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Consumption of certain phenolics in the diet is considered beneficial to human health. In this study, individual phenolics were measured by diode-array HPLC at monthly intervals in the peel of Granny Smith, Lady Williams, and Crofton apple cultivars stored in air at 0 degrees C for 9 months. The concentrations of total phenolics significantly differed among the cultivars examined, with Lady Williams peel having significantly more phenolics (over 4000 microg x g(-1) peel fresh weight) than Crofton (2668 microg x g(-1) peel fresh weight) and Granny Smith, which had the lowest concentration of total phenolics (1275 microg x g(-1) peel fresh weight). There were also significant differences in individual phenolics among cultivars and during storage. Quercetin glycosides were the only flavonols identified, with quercetin rhamnoglucoside being the most abundant phenolic in the peel. Chlorogenic acid was the major cinnamic acid derivative, with high concentrations, up to 412 microg x g(-1)) peel fresh weight, in Crofton peel. A pre-storage diphenylamine (DPA) treatment had few significant effects on peel phenolic metabolism. Where differences did occur, fruit treated with DPA retained higher concentrations of total peel phenolics during storage than fruit not treated with DPA. Storage of all cultivars for up to 9 months in air at 0 degrees C induced few significant changes in the peel phenolic concentrations. This indicates that phenolic metabolism in apple peel is relatively stable, and the health benefits of phenolics in apple peel should be maintained during long-term storage.

Two germacradienols, 4-β-hydroxygermacra-1(10),5-diene (β-germacrenol) and 6-α-hydroxygermacra-1(10), 4-diene (kunzeaol) were identified in the solvent extracts of members of the family Myrtaceae. Acid solvolysis associated with steam distillation or leaf ageing causes these germacradienols to rearrange to a mixture of (+)-δ-cadinene, α-cadinol, τ-cadinol, α-muurolol, τ-muurolol and associated sesquiterpenoids. Copyright © 2001 John Wiley & Sons, Ltd.

The sesquiterpenoids (+)-δ-cadinene, epicubenol and cubenol in the essential oils of the Myrtaceae are by-products of the acid-solvolysis of the sesquiterpene alcohols cubebol and epicubebol. This solvolysis can occur during leaf ageing or steam distillation. Significant proportions of these compounds can be found in many members of the Myrtaceae, most notably commercial tea tree (Melaleuca alternifolia and M. linariifolia). Copyright © 2000 John Wiley & Sons, Ltd.

The steam distillates of the family Myrtaceae are often found to contain the three isomeric sesquiterpene alcohols, β-, β- and γ-eudesmol. Associated with these alcohols but not steam-distilled with them are two hydrates of eudesmol, cryptomeridiol and 4-epicryptomeridiol, compounds which have not been previously reported in the Myrtaceae. These five alcohols are the major by-products of the hydrolysis of hedycaryol, which can occur during leaf ageing or distillation. The use of H218O during distillation implicated the presence of hedycaryol prior to distillation by trapping the eudesmyl-carbocation formed during the hydrolysis. Copyright © 2000 John Wiley & Sons, Ltd.

The minimum inhibitory concentrations (MIC) of 60 terpenoids against Pseudomonas aeruginosa, Escherichia coli, Staphylococcus aureus and Candida albicans have been determined. Hierarchical cluster analysis was used to group the compounds into five groups according to their activity patterns against the four microorganisms. K-Means cluster analysis was then used to confirm these groupings and to show the differences in the activity patterns of the groups. Ten molecular properties of the terpenoids, either calculated via molecular modelling or determined by direct measurement, were then used as variables in a forward stepwise discriminant analysis to identify which variables discriminated between groups. Low water solubility of Group IV compounds, mainly hydrocarbons and acetates, was found to be associated with their relative inactivity. The remaining groups, all containing oxygenated terpenoids, showed characteristic but distinct activity patterns towards the four test organisms. Hydrogen bonding parameters were found to be associated with antimicrobial activity in all cases. Activity against Gram-negative E. coli and P. aeruginosa was associated with a combination of a hydrogen bonding and size parameters. This was not found to be the case for the Gram-positive S. aureus or the yeast C. albicans. Copyright © 1999 John Wiley & Sons, Ltd.

A hydrodistilled oil obtained from the leaves of Leucas milanjiana Gurke (Lamiaceae) was analysed by capillary GC and GC-MS. The leaf volatile oil contained 30 components, out of which 26 were identified. The predominant components were found to be β-cubebene (38.15%), α-pinene (19.71%), trans-caryophyllene (7.41%) and α-terpinolene (5.34%). The results are qualitatively and quantitatively at variance with data on other Leucas species and may therefore be of some chemotaxonomic significance for the genus. Copyright © 2006 John Wiley & Sons, Ltd.

Fatty acid compositions and lipid contents of five common table species of marine fish from temperate Australian waters were determined for samples taken during two seasons (four species) and three locations of markedly differing latitude (one species). Variabilities in total lipid extract and phospholipid fatty acid compositions were assessed between samples of each species, as well as between individuals of the same sample. These were then compared with data obtained for the other species analysed. The highest n3 polyunsaturated fatty acid (PUFA) content lipids were found in fish from colder waters (southern locations and spring season catches). The leaner species were found to have much more stable lipid characteristics with changes in the water temperature at sampling.

Gamma-irradiation preservation of two species of Australian marine fish (Black Bream and Redfish) resulted in no significant changes in their fatty-acid compositions, even when performed at up to three times the commonly recommended maximum dose for fish. Vitamin E loss was evident in some fillets but could not be correlated with the treatment dosage. All irradiated fillets were found to have vitamin E contents above the levels believed to be desirable for human consumption, relative to the amounts of accompanying polyunsaturated fatty acids.

A method for the rapid identification of fish species by high performance liquid chromatographic (HPLC) analysis of water-soluble sarcoplasmic protein extracts is described. The method relies on the visual comparison of a star-symbol plot constructed from the sample's HPLC profile with those obtained from the mean profile data of morphologically identified species. A library of plots is presented for 15 common edible marine fish species from eastern Australian waters, but any suitable data can be used for star construction. The data presented are applicable to the identification of samples from any season or location, whether they are raw, gamma-irradiated, or dried with infra-red radiation. The procedure involves a single 10 min extraction followed by a 60 min analysis, without the use of an internal standard.

Analysis of the volatile constituents of melon by HRGC-MS has led to the identification of a number of compounds not previously reported in other varieties. These compounds include a range of thioether and several diesters derived from butane-2,3-diol and propane-1,2-diol. The properties of the thioethers esters are of considerable sensory importance and hence play a role in determining consumer preference.

Fatty acid compositions and lipid levels of five common table varieties of marine fish from temperate Australian waters were determined. Nutritionally important values were calculated and compared with those of species from similar waters in the northern hemisphere. P/S and n-3/n-6 ratios, and the levels of arachidonic (AA) and docosahexaenoic (DHA) acids in the lipids were comparable for the two, but the Australian species had lower eicosapentaenoic acid (EPA) levels. Oils from Australian fish were shown to have nutritional properties as beneficial as their northern hemisphere counterparts.

The volatile components from the fruit of the Pistacia lentiscus tree were analyzed by capillary gas chromatography (CGC) and CGC-mass spectrometry. The major components were the monoterpenes α-pinene, β-pinene, myrcene and limonene. Several sesquiterpenes, aliphatic esters, ketones, and phenolic compounds such as thymol and carvacrol were also identified.