• Title/Summary/Keyword: total viable cell

Search Result 296, Processing Time 0.028 seconds

Changes in Physicochemical Properties and Microorganisms during the Storage of Kimchi Stew저s Sauce (김치찌개용 양념의 저장 및 품질특성의 변화)

  • 권혜순
    • Journal of the Korean Society of Food Science and Nutrition
    • /
    • v.28 no.1
    • /
    • pp.107-112
    • /
    • 1999
  • Physicochemical properties and microflora of kimchi stew's sauce were investigated during 6 months at 13oC, 27oC and 37oC to study the changes of its quality. The final pH values in the sauce showed a slight decrease to 4.46, 4.38 and 4.21 during storage at 13oC, 27oC and 37oC, respectively. Color(L, a, b values), salinity, moisture and Aw in the sauce were decreased during storage. However, the values of brix and browning, and the amounts of total sugar, crude protein and crude fat in the sauce were increased during storage. All the reactions occurred more rapidly in the samples stored at 37oC than those stored at 27oC and 13oC. The viable cell counts of aerobic bacteria in the sauce were changed remarkably during storage, but viable cell counts of lactic acid bacteria were decreased. Yeast, mold and E. coli were not found in the above temperatures during storage. Regression analysis between sensory scores and quality characteristics showed that the ΔE value was a major quality index for the deterioration of kimchi stew's sauce. The shelf lives of sauces at 13oC, 27oC, 37oC were estimated to be 24 months, 6 months and 6 months, respectively.

  • PDF

Induction and resuscitation of viable but nonculturable Edwardsiella tarda (Edwardsiella tarda의 비배양성 생존상태(VBNC) 유도 및 소생 특성)

  • Kang, Nam I;Kim, Eunheui
    • Korean Journal of Microbiology
    • /
    • v.52 no.3
    • /
    • pp.313-318
    • /
    • 2016
  • Bacteria in the viable but nonculturable (VBNC) state fail to produce colonies on routine bacteriological media, but are still alive in the state of very low metabolic activity. The aim of the present study was to induce the VBNC state of the Edwardsiella tarda using sea water microcosm under starvation conditions at $10^{\circ}C$ and to investigate resuscitation of the VBNC cells in temperatures changed from 10 to $25^{\circ}C$, with and without additives. E. tarda entered into the VBNC state within about 42-84 days of incubation in the microcosm. Throughout this period, the total cell counts as determined using acridine orange direct counting remained near the original inoculum level of ${\sim}10^8cells/ml$. The live cell counts measured with direct viable counting, on the other hands, declined to ${\sim}10^4cells/ml$. When the VBNC cells were incubated with addition of yeast extract, fish muscle extract or serum at $25^{\circ}C$, the ratios of resuscitated samples were 37%, 23%, and 37%, respectively. The characteristics of resuscitated E. tarda were consistent with those of the original E. tarda. When the resuscitated E. tarda were intraperitoneally injected into olive flounders, all fishes died within 5 days, indicating that the VBNC E. tarda might retain its pathogenic potential. Therefore, E. tarda under starvation conditions in the winter enter into the VBNC state and the VBNC E. tarda cells resuscitated at summer and autumn seawater temperature are considered to be pathogen continuously to olive flounder on the southern coast of Korea.

Changes in Fermentation Characteristics of Kimchi Added with Leek (부추첨가 김치의 발효특성 변화)

  • 이귀주;김유경
    • Journal of the Korean Society of Food Science and Nutrition
    • /
    • v.28 no.4
    • /
    • pp.780-785
    • /
    • 1999
  • The effect of addition in different amounts of leek(4, 8, 12% respectively) during fermentation of kimchi was investigated. Fermentation characteristics such as pH, acidity and total reducing sugars as well as microbiological properties were determined. During fermentation, pH was more slowly lowered in kimchi added with leek than in control and titrable acidity of these kimchi was lower than that of control. Viable cells of total bacteria and lactic acid bacteria in these kimchi were higher than that of control during fermentation. Content of total reducing sugars was higher than that of control. Three kinds of reducing sugars such as fructose, glucose and galactose were detected and the dominant one appeared to be fructose. These results suggested that addition of leek seems to retard fermentation of kimchi due to their anti microbial actvity.

  • PDF

Studies on Ginseng Vinegar (인삼식초에 관한연구)

