• Journal of Microbiology and Biotechnology
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• v.11 no.1
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• pp.21-28
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• 2001

Enzyme linked-immunosorbent assay (ELISA) for a rapid detection of fungi, Aspergillus and Penicillium genera in food, were developed and their efficiencies were approved by detecting artificially contaminated agricultural commodities. Mice were immunized with partially purified Aspergillus flavus extracellualr polysaccharide (EPS) and lymph node cells of the mice were fused with the myeloma cells for production of monoclonal antibodies. Mab 1G11, one of the antibodies, was selected and purified. A sandwich ELISA was established and its detection limit toward A. flavus EPS was 1mg/ml. Among the 59 strains tested (including 18 species of Aspergillus, 16 of Penicillium, 11 of Fusarium, 1 of Absidia, 2 of Alternaria, 2 of Candida, 2 of Cladosporium, 2 of Geotrichum, 2 of Mucor, 2 of Rhizopus, 1 of Trichoderma), species of Aspergillus and penicillium had a high reactivity with Mab 1G11 even up to 10,000 times dilution of culture broths. The other genera except Cladosporium resinae showed no reactivity, thus Mab 1G11 was specific to the genera of Aspergillus and Penicillium. The epitope of A. flavus EPS against monoclonal Mab 1G11 was on the carbohydrate moiety when 1 to 100$\mu g/g$ A. flavus EPS were put into rice, potato, and mandarin orange, the average recoveries detected by sandwich ELIA were 123, 59, and 76%, respectively. Correlation was found to be linear between the EPS, and mycelium of A. flavus and Penicillium citrinum grown in a liquid medium (r=0.87 and 0.96), and also between the EPS and colony forming unit in solid media of rice of potato (r=0.91-0.99).

• KSBB Journal
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• v.31 no.4
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• pp.284-290
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• 2016

In this research, recombinant human cytotoxic T-lymphocyte antigen 4-immunoglobulin (hCTLA4Ig) was produced by transgenic rice cells. RAmy3D promoter was used for overcome the limitation of low expression level in transgenic plant cells, and the secretion of target protein was accomplished by signal peptide. However, the RAmy3D promoter system which can be induced only by sugar starvation causes the decrease of cell viability. As a result, cell death promotes the release of protease which degrades the target proteins. The protein stability and productivity can be significantly influenced by proteolysis activity. Therefore, development of new strategies are necessary for the in situ recovery of target proteins from cell culture media. In this study, in situ recovery was performed by various strategies. Direct addition of Protein A resin with nylon bag leads to cell death by increased shear stress and decrease in production of hCTLA4Ig by protease. Medium exchange through modified flask could recover hCTLA4Ig with high cell viability and low protease activity, on the other hand, the productivity was lower than that of control. When in situ recovery was conducted at day 7 after induction in air-lift bioreactor, 1.94-fold of hCTLA4Ig could be recovered compared to control culture without in situ recovery. Consequently, in situ recovery of hCTLA4Ig from transgenic rice cell culture could enhance productivity significantly and prevent degradation of target proteins effectively.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.42 no.5
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• pp.615-625
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• 1997

An efficient protocol for plant regeneration from protoplasts of the indica rice variety IR43 has been developed. The procedure involved plating of embryogenic suspension-derived protoplasts on the surface of a filter membrane overlaying agarose-embedded feeder cells. Lolium multiflorum cell suspensions were preferable to these of Oryza ridleyi as feeder cells and Lolium suspensions supported colony formation from up to 0.68％ of the protoplasts, depending on the age of cell suspensions. Plant regeneration frequency was significantly improved by using maltose alone or in a 1:1(w/w) combination with sucrose as carbohydrate source and a simple dehydration treatment using a high concentration of agarose in the regeneration medium. Medium containing maltose or maltose mixed with sucrose increased the plant regeneration frequency compared with medium containing sucrose alone. The plant regeneration frequency was increased to 30.7 to 70.7％ following dehydration treatment, while the non-treated controls showed a regeneration frequency of 3.1 to 30.6％. Protoplast-derived plants were transferred to the glasshouse, flowered with morphologically normal.

• Journal of Applied Biological Chemistry
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• v.54 no.1
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• pp.21-25
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• 2011

A lactic acid bacterial strain showing high acid production in saccharified-rice suspension was isolated from Kimchi. This strain was analyzed by API 50 CHL kit and 16S rRNA sequencing analysis and identified as Leuconostoc mesenteroides 310-12. Saccharified-rice suspension was fermented using L. mesenteroides 310-12 strain at $30^{\circ}C$ for 15 h. The changes of pH, titratable acidity and viable cell number during fermentation were determined. The pH and titratable acidity were reached to pH 3.57 and 0.40% after 15 h fermentation, respectively. The viable cell population of L. mesenteroides 310-12 was rapidly increased to $8.9{\times}10^8$ CFU/g during the 15 h of cultivation. The contents of lactic acid and acetic acid were determined to be 0.077% and 0.065% after 15 h fermentation, respectively. The rice-based fermented beverage was manufactured by blending L. mesenteroides 310-12 fermented broth and some food additives. When this beverage was stored at $4^{\circ}C$, the viable cells population was decreased to $1.0{\times}10^7$ CFU/g and pH was nearly maintained for 25 days.

