• Natural Product Sciences
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• v.7 no.3
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• pp.68-71
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• 2001

The phytochemical investigation of Halocharis hispida revealed the presence of 1-heptatriacontanol, ${\beta}-sitosterol$, ${\beta}-sitosterol-3-O-glucoside$, kaempferol, vitexin and isorhamnetin-3-O-galactoside in addition to vanillic, ferulic, isoferulic, syringic and caffeic acids. The different isolated compounds were identified by different physical, chemical, chromatographic and/or spectral methods.

• Communications for Statistical Applications and Methods
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• v.16 no.2
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• pp.389-396
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• 2009

Approximations for the null distribution of a test statistic arising in multivariate analysis to test homogeneity of variances and a mixture of two beta distributions by making use of a product of beta baseline density function and a polynomial adjustment, so called beta-polynomial density approximant, are discussed. Explicit representations of density and distribution approximants of interest in each case can easily be obtained. Beta-polynomial density approximants produce good approximation over the entire range of the test statistic and also accommodate even the bimodal distribution using an artificial example of a mixture of two beta distributions.

• Natural Product Sciences
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• v.11 no.2
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• pp.75-78
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• 2005

A new acetophenone named rumexin $(3-hydroxy-5-methyl-4-O-{\beta}-D-glucopyranosyl\;acetophenone)$ was isolated from methanolic extract of Rumex aquatica together with eight known compounds, $quercetin-3-O-{\beta}-D-glucuropyranoside$, $musizin-8-O-{\beta}-D-glucopyranoside$, $quercetin-3-O-{\alpha}-L-rhamnoside$, $emodin-8-O-{\beta}- D-glucopyranoside$, caffeic acid, $1-O-caffeoyl-{\beta}-D-glucopyranoside$, 1-methyl caffeic acid, $kaempferol-3-O-{\beta}-D-glucuropyranoside$. All of the above compounds were isolated from Rumex aquatica for the first time, and structures of compounds were established by spectroscopic means.

• Natural Product Sciences
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• v.12 no.2
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• pp.89-93
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• 2006

One new sterol glucoside, $gomphsterol\;{\beta}-D-glucoside$ 1 along with known compounds, ${\beta}-sitosterol$, stigmasterol, campesterol, $stigmasterol-{\beta}-D-glucoside$, friedelin, 3-epi-friedelinol, allantoin, and $chrysoeriol-7-O-{\beta}-D-glucoside$ have been isolated from the aerial parts of Gomphrena globosa (Amaranthaceae). On the basis of spectroscopic (including 2D NMR) and chemical studies, the structure of 1 was elucidated as $(22E,24S)-24-ethylcholesta-7,9(11),22-trien-3{\beta}-ol-3-O-{\beta}-D-glucopyranoside$. Known compounds are reported for the first time from this plant species.

• Natural Product Sciences
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• v.17 no.1
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• pp.1-4
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• 2011

Chemical investigations of the stony coral Alveopora japonica Eguchi (Poritidae) resulted in the isolation of four known compounds (1 - 4). The structures of 1 - 4 were identified as a sterol, ergosta-5,24(28)-dien-$3{\beta}$-ol (1), a mixture of monoacyl glycrols (2), eicosanoic acid and tetracosanoic acid, and two nucleosides, thymine (3) and 2'-deoxythymidine (4), respectively, on the basis of spectroscopic and physicochemical analyses including 1D- and 2D- NMR techniques as well as by comparison of their data with the published values. Compounds 1 - 4 were isolated from this species for the first time. Moreover, these compounds (1 - 4) were found in the genus Alveopora and the family Poritidae for the first time.

• KSBB Journal
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• v.11 no.4
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• pp.411-419
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• 1996

In this research, an extractive production system for alkaloids, where production and some degree of separation occur simultaneously, was developed in a way that the fast removal of alkaloid produced from the suspension cultures was done by capturing alkaloid with cyclodextrins. The alkaloid production was substantially enhanced up to 40 fold when the solid cultures of E. califonica cells treated with ${\beta}$-cyclodextrin compared to the control. The enhancement of alkaloid production was also observed in the suspension cultures. Interestingly, the production pattern seemed to change when the cultures were treated with ${\beta}$-cyclodextrin so that the major part of the alkaloids in the treated cultures was present in the medium, while the non-treated cultures produced the alkaloids intracellularly. ${\beta}$-cyclodextrin was the most effective one in terms of the alkaloid production among the cyclodextrilns(${\alpha}$-cylodextrin, ${\beta}$-cyclodextrin and ${\gamma}$-cyclodextrin) tested in the suspension cultures. ${\beta}$-cyclodextrin showed no adverse effect on the cell growth. The most effective concentration of ${\beta}$-cyclodextrin was observed around 1.5% (w/v) in the suspension cultures. The formation of the inclusion complex of the alkaloids with ${\beta}$-cyclodextrin in the suspension cultures was confirmed by detecting the shift of UV absorbance from 274 nm to 282 nm with a UV spectrophotometer.

