A simple 96-well microplate method for estimation of total polyphenolic content in seaweeds

Seaweed polyphenols are potent antioxidants and have also been shown to have α-glucosidase inhibiting activity. In our continuous efforts to develop new marine-based nutraceuticals and functional food ingredients, we have investigated many algal species collected on the Atlantic coast of Canada. A simple method for estimating the total polyphenol content in seaweeds and their extracts was developed based on the classic Folin-Ciocalteau colorimetric reaction. By using the 96-well microplate and a microplate reader, this new method saves experimental time, significantly reduces the amount of sample required, handles large number of samples in one experiment, and also improves the repeatability of the results.

A number of algal samples collected on the seashore of Nova Scotia, Canada, were analyzed for their levels of polyphenol content using this microplate-based method. The antioxidant activity of these samples was also assessed by using DPPH (2, 2-diphenyl-1-picrylhydrazyl) radical scavenging assay. The results showed that there is a strong correlation between the total polyphenol content and the potency of antioxidant effect.

Antidiabetic properties of polysaccharide- and polyphenolic-enriched fractions from the brown seaweed Ascophyllum nodosum

We screened seaweed species from Atlantic Canada for antidiabetic activity by testing extracts for α-glucosidase inhibitory effect and glucose uptake stimulatory activity. An aqueous ethanolic extract of Ascophyllum nodosum was found to be active in both assays, inhibiting rat intestinal α-glucosidase (IC50 = 77 μg/mL) and stimulating basal glucose uptake into 3T3-L1 adipocytes during a 20-minute incubation by about 3-fold (at 400 μg/mL extract). Bioassay-guided fractionation of the A. nodosum extract showed that α-glucosidase inhibition was associated with polyphenolic components in the extract. These polyphenolics, along with other constituents appeared to be responsible for the stimulatory activity on glucose uptake. However, attempts to further concentrate this activity through fractionation techniques were unsuccessful. A crude polyphenol extract (PPE), an enriched polyphenolic fraction (PPE-F1) and a polysaccharide extract (PSE) were prepared from commercial A. nodosum powder and administered to streptozotocin-diabetic mice for up to 4-weeks by daily gavage at 200 mg/kg body mass. PPE and PPE-F1 improved fasting serum glucose level in diabetic mice; however, the effect was only statistically significant at day 14. In addition, PPE-F1 was shown to blunt the rise in blood glucose after an oral sucrose tolerance test in diabetic mice. Mice treated with PPE and PPE-F1 had decreased blood total cholesterol and glycated serum protein levels compared with untreated diabetic mice, whereas PPE also normalized the reduction in liver glycogen level that occurred in diabetic animals. All 3 A. nodosum preparations improved blood antioxidant capacity.

On a établit une recherche d’un produit anti-diabétique, parmi les algues locales de la région Atlantique du Canada, en examinant la capacité d’un effet inhibiteur de l’enzyme α-glucosidase et une stimulation de l’incorporation cellulaire du glucose. Un extrait éthanol-aqueux de Ascophyllum nodosum nous a donné une activité positive chez les deux essais, une inhibition de l’α-glucosidase provenant de l’intestin du rat (IC50 = 77 μg/mL) et puis une stimulation triple, à une concentration de 400 μg/mL, de l’incorporation du glucose dans les adipocytes 3T3-L1 durant une période de 20 minutes. L’extrait de A. nodosum a été divisé, guidé par les résultats biologiques, et a ainsi démontré la présence d’éléments polyphénoliques associé à l’inhibition de l’α-glucosidase. Ces éléments polyphénoliques ainsi que d’autres semblent être responsables de l’incorporation stimulée du glucose. Il a été impossible de raffiner cette activité lors d’une division des composants. Un extrait brut polyphénolique (PPE), un extrait enrichi polyphénolique (PPE-F1) et puis un extrait polysaccharide (PSE) furent préparés d’une poudre commerciale de A. nodosum et utilisés dans une étude utilisant des souris, rendues diabétiques par injections de streptozotocin, traitées par un gavage journalier de l’extrait 200 mg/kg du poids corporel durant une période de 4 semaines. Le taux du glucose sanguin à jeun des souris fut moins élevé en présence des extraits qu’en leurs absence. Cependant, l’effet était seulement significatif au jour 14. Les résultats étant toutefois variables. En plus, lors d’un essai oral de la tolérance au sucrose chez la souris diabétique, l’extrait PPE-F1 a empêché l’augmentation du taux du glucose sanguin. Les extraits PPE et PPE-F1 ont réduit le taux de cholestérol sanguin et les niveaux de glycation des protéines en comparaison de ces niveaux en absence des extraits tandis que l’extrait PPE a présenté une réduction du niveau de glycogène du foie chez les souris diabétiques. Les trois extraits de A. nodosum ont tous amélioré la capacité antioxidante du sang.

