• Korean Journal of Soil Science and Fertilizer
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• v.24 no.1
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• pp.69-76
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• 1991

A pot experiment was conducted to find out the effects of lime and phosphate application on the changes of number of soil microorganisms, indigenous Rhizobium japonicum, nodule formation, and ureide-and amide-N in leaf and stem exudate of soybean plant under uncultivated hillside red earth in very low pH value, organic matter, available phosphate, and cation exchange capacity. The results obtained were summarized as follows : 1. The plant height, stem length, root dry weight and nodule weight were significantly increased with the application of lime and phosphate application than that of control plot. 2. The concentration of amide-N in soybean plant at the 45 days after sowing was obtained as high in order of control>lime> lime+phosphate while the concentration was obtained in order of Iime+phosphate>lime> control at flowering stage 3. However, concentration of ureide-N in the soybean leaf at the 45 days after sowing was obtained as high in order of control>lime>lime+hosphate while reversed concentration was obtained in stem. 4. The number of soil microorgan isms were increased with increase of pH value, available phosphate and soil exchangeable cation. 5. Significantly negative high correlation were obtained with the concentration of Al, Fe in soil and the concentration of amide-and ureide-N in soybean plant at flowering stage while positive correlation was obtained with plant growth and the concentration of ureide-N.

• Journal of the Korean Society of Food Science and Nutrition
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• v.38 no.1
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• pp.70-75
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• 2009

For the effective use of salmon processing by-products, the food components of muscle around pectoral fin (MAPF) were investigated and compared with those of salmon fillet muscle (SFM). The proximate composition of MAPF was 64.4% for the moisture, 17.2% for the crude protein, 16.2% for the crude lipid and 1.4% for the ash. The pH, volatile basic nitrogen (VBN) content and yield of MAPF were 6.73, 7.8 mg/100 g and 7.4 (g/100 g SFM), respectively. The trichloroacetic acid (TCA) soluble-N content of MAPF was 479 mg/100 g, which was lower than that (612 mg/100 g) of SFM. The Hunter value of MAPF was 54.86 for L value, 22.08 for a value, 22.41 for b value and 52.35 for ${\Delta}$E value, which were similar to those of SFM. The total content in amino acids of MAPF was 17.1 g/100 g, its major amino acids were aspartic acid, glutamic acid, leucine and lysine. The major fatty acids of MAPF were 16:0, 18:1n-9 and 18:2n-6, 20:5n-3 and 22:6n-3. No differences were found in the major fatty acids and the major amino acids between MAPF and SFM. The calcium and phosphorus contents of MAPF were 19.1 mg/100 g and 211.7 g/100 g, respectively. These results suggested that MAPF could be used as seafood resources.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.21 no.1
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• pp.21-29
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• 1988

This study was carried out to develop the powdered Katsuobushi (a kind of boiled, smoked, and dried fish product which is used for seasoning soup as it is.) using skipjack as a natural flavoring substance. The processing conditions of the powdered Katsuobushi and the changes of taste compounds during processing of the products were examined. In preparation of the powdered Katsuobushl, frozen skipjack was thawed, beheaded, gutted, filleted and then sliced to 1cm of thickness. The silted meats were boiled in skipjack extract for 20 minutes, and then it was smoked for, 3 times to $10\~12\%$ moisture content at $80^{\circ}C$ for 8 hours. The smoked - dried meats were followed to be 50 mesh of particle size. The effect of slicing and boiling in skipjack meat extract on enhancing flavor and on preventing lipid oxidation of product during processing were observed. The moisture content and crude lipid content of the powdered Katsuobushi was in the range of 11 to $12\%$ and 4.3 to $4.8\%$, respectively. The taste compounds of the product were nucleotides and their related compounds, 1135.8mg/100g ; free amino acid and related compounds, 2210.2mg/100g ; non-volatile organic acids, 1148.0mg/100g ; and total creatinine. 592.1mg/100g on dry basis, and small amount of betaine and TMAO. The major elements of mineral in the product were found to be K, Mg, Na, and Ca. The content of IMP was 542.0mg/100g, and major free amino acids were found to be histidine, anserine, taurine, carnosine and alanine of which occupied to $83.6\%$ of total free amino acids. In non -volatile organic acids, major ones were lactic acid, succinic acid, pyroglutamic acid and $\alpha-ketoglutaric$ acid. From the results of the chemical experiments and sensory evaluation, we may conclude that the flavor of the product from present experiment is more desirable than that of conventional products although the processing time used were much shortened than that of conventional method, and it can be commercialized as a seasoning powder.

