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11.
Naruse K Quan YS Choi SM Park CS Jin DI 《The Journal of reproduction and development》2007,53(3):679-684
This study was carried out to investigate the effects of minimum essential medium (MEM) vitamins during in vitro maturation (IVM)/in vitro culture (IVC) of porcine nuclear transfer (NT) embryos on subsequent developmental capacity in vitro. Porcine cumulus-oocyte complexes (COCs) were divided into five groups, matured for 44 h in maturation medium with various concentrations of MEM vitamins (0, 0.05, 0.1, 0.2 and 0.4%), and observed for maturation rate. Also, COCs were matured in NUSU-23 media without MEM vitamins for 44 h and cultured in PZM-3 media with various concentrations of MEM vitamins (0, 0.05, 0.4 and 1.0%) for 6 days following nuclear transfer. Factorial (IVM/IVC) experiments were also performed in NCSU-23 medium with or without 0.05% MEM vitamins and PZM-3 medium with or without 0.4% MEM vitamins. They were then tested by examining in vitro development of the porcine reconstructed embryos. The maturation rates of the COCs treated with the MEM vitamins did not differ significantly among the MEM vitamin-treated groups. Addition of vitamins to culture medium did not affect development of porcine reconstructed embryos in vitro. However, addition of low concentrations of MEM vitamins only to maturation medium increased (P<0.05) the proportion of NT embryos developing into blastocysts compared with the control group. Addition of MEM vitamins to IVC medium did not enhance the developmental rate compared with the control group. Thus, addition of MEM vitamins to IVM medium could improve subsequent blastocyst development of porcine NT embryos. 相似文献
12.
Electron spin resonance (ESR) spectroscopy and near-infrared (NIR) fluorescence spectroscopy were performed to observe singlet oxygen quenching by resveratrol. Resveratrol greatly decreased the 2,2,6,6-Tetramethyl-4-piperidone-N-oxyl radical signal as determined by ESR spectroscopy. Resveratrol also efficiently decreased luminescence emission at 1268 nm as studied with a NIR spectrofluorometer, showing positive evidence of singlet oxygen quenching by resveratrol. The total singlet oxygen quenching rate constant (kr+kq) of resveratrol in methanol was determined to be 2.55×10(7) M(-1) s(-1). The singlet oxygen chemical quenching rate constant (kr) of resveratrol was calculated by measuring its reaction rate with singlet oxygen relative to that of α-terpinene in the same solution under light illumination. The kr value of resveratrol was 1.15×10(6) M(-1) s(-1). The percent partition of chemical quenching over total singlet oxygen quenching (kr×100)/(kr+kq) for resveratrol was 5.11%. The results showed that resveratrol quenches singlet oxygen almost exclusively through the mechanism of physical quenching. Resveratrol showed a protective activity similar to that of BHA on the methylene blue sensitized photooxidation of α-terpinene. This unambiguously explains the mechanism of how resveratrol protects tissues and cells in biological systems or important nutrients in food systems against their photosensitized oxidations. 相似文献
13.
Udomsil N Rodtong S Choi YJ Hua Y Yongsawatdigul J 《Journal of agricultural and food chemistry》2011,59(15):8401-8408
The potential of Tetragenococcus halophilus as a starter culture for flavor improvement in fish sauce fermentation was elucidated. Four strains of T. halophilus isolated from fish sauce mashes were inoculated to anchovy mixed with 25% NaCl with an approximate cell count of 10(6) CFU/mL. The α-amino content of 6-month-old fish sauce samples inoculated with T. halophilus was 780-784 mM. The addition of T. halophilus MRC10-1-3 and T. halophilus MCD10-5-10 resulted in a reduction of histamine (P < 0.05). Fish sauce inoculated with T. halophilus showed high contents of total amino acids with predominantly high glutamic acid. Major volatile compounds in fish sauce were 2-methylpropanal, 2-methylbutanal, 3-methylbutanal, and benzaldehyde. T. halophilus-inoculated fish sauce samples demonstrated the ability to reduce dimethyl disulfide, a compound contributing to a fecal note. The use of T. halophilus for fish sauce fermentation improves amino acid profiles and volatile compounds as well as reduces biogenic amine content of a fish sauce product. 相似文献
14.