Development of a salmon protein hydrolysate that lowers blood pressure

A salmon protein hydrolysate (SPH) was developed containing several angiotensin I-converting enzyme (ACE) inhibitory tripeptides the most abundant of which were Val-Leu-Trp, Val-Phe-Tyr, and Leu-Ala-Phe. Simulated digestion experiments showed that active constituents of SPH would survive in the digestive tract and be available for absorption into the bloodstream. In fact, ACE inhibitory activity was improved following simulated digestion suggesting that there were larger peptides in SPH that might contribute to bioactivity in vivo. A single oral dose (1,500 mg/kg body mass) of SPH significantly lowered blood pressure in spontaneously hypertensive rats (SHR). The treatment of SHR with either SPH fraction (<3,000 Da) or SPH fraction (>3,000 Da) reduced blood pressure. We conclude that the ability of SPH to lower blood pressure is due to a combination of ACE inhibitory tripeptides as identified, as well as additional unknown, peptide species that are generated during digestion of SPH in the gastrointestinal tract.

Production and bioavailability of calcium and magnesium salts of omega-3 fatty acids

In order to provide an alternative to traditional liquid fish oil gelatin capsules, we developed a solid, powdered form of omega-3 fish oil concentrate by forming calcium- and magnesium-fatty acid salts. These salts were produced using a concentrated fish oil ethyl ester that contained in excess of 60% omega-3 fatty acids. The bioavailability of these omega-3 salts was compared with that of fish oil ethyl ester in mice. Animals were given 8 mg of omega-3 fatty acid ethyl ester concentrate (control), calcium- or magnesium-omega-3 salts daily for three weeks. The omega-3 salt products resulted in omega-3 fatty acid content in serum and red blood cell membranes comparable to that produced by the ethyl ester supplementation. In addition, fecal excretion of omega-3 fatty acids was not increased by the presence of calcium or magnesium. In fact, there was a tendency for less omega-3 fatty acids to be excreted.

Bottersnikes and other lost things : a celebration of Australian illustrated children's books

This is a history of illustrated Australian children's books published between 1845 and 2008 that emphasises the lesser known elements of the Australian child's literary history. Beyond the icons, such as May Gibbs' Snugglepot and Cuddlepie and Dorothy Wall's Blinky Bill, lie a wealth of illustrated books that broaden the potential for further research. Bottersnikes and Other Lost Things with over 400 full colour illustrations, is a tangible resource giving researchers the potential to expand our understanding of Australian children's literature: Advertising and ephemeral children's books provide insight into the varied nature children's reading from the turn of the 20th century; The educational reading reveals the expectations of the adults who wrote the School Papers and Readers and the aspirations they had for their readership; Attitudes to cultural difference across this period is remarkable for the overt nature of the racist portrayal of Indigenous Australians during the 19th and first half of the 20th centuries. These are some of the aspects of the Australian child's literary heritage explored for the first time in this history of Australian children's literature.

Double disability : lived experience of Australian tertiary students with ME/CFS

This research is the exploration of the lived experience of tertiary students in Australia with the medical condition usually known as ME/CFS (Myalgic Encephalomyelitis /Chronic Fatigue Syndrome) seeking to explore issues of equity and human rights from the perspective of the Disability Discrimination Act 1992. Students feel that their difficulties are not caused just by the illness itself but by the failure of the tertiary institutions to understand the effects of this illness on them, the student, especially within the areas of accommodations and assessments. Their lived experiences are studied to ascertain if their experiences differ from those of other tertiary students. Forty participants came from every state and territory of Australia and twenty -four of Australia's universities as well as eight Technical and Further Education/Open Training Education Network (TAFE/OTEN) colleges are represented. The selection of the chosen methodology, Critical Ethnography from a Habermasian perspective, has been circumscribed by the medical condition which placed limitations on methodology and also data gathering methods. Non-structured stories, in which the participants wrote of their lived experience as students, were considered the most appropriate source of data. These were transmitted by electronic mail (with some by postal mail) to the researcher. A short questionnaire provided a participant background to the stories and was also collated for a composite overview of the participants. The stories are analysed in a number of ways: six selected stories are retold and the issues arising from these stories have been weighed against the remainder of the stories. Four intertwined themes were constructed from the issues raised in each story. Apparent infringements of the Disability Discrimination Act (1992) which impact on quality of life, human rights and equity are found. No accommodations are being made by the academic institutions for the cognitive dysfunctions and learning difficulties. Students are stigmatised and lack credibility to negotiate appropriate academic accommodations. A possible means of improving the ability of students to negotiate appropriate accommodations is explored. Finally the researcher reflects on her own involvement in the research as an 'insider' researcher.

