Piper novae-hollandiae Miq. Leaf Extracts Lack Antibacterial activity and are Non-Toxic in vitro

Abstract

Introduction: Closely related plant species often share similar secondary metabolites and bioactivities and are therefore good targets for bioactivity testing when one or more species within a genus are known to possess therapeutic properties. The genus Piper has a long history of medicinal usage in many areas of the world. Many Piper spp. are known to have therapeutic properties and several have antibacterial bioactivities. Methods: The ability of P. novae-hollandiae leaf extracts to inhibit the growth of a panel of bacterial pathogens was investigated by disc diffusion assay. Toxicity was examined using the Artemia franciscana nauplii bioassay. Results: P. novae-hollandiae methanolic and aqueous extracts were completely ineffective at inhibiting the growth of panels of gram-positive and gram-negative bacteria. The extracts were nontoxic or of low toxicity to Artemia nauplii following 24 h exposure. Conclusion: Despite the close taxonomic relationship with several bioactive Piper spp. and its therapeutic use by first Australians, P. novae-hollandiae leaf extracts were completely ineffective bacterial growth inhibitors. However, these extracts may have other therapeutic properties and testing against protozoa, fungi, virus and tumour cells is warranted.

Insecticidal activity of the essential oil of Piper corcovadensis leaves and its major compound (1‐butyl‐3,4‐methylenedioxybenzene) against the maize weevil, Sitophilus zeamais

“…Among the alternatives are inert powders, such as diatomaceous earth, and products derived from plants, such as extracts, essential oils and lectins. [12][13][14][15][16][17][18] Extracts and essential oils from plants of the Piperaceae family are promising for pest and vector control. 19,20 The genus Piper is one of the most important members of this family, and essential oils from plants of this genus contain insecticidal compounds such as safrole.…”

“…Thus, insecticides that are safer and less‐aggressive for the environment have been investigated. Among the alternatives are inert powders, such as diatomaceous earth, and products derived from plants, such as extracts, essential oils and lectins 12–18 . Extracts and essential oils from plants of the Piperaceae family are promising for pest and vector control 19,20 .…”