• Journal of Pharmaceutical Investigation
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• v.27 no.1
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• pp.29-38
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• 1997

Precipitation was formed during the preparation of decoction from a mixture of Scutellariae Radix and Coptidis Rhizoma. Baicalin and berberine were identified in this coprecipitated product (CPP) and these components were the active ingredients of two herbal medicine. We extracted respectively crude baicalin and berberine in Scutellariae Radix and Coptidis Rhizoma and prepared coprecipitate of crude baicalin-berberine. To increase the stability and bioavailability of coprecipitate of crude baicalin-berberine(CBB), which is slightly soluble drug, its inclusion complex was prepared and studied in this experiment. Inclusion complex of CBB with ${\beta}-cyclodextrin(CBB-{\beta}-CD)$ was prepared by freeze drying method and its characteristics were ascertained by means of solubility test, differential thermal analysis(DTA) and scanning electron microscope(SEM). The type of $CBB-{\beta}-CD$ is classified as $A_L-type$ on phase solubility diagram, and the stoichiometric ratio of CBB(baicalin in CBB) : ${\beta}-CD$ complex is 1:1 and formation constant is 151 $M^-1$. The solubility, dissolution, in situ absorption and serum concentration of $CBB-{\beta}-CD$ were significantly increased when compared to CBB. Therefore enhanced bioavailability of CBB by inclusion complexation with ${\beta}-cyclodextrin$ might be useful for dosage form design of active ingredients of two herbal medicine.

• Food Engineering Progress
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• v.15 no.3
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• pp.214-220
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• 2011

$\beta$-Glucosidase enzyme reaction under high hydrostatic pressure was investigated in terms of physical chemistry. A model substrate (p-nitrophenyl-${\beta}$-D-glucopyranoside(pNPG)) was used, and the pressure effects on the enzymatic hydrolysis (pNPG${\rightarrow}$pNP) at 25 MPa, 50 MPa, 75 MPa, and 100 MPa were analyzed. Two parts of the reaction such as kinetic and equilibrium stages were considered for mathematical modelling, and their physicochemical parameters such as forward and inverse reaction constants, equilibrium constant, volume change by pressure, etc. were mathematically modeled. The product concentration increased with pressure, and the two stages of reaction were observed. Prediction models were derived to numerically compute the product concentrations according to reaction time over kinetic to equilibrium stages under high pressure condition. Conclusively, the $\beta$-Glucosidase enzyme reaction could be activated by pressurization within 100 MPa, and the developed models were very successful in their prediction.

• The Pure and Applied Mathematics
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• v.5 no.2
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• pp.123-132
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• 1998

Let F and G denote the distribution functions of the failure times and the censoring variables in a random censorship model. Susarla and Van Ryzin(1978) verified consistency of $F_{\alpha}$, he NPBE of F with respect to the Dirichlet process prior D($\alpha$), in which they assumed F and G are continuous. Assuming that A, the cumulative hazard function, is distributed according to a beta process with parameters c, $\alpha$, Hjort(1990) obtained the Bayes estimator $A_{c,\alpha}$ of A under a squared error loss function. By the theory of product-integral developed by Gill and Johansen(1990), the Bayes estimator $F_{c,\alpha}$ is recovered from $A_{c,\alpha}$. Continuity assumption on F and G is removed in our proof of the consistency of $A_{c,\alpha}$ and $F_{c,\alpha}$. Our result extends Susarla and Van Ryzin(1978) since a particular transform of a beta process is a Dirichlet process and the class of beta processes forms a much larger class than the class of Dirichlet processes.

• Journal of the Korean Applied Science and Technology
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• v.16 no.2
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• pp.117-125
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• 1999

The alkylation benzene with 1-dodecene of Mordenite, Zeolite ${\beta}$ and Zeolite Y was studied in the stirring batch reactor. The kinds of zeolites were found to have influenced the reaction conversion and distribution of phenyldodecane isomer in the product. Compared to the alkylation conducted over Zeolite Y and Zeolite ${\beta}$, the alkylation over Mordenite exhibited higher distribution of 2-phenyldodecane and the alkylation conducted over Zeolite Y and Mordenite, the alkylation over Zeolite ${\beta}$ exhibited higher distribution of heavy alkylate which formed through oligomerization reaction readily deactivated the Lewis acid sites. A special feature of the effect of the benzene to 1-dodecene ratio the reaction conversion and selectivity of phenyldodecane isomer was found. At alkylation of benzene with 1-dodecene over Zeolite ${\beta}$, when the catalyst content in the system was high, the reaction will reach the optimal conversion at the higher B/D. When the benzene to 1-dodecene ratio was high, the selectivity of phenyldodecane isomer is high. It was also found that at the similar reaction conversion there was the same product distribution regardless of D/C ratio.