• Food Science of Animal Resources
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• v.27 no.3
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• pp.371-376
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• 2007

This study was conducted to evaluate the inhibitory effects of Phellinus linteus mushroom rice on food-borne pathogens (Staphylococcus aureus 305, Listeria monocytogenes ATCC 19114, Escherichia coli 0157:H7 ATCC 42894, Escherichia coli O55) and human rotavirus (KU, S2, YO, K-21). The results obtained are summarized as follows: The inhibitory effects of Phellinus linteus mushroom rice against food-borne pathogens; inhibition zone diameters for S. aureus 305, L. monocytogenes ATCC 19114 and E. coli 0157:H7 ATCC 42894 were 18mm, 20mm and 13mm, respectively. E. coli O55 did not form an inhibition zone. The inhibitory effects of l/3% Phellinus linteus mushroom rice on MA-104 cells using the MTT assay were, KU $90.52{\pm}18.42%,\;S2\;94.74{\pm}8.68%,\;YO\;59.77{\pm}8.68%$ and $K-21\;97.56{\pm}12.50%$. Phellinus linteus mushroom rice has inhibitory effects on the food-borne pathogens S. aureus 305, L. monocytogenes ATCC 19114 and E. coli 0157:H7 ATCC 42894, and human rotavirus (K-21, S2, YO, KU).

• Molecules and Cells
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• v.20 no.3
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• pp.385-391
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• 2005

As a first step towards identifying genes involving in the signal transduction pathways mediating rice blast resistance, we isolated 3 mutants lines that showed enhanced susceptibility to rice blast KJ105 (91-033) from a T-DNA insertion library of the japonica rice cultivar, Hwayeong. Since none of the susceptible phenotypes co-segregated with the T-DNA insertion we adapted a map-based cloning strategy to isolate the gene(s) responsible for the enhanced susceptibility of the Hwayeong mutants. A genetic mapping population was produced by crossing the resistant wild type Hwayeong with the susceptible cultivar, Nagdong. Chi-square analysis of the $F_2$ segregating population indicated that resistance in Hwayeong was controlled by a single major gene that we tentatively named Pi-hy. Randomly selected susceptible plants in the $F_2$ population were used to build an initial map of Pi-hy. The SSLP marker RM2265 on chromosome 2 was closely linked to resistance. High resolution mapping using 105 $F_2$ plants revealed that the resistance gene was tightly linked, or identical, to Pib, a resistance gene with a nucleotide binding sequence and leucine-rich repeats (NB-LRR) previously isolated. Sequence analysis of the Pib locus amplified from three susceptible mutants revealed lesions within this gene, demonstrating that the Pi-hy gene is Pib. The Pib mutations in 1D-22-10-13, 1D-54-16-8, and 1C-143-16-1 were, respectively, a missense mutation in the conserved NB domain 3, a nonsense mutation in the 5th LRR, and a nonsense mutation in the C terminus following the LRRs that causes a small deletion of the C terminus. These findings provide evidence that NB domain 3 and the C terminus are required for full activity of the plant R gene. They also suggest that alterations of the resistance gene can cause major differences in pathogen specificity by affecting interactions with an avirulence factor.

• Journal of the Korean Society of Food Science and Nutrition
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• v.46 no.5
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• pp.562-571
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• 2017

In this study, we investigated the anti-oxidant activities [electron-donating ability (EDA), 2,2'-azino-bis (3-ethylbenzothiazoline-6-sulfonic acid) (ABTS) radical scavenging ability, and reactive oxygen species (ROS) inhibitory activity], anti-wrinkle activities [collagenase inhibitory activity, suppression and/or phosphorylation of matrix metalloproteinases (MMPs), and mitogen-activated protein (MAP) kinase activity], and mRNA expression levels using reverse transcription-polymerase chain reaction (RT-PCR) assay in ultraviolet (UV) B ray ($50mJ/cm^2$)-irradiated human keratinocyte HaCaT cells. Josaengheugchal, Sinneungheugchal (SE), Shintoheug rice, Heugjinju rice, and Heugseol (HE) among colored rice varieties were reported to have excellent antioxidant properties. In the EDA and ABTS radical scavenging assays, extracts of the five colored rice varieties had scavenging activities of 72% at concentrations higher $50{\mu}g/mL$. In the collagenase inhibition assay, ethanol extracts of the five colored rice varieties showed high inhibitory effects of about 60% at concentrations higher $25{\mu}g/mL$. In the ROS inhibition assay, ethanol extracts of HE and SE showed very excellent inhibition efficacies at all concentrations. We determined molecular biological mechanisms of MMPs (MMP-1, -3, -8, and -13) and mitogen-activated protein kinase (MAPK) with HE, and the results show that HE suppressed expression of MMPs and phosphorylation of MAPK and increased expression of pro-collagen type I in UVB-irradiated cells. It was also confirmed by RT-PCR that HE reduced expression of MMPs mRNA. Therefore, these results suggest that HE has anti-wrinkle and collagen production effects and may be used as a material in the development of functional food and cosmetic industries.

