Inhibition of Zika Virus by Marine Algae

Abstract

For many years marine algae has been subject of numerous researches and as a source of natural products with antiviral activity, such as terpenes, alkaloids and sulphated polysaccharides. However, the anti-Zika virus (ZIKV) potential of algae has not been studied. In this study we evaluated extracts seven species of the three major classes of seaweeds (Phaeophyceae, Chlorophyceae and Rhodophyceae) against ZIKV. All seaweeds tested are native of the Brazilian coast, except for Kappaphycus alvarezii that can be cultivated. ZIKV a mosquito-borne flavivirus, has become a public health problem. In recent years there has been an increase in the number of cases and a strong association between ZIKV outbreak and the spread of cases of Guillain-Barré Syndrome and microcephaly. All seaweed extracts tested in this work inhibits ZIKV replication in a dose-dependent manner. Caulerpa racemosa, Kappaphycus alvarezii and Osmundaria obtusiloba extracts were able to inhibit viral replication at low concentrations with EC50 values ranging from 1.38 to 1.98 µg/mL. We observed that O. obtusiloba presented a significant virucidal effect. Our results suggest that extracts of C. racemosa, K. alvarezii and O. obtusiloba presented very promising results, being excellent candidates for further studies, demonstrating that marine algae are an interesting source for the development of novel anti-ZIKV agents.

Bioactive Compounds, Cosmeceutical And Nutraceutical Applications of Green Seaweed Species (Chlorophyta)

“…A study was conducted on the antiviral treatment of Zika virus (ZIKV), which presented the inhibition of C. racemosa towards ZIKV replication in a dose-dependent manner. The study found that C. racemosa extract exhibited the highest cytotoxicity (CC 50 ) effect, 732 µg/mL against ZIKV (Cirne-santos et al, 2017). It can be said that Chlorophyta extracts can be a promising species for further studies for the development of new antiviral agents.…”

Antiviral Effect of Caulerpin Against Chikungunya

“…We have already published a paper, which demonstrates that the algae extract of C. racemosa presents a 732 mg/mL CC 50 . 26…”

“…The search for drugs that act at different stages of viral replication in addition to its low toxicity may be important to determine if it is possible to adopt it for clinical use. 26 In this way, when we observed the low cytotoxicity and high inhibition of the replication of CHIKV, we evaluated the inhibitory effect of the compound added at different times after viral infection. We observed that caulerpin added in time 0, 1, 2, and 3 hours postinfection still maintains an inhibitory potential of viral replication 100% for CHIKV.…”

“…We have already published a paper, which demonstrates that the algae extract of C. racemosa presents a 732 mg/mL CC 50 . 26 After the outbreaks of infection and its accelerated spread caused by CHIKV 27 as well as their strong impacts on public health, severe associations with signs and symptoms of high severity possibly caused by these viruses. Several studies have been carried out in the search of compounds that can act on viral replication reducing the severity of the cases and improving the quality of life of the affected people.…”

Acute toxicity evaluation of ethanol extract of red algae, Osmundaria obtusiloba, in BALB/c mice

“…Norris species is characterized as a robust plant (Rhodophyta, Ceramiales, Rhodomelaceae), which can measure from 10 to 15 cm in height, with flat apices of 3 to 4 mm wide, showing dark red coloration (Carvalho et al, 2006). Several biological activities have been described from O. obtusiloba, mainly for their extracts, such as the fraction of O. obtusiloba rich in lectin that inhibited the trypsin and α-amylase enzymes, indicating its potential use in the production of drugs against diabetes (de Oliveira et al, 2009) or the ethanol extract that was able to inhibit the replication of Zika virus while maintaining low cytotoxicity (CC 50 =525 µg/ml) (Cirne-Santos et al, 2017). Antiviral activity against HSV-1 and HSV-2 has also been described for glycolipids extracted from O. obtusiloba (de Souza et al, 2012).…”