• Journal of Ginseng Research
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• v.7 no.1
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• pp.80-87
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• 1983

In an endeavour to elucidate effects of ginseng on some characteristics of enzymes, malate dehydrogenase (EC 1.1.1.37) was chosen as a model enzyme and effects of ginseng saponin on the enzyme such as optimum pH, product inhibition, optimum temperature and the activity was investigated. The product inhibition by NADH-a reaction product of the enzyme-was increased 33% by 0.3% ginseng saponin. And the optimum pH of the enzyme was 8.3 but in the presence of 0.3% ginseng saponin it increased to 8.5. The enzyme activity and the optimum temperature was not affected by ginseng saponin in the concentration of 1.0% and 0.3%, respectively. In this work, the possibility of contribution of ginseng saponin to the adaptogen activity is suggested; Potentiation of the regulatory activity of an enzyme may contribute to the normalization of the physiological state and consequently may increase the nonspecific resistance of an organism.

• Microbiology and Biotechnology Letters
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• v.22 no.3
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• pp.259-265
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• 1994

A bacteriocin-producing lactic acid bacteria was isolated from contaminated milk products, which was identified by using the API50 CH kit as Lactococcus lactis subsp. lactis with reliability of 98%. Fatty and analysia of the cell membrane showed that this strain contained same fatty acids profiles as type strain, Lactococcus lactis subsp. lactis ATCC 19435. The bacteriocin of Lactococcus sp. HY 449 showed relatively wide range of inhibition spectrum against gram positive and some gram negative bacteria such as Escherichia coli and maintained the inhibitory activity between pH2.0 and pH9.0 The thermostability of this bacteriocin was higher in acidic solution than in distilled water and was stable at 60$\circ $C for 1 hour.

• Korean Journal of Veterinary Service
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• v.20 no.2
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• pp.161-168
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• 1997

This study was undertaken to determined the sulfamethazine residues In urine, serum and muscle of slaughtered pigs(n: 230) by the method of TLC, EEC-4-plate and HPLC. 1. Inhibition diameter characteristics of reference bacterial substance by EEC-4-plate method and antibacterial inhibition zone was appeared sulfonamides in BS pH 7.2 2. Residual sulfamethazine was detceted from 7 serum(3.04%) and 10 urine(4.35%) by TLC test and concentration of residues was higher In urine than serum. 3. Residual sulfamethazine was detected from 9 muscle(3.91%) by EEC-4-plate method. 4. Positive samples by TLC test and EEC-4-plate method were exceed 0.1ppm quantitative analysis from 7 muscle(3.04%).

• Korean Journal of Microbiology
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• v.22 no.4
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• pp.229-234
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• 1984

A modified E. coli trp operon, $trpL({\Delta}att)\;trpE^{FBR}$, was conjugally transfered into Klebsiella pneumoniae $KC_{100}\;(Phe^-,\;Tyr^-,\;Trp^-,\;Rif^r,\;Kam^r)$ by in vivo cloning using the hybrid plasmid $R_{6}K::$ Mucts 61 with a transfer frequency of $5.2{\times}10^{-7}$. Two K. pneumoniae transconjugants, $KUA_{701}\;and\;KUA_{702}$, were isolated. The characters of attenuation control-free and resistance to feedback-inhibition which are characteristics of donor C. coli trp operon were normally expressed in the $KUA_{701}.\;However,\;KUA_{702}$ retained only the feedback-inhibition resistant character. $Trp^+$ phenotype and ampicillin resistant character were completely stable in the transconjugants, but streptomycin resistant character was lost in the transconjugants.

