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BACKGROUND: The effects of short‐term ultraviolet B (UV‐B) irradiation on sweet basil (Ocimum basilicum L. cv. Cinnamon) plants at the 3–4 leaf pair and flowering stages were examined in controlled environment growth chambers. Plants were exposed to 0 (reference), 2 and 4 kJ UV‐B m?2 day?1 over 7 days. RESULTS: Exposure of basil plants to supplementary UV‐B light resulted in increased assimilating leaf area, fresh biomass and dry biomass. Stimulation of physiological functions in young basil plants under either applied UV‐B dose resulted in increased total chlorophyll content but no marked variation in carotenoid content. At the flowering stage the chlorophyll and carotenoid contents of basil were affected by supplementary UV‐B radiation, decreasing with enhanced UV‐B exposure. Both total antioxidant activity (2,2‐diphenyl‐1‐picrylhydrazyl free radical assay) and total phenolic compound content were increased by UV‐B light supplementation. Young and mature basil plants differed in their ascorbic acid content, which was dependent on UV‐B dose and plant age. UV‐B radiation resulted in decreased nitrate content in young basil plants (3–4 leaf pair stage). CONCLUSION: These results indicate that the application of short‐exposure UV‐B radiation beneficially influenced both growth parameters and biochemical constituents in young and mature basil plants. © 2012 Society of Chemical Industry  相似文献   
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Summary Polymerization of 9-(2,3-epoxypropyl) carbazole (EPC) and 1,2-epoxy-6-(9-carbazolyl)-4-oxahexane (ECOH) with triphenylcarbenium hexachloroantimonate and triphenylcarbenium tetrafluoroborate have been studied by the microcalorimetric technique. Triphenylcarbenium salts have turn out to be more efficient catalyst for the polymerization of carbazolyl-containing epoxides than Lewis acids, giving high yields at low initial concentration of the catalyst. Using comparatively restricted conditions of reaction ([triphenylcarbenium saltyda]o0.02 mol/l t50° C) transition from the conventional active chain end mechanism to the activated monomer mechanism has been observed at a sufficiently high degree of conversion of monomer.  相似文献   
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Lupine has the potential to be a new domestic source of vegetable protein due to its comparable quality to the commonly used soy proteins. However, the bioprocessing that take place in the production of wheat bread with non‐conventional flours could play an important role. The wholemeal Lupinus angustifolius and Lupinus luteus flours were fermented by bacteriocin‐producing strain of Pediococcus acidilactici. The effect of lupine flour supplementation on wheat bread quality, sensory and safety criteria was studied. The lupine additives significantly decreased the quality of bread. The fermented L. luteus flour (10% of flour basis) had a slightly higher positive effect on the specific volume and crumb porosity (5.4%) and lowering of crumb hardness (9.5%) than those of L. angustifolius. In contrary, consumers rated higher for bread with L. angustifolius sourdough, which contributed to a stronger taste score. The levels of tyramine, histamine and putrescine (32.6–215.8, 20.8–96.7 and 33.7–195.2 mg kg?1, respectively) do not present a health risk for consumers due to their relatively low levels in lupine fermented products. Bioprocessing used for wheat bread production with lupine flour additives could improve the nutritional profile of bread without increasing the risk of biogenic amine formation.  相似文献   
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An extract of Achillea millefolium herb (YE) was investigated for antioxidant activity using chemical and biological assays. Qualitative and quantitative analysis of some major phenolics was carried out by HPLC. An on-line HPLC-DPPH assay showed that YE possesses significant antiradical activity which is due to the presence of active components amongst phenolic compounds. Furthermore, direct effects of YE and a mixture of its identified phenolic compounds (MPC) on isolated rat heart mitochondrial function were investigated. We found that YE in concentration-dependent manner induce a decrease in State 3 respiration rate without any changes in the integrity of inner mitochondrial membrane. Thus, pyruvate oxidation was affected only by the highest used YE concentrations; meanwhile succinate oxidation was reduced even at lower YE concentrations. MPC had no effect on mitochondrial State 3 respiration rate. Fluorimetric measurements demonstrated that YE at concentrations that had no effect on the State 3 respiration rate significantly decreased H2O2 production in mitochondria.  相似文献   
6.
