• Food Science of Animal Resources
• /
• v.21 no.4
• /
• pp.349-357
• /
• 2001

The effects of dietary conjugated linoleic aicd on pork quality was investigated using sixty four pigs. CLA was synthesized by alkaline isomerization method with corn oil. Pigs were devided into 4 treatment groups(16 pigs/group) arid subjected to one of four treatment diets(0, 0.1, 0.2, and 0.3% CLA diets) for 2 weeks before slaughter. Pork loin and belly were collected from the animals(105∼110kg body weight) slaughtering at the commercial slaughter house. Pork loin and belly meat were aerobic packaged and then stored during 2. 5. 8. 11 and 13 days at 4$\^{C}$ refrigerator. Samples were analysed for meat color, texture and sensory characteristics. There were no diference in meat color(L*, a*, b*), texture and sensory property among control and CLA treatment (s), and no changes as the storage period passed. This results mean that feeding CLA to pork doesn't change the meat color and texture of the pork what consumers consider when they buy some meat. Especially, feeding CLA to pork didn't transform sensory property of the pork. We considered these result as no problem in the pig fed with CLA.

• Food Science and Preservation
• /
• v.8 no.3
• /
• pp.320-325
• /
• 2001

In fermentation characteristics, R2 was suitable for fast start and fermentation, while UCD530 was tool suitable far complete fermentation at 25$^{\circ}C$. T73 and AC- strains produced much more total acid compared to other strains and it was concerned with producing large amount of succinic acid and acetic acid. OC-2, UCD530, Beaujolais, and BC strains revealed low fermentation efficiency (below 62.0%), but EC1118, RC212, T73 and BM45 strains showed opposit result (above 70.0%). D254 and Wadenswil 27 seemed to have excellent cohesive ability because these two yeast strains made somewhat hard precipitation at the bottom after complete fermentation. T73 and CEG gave higher amounts of acetic acid (above 630 mg/L), while UCD530, W-3 and Beaujolais recorded low concentration (below 200 mg/L). In sulfur dioxide tolerance, preferable culturing temperature and times were 25$^{\circ}C$ and 72 hr respectively. The strains R2, BM45 and L2056 revealed high sulfur dioxide tolerance (above 30mg/L), white 71B, Wadenswil 27 and Beaujolais showed the opposite result (below 5mg/L)

• Journal of the Korean Wood Science and Technology
• /
• v.33 no.6 s.134
• /
• pp.79-86
• /
• 2005

Aspen wood (Populus tremuloides, L.) was biotreated with Ceriporiopsis subvermispora for 1, 2, 4, and 6 weeks to observe the physical/chemical modification of wood components. Milled wood lignins (MWLs) isolated from each decayed wood were analyzed by gel permeation chromatography (GPC) and nitrobenzene oxidation (NBO). As fungal treatment was progressed, lignin contents continuously decreased up to 20% after 6-week treatment. The lignin polymer could be fragmented to low-molecular phenolics, which make an enhancement of alkali solubility. Holocellulose contents were not affected severely during the period of fungal treatment, only reduction of 5~6% compared to the control. Xylose contents were decreased gradually from 23.4% to 18% after 6 weeks, whereas alpha-cellulose remained almost unchanged. Gel permeation chromatography (GPC) indicates that molecular weight of lignin undergoes a slight decrement for 4 weeks of fungal treatment. Nitrobenzene oxidation revealed that total yield of NBO products of lignins were lowered ca 20% after fungal treatment. Sum of syringaldehyde and syringic acid are remarkably decreased. However, increment of sum of vanillin and vanillic acid was surprisingly observed. These results work as indirect evidence that a specific lignolytic reaction, maybe selective demethoxylaytion of S-lignin, can occur during fungal treatment of aspen wood by C. subvermispora.

• Korean journal of food and cookery science
• /
• v.29 no.6
• /
• pp.725-731
• /
• 2013

This study investigates the quality of strawberry jam containing different quantities of strawberry. Strawberry jam was prepared by the addition of 70-30%(w/w) strawberry puree, Sweetness, pH, total acidity, color, anthocyanin and pectin content, texture, free sugar, and organic acid content of the samples were measured. Decrease in the quantity of the strawberry puree led to a decrease in the following: total acidity(significance value p<0.05), anthocyanin, pectin, total free sugar, frutose, glucose, sucrose, and, organic acid content, namely oxalic acid, citric acid, malic acid, succinic acid, and formic acid. A texture profile analysis showed reduction in the hardness, gumminess, and chewiness of the jam. At the same time, decrease in the puree quantity also led to an increase in the sweetness, pH, L-value, a-value and b-value(significance value p<0.05) of the jam. These results promote, the consumption of fruit that are high in fruit, low in sugar, and do not contain any chemical additives.

