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21.
Hydrogenated soybean oil was obtained after 10 min of hydrogenation with 0.5% selective type Ni catalyst at 230 degrees C, a hydrogenation pressure of 0.049 MPa, and an agitation rate of 300 rpm. The conjugated linoleic acid isomers in the hydrogenated soybean oil were isolated by using a silver ion-impregnated HPLC. Gas chromatography-mass spectrometry of 4,4-dimethyloxazoline (DMOX) derivatives of the isolated conjugated linoleic acid isomers were carried out for the identification of their chemical structures. By interpreting the mass spectra of the DMOX derivatives of conjugated linoleic acid isomers isolated by silver ion-impregnated HPLC, 20 different conjugated linoleic acid isomers present in hydrogenated soybean oil were identified. This is the first report for the mass spectrometric identification of the conjugated linoleic acid isomers present in hydrogenated vegetable oil. 相似文献
22.
Nitis?MukhopadhyayEmail author Mun?S.?Son Yong?C.?Ko 《Journal of Agricultural, Biological & Environmental Statistics》2004,9(4):479-499
A horticulturist was considering the number of days (X) each variety took from planting seeds to reach the stage when the first bud appeared for three local marigold varieties.
The data X could be recorded with accuracy of one-half day. The primary interest was to estimate the maximum waiting time between “seeding”
and “first budding” among three varieties under consideration. It was thought that a 99% confidence interval with width one
day would suffice. The horticulturist felt comfortable to assume a normal distribution for the response variable. He provided
positive lower bounds for the variances which forced pilot sample sizes to become unequal. We are not aware of any existing
methodology with unequal pilot sample sizes that would readily apply here. Accordingly, a new two-stage sampling design was
developed and implemented. The gathered data validated all assumptions made during the course of this investigation. Important
exact as well as large-sample properties of the proposed methodology are highlighted (Theorem 1). This methodology is proven
to be theoretically superior (Theorem 2) to the existing methodology for large sample sizes provided that the pilot sizes
could be “chosen” equal. For the experimental data on hand, the superiority of the new methodology has also been indicated
(Section 4.3). The solution to the primary estimation problem ultimately led to a natural and yet nontraditional selection
problem involving identification of the “worst” marigold variety. For this selection problem, a practical approach is developed
(Section 4.4) for evaluating the associated probability of correctly selecting the worst marigold variety. 相似文献
23.
The effects of sulfur addition on the formation of conjugated linoleic acid (CLA) isomers were studied during the hydrogenation of soybean oil with a nonselective type nickel catalyst. Sulfur addition greatly promoted CLA formation in soybean oil during hydrogenation. As the amount of sulfur increased to a certain level, the maximal quantity of CLA in soybean oil during hydrogenation increased greatly. However, further increase in sulfur addition above the certain level decreased CLA formation. The optimal sulfur level for the promotion of CLA formation differed greatly with the amount of nickel used. It was of great interest to find that the optimal ratio of sulfur to nickel for the promotion of CLA formation was always 0.06:1, regardless of the nickel amount used. At the same ratio of sulfur to nickel, higher nickel content induced significantly higher production of CLA (p < 0.05). At the optimal sulfur to nickel ratio, an increase in the nickel amount from 0.05 to 0.15% produced approximately 1.5 times higher levels of CLA during hydrogenation under the tested conditions. The CLA isomer compositions were greatly affected by both sulfur addition and amounts of nickel used for treatment. This is the first report of the possibility that the total quantity of CLA and their isomer composition could be manipulated during hydrogenation by controlling the amounts of sulfur and nickel. 相似文献
24.
