• Korean Chemical Engineering Research
• /
• v.54 no.5
• /
• pp.665-670
• /
• 2016

This study deals with the possible degradation of toluene and acetic acid when subjected to cell-free enzyme system from the toluene degrading bacteria Pseudomonas putida and acetic acid degrading bacteria Cupriavidus necator. P. putida produces toluene dioxygenase only under the existence of toluene in culture medium and toluene is degraded to cis-toluene dihydrodiol by this enzyme. C. necator produces acetyl coenzyme A synthetase-1 and converts acetic acid to acetyl CoA in order to synthesize ATP to need for growth or PHA which is biodegradable polymer. In case of toluene degradation, the experiment was conducted before and after production of toluene dioxygenase as this enzyme, produced by P. putida, is an inducible enzyme. Toluene was detected using gas chromatography (GC). Similar amount of toluene was found in control group and before production of toluene dioxygenase (experimental group 1). However, reduction in toluene was detected after the production of toluene dioxygenase (experimental group 2). Acetic acid was detected through application of gas chromatography-mass spectrometer (GC-MS). The results showed the acetic acid peak was not detected in the experimental group to apply cell-free enzyme system. These results show that the cell-free enzyme system obtained from P. putida and C. necator retained the ability to degrade toluene and acetic acid. However, P. putida needs to produce the inducible enzyme before preparation of the cell-free enzyme system.

• Mass Spectrometry Letters
• /
• v.11 no.4
• /
• pp.108-112
• /
• 2020

A certified reference material (CRM) for the analysis of nutrient elements in an edible mushroom (Ganoderma lyceum) powder has been developed (KRISS CRM 108-10-011). The mass fractions of calcium (Ca), iron (Fe), and zinc (Zn) were measured by isotope dilution inductively coupled plasma mass spectrometry (ID ICP/MS). To dissolve the fungi cell wall of mushroom consisted of chitin fibers, sample preparation method by single reaction chamber type microwave-assisted acid digestion with acid mixtures was optimized. The mean measurement results obtained from 12 sample bottles were used to assign as the certified values for the CRM and the between-bottle homogeneities were evaluated from the relative standard deviations. The certified values were metrologically traceable to the definition of the kilogram in the International System of Units (SI). This CRM is expected to be used for validation of analytical methods or quality control of measurement results in analytical laboratories when they determine the mass fractions of elements in mushroom or other similar samples.

• Asian-Australasian Journal of Animal Sciences
• /
• v.20 no.2
• /
• pp.208-213
• /
• 2007

The objective of the experiment was to determine the optimum cultural [moisture levels (55, 60 and 70%), days of fermentation (7, 14 and 21), temperature (25 and $35^{\circ}C$) of incubation)] and nutritional parameters (urea addition (0 and 2%) and variable levels of single super phosphate (0.25 and 0.50% SSP)) for bio-processing of the mustard (Brassica campestris) straw (MS) under solid-state fermentation (SSF) system. The performance of SSF was assessed in terms of favorable changes in cell wall constituents, protein content and in vitro DM digestibility of the MS. Sorghum based inoculum (seed culture) of Ganoderma lucidum to treat the MS was prepared. The 50 g DM of MS taken in autoclavable polypropylene bags was mixed with a pre-calculated amount of water and the particular nutrient in the straw to attained the desired levels of water and nutrient concentration in the substrate. A significant progressive increase in biodegradation of DM (p<0.001), NDF (p<0.01) and ADF (p<0.05) was observed with increasing levels of moisture. Among the cell wall constituents the loss of ADF fraction was greatest compared to that of NDF. The loss of DM increased progressively as the fermentation proceeded and maximum DM losses occurred at 28 days after incubation. The protein content of the treated MS samples increased linearly up to the day $21^{th}$ of the incubation and thereafter declined at day $28^{th}$, whereas the improvement in in vitro DM digestibility were apparent only up to the day $14^{th}$ of the incubation under SSF and there after it declined. The acid detergent lignin (ADL) degradation was slower during the first 7 days of SSF and thereafter increased progressively and maximum ADL losses were observed at the day $28^{th}$ of the SSF. The biodegradation of DM and ADL was not affected by the variation in incubation temperature. Addition of urea was found to have inhibitory effect on fungal growth. The effect of both the levels (0.25 and 0.50) of SSP addition in the substrate, on DM, NDF, ADF, cellulose and ADL biodegradation was similar. Similarly, the protein content and the in vitro DM digestibility remain unaffected affected due to variable levels of the SSP inclusion in the substrate. From the results it may be concluded that the incubation of MS with 60 percent moisture for 21 days at $35^{\circ}C$ with 0.25 percent SSP was most suitable for MS treatment with Ganoderma lucidum. Maximum delignification, enrichment in the protein content and improvement in in vitro DM digestibility were achieved by adopting this protocol of bioprocessing of MS.

