Viola tricolor L.: A systematic review on ethnopharmacology, phytochemistry and pharmacology of an important traditional medicinal plant

Viola tricolor (Family: Violaceae) is a widely recognized plant known both for its medicinal value and its presence as a weed. The violet family consists of roughly 500 species across 20 genera, many of which are prevalent throughout diverse geographical regions. Viola tricolor blossoms in areas such as the Mediterranean, the Caucasus, and across continents including Europe, Asia, North and South America, and Australia. Traditionally, this plant has played a pivotal role in folk medicine, helping to treat conditions like bronchitis, asthma, respiratory inflammation, skin disorders, epilepsy, difficulty breathing, rheumatism, eczema, itching, and impetigo. It’s also known for aiding metabolism and offering calming, sedative effects. The plant is rich in bioactive compounds. Its key ingredients include flavonoids—especially rutin—as well as anthocyanins, coumarins, tannins, saponins, phenolic acids, cyclotides, mucilage, violantin, violaxanthin, violaquercetin, anthocyanidin glycosides, vitamin C (ascorbic acid), vitamin E (alpha-tocopherol), alkaloids, and essential oils. Both crude extracts and isolated substances from Viola tricolor exhibit a broad spectrum of pharmacological properties. These include antimicrobial, anti-inflammatory, antioxidant, diuretic, antitussive, immunosuppressive, and expectorant activities. This review draws upon literature issued between 2000 and 2025, sourced from reputable databases like Google Scholar, Sci-Hub, ResearchGate, and ScienceDirect. The paper provides a systematic overview of the plant’s botanical classification, global distribution, ethnomedicinal uses, chemical makeup, and therapeutic potential.