In vitro Evaluation of Anti-microbial Activities of Marine Streptomyces against Viral Models, Bacterial and Fungal Strains

Herpes simplex virus type 2 (HSV-2) is a dsDNA virus and it is the causative agent of genital herpes infection. The most important problem of herpes viruses is the reactivation that may lead to recurrent infection. On the other hand, Vesicular stomatitis virus (VSV) is a negative strand RNA virus that can cause many diseases to animals and rarely to human. Excess antiviral drugs use in the treatment of viral infections can induce mutagenicity and cross-resistance so searching for new source of antiviral drugs such as marine actinomycetes is required. A total of 72 Actinomycetes isolated from Qarun Lake governed to El-Fayoum-Egypt were screened for their antimicrobial activities against six bacterial strains, three fungal strains and one yeast strain. All of actinomycetes isolates were assayed for their antimicrobial activities using inhibition zone method and found that 10 isolates were active against bacteria, 3 isolates have activities against fungi and 5 isolates have both antibacterial and antifungal activities. All active isolates were tested for antiviral potentials using Cytopathic Effect (CPE) inhibition assay after determination of safe concentrations of actinomycete filtrates on Vero cells using MTT assay. Vesicular stomatitis virus (VSV) and Herpes simplex virus type 2 (HSV-2), were used as a test viruses. Nine isolates proved antiviral potentials against both viruses. Two isolates coded to Q3 and B2T were selected as the most active isolates against HSV-2 and VSV, respectively and were identified as a genus of Streptomyces. Our result gives conclusion that, marine actinomycetes still considered as a valuable source of many antimicrobial agents and can produce antiviral drugs against both DNA and RNA viruses.