• Journal of Microbiology and Biotechnology
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• v.22 no.1
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• pp.84-91
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• 2012

Two staphylococcal lipases were obtained from Staphylococcus epidermidis S2 and Staphylococcus aureus S11 isolated from sebaceous areas on the skin of the human face. The molecular mass of both enzymes was estimated to be 45 kDa by SDS-PAGE. S2 lipase displayed its highest activity in the hydrolysis of olive oil at $32^{\circ}C$ and pH 8, whereas S11 lipase showed optimal activity at $31^{\circ}C$ and pH 8.5. The S2 lipase showed the property of cold-adaptation, with activation energy of 6.52 kcal/mol. In contrast, S11 lipase's activation energy, at 21 kcal/mol, was more characteristic of mesophilic lipases. S2 lipase was stable up to $45^{\circ}C$ and within the pH range from 5 to 9, whereas S11 lipase was stable up to $50^{\circ}C$ and from pH 6 to 10. Both enzymes had high activity against tributyrin, waste soybean oil, and fish oil. Sequence analysis of the S2 lipase gene showed an open reading frame of 2,067 bp encoding a signal peptide (35 aa), a pro-peptide (267 aa), and a mature enzyme (386 aa); the S11 lipase gene, at 2,076 bp, also encoded a signal peptide (37 aa), pro-peptide (255 aa), and mature enzyme (399 aa). The two enzymes maintained amino acid sequence identity of 98-99% with other similar staphylococcal lipases. Their microbial origins and biochemical properties may make these staphylococcal lipases isolated from facial sebaceous skin suitable for use as catalysts in the cosmetic, medicinal, food, or detergent industries.

• Korean Journal of Food Science and Technology
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• v.20 no.1
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• pp.95-99
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• 1988

The changes of texture, composition of cell wall polysaccharides, polygalacturonase (PG) activity and soaking effect during preserving of persimmon at various tempoeratures were estimated for the purpose of investigating the softening characteristics of persimmon fruit. The softening of persimmon was most promoted at $25^{\circ}C$, where in the higher temperature, at $45^{\circ}C$ it was inhibited. During softening adhesiveness increased, cohesiveness and gumminess decreased. This phenomenon was obvious at $25^{\circ}C$. By soaking in water at $50^{\circ}C,\;70^{\circ}C$ for 30 minutes PG activity and softening was inhibited. Ionically associated pectin (IAP) and covalently bounded pectin (CBP) fractionated from crude cell wall of fresh persimmon were respectively degraded about 60% by PG curde enzyme of softened persimmon. And the degraded ratio of polysaccharides composed of pentose and hexose was very similar to that of polyuronide.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.33 no.5
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• pp.463-468
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• 2000

This study was conducted to investigate the effects of Kluyveromyces fragilis, Candida utilis and brewer's yeast as an additive in formulated diets containing different fish meal levels ($55{\%} and 45{\%}$) on growth and body composition of juvenile Korean rockfish (Sebastes schlegeli). Juvenile rockfish (average weight, 2.6 g) were distributed into 24 tanks with 3 replication groups and fed eight isoproteic ($41{\%}$) and isolipidic ($11{\%}$) diets containing each level ($3{\%}$) of K. frayilis, C. utilis and brewer's yeast as an additive. Survival rate of fish was not affected by dietary fish meal level and yeast kind (P > 0.05). Weight gain of fish fed the control and diets containing C. utilis and brewer's yeast was not influenced by fish meal level (P > 0.05), Weight gain of fish fed the $55{\%}$ fish meal diet containing C. utilis and $45{\%}$ fish meal diets containing K. fragilis and C. utilis was lower than that of fish fed the control diet (P < 0.05). Feed efficiency and protein efficiency ratio of fish fed the control and diet containing brewer's yeast were not affected by fish meal level, but these value of fish fed the diets containing K, fragilis and C. utilis were lower in $45{\%}$ fish meal diets than in $55{\%}$ fish meal diets. Hepatosomatic index and liver lipid content of fish fed the diet containing C. utilis were decreased regardless of fish meal level (P < 0.05), Hemoglobin, hematocrit, red blood cell, plasma total protein and plasma total glucose were not affected by dietary fish meal levels and yeast supplements (P > 0.05). From the above results, it can be concluded that yeast supplement in this formulated diet for growth of juvenile rockfish is not necessary.