Effectiveness of recording in primary science : a study of the ability of junior primary school pupils to use drawing as an effective method of communication in science lessons

Drawing as a means of recording is a very common practice in junior primary science lessons. This is largely due to the availability of necessary materials. Also, most youg children have some degree of drawing skill and enjoy drawing activities. Since 1956 the science curriculum to be implemented in primary classrooms in Victoria has changed from one that was based largely on nature study (biological) to one that includes physical and technological aspects. Further, there have been changes in the teaching methodologies advocated for use in science lessons. A modified Interactive Teaching Approach was used for the studies. Drawing was the main means by which the children recorded information. The topic of 'shells' was used to enable collection of data about the children's enjoyment of the activity and satisfaction with their achievement. This study was replicated using the topic 'rocks'; again data were collected concerning satisfaction and enjoyment. During a series of lessons on 'snails' data were collected concerning the achievement of 'process' and 'objective' purposes that teachers might have in mind when setting a drawing activity. In addition to providing data about purposes the study stimulated some questions regarding the techniques the children had used in their drawings. Accordingly, data concerning the use of graphic techniques by the children were collected during a series of lessons on 'oils'. The data collected and analysed in the various studies highlighted the value of drawing in junior primary school science lessons. It also validated strategies developed by the author and designed to help teachers and children use drawing effectively in science activities.

Poetry and silence : "a sequence of disappearances"

[No Abstract]

Developing the textual turn : tracking the grammar of research case records

During action research projects a great deal of written material is produced. Some of this is data generated about the project, some about the process of the research and some is reflective writing about the researcher(s). In this article I propose that a deliberate focus on the tracking of texts might be helpful in action research, particularly if the inquiry is working within significant constraints. Working with a range of documents and informed by the work of Dorothy Smith on the texting of ruling relations, I show how a multiagency project based in one school slipped away from its original community development goals into a more 'professional service' model. I also show how the project was able to resist partially the requirement by the funding body to use a rational strategic planning model through the production of taped conversations and meta-analytic papers. Although this is a single case, I contend that this example points to the potential utility of an explicit focus on the textual practices of action research.

Study of culture and organisational change at a TAFE Institute

Barton Institute of Technical and Further Education, a metropolitan Victorian TAFE institute was chosen for the case study. The research methodology included designing and administering a survey and selecting a number of performance indicators.

Child-focused and child-inclusive divorce mediation : comparatice outcomes from a prospective study of postseparation adjustment

This study compared outcomes over 1 year for two groups of separated parents, who attended two different forms of brief therapeutic mediation for entrenched parenting disputes. The two interventions each targeted psychological resolution of parental conflict, enhanced parental reflective function, and associated reduction of distress for their children. The child-focused (CF) intervention actively supported parents to consider the needs of their children, but without any direct involvement of the children, while the child-inclusive (CI) intervention incorporated separate consultation by a specialist with the children in each family, and consideration of their concerns with parents in the mediation forum. Repeated measures at baseline, 3 months, and 1 year postintervention explored changes over time and across treatments in conflict management, subjective distress, and relationship quality for all family members. Enduring reduction in levels of conflict and improved management of disputes, as reported by parents and children, occurred for both treatment groups in the year after mediation. The CI intervention had several impacts not evident in the other treatment group, related to relationship improvements and psychological well-being. These effects were strongest for fathers and children. Agreements reached by the CI group were significantly more durable, and the parents in this group were half as likely to instigate new litigation over parenting matters in the year after mediation as were the CF parents. The article explores the potential of CI divorce mediation to not only safely include many children in family law matters related to them, but also to promote their developmental recovery from high-conflict separation, through enhanced emotional availability of their parents.