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- Author or Editor: D. Wang x
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Genetic structure of 142 parent lines of sorghum [Sorghum bicolor (L.) Moench] was analyzed using model-based approach based on SSR markers. Forty-one selected from 103 SSR markers were used to analyze the parent lines, which generated 189 alleles revealed by each marker ranging from 2 to 11 with an average of 4.6 per marker. The polymorphic information content (PIC) value was 0.543 with a range of 0.089 to 0.850. All the parent lines were assigned to 7 subgroups, named Kafir, Kaoliang, Feterita, Shallu, Hegari, Milo and Durra. Parent lines without clear pedigree record were clustered into their corresponding groups, and genetic components of each line were estimated by Q-values. Information of this study would be useful for breeders to conclude their genetic background and select appropriate parents for germplasm improvement and hybrid breeding, and thus improve the efficiency of breeding programs.
Rice sheath blight, caused by Rhizoctonia solani, is the most serious disease in the southern rice producing regions of China. The use of resistant varieties is the most economic strategy to control the disease. In this paper, a seedling inoculation method was used to evaluate rice germplasm resources for resistance to sheath blight. A total of 363 rice varieties were evaluated with a set of R. solani isolates. The results indicated that the rice varieties generally lacked resistance to R. solani, and no highly resistant/immune (HR) variety was found. However, two varieties displayed clear resistance (R) and 37 showed moderate resistance (MR) to the fungus. Overall, hybrid rice varieties have better resistance than conventional rice varieties, and among hybrid rice varieties, those with the II-32A sterile line genetic background were the most resistant. The results also indicated significant interactions between rice varieties and pathogen isolates, suggesting that an understanding of local R. solani populations is needed when recommending varieties to local growers.
The present study was to evaluate the survival rate of free and encapsulated Bifidobacterium bifidum BB28 under simulated gastrointestinal conditions and its stability during storage. Results showed that non-microencapsulated Bifidobacterium bifidum BB28 was more susceptible to simulated gastrointestinal conditions than microencapsulated bacteria. Microencapsulated Bifidobacterium BB28 exhibited a lower population reduction than free cells during exposure to simulated gastrointestinal conditions, the viable count of monolayer microcapsules, double layer microcapsules, and triple layer microcapsules decreased by nine magnitudes, four magnitudes, and one magnitude after 2 h, respectively. The enteric test showed that the microorganism cells were released from the monolayer, double layer, and triple layer microcapsules completely in 40 min. Moreover, the optimum storage times of free Bifidobacterium BB28, monolayer microcapsules, double layer microcapsules, and triple layer microcapsules were 21 days, 21 days, 28 days, and more than 35 days in orange juice, pure milk, and nutrition Express (a commercially available milk based drink), and the viable counts were maintained at 1×106 CFU g−1 or more, which means that the double layer and triple layer of microcapsules of B. bifidum BB28 have great potential in food application.
Five giant embryo mutants, described as MH-gel, MH-ge2, MH-ge3, MH-ge4 and MH-ge5 , which were derived from the same indica rice cv . ‘Minghui 86’ and characterized by 2.0, 1.88, 2.08, 1.93 and 1.88 times enlarged embryo than that of wild type, were selected for the current study. The mutated giant embryos were controlled by a single recessive gene, and except mutated locus with MH-ge1 other four loci were allelic to each other and the previous reported locus ge in japonica rice cv . ‘Kinmaze’. No obvious differences in physicochemical properties such as apparent amylose content (AAC), alkali spreading value (ASV), gel consistency (GC), and starch paste viscosity were observed between giant embryo mutants and wild type. Significant increases in the contents of crude lipid (LC), crude protein (PC), Vitamin B1 (V B1 ), Vitamin B2 (V B2 ), Vitamin E (V E ), essential amino acids such as Arginine (Arg), Aspartic acid (Asp), Glutamic acid (Glu), Lysine (Lys), Methionine (Met), and mineral elements such as calcium (Ca), iron (Fe), potassium (K), phosphorus (P) and zinc (Zn) were detected in brown rice (BR) of giant embryo mutants. The amounts of gamma aminobutyric acid (GABA), an inhibitory neurotransmitter, were similar in the BR of giant embryo mutants and wild type, and more GABA content was observed in germinated brown rice (GBR) than BR. Significant enrichments were detected in the GBR of giant embryo mutants, basically corresponding to the enlarged embryo.