Utilization of biochar impregnated with anaerobically digested slurry as slow‐release fertilizer
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We examined the possibility of an environment‐friendly slow‐release fertilizer (SRF) made of biochar impregnated by anaerobically digested slurry. The biochar materials were produced from three types of feedstocks (orange peel, residual wood, water‐treatment sludge) at different temperatures of 300°C, 500°C, and 700°C via pyrolysis. The release behaviors of the water‐soluble K+, Ca2+, and Mg2+ were similar for all impregnated biochars and the commercial SRF used. The water‐retention capacity was greatly improved by mixing the biochar‐SRF with the soil. The yield of lettuce was lower for the biochar‐SRF applications of 3.7 to 34.2 t ha–1 than for the commercial SRF application of 51.4 t ha–1. This might be due to excessive increase of soil pH for the biochar‐SRF application. Based on these results, the authors concluded that the biochar impregnated with nutrients could become an effective slow‐release K+ fertilizer. 相似文献
15.
A Laboratory Column Study on the Biodegradation of Toluene and Methyl tert–Butyl Ether: The Effect of Substrate Interactions 总被引:1,自引:0,他引:1
Chung Seung-Gun Kim Dong-Ju Lee Sang-Hyup Choi Jae-Woo 《Water, air, and soil pollution》2013,224(4):1-8
Soil vapor extraction (SVE) is one of the most effective remediation technologies for soil and groundwater contamination. Soil particles can be mobilized by air perturbation during SVE, resulting in the differentiation of porous media, which has not been well addressed. This paper developed a numerical method to study the flow pattern and quantify the change of porous media for the first time. Based on the mass equilibrium and Darcy’s law, a two-phase water–air flow model was constructed with integration of saturation, relative permeability, and capillary pressure during SVE. Relationship between porosity and saturation was deduced and coupled with the two-phase flow model for quantifying change of porous media in real time. Results reveal that both porosity and permeability increase sharply in the early stage of SVE then gradually to a quasi-steady state. These increases in vadose zone tapered off with distance from the SVE screen and the steady period occurred later as well. The influence radius of a single SVE well and the change degree in porosity and permeability of media were proportional to the extraction vacuum and the driving coefficient C, which is more sensitive than extraction vacuum according to the simulation results. Knowledge from this modeling exercise provides a useful tool to estimate the change of remediated zone and assess the environmental risk of remedial activities at real-world contamination sites. 相似文献
16.
Identification of a RAPD marker linked to a brown planthopper resistance gene in rice 总被引:12,自引:0,他引:12
We report the tagging of a brown planthopper (BPH) resistance gene (Bph–1) in rice using RAPD and RFLP markers. The Korean
rice variety ‘Gayabyeo’ has dominant duplicate genes including Bph–1 conferring resistance to biotype 1 of BPH. Bulked segregant
RAPD analysis was employed for rapid identification of DNA markers linked to resistance genes. For tagging these two genes,
an F2F3 population from a ‘Gayabyeo’ × ‘Nagdongbyeo’ cross was developed and evaluated for BPH resistance. Three bulked DNAs
from two groups of homozygous BPH resistant (each for Bph–1 and the other unknown gene) and homozygous susceptible F2 plants
were analyzed by RAPD using 140 random oligomers. One primer, OPD–7 yielded a 700-bp fragment that was present in Gayabyeo
and resistant F2 plants (homozygous for Bph-1 locus) but absent in Nagdongbyeo and susceptible F2 plants. Cosegregation of
this marker with Bph-1 was verified using an F2 population segregating for Bph-1. Chromosomal regions surrounding the Bph-1
were examined with additional RFLP and microsatellite markers on chromosome 12 to define the location of the RAPD marker and
Bph-1. Use of this RAPD marker could facilitate early selection of resistant lines for BPH.
This revised version was published online in July 2006 with corrections to the Cover Date. 相似文献
17.
