• Journal of Microbiology and Biotechnology
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• v.29 no.4
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• pp.527-537
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• 2019

Three types of meongge (Halocynthia roretzi) jeotgal (MJ) were prepared with 3 different types of salts (12%, w/v): purified salt (PS), solar salt aged for 3 years (SS), and bamboo salt that had been recrystalized 3 times (BS). One set of MJ was fermented with starters, Bacillus subtilis JS2 and Tetragenococcus halophilus BS1-37 (each 6 log CFU/g), and another set without starters for 42 days at $10^{\circ}C$. The LAB count of the SSMJ (non-starter) was highest at day 28 (2.30 log CFU/g). The pH of the PSMJ and SSMJ was 5.72-5.77 at day 0, and 5.40-5.50 at day 42. BSMJ showed higher pH and lower titratable acidities than other samples. Amino-type nitrogen (ANN) increased continuously, and SSMJ showed higher values than other samples from day 14. Bacterial species of non-starter MJ were examined by culture independent method. Clone libraries of 16S rRNA genes were constructed in Escherichia coli from total DNA from non-starter MJ samples at day 0, 14, and 28. Thirty clones per each sample were randomly selected and DNA sequences were analyzed. Variovorax sp., uncultured bacterium, and Acidovorax sp. were the most dominant group at day 0, 14, and 28, respectively. Lactobacillus sakei and Streptococcus sp. were the next dominant group in SSMJ at day 28. A Streptococcus sp. was detected from PSMJ at day 28. Sensory evaluation for MJ samples at day 28 showed that SSMJ got higher overall acceptability scores. These results showed that solar salt can cause desirable changes in the microbial community of fermented foods, thereby positively affecting their overall quality.

• Korean Journal of Veterinary Service
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• v.22 no.2
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• pp.121-128
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• 1999

The present study was conducted to investigate the incidence of pneumonic lesions with special regard to enzootic pneumonia and the microbiology of pneumoic lungs from 544 slaughter pigs during the period from October 1995 to September 1996. The incidence of enzootic pneumonic lesion was 76.3% (41s/s44) and pleurisy was detected from 7.9% of slaughter pigs. Seasonal prevalence of pneumonic lesions in slaughter pigs were in order of prevalence of 82.9% in spring, 76.8% in winter, 74.8% in autumn and 69.0% in summer, respectively. Pasteurella multocida, Streptococcus sp, Str suis, Corynebacterium sp, Actinobacillus pleuropneumoniae, Hemophilus parasuis, and Klebsiella pneumoniae were detected in order of prevalence from 16.9%, 15.9%, 7.5%, 6.0%, 1.4%, 1.0% and 0.5% of 415 pneumonic lungs, respectively. P multocida were susceptible to oxytetracycline, polymyxin-B, streptomycin, and vancomycin, while the majority of them were resistant to amoxicillin, ampicillin, cephalothin, kanamycin, and penicillin-G. Str suis were susceptible to amoxicillin, ampicillin, cephalothin, penicillin-G, although the majority of them were resistant to erythromycin, oxytetracycline, streptomycin, vancomycin. A pleuropneumoniae were susceptible to ampicillin, and cephalothin, but the majority of them were resistant to oxytetracycline.

• Journal of fish pathology
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• v.21 no.1
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• pp.29-34
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• 2008

In this study, we examined in vitro antimicrobial activity of the hydrolysis compound (MBT-01108) of cactus stem (Opuntia ficus-indica var. saboten Makino) against 18 strains of fish pathogenic bacteria, Edwardsiella tarda, Listonella anguillarum, Vibrio sp., Lactococcus garvieae, L. raffinose, Streptococcus parauberis and S. iniae. Antibiotic susceptibility of the same bacteria was also assayed to commercial discs containing various antibacterials. According to these results, MBT-01108 showed the excellent antimicrobial activity against the tested pathogenic bacteria.

