analysis confirmed the presence of different elements, such as oxygen (O), carbon (C), sulfur (S), magnesium (Mg), potassium (K), calcium (Ca), and sodium (Na), with different concentrations. The aqueous extract of U. lactuca (0.0312 mg/mL) exhibited potent anti-SARS-CoV-2 activity via virucidal activity, inhibition of viral replication, and interference with viral adsorption (% inhibitions of 64%, 33.3%, and 31.1%, respectively). Consequently, ulvan could be a promising compound for preclinical study in the drug development process to combat SARS-CoV-2.

Lately there has been a lot of interest worldwide in studies on the antiviral activities of marine natural secondary metabolites, notably marine polysaccharides. It has been established that polysaccharides made from marine sources and their derivatives have antiviral effects against potent viruses. Agricultural, biological, food, and pharmaceutical industries all make extensive use of goods obtained from algae. The most well-known chemical components found in algae are polysaccharides, which have been the subject of a variety of studies because of their varied bioactivities. Polysaccharides made from algae have recently risen to the top of pharmaceutical research due to their fascinating antiviral potential. Currently, COVID-19 can be prevented with vaccination, but the brown alga Sargassum wightii has several bioactive compounds that have the following qualities and may be a better option. S. wightii is one of the marine algae species that is rich in sulfated polysaccharides, the secondary metabolites which have antiviral action and the capacity to prevent viral proliferation. Fucoidan, a long-chain sulfated polysaccharide found in various brown algae, has potent antiviral effects. Additionally, sulfated polysaccharides from green algae (such as ulvans) and red algae (such as carrageenan), and lectins from red algae (such as griffithsin) have antiviral therapeutic agents against coronaviruses and other viruses. This research focuses on screening seaweeds for possible antiviral compounds to treat viral infections notably COVID-19.