Sung-Je Choi Eun-Jeong Park Hirotoshi Endo Yukihiro Kitade Naotsune Saga 《Fisheries Science》2008,74(4):822-829
ABSTRACT: To investigate inheritance of chloroplasts and mitochondria (organelles) in the marine red alga Porphyra yezoensis , cleaved amplified polymorphic sequence (CAPS) profiles of the two strains, TU-2 and KGJ, as parental gametophytes and 44 hybrid sporophytes (i.e. female of TU-2 and male of KGJ) were examined. A carbamyl phosphate synthase small subunit gene ( carA ) and ribosomal protein S11 gene ( rps11 )-small subunit ribosomal RNA gene ( rns ) spacer region were used as molecular markers for the chloroplast and mitochondrial DNAs, respectively. Thirty-eight of 44 (86.4%) conchocelis colonies showed maternal banding patterns, five (11.4%) colonies showed biparental bands and one (2.2%) colony showed paternal bands in CAPS analyses both with chloroplast and mitochondrial markers. These results suggest that organelles of P. yezoensis are inherited uniparentally from the female parent. 相似文献
18.
ABSTRACT: As part of this study on the isolation of cholinesterase inhibitors from natural marine products, the bioactivity of the ethanolic extracts from 27 Korean seaweeds were screened using acetylcholinesterase (AChE) and butyrylcholinesterase (BChE) inhibitory assays. Ecklonia stolonifera exhibited promising inhibitory properties against both AChE and BChE. Bioassay-guided fractionation of the active n -hexane and ethyl acetate (EtOAc) soluble fractions, obtained from the ethanolic extract of E. stolonifera , resulted in the isolation of the sterols; fucosterol ( 1 ) and 24-hydroperoxy 24-vinylcholesterol ( 2 ), from the n -hexane fraction and the phlorotannins; phloroglucinol ( 3 ), eckstolonol ( 4 ), eckol ( 5 ), phlorofucofuroeckol-A ( 6 ), dieckol ( 7 ), triphlorethol-A ( 8 ), 2-phloroeckol ( 9 ) and 7-phloroeckol ( 10 ), from the EtOAc fraction. Of these, compounds 2 , 9 and 10 were isolated from E. stolonifera for the first time. Compounds 4 – 7 , 9 and 10 exhibited inhibitory potential against AChE, with 50% inhibition concentration (IC50 ) values of 42.66 ± 8.48, 20.56 ± 5.61, 4.89 ± 2.28, 17.11 ± 3.24, 38.13 ± 4.95 and 21.11 ± 4.16 μM, respectively; whereas, compounds 1 , 2 , 4 and 6 were found to be active against BChE, with IC50 values of 421.72 ± 1.43, 176.46 ± 2.51, 230.27 ± 3.52 and 136.71 ± 3.33 μM, respectively. It has been suggested that the inhibition of these enzymes by the sterols and phlorotannins derived from marine brown algae could be a useful approach for the treatment of Alzheimer's disease. 相似文献
19.
Recycled polyols from waste polyurethane (PU) foams were grafted onto PU to improve the properties such as tensile strength, shape recovery, low-temperature flexibility, and water compatibility. The recycled polyol was either purified by column chromatography before grafting or was used directly for grafting. The soft segment melting temperature of PU did not notably increase with the addition of polyol, whereas the glass transition temperature increased with increased polyol content. The tensile strength sharply increased at low polyol content and decreased at high polyol content, while the strain at break did not significantly change with an increase in polyol content. The shape recovery at 10 oC notably improved compared with unmodified PU and remained high after four cyclic tests. Polyol-grafted PU demonstrated better lowtemperature flexibility and reduced the water vapor permeability of PU membranes. Overall, grafting recycled polyol onto PU significantly improved the tensile stress, shape recovery, and low-temperature flexibility of PU. 相似文献
20.
Byoung-Min Lee Joon-Pyo Jeun Phil-Hyun Kang Jae-Hak Choi Sung-Kwon Hong 《Fibers and Polymers》2017,18(2):272-277
Nanocrytalline cellulose (NCC) was isolated using cellulose extracted from two different precursor materials: Eucalyptus globulus and rice straw. The two ground precursor materials were autoclaved with a 10 % NaOH solution at 120 °C for 3 h. The alkali-treated precursor materials were bleached using sodium chlorite/acetic acid and sodium hypochlorite. The bleached precursor materials were acid-hydrolyzed in 65 % (w/w) sulfuric acid at 45 °C for 30-120 min. The changes in the chemical composition of the two precursor materials were studied before and after bleaching by Fourier transform infrared spectroscopy according to the NREL report and TAPPI standards. Hydrolyzates were characterized by X-ray diffractometry, thermogravimetric analysis, Zeta-potential analysis, and transmission electron microscopy. The results revealed that the physical properties of NCC were strongly dependent on the acid-hydrolysis time. 相似文献