• Journal of fish pathology
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• v.13 no.1
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• pp.1-6
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• 2000

The antibacterial activity of marine bacterium(Pseudomonas aeruginosa JYMB1-3) was assayed against Vibrio anguillarum with the aim of evaluating the possible use for biocontrolling fish disease as probiotic strain. Inhibition test on the solid medium showed that vibrios were especially sensitive to the JYMB1-3. Edwardsiella tarda, Streptococcus sp. and Staphylococcus epidermidis were also sensitive to that strain, however the antibacterial abilities were varied to the pathogens. The vibriostatic activity of antibacterial substance produced from $10^7$ cells of the strain for 24 hours was equivalent to $2.5{\mu}g$ of chloramphenicol.

• Journal of fish pathology
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• v.23 no.1
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• pp.27-35
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• 2010

Pathogens on the cultured 579 rockfish, Sebastes schlegeli in the marine cage farms from Geoje and Tongyeong of the Southern sea were investigated from 2006 to 2008. The pathogens were detected throughout the year at 46.0~90.0% for 3 years and the detection rate was low with an average 58.1% in May and high with an average 81.5% in October. Bacteria only, bacteria-parasite mix and virus only were found in October and November as well as parasite only, whereas infection of parasite only was dominant in May when the temperature increased and in August when the temperature peaked. Of rockfish, Microcotyle sp. and Caligus sp. were dominant for parasitic disease, and Vibrio sp. and Streptococcus sp. were dominant bacteria. For virus, RSIV and VNNV were detected as dominant organisms. While no virus was detected in 2006, VNNV, VHSV and RSIV were detected in 2007 due to $1.5\sim2.0^{\circ}C$ higher temperature than 2006 in the summer season. For total prevalence by rockfish sizes, the highest was found at 50.0~87.1% in 11~15cm sizes and 50% was found in 30 cm size. Parasite showed a similar trend of 50.0~79.6% as the total prevalence. Prevalence for bacteria varied from 1.6% (for 10 cm group) to 23.8% (for 26 cm group) and higher virus prevalence of 21.5% was found from below 25 cm group.

• Fisheries and Aquatic Sciences
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• v.6 no.1
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• pp.27-33
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• 2003

A lactic acid bacterium showing antimicrobial activity against fish pathogen was isolated from gastrointestinal tract of flounder for the purpose of use as an aquaculture probiotics. From the analysis of morphological and physiological characteristics, the isolated strain was named as Lactococcus sp. HM58. Antimicrobial substance (AMS) from Lactococcus sp. HM58 showed strong growth inhibitory activity against Streptococcus sp., which is a fish pathogenic bacterium. AMS was presumed a proteinaceous compound with stability in heat and wide pH range from 2 to 10. It was started to produce in exponential growth phase and was not produced any more in stationary phase. It showed comparatively broad antimicrobial spectrum against most of gram positive bacteria used for this study. About $84\%$ of Lactococcus sp. HM58 was able to survive in the artificial gastric juice though it was low to the extent in the artificial bile juice. In the sensitivity test for various antibiotics, this strain was highly sensitive for doxycycline, erythromycin, amoxicillin clavu1anic acid and ampicillin.

• Korean Journal of Microbiology
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• v.27 no.4
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• pp.404-414
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• 1989

