• Korean Journal of Microbiology
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• v.39 no.1
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• pp.8-15
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• 2003

To evaluate the effects of slow release fertilizer and chemical dispersant on oil biodegradation, mesocosm studies were conducted on sand seashore. The rapid removal rates (85%) of aliphatic hydrocarbons and the simultaneous decreases of n-$C_{17}$/pristane (69%) and $n-C_{18}/phytane$ (61%) ratios by the addition of slow-release fertilizer (SRF) within 37 days of experiment indicated that SRF could enhance the oil degrading activity of indigenous microorganisms in sand mesocosm. Although the growth of heterotrophic bacteria and petroleumdegrading bacteria in the mesocosm treated with $Corexit 9527^{R}$ was stimulated, the biological oil removal based on the ratios of $Corexit 9527^{R}$ and $n-C_{18}/phytane$ was inhibited. Removal rates of aliphatic hydrocarbons (56%), and n-$C_{17}$/pristane (27%) and $n-C_{18}/phytane$ (17%) ratios by the addition of chemical dispersant $Corexit 9527^{R}$ were similar or lower than those values of control (50, 60, 46%), respectively. The biodegradation activity, however, when simultaneously treated with SRF and $Corexit 9527^{R}$, was not highly inhibited and even recovered after the elimination of chemical dispersant. From these results it could be concluded that the addition of SRF enhanced the oil removal rate in oligotrophic sand seashore and chemical dispersant possibly inhibit the oil biodegradation. Hence, in order to prevent the unrestrained usage of chemical dispersant in natural environments contaminated with oil, the National Contingency Plan of Oil Spill Response should be carefully revised in consideration of the application for bioremedaition techniques.

• Korean Journal of Environmental Agriculture
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• v.40 no.4
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• pp.322-329
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• 2021

BACKGROUND: The fungicide of benomyl, a benzimidazole group, has been commonly used for pesticides against fungal diseases in the world. However, benomyl is rapidly hydrolyzed in the environment after using to control plant diseases and has adverse effects by generating carbendazim, which is toxic to plants, humans, and the environment. METHODS AND RESULTS: In this study, the decomposition effect of carbendazim, a degradation product of benomyl was conducted in pot and field after making a prototype of benomyl-degrading microbial agent (BDMA). We found that the carbendazim-degrading microbial agent (CDMA) (10⁵, 10⁶, and 10⁷ cfu/g soil) decomposed carbendazim by 50% or more in all the treatments, compared to the untreated control in the pot tests after four weeks. The effect of 100% decomposition of carbendazim was observed at 7 days after treatment, when the prototype of BDMA was apllied at 10-folds dilution in the field. The decomposition effect at more than 60% and plant growth promoting effect were observed after 7 days of the treatment, compared with the untreated group in the second field experiment,treated with commercially available concentrations of 500-folds and 1,000-folds. CONCLUSION(S): These results might represent that the BDMA would decompose carbendazim effectively, a decomposition product of the fungicide benomyl, remaining in agricultural area, and it could be utilized practically by using a low dilution rate.

• Korean Journal of Food Science and Technology
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• v.35 no.4
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• pp.628-634
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• 2003

To investigate the effects of storage and pasteurization temperature on the quality of kiwi juice $(13.5^{\circ}Brix)$, the Kiwi juice was pasteurized at 65, 75 and $85^{\circ}C$ for 15 sec. The microbial, physicochemical measurements and sensory evaluations were conducted at the same condition during storage at 4 and $25^{\circ}C$ for 30 days. Most of the vegetative bacteria cells in kiwi juice were destroyed by heat treatment over $65^{\circ}C$, and they did not actively grow in kiwi juice after pasteurization. The D values of bacteria in kiwi juice by tubular type of heating exchange were 4.17, 1.47 and 0.81 sec at 65, 75 and $85^{\circ}C$, respectively. The growth of microorganisms during storage were not detected in the most samples. The amounts of vitamin C decreased as the pasteurization-storage-temperature and storage time increased. While reducing sugar increased as the pasteurization-storage temperature-storage time increased, it decreased rapidly after 20 days of storage. Hunter's color values L, a and b of stored kiwi juice were decreased at all storage conditions, browning reaction rate increased as the pasteurization-storage-temperature was decreased.