Gebremeskel Eshetu Kebede Chun Woo Lee Subong Park Mun Kwan Kim 《Fisheries Science》2018,84(6):939-952
We investigated the underwater shapes of trolling lines for the improvement of hairtail fishing efficiency. Two sets of experiments were carried out, one on a small scale, where flume tank tests of four models were scaled down by a ratio of 1:10 and trolled at different speeds, and another at full scale, comprising a survey on board a commercial fleet. In situ trials were conducted off the coast of Jeju Island, South Korea, at 33°27′57.528″N, 126°55′48.846″E, a potential fishing ground for hairtail fishing. The full-scale gear was set by altering sinker weights whilst changing the length of the warp line at different towing speeds. A dynamic method using a mass-spring technique and full-scale gear was developed. External and internal forces that govern the motion of the gear were considered. A non-linear differential equation of motion was developed, solved by a fourth-order Runge–Kutta method at a time step of 5?×?10?4 s for each trial. A static method was also developed using full-scale gear to predict the equilibrium gear configuration under all fishing conditions. The dynamic method better predicts the actual underwater performance of trolling line gear in real time. 相似文献
25.
Norihiko Tomooka Mun Sup Yoon Koji Doi Akito Kaga Duncan Vaughan 《Genetic Resources and Crop Evolution》2002,49(5):521-530
A representative set of germplasm of genusVigna subgenus Ceratotropis specieswas used to analyze genetic diversity using amplified fragment lengthpolymorphism (AFLP) methodology. The germplasm was selected based onmorphological diversity and geographic origin and includes 18 out of the 21species in the subgenus Ceratotropis. Genetic diversitywithin and between taxa was measured using information generated by AFLP bandpolymorphism from which Jaccard's similarity coefficient and nucleotidediversity were estimated. The data were also used to generate phenograms tovisualize relationships among analyzed accessions. All species in sectionsCeratotropis and Aconitifoliae arewell separated. However, most of the species in sectionAngulares show a high level of similarity suggesting a lowlevel of genetic differentiation. In section Angulares onespecies, V. trinervia, is welldifferentiated from the other species and represents a separate evolutionarybranch between section Ceratotropis and other species insection Angulares. The relationships between the newlydescribed species V. aridicola,V. exilis, V.nepalensis and V.tenuicaulis and other species in the subgenusCeratotropis are described for the first time based on AFLPdata. 相似文献
26.
The effects and mechanism of sesamol on the methylene blue- or chlorophyll-sensitized photo-oxidations of soybean oil have been studied. Sesamol showed strong antiphoto-oxidative activity in both methylene blue-and chlorophyll-sensitized photo-oxidations of soybean oil in a dose-dependent manner. The 1.0 x 10(-3) M sesamol treatments showed 84.7 and 43.4% inhibitions of methylene blue- and chlorophyll-sensitized photo-oxidations of soybean oil in methylene chloride. The antiphoto-oxidative activity of sesamol was comparable to that of delta-tocopherol in both methylene blue- and chlorophyll-sensitized photo-oxidations, at the same molar basis. Sesamol effectively inhibited rubrene oxidation with a chemical source of singlet oxygen in microemulsion, showing its strong singlet oxygen quenching ability. The results suggested that the antiphoto-oxidative activity of sesamol in the photo-oxidation of oil was, at least in part, due to its singlet oxygen scavenging activity. The singlet oxygen quenching rate constant (k(ox-Q) + k(q)) of sesamol was determined to be 1.9 +/- 0.3 x 10(7) M(-1) s(-1). This represents the first report on the antiphoto-oxidative activity of sesamol in the sensitized photo-oxidation of oil, and its bimolecular singlet oxygen quenching ability. 相似文献
27.
28.
