Peptides comprised entirely of β-amino acids, or β-peptides, have attracted substantial interest over the past 25 years due to their unique structural and chemical characteristics. β-Peptides form well-defined secondary structures that exhibit different geometries compared with their α-peptide counterparts, giving rise to their foldamer classification. β-Peptide foldamers can be functionalized easily and are metabolically stable and, together with the predictable side-chain topography, have led to the design of a growing number of bioactive β-peptides with a range of biological targets. The strategic engineering of chemical and topographic properties has also led to the design of β-peptide mimics of higher-order oligomers. More recently, the ability of these peptides to self-assemble into complex structures of controlled geometries has been exploited in materials applications. The focus of this mini-review is on how the unique structural features of β-peptide assemblies have been exploited in the design of self-assembled proteomimetic bundles and nanomaterials.

The first synthesis of carbon-stapled beta(3)-peptides is reported. The precursor beta(3)-peptides, with O-allyl beta-serines located in an i/i+3 relationship, were prepared on solid phase. We show that efficient ring-closing metathesis (RCM) of these new beta(3)-peptides proceeds smoothly either in solution or on an appropriate solid support. All products were generated with high selectivity for the E-isomer.

Reduction of hexavalent chromium was studied in three bench-scale continuous stirred tank reactors. The inoculum was a culture of Pseudomonas sp., capable of giving 83% to 87% chromate reduction in 72-h batch assays with 60 mg Cr(VI) L(-1) in synthetic medium. The continuous culture studies were conducted for about 100 days using synthetic feed containing different levels of chromate (5 to 124 mg L(-1)) at 28 degrees to 30 degrees C and pH 6.8. The feed rate was varied over the range 0.5 to 1 L d(-1) to obtain hydraulic retention time of 36 to 72 h. Chromate reduction efficiency was 81% to 91% and 100% for influent Cr(VI) concentrations of 15 to 124 and 5 mg L(-1), respectively, with a hydraulic retention time of 72 h. (c) 1994 John Wiley & Sons, Inc.

A positive attitude to a subject may be congruent with higher achievement; however, limited evidence supports this for students in undergraduate chemistry – this may result from difficulties in quantifying attitude. Therefore, in this study, the Attitude to the Study of Chemistry Inventory (ASCI) – a validated instrument to quantify attitude, was used to measure attitude to chemistry in 125 undergraduates studying an introductory course in chemistry, as part of a BSc Chemistry major. The 13 week course contained 4 summative assessments: practical (PRAC), tutorial (TUT), on-line web-based learning (OWL), and a final exam (FE). Sub-scales within ASCI which quantify the ‘affective’ and ‘cognitive’ components of attitude were determined. Firstly, for all 125 students, weak correlations (r) between the affective scale score and FE (r=0.275, P

The attitude towards the study of chemistry for new entrant chemistry students from a multi-national, regional, tertiary educational institution in the South Pacific was investigated using a purpose-designed diagnostic instrument. The Attitude toward the Study of Chemistry Inventory (ASCI) was used to quantify attitude in a cohort of first year undergraduate (n = 144) and foundation (n = 108) chemistry students. A similar, generally positive attitude to the study of chemistry was shown by both groups of students. Exploratory factor analysis using principle axis factoring and direct oblimin rotation was used to identify factors within the pooled data. Three factors accounted for more than 50% of the total variance, while Cronbach's alpha values for the factors 1, 2 and 3 were 0.92, 0.68 and 0.78, respectively. Factors 1 and 2 were consistent with known constructs of attitude, namely affective (factor 1) and cognitive (factor 2). However, the other factor (3) identified in this study was designated “Value”, which may reflect the students' choice of chemistry as a career path. ASCI may be a suitable tool for monitoring students' attitude throughout a degree and also to monitor the impact of novel approaches for teaching chemistry and engaging students.

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A library of 14-helical hexa β(3)-peptides was synthesized in order to determine the influence of sequence variation as well as staple size and location on conformational stability. From this study we show that appropriately stapled hexa-β(3)-peptides can allow for a number of variations without significant perturbation of the 14-helix.

Background: Pomegranate (Punica granatum L.) is universally known for its therapeutic properties due to its potential bioactive compounds. However, there is no established scientific study on antipsoriatic activity of pomegranate fruit rind. The aim of the study is to evaluate the anti-psoriatic activity of the isolated compounds and the extract from the fruit rind of P. granatum. In our previous study, the isolated compounds were evaluated for antioxidant potential. In continuation to the previous investigation, the present study is taken up to evaluate the extract and compounds for in vitro anti-psoriatic activity. Methods: Chromatographic techniques were employed to isolate the compounds from the aqueous acetone extract and in vitro anti-psoriatic activity was determined by thymidine phosphorylase inhibition assay. Results: From previous phytochemical investigation, three compounds were identified as Punicalagin, 2,3(S)-hexahydroxydiphenoyl-D-glucose and Punicalin. In the present study, the extract and the compounds were evaluated for anti-psoriatic activity. The results reveal that the isolated three compounds showed inhibitory activity of 89% to 95% against thymidine phosphorylase. Aqueous acetone extract also exhibited 87% inhibition. Conclusion: Punica granatum is an ideal plant for further investigation to prove its anti-psoriatic activity.