• Applied Biological Chemistry
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• v.32 no.4
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• pp.424-434
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• 1989

The rationale for the use of fungi in treating waste streams from food processing plants I~as been that of incorporating the dissolved and suspending nutrients into a macroscopic organism which can be filtered out readily. In order for a process using fungi to meet these objectives we examined a strain of fungi, Aspergillus fumigatus, which grew well on a variety of polysaccharide-containing materials and showed both efficient BOD removal and high quality protein recovery. In this experiment the fungal choice was based on the laboratory screening studies where the criteria used was BOD and COD reduction, growth response, mycelial yield, and the ability to compete with the natural flora. In the fermentation system used far the continuous culture of Aspergillus fumigatus the best combination of operating variables, inoculum ratio, temperature, initial pH, fermentation time and agitation rate was 5%(v/v), $35{\sim}40^{circ}C,\;pH\;4.5{\sim}5.0$, 2days and 150rpm, respectively. The fungus reduced BOD and COD to 94.0 and 90.4%, respectively and 3.15g of dry mycelium per liter of alcohol waste was harvested during 48hr of incubation time. The protein efficiency ratios for the control diet and the experimental diet containing the fungal protein were $3.42{\pm}0.15$ and $3.40{\pm}0.43$, respectively.

• Journal of Dairy Science and Biotechnology
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• v.17 no.1
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• pp.1-10
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• 1999

A bacteriocin produced by Lab. acidophilus GP4A isolated from fecal contents of pig was characterized. Lab. acidophilus GP4A produced a heat-stable and pH-resistant bacteriocin, which was hydrolyzed by trypsin and pepsin and active against various microorganisms. Lab. acidophilus GP4A produced bacteriocin at maximum rate when grown in MRS broth(pH 6.5${\sim}$7.5) at$37^{\cric}C$ or $40^{\cric}C$. The bacteriocin produced by Lab. acidophilus GP4A inhibited the growth of Lactobacillus delbrueckii subsp. lactis 4794 in early logarithmic phase. The bacteriocin was purified by ammonium sulfate precipitation and Octyl sepharose CL-4B column chromatography. The purification resulted in a final yield of 21.7% and a 13.6-fold increase in the specific activity.

• Asian-Australasian Journal of Animal Sciences
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• v.18 no.12
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• pp.1727-1734
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• 2005

The fermentation characteristics and mono- and di-saccharides compositions during the early stage of ensiling were studied with a temperate grass, Italian ryegrass (Lolium multiflorum Lam.) and a tropical grass, guineagrass (Panicum maximum Jacq.). The laboratory silos were kept in the room set at 25$^{\circ}C$, and then were opened on 0.5, 1, 2, 3, 5 and 7 days (14 days in Italian ryegrass) after ensiling, respectively. The Italian ryegrass silage showed a fast and large pH decrease caused by a fast and large production of lactic acid during the first 5 days of ensiling and succeeded to achieve lactic acid type fermentation; high lactic acid/acetic acid and lactic acid content at the end of ensiling (14 days), low values of pH (3.74), acetic acid, ethanol and ammonia-N/total nitrogen, none or only small amounts of Butyric acid, valeric acid and propionic acid. The guineagrass silage showed a slow decrease in pH and a slow increase in lactic acid content during the full ensiling period, causing a high final pH value, low contents of lactic acid, acetic acid, total volatile fatty acids and total organic acids. In Italian ryegrass silage, mono- and di-saccharides compositions decreased largely within the initial 0.5 day (12 h) of ensiling. Sucrose disappeared rapidly within the initial 0.5 day of ensiling, but fructose and glucose contents showed an initial rise by the activity of enzymes in plant tissues, and then decreased gradually. On the other hand, the contents of monoand di-saccharides in guineagrass showed the largest decreases due mainly to plant respiration within the initial 0.5 day of ensiling, and no initial rises in fructose and glucose contents during the early stage of ensiling because of the absence of fructans which are hydrolyzed into fructose and glucose in temperate grasses. In both silages, the rate of reduction in mono- and di-saccharides compositions within the initial 5 days of ensiling was ranked in the order of glucose>fructose>sucrose, suggesting that glucose and fructose might be more favorably utilized than sucrose by microorganisms and glucose is the first fermentation substrate. It was concluded that the silage made from Italian ryegrass with high moisture content had a good fermentation quality owing to the dominance of lactic acid bacteria and active lactic acid fermentation during the initial stage of ensiling. These results can be explained by rapid plant sap liberation and the high activity of plant enzyme hydrolyzed fructans into fructose and glucose within the initial 2 days of ensiling, which stimulate the homofermentative lactic acid bacteria growth. In ensiling a temperate grass, the physical characteristics may ensure the rapid onset of fermentation phase, which results from the smaller losses of water-soluble carbohydrates during the initial stage of ensiling and providing sufficient water-soluble carbohydrates for lactic acid bacteria. The silage made from guineagrass with intermediate dry matter and high initial mono- and di-saccharides content was stable silage. This could be explained by the higher incorporation of air during the very early stage of ensiling and the restriction of cell breakdown and juice release due to the properties of a tropical grass with coarse porosity and stemmy structures. These physical characteristics delayed the onset of lactic acid bacteria fermentation phase by extending the phases of respiration and aerobic microorganisms activity, causing the higher loss of water-soluble carbohydrates and the shortage of lactic acid bacteria fermentation substrates.