• Mycobiology
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• v.49 no.5
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• pp.498-506
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• 2021

An endophytic fungus strain DYSJ3 was isolated from a stem of Aphanamixis grandifolia Blume, which was identified as Aspergillus versicolor based on the morphological characteristics, internal transcribed spacer (ITS) and calmodulin gene sequences analyses. A. versicolor DYSJ3 exhibited strong antagonistic activity against Colletotrichum musae, C. gloeosporioides and Fusarium oxysporum f. sp. cubense with the inhibition rates of 61.9, 51.2 and 55.3% respectively. The antifungal metabolites mainly existed in the mycelium of A. versicolor DYSJ3, and its mycelial crude extract (CE) had broad-spectrum antifungal activities against plant pathogenic fungi. The CE had a good thermal stability, and the inhibition rate of 100 mg/mL CE against C. musae was above 70.0% after disposing at 120 ℃ for 1 h. Five secondary metabolites were isolated from the CE and identified as averufanin, ergosterol peroxide, versicolorin B, averythrin and sterigmatocystin. Activity evaluation showed versicolorin B exhibited inhibitory effects on the mycelial growth and conidial germination of C. musae, and sterigmatocystin had a weak inhibitory effect on the mycelial growth of C. musae.

• Korean journal of food and cookery science
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• v.24 no.6
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• pp.849-855
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• 2008

DPPH radical scavenging activities were 66.80% by hot water extract and 41.86% by 80% methanol extract. Inhibitions of angiotensin I-converting enzyme (ACE) were 91.09% by hot water extract and 75.20% by 80% methanol extract. In this study, Sulgidduk samples were prepared with 1, 3, 5, and 7% concentrated sweet pumpkin powder (CSPP), and a control were examined for quality characteristics such as moisture content, water activity, color, textural characteristics, and sensory qualities, in order to determine the optimal ratio of CSPP in the formulation. The samples containing CSPP exhibited significantly higher moisture content than the control group. Water activity was not significantly different among the Sulgidduk samples. For the color, the control group presented significantly higher lightness as compared to the samples containing CSPP. The samples containing 1 and 3% CSPP had significantly higher greenness than the samples containing 5 and 7% CSPP. Yellowness increased as the level of CSPP content increased. In terms of textural characteristics, hardness, gumminess, and chewiness were highest at the 1% substitution level, while lowest at the 3% level. The CSPP samples presented significantly higher adhesiveness, springiness, and cohesiveness than the control group. In the consumer acceptance and characteristic intensity rating test, the control group showed significantly higher color and flavor as compared to the CSPP samples. Pumpkin flavor, delicious taste, and off-flavor increased with increasing amounts of CSPP. Softness, overall acceptability, and gumminess were not significantly different among the various samples tested. Sweetness was highest at the 5% substitution level, while lowest at the 1% level. In conclusion, the results indicate that substituting $3{\sim}5%$ CSPP to Sulgidduk is optimal, providing good DPPH radical scavenging activity and inhibition of ACE as well as reasonably high overall acceptability.

• Journal of Korean Medicine for Obesity Research
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• v.18 no.2
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• pp.64-73
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• 2018

Objectives: This study investigated the effect on microbial ecology, fermentation characteristics and anti-obesity of Platycodon grandiflorum (PG) fermentation with salt. Methods: PG was fermented for four weeks with 2.5% salt and the characteristics of fermented PG were performed by measuring pH, total sugar content, viable bacteria number and microbial profiling. Also, we measured total polyphenol, flavonoid and the percent of inhibition of lipase activity and lipid accumulation. Results: Salt added to PG for fermentation had an effect on pH, total sugar, total and the number of lactic acid bacteria. Total sugar and pH were reduced and number of total and lactic acid bacteria were increased after fermentation. The majority of bacteria for fermentation were Lactobacillus plantarum, Leuconostoc psedomesenteroides and Lactococcus lactis subspecies lactis regardless of salt addition. However, microbial compositions were altered by added salt and additional bacteria including Weissella koreensis, W. viridescens, Lactobacillus sakei and Lactobacillus cuvatus were found in fermented PG with salt. Total flavonoid was increased in fermented PG and lipid accumulation on HepG2 cells treated with fermented PG was reduced regardless of salt addition. Moreover, fermented PG without salt suppressed lipase activity. Conclusions: Addition of salt for PG fermentation had influence on fermentation characteristics including pH and sugar content as well as number of bacteria and microbial composition. In addition, fermented PG showed anti-obesity effect by increasing flavonoid content and inhibition of lipase activity and lipid accumulation.

