The Anti-Viral Activity of Prunella vulgaris: A Narrative Review

Abstract

Introduction: This narrative review reports on the anti-viral activity of Prunella vulgaris with the aim of providing an overview of P. vulgaris research to date. P. vulgaris is an aromatic perennial herb that is common across diverse geographic regions. This article includes information about the investigation strategies and methodologies used to identify the nature of P. vulgaris’ s anti-viral mechanisms. Given its diverse interest and use, the P. vulgaris literature over the previous three decades reports on the phytochemical, agricultural, and pharmacological uses of the herb. To provide some background to the review, a brief description of the life cycle of the virus is given. Materials and Methods: The review was based on a literature search with three databases: Embase, Medline, and PubMed. The review’s inclusion criteria were unrestricted: The time of publication was unlimited; the keywords included ‘‘virus,’’ along with HIV and HSV (given the research’s historical focus), and ‘‘prunella vulgaris’’ (and variations). The articles identified were then categorized. Results: The search identified 24 articles, with 10 articles on human immunodeficiency virus (HIV), 8 articles on herpes simplex virus (HSV), and the remainder on other viruses. In vitro experimental designs dominated the methods, whereas in vivo parts were also noted. Most frequent P. vulgaris extraction methods included boiling for aqueous extract, followed by ethanolic extraction. Several anti-viral effective chemicals were identified across the studies, including polysaccharides, polyphenolics, triterpenes, and a range of essential oils. In this review, the articles were then categorized according to the stages of viral development and analysis methods, such as time-of-addition, pseudo-typing, and the use of reverse transcriptase, integrase, protease, and viral protein detecting kits. This categorization exposed the mechanisms behind the anti-viral influenza-like diseases, other than P. vulgaris, can be the candidates for further investigations. Volatile compounds from these herbs are also good targets, which may be proved to yield fruitful results.