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Aim We examine the range expansion/contraction dynamics during the last glacial cycle of the late-successional tropical rain forest conifer Podocarpus elatus using a combination of modelling and molecular marker analyses. Specifically, we test whether distributional changes predicted by environmental niche modelling are in agreement with (1) the glacial maximum contractions inferred from the southern fossil record, and (2) population genetic-based estimates of range disjunctions and demographic dynamics. In addition, we test whether northern and southern ranges are likely to have experienced similar expansion/contraction dynamics. Location Eastern Australian tropical and subtropical rain forests. Methods Environmental niche modelling was completed for three time periods during the last glacial cycle and was interpreted in light of the known palynology. We collected 109 samples from 32 populations across the entire range of P. elatus. Six microsatellite loci and Bayesian coalescence analysis were used to infer population expansion/contraction dynamics, and five sequenced loci (one plastid and four nuclear) were used to quantify genetic structure/diversity. Results Environmental niche modelling suggested that the northern and southern ranges of P. elatus experienced different expansion/contraction dynamics. In the northern range, the habitat suitable for P. elatus persisted in a small refugial area during the Last Glacial Maximum (LGM, 21 ka) and then expanded during the post-glacial period. Conversely, in the south suitable habitat was widespread during the LGM but subsequently contracted. These differential dynamics were supported by Bayesian analyses of the population genetic data (northern dispersal) and are consistent with the greater genetic diversity in the south compared with the north. A contact zone between the two genetically divergent groups (corresponding to the Macleay Overlap Zone) was supported by environmental niche modelling and molecular analyses. Main conclusions The climatic fluctuations of the Quaternary have differentially impacted the northern and southern ranges of a broadly distributed rain forest tree in Australia. Recurrent contraction/expansion cycles contributed to the genetic distinction between northern and southern distributions of P. elatus. By combining molecular and environmental niche modelling evidence, this unique study undermines the general assumption that broadly distributed species respond in a uniform way to climate change.

Purified polyphenolic-rich extracts from four native Australian fruits, Illawarra Plum ( Podocarpus elatus Endl., Podocarpaceae ), Kakadu Plum ( Terminalia ferdinandiana Exell, Combretaceae ), Muntries ( Kunzea pomifera F. Muell., Myrtaceae ) and Native Currant ( Acrotriche depressa R.Br., Epacridaceae ), were screened for their ability to modulate anti-inflammatory activity in LPS-activated murine macrophages (RAW 264.7). The Kakadu Plum extract inhibited the expression of inducible nitric oxide synthase (iNOS), and importantly was the only fruit in this study that displayed differential inhibition of the expression of cyclooxygenase (COX)-2 but not COX-1. Illawarra Plum (COX-2 and iNOS) and Native Currant (iNOS only) also inhibited inflammatory enzymes, while Muntries exhibited none of these activities under the same conditions. All evaluated extracts inhibited the production of prostaglandin E 2 and nitric oxide, suggesting the involvement of alternative pathways in their regulation for the Muntries extract. Further molecular investigations, showed that Kakadu Plum inhibited the NF-кB pathway, but not the p44/42 mitogen activated protein kinase (MAPK) pathway. Collectively, these results demonstrate potential anti-inflammatory activities of native Australian fruits, in particular Kakadu Plum, in LPS-activated murine macrophages, thus confirming the potential biological activities of these fruits.

