Tasmannia lanceolata (Poir.) A.C. Sm. and Tasmannia insipida R.Br. ex. DC. Extracts Inhibit the Growth of Axillary and Foot Odour Producing Bacteria

Introduction: Tasmannia spp. extracts inhibit the growth of many bacterial pathogens. They may also inhibit the growth of malodour producing bacteria and thus be useful deodorant components, although this is yet to be tested. Methods: T. lanceolata and T. insipida fruit and leaf solvent extracts were investigated by disc diffusion and liquid dilution MIC assays against the most significant bacterial contributors to axillary and plantar malodour formation. Toxicity was determined using the Artemia franciscana nauplii bioassay. Non-targeted HPLC separation of the T. lanceolata methanolic berry extracts, coupled to high resolution time- of-flight (TOF) mass spectroscopy was used for the identification and characterisation of individual components in the extract. Results: The methanolic and aqueous T. lanceolata and T. insipida fruit and leaf extracts displayed noteworthy bacterial growth inhibitory activity against all of the malodour forming bacteria tested. The T. lanceolata methanolic fruit extract was particularly potent, with low MIC values recorded against C. jeikeium (480µg/mL) and S. epidermidis (513µg/mL), as well as moderate activity against P. acnes (1750µg/mL) and B. linens (1250µg/mL). Similar MIC values were noted for the aqueous T. lanceolata fruit extract against C. jeikeium and S. epidermidis, although this extract was ineffective against the other bacteria tested. Similar, albeit less potent inhibitory profiles were noted for the T. lanceolata and T. insipida leaf extracts against C. jeikeium and S. epidermidis. All Tasmannia spp. extracts were nontoxic in the Artemia fransiscana bioassay. Non-biased phytochemical analysis of the methanolic leaf extract highlighted several notable compounds, including polygodial, capsidiol, salutarisolide gallic acid and combretastatin A1 in relative abundance. Conclusion: The lack of toxicity of the T. lanceolata and T. insipida fruit and leaf extracts and their potent growth inhibition of axillary and plantar malodour producing bacteria indicate their potential as deodorant components.