• Korean Journal of Weed Science
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• v.16 no.2
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• pp.122-131
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• 1996

The inhibition characteristics of chlorsulfuron [CHL, 2-chloro-N-[{ (4-methoxy-6-methyl-1,3,5-triazin-2-yl)amino}carbonyl]benzenesulfonamide] and imazaquin [IMA, 2-{4,5-dihydro-4-methyl-4-(1-methy-lethyl)-5-oxo-1H-imidazol-2-yl}-3-quinolinecarboxylic acid] on acetolactate synthase(ALS) activity of corn plants were investigated. CHL and IMA rapidly inhibited ALS activity of corn plants in vitro. Their $I_{50}$ values for ALS activity were 100nM and $5{\mu}M$, respectively, indicating that CHL had 50 times more inhibitory effect on ALS activity than IMA. The first applied herbicide had a dominant inhibitory effect on ALS activity when the two herbicides were applied sequentially. Branched-chain amino acids, valine(Val), leucine(Leu), and isoleucine(Ile) showed a feedback inhibition on ALS activity ; Val or Leu had a more inhibitory effect on ALS activity than Ile. Branchedchain amino acids and CHL or IMA exhibited an additive effect on inhibiting ALS activity. This suggests that branched-chain amino acids inhibit ALS activity by a different mechanisms) from that of CHL or IMA. Apparent ALS activity, which was measured on the basis of the conversion of pyruvate to acetolactate, was decreased by the addition of 2-ketobutyrate into the ALS reaction mixture in a concentration-dependent manner. In addition, kinetic studies revealed that CHL acts as a noncompetitive inhibitor, while IMA acts as an uncompetitive inhibitor to ALS with respect to pyruvate.

• Korean Journal of Food Science and Technology
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• v.37 no.1
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• pp.23-29
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• 2005

To investigate potential characteristics of clay minerals (illite, kaolin, zeolite, vermiculite, and bentonite) for food industry application, antioxidative properties of clay minerals, electron-donating ability (EDA), peroxide value (POV), and thiobabituric acid (TBA) were measured, and antimicrobial activity against several food spoilage microorganisms were evaluated by minimum inhibition concentration (MIC) method. Changes in components by cooking clay minerals added to stored rice were measured by GC-MS. DPPH (1,1-diphenyl-2-picrylhydrazyl) analysis results revealed bentonite has strongest EDA at 20.6%. Antioxidant activities measured based on POV were similar to DPPH results. Induction period of linoleic acid with vermiculite was longest among. TBA results revealed zeolite hasstrongest antioxidant ability. Growth inhibition against E. coli and S. aureuswas observed in illite, vermiculite, and zeolite. Aroma components indicated decrease in hex anal, pent anal, non anal, linoleate, stearic acid, and oleic acid when clay minerals were added to stored rice. These results indicate that several clay minerals have antioxidative and antimicrobial abilities and improve flavor profiles in stored rice.

• The Korean Journal of Food And Nutrition
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• v.11 no.1
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• pp.41-46
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• 1998

The aims of this study are conducted to investigate the effect of Duck's egg oil no new functional characteristics in the diabetics induced by streptozotocin(STZ) and inhibition of antitumor activity toward Sarcoma-180 bearing mice. Serum glucose content by administration of Duck's egg oil in diabetic group induced by STZ were maintained with normal state than that of control. Phospholipid and triglyceride contents were significant decrease in group of administration with Duck's egg oil than that of control group. Total cholesterol, LDL + VLDL cholesterol and atherosclerotic index were decreased in the group of treatment of Duck's egg oil when does level compared with that of control group. On the other hand, the growth inhibition of the Sarcoma-180 showed the highest level of 63.89% when 150㎎/㎏ Duck's egg oil administrated. The life prolongation effect showed 19.7% at dose of 150㎎/㎏.