• Journal of Food Hygiene and Safety
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• v.17 no.2
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• pp.87-93
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• 2002

The removal of three pesticides which were residued in chinese cabbage was investigated during making process of Kimchi. When chinese cabbage was washed by water, the removal rates of three pesticides were 62.0%, 54.8% and 61.1% for pirimiphos-methyl, chlorpyrifos and prothiofos, respectively. Pesticides remaining in chinese cabbage after washing by water were also removed from 22.4% to 23.8% by salting. During the fermentation of kimchi for 24 days at 4。C, the pH was lowered 4.5 from 5.8 and the residual amount of pesticides was decreased by 51.4% to 69.4% for three Pesticides remaining after washing and salting On the other hand, when Kimchi was fermented under various temperature for 11 days, the residual amount of chlorpyrifos was decreased up to 29.2%, 45.0% and 77.3% of initial concentration at 4, 10 and 20 。C, respectively. The residual amount of chlorpyrifos in Kimchi was decreased up to 16.3% by heating at 100 。C for 6.5 minutes.

• Asian-Australasian Journal of Animal Sciences
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• v.22 no.9
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• pp.1311-1319
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• 2009

An experiment was conducted to determine the effects of soybean oil supplementation replacing tallow in pig diets at different stages of growth. One hundred and twenty crossbred (Landrace${\times}$Yorkshire${\times}$Duroc) pigs weighing 18 kg on average were selected. Pigs were randomly allotted to 12 pens of 10 pigs (5 pigs of each sex) each. Three pens were assigned to each of the four treatments: TA; tallow diet, TA-SO-80; switched from tallow to soybean oil diet at 80 kg average body weight, TA-SO-45; switched from tallow to soybean oil diet at 45 kg average body weight, and SO; soybean oil diet. Treatment SO was significantly lower in ADG than tallow diets (TA, TA-SO-80 and TA-SO-45) during the grower period (18 to 45 kg). However, treatment SO showed greatest compensation in ADFI and ADG during the finisher-2 period (after 80 kg body weight). ADFI and ADG and Gain/Feed for the total period were not significantly different among treatments. Loin area, back fat thickness, firmness and melting point of back fat were not significantly different. The levels of total cholesterol and low density lipoprotein+very low density lipoprotein cholesterol in serum were significantly lower in treatment SO than in treatments TA-SO-45, TA-SO-80 and TA. The level of serum triglyceride linearly increased as the length of the tallow feeding period increased. Serum immunoglobulin-G (IgG) level was significantly higher in the soybean oiltreatment than in other treatments. Major fatty acid composition of short rib muscle and back fat were significantly influenced by treatments. Contents of ${\alpha}$-linolenic acid (C18:3) and docosahexaenoic acid (DHA, C22:6) linearly increased as the soybean oil feeding period increased. In conclusion, soybean oil can be supplemented to the diet of pigs without significant effects on growth performance and carcass characteristics. The level of polyunsaturated fatty acids (PUFA), especially $\omega-3$ fatty acids in the carcass was increased by soybean oil supplementation.

• Horticultural Science & Technology
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• v.33 no.6
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• pp.869-876
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• 2015

Wild relative species of domesticated crops are useful genetic resources for improving agronomic traits. Cytogenetic investigations based on chromosome composition provide insight into basic genetic and genomic characteristics of a species that can be exploited in a breeding program. Here, we used FISH analysis to characterize the ploidy level, chromosome constitution, and genomic distribution o f 5S and 4 5S r ibosomal DNA (rDNA) in four wild Cucurbitaceae species, namely, Citrullus lanatus (Thunb.) Mansf. var. citroides L. H. Bailey (2n = 22), Melothria japonica Maxim. (2n = 22), Sicyos angulatus L. (2n = 24), and Trichosanthes kirilowii Maxim. (2n = 66, 88, 110 cytotypes), collected in different areas of Korea. All species were diploids, except for T. kirilowii, which included hexa-, octa-, and decaploid cytotypes (2n = 6x = 66, 8x = 88, and 10x = 110). All species have small metaphase chromosomes in the range of $2-5{\mu}m$. The 45S rDNA signals were localized distally compared to the 5S rDNA. C. lanatus var. citroides and M. japonica showed one and two loci of 45S and 5S rDNA, respectively, with co-localization of rDNA signals in one M. japonica chromosome. S. angulatus showed two co-localized signals of 5S and 45S rDNA loci. The hexaploid T. kirilowii cytotype showed five signals each for 45S and 5S rDNA, with three being co-localized. This is the first report of hexaploid and decaploid cytotypes in T. kirilowii. These results will be useful in future Cucurbitaceae breeding programs.

