Study of the antiviral activity of bioactive peptides extracted from black sea cucumber (Holothuria leucospilota) against Herpes simplex (types 1 and 2), Chikungunya, and Dengue viruses

Given the concerns regarding the use of synthetic antiviral compounds in the pharmaceutical industry, it seems necessary to pay attention to natural sources with antiviral activity. Sea cucumbers are one of these sources that numerous physiological properties are discussed in the scientific community. The present study aimed to produce bioactive peptides from Holothuria leucospilota using two microbial enzymes, alcalase and flavourzyme, and to evaluate their antiviral activity against Herpes simplex types 1 and 2, Chikungunya, and Dengue viruses. The results showed that the whole body of the sea cucumber has about 13% protein, which this amount reached more than 67% in the resulting hydrolyzed powders. The amount of protein, as well as the degree of hydrolysis in the hydrolyzed protein using alcalase enzyme (71.58±0.16 and 48.37±0.3%, respectively) was higher than the powder produced with flavourzyme (67.88±0.26 and 41.42±0.6%, respectively) (p<0.05). It was further found that both types of peptides produced at both concentrations of 4 and 5 mg/ml have antiviral properties. In this study, the type of enzyme used to produce bioactive peptides and also the concentration of peptides had a significant effect on their antiviral activity (p<0.05). The peptides produced using alcalase enzyme had significantly more antiviral activity against the studied viruses, while increasing the concentration of peptides from 4 to 5 mg/ml led to a significant increase in the antiviral activity (p<0.05). Among the studied viruses, Herpes type 1 and Dengue virus were the most resistant and susceptible viruses, respectively (p<0.05). According to the results of the present study, bioactive peptides extracted from the sea cucumber have the potential to be used in the pharmaceutical industry as a natural antiviral compound, however, it is necessary to carry out additional tests to evaluate their possible toxicity effects.