• Journal of the Korean Society of Food Science and Nutrition
• /
• v.31 no.4
• /
• pp.547-552
• /
• 2002

Characteristics of components related to meat taste of broiler and Korean native chicken (KNC) were investigated. Carnosine was detected much more in the breast meat of KNC at 28 weeks of age and in the leg meat of KNC over 6 weeks of age than broiler. Glutamic acid was much contained in the leg meat of KNC over 11 weeks of age. In the case of breast meat, the content of glutamic acid was higher in KNC over 6 weeks of age than that of others. The ratio of good-tasting amino acid to bitter-tasting amino acid was higher in KNC over 11 weeks of age than broiler. Concentration of IMP in KNC over 15 weeks of age was higher than that of broiler.

• Korean Journal of Medicinal Crop Science
• /
• v.7 no.4
• /
• pp.245-250
• /
• 1999

Callus growth of fusaric aicd-tolerance cell lines was different depending on fusaric acid concentrations. But callus growth on medium with fusaric acid was higher than that on medium without fusaric acid. Especially, RF-9, RF-11 and RF-15 showed high callus growth at $100\;{\mu}M$ fusaric acid. After subculturing on medium without fusaric acid for 5 weeks, fusaric acid -tolerant stability was investigated. Cell lines at $10{\mu}M$ fusaric acid were showed over 60% callus growth, callus growth rate at $100{\mu}M$ fusaric acid was decreased until 30-80% of control. Regeneration capacity of fusaric acid-tolerant cell lines was different depending on fusaric acid concentrations. Thirteen cell lines regenerated the shoot over at $50{\mu}M$ fusaric acid, and only two cell lines were not regenerated.

• KSBB Journal
• /
• v.19 no.1
• /
• pp.17-26
• /
• 2004

In this study the extracellular production of 5-aminolevulinic aicd (ALA) by recombinant E. coli BL2l (DE3) pLysS harboring the plasmid pFLS45 are investigated. Optimum concentrations of succinic acid and glycine for cell growth and ALA production were found to be 30 mM and 15 mM, respectively. Levulinic acid (LA) as an inhibitor of ALAD was added to the culture medium in the end of exponential cell growth phase and its optimum concentration was 30 mM. Growth of recombinant E. coli BL2l (DE3) pLysS (pFLS45) was largely dependent upon the pH value of culture medium. When the pH of culture medium was in the range of 6.0 and 6.5, high cell mass and ALA production were obtained. IPTG induction for the expression of the fusion gene did not enhance the production of ALA. Recombinant cell grew at 30't faster than at 37$^{\circ}C$, but ALA productivity was lower than at 37$^{\circ}C$. Repeated addition of glycine, succinic acid, and LA increased the production of ALA and the inhibition of intracellular ALA dehydratase activity, with up to 1.3 g/L ALA having been produced in the cultivation.

• Korean Journal of Veterinary Research
• /
• v.36 no.3
• /
• pp.541-550
• /
• 1996

