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Abstract  

A microcalorimetric technique based on the bacterial heat-output was explored to evaluate the effect of Mn(II) on Bacillus thuringiensis. The power-time curves of the growth metabolism of B. thuringiensis and the effect of Mn(II) on it were studied using an LKB-2277 BioActivity Monitor, ampoules method, at 28C. For evaluation of the results, the maximum peak-heat output power (P max) in the growth phase, the growth rate constants (k), the log phase heat effects (Q log ), and the total heat effect in 23 h (Q T) for B. thuringiensis were determined. Manganese has been regarded as the essential biological trace element. Mn(II) of different concentration have different effects on B. thuringiensis growth metabolism. High concentration (800-1600 μg mL-1) of Mn(II) can promote the growth of B. thuringiensis; low concentration (500-800 μg mL-1) can inhabit its growth.

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Summary

Chestnut exhibits anti-inflammatory, styptic, anti-diarrhea, and analgestic effects as a traditional Chinese medicine. There is increasing evidence that shows that the consumption of chestnuts has become more important in human nutrition due to the health benefits provided by the antioxidants. The phenolic compounds are responsible for major bioactivities, such as anti-tumor and anti-oxidation. A high-performance liquid chromatography (HPLC) method with diode array detection (DAD) was established for the simultaneous determination of six phenolic compounds (gallic acid, GA; protocatechuic acid, PR; catechin, CA; epicatechin, EP; quercetin, QU; kaempferol, KA) in Chinese chestnut (Castanea mollissima blume) kernel. The sample followed by separation on Eclipse XDB-C18 column (150 × 4.6 mm, id., 5 μm) with gradient elution of methanol-1.0% acetate acid solution as a mobile phase, at a temperature of 30°C, under the ratio of 1.2 mL min−1, with 5 μL injection volume, and multi-wavelength synthesis was used with DAD. The correlation coefficients were larger than 0.999, the recoveries were 97.58% for GA, 100.41% for PA, 96.23% for CA, 101.38% for QU, 99.15% for EP, and 98.60% for KA, relative standard deviation (RSD) were 1.04% for GA, 1.21% for PA, 1.09% for CA, 1.19% for QU, 1.06% for EP, and 1.20% for KA. This method was applied for the determination of phenolics in chestnut kernel and was found to be fast, sensitive, and suitable.

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Seven compounds, including two flavanones, dihydrokaempferol (1) and naringenin (2), and five terpenoids, boscartol A (3), 3,7-dioxo-tirucalla-8,24-dien-21-oic acid (4), 3α-acetoxyl-7-oxo-tirucalla-8,24-dien-21-oic acid (5), 11-keto-β-boswellic acid (6), and acetyl-11-keto-boswellic acid (7), have been purified by high-speed counter-current chromatography (HSCCC) from olibanum. For the separation, from 250 mg of the crude extract, 3.1 mg of 1 (95.2% purity), 2.7 mg of 2 (96.1% purity), 9.1 mg of 3 (96.7% purity), 4.5 mg of 4 (95.3% purity), 5.4 mg of 5 (96.3% purity), 48.1 mg of 6 (96.8% purity), and 45.5 mg of 7 (98.1% purity) were obtained by HSCCC with petroleum ether–ethyl acetate–methanol–water (1:0.8:1.1:0.6, v/v). The structures of these seven compounds were elucidated by a combination of electrospray ionization mass spectrometry (ESI–MS) and extensive nuclear magnetic resonance (NMR) spectroscopic.

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This study was conducted to compare structural development and biochemical accumulation of waxy and non-waxy wheat (NW) caryopses. The caryopses’ microstructure of the waxy wheat (WW) and NW cultivars at different developmental stages were observed under light, fluorescence, and scanning electron microscope. The results were as follows: Compared with NW,WWhad a shorter maturation duration, which was reflected in several following characteristics. Programmed cell death of the pericarp began earlier, and the chlorophyll-containing layer in the pericarp was smaller. Vacuoles in chalazal cells accumulated more tannins at different developmental stages. Starch granules and protein bodies in the endosperm showed a higher accumulation level in developing caryopses, and aleurone cells were larger in size with larger numbers of aleurone grains. An analysis of the element content indicated that the mineral elements Mg, P, K, and Ca exhibited a higher content, while the heavy elements Cr, Cd, and Pb exhibited a lower content in the aleurone layer.

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Male sterile mutants play an important role in the utilisation of crop heterosis. Male sterile plants were found in S5 generations of maize hybrid ZH2, through continuous sib-mating by using the fertile plants in the same population, we obtained a male sterile sibling population K932MS including sterile plants K932S and a fertile plant K932F. The objective of this study was to clarify the genetic characterisation and abortion characteristics by nucleus and cytoplasm effect analyses, cytoplasm grouping, and cytological observation. The results showed that no difference was found between K932S and K932F in the vegetative growth stage, but K932S had no emerging anther or pollen grains. The segregation ratio of fertile plants to sterile plants was 1:1 in the sibling progenies, while it was 3:1 in self-crossing progenies of K932F. The sterility of K932S could be restored among reciprocal progenies when seven normal inbred lines were used as females respectively. The fertility expression of K932S crossed with 30 testers would be changed in different test-crosses and some backcross progenies. The C-type restorer Zifeng-1 (Rf4Rf4) was able to restore the fertility of K932S, and the specific PCR amplification bands of K932MS were consistent with CMSCMo17. The anther of K932S began abortion at dyad with its tapetum expanded radically and vacuolated: this induced abnormality in the shapes of both dyads and tetrads. The microspore could not develop normally, and then it collapsed and gradually disappeared. Hence, K932MS is a C-type cytoplasmic male sterile mutant with a pollen-free, stable inheritance: it has potential application value for further research.

