• Journal of Food Hygiene and Safety
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• v.11 no.2
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• pp.149-157
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• 1996

A procedure for the determination of Aflatoxins in food and grains which utilizes reversed phased liquid chromatographic (LC) analysis with postcolumn derivatization by an electrochemical cell and determination with a fluorescence detector has been evaluated. The LC mobile phase was water-acetonitrile-methanol (6+2+2) with 1mM KBr and 1 mM HNO3 which gave baseline separation for the four Aflatoxins (AfB1, AfB2, AfG1, AfG2). The electrochemical cell set at 7V, generated bromine and derivatized aflatoxins B1 and G1, The derivatives were detected by the fluorescence detector. The aflatoxins in naturally contaminated corn samples were isolated by three different cleanup procedures: the AOAC method I column(CB method), a rapid filtrate column (Romer's column), and an immunoaffinity column. The final extract were quantitated with fluordensitometric TLC and the LC postcolumn derivatization techniques. The results were quite similar, however the LC technique showed less interferences and could be automated. Samples of corn, raw peanuts, peanut butter and dried dates were also analyzed successfully with this procedure.

• Biotechnology and Bioprocess Engineering:BBE
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• v.5 no.1
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• pp.13-16
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• 2000

Simple procedures have been devised for purifying recombinant human interleukin-2 (hIL-2), which was expressed in Escberichia coli using sequences of glucagon molecules and enterokinase cleavage site as an N-terminus fusion partner. The insoluble aggregates of recombinant fusion protein produced in E. coli cytoplasm were easily dissolved by simple alkaline pH shift $(8\rightarrow12\rightarrow8)$. Following enterokinase cleavage, the recombinant hIL-2 was finally purified by one-step reversed-phase HPLC with high purity. The ease and high efficiency of this simple purification process seem to mainly result from the role of used glucagon fusion partner, which could be applied to the production of other therapeutically important proteins.

• Structural Engineering and Mechanics
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• v.75 no.2
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• pp.145-155
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• 2020

This paper investigates the influence of spatial varations of accidental mass eccentricities on the torsional response of inelastic multistorey reinforced concrete buildings. It complements recent studies on the elastic response of structural buildings and extends the investigation into the inelastic range, with the aim of providing guidelines for minimising the torsional response of structural buildings. Four spatial mass eccentricity configurations of common nine story buildings, along with their reversed mass eccentricities subjected to the Erzincan-1992 and Kobe-1995 ground motions were investigated, and the results are discussed in the context of the structural response of the no eccentricity models. It is demonstrated that when the initial linear response is practically translational, it is maintained into the inelastic phase of deformation as long as the strength assignment of the lateral resisting bents is based on a planar static analysis where the applied lateral loads simulate the first mode of vibration of the uncoupled structure.

• Asian-Australasian Journal of Animal Sciences
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• v.14 no.11
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• pp.1505-1510
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• 2001

A method for mapping quantitative trait loci (QTL) was introduced incorporating the information of mixed progeny from complex pedigrees. The method consisted of two steps based on single marker analysis. The first step was to examine the marker-trait association with a mixed model considering common environmental effect and reversed QTL-marker linkage phase. The second step was to estimate QTL effects by a weighted least square analysis. A simulation study indicated that the method incorporating mixed progeny from multiple generations improved the accuracy of QTL detection. The influence of within-genotype variance and recombination rate on QTL analysis was further examined. Detecting a QTL with a large within-genotype variance was more difficult than with a small within-genotype variance. Most of the significant marker-QTL association was detectable when the recombination rate was less than 15%.

• Journal of Microbiology and Biotechnology
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• v.20 no.3
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• pp.501-505
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• 2010

1-Acetyl-$\beta$-carboline was isolated as an anti-MRSA agent from the fermentation broth of a marine actinomycete isolated from marine sediment. The producing strain was identified to be Streptomyces sp. by phylogenetic analysis of the 16S rRNA gene sequence. The anti-MRSA agent was isolated by bioactivity-guided fractionation of the culture extract by solvent partitioning, ODS open flash chromatography, and purification with a reversed-phase HPLC. Its structure was elucidated by extensive 2D NMR and mass spectral analyses. Combination of 1-acetyl-$\beta$-carboline with ampicillin exhibited synergistic antibacterial activity against MRSA.