• Journal of Food Hygiene and Safety
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• v.13 no.4
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• pp.319-331
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• 1998

The purposes of this study were to develop Hazard Analysis Critical Control Point plan applicable to cook/chilled Pork Bulkogi (broiled sliced pork with sauces) in school foodservice operations and to establish reasonable shelf-life limits by assessing food quality during chilled storage period of 5 days. During the product flow, time-temperature profile was recorded and microbiological analyses including mesophilic and psychrotrophic total plate counts, coliform, and fecal coliform and qualitative analyses of Salmonella and Listeria monocytogenes were done. Chemical analyses (pH, acid value, total volatile basic nitrogen), sensory evaluation, and quantitative analysis of thiamin were conducted for 5 days of chilled storage. The number of mesophiles in raw pork ($4.26{\pm}0.11\;Log\;CFU/g$), seasoning mixture ($5.97{\pm}O.04\;Log\;CFU/g$) and marinated pork ($5.56{\pm}0.21\;Log\;CFU/g$) were below the microbial standards for "requires further cooking" food items. Listeria monocytogenes was detected in seasoning mixture. After heating, the number of mesophiles ($5.17{\pm}0.04\;Log\;CFU/g$) were slightly reduced but it did not meet the microbial guidelines of $5\;Log\;CFU/g$ for "ready-to-eat" foods. No other microbes including pathogens were detected. By reheating the menu item after chilled storage, the number of mesophiles were reduced in every phase of 1st day ($4.62{\pm}0.22\;Log\;CFU/g$), 3rd day ($4.55{\pm}0.20\;Log\;CFU/g$) and 5th day ($4.25{\pm}0.16\;Log\;CFU/g$) of chilled storage, and the number of microbes was below the standard limits for "ready-to-eat" foods. At the fifth day of chilled storage, pH (p<0.05), acid value (p<0.01) and TVBN (p<0.05) showed significant increases. Sensory evaluation results did not show any significant change for 5 days of chilled storage. Thiamin content showed a decrease for 5 days of chilled storage. Consequently, the ideal shelflife recommended for Pork Bulkogi was within 3 days of chilled storage. CCPs for Pork Bulkogi were purchasing and receiving of raw meat and some seasoning ingredients, heating, chilling, chilled storage, reheating, and distribution.

• Journal of Life Science
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• v.25 no.12
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• pp.1408-1414
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• 2015

In this study, to retain a stable bacterial inoculant, Bacillus strains showing antifungal activity were screened. The improved production, antifungal mechanism, and stability of the antifungal metabolite by a selected strain, AF4, a potent antagonist against phytopathogenic Botrytis cinerea, were also investigated. The AF4 strain was isolated from rhizospheric soil of hot pepper and identified as Bacillus subtilis by phenotypic characters and 16S rRNA gene analysis. Strain AF4 did not produce antifungal activity in the absence of a nitrogen source and produced antifungal activity at a broad range of temperatures (25-40℃) and pH (7-10). Optimal carbon and nitrogen sources for the production of antifungal activity were glycerol and casein, respectively. Under improved conditions, the maximum antifungal activity was 140±3 AU/ml, which was higher than in the basal medium. Photomicrographs of strain AF4-treated B. cinerea showed morphological abnormalities of fungal mycelia, demonstrating the role of the antifungal metabolite. The B. subtilis AF4 culture exhibited broad antifungal activity against several phytopathogenic fungi. The antifungal activity was heat-, pH-, solvent-, and protease-stable, indicating its nonproteinous nature. These results suggest that B. subtilis AF4 is a potential candidate for the control of phytopathogenic fungi-derived plant diseases.