Summary
A new HPLC method has been established for determination of 3-monoiodotyrosine (MIT), 3,5-diiodotyrosine (DIT), 3,5-diiodothyronine (T2), 3,3′,5-triiodothyronine (T3), 3,3′,5′-triiodothyronine (rT3), and thyroxine (T4) produced by hydrolysis of iodinated casein with barium hydroxide. The hydrolytic stability of each analyte was evaluated. Iodinated casein was hydrolyzed with saturated barium hydroxide solution for 16 h at 110°C and the barium ions were then removed as barium sulfate. Reversed-phase HPLC was performed on a 2.1 mm × 150 mm, 5 μm particle, C18 column with a mixture of acetonitrile and 0.1% (v/v) formic acid as mobile phase at a flow rate of 0.2 mL min–1. Acetonitrile was maintained at 5% (v/v) for 5 min and then increased linearly to 50% (v/v) within 35 min. All analytes were quantified by measuring the absorbance at 280 nm. Validation data indicated the method was linear, with regression coefficients (R 2) > 0.998, in the concentration ranges investigated. Sensitivity was adequate—limits of detection (LOD) were 0.04–0.38 μg mL–1 and limits of quantification (LOQ) were 0.05–0.38 μg mL–1. Accuracy and precision were acceptable — for all the analytes recovery was 82.0–93.0% and repeatability, as relative standard deviation, was 1.0–3.0%. Hydrolytic stability tests indicated MIT and DIT are much more stable than the other analytes. rT3 was not released directly from iodinated casein but was formed by deiodination of T4 during hydrolysis. The method could be used to identify iodinated casein, to evaluate its activity and quality, and for supervision and regulation of feed additives.
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.
Abstract
Radiolabeled somatostatin analogue is a useful ligand for scintigraphic imaging of somatostatin receptor-bearing tumors. In this study, we investigated the effects of different radiolabeling conditions on labeling yield and ratio between mono-iodinated and di-iodinated125I-Tyr3-octreotide by HPLC analysis. In vitro and in vivo stabilities of125I-Tyr3-octreotide and111In-DTPA-D-Phe1-octreotide were also determined. Both radiolabeled compounds were relatively stable in vitro, but were decomposed to free125I− and111In-DTPA in vivo, respectively.
Abstract
The behavior of153Sm-EDTMP in vitro and vivo is analyzed by the size exclusion HPLC. The experimental results show that EDTMP amounts have an obvious effect on the stability in vitro and uptake of153Sm-EDTMP in the liver. HPLC analysis of urine sample indicates that153Sm-EDTMP es excreted in the original form. The behavior in vivo of153Sm-EDTMP containing 4 μg is similar to that of153Sm-EDTMP containing 50 μg EDTMP at 1 h post-injection.
Abstract
DTPA-Octreotide(Pentetreotide), a somatostatin analogue which can bind specifically and with high affinity to somatostatin receptor in vitro and vivo, labeled with99mTc by tin reduction in acetate buffer, has been characterized by Reverse-phase High performance Liquid Chromatography. The effect of different solvents, mobile phase pH, linear gradient and the injected volume on the separation efficiency was evaluated. The results show that the separation efficiency is best using μBondapak-C18 (300×3.9 mm2), linear gradient of 40% to 80% methanol (1.0 ml/min) in 0.05M acetate buffer (pH 5.5) over a 30 min period and maintaining for another 10 min. The labeled product is a mixture which mainly consists of five components (a, b, c, d, e) successfully proved by HPLC. Paper chromatography is also evaluated in this paper. It may be used to determine the radiochemical purity of the labeling product, but is not a good choice for the verification each components.
Abstract
Fe–B ultrafine amorphous alloy particles (UFAAP) were prepared by chemical reduction of Fe3+ with NaBHO4 and confirmed to be ultrafine amorphous particles by transmission electron microscopy and X-ray diffraction. The specific heat of the sample was measured by a high precision adiabatic calorimeter, and a differential scanning calorimeter was used for thermal stability analysis. A topological structure of Fe-B atoms is proposed to explain two crystallization peaks and a melting peak observed at T=600, 868 and 1645 K, respectively.