Tetracycline antibiotics have been widely used not only therapeutics but feed additives. There are many methods for the isolation and determination of tetracycline antibiotics in animal muscle tissue. But those methods take much time and labor, so it is difficult to analyse many samples simultaneously. A rapid isolation method and liquid chromatographic determination of tetracycline antibiotics in animal muscle tissue (bovine, porcine, chicken) is presented. Blank control and tetracyclines fortified samples (0.5g) were blended with $C_{18}$ containing 0.05g each of oxalic acid and disodium ethylenediaminetetraacetate. After homogenize, homogenate was transferred to glass column made from 10ml glass syringe and compressed to 4~4.5ml volume. A column made from the $C_{18}$/meat matrix was washed with hexane (8ml) and dichloromethane (8ml, if needed), following which the tetracyclines were eluted,vith methanol or 0.01M methanolic oxalic acid (8ml). The eluates containing tetracyclines analytes were free from interfering compounds when analysed by HPLC with UV detection (photodiode array at 360nm). Standard curve for each tetracycline showed a linear response at the range of $0.05{\sim}1.0{\mu}g/ml$ and tetracycline antibiotics were eluted within 4ml of eluted volume. All tetracycline antibiotics except tetracycline were stable during the concentration process at $40^{\circ}C$ and time required for concentration was 3~4 hours. Fortified samples containing oxalic aicd and EDTA represented more good recoveries than those of not-contained sample. Recoveries were 91.8~110.1% (oxytetracycline; OTC), 57.7~79.5% (tetracycline; TC), 78.1~88.6% (chlortetracyclines; CTC) and 88.4~100.6% (doxycycline; DC) in pork tissue, 101.1~126.8% (OTC), 66.4~75.4% (TC), 79.2~88.1% (CTC) and 69.3~86.7% (DC) in beef tissue, and 90.8~95.6% (OTC), 66.2~84.4% (TC), 75.7~77.2% (CTC) and 55.6~80.7% (DC) in chicken muscle tissue. The detection limits validated in muscle tissue by this method were $0.05{\mu}g/g$ for OTC and TC, and $0.1{\mu}g/g$ for CTC and DC.

• Journal of Life Science
• /
• v.30 no.2
• /
• pp.169-177
• /
• 2020

For this study, we prepared organic solvent fractions from methanol extracts of Houttuynia cordata and Lespedeza cuneate, and analyzed their chemical components and various biological functions such as anti-oxidation, angiotensin-converting enzyme (ACE) inhibition, and α-glucosidase inhibitory activities. We found that DPPH radical scavenging activity was highest in the ethyl acetate fractions of Houttuynia cordata (90.8%) and Lespedeza cuneata (91.2%), whereas ABTS radical scavenging activity was highest in the ethyl acetate fractions of Houttuynia cordata (86.1%) and the chloroform fractions of Lespedeza cuneata (95.6%). FRAP activity was highest in the ethyl acetate fraction of Houttuynia cordata (360.1 mg TE/g) and Lespedeza cuneata (239.2 mg TE/g). ACE inhibitory activity was highest in the chloroform fraction of Houttuynia cordata (13.2%) and Lespedeza cuneata (35.2%). And, α-glucosidase inhibitory activity was highest in the ethyl acetate fraction of Houttuynia cordata (56.3%), and the water residue of Lespedeza cuneata (93.6%). Finally, we investigated the DPPH radical scavenging activity of 20 types of pure compounds identified in Houttuynia cordata and Lespedeza cuneate. The results show that quercetin demonstrates the highest DPPH radical scavenging activity. Overall, these results help us to understand the functional chemical components of Houttuynia cordata and Lespedeza cuneate and the biological effects of these components.

• Korean journal of food and cookery science
• /
• v.7 no.1
• /
• pp.15-25
• /
• 1991

The effects of lactic acid bacteria on the chemical and microbial changes of fermented kimchi at various temperatures were studied. Kimchi was homogenized and was sterilized by ultra violet, then Lactobacillus plantarum, Leuconostoc mesenteroides, Pediococcus acidilactici, Lactobacillus brevis and the mixture of there bacteria inoculated on sterilized kimchi, respectively. The measurement of pH and total acidity, quantitative analysis of volatile organic acids and nonvolatile organic acids by gas chromatography were investigated while inoculated kimchi were fermented at $30^{\circ}C$, $21^{\circ}C$, $14^{\circ}C$ and $7^{\circ}C$. Sample I (original kimchi homogenate), Sample III (inoculated with Leuconostoc mesenteroides) and Sample Ⅵ (inoculated with mixed lactic acid bacteria) were alike in that changes of pH and total acidity and especially, these phenomena were prominent at $14^{\circ}C$. Formic, acetic and heptenoic acid as volatile organic acid were detected by GC, and these acids formed mainly by Leuconostoc mesenteroides and lactobacillus brevis. Sample III was more higher content than other samples at $14^{\circ}C$. As nonvolatile organic acid, lactic acid in all samples, citric acid in sample III at $21^{\circ}C$and $14^{\circ}C$, succinic acid in sample I at $30^{\circ}C$, $21^{\circ}C$, $14^{\circ}C$ and sample V at $30^{\circ}C$ were detected by GC.