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Abstract  

A project is underway to build and use a fission time projection chamber (TPC) to make high precision/accuracy measurements of neutron-induced fission cross sections to address issues in fast reactor design. A critical aspect of this program is to have thin TPC targets on thin backings with uniform deposits of the actinides. We have prepared, using vacuum deposition, 100–200 μg/cm2 deposits of 232Th, 235U and 238U on 30–100 μg/cm2 C backings with a measured thickness variation of <1.5%. To facilitate measurement of cross section ratios, we are preparing targets with an n-leaf clover design where each petal is a different nuclide.

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Authors: J. Pokorná, P. R. Venskutonis, V. Kraujalyte, P. Kraujalis, P. Dvořák, B. Tremlová, V. Kopřiva and M. Ošťádalová

Coffee beans contain a large amount of antioxidants, which are subjected to various changes during roasting. In this study, antioxidant potential of raw and roasted to different degree (light, medium, dark) C. arabica and C. robusta coffee beans was evaluated by the four antioxidant assay methods, TPC, FRAP, TEAC, and DPPH˙.

The obtained results revealed significant differences between the coffee types, roasting degree, and antioxidant activity assessment methods. FRAP and TPC appeared to be the most appropriate methods for revealing the differences in antioxidant potential of different coffee types and the effects of roasting. The results obtained by these methods were in good correlation. ABTS and DPPH? methods are not enough sensitive for the determination of roasting degrees.

In general, based on statistical data evaluation, antioxidant activity is more dependent on the coffee type than on the degree of roasting, however, the selection of analytical method may also be significant.

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Introduction The diamine used is 2-(3,5-diaminophenyl)benzimidazole, DAPBI, and the dichloride is terephthaloyl chloride, TPC. The products are a polymer in the condensation under 1:1 of DAPBI:TPC mole ratio in feed. They are

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Sorghum bicolor (L.) Moench contains various phenolic compounds such as anthocyanin. Eleven sorghum accessions were classified into five groups by grain colour and their antioxidant activities were measured as well as the contents of total phenolic compounds (TPC) and anthocyanins in sorghum grains. The grain colour was related to TPC content, but not to monomelic anthocyanin content. Moreover, the overall patterns of antioxidant activity levels in 2,2-Diphenyl-1-picrylhydrazyl (DPPH) or 2,2′-Azino-bis (3-ethylbenzothiazoline-6-sulfonic acid) (ABTS) assay were similar to those of the TPC content. Correlations between TPC and anthocyanin contents were statistically significant and positive (P < 0.05). TPC content showed also a strong positive correlation to DPPH and ABTS antioxidant activities. The results provide the basic data for breeding of sorghum varieties containing large amounts of antioxidants.

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Authors: A. Dutta, P. Gope, S. Banik, Md. Rahman, S. Makhnoon, M. Siddiquee and Y. Kabir

Milled rice from nine aromatic cultivars was evaluated for physicochemical, cooking, and antioxidant properties. Physical parameters measured were milling outrun, head rice yield (HRY), and appearance (size and shape). Cooking time, water uptake ratio and elongation ratio were determined to study their cooking quality. Chemical parameters included were amylose content (AC), protein content (PC), gel consistency (GC) and alkali spreading value (ASV). Total phenolic content (TPC) was measured using the Folin-Ciocalteu method, while ferric reducing antioxidant power (FRAP), total antioxidant capacity (TAC), and 1,1-diphenylpicrylhydrazyl (DPPH) radical scavenging activity were used to study their antioxidant activity. This study revealed all rice cultivars, except Basmoti-370 and Gopalbhog, showed HRY. Besides, all rice cultivars displayed high protein content. Significant variations (P<0.05) were found in TPC and the antioxidant activities of the rice cultivars. The correlation coefficient between the TPC and the antioxidant activities was strong and statistically significant (P<0.05).

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Authors: Éva Németh-Zámbori, Zsuzsanna Pluhár, Krisztina Szabó, Mahmoud Malekzadeh, Péter Radácsi, Katalin Inotai, Bonifác Komáromi and Katarzyna Seidler-Lozykowska

A pot experiment was carried out with lemon balm (Melissa officinalis L.) and thyme (Thymus vulgaris L.). Different water supply was applied: 25%, 40% and 70% saturation of soil water capacity (SWC). Morphological traits, biomass and phenolic type active ingredients were investigated.

