• The Journal of the Korean Society for Microbiology
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• v.8 no.1
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• pp.7-11
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• 1973

The authors identified eighty-eight Shigella cultures among about four thousands specimens collected from all over the country in 1972. Of eighty-eight cultures, seventy-seven cultures belonged to Shigella flexneri and eleven cultures to Shigella sonnei. None of cultures belonging to either subgroup A or C was detected in 1972. Of seventy-seven cultures of Shigella flexneri one was $B_{1b}$, fifty-six were $B_{2a}$, nine were $B_{3a}$, six were $B_{4a}$, three were By and one was each of $B_{3b}$ and $B_{3c}$. Of eleven cultures of Shigella sonnei seven cultures appeared to be phase I and the others phase II. Although there was quite a difference found in the incidence of isolating Shigella organisms between different areas as shown in Table 1, it would not be possible to understand that there might not have been the cases or carriers of Shigella in the areas where the organisms were not isolated in 1972. Concerning the biochemical properties it was not possible to compare the results obtained from the decarboxylase and dihydrolase tests with them obtained in previous years except that of lysine decarboxylase tests since they were not reported individually by the different serotypes in the previous reports. These results obtained in 1972 would be the data for the future comparison. In regards to the antibiotics-sensitivity of Shigella cultures the most of them showed sensitive results to nitrofurantoin, ampicillin, cephalosporin, gentamycin and geopen, and the majority of them appeared to be resistant to cloxacillin, tetracycline and streptomycin by means of the In Vitro tests.

• The Korean Journal of Food And Nutrition
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• v.18 no.4
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• pp.349-356
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• 2005

For the purpose of making a new type of functional drinkable yoghurt, skim milk containing $0.5\~2.0\%$(w/v) green tea powder was fermented by the mixed stains of Streptococcus thermophilus and Lactobacillus acidophilus. Quality characteristics of the drinkable yoghurts were evaluated in terms of quality-keeping properties(number of viable cells, pH, titratable acidity) and sensory properties. When the drinkable yoghurts added with $0.5\~2.0\%$ green tea powder were kept at $4^{\circ}C\;and\;20^{\circ}C$ for 20 days, the number of viable cell counts of the lactic acid bacteria($2.1\times10^8\~6.2\times10^8$ CFU/mL). pH($4.16\~4.22$) and titratable acidity($0.792\~0.881\%$) were not significantly changed for all drinkable yoghurts during the storage at $4^{\circ}C\;and\;20^{\circ}C$ days, but the number of viable cell counts($4.2\times10^3\~1.8\times10^5$ CFU/mL), pH($3.82\~3.92$) and titratable acidity($1.057\~1.174\%$) were markedly changed f3r the storage at $20^{\circ}C$ for 20 days. Therefore the keeping quality of the drinkable yoghurts with addition of green tea powder was relatively good at $4^{\circ}C$ for 20 days. The results of sensory evaluation of the drinkable yoghurts containing peen tea powder indicated that flavor, sweet taste, mouthfeel and aftertaste of the drinkable yoghurt with $0.5\%$ green tea powder showed higher preference than others. And the drinkable yoghurt containing $0.5\% green tea powder added $20\%$(v/v) oligosaccharide had the higher sensory scores in sweet taste, aftertaste and overall acceptability among the treatments.

• Korean Journal of Food Science and Technology
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• v.34 no.3
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• pp.449-453
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• 2002

This was studied to evaluate the quality characteristics of the bread added chitosan during storage at room temperature(Temp. $27^{\circ}C{\pm}2$, RH $75%{\pm}10$). The volume of the dough was increased depending on the larger molecular weight and the higer concentration of chitosan but was decreased at 0.50% of 120 kDa chitosan. The water activity was low depending on the larger molecular weight and the higher concentration of chitosan at the early storage, but maintained constantly during storage totally. The colors of the bread was hardly affected by 30 kDa of chitosan. Textural characteristics was improved at 30 kDa and 120 kDa of chitosan. Especially, the change of the hardness were maintained lower at 30 kDa, 120 kDa of chitosan during storage than that of standard. These results showed that the quality of the bread by added 30 kDa of chitosan was improved highly.