• Journal of Sensor Science and Technology
• /
• v.7 no.2
• /
• pp.131-139
• /
• 1998

$CdS_{0.67}Se_{0.33}$ single crystal was grown by vertical sublimation method of closed tube physical vapour deposition. The (0001) growth plane of oriented single crystals was confirmed from the back-ref1ection Laue patterns. From the Hall effects by van der Pauw method, the as-grown $CdS_{0.67}Se_{0.33}$ single crystals were found to be n-type semiconductors. The mobility appeared to be decreased by lattice scattering at temperature range from 150K to 293K and by impurity scattering at temperatures ranging from 30K to 150K In order to explore its applicability in photoconductive cells, we measured the ratio of photo-current to dark-current (pc/dc), maximum allowable power dissipation (MAPD), spectral response and response time respectively. The results indicated that for the samples annealed in Cu vapour the photoconductive characteristics are best. We obtained sensitivity of 0.99, the value of pc/de of $1.84{\times}10^{7}$, the MAPD of 323mW and the rise and decay time of 9.3 ms and 9.7 ms, respectively.

• Molecules and Cells
• /
• v.37 no.12
• /
• pp.888-898
• /
• 2014

Pancreatic cancer is one of the most fatal cancers and is associated with limited diagnostic and therapeutic modalities. Currently, gemcitabine is the only effective drug and represents the preferred first-line treatment for chemotherapy. However, a high level of intrinsic or acquired resistance of pancreatic cancer to gemcitabine can contribute to the failure of gemcitabine treatment. To investigate the underlying molecular mechanisms for gemcitabine resistance in pancreatic cancer, we performed label-free quantification of protein expression in intrinsic gemcitabine-resistant and -sensitive human pancreatic adenocarcinoma cell lines using our improved proteomic strategy, combined with filter-aided sample preparation, single-shot liquid chromatography-mass spectrometry, enhanced spectral counting, and a statistical method based on a power law global error model. We identified 1931 proteins and quantified 787 differentially expressed proteins in the BxPC3, PANC-1, and HPDE cell lines. Bioinformatics analysis identified 15 epithelial to mesenchymal transition (EMT) markers and 13 EMT-related proteins that were closely associated with drug resistance were differentially expressed. Interestingly, 8 of these proteins were involved in glutathione and cysteine/methionine metabolism. These results suggest that proteins related to the EMT and glutathione metabolism play important roles in the development of intrinsic gemcitabine resistance by pancreatic cancer cell lines.

• Journal of Plant Biotechnology
• /
• v.34 no.2
• /
• pp.139-144
• /
• 2007

Hypocotyl explants of Chinese cabbage (cvs. "Jeong Sang") produced transgenic calli on callus induction medium (MS salt, B5 vitamin, 5 mg/L acetosyringone, 1 mg/L 2,4-D, 3% sucrose, 400 mg/L cefotaxime, 100 mg/L paromomycin, pH 5.8) after cocultivation with strains of Agrobacterium tumefaciens (EHA101, LBA4404, GV3101) harboring the pPTN290 containing paromomycin-resistance gene as a selectable marker, and then they transferred to root induction medium (1/2MS salt, MS vitamins, 2% sucrose, 100 mg/L paromomycin, 100 mg/L cefotaxime, pH 5.8) and shoot induction medium (MS salt, B5 vitamin, 4 mg/L $AgNO_3$, 4 mg/L 6-benzyladenine, 3 mg/L alpha-naphthaleneacetic acid, 100 mg/L paromomycin, 100 mg/L cefotaxime, 3% sucrose, pH 5.8) in order. There was a significant difference in the frequency of transgenic calli depending on Agrobacterium strains. In particular, the highest frequency (6.1%) of transgenic calli was obtained from the hypocotyls cocultivated with EHA101 strains. Also, the frequency (%) of transgenic root and plants from each transgenic callus clone were obtained with 60.7% and 38.2% in EHA101, with 8.3% and 0% in LBA4404, with 20.5% and 85.7% in GV3101 strains, respectively. They were grown to maturity in a greenhouse and normally produced $T_2$ seeds. GUS histochemical assay for progeny ($T_2$) revealed that the transgenes was expressed in the plant genome, and progeny analysis from 7 independent transgenic events demonstrated that the transformants transmitted the transgene as a single or multiple functional locus.

