Botany, uses, phytochemistry and pharmacology of Vallaris: A short review

Abstract

The World Checklist of Selected Plant Families has listed a global list of 28 species for Vallaris under the family Apocynaceae of which only Vallaris glabra, Vallaris solanacea and Vallaris indecora are accepted names. In this short review, the current knowledge of the botany, uses, phytochemistry and pharmacology of V. glabra and V. solanacea is reviewed as there is no information on the chemical constituents and bioactivities of V. indecora. V. glabra (L.) Kuntze or bread flower is a woody climber with broadly elliptic leaves. Flowers are cup-like and white with a unique fragrance of leaves of pandan or newly cooked fragrant rice. The species is a popular ornamental plant in gardens of Southeast Asia. No uses of V. glabra in traditional medicine have been reported. From the leaves of V. glabra, cardiac glycosides, phenolic acids, fatty acids and triterpenes have been isolated. Essential oils extracted from flowers have been identified. The antiproliferative, antiplasmodial and antioxidant properties of V. glabra are reviewed. V. solanacea (Roth) Kuntze is a twining shrub up to 10 m tall. Leaves are elliptic and densely pubescent on both surfaces. Flowers are white or creamy, fragrant and borne in clusters. The species occurs naturally in forests of South and Southeast Asia. Traditionally, the milky latex of V. solanacea can be applied to treat ringworm and other skin infections, including sores, cuts and wounds. From leaves and seeds of V. solanacea, cardiac glycosides, fatty acids and triterpenes have been isolated. From the root bark, essential oils have been identified. Leaves and barks of V. solanacea have been reported to possess anticancer, antimicrobial, analgesic, anti-inflammatory, anti-diarrhoeal and cardiotonic properties, and display toxicity to brine shrimp but not to rats. V. indecora (Baill.) Tsiang & P.T. Li is a trailing shrub with elliptic or obovate leaves and pale yellow flowers. Occurring in China, the plant is used to treat worm diseases.