• Korean Journal of Food Science and Technology
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• v.40 no.6
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• pp.643-648
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• 2008

The principal objective of this study was to evaluate the effects of the addition of sourdough to bread dough, specifically with regard to the physicochemical characteristics of bread dough, organoleptic evaluation, and bread storage. Marked increases in lactic acid bacterial counts $10^{9-10}CFU/g$ in dough samples with 30, 50, and 100% of added sourdough to the respective bread dough were observed after the first fermentation period of the dough, but decreases were observed in yeast cells. The highest overall acceptance scores were recorded for the 100% sourdough-added bread, and almost no differences in taste and texture were detected between the regular bread (control bread) and sourdough-added bread on the sensory evaluations, with slightly lower evaluation scores (for sour taste) in the sourdough-added bread. The sourdoughadded bread also showed retarded mold growth in the bread on our storage tests. Six days had elapsed prior to the appearance of mold growth in the sourdough-added bread, whereas three days elapsed in the regular bread. The more sourdough was added to the dough, the less was the total count in bread. Increases of 13.1, 20.9, and 36.2% in the retardation of starch retrogradation of the bread were observed as the result of additional increases in sourdough quantity to bread at 30, 50, and 100%, respectively.

• Korean journal of food and cookery science
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• v.29 no.5
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• pp.599-603
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• 2013

Tarak is our own traditional fermented milk made through lactic acid fermentation by using makgeolli as inoculum for milk or using already made tarak as inoculum but it is hardly known to people as its related studies are also insufficient. Accordingly, the purpose of this study was to manufacture jelly by using tarak and analyze its quality characteristics for the diversification of consumption promotion and demand of traditional fermented milk tarak. Tarak jelly that was made according to the percentage of adding tarak showed a tendency that the content of crue protein, crude fat and crude ash except for moisture water meaningfully increased as the amount of tarak added increased (P<0.05). In the case of pH, it declines as the amount of tarak added was high. The chromaticity measurement result of tarak jelly was 54.32 in the case of control group for L, and it increased as the amount of tarak added increased. In the case of a, it decreased as tarak was added, whereas b meaningfully increased. There was meaningful difference between samples in the case of chewiness, fracturability and adhesiveness (p<0.05). The sensory test result showed that there was meaningful difference between samples in their appearance and taste but there was no meaningful difference in the case of overall preference, scent and texture.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.16 no.8
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• pp.5343-5350
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• 2015

This study aims to compare and analyze the antioxidant effect of Cheonggukjang's traditional fermentation strain, Bacillus subtilis NG24 which was a control of the study, in order to see the biological activity effect of the new strain, Bacillus amyloliquefaciens NBF11-1 that was first found in the surface of the bamboo stem, but hasn't been insufficiently researched. In the antioxidant activity experiment of the Cheonggukjang extract, the B.amyloliquefaciens NBF11-1 sample showed a significant increase in the total polyphenol extract content, compared to B.subtilis NG24(p=0.032). Also, compared to B.subtilis NG24, the sample containing B.amyloliquefaciens NBF11-1 showed a significant increase in SOD-like Activity, DPPH radical scavenging, and NO radical scavenging, as the concentration rose(p<.05). Additionally, $IC_{50}$ in each antioxidant activity experiment significantly decreased in the B.amyloliquefaciens NBF11-1 sample like SOD-like Activity(p=0.045), DPPH radical scavenging(p=0.041), and NO radical scavenging(p=0.019), compared to B.subtilis NG24.

• Food Science and Preservation
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• v.8 no.4
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• pp.434-441
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• 2001

The purpose of this research is the establishment of optimal processing and the quality improvement of confectionary analysis of the damaged starch content of flour. I studied the rheological and bread making properties of the dough containing different damaged starch content. I examined rheological and physico- chemical characteristic farinograph, extensograph and amylograph with DNS, CWRS and SW containing 6.5%, 8.2%, 9.0%, 9.0% and 10.5% of damaged starch. And I measured the hardness and specific volume and performed the functional survey by rheometer for quality control. In the amylogram, at the damaged starch content 9.5% at such the maximum viscosity was 900 B.U. the volume of bread fermention tolerance were increased. In addition, the extensegram after 135 min showed that maximum resistance of the dough were 570 B.U at the damaged starch contents of 9.5% and the bread had homogeneous air cells and internal structures at the damaged starch contents of 9.5% at which the area(A), resistance(R) and R/E value of the dough were highest.

