• Horticultural Science & Technology
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• v.32 no.3
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• pp.318-329
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• 2014

In order to gain insight into the physiological responses of plants to high temperature stress, the effects of temperature on Chinese cabbage (Brassica campestris subsp. napus var. pekinensis cv. Detong) were investigated through analyses of photosynthesis and chlorophyll fluorescence under 3 different temperatures in the temperature gradient tunnel. Growth (leaf length and number of leaves) during the rosette stage was greater at ambient $+4^{\circ}C$ and ambient $+7^{\circ}C$ temperatures than at ambient temperature. Photosynthetic $CO_2$ fixation rates of Chinese cabbage grown under the different temperatures did not differ significantly. However, dark respiration rate was significantly higher in the cabbage that developed under ambient temperature relative to elevated temperature. Furthermore, elevated growth temperature increased transpiration rate and stomatal conductance resulting in an overall decrease of water use efficiency. The chlorophyll a fluorescence transient was also considerably affected by high temperature stress; the fluorescence yield $F_J$, $F_I$, and $F_P$ decreased considerably at ambient $+4^{\circ}C$ and ambient $+7^{\circ}C$ temperatures, with induction of $F_K$ and decrease of $F_V/F_O$. The values of RC/CS, ABS/CS, TRo/CS, and ETo/CS decreased considerably, while DIo/CS increased with increased growth temperature. The symptoms of soft-rot disease were observed in the inner part of the cabbage heads after 7, 9, and/or 10 weeks of cultivation at ambient $+4^{\circ}C$ and ambient $+7^{\circ}C$ temperatures, but not in the cabbage heads growing at ambient temperature. These results show that Chinese cabbage could be negatively affected by high temperature under a future climate change scenario. Therefore, to maintain the high productivity and quality of Chinese cabbage, it may be necessary to develop new high temperature tolerant cultivars or to markedly improve cropping systems. In addition, it would be possible to use the non-invasive fluorescence parameters $F_O$, $F_V/F_M$, and $F_V/F_O$, as well as $F_K$, $M_O$, $S_M$, RC/CS, ETo/CS, $PI_{abs}$, and $SFI_{abs}$ (which were selected in this study), to quantitatively determine the physiological status of plants in response to high temperature stresses.

• Korean Journal of Food Science and Technology
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• v.21 no.6
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• pp.788-794
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• 1989

This study was attempted to investigate the effects of blanching temperature and cooking methods on the changes in the proportions of vitamin C of fresh potato and potatoes with different storage time. Sensory evaluation of fresh potato by different cooking methods was also conducted. The contents of residual ascorbic acid(AA) and total ascorbic acid(TAA) of fresh potato were maximum at $40^{\circ}C$ followed by rapid decrease at $50-65^{\circ}C$ while leached AA and TAA showed steady increase as the blanching temperature increased. Oxidized AA and dehydroascorbic acid(DHA) hydrolyzed increased at $50-65^{\circ}C$. From these results, it was considered that AA was lost mainly by oxidation up to $65^{\circ}C$ and leaching of AA was the major mode of loss above $65^{\circ}C$. In the case of potatoes stored for 1-4 weeks, they showed similar changes in the proportions of vitamin C as that of fresh potato. However, at $40^{\circ}C$ the content of residual TAA decreased and those of leached TAA and DHA hydrolyzed increased redundant during storage. At $65^{\circ}C$, the content of DHA hydrolyzed decreased The residual TAA of fresh potato by different cooking methods decreased in the order of pressure cooking (PC) > microwave cooking (MC)>boiling. Leached TAA were 49.5% and 36.4%, during boiling and MC, respectively. While DHA hydrolyzed were 22.3% and 4.2%, respectively Leached TAA and DHA hydrolyzed during PC were not determined. From these results, it was considered that AA was lost mainly by leaching during cooking. Residual TAA of stored potatoes by different cooking methods decreased during storage. But leached TAA and DHA hydrolyzed did not show any steady increase or decrease. Overall eating quality of fresh potato by different cooking methods decreased in the order of PC>MC>boiling(p<0.05).

• Korean Journal of Food Science and Technology
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• v.44 no.2
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• pp.207-215
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• 2012

Six different mashing types ((A) $koji$+purified enzyme, (B) $koji$+crude enzyme, (C) $koji$+$nuruk$, (D) $koji$+purified enzyme+$nuruk$, (E) $koji$+crude enzyme+$nuruk$, (F) purified enzyme+$nuruk$) had been established, according to fermentation agents and a mixing rate of rice $makgeolli$, in this study. The alcohol content was the highest in the mashing type (C), which was 13.6%, followed by (D) 13.5%, (A) 13.1%, (B) 12.9%, (E) 12.7% and (F) 12.1%. The reducing sugar content of (A) was the highest with 401.6 mg% and those of (B), (C), (D) and (F) were between 337.3- 380.9 mg%. The alcohol components were found and tended to increase during the fermentation. The oligo-saccharides content was the highest in (D) with 1251.3 mg%, which was followed by (E) 1,219.2 mg%, (C) 1,141.4 mg%, (A) 1,049.9 mg% and 973.8 mg% in (B). The total free amino acid was highest in (B) with 781.4 mg% and followed by (C) 703.2 mg%, (D) 702.6 mg%, (E) 678.7 mg%, (A) 630.4 mg% and (F) 328.7 mg% in order. There were 16 different types of volatile flavor components, in the mashing types (A) and (B), in addition to 15 different types of those in type (C), as well as 14 different types of those in (D), (E) and (F). There were significant differences in the overall preference between the type (A) and (C).