  • 김승겸
    • The Korean Journal of Food And Nutrition
    • /
    • v.12 no.5
    • /
    • pp.447-454
    • /
    • 1999
  • Ginseng-vinegars were produced by the fermentation of 5% ethanol solution contained ginseng, red ginseng, ginseng marc and red ginseng marc using Acetobacter aceti 3281 for 26 days at 35$^{\circ}C$. The ginseng and red ginseng vinegar contained 0.236mg/ml of total sugar 0.236mg/ml of reducing sugar and 0.05% of ethanol and 1.005 of specific gravity 8,58CFU of viable cell count 3,24 of pH and 5.11% of acidity. Whereas the vinegars produced using the water-extracted red ginseng marc and the ethanol-extracted red ginseng marc were consisted of total sugar was 1.27mg/ml and 1.60mg/ml reducing sugar was 0.077mg/ml and 0.725mg/ml specific gravity was 1.001 and 1.004 the number of viable cells was 8.51CFU/ml and 8.1CFU/ml pH was 2.81 and 2.89 acidity was 5.18% and 5.32% respectvely ethanol concentration was 0.05% in both cases. In five-grade scoring test of sensory evaluation, it was estimated favorable that each vinegar made by were-extracted red ginseng marc, ethanol-extracted red ginseng marc ginseng and red ginseng ginseng from 0.5 to 32% of water-and ethanol-extract red ginseng was extracted with 10% white vinegar for 30 days. The best sensory vinegars were obtained that ginseng of 0.4~1.6% above red glnsend of 0.8% water-extracted red ginseng marc of 0.8~1.6% and ethanol-extracted red ginseng marc of 0.4~1.6% added in 10% white vinegar respectively.

  • PDF

Characterization and Identification of Lactic Acid Bacteria Isolated from Fermented Milks in Iran (이란 발효 유제품에서 분리한 유산균의 특성)

  • Hyoju Park;Dong-June Park;Sejong Oh
    • Journal of Dairy Science and Biotechnology
    • /
    • v.41 no.4
    • /
    • pp.211-218
    • /
    • 2023
  • This study aimed to identify lactic acid bacteria isolated from eight fermented milk products in Iran. We enumerated Lactobacillus species using De Man-Rogosa-Sharpe (MRS)-maltose and MRS agar with pH adjusted to 5.2, as well as assessment at 37℃ for 48 hr, studied Streptococcus spp. using M17 agar at 43℃ for 24 hr, and assessed Bifidobacterium species using nalidixic acid, paromomycin sulfate, neomycin sulfate, and lithium chloride (BL-NPNL) agar at 37℃ for 48 hr. The total viable Streptococcus spp. cell in fermented milk varied at 4.73-8.83 log CFU/mL. However, Bifidobacterium spp. were not detected in any of the tested samples. Lactobacilli were not detected in four of the eight samples, and viable Lactobacilli cells in the remaining four samples ranged 2.48-3.85 log CFU/mL. The pH of the tested samples ranged 3.53-4.19, and soluble solids (Brix measurement) ranged 7.5%-17.9%. A total of 130 isolates of gram-positive catalase-positive bacteria were characterized at the species level using 16S rRNA sequencing. Sequence analysis identified six species: Streptococcus thermophilus, Lactobacillus delbrueckii subsp. sunkii, Lactobacillus delbrueckii subsp. indicus, Lactiplantibacillus plantarum, Lacticaseibacillus rhamnosus, and Levilactobacillus brevis.

Effects of Knockout Serum Replacement in the Culture Medium on the Proliferation of Porcine Fetal Fibroblasts In Vitro

  • Kim, Eun-Ju;Park, Jung-Joo;Choi, Young-Ju;Park, Sang Kyu;Roh, Sang-Ho
    • International Journal of Oral Biology
    • /
    • v.35 no.1
    • /
    • pp.1-5
    • /
    • 2010
  • Human fibroblasts that maintain the structural integrity of connective tissues by secreting precursors of the extracellular matrix are typically cultured with serum. However, there are potential disadvantages of the use of serum including unnatural interactions between the cells and the potential for exposure to animal pathogens. To prevent the possible influence of serum on fibroblast cultures, we devised a serum-free growth method and present in vitro data that demonstrate its suitability for growing porcine fetal fibroblasts. These cells were grown under four different culture conditions: no serum (negative control), 10% fetal bovine serum (FBS, positive control), 10% knockout serum replacement (KSR) and 20% KSR in the medium. The proliferation rates and viabilities of the cells were investigated by counting the number of cells and trypan blue staining, respectively. The 10% FBS group showed the largest increase in the total number of cells ($1.09\;{\times}\;10^5\;cells/ml$). In terms of the rate of viable cells, the results from the KSR supplementation groups (20% KSR:64.7%; 10% KSR: 80.6%) were similar to those from the 10% FBS group (68.5%). Moreover, supplementation with either 10% ($3.0\;{\times}\;10^4\;cells/ml$) or 20% KSR ($4.8\;{\times}\;10^4\;cells/ml$) produced similar cell growth rates. In conclusion, although KSR supplementation produces a lower cell proliferation rate than FBS, this growth condition is more effective for obtaining an appropriate number of viable porcine fetal fibroblasts in culture. Using KSR in fibroblast culture medium is thus a viable alternative to FBS.