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The aim of this study was to investigate postprandial effects of two Chinese liquors on s elected cardiovascular disease risk factors in humans. Sixteen healthy men were randomized into three groups in a three-way crossover study: tea-flavor liquor (TFL), traditional Chinese liquor (TCL) and water control (WC). Every subject consumed 60 mL of either liquor (45% (v/v) ethanol) or water together with a high-fat meal, respectively. Compared with baseline, serum uric acid was significantly increased in TFL group (0.5-hour: P = 0.012; 1-hour: P = 0.001; 2-hour: P = 0.008) and it was significantly decreased in WC group (1-hour: P = 0.001; 2-hour: P = 0.001; 4-hour: P < 0.001), while uric acid was non-significantly increased in the TCL group. High-sensitive C-reactive protein (hs-CRP) was significantly increased in the TCL (P = 0.014) and WC (P = 0.008) groups at postprandial 4 hours compared with baseline. There was no significant difference between groups during the postprandial period for these two parameters or other biochemical parameters. In conclusion, both liquors increased postprandial uric acid, and no significant difference was observed for the effects of TFL and TCL on the measured biochemical parameters.

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The identification of the diversity of microscopic fungi of lithobiont communities of the Argentine Islands in specimens collected during the 22nd Ukrainian Antarctic Expedition was the purpose of this work. Samples of rock, soil, mosses and lichens of rock micro-habitats of “Crustose lichen sub-formation and fruticose lichen and moss cushion sub-formation” were used in the work. These samples were used for extracting and cultivation of filamentous fungi on dense nutrient media. Determination of physiological and biochemical characteristics and identification of yeast-like fungi were performed using a microbiological analyser ‘Vitek-2’ (‘Bio Merieux’, France). Cultivation of microorganisms was carried out at temperatures from +2 to +37 °C. In results cultures of microscopic fungi of Zygomycota (Mucor circinelloides), Ascomycota (species of the genera cf. Tlielebolus, Talaromyces), representatives of the Anamorphic fungi group (Geomyces pannorum, species of the genera Alternaria, Acremonium, Aspergillus, Penicillium, and Cladosporium) were isolated from Antarctic samples. Microscopic fungi Penicillium spp. were dominated after the frequency in the studied samples (54.5%). Rhodotorula rubra and Candida sp. among isolated yeast fungi, and dark pigmented fungi represented by Aureobasidium pulhdans and Exophiala spp. were identified. The biological properties of a number of isolated fungi (the potential ability to synthesise important biologically active substances: melanins, carotenoids, lipids) are characterised. Mycobiota of rock communities of Argentine Islands is rich on filamentous and yeast fungi similarly to other regions of Antarctica. A number of fungi investigated are potentially able to synthesise biologically active substances. The dark pigmented species of the genera Cladosporium, Exophiala, Aureobasidium pulhdans, capable of melanin synthesis; ‘red’ yeast Rhodotorula rubra (carotenoid producers and resistant to toxic metals); Mucor circinelloides and Geomyces pannorum, lipid producers, are among these fungi. Yeast-like fungi assimilated a wide range of carbohydrates, which will allow them to be further used for cultivation in laboratory and process conditions. The collection of technologically promising strains of microorganisms, part of the Culture Collection of Fungi at Taras Shevchenko National University of Kyiv (Ukraine), is updated with isolated species (strains) of filamentous fungi and yeast – potential producers of biologically active substances, obtained within this study.

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The aim of this study was to investigate the effects of maternal lead exposure on the learning and memory ability and expression of tau protein phosphorylation (P-tau) and beta amyloid protein (Aβ) in hippocampus of mice offspring. Pb exposure initiated from beginning of gestation to weaning. Pb acetate administered in drinking solutions was dissolved in distilled deionized water at the concentrations of 0.1%, 0.5% and 1% groups. On the 21 th of postnatal day, the learning and memory ability of the mouse pups was tested by Water Maze test and the Pb levels in blood and hippocampus of the offspring were also determined. The expression of P-tau and Aβ in hippocampus was measured by immunohistochemistry and Western blotting. The Pb levels in blood and hippocampus of all exposure groups were significantly higher than that of the control group ( P < 0.05). In Water Maze test, the performances of 0.5% and 1% groups were worse than that of the control group ( P < 0.05). The expression of P-tau and Aβ was increased in Pb exposed groups than that of the control group ( P < 0.05). Tau hyper-phosphorylation and Aβ increase in the hippocampus of pups may contribute to the impairment of learning and memory associated with maternal Pb exposure.

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Separation and analysis of water-soluble proteins (WSP) are important in understanding wheat grain proteome fundamentals. However, due to their high degree of heterogeneity and complexity in the compositions, separating WSP is generally difficult and relevant methodologies are not efficiently developed yet. Capillary electrophoresis (CE) is one of the analytical methods currently used for protein separation and characterization. In the present study, a CE method is established for rapidly separating and characterizing WSP of wheat grains. The established method was tested in various applications including wheat variety and germplasm identification as well as protein synthesis and accumulation studies during different grain development stages subject to genotypic and environmental variations. As results, the characteristic CE patterns of a range of bread wheat cultivars and related species were readily identified. The synthesis and accumulation patterns of wheat WSP during developing grains as well as their stabilities in different environments were also investigated. The technical advancements present in this article appear to be useful for wheat cultivar and germplasm identification as well as genetics and breeding research.

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