• Microbiology and Biotechnology Letters
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• v.33 no.2
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• pp.96-105
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• 2005

For screening of autoregulator receptor gene from Streptomyces longwoodensis, PCR was performed with primers of receptor gene designed on the basis of amino acid sequences of autoregulator receptor proteins with known function. PCR products were subcloned into the BamHIsite of pUC19 and transformed into the E. coli $DH5{\alpha}$. The isolated plasmid from transformant contained the fragment of 100 bp, which was detected on $2\%$ gel after BamHI treatment. The insert, 100 bp PCR product, was confirmed as the expected internal segment of gene encoding autoregulator receptor protein by sequencing. Southern and colony hybridizations with the 100 bp fragment as a probe allowed to select a genomic clone of S. longwoodensis, pSLT harboring a 4.4 kb SphI fragment. Nucleotide sequencing analyses revealed a 651 bp open reading frame(ORF) were isolated protein showing moderate homology ($35{\sim}46\%$) with the ${\Gamma}$-butyrolactone autoregulator receptors from Streptomyces sp., and this ORF was named sltR The sltR/pET-17b plasmid was constructed to overexpress the recombinant SltR protein (rSltR) in E. coli BL21 (DE3)/pLysS, and the rSltR protein was purified to homogeneity by DEAE-Sephacel column chromatography, and DEAE-5PW chromatography (HPLC). The molecular mass of the purified rSltR protein was 55 kDa by HPLC gel-filtration chromatography and 28 kDa by SDS-PAGE, indicating that the rSltR protein is present as a dimer. A binding assay with tritium-labeled autoregulators revealed that the rSltR has clear binding activity with a A-factor type autoregulator as the most effective ligand.

• Journal of Life Science
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• v.27 no.2
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• pp.202-210
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• 2017

As an effort to find a potential biopreservative, we isolated bacterial strains producing bacteriocin from fermented foods. A strain was finally selected and characteristics of the bacteriocin were investigated. The selected strain was identified as Bacillus subtilis E9-1 based on the 16S rRNA gene analysis. The culture supernatant of B. subtilis E9-1 showed antimicrobial activity against Gram-positive bacteria. Subtilisin A, ${\alpha}$-chymotrypsin, trypsin and proteinase K inactivated the antimicrobial activity, which means its proteinaceous nature, a bacteriocin. The bacteriocin activity was fully retained at the pH range from 2.0 to 8.0 and stable at up to $100^{\circ}C$ for 60 min. Solvents such as ethanol, isopropanol and methanol had no effect on the antimicrobial activity at the concentration of 100% but acetone and acetonitrile reduced the activity at up to 100% concentration. Cell growth of four indicator strains was dramatically decreased in dose-dependent manner. Listeria monocytogenes was the most sensitive, but Enterococcus faecium was the most resistant. Bacillus cereus and Staphylococcus aureus showed the medium sensitivity. The bacteriocin showed its antimicrobial activity against B. cereus and L. monocytogenes via bactericidal action. The number of viable cells of L. monocytogenes started to reduce after addition of bacteriocin to the minced beef. The bacteriocin was purified through acetone concentration, gel filtration chromatography and RP-HPLC. The whole purification step led to a 6.82 fold increase in the specific activity and 6% yield of bacteriocin activity. The molecular weight of the purified bacteriocin was determined to be 3.3 kDa by MALDI-TOF/TOF mass spectrometry.

• Journal of Fisheries and Marine Sciences Education
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• v.23 no.3
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• pp.410-424
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• 2011

This study was investigated for the purpose of obtaining basic data which can be applied to processing of canned sea mussel using tomato paste. Shell were washed, and then steamed and shucked. Sea mussel meat was prepared with ratio of sea mussel 90g, tomato paste sauce 65g(tomato paste 42%, gum guar 1.0%, salt 2.0%, starch syrup 2.0%, cooking wine 1%, water 52%). The sea mussel meats were packed with vacuum seamer in 301-3 can, and then sterilized for various F0 value(F0 8-12 min.) in a steam system retort at $118^{\circ}C$. The factors such as pH, VBN, amino-N, total amino acid, free amino acid, chemical composition, color value (L, a, b), texture profile, TBA value, mineral, sensory evaluation and viable bacterial count of the canned sea mussel produced with various sterilization condition(F0 8-12 min.) were measured. The same element was also measured during preservation. The results showed that the product sterilized at F0 8 min. and preserved for 90 days were the most desirable.