• Food Science and Preservation
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• v.7 no.3
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• pp.321-325
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• 2000

This study was conducted to investigate the effect of the extracts (water, 70% ethanol and ethylacetate) from dandelion (Traxancum platycarpum D.) leaf and root on the inhibitory activities of Leuconostoc mesenteroides, Lactobacillus brevis, Lactobacillus plantarum and Lactobacillus acidophilus. And also, the amounts of gas formation from kimchi with different concentration of the ethylacetate extracts (EE) were analyzed. EE of dandelion leaf inhibited the growth of Leuc. mesenteroides and L. acidophilus, and L. brevis by 50 and 33% at concentration of 0.5%, respectively. But no affected in L. plantarum estimated by pH, acidity, turbidity and clear zone. And no difference was founded in leaf and root. Gas was formed from the soaking day to 5-6 days of fermentation at $20^{\circ}C$, and the accumulated gas volumes were 80 ml/100 g in control, 30 ml/100 g in 0.5% EE, 8 ml/100 g in 1.0% EE.

• Journal of Microbiology and Biotechnology
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• v.24 no.11
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• pp.1516-1524
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• 2014

Flavin adenine dinucleotide-dependent glucose dehydrogenase (FAD-GDH) can utilize a variety of external electron acceptors and also has stricter substrate specificity than any other glucose oxidoreductases, which makes it the ideal diagnostic enzyme in the field of glucose biosensors. A gene coding for a hypothetical protein, similar to glucose oxidase and derived from Aspergillus terreus NIH2624, was overexpressed in Pichia pastoris GS115 under the control of an AOX1 promoter with a level of 260,000 U/l in the culture supernatant after fed-batch cultivation for 84 h. After a three-step purification protocol that included isopropanol precipitation, affinity chromatography, and a second isopropanol precipitation, recombinant FAD-GDH was purified with a recovery of 65%. This is the first time that isopropanol precipitation has been used to concentrate a fermentation supernatant and exchange buffers after affinity chromatography purification. The purified FAD-GDH exhibited a broad and diffuse band between 83 and 150 kDa. The recombinant FAD-GDH was stable across a wide pH range (3.5 to 9.0) with maximum activity at pH 7.5 and $55^{\circ}C$. In addition, it displayed very high thermal stability, with a half-life of 82 min at $60^{\circ}C$. These characteristics indicate that FAD-GDH will be useful in the field of glucose biosensors.

• Journal of Microbiology and Biotechnology
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• v.23 no.3
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• pp.382-389
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• 2013

Propionate is an important intermediate product during the methane fermentation of organic matter, and its degradation is crucial for maintaining the performance of an anaerobic digester. In order to understand the effect of temperature on propionate degradation, an upflow anaerobic sludge blanket (UASB) reactor with synthetic wastewater containing propionate as a sole carbon source was introduced. Under the hydraulic retention time (HRT) of 10 h and influent propionate of 2,000 mg/l condition, propionate removal was above 94% at 30-$35^{\circ}C$, whereas propionate conversion was inhibited when temperature was suddenly decreased stepwise from $30^{\circ}C$ to $25^{\circ}C$, to $20^{\circ}C$, and then to $18^{\circ}C$. After a long-term operation, the propionate removal at $25^{\circ}C$ resumed to the value at 30- $35^{\circ}C$, whereas that at $20^{\circ}C$ and $18^{\circ}C$ was still lower than the value at $35^{\circ}C$ by 8.1% and 20.7%, respectively. Microbial community composition analysis showed that Syntrophobacter and Pelotomaculum were the major propionate-oxidizing bacteria (POB), and most POB had not changed with temperature decrease in the UASB. However, two POB were enriched at $18^{\circ}C$, indicating they were low temperature tolerant. Methanosaeta and Methanospirillum were the dominant methanogens in this UASB and remained constant during temperature decrease. Although the POB and methanogenic composition hardly changed with temperature decrease, the specific $COD_{Pro}$ removal rate of anaerobic sludge (SCRR) was reduced by 21.4%-46.4% compared with the control ($35^{\circ}C$) in this system.