• Biomolecules & Therapeutics
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• v.6 no.3
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• pp.256-260
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• 1998

-7-o-p-Fluorobenzoylchrysin was synthesized by condensing p-flouorbenzoic acid with chrysin in organic solvent, and its structure was identified by NMR, MS, UV, and IR. We also investigated the physicochemical properties, hypoglycemic effect, and the quantitative analysis method of this compound. The correlation coefficient of calibration curve on this compound was approximately 0.9945 by absorption spectrophotometry and 0.9989 by high perfornance liqid chromatography 7-o-p-Fluorobenzoylchrysin was resolved in 6.014 min by reversed-phase HPLC column with solvents consisting of methanol (80%) and 10mM phosphoric acd. Its blood glucose inhibition rate is 20.7%.

• Food Science and Biotechnology
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• v.14 no.5
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• pp.581-585
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• 2005

The antimicrobial activity of partially purified enterocin K25, produced by Enterococcus sp. K25, was abolished by proteases such as pepsin and proteinase K. The bacteriocin was resistant to heat treatment at $75^{\circ}C$ for 15 min and lost 75% of its activity at $100^{\circ}C$ for 30 min. Enterocin K25 showed bactericidal mode of action against an indicator strain, Lactobacillus plantarum NCDO 955. Enterocin K25 was purified to 112.6-fold purity via conventional steps of ammonium sulfate precipitation, ion exchange chromatography, and reversed phase high performance liquid chromatography (RP-HPLC). The molecular mass of the purified enterocin K25 was estimated as 4.3 kDa on an electrophoresis gel. Plasmid (${\sim}6.5\;kb$) linkage of production of enterocin K25 was confirmed by plasmid curing.

• The Korean Journal of Food And Nutrition
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• v.4 no.2
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• pp.161-166
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• 1991

The blocked N-terminus and N-terminal sequence of soybean B-amylase were aetermined by analyzing the acidic peptides derived on peptic digestion of the enzyme. The acidic peptides were separated from the digest on a Dowex 50$\times$2 column(1X5cm) and purified by reversed phase-high performance liquid chromatography(RP-HPLC). The major acidic peptide, PEP-1, was a heptapeptlde. The N-terminal 7 amino acid sequence of soybean B-amylase was deduced to be acetyl-Ala-Thf-Ser-Asp-Ser-Asn-Met- from the results of sequence analysis of PEP-1 and amino acid analysis of other acidic peptides.

• Korean Journal of Pharmacognosy
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• v.24 no.1
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• pp.47-53
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• 1993

The seasonal variations of the major six flavonol glycosides(kaempferol 2,6-dirhamnosyl glucoside, quercetin 3-O-rutinoside, kaempferol 3-O-rutinoside, isorhamnetin 3-O-rutinoside, quercetin 3-O-coumaroyl glucorhamnoside and kaempferol 3-O-coumaroyl glucorhamnoside) in Ginkgo biloba leaves were investigated. The contents were determined by HPLC on reversed phase $C_{18}$ column. This result showed that the percentage of six flavonol glycosides decreased during the season from 1.57% in May to 0.39% in November. The content of each flavonol glycoside indicated a similar tendency to decrease. However, the contents of rutinosides of kaempferol, quercetin and isorhamnetin fluctuated markedly than those of coumaroyl glucorhamnosides of kaempferol and quercetin and kaempferol 2,6-dirhamnosyl glucoside.

• Korean Journal of Pharmacognosy
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• v.24 no.1
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• pp.54-57
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• 1993

The seasonal variations of five biflavones from Ginkgo biloba leaves from May to November were investigated by a reversed phase HPLC method. The total amount of biflavones was increased with time to reach its maximum in yellow autumnal leaves. Each biflavone showed a similar tendency. It increased rapidly about 3.1-fold from May to June and thereafter gradually increased about 2.5-fold. The ratio of each biflavone content to the total amount of biflavones was in the order of as follows: isoginkgetin>sciadopitysin>bilobetin>ginkgetin>amentoflavone.