• Korean Journal of Soil Science and Fertilizer
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• v.40 no.2
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• pp.156-163
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• 2007

This study was conducted to evaluate the liquefying efficiency of mixed organic fertilizer in different conditions. The organic fertilizer was composed of sesame oil cake, rice bran, fish meal, ground bone meal etc, and made by fermenting process. It included $23g\;kg^{-1}$, $17.0g\;kg^{-1}$, $23.9g\;kg^{-1}$, $290g\;kg^{-1}$ of N, $P_2O_5$, $K_2O$, organic matter, respectively. In one test, the mixed organic fertilizer was added in the proportion of 10% to water 90% and aerated continuously, for 2, 8 hours per day, and not aerated as control. In the other test, ratios of organic fertilizer to water were 5%, 10%, 20% and aerated for 2 hours a day. With the increase of liquefying time, pH, EC and $NH_4-N$ increased without relation to aeration time. After 10 days, liquid organic fertilizer aerated for 2 hours a day contained $634mg\;N\;kg^{-1}$, $68.1mg\;P_2O_5\;kg^{-1}$, $453mg\;K_2O\;kg^{-1}$, which was not significantly different from 8 hours a day or continuous aeration. Then extraction ratios of inorganic contents were 27.6%, 4.0% and 18.9%, respectively. Continuous aeration resulted in increasing the viable number of aerobic bacteria, spore forming bacteria and fungi in liquefied solution. Higher ratio of organic fertilizer to water increased EC, $NH_4-N$ and other inorganic matter contents, but decreased extraction ratio of nutrients in liquid fertilizer. The liquid organic fertilizer of 20% contained $1,140mg\;N\;kg^{-1}$, $35.4mg\;P_2O_5\;kg^{-1}$, $544mg\;K_2O\;kg^{-1}$ after 10 days. Then extraction ratios were 24.8%, 2.4% and 13.6%, respectively. The ratio of organic fertilizer to water was positively correlated with only spore forming bacteria, Pseudomonas spp. among microorganisms.

• Korean Journal of Breeding Science
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• v.42 no.6
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• pp.690-694
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• 2010

A new soybean cultivar for soy-paste, 'Daeyang', was developed from the cross among 'Jangyeobkong', 'Hwaeomputkong' and 'Suwon192' by the soybean breeding team at the National Institute of Crop Science (NICS) in 2007. A promising line, SS97214-80-1, was selected and named this line 'Milyang163'. It was prominent and had good result from regional adaptation yield trials (RYT) for three years from 2005 to 2007 and released as the name of 'Daeyang'. It has a determinate growth habit, purple flower, grey pubescence, yellow seed coat, yellow hilum, large spherical seed (25.2 g per 100 seeds). 'Daeyang' is resistant to soybean mosaic virus and moderately resistant to bacterial pustule, the major soybean disease in Korea. The average yield of 'Daeyang' was 2.58 ton per hectare in the regional yield trials (RYT) carried out for three years from 2005 to 2007 which was 3 percent higher than the check variety, 'Taekwang'.

• Korean Journal of Agricultural and Forest Meteorology
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• v.20 no.4
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• pp.348-356
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• 2018