Inhibitory Effects of Latilactobacillus curvatus BYB3 Cell-Free Extract on Human Melanoma B16F10 Cells and Tumorigenic Mice

  • Dingyun Li;Xing Wang;Dong-June Park;Dong Hun Lee;Sejong Oh
    • Journal of Microbiology and Biotechnology
    • /
    • v.34 no.3
    • /
    • pp.589-595
    • /
    • 2024
  • Latilactobacillus curvatus BYB3 (BYB3) is a species of lactic acid bacteria, formerly named Lactobacillus curvatus, which is isolated from kimchi. In this study, the effect of BYB3, Lactobacillus rhamnosus GG, and Lactobacillus acidophilus GP1B strain extracts at various concentrations was examined on B16F10, a mouse melanoma cell line. Cell viability was examined via MTT assay, and the results indicated that compared to the other two probiotics, BYB3 significantly decreased the total percentages of viable cells. The effects of BYB3 on cell migration and proliferation in B16F10 cells were evaluated using wound healing mobility and proliferation assays, respectively; the results indicated that BYB3 inhibits cell migration and proliferation in a concentration-dependent manner. Using human dermal fibroblast cells to investigate BYB3 extract in vivo had no effect on skin-related cells. Nonetheless, the BYB3 extract inhibited tumor growth in a mouse model, as demonstrated by liver slices. Therefore, this suggests that using BYB3 extract to inhibit melanoma may be a novel approach.

Effect of Low-Dose Radiation on Quality Characteristics of Takju (저선량 방사선 처리가 탁주 품질특성에 미치는 영향)

  • Lee, Yun-Gyu;Tak, Eun-Mi;Kim, Bo-Mi-Na;Seo, Choung-Won;Choi, Seung-Hwan;Shin, Yong-Seob;Kim, Seon-Chil
    • Korean Journal of Digital Imaging in Medicine
    • /
    • v.13 no.3
    • /
    • pp.133-137
    • /
    • 2011
  • This research investigated how low dose radiation affected the quality characteristics of Takju. The treatment group were the quality characteristics of control group, Takju treated by radiation of separate 4, 7, 10 Gy and sterilized Takju. We measured pH, titratable acidity, alcohol, brix, total viable cell count, Hunter's color values, sensory characteristic. As a result, We discovered there were minute changes in pH, titratable acidity, alcohol, brix, total viable cell count. Likewise, The color appeared changes on separate radiation dose. In the sensory characteristic, People's preference ranked better than average level according to priority Takju treated by 4, 7, 10 radiation. In conclusion, Low dose radiation had little effect on the quality characteristics of Takju. However, Takju received a favorable review by some people In test of taste such as after taste. So We thought, such as preservation, the research using the radiation should be continually conducted.

  • PDF

Microbial Contamination by Bacillus cereus, Clostridium perfringens, and Enterobacter sakazakii in Sunsik

  • Lee, Eun-Jin;Kim, Sung-Gi;Yoo, Sang-Ryeol;Oh, Sang-Suk;Hwan, In-Gyun;Kwon, Gi-Sung;Park, Jong-Hyun
    • Food Science and Biotechnology
    • /
    • v.16 no.6
    • /
    • pp.948-953
    • /
    • 2007
  • The powdered cereal sunsik is a partially thermal-processed product that required safety evaluations for food-borne pathogens. Thirty-six sunsik products from Korean markets were collected and analyzed for contamination by total viable cell counts, coliforms, Escherichia coli, and the spore-forming Clostridium perfringens and Bacillus cereus. Enterobacter sakazakii, as a newly emerging pathogen, was also analyzed. Approximately 28% of sunsik were contaminated at 5 log CFU/g for total viable counts. Coliforms and E. coli were detected in 33 and 4% of the samples, respectively. The spore-forming B. cereus was found in 42% of the samples at a maximal level of 3 log CFU/g on average. About 6% the samples were contaminated with Cl. perfringens at an average level of 15 CFU/g. Forty-five % of sunsik contained E. sakazakii, at levels from 0.007 to over 1.1 cell/g by MPN method. In addition, one sunsik product for infants and children showed over 3 log CFU/g for both B. cereus and E. sakazaki. Therefore, concern should be placed on controlling for microbial hazards such as B. cereus and E. sakazakii in sunsik, particularly for the products fed to infants under 6 months of age.

Effects on the Shelf-life of Tofu with Ethanol Extracts of Rubus coreanus miquel, Therminalia chebula Retz and Rhus javanica (두부의 저장성에 미치는 복분자, 가자육, 오배자 에탄올 추출물의 효과)

  • Oh, Se-Wook;Lee, Young-Chul;Hong, Hee-Do
    • Korean Journal of Food Science and Technology
    • /
    • v.34 no.4
    • /
    • pp.746-749
    • /
    • 2002
  • From 7 different medicinal herbs, Rubus coreanus miquel, Therminalia chebula Retz and Rhus javanica was selected by paper disk method against 10 different microorganisms. The ethanol extracts of selected herbs was added into Tofu, and the total viable cell counts was determined. After 4 days, total viable cell count reached to $10^7$ and the Tofu putrefacted. The tested sample added with 0.01% of Terminalia Chebula Retz extract, the shelf-life was extended as 108.8%, with 0.05% was 117.3% and with 0.1% was 132.6%. Among 3 kinds of medicinal herb, Therminalia chebula Retz has better powerful activity than others.