• Journal of Food Hygiene and Safety
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• v.35 no.5
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• pp.459-467
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• 2020

In this study, we investigated the changes in both ambient temperature and microbial contamination of fresh convenience foods (FCFs) caused by the behavior of consumers after purchase. According to consumer survey results, it took 0.5 to 3 h put the purchased FCF in a home refrigerator or consume it. Only aerobic bacteria and Staphylococcus aureus (below maximum permitted limit) were detected in FCFs obtained from a local market. During storage of FCFs in a vehicle trunk for up to 3 h. the external and internal temperatures of FCFs were found to be 19 and 18.5℃ in spring, 44 and 42℃ in summer, 31.3 and 29.2℃ in autumn, and 17.6 and 16.8℃ in winter, respectively. Changes in contamination levels of aerobic bacteria on FCFs stored in a vehicle trunk for up to 3 hours are as follows: 2.72 → 3.41 log CFU/g in spring, 3.11 → 4.32 log CFU/g in summer, 3.08 → 3.81 log CFU/g in autumn, 2.71 → 3.36 log CFU/g in winter. S. aureus exceeding the tolerance was detected even when the FCFs were stored in a vehicle trunk for 1 h in summer and autumn and 2 h in spring and winter. Among three boxes (corrugated box, styrofoam box, and corrugated box coated with an aluminum film), the styrofoam box maintained the lowest temperature and showed the lowest growth rate of microorganisms on FCF after storage for 3 h in the vehicle trunk depending on whether ice was added. These results indicated that the possibility of food poisoning occurs when FCFs are exposed to the external environment. It is necessary to provide guidelines regarding storage temperature and allowable time for safe consumption of FCFs after purchase.

• Journal of the Korean Applied Science and Technology
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• v.31 no.1
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• pp.31-43
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• 2014

This experiment evaluated the interaction effect of extreme heat diet(EHD), inverse lighting, and cool water on the growth performance of broiler chickens under extreme heat stress. There were 4 experimental groups (T1: EHD 1, 10:00-19:00 dark, 19:00-10:00 light, cold water $9^{\circ}C$; T2: EHD 2, 10:00-19:00 dark, 19:00-10:00 light, cold water $9^{\circ}C$; T3: EHD 1, 09:00-18:00 dark, 18:00-09:00 light, cold water $14^{\circ}C$; T4: EHD 2, 09:00-18:00 dark, 18:00-09:00 light, cold water $14^{\circ}C$), each group composed of 25 broilers and the experiment was repeated 3 times. EHD 1 contained soybean oil, molasses, methionine and lysine. EHD 2 contained all nutrients of EHD 1 and vitamin C additionally. As a result, T1 and T2 displayed higher body weight increase and diet intake compared to T3 and T4 (p<0.05). The weights of their liver and gizzard were similar but the weights of the thymus and bursa F were higher for T1 and T2 compared to that of T3 and T4 (p<0.05). It was observed that T1 and T2 displayed higher concentrations of blood triglyceride, total cholesterol, HDL-C and blood sugar compared to that of T3 and T4 but LDL-C level was higher for T3 and T4 compared to that of T1 and T2 (p<0.05). T1 and T2 displayed higher levels of immunity substances such as IgG, IgA and IgM compared to T3 and T4 but the blood level of corticosterone displayed to be lower for T1 and T2 compared to T3 and T4 (p<0.05). The T1 and T2 contained a higher amount of fecal lactobacillus compared to that of T3 and T4 but the T3 and T4 contained a higher amount of fecal E. coli, total aerobic bacteria, coliform bacteria compared to that of T1 and T2 (p<0.05). T1 and T2 displayed higher concentrations of cecal acetic acid, propionic acid and total short chain fatty acids compared to T3 and T4 but T3 and T4 displayed higher concentrations of butyric acid, isobutyric acid, valeric acid and isovaleric acid compared to T1 and T2 (p<0.05). These results have been observed that broiler chickens exposed to extreme heat stress with feeding EHD, inverse lighting and cold water would improve blood lipid, and elevate the production of immunity substance, beneficial microorganisms, and short chain fatty acids. This provision would also reduce the blood sugar consumption rate as energy sources and these effects will improve the growth performance of the broilers exposed to extreme heat.

