• The Korean Journal of Food And Nutrition
• /
• v.26 no.3
• /
• pp.428-437
• /
• 2013

The physical properties of jellified soybean curd residue (Biji) with the addition of various gums were investigated to optimize the direct availability of a by-product of the tofu production process. The lightness (L value) of the jellified Biji prepared with various gums was approximately 77~80, regardless of the concentration of gum used. Especially at the concentration of 0.1% and 0.3%, a pectin showed a significantly higher value compared with other gelling agents (carrageenan and agar). The strength of samples prepared on the basis of carrageenan showed the value of 335~569 $g/cm^2$ and 234~335 $g/cm^2$ according to the addition of locust bean gum and xanthan gum, respectively. On the other hand, the samples made with pectin and agar were 134~272 $g/cm^2$ and 50~215 $g/cm^2$, respectively. Where locust bean gum was used as a viscous agent, the adhesiveness of sample prepared by adding carrageenan was greater than those made with pectin or agar. The values were -6.0~-11.0 g, -2.7~-10.2 g and -3.7~-7.0 g, respectively. Overall, the strength and adhesiveness of samples according to increase of the added amount of Biji showed constantly increasing trend regardless of the type of gelling agent used. In the sample containing carrageenan this trend was most noticeable.

• Food Science and Biotechnology
• /
• v.18 no.2
• /
• pp.506-512
• /
• 2009

The antimicrobial activity of water and ethanol extracts from 30 species of algae was measured using the agar diffusion method and minimum inhibitory concentration (MIC) test. In agar diffusion method, the 95% ethanol extracts from 12 of the algae showed growth inhibition against the tested microorganisms. In particular, Ishige okamurai, Ecklonia stolonifera, Sargassum siliquastrum, Sargassum thunbergii, Colpomenia bullosa, and Ecklonia cava had strong antibacterial activities against Gram-positive bacteria at 4 mg/mL. In the results of the MIC test, S. siliquastrum showed the most antimicrobial activity, where its MIC values ranged from 0.005 to 0.0075% against Listeria monocytogenes, Clostridium perfringens, and Basillus subtilis. In the thermal stability test, for the ethanol extracts of I. okamurai, E. cava, S. siliquastrum, S. thunbergii, and C. bullosa, the extracts proved to maintain high antimicrobial activities when they were treated at $121^{\circ}C$ for 15 min. In the pH stability test, the antimicrobial activity of the S. siliquastrum ethanol extract was stable from pH 2 to 10, whereas the activity of the other species ethanol extracts were weakened under pH 10 against several microbes.

• Korean Journal of Veterinary Research
• /
• v.37 no.2
• /
• pp.359-365
• /
• 1997

Staphylococcus hyicus subsp. hyicus strains isolated from pigs, chickens and cattle were examined for the production of staphylokinase after inhibition of staphylococcal proteases by two procedures with EDTA(disodium). In one, EDTA was added to the bovine fibrin-dog plasminogen agar medium in concentration of 0.07% and paper strips soaked in 2mg/ml soy bean trypsin inhibitor were then applied on the agar plates. In the other, paper strips soaked in 5% EDTA solution were applied on the bovine fibrin-dog plasminogen agar plates and the strains to be tested were then streaked at right angles with the strip. By these procedures, staphylokinase activity was detected in 8(88.9%) of 9 strains from diseased pigs and in 57(80.3%) of 71 strains from skin of healthy pigs, but not in any strains from skin of healthy chickens and milk samples of mastitic cattle. Additionally kinase activity in 9 Staphylococcus species and subspecies isolated from bovine intramammary infections was also tested by these procedures. Staphylokinase activity was detected in 74.2% of Staph aureus strains and in 25% of Staph xylosus strains.

• Journal of Microbiology and Biotechnology
• /
• v.9 no.4
• /
• pp.482-487
• /
• 1999

The Pseudomonas sp. strain NGK1 (NCIM 5120) was immobilized in calcium alginate, agar, and polyacrylamide gel matrices. The salicylic acid-producing capacity of freely suspended cells was compared with immobilized cells in batches with a shake culture and continuous culture system in a packed bed reactor. Freely suspended cells ($4\times10^{10}cfu/ml$) produced 12 mM of salicylic acid, whereas cells immobilized in calcium alginate ($1.8\times10^{11}$cfu/g beads), agar ($1.8\times10^{11}$cfu/g beads), and polyacrylamide ($1.6\times10^{11}$cfu/g beads) produced 15, 11, and 16mM of salicylic acid, respectively, from naphthalene at an initial concentration of 25 mM. The continuous production of salicylic acid from naphthalene was investigated in a continuous packed bed reactor with two different cell populations. The longevity of the salicylic acid-producing activity of the immobilized cells from naphthalene was also studied in semi continuous fermentations. The immobilized cells could be reused 18, 13, and more than 20 times without losing salicylic acid-producing activity in calcium alginate-,agar-, and polyacrylamide-entrapped cells, respectively. The study reveals a more efficient utilization of naphthalene and salicylic acid production by the immobilized Pseudomonas sp. strain NGK1 as compared to the free cells.

• 한국가시화정보학회:학술대회논문집
• /
• 2007.11a
• /
• pp.88-91
• /
• 2007

Animal cells show different behaviors in response to the mechanical properties of the substrates. We hypothesize that the rigidity of the substrates also affects the bacterial motility and controls the colony dynamics. It is found that the colony size of Escherichia colis and Bacillus subtilis grown on the agar plates is correlated with agarose gel concentrations and thus with the substrate rigidity. High- resolution microscopic imaging reveals that bacteria in single colonies form different aggregation patterns on the agar plates with varying gel concentration. We measured the apparent diffusion coefficients in the agarose gel plates made with different gel concentrations. Mathematical modeling and quantitative imaging of dye dispersion in the agar plates suggest that there is a close connection between the diffusion rate and the colony size. Nanoscale pore structures and kinetic constraints in the porous media may have an effect on bacterial colony dynamics.