Most of fires were human-caused fires in Korea, but meteorological factors are also big contributors to fire behavior and its spread. Thus, meteorological factors as well as topographical and forest factors were considered in the fire danger rating systems. This study aims to develop an advanced national integrated daily weather index(DWI) using weather data in the spring and fall to support forest fire prevention strategy in South Korea. DWI represents the meteorological characteristics, such as humidity (relative and effective), temperature and wind speed, and we integrated nine logistic regression models of the past into one national model. One national integrated model of the spring and fall is respectively $[1+{\exp}\{-(2.706+(0.088^*T_{mean})-(0.055^*Rh)-(0.023^*Eh)-(0.014^*W_{mean}))\}^{-1}]^{-1}$, $[1+{\exp}\{-(1.099+(0.117^*T_{mean})-(0.069^*Rh)-(0.182^*W_{mean}))\}^{-1}]^{-1}$ and all weather variables significantly (p<0.01) affected the probability of forest fire occurrence in the overall regions. The accuracy of the model in the spring and fall is respectively 71.7% and 86.9%. One integrated national model showed 10% higher accuracy than nine logistic regression models when it is applied weather data with 66 random sampling in forest fire event days. These findings would be necessary for the policy makers in the Republic of Korea for the prevention of forest fires.

• Journal of Life Science
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• v.31 no.5
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• pp.475-480
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• 2021

Interest in edible insects such as Protaetia brevitarsis has increased rapidly, and several insect producers use these insects in industrialized mass production. However, mass rearing of insects can cause insect diseases. Sprouted barley is a valuable source of nutrients and has antioxidant, antimicrobial, anti-inflammatory, and anti-cancer effects. This study was conducted to investigate the effect of sprouted barley as a feed additive for producing healthy P. brevitarsis larvae. P. brevitarsis larvae were fed feeds with or without sprouted barley, and their body weight and larval period wewe checked weekly. To confirm the antibacterial effects of sprouted barley, in vitro bioassays were performed by counting Serratia marcescens colonies, and in vivo bioassays were performed by determining the survival rate and body weights of the S. marcescens-infected larvae. Larvae fed different feeds were analyzed for their nutrient compositions (i.e., such as proximate composition, minerals, amino acids, and heavy metals). Larvae fed 5% and 10% sprouted barley had maximum weight increases of 19.2% and 23.1%, respectively. Both treatment groups had significantly shorter larval periods than those of the control group. Sprouted barley markedly inhibited the growth of entomopathogenic S. marcescens. Furthermore, larvae fed sprouted barley exhibited higher Cu, Zn, and K levels. Seventeen amino acids were present in larvae fed sprouted barley, of which, tyrosine and glutamic acid were predominant. No heavy metals were detected in any of the investigated groups. Therefore, sprouted barley may be a suitable feed additive for producing high-quality P. brevitarsis larvae.

• Journal of Life Science
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• v.32 no.12
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• pp.971-978
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• 2022

Sulfur-oxidizing, ammonium-oxidizing, and nitrogen-oxidizing media were used to isolate bacteria to degrade malodor gas effectively in piggery manure or soil. Twelve different strains were isolated: Paenibacillus amylolyticus, Rhodococcus jostii, Rhodococcus qingshengii, Rhodococcus opacus, Alcaligenes faecalis, Alcaligenes faecalis, Kastia adipate, Kastia adipata, Microbacterium oxydans, Halomonas campisalis, Acinetobacter oleivorans, and Micrococcus luteus. By inoculating each strain in the piggery liquid manure by 1%, the pH in most strain treatments was maintained at 8.0. Total bacterial counts were maintained at 7.3~7.9 log CFU/ml until 15 days, and then they dropped dramatically down to 5.1~5.5 log CFU/ml. On the 30th day, the treatment group inoculated with Rhodococcus opacus SK2659 showed a relatively high level of ammonium nitrogen removal, which was 39% of that of the control group. When Rhodococcus opacus SK2659 was inoculated, H2S concentration after 100 days was 3.23% compared with the control (no inoculation), suggesting that Rhodococcus opacus SK2659 is an excellent strain for removing malodor gas. The gas production of the treatments was lower than that of the control. The total accumulated amount of gas production in most strain treatments was a quarter of the gas production compared to the control throughout the experimental periods. Acinetobacter oleivorans SK2675 showed the lowest level at 12.39% compared to the control in gas production. In conclusion, the use of mixture strains, such as Rhodococcus opacus SK2659 and Acinetobacter oleivorans SK2675 isolated in this study could increase the efficacy of malodor gas reduction in the biological treatment of piggery manure.

