• Proceedings of the Korean Society for Agricultural Machinery Conference
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• 2000.11a
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• pp.76-100
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• 2000

A brief general discussion of the nature and function of biosensors is presented. While the primary motivator for biosensor development has been the health-care industries, recent research efforts have spread to problems in agriculture and biological production systems. To illustrate some of the research from our laboratory, three example biosensors and their corresponding applications are presented. The first of these is an immunosensor for measurement of the hormone progesterone during milking as a method to improve reproductive management of dairy herds. The second example is an enzyme sensor for measurement of urea in milk as a menas to determine the efficiency of conversion of input protein to milk protein and, thus, improve nutritional management of dairy herds. The third example is a DNA sensor using polymerase chain reaction to detect pathogenic bacteria in the wash water of fresh and minimally processed fruits and vegetables. The potential for application of biosensors in agriculture, agrobiotechnology, food processing, and environmental monitoring has barely been realized.

• The Journal of Internal Korean Medicine
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• v.30 no.2
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• pp.327-337
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• 2009

Objective : In benign prostatic hyperplasia, dihydrotestosterone acts as a potent cellular androgen and promotes prostate growth. Inhibiting enzyme 5${\alpha}$-reductase, which is involved in the conversion of testosterone to the active form dihydrotestosterone, reduces excessive prostate growth. Recently Scutellaria baicalensis has been related reports about the effect of baicalein on anti-proliferation of the prostate gland. In this study, we investigated the effects of Scutellaria baicalensis on cytopathological alterations and expression of 5${\alpha}$-reductase in the rat model of benign prostatic hyperplasia induced by castration and testosterone treatment. Methods : Sprague-Dawley rat were treated with testosterone after castration for induction of experimental benign prostatic hyperplasia, which is similar to human benign prostatic hyperplasia in histopathological profiles. Scutellaria baicalensis as an experimental specimen, and finasteride as a positive control, were administered orally. The prostates were evaluated by histopathological changes, testosterone levels, and the expression of 5${\alpha}$-reductase genes. Results : While prostates of control rats revealed severe acinar gland atrophy and stromal proliferation, the rats treated with Scutellaria baicalensis showed a diminished range of tissue damage. In the reverse transcription-polymerase chain reaction(RT-PCR) of 5${\alpha}$-reductase genes. Scutellaria baicalensis inhibited the expression of 5${\alpha}$-reductase genes. Conclusions : These findings suggest that Scutellaria baicalensis may protect glandular epithelial cells and also inhibit stromal proliferation in association with the suppression of 5${\alpha}$-reductase. From theses results, we suggest that Scutellaria baicalensis could be a useful remedy agent for treating benign prostatic hyperplasia.

• Journal of the Korean Wood Science and Technology
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• v.40 no.4
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• pp.294-301
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• 2012

In this study, we investigated the features of bioethanol fermentation of corncob biomass after oxalic acid pretreatment as well as enzymatic hydrolysis. The enzymatic hydrolysis was performed with Accellerase 1000 and the highest yield of monomeric sugars ($64.8g/{\ell}$) was obtained at $50^{\circ}C$ and pH 4.5 for 96 hrs hydrolysis period. For the ethanol fermentation the monomeric sugars obtained from pretreated corncob were subjected to the biological treatment using Pichia stipitis CBS 6054. It was turned out that ethanol production from oxalic acid pretreated corncob was the most feasible at 10~14% of biomass loading as well as 15 FPU enzyme amount. Under these fermentation condition, the ethanol yield was approached to 0.47 after 24 hrs fermentation period, which was corresponded to 92.2% of conversion rate.

• Nutrition Research and Practice
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• v.7 no.3
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• pp.172-177
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• 2013

Benign prostatic hyperplasia (BPH) is one of the most common diseases among elderly men. As the old-age population is increasing recently, it is to our interest to observe the growing BPH within them. In BPH, the dihydrotestosterone (DHT) acts as promotes prostate growth. It inhibits enzyme $5{\alpha}$-reductase that is involved in the conversion of testosterone to the DHT activity which reduces the excessive prostate growth. Through experiments, the effects of Phellius linteus water extract performed on the BPH rats were induced by testosterone treatments. For 12 weeks, Sprague-Dawley rats were treated with testosterone for the induction of BPH. Rats were divided into four experimental groups: the not treated group (N), the testosterone injection and D.W treatment group (TN), the testosterone injection and Phellinus linteus treatment group (TP) and testosterone injection and finasteride treatment group (TF). Prostate weight, volume and weight ratio in the TP group and the TF group were significantly lower than the TN group. Testosterone and DHT levels in the TN group were significantly higher than that of the N group. And the TP group was significantly decreased than that of the TN group. While prostates of control rats revealed severe acinar gland atrophy and stromal proliferation; the TP and TF groups showed trophic symptoms and were lined by flattened epithelial cells, thus, the stromal proliferation is relatively low as compared to the TN group. These suggest that Phellinus linteus water extracts may be an useful remedy for treating the benign prostatic hyperplasia.

