Escalation (macroevolutionary increase) or divergence (disparity between relatives) in trait valu... more Escalation (macroevolutionary increase) or divergence (disparity between relatives) in trait values are two frequent outcomes of the plant-herbivore arms race. We studied the defences and caterpillars associated with 21 sympatric New Guinean figs. Herbivore generalists were concentrated on hosts with low protease and oxidative activity. The distribution of specialists correlated with phylogeny, protease and trichomes. Additionally, highly specialised Asota moths used alkaloid rich plants. The evolution of proteases was conserved, alkaloid diversity has escalated across the studied species, oxidative activity has escalated within one clade, and trichomes have diverged across the phylogeny. Herbivore specificity correlated with their response to host defences: escalating traits largely affected generalists and divergent traits specialists; but the effect of escalating traits on extreme specialists was positive. In turn, the evolution of defences in Ficus can be driven towards both esc...
Plants and microorganisms produce a plethora of chemical compounds called secondary metabolites a... more Plants and microorganisms produce a plethora of chemical compounds called secondary metabolites as a result of their various biochemical and metabolic processes. Many of these chemical compounds have been identified and developed into useful products that are appreciated as pharmaceutical drugs, agrochemical compounds or as fine chemicals for the synthesis of other useful products. Research aimed at the identification of these naturally occurring compounds and the sources from which thay are obtained, as well as the analysis of their respective biological activities, is necessary for further developmental studies. Also, studies aimed at the development of appropriate plant agronomy and culture media and techniques can lead to the cultivation and extraction of these useful chemicals from plants and microorganism sources for their mass production of pharmaceutical, agricultural, cosmetic and fine chemical industries. In this paper, the composition of naturally occurring from some of t...
The growing global phenomena of a triple-helical culture of research and innovation between Unive... more The growing global phenomena of a triple-helical culture of research and innovation between Universities, Government and Industries has been increasingly appreciated the world over. This trilateral partnership is centred on the premises that internal transformations within the three entities guided by suitable government policies and driven by collaborative networking and dialogue between the partners can usher in the anticipated outcomes. It is within this nexus that partners can rely on each other to accomplice the goals and aspirations and general advancement and break throughs in knowledge creation and technological advancement. The concept of triple helical culture in PNG may be a positive contribution to enhancing a knowledge-based economy. It is inevitable that the Government of PNG, through the Office for Higher Education has been proactive in initiating such partnership and encouraging Universities to be more innovative, enterpreneurial and self-supporting. This paper prese...
Here we report the discovery and synthesis of complex polybrominated p-terphenyl ethers isolated ... more Here we report the discovery and synthesis of complex polybrominated p-terphenyl ethers isolated from a mushroom (Boletopsis sp.) used as a traditional medicine by the Kiovi people in the highlands of Papua New Guinea. Boletopsins 13 and 14 represent the first report of polybrominated fungal metabolites to be produced by a terrestrial fungus. The synthetic method employs 2,4,4,6-tetrabromo-2,5-cyclohexadienone to achieve selective polybromination of the extended aromatic system in a selective and sequential manner.
Escalation (macroevolutionary increase) or divergence (disparity between relatives) in trait valu... more Escalation (macroevolutionary increase) or divergence (disparity between relatives) in trait values are two frequent outcomes of the plant-herbivore arms race. We studied the defences and caterpillars associated with 21 sympatric New Guinean figs. Herbivore generalists were concentrated on hosts with low protease and oxidative activity. The distribution of specialists correlated with phylogeny, protease and trichomes. Additionally, highly specialised Asota moths used alkaloid rich plants. The evolution of proteases was conserved, alkaloid diversity has escalated across the studied species, oxidative activity has escalated within one clade, and trichomes have diverged across the phylogeny. Herbivore specificity correlated with their response to host defences: escalating traits largely affected generalists and divergent traits specialists; but the effect of escalating traits on extreme specialists was positive. In turn, the evolution of defences in Ficus can be driven towards both esc...
Plants and microorganisms produce a plethora of chemical compounds called secondary metabolites a... more Plants and microorganisms produce a plethora of chemical compounds called secondary metabolites as a result of their various biochemical and metabolic processes. Many of these chemical compounds have been identified and developed into useful products that are appreciated as pharmaceutical drugs, agrochemical compounds or as fine chemicals for the synthesis of other useful products. Research aimed at the identification of these naturally occurring compounds and the sources from which thay are obtained, as well as the analysis of their respective biological activities, is necessary for further developmental studies. Also, studies aimed at the development of appropriate plant agronomy and culture media and techniques can lead to the cultivation and extraction of these useful chemicals from plants and microorganism sources for their mass production of pharmaceutical, agricultural, cosmetic and fine chemical industries. In this paper, the composition of naturally occurring from some of t...
The growing global phenomena of a triple-helical culture of research and innovation between Unive... more The growing global phenomena of a triple-helical culture of research and innovation between Universities, Government and Industries has been increasingly appreciated the world over. This trilateral partnership is centred on the premises that internal transformations within the three entities guided by suitable government policies and driven by collaborative networking and dialogue between the partners can usher in the anticipated outcomes. It is within this nexus that partners can rely on each other to accomplice the goals and aspirations and general advancement and break throughs in knowledge creation and technological advancement. The concept of triple helical culture in PNG may be a positive contribution to enhancing a knowledge-based economy. It is inevitable that the Government of PNG, through the Office for Higher Education has been proactive in initiating such partnership and encouraging Universities to be more innovative, enterpreneurial and self-supporting. This paper prese...
Here we report the discovery and synthesis of complex polybrominated p-terphenyl ethers isolated ... more Here we report the discovery and synthesis of complex polybrominated p-terphenyl ethers isolated from a mushroom (Boletopsis sp.) used as a traditional medicine by the Kiovi people in the highlands of Papua New Guinea. Boletopsins 13 and 14 represent the first report of polybrominated fungal metabolites to be produced by a terrestrial fungus. The synthetic method employs 2,4,4,6-tetrabromo-2,5-cyclohexadienone to achieve selective polybromination of the extended aromatic system in a selective and sequential manner.
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Papers by Stewart Wossa