Recent trends in diabetes treatments show an increasing interest in traditional systems of medicine. Ayurveda, a traditional Indian system medicine, advocates a wide range of medicinal plants to treat diabetes. Although there have been numerous studies on extracts from these medicinal plants that demonstrate antidiabetic activity, scientific studies directed to the isolation, purification and identification of active ingredients responsible for the hypoglycemic activity and also the modes of action of these extracts/active ingredient(s) on glucose homeostasis have been often inconclusive or lacking except for a few cases. The aim of this present study was to identify and isolate a potent antidiabetic compound(s) from some extensively advocated Ayurvedic antidiabetic plants such as 'Trigonella foenum-graecum' Linn (TFG), 'Pterocarpus marsupium' Roxb (PM), 'Gymnema sylvestre' R.Br (GS) and 'Curcuma longa' Linn (CL). An in-house developed 'in vitro' tissue culture-based bioassay method was employed in the present study to determine the effects of plant extracts on insulin secretion from mouse pancreas tissues and on glucose uptake by mouse skeletal muscle tissues under both normoglycemic (5mM glucose) and hyperglycemic (12mM glucose) culture conditions. The results from our preliminary study indicated that all these plant extracts have beneficial effects on glucose homeostasis either by stimulating insulin or enhancing glucose uptake or activating both. In terms of their comparative effects on tissues that regulate glucose metabolism, the aqueous extracts of plants, PM and CL, were found to be more potent when compared with other studied aqueous extracts of plants TFG and and GS, within culture conditions.

Currently there is a need for an accurate and non-hazardous method to measure individual intake of a supplement in grazing sheep over a prolonged period. This paper examines the potential of fenbendazole (FBZ) as a marker of intake. The following five experiments aim to determine the relationship between oral ingestion of FBZ and the plasma concentrations of FBZ and its metabolites oxfendazole (OFZ) and FBZ-sulfone (SUL) after single, multiple and daily doses both in housed and grazing sheep and sheep infected with internal parasites. The results from these experiments indicate that OFZ+SUL concentrations in plasma are dependent on FBZ dose rate in housed and grazing animals with differences evident between different dose rates (P < 0.001). Variability of OFZ and SUL concentrations increase in grazing compared with housed animals. Area under the curve of metabolite concentrations was also shown to indicate dose rate regardless of the timing and frequency of dose. Stepwise regressions indicated that sampling every 48 h gave a good representation of area under the curve for different dose rates (R² = 0.951, P < 0.001). A significant separation of treatment means was achieved when samples were taken every 48 h and pooled during daily dosing with FBZ (P < 0.001). Finally gastrointestinal nematode infection did not affect OFZ and SUL concentrations after daily doses of FBZ. The results from these experiments indicate that FBZ is a useful and accurate marker of supplement intake in grazing animals.

The fatty acid profiles of Antarctic ('n' = 7) and non-Antarctic yeasts ('n' = 7) grown at different temperatures were analysed by gas chromatography-mass spectrometry. The Antarctic yeasts were enriched in oleic 18:1 (20-60 %), linoleic 18:2 (20-50 %) and linolenic 18:3 (5-40 %) acids with lesser amounts of palmitic 16:0 (<15 %) and palmitoleic 16:1 (<10 %) acids. The non Antarctic yeasts ('n' = 4) were enriched in 18:1 (20-55 %, with 'R. mucilaginosa' at 75-80 %) and 18:2 (10-40 %) with lesser amounts of 16:0 (<20 %), 16:1 (<20 %) and stearic 18:0 (<10 %) acids. By contrast, Saccharomyces cerevisiae strains ('n' = 3) were enriched in 16:1 (30-50 %) and 18:1 (20-40 %) with lesser amounts of 16:0 (10-25 %) and 18:0 (5-10 %) acids. Principal component analysis grouped the yeasts into three clusters, one belonging to the 'S. cerevisiae' strains (enriched in 16:0, 16:1 and 18:1), one to the other non-Antarctic yeasts (enriched in 18:1 and 18:2) and the third to the Antarctic yeasts (enriched in 18:2 and 18:3).