• Food Science and Biotechnology
• /
• v.15 no.6
• /
• pp.866-870
• /
• 2006

The maintenance of physiological activity during dilution is very critical for the accurate enumeration of Vibrio spp. in marine samples. We investigated the effect of various diluents on the recovery of Vibrio parahaemolyticus using the direct plate counting and most probable number (MPN) methods. The effects of NaCl (0.85 and 3%) and pH (from 6.6 to 7.4) in diluents based on distilled water or phosphate buffered saline (PBS) were evaluated with three V. parahaemolyticus strains. PBS-3% NaCl (pH 6.6), as opposed to PBS, was the most effective diluent at maintaining viable cell numbers up to 2 log CFU/g during dilution for direct plate counting using on thiosulfate citrate bile salts sucrose (TCBS) selective agar, as well as minimizing the difference in cell numbers between TCBS and non-selective nutrient agar. It also increased counts of V parahaemolyticus inoculated into oysters relative to PBS (p<0.01), suggesting that PBS-3% NaCl (PH 6.6) can reduce the problem of underestimating V. parhaemolyticus counts using PBS alone.

• Journal of the Korean Society of Safety
• /
• v.29 no.4
• /
• pp.78-84
• /
• 2014

Viscosity agents were added to water to improve extinguishing performance of low pressure water mist suppression system on wood cribs fire, and a small scale wood cribs fire experiment was conducted to measure the extinguishing performance. CMC and agar were used for viscosity agent and as the amount of viscosity agent enlarges, it showed the increase of the viscosity of aqueous solution and the decrease of the fluidity. On wood cribs fire experiment, the extinguishing efficiency was improved with supplemental viscosity agent as it enhanced the adhesive time of aqueous solution on the wood, and therefore expanded the contact time of fire surface. The surface tension of aqueous solution was decreased with the addition of agar which to be assumed as an increase factor of extinguishing efficiency. By the extinguishing experimental result, the most effective extinguishing agent was CMC 0.6 wt.%, with the flame suppression time and the extinguishing time were reduced by 70s and 93s respectively at this concentration.

• Ocean Science Journal
• /
• v.42 no.3
• /
• pp.165-170
• /
• 2007

The structure of the nematodes communities has been studied in the sediments on two sites located outside and under the layer of Ahnfeltia tobuchiensis (Kanno and Matsubara 1932; Makijenko 1970). Bottom sediments at the stations were represented by sands with a different degree of silting. Specific structure of nematodes at the stations was significantly different under the similar environmental conditions (water depth, dissolved oxygen saturation, salinity, temperature of the bottom layer and organic carbon content inside of the sediment). Nematodes dominated (75.7 %) in meiobenthos community under the layer of A. tobuchiensis where concentration of silt particles was 12 %. Representatives of the family Comesomatidae were dominant. Low index of species diversity and high Simpson domination index were detected in this community. Under a layer of A. tobuchiensis with the thickness of 30 cm concentration of the silt particles was 5.39 %; nematodes density was low and made 32.1 % of the general density of meiobenthos. Species of the families Xyalidae and Monoposthiidae were dominant. Outside of A. tobuchiensis, field percentage of silt particles was minimal (3.1 %) and representatives of families Cyatholaimidae and Axonolaimidae dominated. The specific structure of nematodes in this type of the ground is characterized by high index of species diversity and low level of domination.

• Korean Journal of Food Science and Technology
• /
• v.22 no.6
• /
• pp.716-719
• /
• 1990

The essential oils were isolated by steam distillation from 13 spices used for curry. Antimicrobial activity of essential oils for two strains of Gram(+) bacteria, Gram(-) bacteria, lactic acid bacteria, yeast and mold were investigated by agar diffusion method. 5 spice essential oils(clove, cumin, nutmeg, oregano, rosemary) having high antimicrobial activity were selected and their minimal inhibitory concentration(MIC) were measured. Very low concentration ($0.2{\sim}9\;mg/ml$) of 5 spice essential oils were sufficient to prevent microbial growth. The data show that Gram(+) bacteria were more sensitive to the antimicrobial compounds in spices than Gram(-). But though Gram(+) bacteria, lactic acid bacteria were less sensitive to the compounds than Gram(-).

• Mycobiology
• /
• v.37 no.4
• /
• pp.277-285
• /
• 2009

In this study, dual culture, poison agar, and direct methods were used to assess the ability of Trichoderma virens IMI-392430, T. pseudokoningii IMI-392431, T. harzianum IMI-392432, T. harzianum IMI-392433, and T. harzianum IMI-392434 to control Ceratocystis paradoxa, which causes the pineapple disease of sugarcane. The highest percentage inhibition of radial growth (PIRG) values were observed with T. harzianum IMI-392432 using two dual culture methods, 63.80% in Method I and 80.82% in Method II. The minimum colony overgrowth time was observed with T. harzianum IMI-392432 and the maximum was observed with T. pseudokoningii IMI-392431. Different concentrations of different day-old metabolites of Trichoderma isolates were tested against mycelial growth of C. paradoxa. The highest PIRG (84.685%) exhibited at 80% concentration of 30-day-old metabolites of T. harzianum IMI-392432 using the modified bilayer poison agar method. In the direct assay method the maximum mycelial growth weight (PIGW) was observed at the same concentration and the same day-old metabolites of T. harzianum IMI-392432. This study showed that Trichoderma isolates have a good antagonistic effect on C. paradoxa mycelial growth and T. harzianum IMI-392432 has the most potential to control the pineapple disease pathogen.