• Korean Journal of Fisheries and Aquatic Sciences
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• v.51 no.6
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• pp.613-622
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• 2018

This study investigated changes in the quality and antioxidant activity of soy sauce with added Saccharina japonica powder (FSP). Soy sauce was prepared with acid-hydrolyzed soy sauce, brewed soy sauce, honey, ginger, garlic, dried red pepper, ${\gamma}$-aminobutyric acid (GABA)-enriched sea tangle fermented in lactic acid, and 1% or 3% S. japonica powder by soy sauce volume. The color, pH, microbiology, amino nitrogen, free amino acids, antioxidant activity, and sensory qualities of the soy sauce were evaluated. There were no significant differences in the general characteristics or antioxidant activity. However, the addition of FSP to the soy sauce enhanced the delicate flavor. Furthermore, soy sauce containing FSP had higher levels of GABA (50 mg/100 mL), a biofunctional ingredient. Therefore, the development of seasoning soy sauce with enhanced functionality seems possible.

• Mycobiology
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• v.50 no.1
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• pp.96-98
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• 2022

The Aspergilli of the section Nidulantes series Versicolores are among the most recurrent molds in indoor environments. These species cause damage to the quality of air. Indeed, they are responsible for allergies, aggravation of asthma and can even cause infections in immunocompromised patients. Molds belonging to the Versicolores series also produce sterigmatocystin, a mycotoxin classified as potential human carcinogen by the International Agency for Research on Cancer (group 2B). Here, we provide for the first time the genome of three species of the series Versicolores: Aspergillus creber, Aspergillus jensenii and Aspergillus protuberus which are the most abundant species of this series in bioaerosols. The genomes of these three species could be assembled with a percentage of completeness of 97.02%, 96.21% and 95.35% for Aspergillus creber, A. jensenii and A. protuberus respectively. These data will allow to study the genes and gene clusters responsible for the expression of virulence factors, the biosynthesis of mycotoxins and the proliferation of these ubiquitous and recurrent molds.

• The Plant Pathology Journal
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• v.39 no.1
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• pp.141-148
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• 2023

Black shoot blight disease caused by Erwinia pyrifoliae has serious impacts on quality and yield in pear production in Korea; therefore, rapid and accurate methods for its detection are needed. However, traditional detection methods require a great deal of time and fail to achieve absolute quantification. In the present study, we developed a droplet digital polymerase chain reaction (ddPCR) method for the detection and absolute quantification of E. pyrifoliae using a pair of species-specific primers. The detection range was 10³-10⁷ copies/ml (DNA templates) and cfu/ml (cell culture templates). This new method exhibited good linearity and repeatability and was validated by absolute quantification of E. pyrifoliae DNA copies from samples of artificially inoculated immature pear fruits. Here, we present the first study of ddPCR assay for the detection and quantification of E. pyrifoliae. This method has potential applications in epidemiology and for the early prediction of black shoot blight outbreaks.

• Korean Journal of Microbiology
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• v.54 no.2
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• pp.98-104
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• 2018

Naegleria fowleri and Acanthamoeba spp. are free-living amoebas that are widely distributed in natural environments. Although uncommon, infection with these protozoans can cause fatal disease in humans and animals. In this study, in order to select the appropriate method to survey Naegleria fowleri and Acanthamoeba spp. in water samples, four molecular biology techniques and one commercially available kit for real-time PCR were compared. The results indicated that the duplex real-time PCR was the most sensitive, and could be used to simultaneously detect two different free-living amoebas. Using the duplex real-time PCR approach, the two free-living amoebas were surveyed in three local streams in Daejeon, Republic of Korea. The concentrated free-living amoebas were inoculated onto non-nutrient agar plates which had been spread with heat-inactivated Escherichia coli and incubated for 5~7 days. After incubation, gDNA was extracted and used as the template for amplification by duplex real-time PCR. Acanthamoeba spp. and N. fowleri was detected from ten (83.3%) and two (16.6%) of the twelve samples, respectively. As these two free-living amoebas can be fatal, continuous surveillance is needed to track their distribution in the aquatic environment for the drinking water safety.

• Korean Journal of Microbiology
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• v.54 no.3
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• pp.237-243
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• 2018

The pathogenic free-living amoebas (FLAs), Acanthamoeba spp. and Naegleria fowleri, can cause fatal infections, including amoebic encephalitis. They are ubiquitously distributed in nature, including in diverse bodies of water. In order to survey Acanthamoeba spp. and N. fowleri in source water in Korea, we used culture-based real-time PCR to detect viable FLAs in 52 source water samples collected between July 2017 and December 2017. Acanthamoeba spp. and N. fowleri were detected in 42 samples (80.8%) and 6 samples (11.5%), respectively. Acanthamoeba spp. were detected at approximately the same frequency in all seasons, but N. fowleri was mainly detected in summer and autumn, with no N. fowleri detected in winter. These results demonstrate that these pathogenic FLAs, especially N. fowleri, which has caused deaths in the United States and China, are widely distributed in the Korean aquatic environment.