Volatile oils of 'Eremophila longifolia' F. Muell. (Myoporaceae) leaves were obtained by hydrodistillation and analysed using GC–MS. A total of 33 compounds were identified in the oils examined and a high degree of intraspecific variability in chemical composition between specimens occurring in separate geographic localities was found. Multivariate statistical analysis of chemical composition of volatile oils enabled classification of three chemotypes in this species.

Essential oils from the Australian Aboriginal medicinal plant 'Eremophila longifolia' (emu bush) were characterised using GC/MS and NMR, and antimicrobial capacity investigated using disc diffusion and broth dilution. Leaves were collected from various locations within New South Wales (NSW, Australia) and hydro-distilled for volatile leaf oils. Overall yield and oil constitution differed markedly according to the geographical region from which the plants were collected. 'E. longifolia' demonstrated a variety of chemotypes not yet recognised. Four further chemotypes are now recognised within NSW, in addition to the two previously characterised from other regions of Australia; the Northern Territory (NT) and the Murchison district in Western Australia (WA). Characterisation of NSW chemotypes revealed that here 'E. longifolia' does not produce the carcinogenic volatile compound, safrole, as previously described in the leaf oil from Murchison specimens (WA). Two separate chemotypes within NSW yielded oil as high as 7% w/w and 3.5% w/w consisting mostly of iso-menthone (70-90%) and karahanaenone (≈80%) respectively; marking these as the most abundant natural sources of these compounds so far described [3,4,5]. The two remaining chemotypes had a much lower yield, 0.2 and 0.7%, and were more similar to the chemotype found in the NT; leaf oils consisting of limonene (≈20%) and borneol (20-30%) respectively. Antimicrobial assays of volatile oils from the four chemotypes revealed a moderate to high antimicrobial capacity, varying with species and chemotype. Traditional (location specific) indigenous applications of the oils are consistent with these results. The essential oil from 'E. longifolia' may thus be a likely candidate for further investigation into cosmeceutical use addressing a similar market niche to that already successfully occupied by the essential oil of 'Melaleuca alternifolia' (tea tree oil) and more recently 'Backhousia citriodora' (lemon myrtle oil). Further investigations (wound healing, anti-inflammatory and cultivar chemotype requirements) are in progress.

This study aimed to determine the dose-dependent relationship between oral doses of fenbendazole (FBZ) and the plasma concentration of its metabolites, oxfendazole (OFZ) and fenbendazole-sulphone (SUL). Twenty five, two year-old, Merino wethers were equally allocated to treatment groups of different oral dose rates of FBZ (n = 5) and housed in individual pens. Treatment groups were designed to provide daily oral doses of 0.25, 0.5, 1.0, 2.0 and 4.0 mg/kg live weight of FBZ, suspended in water, for six days. Blood samples were collected from each animal at 48, 96, and 144 hours after administration of FBZ. Plasma was equally combined within each animal and analysed to determine concentrations of FBZ, OFZ and SUL. There was a positive linear relationship between FBZ dose rate and FBZ metabolite plasma concentration (R² = 0.991, P <0.001). Mean separation of plasma concentrations indicated significant differences (P <0.05) between treatments designed to provide 1.0, 2.0 or 4.0 mg/kg/day FBZ. Plasma concentrations of animals which received 0.25 or 0.50 mg/kg/day FBZ were significantly lower than other treatments (P <0.05). The results from this experiment provide preliminary support for the investigation of FBZ as a useful marker to estimate supplement intake of grazing animals.