• The Journal of Internal Korean Medicine
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• v.31 no.3
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• pp.457-466
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• 2010

Objective : In benign prostatic hyperplasia, dihydrotestosterone acts as a potent cellular androgen and promotes prostate growth. Inhibiting enzyme $5{\alpha}$-reductase that is involved in the conversion of testosterone to the active form dihydrotestosterone reduces this excessive prostate growth. The mechanism on benign prostatic hyperplasia is substantiating evidence to support the clinical value in the evaluation of therapeutic efficacy. In this study, we investigated the effects of Lygodium japonicum on cyto-pathological alterations and expression of $5{\alpha}$-reductase in the rat model of benign prostatic hyperplasia induced by castration and testosterone treatment. Methods : Sprague-Dawley rats were treated with testosterone after castration for induction of experimental benign prostatic hyperplasia, which is similar to human benign prostatic hyperplasia in histopathological profiles. Lygodium japonicum as an experimental specimen, and finasteride as a positive control, were administered orally. The prostates were evaluated by histopathological changes and testosterone levels. Also, the prostates were observed by hematological alterations of AST, ALT, ${\gamma}$-GTP, BUN and creatinine. Results : The rats treated with Lygodium japonicum showed a diminished range of luminal cell and duct epithelial cell damage. The stromal elements and connective tissue proliferation of Lygodium japonicum treated group as compared to the control group decreased. Conclusions : These findings suggest that Lygodium japonicum may protect the glandular epithelial cells. We concluded that Lygodium japonicum could be a useful remedy agent for treating the benign prostatic hyperplasia.

• Proceedings of the Korean Society of Applied Pharmacology
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• 1997.04a
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• pp.90-90
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• 1997

Natural products, which have been used for the treatment of hypertension, diuresis and nephritis in traditional oriental medicine, were selected for the screening of nitric oxide (NO) production in endothelial cells and kidney tissues in vitro as well as in vivo by measuring the conversion of [$\^$14/C]-L-arginine to [$\^$14/C]-L-citrulline, a coproduct of the enzyme reaction with NO. Confluent monolayer of endothelial cells were used for the screening of 16 natural products. Among the natural products, Zizyphus jujuba and Codonopsis pilosula stimulated endothelial NO synthase activity. Thus, both confluent monolayer of endothelial cells and kidney homogenates (glomeruli, cortical tubules, meudllae) were treated with Zizyphus jujuba and Codonopsis pilosula (final concentration 10 $\mu\textrm{g}$/$m\ell$) and NO releases were compared with those by receptor - dependent agonists, bradykinin and ADP and receptor - independent calcium ionophore A23187 in vitro. In rat experiment, NO releases in glomeruli, cortical tubules and medullae and plasma renin activity were assessed after intraperitoneal injection of Zizyphus jujuba and Codonopsis pilosula (10 mg/kg/day for 4 days). As a result, both Zizyphus jujuba and Codonopsis pilosula significantly increased NO releases in cultured endothelial cells, kidney tissues in vitro as well as in vivo. Stimulation of NO releases by Zizyphus jujuba and Codonopsis pilosula was similar to those by receptor - dependent agonists, bradykinin and ADP and receptor - independent calcium ionophore A23187 in cultured endothelial cells. However, plasma renin activity was not influenced by these two natural products. In conclusion, stimulatory effects of Zizyphus jujuba and Codonopsis pilosula on NO release in kidney may contribute their hypotensive effects and antinephritic action possibly by increasing renal blood flow.

• Journal of Microbiology and Biotechnology
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• v.26 no.10
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• pp.1781-1789
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• 2016

Glargine insulin is a long-acting insulin analog that helps blood glucose maintenance in patients with diabetes. We constructed the pPT-GI vector to express prepeptide glargine insulin when transformed into Escherichia coli JM109. The transformed E. coli cells were cultured by fed-batch fermentation. The final dry cell mass was 18 g/l. The prepeptide glargine insulin was 38.52% of the total protein. It was expressed as an inclusion body and then refolded to recover the biological activity. To convert the prepeptide into glargine insulin, citraconylation and trypsin cleavage were performed. Using citraconylation, the yield of enzymatic conversion for glargine insulin increased by 3.2-fold compared with that without citraconylation. After the enzyme reaction, active glargine insulin was purified by two types of chromatography (ion-exchange chromatography and reverse-phase chromatography). We obtained recombinant human glargine insulin at 98.11% purity and verified that it is equal to the standard of human glargine insulin, based on High-performance liquid chromatography analysis and Matrix-assisted laser desorption/ionization Time-of-Flight Mass Spectrometry. We thus established a production process for high-purity recombinant human glargine insulin and a method to block Arg (B31)-insulin formation. This established process for recombinant human glargine insulin may be a model process for the production of other human insulin analogs.