• The Korean Journal of Physiology
• /
• v.25 no.2
• /
• pp.125-131
• /
• 1991

Inactivation properties of Ca current in the unfertilized eggs of mouse were studied by using the whole cell voltage clamp technique and single microelectrode voltage clamp technique. Membrane potential was held at -80 mV and step depolarization was applied from -50 mV to 50 mV for $200{\sim}500\;ms$. Peak of inward Ca currents was $-2{\sim}-4\;nA$ at a membrane Potentials from -20 mV to 0 mV and outward currents were not observed within the membrane voltage range studied $(-50{\sim}50\;mV)$. Inward currents were fully inactivated within 200 ms after the onset of step depolarization. As the membrane became depolarized, time constant of inactivation (${\tau}$) was decreased but remained around $20{\sim}30\;ms$ beyond 10 mV. When $Ca^{2+}$ was used as a charge earlier, inactivation of inward $Ca^{2+}$ current also occured and time course of inactivation was similar to that of $Ca^{2+}$ currents as charge carrier. In the bathing solution containing high potassium $(131\;mM\;K^+)$, process of inactivation was not changed except a parallel decrease of value for the entire range of membrane potential. Steady-state inactivation of the $current(h_{\infty})$ obtained from the double pulse experiment showed the voltage-dependent change. These results suggested that inactivation of Ca currents in the unfertilized eggs of mouse was voltage-dependent.

• Journal of Plant Biology
• /
• v.37 no.3
• /
• pp.365-370
• /
• 1994

Excised cotyledon segments of ginseng zygotic embryos at various developmental stages were cultured on MS basal medium from which somatic embryos were directly induced. The frequency of somatic embryo formation on the segments declined with the advancing zygotic embryo maturity. All of the cells in the cotyledons of immature zygotic embryos were smaller and more densely cytoplasmic than those in mature embryos. Histological examinations revealed that the poly-somatic embryos formed on immature embryos were of multi-cell originand derived from the epidermal and subepidermal cell layers. However, in the cotyledon of germinating zygotic embryos, only theepidermal cells were densely cytoplasmic and singularly competent to develop into somatic embryos resulting into single embryos at a frequency of 100%.

• Asian Pacific Journal of Cancer Prevention
• /
• v.16 no.9
• /
• pp.3691-3696
• /
• 2015

Background: Cancer loci comprise heterogeneous cell populations with diverse cellular secretions. Therefore, disseminating cancer-specific or cancer-associated protein antigens from tissue lysates could only be marginally correct, if otherwise not validated against precise standards. Materials and Methods: In this study, 2DE proteomic profiles were examined from lysates of 13 lung-adenocarcinoma tissue samples and matched against the A549 cell line proteome. A549 matched-cancer-specific hits were analyzed and characterized by MALDI-TOF/MS. Results: Comparative analysis identified a total of 13 protein spots with differential expression. These proteins were found to be involved in critical cellular functions regulating pyrimidine metabolism, pentose phosphate pathway and integrin signaling. Gene ontology based analysis classified majority of protein hits responsible for metabolic processes. Among these, only a single non-predictive protein spot was found to be a cancer cell specific hit, identified as Armadillo repeat-containing protein 8 (ARMC8). Pathway reconstruction studies showed that ARMC8 lies at the centre of cancer metabolic pathways. Conclusions: The findings in this report are suggestive of a regulatory role of ARMC8 in control of proliferation and differentiation in lung adenocarcinomas.

• The Journal of Korean Institute of Communications and Information Sciences
• /
• v.32 no.7A
• /
• pp.710-716
• /
• 2007

In this paper, a new scheme of downlink co-channel interference (CCI) cancellation in OFDM cellular networks is introduced for users at the cell-edge. Coordinated symbol transmission between base stations (BS) is operated where the same symbol is transmitted from different BS on different sub-carriers. At the mobile station (MS) receiver, we introduce a soft decision maximum likelihood CCI canceler and a modified maximum ratio combining (M-MRC) to obtain an estimate of the transmitted symbols. Weights used in the combining method are derived from the channels coefficients between the cooperated BSs and the MS. Simulations show that the proposed scheme works well under frequency-selective channels and frequency non-selective channels. A gain of 9 dB and 6 dB in SIR is obtained under multipath fading and flat-fading channels, respectively.