• Applied Biological Chemistry
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• v.10
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• pp.69-100
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• 1968

1. In order to investigate on the microflora and enzyme activity of mold wheat 'Nuruk' , the major source of microorganisms for the brewing of Takju (a Korean Sake), two samples of Nuruk, one prepared at the College of Agriculture, Chung Nam University (S) and the other perchased at a market (T), were taken for the study. The molds, aerobic bacteria, lactic acid bacteria, and yeasts were examined and counted. The yeasts were classified by the treatment with TTC (2, 3, 5 triphenyltetrazolium chloride) agar that yields a varied shade of color. The amylase and protease activities of Nuruk were measured. The results were as the followings. a) In the Nuruk S found were: Aspergillus oryzae group, $204{\times}10^5$; Black Aspergilli, $163{\times}10^5$; Rhizogus, $20{\times}10^5$; Penicillia, $134{\times}10^5$; Areobic bacteria, $9{\times}10^6-2{\times}10^7$; Lactic acid bacteria, $3{\times}10^4$ In the Nuruk T found were: Aspergillus oryzae group, $836{\times}10^5$; Black Aspergilli, $286{\times}10^5$; Rhizopus, $623{\times}10^5$; Penicillia, $264{\times}10^5$; Aerobic bacteria, $5{\times}10^6-9{\times}10^6$; Lactic acid bacteria, $3{\times}10^4$ b) Eighty to ninety percent of the aerobic bacteria in Nuruk S appeared to belong to Bacillus subtilis while about 70% of those in Nuruk T seemed to be spherical bacteria. In both Nuruks about 80% of lactic acid bacteria were observed as spherical ones. c) The population of yeasts in 1g. of Nuruk S was about $6{\times}10^5$, 56.5% of which were TTC pink yeasts, 16% of which were TTC red pink yeasts, 8% of which were TTC red yeasts, 19.5% of which were TTC white yeasts. In Nuruk T(1g) the number of yeasts accounted for $14{\times}10^4$ and constituted of 42% TTC pink. 21% TTC red pink 28% TTC red and 9% TTC white. d) The enzyme activity of 1g Nuruk S was: Liquefying type Amylase, $D^{40}/_{30},=256$ W.V. Saccharifying type Amylase, 43.32 A.U. Acid protease, 181 C.F.U. Alkaline protease, 240C.F.U. The enzyme activity of 1g Nuruk T was: Liquefying type Amylase $D^{40}/_{30},=32$ W.V. Saccharifying type amylase $^{30}34.92$ A.U. Acid protease, 138 C.F.U. Alkaline protease 31 C.F.U. 2. During the fermentation of 'Takju' employing the Nuruks S and T the microflora and enzyme activity throughout the brewing were observed in 12 hour intervals. TTC pink and red yeasts considered to be the major yeasts were isolated and cultured. The strains ($1{\times}10^6/ml$) were added to the mashes S and T in which pH was adjusted to 4.2 and the change of microflora was examined during the fermentation. The results were: a) The molds disappeared from each sample plot since 2 to 3 days after mashing while the population of aerobic bacteria was found to be $10{\times}10^7-35{\times}10^7/ml$ inS plots and $8.2{\times}10^7-12{\times}10^7$ in plots. Among them the coccus propagated substantially until some 30 hours elasped in the S and T plots treated with lactic acid but decreased abruptly thereafter. In the plots of SP. SR. TP. and TR the coccus had not appeared from the beginning while the bacillus showed up and down changes in number and diminished by 1/5-1/10 the original at the end stage. b) The lactic acid bacteria observed in the S plot were about $7.4{\times}10^7$ in number per ml of the mash in 24 hours and increased up to around $2{\times}10^8$ until 3-4 days since. After this period the population decreased rapidly and reached about $4{\times}10^5$ at the end, In the plot T the lactic acid becteria found were about $3{\times}10^8$ at the period of 24 fours, about $3{\times}10$ in 3 days and about $2{\times}10^5$ at the end in number. In the plots SP. SR. TP, and TR the lactic acid bacteria observed were as less as $4{\times}10^5$ at the stage of 24 hours and after this period the organisms either remained unchanged in population or ceased to exist. c) The maiority of lactic acid bacteria found in each mash were spherical and the change in number displayed a tendency in accordance with the amount of lactic acid and alcohol produced in the mash. d) The yeasts had showed a marked propagation since the period of 24 hours when the number was about $2{\times}10^8$ ㎖ mash in the plot S. $4{\times}10^8$ in 48 hours and $5-7{\times}10^8$ in the end period were observed. In the plot T the number was $4{\times}10^8$ in 24 hours and thereafter changed up and down maintaining $2-5{\times}10^8$ in the range. e) Over 90% of the yeasts found in the mashes of S and T plots were TTC pink