• Journal of Microbiology and Biotechnology
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• v.29 no.12
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• pp.1882-1893
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• 2019

β-Glucosidases and β-xylosidases are two categories of enzymes that could cleave out non-reducing, terminal β-D-glucosyl and β-D-xylosyl residues with release of D-glucose and D-xylose, respectively. In this paper, two functional β-glucosidase Dth3 and β-xylosidase Xln-DT from Dictyoglomus thermophilum were heterologously expressed in E.coli BL21 (DE3). Dth3 and Xln-DT were relatively stable at 75℃ and were tolerant or even stimulated by glucose and xylose. Dth3 was highly tolerant to glucose with a K_i value of approximately 3 M. Meanwhile, it was not affected by xylose in high concentration. The activity of Xln-DT was stimulated 2.13-fold by 1 M glucose and 1.29-fold by 0.3 M xylose, respectively. Furthermore, the βglucosidase Dth3 and β-xylosidase Xln-DT showed excellent selectivity to cleave the outer C-6 and C-3 sugar moieties of ASI, which established an effective and green method to produce the more pharmacologically active CAG, an exclusive telomerase activator. We measured temperature, pH and dosage of enzyme using a single-factor experiment in ASI biotransformation. After optimization, the optimal reaction conditions were as follows: 75℃, pH 5.5, 1 U of Dth3 and 0.2 U of Xln-DT, respectively. Under the optimized conditions, 1 g/l ASI was transformed into 0.63 g/l CAG with a corresponding molar conversion of 94.5% within 3 h. This is the first report to use the purified thermostable and sugar-tolerant enzymes from Dictyoglomus thermophilum to hydrolyze ASI synergistically, which provides a specific, environment-friendly and cost-effective way to produce CAG.

• Journal of Energy Engineering
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• v.24 no.3
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• pp.1-5
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• 2015

This study is to investigate the effect of torrefaction on enzymatic hydrolysis of lignocellulosic biomass for bio-ethanol production. As a pretreatment, the torrefaction of lignocellulosic biomass was conducted in temperature of $250{\sim}350^{\circ}C$ in the absence of oxygen. Tween-80, nonionic surfactant, was tested to enhance saccharification efficiency by coping with hydrophobicity resulted from torrefaction. As a result, the glucose production from enzymatic hydrolysis of biomass pretreated by torrefaction was greater than that obtained from the non-pretreated biomass. Sugar conversion was higher when the biomass was saccharified with addition of tween-80. It was found that torrefaction can be applied as a preptreatment for lignocellulosic biomass and tween-80 is needed to enhance its enzyme saccharification.

• Clinical and Experimental Pediatrics
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• v.48 no.6
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• pp.665-668
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• 2005

"Rickets" is the term applied to impaired mineralization at epiphyseal growth plate, resulting in deformity and impaired linear growth of long bones. Rickets may arise as a result of vitamin D deficiency or abnormality in metabolism. Vitamin D-dependent rickets(VDDR) is rare autosomal recessive disorder in which affected individuals have clinical features of vitamin D deficiency. In 1961, Prader first described this disorder including severe clinical features of rickets, such as hypophosphatemia, hypocalcemia, muscle weakness and seizure. Two distinctive hereditary defects, type I VDDR and type II VDDR have been recognized in vitamin D metabolism. Type I VDDR may be due to congenital defects of renal 1 ${\alpha}$-hydroxylase, the enzyme responsible for conversion of $25(OH)D_3$. These patients have low to detectable $1,25(OH)_2D_3$ in presence of normal to raised $25(OH)D_3$. In type II VDDR, renal production of $1,25(OH)_2D_3$ is intact but $1,25(OH)_2D_3$ is not used effectively and target organ resistant to $1,25(OH)_2D_3$ is respectively derived from the abnormality in the vitamin D receptor. We report a case of a 25 month-old girl with typical clinical features of VDDR type I rickets, hypocalcemia, increased alkaline phosphatase and secondary hyperparathyroidism.