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Background: The seeds of Monodora myristica, a tropical plant belonging to the family Annonaceae, are widely used as condiments in the preparation of a number of African delicacies, to impart or enhance flavour. Their use is largely due to the volatile and fixed oils contained in the nuts.Objective: To screen for the acute toxicity (LD50) profile, determine the physicochemical properties, as well as carry out GC-MS analysis of the seed oil of Monodora myristica.Method: The acute toxicity screening was done using Lorke’s method. Physicochemical profile of the oil was determined using standard methods. GC-MS analysis of the oil sample was also carried out, using Shimadzu GCMS-QP2010SE.Results: The acute toxicity study showed that the oil sample had an LD50 of 316 mg/kg. The acid value was determined to be 9.27 mg KOH/g oil, while saponification value was 194.95 mg KOH/g oil. GC-MS analysis of the oil revealed that it contained fatty acids such as n-hexadecanoic acid, cis-vaccenic acid and 9,12-octadecadienoic acid; as well as terpinoids such as alpha-terpineol and alpha-cadinol.Conclusion: Results of the toxicological screening indicates that Monodora myristica oil is moderately toxic as the LD50 was within 50 – 500 mg/kg range. The oil has a relatively high tendency to go rancid due to the high acid value of 9.27 mg KOH/g oil.

This project, comprising of twelve original compositions and accompanying commentary, explores several key concepts that play a significant role in my creative practice, including the deconstruction and reassembly of materials; non-linear media; geometric construction of musical patterns; interactive audience elements; technology; and probability. Discussed across four chapters, these concepts lead to the development of unique compositional techniques and processes that feature heavily in my work. Chapter one focusses on deconstruction and non-linearity, from ensemble-led modularity to large-scale prerecorded compositions for radio. Chapter two is a study of how random elements and audience interaction can be facilitated through the use of technology, and takes examples from my generative audiovisual artworks. Chapters three and four cover geometry: introducing the mathematical concepts of perfect balance and aperiodic order, and discussing their use in my installations and compositions for orchestra. Throughout the project, a consideration of performance spaces and the audience experience is maintained, and the variety of ways a technique might be applied across different settings is explored.

The organic polymer lignin is a component of plant cell walls, which like (hemi)-cellulose is highly abundant in nature and relatively resistant to degradation. However, extracellular enzymes released by natural microbial consortia can cleave the β-aryl ether linkages in lignin, releasing monoaromatic phenylpropanoids that can be further catabolised by diverse species of bacteria. Biodegradation of lignin is therefore important in global carbon cycling, and its natural abundance also makes it an attractive biotechnological feedstock for the industrial production of commodity chemicals. Whilst the pathways for degradation of lignin-derived aromatics have been extensively characterised, much less is understood about how they are recognised and taken up from the environment. The purple phototrophic bacterium Rhodopseudomonas palustris can grow on a range of phenylpropanoid monomers and is a model organism for studying their uptake and breakdown. R. palustris encodes a tripartite ATP-independent periplasmic (TRAP) transporter (TarPQM) linked to genes encoding phenylpropanoid-degrading enzymes. The periplasmic solute-binding protein component of this transporter, TarP, has previously been shown to bind aromatic substrates. Here, we determine the high-resolution crystal structure of TarP from R. palustris as well as the structures of homologous proteins from the salt marsh bacterium Sagittula stellata and the halophile Chromohalobacter salexigens, which also grow on lignin-derived aromatics. In combination with tryptophan fluorescence ligand-binding assays, our ligand-bound co-crystal structures reveal the molecular basis for high-affinity recognition of phenylpropanoids by these TRAP transporters, which have potential for improving uptake of these compounds for biotechnological transformations of lignin.