• The Korean Journal of Mycology
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• v.24 no.1 s.76
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• pp.38-48
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• 1996

The survival or colonization of beneficial organsisms and suppression of root rot of ginseng (Panax ginseng) by two distinct bacteria, Pseudomonas cepacia, Bacillus cereus and three mycorrhiza in pot soil were investigated and compared with uninoculated root. In separate inoculation, colonization of roots by P. cepacia was maintained at 6.25 (log cfu/g root) during growth for 10 days under pot culture conditions comparing to $5.62{\sim}6.19$ by mixed treatment with other organisms. Colonizations of P. cepacia were gradually decreased from 6.25 (log cfu/g root) in 10 days growth to 3.01 (log cfu/g root) in 270 days incubation period. This reduction was also investgated in combination treatments by B. cereus or F. solani. The numbers of Fusarium spp. were colonized high number in rhizosphere soil from 3.33 to 3.67 (log cfu/g root) in control within $10{\sim}60$days after treatment of pathogen F. solani, but it's numbers were markedly decreased in 270 days cultivation of plant from 3.33 to 1.02 (log cfu/g root) after treatment. In treatment of beneficial strains of P. cepacia and B. cereus, P. cepacia significantly suppressed the development of root rot from 4.3 in control to 1.2 in treatment, whereas B. cereus alone had no effect on the rate of disease suppression. The disease index $(1.8{\sim}2.3)$ in combination of two bacteria was reduced in plants inoculated with both P. cepacia and B. cereus comparing to the index (4.3) of control. As an effect of inoculation with mycorrhiza on disease suppression, suppression of root rot by F. solani was reduced to $1.2{\sim}1.6$ in disease index in treatment of Glomus albidum and Acaulospora longular comparing to 4.3 of control. In the treatment of bacterial strain P. cepacia and mycorrhizal fungus Glomus albidum, the disease suppression was apparent to 1.2 and 1.2 comparing to 4.3 of control in disease index respectively.

• Journal of Animal Science and Technology
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• v.47 no.6
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• pp.985-1000
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• 2005

In vitro anaerobic incubations of timothy (Phleum pretense L.) forage with bovine rumen fluid were conducted at 39℃ for 0, 3, 6, 9, 24, and 36 h in three trials to examine the biohy- drogenation of linolenic (C18:3) and linoleic acids (C18:2) and their bypass from the rumen. The objectives of the first trial was to study the effect of growth stage (stem elongation, early heading, late heading, and early flowering) and N-fertilization (0 and 120 kg N ha－1) on in vitro biohydrogenation of C18:2 and C18:3. The hydrogenable fraction, the effective disappearance and the bypass of C18:2 and C18:3 were high in timothy harvested at stem elongation, and decr- ease linearly with maturity. The N-fertilization increased the hydrogenable fraction of C18:3, the effective disappearance and the bypass of C18:2 and C18:3. However, the rate of disappearance of C18:2 and C18:3 were not affected by maturity and N-fertilization (P>0.1). In trial 2, the effect of timothy conservation method on in vitro C18:2 and C18:3 biohydrogenation was determined. Silage had the highest effective disappearance of C18:2 and C18:3, and grass hay had lowest one. The amounts of C18:2 and C18:3 biohydrogenated were higher in haylage and silage than in grass hay. Comparative to haylage timothy, the bypass of C18:3 was higher in fresh grass, wilted grass and grass hay. The bypass of C18:2 was higher in fresh grass and silage in comparison to grass hay and haylage. In trial 3, the effects of formic acid and Lactobacillus plantarum inoculum addition to timothy haylage and silage on C18:2 and C18:3 disappearance and bypass were studied. Haylage and silage additives had no effect (P>0.1) on effective disappearance and bypass of C18:2 and C18:3. The addition of formic acid increased the rate of biohydrogenation of C18:3 in haylage and silage, but it decreased the hydrogenable fraction of C18:2 in silage. The results of these three incubation trials show that the hydrogenable fraction and the bypass of C18:2 and C18:3 in timothy decreased with maturity and increased with N-fertilization. Higher amount of C18:2 and C18:3 were biohydrogenated in haylage and silage than in grass hay, and C18:3 ruminal disappearance was higher in fresh grass, wilted grass and grass hay than in haylage.