type while both TTC red pink and TTC red types held range of $2{\times}10-3{\times}10^7$ throughout the entire fermentation. f) The population of TTC pink yeasts in the plot SP was as $5{\times}10^8$ much as that is, twice of that of S plot at the period of 24 hours. The predominance in number continued until the middle and later stages but the order of number became about the same at the end. g) Total number of the yeasts observed in the plot SR showed little difference from that of the plot SP. The TTC red yeasts added appeared considerably in the early stage but days after the change in number was about the same as that of the plot S. In the plot TR the population of TTC red yeasts was predominant over the T plot in the early stage which there was no difference between two plots there after. For this reason even in the plot w hers TTC red yeasts were added TTC pink yeasts were predominant. TTC red yeasts observed in the present experiment showed continuing growth until the later stage but the rate was low. h) In the plot TP TTC pink yeasts were found to be about $5{\times}10^8$ in number at the period of 2 days and inclined to decrease thereafter. Compared with the plot T the number of TTC pink yeasts in the plot TP was predominant until the middle stage but became at the later stage. i) The productivity of alcohol in the mash was measured. The plot where TTC pink yeasts were added showed somewhat better yield in the earely stage but at and after the middle stage the difference between the yeast-added and the intact mashes was not recognizable. And the production of alcohol was not proportional to the total number of yeasts present. j) Activity of the liquefying amylase was the highest until 12 hours after mashing, somewhat lowered once after that, and again increased around 36-48 hours after mashing. Then the activity had decreased continuously. Activity of saccharifying amylase also decreased at the period of 24 hours and then increased until 48 hours when it reached the maximum. Since, the activity had gradually decreased until 72 hours and rapidly so did thereafter. k) Activity of alkaline protease during the fermentation of mash showed a tendency to decrease continusously although somewhat irregular. Activity of acid protease increased until hours at the maximum, then decreased rapidly, and again increased, the vigor of acid protease showed better shape than that of alkaline protease throughout. 3. TTC pink yeasts that were predominant in number, two strains of TTC red pink yeasts that appeared throughout the brewing, and TTC red yeasts were identified and the physiological characters examined. The results were as described below. a) TTC pinkyeasts (B-50P) and two strains of TTC red pink yeasts (B-54 RP & B-60 RP) w ere identified as the type of Saccharomyces cerevisiae and TTC pink red yeasts CB-53 R) were as the type of Hansenula subpelliculosa. b) The fermentability of four strains above mentioned were measured as follows. Two strains of TTC red pink yeasts were the highest, TTC pink yeasts were the lowest in the fermantability. The former three strains were active in the early stage of fermentation and found to be suitable for manufacturing 'Takju' TTC red yeasts were found to play an important role in Takju brewing due to its strong ability to produce esters although its fermentability was low. c) The tolerance against nitrous acid of strains of yeast was marked. That against lactic acid was only 3% in Koji extract, and TTC red yeasts showed somewhat stronger resistance. The tolerance against alcohol of TTC pink and red pink yeasts in the Hayduck solution was 7% while that in the malt extract was 13%. However, that of TTC red yeasts was much weaker than others. Liguefying activity of gelatin by those four strains of yeast was not recognized even in 40 days. 4. Fermentability during Takju brewing was shown in the first two days as much as 70-80% of total fermentation and around 90% of fermentation proceeded in 3-4 days. The main fermentation appeared to be completed during :his period. Productivity of alcohol during Takju brewing was found to be apporximately 65% of the total amount of starch put in mashing. 5. The reason that Saccharomyces coreanuss found be Saito in the mash of Takju was not detected in the present experiment is considered due to the facts that Aspergillus oryzae has been inoculated in the mold wheat (Nuruk) since around 1930 and also that Koji has been used in Takju brewing, consequently causing they complete change in microflora in the Takju brewing. This consideration will be supported by the fact that the original flavor and taste have now been remarkably changed.