Four native Australian fruits, Illawarra Plum (Podocarpus elatus Endl., Podocarpaceae), Kakadu Plum (Terminalia ferdinandiana Exell, Combretaceae), Muntries (Kunzea pomifera F. Muell., Myrtaceae) and Native Currant (Acrotriche depressa R.Br., Epacridaceae) were examined for antioxidant and cellular protective activities. Each fruit showed significantly greater antioxidant activity than a blueberry (Vaccinum sp., cv. Biloxi) reference with Kakadu Plum exhibiting 13.3-fold and 2.4-fold activity of blueberry in the ferric ion reducing antioxidant power (FRAP) and oxygen radical absorbance capacity (ORAC-H) assays, respectively. A lyophilised polyphenolic-rich extract of Kakadu Plum exhibited the greatest cellular antioxidant activity (CAA assay) of 71.5 μmol QE/g, and was followed by Illawarra Plum, Native Currant and Muntries (46.3, 20.0 and 14.4 μmol QE/g, respectively). Polyphenolic-rich extracts of Kakadu Plum and Muntries (but not Illawarra Plum and Native Currant) extracts efficiently protected RAW 264.7 cells against hydrogen peroxide induced apoptosis in a dose-dependent manner. Kakadu Plum and Native Currant polyphenolic-rich extracts increased the Nrf2/Keap1 ratio, suggesting activation of the antioxidant response element (ARE) through the Nrf2/Keap1 complex. The results suggest Kakadu Plum exhibits the greatest antioxidant potential, exerting antioxidant activity through free radical scavenging and affecting two (Nrf2/Keap1) downstream transcription factors.

Selected native Australian fruits, muntries (Kunzea pomifera F. Muell., Myrtaceae), Tasmanian pepper berry (Tasmanian lanceolata R. Br., Winteraceae), Illawarra plum (Podocarpus elatus R. Br. ex Endl., Podocarpaceae), Burdekin plum (Pleiogynium timorense DC. Leenh, Anacardiaceae), Cedar Bay cherry (Eugenia carissoides F. Muell., Myrtaceae), Davidson's plum (Davidsonia pruriens F. Muell. var. pruriens, Davidsoniaceae), and Molucca raspberry (Rubus moluccanus var. austropacificus van Royen, Rosaceae), were evaluated as sources of antioxidants by 2,2-diphenyl-1-picrylhydrazyl and ferric reducing antioxidant power assays and compared with blueberry (Vaccinum spp. cv. Biloxi). The total reducing capacity of five fruits was 3.5-5.4-fold higher than that of blueberry, and the radical scavenging activities of muntries and Burdekin plum were 1.5- and 2.6-fold higher, respectively. The total phenolic level by Folin-Ciocalteu assay highly correlated with the antioxidant activity. Therefore, systematic research was undertaken to identify and characterize phenolic complexes. In the present study we report on the levels and composition of anthocyanins. The HPLC-DAD and HPLC/ESI-MS-MS (ESI = electrospray ionization) analyses revealed simple anthocyanin profiles of one to four individual pigments, with cyanidin as the dominating type. This is the first evaluation of selected native Australian fruits aiming at their utilization for the development of novel functional food products.

The leaf oils of the Australian members of the genus Podocarpus have been analyzed using GC and GC/MS. All species produced poor yields of oils (0.01–0.3%). The leaf oil of P. dispermus contained isopimara-9(11),15-diene (10.3%) and a C20 32(B) compound (12.7%) as principal components. Bicyclogermacrene (57%) was the principal component of P. drouynianus. Podocarpus elatus gave an oil in which α-pinene, (β-caryophyllene and bicyclogermacrene were the principal components. Bicyclogermacrene (27–44%), germacrene D (4–11%) and spathulenol (3–11%) were the principal components of the oil from P. grayae. Podocarpus lawrencei was one of only two Australian Podocarpus species to produce an oil (0.1–0.6%), which contained significant amounts of diterpenes. The main components were α-pinene (14–18%), β-caryophyllene (3–15%), spathulenol (0.8–19%), rimuene (0.2–30%), sandarocopimara-8(14), 15-diene (0.1–20%) and beyerene (7–9%). Podocarpus smithii produced a complex sesquiterpenic oil in which α-copaene (4...