Hot water extract (HWE) of Pinus radiata bark was separated into monomeric polyphenol (MPP), oligomeric proanthocyanidin (OPA), and polymeric proanthocyanidin (PPA)
fractions by monitored chromatography using a Sephadex LH 20 column and an UV detector at 250 nm. The effects of these fractions
on NIH/3T3 fibroblasts and B16 melanoma cells were examined by evaluating cell viability, melanogenesis (melanin content),
morphological changes, and tyrosinase inhibitory activity. The polyphenolic fractions had a proliferation effect on fibroblasts,
with cell growth increasing significantly (P < 0.01) even at the high concentration of 1250 μg/ml. At 125 μg/ml, HWE, MPP, and OPA had no effect on melanogenesis, whereas
PPA significantly upregulated melanogenesis (P < 0.05). Melanogenesis was significantly upregulated in melanoma cells treated with these fractions at the high concentration
of 600 μg/ml (P < 0.01). B16 melanoma cells cultured with the proanthocyanidin (PA)-rich fractions (HWE, OPA, and PPA) showed marked dendrite
retraction, leading to significant morphological transformation. OPA in particular showed colored adhesion on the surface
of melanoma cells. All four fractions significantly inhibited mushroom tyrosinase activity when compared to arbutin and ascorbic
acid 2-glucoside (P < 0.05). The tyrosinase inhibitory activity of OPA and PPA did not differ significantly (P = 0.11), indicating that the inhibitory effects had a low correlation with molecular weight distribution. The inhibition
kinetics of PPA determined using a Lineweaver-Burk plot indicated that PPA is a noncompetitive inhibitor of l-3,4-dihydroxyphenylalanine oxidation by mushroom tyrosinase. 相似文献
29.
Ghosal S Hemminger JC Bluhm H Mun BS Hebenstreit EL Ketteler G Ogletree DF Requejo FG Salmeron M 《Science (New York, N.Y.)》2005,307(5709):563-566
It has been suggested that enhanced anion concentrations at the liquid/vapor interface of airborne saline droplets are important to aerosol reactions in the atmosphere. We report ionic concentrations in the surface of such solutions. Using x-ray photoelectron spectroscopy operating at near ambient pressure, we have measured the composition of the liquid/vapor interface for deliquesced samples of potassium bromide and potassium iodide. In both cases, the surface composition of the saturated solution is enhanced in the halide anion compared with the bulk of the solution. The enhancement of anion concentration is more dramatic for the larger, more polarizable iodide anion. By varying photoelectron kinetic energies, we have obtained depth profiles of the liquid/vapor interface. Our results are in good qualitative agreement with classical molecular dynamics simulations. Quantitative comparison between the experiments and the simulations indicates that the experimental results exhibit more interface enhancement than predicted theoretically. 相似文献
30.
Byeong Joo Seo Mi Ran Mun Rejish Kumar V. J Chul-Joong Kim Insun Lee Young-Hyo Chang Yong-Ha Park 《Veterinary research communications》2010,34(4):323-333
Lactic acid producing bacterial strain Probio-16 was isolated from the swine excrements under anaerobic conditions and characterized
by morphology and biochemical characteristics. The strain was further identified by 16S rRNA gene sequencing and phylogeneitc
analysis. The antimicrobial activity of the strain was assayed by testing for growth inhibition of thirteen pathogenic microorganisms.
The strain was tested for antiviral activity against porcine rotavirus in vitro in African green monkey epithelial cell line
TF-104. Antibiotic susceptibility of the strain against 13 antibiotics was tested using disk diffusion method. Phenotypically
and through 16S rRNA gene sequences, Probio-16 was identified and named as Lactobacillus reuteri Probio-16. This strain was resistant to pH 2.0, 5% porcine bile and exhibited antimicrobial activity against all the thirteen
enteric bacterial pathogens tested. Probio-16 supernatant inhibited porcine rotavirus in vitro in TF-104 cell lines. Except
for erythromycin and penicillin G at a concentration of 4 μg/ml, Probio-16 showed resistance to all other thirteen antibiotics
tested. This study indicates L. reuteri Probio-16 as a novel strain with its tolerance to low pH and bile, antimicrobial activity, antibiotic resistance and antiviral
activity against rotavirus, and an ideal probiotic candidate for animal and human application after the proper in vivo experiments. 相似文献