Lomatia tinctoria (Moir and Thompson, 1973)

Deans, Bianca J., Tedone, Laura, Bissember, Alex C. & Smith, Jason A., 2018, Phytochemical profile of the rare, ancient clone Lomatia tasmanica and comparison to other endemic Tasmanian species L. tinctoria and L. polymorpha, Phytochemistry 153, pp. 74-78 : 75-76

2.3. Lomatia tinctoria

Maceration of L. tinctoria provided juglone (1) (0.58% w/w) and nonacosane (C 29 H 60) (0.13% w/w), as supported by 1 H NMR and GC-MS data (see: Supporting Information) ( Lytovchenko et al., 2009). GC-MS analysis of the crude diethyl ether extract also indicated the presence of heptacosane in small quantities (see: Supporting Information). The PHWE extract provided glucose as a mixture of α- and β- anomers. Juglone has been previously isolated from the seeds, wood and bark of L. tinctoria , however, the leaves were not investigated ( Moir and Thompson, 1973). Notably, juglone (1) was the only naphthoquinone pigment isolated from both L. tinctoria and L. polymorpha (vide supra). Moreover, lomatiol (2) was not isolated from either of these plants, despite previously being reported in the seeds of both species albeit only using qualitative methods ( Hooker, 1936).

These data indicate that, although all three species contained heptacosane and nonacosane, there are some differences in the chemical profiles of the respective leaf waxes associated with different species of Lomatia . Also, these non-polar molecules possibly reflect the epicuticular morphology of each species. L. tasmanica , which ostensibly features the thickest leaf epicuticular layer and provided the highest yields of non-polar components while L. polymorpha , which contains the thinnest surface coating, provided the lowest yields of these non-polar compounds.

2.4. Intraspecific variation of L. tasmanica , L. tinctoria and L. polymorpha

Intraspecific variation between all three species was also investigated. Three specimens from each species L. tasmanica (specimens A–C), L. tinctoria (specimens D–F), and L. polymorpha (specimens G–I) were collected from their respective populations. Each specimen was subject to the aforementioned two complementary extraction procedures. Analysis of the three individual specimens from the three respective species indicated consistency in phytochemical profiles within each of the species sampled (as judged by GC-MS, LC-MS and 1 H NMR spectroscopic analysis; see: Supporting Information). This tentatively suggests limited intraspecific variation within the respective endemic Tasmanian populations of each of species. Notably, analysis of the crude PHWE extracts of all leaf specimens (A–I) were consistent with the presence of both juglone (1) and its parent glycoside 6 as judged by LC–MS (see: Supporting Information). It is likely that because glycoside 6 is only present in trace amounts in both L. tasmanica and L. tinctoria it was not isolated via flash chromatography.