The genus Eremophila (Scrophulariaceae): an ethnobotanical, biological and phytochemical review

Abstract

Objectives Eremophila (Scrophulariaceae) is an endemic Australian genus with 214 species, which is commonly known as Fuchsia bush, Emu bush or Poverty bush. Plants of this genus played an important role for the Australian Aborigines who used them widely for medicinal and ceremonial purposes. Many studies have been carried out on many species of this genus and have generated immense data about the chemical composition and corresponding biological activity of extracts and isolated secondary metabolites. Key findings Thorough phytochemical investigations of different Eremophila species have resulted in the isolation of more than 200 secondary metabolites of different classes with diterpenes as major constituents. Biological studies and traditional clinical practice demonstrated that Eremophila and its bioactive compounds possess various pharmacological properties. Plants were employed especially as a cardiotonic drug and also as potent anti-inflammatory, antimicrobial and antiviral agents. Summary Further investigations are required to explore other Eremophila species, to evaluate the different biological activities of either their extracts or the isolated compounds and the possible underlying modes of action.

Nerylneryl diphosphate is the precursor of serrulatane, viscidane and cembrane-type diterpenoids in Eremophila species

“…Eremophila species are a rich source of novel terpenoids, particularly diterpenoids [22]. Early studies have suggested that in many Eremophila species diterpenoids are biosynthesised in glandular trichomes from where they are released to form part of the viscid resins that coat the surface of leaves [53,[65][66][67].…”

“…The diterpenoid chemistry of Eremophila is diverse with over 100 different structures reported to-date [12,15,[17][18][19]22]. Linear, macrocyclic, and polycyclic structures are represented across the genus, but no labdane-related diterpenoids (which are often the predominant class found in plants [23]) have been reported.…”

Antihyperglycaemic activity of the methanol extract from leaves of Eremophila maculata (Scrophulariaceae) in streptozotocin-induced diabetic rats

“…Plants of this genus have traditionally been used to treat conditions of the gastrointestinal tract, respiratory and skin lesions. Laboratory investigations provided evidence that plants of the genus Eremophila exhibit antidiabetic, antimicrobial, anti‐inflammatory, immunomodulatory and antiproliferative properties . Plants of this genus produce many biologically active secondary metabolites belonging to various classes, mainly flavonoids, lignans, phenylpropanoids and terpenoids …”

Plant‐derived medicinal entomochemicals: an integrated approach to biodiscovery in Australia

“…microtheca † Witchetty grubs (M, F); Lerps (Psyllidae) (F); Galls (Eriococcidae) (F) (Deegan et al 2010;Latz 2018) Colds, flu, internal pains, joint pain, skin sores, pruritus, headache (L, B); toothache, medicinal wash (B) (ACNT 1993;Peile and Bindon 1997;Bordulk et al 2012) Antibacterial, antifungal, antioxidant, insecticidal (L) (Ghaffar et al 2015;Maghsoodlou et al 2015;Nikbakht et al 2015;Siddique et al 2017Siddique et al , 2018 Saponins (B); terpenoid essential oils (e.g. 1,8cineole and α-pinene) (L, F) (ACNT 1993;Bignell et al 1997;Ghaffar et al 2015;Maghsoodlou et al 2015;Nikbakht et al 2015;Siddique et al 2017Siddique et al , 2018 Eucalyptus intertexta (Floater 1996;Walsh et al 2014) Sores, burns, cuts (G) (Bindon 1996) Antitumour activity (L, St) (Collins et al 1990 (ACNT 1993;Bindon 1996;Latz 2018) Antimicrobial, antioxidant (L, Sm, St); modulation of platelet activity (antiheadache) (L, F); cardioactive effects (L) (Pennacchio et al 1996;Rogers et al 2000;Hayhoe and Palombo 2011;Sadgrove et al 2011;Singab et al 2013; Terpenoid essential oils, iridoid glucoside (geniposidic acid), alkaloids, phenylpropanoids (L); genifuranal (Sm); phenolics (St) (Pennacchio et al 1996;Sadgrove et al 2011;Singab et al 2013; References are provided within each subheading. Note: the terms 'witchetty/edible grubs', 'lerp' and so forth may constitute many different species.…”