• Korean Journal of Plant Tissue Culture
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• v.24 no.5
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• pp.295-303
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• 1997

To investigate the response on feeder cell cultures, protoplasts isolated from cell suspensions initiated from mature seed scutellum-derived callus of the Japonica rice variety Taipei 309, were cultured on filter membranes under various conditions. The effects of various factors, such as gelling agents, feeder cell and protoplast densities, species of feeder cells and heat shock treatment, have been investigated to improve protoplast plating efficiencies on filter membranes. Maximum protoplast plating efficiencies were obtained when protoplasts were cultured on KPR medium semi-solidified with Sea Plaque agarose at a density of $5\;\times\;10^{5}\;ml^{-1}$ protoplasts in the presence of Lolium multiflorum as feeder cells (0.5 ml pcv per 10 ml of protoplast culture medium). Pre-culture heat shock treatments for 1 min. and 5 min. to the protoplasts did not give any appreciable increase on the plating efficiency of protoplasts in the presence of feeder cells. Maltose-supplemented medium was superior for plant regeneration from protoplast-derived colonies compared with medium containing only sucrose. The plants were transferred to the glasshouse, flowered and were fertile.

• Korean Journal of Plant Tissue Culture
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• v.25 no.2
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• pp.81-88
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• 1998

The Southeast Asian javanica rice variety Tinawen was investigated for efficient protoplast culture and plant regeneration from cell suspension-derived protoplasts using a feeder cell culture method. Feeder cells of both Lolium multiflorum and Oryza ridleyi, either alone, or in combination, were employed and plants were regenerated from protoplast-derived colonies on several plant regeneration media. Dehydration of protoplast-derived colonies was also investigated as a means of enhancing plant regeneration. In the presence of L. multiflorum or O. ridleyi feeder cells, the protoplast plating efficiency ranged from 0.09% to 1.48%, depending on the feeder cell type and the age of the cell suspension. L. multiflorum feeder cells induced approximately 6-fold higher plating efficiency compared with those of O. ridleyi. The plant regeneration frequencies were 19.3-31.7% with L. multiflorum, 13.0-18.0% with O. ridleyi and 18.0-22.0% with a mixture of both in various plant regeneration media when protoplast-derived colonies were dehydrated, while for the non-dehydrated colonies, the values were 2.0-7.0%, 3.0-5.0% and 0-4.0%, respectively. Flow cytometric analysis of 34 protoplast-derived plants showed that the majority of plants were diploids and only 2 plants were tetraploids. The plants which were transferred to glasshouse were fertile.

• Journal of Life Science
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• v.31 no.2
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• pp.192-198
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• 2021

Red yeast rice has been extensively used as food and traditional medicine for thousands of years in East Asian countries. It is produced by the fermentation of a particular yeast (in general, Monascus purpureus) as rice and various cereals (barley, soybean, etc.). Monascus sp. produces many secondary metabolites during its growth, including pigments, monacolins, and γ-aminobutyric acid. Some metabolites―specifically, monacolin K, γ-aminobutyric acid, dimerumic acid, and monascus pigments―have been reported to lower cholesterol and blood pressure while showing anti-obesity effects. In this study, we investigated the anti-obesity effect of ethanol extract from red yeast barley (RYB) fermented with Monascus sp. BHN-MK 2 on 3T3-L1 cells. The anti-obesity effects of RYB extract were examined: its lipid accumulation inhibitory effect was tested by Oil Red O staining, and obesity-related mRNA expression levels were tested by real-time RT-PCR in MDI stimulated 3T3-L1 cells. The intracellular lipid content of MDI-stimulated 3T3-L1 cells decreased significantly to 5.04%, 12.24%, and 23.52% in response to 200, 400, and 800 ㎍/ml RYB, respectively. Moreovers, we evaluated that RYB extract significantly downregulated the expression of C/EBPα, SREBP-1, and PPAR-γ gene in a dose-dependent manner. As a result, red yeast barley ethanol extracts exerted the strongest anti-obesity effects. Also, the results indicate that red yeast barley could be used as a functional anti-obesity food material.