Bioactivity and chemical characterisation of Lophostemon suaveolens – an endemic Australian Aboriginal traditional medicinal plant

Abstract

Lophostemon suaveolens is a relatively unexplored endemic medicinal plant of Australia. Extracts of fresh leaves of L. suaveolens obtained from sequential extraction with n-hexane and dichloromethane exhibited antibacterial activity in the disc diffusion and MTT microdilution assays against Streptococcus pyogenes and methicillin sensitive and resistant strains of Staphylococcus aureus (minimum bactericidal concentration < 63 μg/mL). The dichloromethane extract and chromatographic fractions therein inhibited nitric oxide in RAW264.7 murine macrophages (IC50 3.7-11.6 μg/mL) and also PGE2 in 3T3 murine fibroblasts (IC50 2.8-19.7 μg/mL). The crude n-hexane, dichloromethane and water extracts of the leaves and chromatographic fractions from the dichloromethane extract also showed modest antioxidant activity in the ORAC assay. GC-MS analysis of the n-hexane fraction showed the presence of the antibacterial compounds aromadendrene, spathulenol, β-caryophyllene, α-humulene and α-pinene and the anti-inflammatory compounds β-caryophyllene and spathulenol. Fractionation of the dichloromethane extract led to the isolation of eucalyptin and the known anti-inflammatory compound betulinic acid.

Phytochemical Profile and Antibacterial and Antioxidant Activities of Medicinal Plants Used by Aboriginal People of New South Wales, Australia

“…As part of a collaborative research program initiated upon the request of Yaegl Aboriginal people of Northern New South Wales (NSW) to help with conserving, analysing, and developing their medicinal knowledge for ecotourism and healthcare, we have ethnobotanically documented thirty-two Yaegl medicinal plants [ 10 ] and conducted preliminary biological and phytochemical studies [ 11 , 12 ]. To extend this research program, we conducted a literature review in 2012 of 128 plants used as traditional medicines across NSW with regard to their distribution and habitat, documented traditional use, biological activity, and phytochemistry [ 3 ].…”

Anti-mycobacterial and immunomodulatory activity of n-hexane fraction and spathulenol from Ocotea notata leaves

“…In addition, a spathulenol analogous is one of the major constituents of SF4, and the antibacterial potential of aromadendrane-type sesquiterpenes has been partially investigated in the literature. Aromadendrane-type sesquiterpenes showed antibacterial activity against Streptococcus pyogenes methicillin, as well as sensitive and resistant strains of Staphylococcus aureus (Naz et al 2015). Furthermore, viridiflorol, one (Trevizan et al 2016).…”

Macquarie–Yaegl Partnership: Community Capability Strengthening Through Western and Indigenous Science

“…This research provided the first comprehensive study of Yaegl medicinal plants, leading to the conservation of knowledge of 54 medicinal plant preparations and the understanding of biological properties and bioactive compounds aligned with the customary uses of these previously underexplored plants. [12,[19][20][21] With the Yaegl Elders and the Macquarie research team (IBRG), we have so far coauthored five refereed scientific papers on the Yaegl medicinal plants. [12,[19][20][21][22] This research is ongoing, in partnership with the Elders.…”

“…[12,[19][20][21] With the Yaegl Elders and the Macquarie research team (IBRG), we have so far coauthored five refereed scientific papers on the Yaegl medicinal plants. [12,[19][20][21][22] This research is ongoing, in partnership with the Elders. The research work with the Yaegl Elders has been showcased in the ABC Message Stick Caring for Country series and Catalyst, on ABC Radio National Drive, and in the national newspaper, The Australian, amongst other media.…”