• Journal of Sericultural and Entomological Science
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• v.15 no.2
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• pp.21-28
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• 1973

This report is prepared to promote cocoon natures for the use of silk reeling material. It is easily understandable that there must be disuniformity composed with superior group and inferior group in commercial silkworms. If such different groups be seperated by some method, it would be a great contribution for the cocoon production. For a comparative purpose, silkworm sex seperation carried out because male silkworms produce more silk than female worms. The author has developed a new chemical reagent available for the seperation of superior group and inferior group from commercial silkworms, which he has named it as Better Hybrid Controller (BHC). The obtained comparative results are summarized as followings. 1. Basic investigation of BHC application a) In case BHC applied with hybrid worms and pure line, the former one starts to adapt mulberry leaves earlyer than pure line variety. b) The mulberry adapting interval distribution of pure line worms after BHC application showed U type distribution, but hybrid worms showed L type or Poisson's distribution. c) In case of BHC application with silkworms, the longer period application is, the duller distribution was formed. d) When silkworms are seperated in two groups by use of BHC application, the earlyer mulberry adapted group is seemed as stronger than the other part and the group ratio is 2 : 1. 2. Comparation between sex seperation result and better hydrid control (BHC) seperation result. a) The cocoon shell per cent of male worm group showed betweer result than the female group but only 0.4% difference between sexes. b) The cocoon shell per cent of superior group, seperated by BHC, showed 0.7% more than the inferior group. c) The average cocoon shell per cent of BHC treated cocoons showed much more than the Control group as 1.6∼2.4% increase. Enven the inferior group showed better result than the Control. d) Such unexpected result is considered to be the result that BHC application is activating some thing with silkworm physiology. e) On the ether hand, the result of sexes seperated groups or male worm group did not show desirable conclusion as far as cocoon shell per cent is concerned. f) However, when the male group was reeled as silk, it showed much better silk yield or silk per cent of cocoon than the female group as much as one per cent difference between by sexes. Such result was brought by superior silk yield from cocoon shell as much as 87.4%. g) On the other hand, the male group showed lowest non breaking reelable ratio (63%) among all group comparation. h) When we compare cocoon qualities by sex seperation and BHC seperation against the Control, there is no qualitative change, but BHC group showed quantitative promotion with cocoon bave length as much as about hundred meters. i) In case of calculation for productive income of cocoon production, BHC applied group showed about ten per cent income promotion more than the Control. The sexes seperated group, however, showed rather negative result because the male cocoon produced poor weight per box eggs which could not cover it by the inclose of silk yield of it. j) So, the BHC application with the fetched worm stage brought about big promotion for cocoon production. k) BHC method may be used either for seperation purpose or quantitative promotion with whole silk-worms. 3. Only male silkworms rearing did not show desirable productivity, so there is no reason to work out it in the fetching stage of worm.