• Environmental Engineering Research
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• v.24 no.4
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• pp.670-679
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• 2019

Lignin complexity molecule makes its biodegradation difficult during lignocellulosic wastes composting. So, the improvement of its biodegradation has usually been considered as an objective. This study aimed to determine the impact of Trametes trogii inoculation on organic matter and particularly on lignin and cellulose during green wastes co-composting with olive mill waste water sludge and coffee grounds. Three types of heaps (H1, H2 and H3) were investigated during 180 d. H3 and H2 were inoculated at the beginning of the process (t₀) and 120 d later (t₁₂₀), respectively while H1 was the control. Results showed the absence of pH stabilization in H3 during the first month. Also, in this period we observed a faster degradation of some easily available organic matter in H3 than in the other heaps. After 120 d, a better cellulose decomposition (25.28%) was noticed in H3 than in H1 and H2 (16%). Inoculation during the second fermentation phase induced supplementary lignin degradation in H2 with a percentage of 35% against 23 and 26% for H1 and H3, respectively. For all the runs, a Fourier Transform Infrared analysis showed aliphatic groups' decrease, OH groups' increase and lignin structural modification.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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• 2018.10a
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• pp.444-447
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• 2018

Baculovirus expression systems have many known advantages including fast and cost-effective methods to generate large amounts of recombinant proteins in comparison to bacterial expression systems, particularly those requiring complex post-translational modifications. Especially, recombinant baculoviruses can transfer their vectors and express their recombinant proteins in a wide range of mammalian cell types. In this study, baculoviral vectors which were reconstructed from pcDNA3.1 vector, were recombined with cytomegalovirus (CMV) promoter,uroplakin II promoter, polyhedron promoter, vesicular stomatitis virus G (VSVG), enhanced green fluorescent protein (EGFP), and protein transduction domain (PTD). These recombinant vectors were infected with various cells and cell lines. The baculovirus vector thus developed was analyzed by comparing the metastasis and expression of the recombinant genes with conventional vectors. These results suggest that the baculovirus vector has higher efficiency in metastasis and expression than the control vector.

• Journal of Environmental Health Sciences
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• v.34 no.3
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• pp.207-212
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• 2008

This study was performed to investigate the anti-microbial activity of extract from Korean fermented soybean paste (doen-jang) against 16 types of oral microbes, and to determine the minimum inhibition concentration (MIC) of the extract for three major microbes causing human oral diseases (Streptococcus mutans, Porphyromonas gingivalis, and Candida albicans). The extract was prepared using ethyl acetate and it was treated with the oral microbes at a concentration of 5.00 mg/ml (0.5%). The anti-microbial activity and MIC were measured using broth dilution method. Significant reduction of microbial activities of 16 types of oral microbes occurred when the soybean paste extract was added to the broth compared to the control (p<0.01), and striking inhibition (more than 99%) was observed in ten types. S. mutans, which causes dental caries, showed MIC at a concentration of 1.25 mg/ml for the extract. P. gingivalis, which causes adult periodontal disease, showed MIC at a concentration of 2.50 mg/ml for the extract. C. albicans, which causes denture stomatitis and angular stomatitis, showed MIC at a concentration of 20 mg/ml for the extract. These results indicate that ethyl acetate extract of doen-jang showed strong anti-microbial effect against 16 types of oral microbes, and the anti-microbial effect of the extract against oral microbes was stronger against bacteria than against fungi. The anti-microbial effect might be possibly enhanced by the fermentation of soybeans.