The owner of a mobile telephone is exposed to radiation from both the mobile telephone and base stations. They are often installed on the roofs of residential buildings. The article deals with electromagnetic fields generated by mobile communication antennas in the residential area. Measurements of electrical strength, magnetic strength and the electromagnetic field energy flux density were performed and compared to the established hygiene norms. Tests were conducted in the near and far zones of the antenna, in residential premises located directly in front of antenna, within the main radiation lobe of the antenna.  相似文献   
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In this study, the model gel-type delivery system containing rice bran (RB), lingonberry (Vaccinium vitis-idaea L.) press cake (LPC) and thyme essential oil (Thymus vulgaris L.), was developed and evaluated by their texture, gelation rate and antioxidant activity changes during storage and simulated gastrointestinal digestion. For the structuring of the gel-type RB-LPC matrix, a high-intensity ultrasound (850 kHz; 1.3 W cm−2) treatment at 40 °C was applied. The release of total phenols and flavonoids was measured during digestion process by a spectrophotometric method and reversed-phase high-performance liquid chromatography (RP-HPLC), respectively. The contributions of xanthan and alginate as gelling agents to improve the stability of the gel texture protecting it from fast degradation under gastrointestinal digestion enable a controlled release of antioxidants, thus improving their biodistribution. Storage temperature influenced the reduction of antioxidant activity in gels depending on stabiliser used, with the lowest values from those with alginate when stored for 28 days at 4 °C. This knowledge can be used to facilitate the selection of the most appropriate plant polysaccharide-based delivery system for specific applications.  相似文献   
8.
The ethanol extracts of apple fruits harvested from the cultivars Aldas, Auksis, Ligol, and Lodel grown in Lithuania were analyzed by the high-performance liquid chromatography method. Chlorogenic acid was found to be a predominant component in the apple fruits of all the cultivars, except the cultivar Ligol. (–)-Epicatechin was the major compound in the ethanol extracts of apple fruits obtained from all the cultivars, while the amount of (+)–catechin was lower. The following quercetin glycosides were identified and quantified: hyperoside, isoquercitrin, avicularin, rutin, and quercitrin. Hyperoside was the major quercetin glycoside in apple fruits.  相似文献   
9.
The aim of this study was to assess the level of some phytochemicals in 19 raspberry cultivars grown in Lithuania. The content of total ellagic acid measured after 20 h acidic hydrolysis of investigated raspberry cultivars, varied from 119.8 (cv. ‘Pokusa’) to 323.5 mg/100 g (cv. ‘Bristol’). The content of total phenolics ranged from 278.6 (cv. ‘Pokusa’) to 714.7 mg/100 g (cv. ‘Bristol’). The total anthocyanins content varied from 2.1 (yellow cv. ‘Beglianka’) to 325.5 mg/100 g (black cv. ‘Bristol’). The radical scavenging capacity of the tested raspberry cultivars highly correlating with their total phenolics and total ellagic acid content (r = 0.90 and 0.92, respectively). The results of this study expand the knowledge about variation in the content of valuable bioactive compounds in raspberries and may help for the selection and validation of the most productive cultivars.  相似文献   
10.
A multisensory conversational learning facility is described which permits the visually handicapped to share the process and content of instruction of sighted persons. The blind student receives live or recorded audio and graphic instruction synchronously via his aural and tactile/kinesthetic senses. A novel kinesthetic terminal for the blind is described which permits ``visual' perception of kinetic graphics. In the classroom the blind student perceives blackboard graphics concurrently with the instructor's live presentation; in the self-instruction mode he connects to a remote bank of audiographic instructional materials and receives lessons via telephone through a combined audio/kinesthetic terminal. The conversational learning system which serves simultaneously varying numbers of blind and sighted learners is controlled by a mini-computer. Applications of the audio/kinesthetic terminal in education of sighted persons and in research on information processes of the blind are briefly noted.  相似文献   
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