• The Korean Journal of Food And Nutrition
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• v.16 no.4
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• pp.328-333
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• 2003

When the extract of the medicinal plants, Kaempferia galanga L., Zanthoxylum bungeanum, Eugenia caryophyllata, Foeniculum vulgare, was added to Naengmyeon broth with the concentration of 0.1% and 0.3% each, its effect during the preservation time of broth was investigated. pH of the extract-added broth was lower than control at the initial, but higher after 72 hours of preservation, which showed that when it added 0.1% and 0.3% of extract to the broth, pH of Kaempferia galanga L. was 4.92 and 5.08 respectively, whereas control was 4.60. Titratable acidity was lowered after 48 hours and also Kaempferia galanga L. showed the lowest acidity with 0.66 for adding 0.1% of its extract and 0.55 for 0.3% of adding, but control was 0.89 at the time of 90 hours of preservation, and then it showed to be lowered in the order of Zanthoxylum bungeanum, Eugenia caryophyllata and Foeniculum vuigare. Turbidity of each broth added the extracts of four of the medicinal plants was 7.5∼7.9 and 7.9∼8.2, respectively for 0.1% and 0.3% of concentration at the initial, but it began to lower and 90 hours later it was 8.8∼9.5 and 8.7∼9.0 respectively, whereas control was 10.8. Total viable cells(TVC) and coliform bacteria(CB) were increased with great at the 72 hours of preservation time, and Kaempferia galanga L. was the most effective, which when control was 4.8${\times}$10 CFU/ml at 72 hours, TVC was 1.7${\times}$10 CFU/ml for the addition of 0.1% of extract and 0.9${\times}$10 CFU/ml for 0.3%. CB was 3.2${\times}$10 CFU/ml for 0.1% and 1.7${\times}$10 CFU/ml for 0.3% respectively and 6.0 ${\times}$ 10 CFU/ml for control at the time of 72 hours, and it was lowered in the order of Zanthoxylum bungeanum, Eugenia caryophyllata and Foeniculum vulgare. Volatile basic nitrogen content detected that control was 2.67mg% at first, and then increased to 3.96mg% at 90 hours of preservation, but the broth added with the extract of Kaempferia galanga L. was 2.58mg% for 0.1% and 2.47mg% for 0.3% at the initial, and at 90 hours it was 3.64mg% and 3.33mg% respectively. The results of adding the extracts of four medicinal plants for the improvement of the preservation time of Naengmyeon broth, were that the most effective medicinal plant was Kaempferia galanga L. and the antimicrobial activity of the medicinal plant extracts for Naengmyeon broth was highly effective after 3 days of preservation time.

• Food Science and Preservation
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• v.22 no.1
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• pp.36-43
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• 2015

The edible crab is among the rich resources that can be used as materials for food products, but living crabs and crabs marinated in soy sauce are the only widely utilized materials for food products. For seafood development, research is needed to promote the use of crabs in various products. In this study, the quality changes of fried rice prepared with crab meat, crab emulsion sauce and crab cooker effluent were investigated. The pH and acidity values did not show any significant difference at $-20^{\circ}C$. The acidity of the fried rice continuously increased during storage at 4 and $25^{\circ}C$. The VBN and TBA values of the fried rice stored at 4 and $25^{\circ}C$ were significantly higher than those of the fried rice stored at $-20^{\circ}C$ during the storage period. The viable cell count of the fried rice stored at $-20^{\circ}C$ changed little during the storage period while that of the fried rice stored at 4 and $25^{\circ}C$ rapidly increased over 2 weeks. For the fried rice stored at $-20^{\circ}C$, the overall quality did not show significant differences during the storage period. In conclusion, the best storage temperature for both quality and safety was found to be $-20^{\circ}C$. At such storage temperature, the quality of the stored instant rice using crab meat did not change, and through research the expanding possibilities of using crab materials were confirmed.