• Applied Biological Chemistry
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• v.26 no.1
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• pp.41-46
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• 1983

The characteristics of crude polyphenol oxidase extracted from mushroom[Tricholoma matsutake(S. Ito et Imai) Sing.] were investigated. The enzyme showed highest affinity to pyrogaroll among trihydroxyphenols. Except for o-diphenols the enzyme was inactive in di-and monophenols. The optimum pH was about 4 and the optimum temperature ranged from 45 to $55^{\circ}C$. The enzyme activity was completely inhibited by $70^{\circ}C$ heat treatment for 2 min. $Cu^{++}$, $Fe^{++}$ and $Mg^{++}$ activated the enzyme at low concentration($10^{-1}mM$), but inhibited at high concentration (1mM). The most potent inhibitors were Na-diethyldithiocarbamate, L-ascorbic acid, L-cysteine and NaCl. The Km value with pyrogaroll was 0.88mM.

• Journal of Microbiology and Biotechnology
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• v.21 no.11
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• pp.1116-1122
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• 2011

In this study, site-directed mutagenesis was performed on the ${\beta}$-agarase AgaA gene from Zobellia galactanivorans to improve its catalytic activity and thermostability. The activities of three mutant enzymes, S63K, C253I, and S63K-C253I, were 126% (1,757.78 U/mg), 2.4% (33.47 U/mg), and 0.57% (8.01 U/mg), respectively, relative to the wild-type ${\beta}$-agarase AgaA (1,392.61 U/mg) at $40^{\circ}C$. The stability of the mutant S63K enzyme was 125% of the wild-type up to $45^{\circ}C$, where agar is in a sol state. The mutant S63K enzyme produced 166%, 257%, and 220% more neoagarohexaose, and 230%, 427%, and 350% more neoagarotetraose than the wild-type in sol, gel, and nonmelted powder agar, respectively, at $45^{\circ}C$ over 24 h. The mutant S63K enzyme produced 50% more neoagarooligosaccharides from agar than the wild-type ${\beta}$-agarase AgaA from agarose under the same conditions. Thus, mutant S63K ${\beta}$-agarase AgaA may be useful for the production of functional neoagarooligosaccharides.

• Korean Journal of Microbiology
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• v.49 no.1
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• pp.71-77
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• 2013

This study was carried out to investigate the characteristics of Chungkookjang depending on different soybeans and fermentation temperatures using Bacillus amyloliquefaciens C2 isolated from homemade Chungkookjang. The highest protease activity was 854 U/g in yellow soybean Chungkookjang and 847 U/g in black soybean Chungkookjang at $35^{\circ}C$. The highest amylase activity was 3.87 U/g at $40^{\circ}C$ in yellow soybean Chungkookjang and 4.96 U/g at $45^{\circ}C$ in black soybean Chungkookjang. The highest reducing sugar content was 16.11 mg/g at $40^{\circ}C$ in yellow soybean Chungkookjang and 19.08 mg/g at $45^{\circ}C$ in black soybean Chungkookjang. The highest amino type nitrogen content was 420 mg%/g in yellow soybean Chungkookjang and 194 mg%/g in black soybean Chungkookjang at $40^{\circ}C$. The highest pH was 7.92 at $40^{\circ}C$ in yellow soybean Chungkookjang and 7.59 at $45^{\circ}C$ in black soybean Chungkookjang. The highest number of viable cell was 9.3 log CFU/g at $40^{\circ}C$ in yellow soybean Chungkookjang and at $35^{\circ}C$ in black soybean Chungkookjang. On the other hand, the lowest ammonia type nitrogen content was 225 mg%/g at $45^{\circ}C$ in yellow soybean Chungkookjang and 80 mg%/g at $40^{\circ}C$ in black soybean Chungkookjang. Yellow soybean Chungkookjang showed high protease activity, pH and amino type nitrogen, whereas black soybean Chungkookjang showed high amylase activity and reducing sugar.

• Journal of Embryo Transfer
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• v.21 no.4
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• pp.339-344
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• 2006

This study was to investigate the optimal short-term storage diluents for goat spermatozoa. Semen was collected with electro-ejaculation from two goats. The collected semen was diluted in BTS and centrifuged at 500 g for 5 minutes. The supernatant was discarded and diluted with BTS, Modena or Triladyl$^{(R)}$ and stored at 4 or $17^{\circ}C$ for 8 days. The motility of spermatozoa in BTS and Modena stored at $4^{\circ}C$ was rapidly decreased at day 1. The motility of spermatozoa in BTS at $17^{\circ}C$ was decreased to 30$\sim$45% at day 2. In Modena at $17^{\circ}C$, the inappropriate motility fur artificial insemination (AI) was reached at day 4. The spermatozoa stored in Triladyl$^{(R)}$ at 4 or $17^{\circ}C$ were more viable and higher motility up to day 4. In conclusion, liquid storage of goat spermatozoa in Triladyl$^{(R)}$ at 4 or $17^{\circ}C$ for 4 days showed permissible viability for AI.