Aim: A comprehensive analysis of the lipid profile [fatty acids, phospholipids (PL) and triacylglycerols (TAG), including the molecular species of PL and TAG] of 14 strains of yeast, seven designated as Antarctic and seven designated as non-Antarctic. These strains were: Antarctic: 'Cryptococcus watticus' CBS 9496, 'Cr. victoriae' CBS 8685, 'Cr. nyarrowii' CBS 8805, 'Leucosporidium antarcticum' CBS 8927, 'L. fellii' CBS 7287, 'Rhodotorula mucilaginosa' UNE 130a and 'Candida psychrophila' CBS 5956. Non-Antarctic: 'Cr. humicolus' ATCC 9949, 'C. albicans' ATCC 10231, 'R. mucilaginosa' ATCC 66034, 'Zygosaccharomyces rouxii' ATCC 2623, 'Saccharomyces cerevisiae' ATCC 18824, 'S. cerevisiae' ATCC 26603 and 'S. cerevisiae' ATCCC 26422. Methods: Cells were grown at 25°C or at 15°C for the non-Antarctic yeasts and at 15oC or at 5oC for the Antarctic yeasts. Lipids were isolated and total fatty acid compositions were analysed by Gas Chromatography-Mass Spectrometry. Phospholipid classes and their molecular species were determined by High Performance Liquid Chromatography-Electrospray Ionization-Mass Spectrometry (HPLC-ESI-MS). The regiospecific position of acyl groups of phospholipid molecular species was determined using ESI-MS-MS. Triacylglycerols and Diacylglycerols and their molecular species (nature of the fatty acid moieties in the sn-2 and sn-1,3 positions) were determined by HPLC-Atmospheric Pressure Chemical Ionization-Mass Spectrometry (HPLC-APCI-MS). ... Significance and Impact of the Studies: These are the first reports on detailed analyses of phospholipid and triacylglycerol molecular species in Antarctic yeasts. Moreover, they also provide new insights into the lipid components of non-Antarctic yeasts which to date have been largely concentrated on 'S. cerevisiae'. The data also provide novel information as to subtle but key changes in lipid molecular species in response to temperature.

The aim of this study was to determine the rate, variability and repeatability of intake by grazing sheep of a medicated feed block (MFB) containing fenbendazole and investigate if infection with gastrointestinal nematodes altered consumption patterns of the MFB in the same grazing mob. In Experiment 1, 30 Merino wethers were given access to an MFB for two separate 1-week periods, with blood sampling at Days 2, 4 and 6 of each period to determine MFB intake. In Experiment 2, the wethers were selected based on previous MFB intake and allocated to receive an oral dose of 10 000 'Trichostrongylus colubriformis' and 3000 'Haemonchus contortus' (anthelmintic susceptible) or a long acting anthelmintic. After 5 weeks, sheep were given access to an MFB (1.5 mg fenbendazole/g) and eight blood samples were taken over 2 weeks to determine intake. In Experiment 1, individual MFB intake in Week 1 and Week 2 was positively correlated (P = 0.002, R² = 0.287). Mean individual MFB intake in Experiment 1 and Experiment 2 was positively correlated (P = 0.008, R² = 0.047). In Experiment 2, more infected wethers (95%) consumed the MFB than did uninfected wethers (79%) (P < 0.001) and infected wethers ate significantly more MFB over the first 4 days (P = 0.041) of access. All infected sheep consumed sufficient MFB to receive a therapeutic dose and worm egg counts in infected sheep declined from 2165 epg to 120 epg in the first week of access to MFB. The decline in differences in MFB intake between infected and uninfected sheep corresponded to the decline in worm egg count, suggesting the existence of self-medication with parasitism accounting for intake differences.

High performance liquid chromatography-electrospray ionization tandem mass spectrometry was applied to the comprehensive analysis of phospholipids from seven Antarctic and seven non-Antarctic yeasts. Identification of specific fatty acyl moieties to the 'sn-1' and 'sn-2' positions of phosphatidylethanolamine (PE), phosphatidylcholine (PC), phosphatidylserine (PS) and phosphatidylinositol (PI) were determined by relative abundance of fragment ions associated with formation of carboxylate anions and loss of fragment ions as free fatty carboxylic acid and ketene. Modulations with growth temperature in fatty acyl moieties in the 'sn-1' and 'sn-2' positions were characterized. Principal component analysis demonstrated that PE, PC and to a lesser extent PS, but not PI, were grouped into three distinct clusters consisting of seven Antarctic yeasts '(Cryptococcus victoriae, Holtermanniella wattica, H. nyarrowii, Candida psychrophila, Leucosporidium fellii, Glaciozyma antarctica, Rhodotorula mucilaginosa)', four non-Antarctic yeasts '(C. albicans, Zygosaccharomyces rouxii, Cr. humicolus, R. mucilaginosa)' and three strains of 'Saccharomyces cerevisiae'.