The Activity of Plant-Derived Ren’s Oligopeptides-1 against the Pseudorabies Virus

SIMPLE SUMMARY: Although artificial antiviral drugs can effectively inhibit the proliferation of viruses, these drugs not only have serious side effects, but also create drug-resistant virus strains and produce harmful drug residues. In comparison, natural antiviral compounds have many distinctive advantages. For example, natural compounds, in general, have a lower toxicity, lower price, and better antiviral effects. Nowadays, wide applications of natural antiviral compounds not only provide us with safe meat products, but also reduce the abuse of antibiotics, thus reducing the number of drug-resilient microbes and viruses. The purpose of this study was to demonstrate the antiviral activity of Ren’s oligopeptides-1 against the pseudorabies virus (PRV). Ren’s oligopeptides-1 is a plant-derived drug with an antiviral activity against herpesvirus. Ren’s oligopeptides-1 contains ginger, garlic, onion, banana peel, and bitter melon. We discovered that the CC(50) value of Ren’s oligopeptides-1 was 15 mg/mL, while the EC(50) value was 6 mg/mL. This indicated that the concentration of 6 mg/mL was optimal for inhibiting the replication of PRV. In this study, PRV was used to conduct in vitro experiments on PK15 cells to explore the antiviral effect of Ren’s oligopeptides-1, which could become a promising feed additive. ABSTRACT: Newly synthesized Ren’s oligopeptides-1 was found to have an antiviral effect in clinical trials, and the purpose of this study was to further demonstrate the antiviral activity of Ren’s oligopeptides-1 against the PRV 152-GFP strain. We used the real-time cell analysis system (RTCA) to detect the cytotoxicity of different concentrations of Ren’s oligopeptides-1. We then applied high content screening (HCS) to detect the antiviral activity of Ren’s oligopeptides-1 against PRV. Meanwhile, the fluorescence signal of the virus was collected in real time and the expression levels of the related genes in the PK15 cells infected with PRV were detected using real-time PCR. At the mRNA level, we discovered that, at a concentration of 6 mg/mL, Ren’s oligopeptides-1 reduced the expression of pseudorabies virus (PRV) genes such as IE180, UL18, UL54, and UL21 at a concentration of 6 mg/mL. We then determined that Ren’s oligopeptides-1 has an EC(50) value of 6 mg/mL, and at this level, no cytotoxicity was observed.