Among the two species, main differences were registered in biomass and TPC. Lower SWC resulted in reduced biomass production of lemon balm, while the applied stress treatments did not effect the biomass of thyme. In lemon balm, highest TPC contents were measured in control plants both in shoots and roots but in thyme, the shoots showed a significantly increased TPC at the 25% SWC conditions. Neither the content of total flavonoids nor that of the rosmarinic acid was affected by the treatments. The antioxidant capacity proved to be in tight connection with the TPC in both species (r = 0.766–0.883). The rosmarinic acid content of lemon balm plants contributed to the antioxidant capacity, as well (r = 0.679–0.869).

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The outcome of various solvent extraction (water, methanol, acidic 50% methanol, 70% acetone, acidic 50% methanol followed by 70% acetone) on the total phenolic content (TPC) and antioxidant capacity of fruit pulp, seeds, leaves and stem bark of seabuckthorn (Hippophae rhamnoides L.) was investigated. The seabuckthorn extracts possess high phenolic content, 1666–13769 mg GAE/100 g d.w. The mean TPC was found highest in seeds (11148) followed by stem bark (10469), leaves (6330) and pulp (3579 mg GAE/100 g d.w.). In general, the 70% acetone and acidic 50% methanol followed by 70% acetone extracts was found to contain significantly higher TPC than those obtained in other extracting solvents. Antioxidant capacity in terms of IC50 value of pulp (3.39 mg ml−1) was up to 7.8 times higher than those reported for stem bark (0.43 mg ml−1) and up to 2.4 times higher than those found in seeds (1.4 mg ml−1). Further, antioxidant capacity by FRAP assay showed that the stem bark possess maximum antioxidant capacity (16.83) followed by seeds (15.26), leaves (12.73) and pulp (12.61), all as mM FeSO4. Significant correlation was found between TPC and antioxidant capacity by DPPH and FRAP assays.

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DPPH, Folin-Ciocalteau (FC) and peroxidase catalysed methods have been used to determine the free radical scavenging activity and total phenolic content (TPC) of two fermenting musts and thirty-four fresh juice of fruits and vegetables. Generally, a good correlation between the phenolic content and the scavenging activity was found. The red must showed catechin equivalent (CE) values almost one magnitude higher than the white one, while the CE behaviours in the course of the fermentation process appeared similar for two musts and for all the measurement methods. The FC results showed TPC values generally higher than those obtained by the enzymatic method, while the scavenging activity, expressed as CE in order to better correlate the results, showed lower values with the exception of citrus fruit juices for which the enzymatic response was twice of that obtained by the FC test. Furthermore, generally it was found that fruits presented CE values 2–3 times higher than those found in the vegetables. Finally, the results obtained demonstrate the applicability of the peroxidase catalysed coupling method to the TPC and antioxidant properties determination in wine, tea, fruits and vegetables.

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Summary  

The aims of this paper are to summarize Canadian government programs pertaining to research and development (R&D) and R&D support programs, and to propose a method for analyzing their socio-economic impact. The programs under investigation include:  • Canada Research Chairs •                Canada Millennium Scholarship Foundation •              Canada Foundation for Innovation •              Technology Partnerships Canada (TPC) •            Industrial Research Assistance Program (IRAP) •       Natural Sciences and Engineering Research Council (NSERC) •             Social Sciences and Humanities Research Council (SSHRC) •   Canada Institutes of Health Research (CIHR) •                Canadian Institute of Advanced Research (CIAR) •    Pre-Competitive Advanced Research Networks (PRECARN) • Networks of Centres of Excellence

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The procedure involving water and water-methanol extraction, RP-HPLC-C18 column chromatography with PDA detection was developed for determination of cinnamic acid and benzoic acid derivatives in grapevine’s dietary supplements (LV, RW, VIN, VIC, and DK) available on the Polish market. Phenolic acids were analysed before and after acidic and basic hydrolysis and identified against standards. Totalamount of studied phenolic acids determined by HPLC-PDA was compared with total polyphenols content (TPC) by Folin-Ciocalteu method. The average content of studied phenolic acids (70.54±0.21; 122.95±0.49; 87.67±0.10; 132.21±0.24; 266.78 ±0.39, and 18.16±0.09 mg/100 g d.m. (dry mass) for LV, RW, VIN, VIC, DK, and WW, respectively) were higher than the TPC (1489.91±0.39, 1648.19±0.14, 1574.38±0.33, 1643.64±0.12, 1984.75±0.97, and 715.55±0.36 mg/100 g d.m. for LV, RW, VIN, VIC, DK, and WW, respectively). The new developed method was validated for specifi city, repeatability, and accuracy and can be suitable for routine quality and quantity analysis of dietary supplements containing grape vine (Vitis vinifera).

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