• Food Science and Biotechnology
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• v.17 no.5
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• pp.959-964
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• 2008

This study evaluated the effects of dietary fiber extracted from rice bran (rice bran fiber) on the quality of low-fat tteokgalbi. The controls were formulated with 20% added fat. Test samples of tteokgalbi were produced with 5 different formulations containing 1, 2, 3, 4, and 5% rice bran fiber as a fat replacer, in addition to 10% fat. The control had the highest fat content, energy value, cooking loss, reduction in diameter, reduction in thickness, CIE $L^*$-value (lighness), and color of sensory properties. The tteokgalbi containing rice bran fiber had higher moisture, protein, ash, and carbohydrate contents than the controls. Tteokgalbi with 3% rice bran fiber had the lowest cooking loss, reduction in diameter, and reduction in thickness. Meat products containing 2 and 3% rice bran fiber had a higher overall acceptability similar to the high fat control.

• Journal of Korean Society of Environmental Engineers
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• v.28 no.4
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• pp.389-396
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• 2006

A quantitative survey of the protozoa microfauna at two advanced wastewater treatment plants has been carried out on a weekly basis. The abundance of the protozoa were compared with operating parameters and effluent quality using statistical procedures. The protozoa distribution indicated it seemed the composition of the influent wastewater and operating conditions of plant influenced the structure of protozoa in the plant. In statistical analysis, the distribution of protozoa showed the present operating condition of plant and predicted near-future effluent qualify. Enough data concerning protozoa, operating parameters and effluent has been gathered, the operator has a valuable tool for predicting plant performance and near-future data of effluent based on microscopic examination. Perhaps more importantly it can be used to actually control the plant to adjust the operating conditions to obtain the protozoal populations that have been shown to provide the best effluent quality.

• Journal of Environmental Science International
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• v.22 no.9
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• pp.1153-1160
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• 2013

While a range of natural organic matter (NOM) types can generate high levels of disinfection by-products (DBPs) after chlorination, there is little understanding of which specific compounds act as precursors. Use of eight model compounds allows linking of explicit properties to treatability and DBP formation potential (DBPFP). The removal of model compounds by various treatment processes and their haloacetic acid formation potential (HAAFP) before and after treatment were recorded. The model compounds comprised a range of hydrophobic (HPO) and hydrophilic (HPI) neutral and anionic compounds. On the treatment processes, an ozone oxidation process was moderate for control of model compounds, while the HPO-neutral compound was most treatable with activated carbon process. Biodegradation was successful in removing amino acids, while coagulation and ion exchange process had little effect on neutral molecules. Although compared with the HPO compounds the HPI compounds had low HAAFP the ozone oxidation and biodegradation were capable of increasing their HAAFP. In situations where neutral or HPI molecules have high DBPFP additional treatments may be required to remove recalcitrant NOM and control DBPs.

• Animal Bioscience
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• v.34 no.12
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• pp.2003-2011
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• 2021

Objective: The aim of this study was to evaluate the effect of marinating turkey meat with buttermilk and acid whey on the technological traits and microbiological quality of the product. Methods: Slices of turkey meat muscles were marinated for 12 hours in buttermilk (n = 30), acid whey (n = 30) and comparatively, in lemon juice (n = 30). The control group (n = 30) consisted of unmarinated slices of turkey breast muscles. Physical parameters (pH, water holding capacity, colour L^*a^*b^*, shear force, weight loss) were assessed and quantitative and qualitative microbiological evaluation of raw and roasted products was performed. The microbiological parameters were determined as the total viable counts of mesophilic aerobic bacteria, of the Enterobacteriaceae family, and Pseudomonas spp. Bacterial identification was performed by matrix-assisted laser desorption/ionization time-of-flight mass spectrometry. Results: Marinating turkey meat in buttermilk and whey compared to marinating in lemon juice and the control sample resulted in a higher (p<0.05) degree of yellow color saturation (b^*) and a reduction (p<0.05) in the number of mesophilic aerobic bacteria, Pseudomonas spp. and Enterobacteriaceae family as well as the number of identified mesophilic aerobic bacteria in both raw and roasted samples. The lowest (p<0.05) shear force values were found in products marinated in whey. Conclusion: The use of buttermilk and acid whey as a marinade for meat increases the microbiological safety of the product compared to marinating in lemon juice, while maintaining good technological features of the product.

• Journal of Microbiology and Biotechnology
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• v.17 no.8
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• pp.1330-1337
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• 2007

To better understand the gene expression of the cold-adapted polar diatom, we conducted a survey of the Chaetoceros neogracile transcriptome by cDNA sequencing and expression of interested cDNAs from the Antarctic diatom. A non-normalized cDNA library was constructed from the C. neogracile, and a total of 2,500 cDNAs were sequenced to generate 1,881 high-quality expressed sequence tags (ESTs) (accession numbers EL620615-EL622495). Based on their clustering, we identified 154 unique clusters comprising 342 ESTs. The remaining 1,540 ESTs did not cluster. The number of unique genes identified in the data set is thus estimated to be 1,694. Taking advantage of various tools and databases, putative functions were assigned to 939 (55.4%) of these genes. Of the remaining 540 (31.9%) unknown sequences, 215 (12.7%) appeared to be C. neogracile-specific since they lacked any significant sequence similarity to any sequence available in the public databases. C. neogracile consisted of a relatively high percentage of genes involved in metabolism, genetic information processing, cellular processes, defense or stress resistance, photosynthesis, structure, and signal transduction. From the ESTs, the expression of these putative C. neogracile genes was investigated: fucoxanthin chlorophyll (chl) a,c-binding protein (FCP), ascorbate peroxidase (ASP), and heat-shock protein 90 (HSP90). The abundance of ASP and HSP90 changed substantially in response to different culture conditions, indicating the possible regulation of these genes in C. neogracile.