identifier	taxonID	type	CVterm	format	language	title	description	additionalInformationURL	UsageTerms	rights	Owner	contributor	creator	bibliographicCitation
233B3318FFFE0265FFC0FF7160B7AF04.text	233B3318FFFE0265FFC0FF7160B7AF04.taxon	http://purl.org/dc/dcmitype/Text	http://rs.tdwg.org/ontology/voc/SPMInfoItems#GeneralDescription	text/html	en	Lepidosperma viscidum R. Br.	<html xmlns:mods="http://www.loc.gov/mods/v3">
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            <p> 2.3. F type propolis and its botanical source from  L. viscidum</p>
            <p> A plant source foraged by honey bees to produce propolis on Kangaroo Island was found to be the resinous exudate of  Lepidosperma sp. Montebello (Duke et al., 2017). The resinous exudates from other species of  Lepidosperma genus collected on KI and south-east South Australia were compared by TLC and 1 H NMR analysis with propolis samples. A close match was found for both TLC (Supplementary data, Fig. 3S) and 1 H NMR spectra profiles (Fig. 5) between resin from  L. viscidum (Fig. 4S) and propolis samples rich in 1 H NMR signals characteristic of flavanones, designated as F type propolis. F type propolis is relatively uncommon on KI (18 out of 2602 samples) and relatively common in south-east South Australia (4 out of 11 samples). This frequency of appearance is consistent with the uncommon occurrence of  L. viscidum on KI and its common occurrence in the areas in South Australia from where F-type propolis samples were collected.  L. viscidum resinous leaf and leaf base ethanol extract from Seal Bay, KI, was fractionated by normal-phase short column vacuum chromatography and fractions of sufficient purity were characterised by 1 H and 13 C NMR spectra and mass spectrometry resulting in the identification of five compounds 4, 5, 8, 9 and 10. </p>
            <p> Chemistry of  L. viscidum resin is markedly different from that previously observed in another propolis resin sourced from  Lepidosperma genus on Kangaroo Island (Duke et al., 2017; Abu-Mellal et al., 2012). This propolis type has resin sourced from  Lepidosperma sp. Montebello, with chemistry extensively investigated (Duke et al., 2017; Abu-Mellal et al., 2012). The compounds isolated from resins of that species are predominantly C- and O-prenylated hydroxystilbenes or derivatives thereof, many with piceatannol as base structure. By comparison,  L. viscidum resin appears to be predominantly 6- or 8-methyl or dimethyl polyhydroxyflavanones 8, 9 and 10 (Fig. 6); 1 H NMR spectra of less pure fractions also suggests the presence of some O-methylated flavanones. Notably, prenylation appears to be less common in  L. viscidum resin compounds, with the exception of the two dihydrochalcones, 4 and 5, isolated. </p>
            <p> Compounds similar to 4 and 5 without the 4-hydroxyprenyl substituent, 4,2 ′,4 ′ -trihydroxydihydrochalcone (davidigenin) (Jensen et al., 1977) and 4,2 ′ -dihydroxy-4 ′ -methoxydihydrochalcone (Kostrzewa-Susłow and Janeczko, 2012) have 1 H and 13 C NMR spectral results that show good partial concordance with 4 and 5. The most similar structure to 5 reported was 3 ′ -prenyl-4,2 ′ -dihydroxy-4 ′ -methoxydihydrochalcone (Awouafack et al., 2010). The stereoisomer identified in 4 and 5 was the E configuration. This configuration is reported to be predominant in terminally-hydroxylated prenyl groups in natural products (Erasto et al., 2004; Nguyen et al., 2012). Compounds 4 and 5 are previously undescribed: a number of 3 ′ -prenyl hydroxydihydrochalcones have been reported from natural sources but no 5 ′ -prenylated structures to date. These 3 ′ -prenyl hydroxydihydrochalcones have been isolated from genera  Angelica (Apiaceae) (Luo et al., 2012a),  Artocarpus (Moraceae) (Jamil et al., 2008),  Bacopa (Plantaginaceae) (Suresh et al., 2010),  Broussonetia (Moraceae) (Luo et al., 2012b),  Eriosema (Fabaceae) (Awouafack et al., 2008, 2010) and  Lonchocarpus (Fabaceae) (Borges-Arg´aez et al., 2009), none of these genera being closely related to the  Cyperaceae . Limited information on biological activity of these compounds exists, but one is a reported strong free radical scavenger by the DPPH assay (Jamil et al., 2008) and another has been observed to inhibit aromatase (Luo et al., 2012b). </p>
            <p> The molecular weight of compounds identified as 5,7,4 ′ -trihydroxy- 6,8-dimethylflavanone (farrerol) (8), 5,7,3 ′,5 ′ -tetrahydroxy-6,8-dimethylflavanone (9) and 5,7,3 ′,5 ′ -tetrahydroxy-6-methylflavanone (10) was determined by mass spectrometry. Close matches with literature 13 C NMR and 1 H NMR spectra enabled identification of the structures of these known compounds: farrelol (8) (Lai et al., 2016); 9 (Lou et al., 2015); 10 (Yi et al., 2002; Zhang et al., 2018). Farrerol (8) has a long history in the literature and has been isolated from plants from a widespread number of genera (Lai et al., 2016). Compound 9 has previously been isolated from  Rhododendron dauricum (Ericaceae) (Wang et al., 2015) as per farrerol, and 10 from the conifer  Pseudotsuga sinensis (Pinaceae) (Yi et al., 2002; Zhang et al., 2018). Neither species belong to families closely related to the  Cyperaceae . No reports of biological activity for these compounds were found (Wang et al., 2015; Yi et al., 2002; Zhang et al., 2018). F type propolis and its resin source  L. viscidum are a promising source of a diverse range of flavanones of potentially useful biological activity, and of farrerol, a compound of intense pharmaceutical interest (Dai et al., 2016) and long-term traditional use (Chen et al., 2009). </p>
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	https://treatment.plazi.org/id/233B3318FFFE0265FFC0FF7160B7AF04	Public Domain	No known copyright restrictions apply. See Agosti, D., Egloff, W., 2009. Taxonomic information exchange and copyright: the Plazi approach. BMC Research Notes 2009, 2:53 for further explanation.		Plazi	King, Douglas I.;Hamid, Kaiser;Tran, Van H.;Duke, Rujee K.;Duke, Colin C.	King, Douglas I., Hamid, Kaiser, Tran, Van H., Duke, Rujee K., Duke, Colin C. (2021): Kangaroo Island propolis types originating from two Lepidosperma species and Dodonaea humilis. Phytochemistry (112800) 188: 1-11, DOI: 10.1016/j.phytochem.2021.112800, URL: http://dx.doi.org/10.1016/j.phytochem.2021.112800