Fruit antioxidants have many health benefits including prevention of cancer development. The native Australian bush fruit Illawarra plum (Podocarpus elatusEndl., Podocarpaceae) has a high content of anthocyanin-rich phenolics, with an antioxidant capacity at levels higher than most fruits. In the present study the molecular mechanisms of the anti-proliferative activity of Illawarra plum on colorectal cancer cells were investigated. Non-tumorigenic young adult mouse colonic (YAMC) cells and tumorigenic human colonic (HT-29) cells were treated with a polyphenolic-rich Illawarra plum extract (0–1000 μg/ml). Illawarra plum had anti-proliferative properties in only the cancer cells, with growth suppressed in a dose- and time-dependent manner. Treatment of HT-29 cells with Illawarra plum extract (500 μg/ml; 24 h) was also associated with a 2-fold increase in apoptosis, and a cell cycle delay in the S phase (PPPP

Molecular Ecology Resources Primer Development Consortium: et al., This article documents the addition of 512 microsatellite marker loci and nine pairs of Single Nucleotide Polymorphism (SNP) sequencing primers to the Molecular Ecology Resources Database. Loci were developed for the following species: Alcippe morrisonia morrisonia, Bashania fangiana, Bashania fargesii, Chaetodon vagabundus, Colletes floralis, Coluber constrictor flaviventris, Coptotermes gestroi, Crotophaga major, Cyprinella lutrensis, Danaus plexippus, Fagus grandifolia, Falco tinnunculus, Fletcherimyia fletcheri, Hydrilla verticillata, Laterallus jamaicensis coturniculus, Leavenworthia alabamica, Marmosops incanus, Miichthys miiuy, Nasua nasua, Noturus exilis, Odontesthes bonariensis, Quadrula fragosa, Pinctada maxima, Pseudaletia separata, Pseudoperonospora cubensis, Podocarpus elatus, Portunus trituberculatus, Rhagoletis cerasi, Rhinella schneideri, Sarracenia alata, Skeletonema marinoi, Sminthurus viridis, Syngnathus abaster, Uroteuthis (Photololigo) chinensis, Verticillium dahliae, Wasmannia auropunctata, and Zygochlamys patagonica. These loci were cross-tested on the following species: Chaetodon baronessa, Falco columbarius, Falco eleonorae, Falco naumanni, Falco peregrinus, Falco subbuteo, Didelphis aurita, Gracilinanus microtarsus, Marmosops paulensis, Monodelphis Americana, Odontesthes hatcheri, Podocarpus grayi, Podocarpus lawrencei, Podocarpus smithii, Portunus pelagicus, Syngnathus acus, Syngnathus typhle,Uroteuthis (Photololigo) edulis, Uroteuthis (Photololigo) duvauceli and Verticillium albo-atrum. This article also documents the addition of nine sequencing primer pairs and sixteen allele specific primers or probes for Oncorhynchus mykiss and Oncorhynchus tshawytscha; these primers and assays were cross-tested in both species.

The east Australian rainforests provide a unique system with which to study historic climate-driven habitat fragmentation. The long life span of rainforest conifers and consequent lag effects on genetic variation, offer insights into demographic stochasticity in small populations and persistence in increasingly fragmented systems. Microsatellite markers were used to investigate the genetic diversity and structure of Podocarpus elatus (Podocarpaceae), a long-lived rainforest conifer endemic to Australia. Twenty-seven populations throughout the east Australian rainforests were screened and two divergent regions separated by the dry Clarence River valley (New South Wales) were discovered. This biogeographic barrier may be referred to as the Clarence River Corridor. Niche modelling techniques were employed to verify the incidence of habitat divergence between the two regions. Significantly high inbreeding was detected throughout the species range with no evidence of recent bottlenecks. Most of the diversity in the species resides between individuals within populations, which suggest the species would be sensitive to the adverse effects of inbreeding, yet evidence suggests that these populations have been small for several generations. Slightly higher diversity estimates were found in the southern region, but it is likely that the species survived historic population contraction in dispersed refugia within each of these genetically differentiated regions.

The insect moulting hormone crustecdysone has been isolated from the Australian brown pine, Podocarpus elatus R.Br., and detected in a number of other Podocarpus species from various parts of the world. A series of acetates and acetonides of crustecdysone has been prepared, and the mass and nuclear magnetic resonance spectra of these compounds analysed. A simple micro method of measuring the rate of acetylation of hydroxy groups in steroids has been developed to determine the steric environment of these groups.