Australian Rainforests-A Living Museum of Natural Product Chemical Diversity

Australia is home to some of the oldest continuously rainforested ecosystems on earth. These forests contain a rich diversity of unique flora that reflect their origins from ancestors that were once widespread on the supercontinent Gondwana. Although rainforests represent 3% of Australian native forests (36,000 km²) and cover only 0.024% of earths land area, they contain ~3,800 gymnosperm and angiosperm species from 187 families and 942 genera. This phylogenetically diverse flora contains a rich diversity of natural products. The antiquity of the Australian rainforest flora matches with ancient biosynthetic lineages, and this has resulted in their natural product chemistry being remarkably diverse. Only 10% of the rainforest species have been investigated, but these studies have yielded almost 2,400 constituents. This contribution discusses the diversity of Australian rainforest derived natural products in relation to current knowledge on the origins, phylogenetic diversification and dispersal of seed plants. Ancient lineages appear to be reservoirs of high chemical diversity, and this highlights Australia's rainforests as a living museum of natural product chemical diversity. This volume highlights key highly bioactive natural products that have been isolated from Australian rainforest species and discusses recent NMR spectroscopic methods that have been developed to help identify unique molecules in complex mixtures in Australian rainforest species. It also discusses the significant contribution that Australian rainforest derived natural products play in our understanding of worldwide seed plant chemical diversity.