Attempts were made to isolate and identify Gram-positive or lactic acid bacteria in Kimchi fermentation. Species diversity depended on isolation media and temperatures, and diversity tended to be reduced with decrease of temperature. MRS and KM (natural medium prepared from Kimchi materials) were suitable respectively for isolation and present number of species. Identification of isolates was performed by dichotomous identification schemes arranged on the basis of Bergey's manual of Systematic Bacteriology (1986). Gram-positive bacteria isolated at different temperatures (5, 15, $25^{\circ}C$) were 5 species of Leuconostoc, 4 species of Streptococcus, 3 species of Pediococcus, 2 species of Bacillus and 18 species of Lactobacillus. Species with high frequency of appearance were Lactobacillus plantarum, Streptococcus raffinolactis, Leuconostoc mesenteroides subsp. mesenteroides at $25^{\circ}C$, L. plantarum, Lactobacillus fructosus, L. mesenteroides subsp. mesenteroides at $15^{\circ}C$ and L. mesenteroides subsp. mesenteroides, Leuconosotoc paramesenteroides, Lactobacillus maltaromicus at $15^{\circ}C$. In general, Kimchi fermentation was achieved by Lactobacillus spp. (59.7% frequency) at $25^{\circ}C$ and Leuconostoc spp. (65.2% frequency) at $5^{\circ}C$. Pediococcus cerevisiae and Streptococcus faecalis which have been so far known as bacteria of Kimchi fermentation were not isolated.

• The Korean Journal of Food And Nutrition
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• v.12 no.1
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• pp.7-12
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• 1999

Bovine mastitis was examined by use of the rolling ball viscosity test in Kwang-ju area. Antibiotic sus-ceptibility of isolated pathogens from raw milk was investigated by the disc method. Positive rate of so-matic cell counts (over 500,000 cells/ml) was decreased from 11.1% in 1991∼1993 to 8.0-% in 1995∼1997. Isolated mastitis-causing-pathogens were identified as Staphylococcus sp. (49.7%) Escherichia coki(23.2%) Streptococcus sp. (10.4%) and Bacillus sp(7.2%) Antibiotic susceptibility of isolated pathogens to almost antibiotics was decreased.

• Food Science and Preservation
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• v.6 no.4
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• pp.442-447
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• 1999

A curd yogurt was prepared by fermenting milk added with skim milk powder and purple sweet potato by culture of 5 types of lactic acid bacteria(Lactobacillus delbruekii sub. sp. lactis, Streptococcus lactis, acidity, number of viable cell, stability of purple sweet potato's pigment and keeping qualify. Among the organisms tested, the acid production and number of viable cell by the culture of L bulgaricus remarkably increased for the first 12 hem which showed 1.04${\times}$10$\^$9/ CFU/mL in number of viable cell and 4.22 In pH where as fermentation by the culture of B. bifidum was slow. After 36 hours of incubation which showed 3.3 ${\times}$ l0$\^$8/ CFU/mL in number of viable cell and 5.1 in pH. In stabilities of purple sweet potato anthocyanin pigment n fermentation, yogurt by B. bifidum was found to be most stable followed by Leuc. lactis, L. delbruekii sub. sp. lactis, L bulgaricus, but yogurt by St. lactis was not stable. When curd yogurt added with Purple sweet Potato was kept at 2∼3$^{\circ}C$ for 14 day, its keeping quality(pH, titratable acidity, number of viable cell) was relative good except product by L. bulgaricus was found to be decreased most of viable cell. After 2 weeks of keeping, pigment of yogurt was decreased by B. bifidum, stable by L. delbruekii sub. sp. lactis.

• Korean Journal of Food Science and Technology
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• v.51 no.2
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• pp.114-119
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• 2019

Seven antimicrobial agents known to be effective in inhibiting the growth of lactic acid bacteria were applied to ensure the microbial safety of low-salted squid and myungran jeotgal with 4-6% salinity. These agents reduced the salt content by 50% compared with the conventional Jeotgal. Lactic acid bacteria such as Lactobacillus sp., Streptococcus sp., and Pediococcus sp. were commonly found to account for 80% of microbial organisms, and yeast and fungi were observed in squid and myungran jeotgal, respectively. The total bacterial counts in squid and myungran jeotgal showed 94.20 and 90.87% reduction after the addition of 0.5% (w/w) glycine. The microbial counts in squid and myungran jeotgal decreased $10^1-10^2CFU/g$ when compared with the control after 21 days at $10^{\circ}C$. Glycine was found to be an effective commercial antimicrobial agent that can be used to control bacterial count in low-salted Jeotgal without affecting sensory qualities such as overall taste and flavor.