• Korean Journal of Food Science and Technology
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• v.42 no.1
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• pp.75-81
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• 2010

In order to investigate the effects of different milling degrees on the quality of glutinous rice wines, the physicochemical properties and volatile compounds of various wines were evaluated. Sample wines prepared from glutinous rice with 90, 80, and 70% milling yields were analyzed for ethanol, pH, total acids, amino acids, soluble solids, coloring degree, UV absorbance, reducing sugars, organic acids, free sugars and volatile compounds. After fermentation for 17 days, ethanol contents in the wines ranged from 15.2 to 15.85%, while total acid levels ranged from 0.31 to 0.35%. The amino acid contents in four samples ranged from 0.63 to 0.73%, while soluble solid contents ranged from 11.4 to $13.1^{\circ}Bx$. The wine prepared from glutinous rice with a 30% degree of milling showed the highest coloring degree, UV absorbance and reducing sugar content among four samples. Furthermore, this wine had the highest levels of malic acid and acetic acid, while the glutinous rice wine prepared from rice with a 0% degree of milling had the highest levels of succinic acid and lactic acid. In all the glutinous rice wines tested, the most abundant free sugar was glucose followed by maltose. With increasing degree of milling, the alcohol, amino acid and organic acid contents of the glutinous rice wines decreased, whereas soluble solids, coloring degree, UV absorbance, reducing sugar and free sugar contents increased. Volatile compounds were identified using GC-MSD, and thirty-nine esters, seven alcohols, six acids, one aldehyde, four alkanes, one alkene and two miscellaneous compounds were identified in the glutinous rice wines. Using relative peak area, it was determined that other than ethyl alcohol, hexadecanoic acid ethyl ester was the major component and was primarily found in the range of 11.566-18.437%. Succinic acid diethyl ester and isoamyl laurate decreased with an increasing degree of milling, whereas hexanoic acid ethyl ester and 2-octenoic acid ethyl ester increased. Overall, it was shown that different milling degrees greatly affected the physicochemical and volatile characteristics of the glutinous rice wines.

• Journal of Animal Science and Technology
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• v.50 no.2
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• pp.255-264
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• 2008

The effects of hot air dried tomato powder on the physicochemical and sensory properties of meat patties were studied. The control(C, no addition) and 4 treatments with addition of hot air dried tomato powder(T1, 0.25; T2, 0.50; T3, 0.75; and T4, 1.00%) were prepared and stored for 7 days at 5℃. The pH values of T4 were significantly lower(p<0.05) than those of control and other treatments during initial storage, however, the pH values of T4 were higher(p<0.05) at 7 days of storage. The cooking loss was not significantly different between control and all treatments. The 2-thiobarbituric reactive substances (TBARS) of meat patties containing hot air dried tomato powder were significantly lower(p<0.05) compared to those for control during the whole storage. The volatile basic nitrogen(VBN) values of T2 increased(p<0.05) significantly as the storage period increased, but there was no difference in VBN between control and the other treatments(T1, T3, T4). In meat color, L*, a* and b* of meat patties containing hot air dried tomato powder showed slightly higher (p>0.05) than that of control. a* and b* of T4 were the highest(p<0.05) among the all products. Total plate counts(TPC) increased(p<0.05) significantly as the storage period increased. The result of TPC showed the range of 5.48(T2)~6.98(C) log CFU/g at the 7 day of storage. Sensory panels evaluated that pork patties containing hot air dried tomato powder had the slightly higher score in overall acceptability.

• Food Science of Animal Resources
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• v.26 no.2
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• pp.166-174
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• 2006

To determine the proper processing and storage conditions, physico-chemical, microbial and sensory properties of venison jerky under different dry times were measured during storage at $30^{\circ}C$ for 28 days. Samples were dried for 3 hr (T1), 4 hr (T2) and 5 hr (T3) at $75^{\circ}C$ in the smoke chamber, respectively. The pH of T1 was slightly lower than those of T2 and T3 as storage time increased. As dry and storage time increased, TBARS of T2 and T3 were significantly higher (p<0.05) than that of T1. In meat color, $L^*$ values of T3 showed slightly higher than those of T1 and T2, while at values were not clearly tendency by the passage of storage time. $b^*$ values of T2 and T3 were higher than that of T1. The water activity were significantly lower (p<0.05) in ,the order of T3$log_{10}$ CFU/g until 28 days and its number were accepted by sensory evaluation. In conclusions, T2 and T3 showed slightly high overall acceptability and lipid oxidative stability compared to T1 conditions. These results indicated that longer dry time ($4{\sim}5 hr$) of venison jerky would be better characteristics as compared to shorter dry time (3 hr) with increased storage time at $30^{\circ}C$.

• Journal of the Korean Society for Marine Environment & Energy
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• v.10 no.3
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• pp.138-147
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• 2007

An emergy concept was used to evaluate the environment and economy of the Han River basin in Korea and to suggest policy perspectives far the sustainable utilization of its environment and associated estuarine ecosystem. The economy of the basin used $5.19{\times}10^{23}\;sej/yr$ of emergy in 2005. The economy of the Han River basin was heavily dependent on outside energy sources from foreign countries and other parts of Korea, with internal sources, renewable and nonrenewable, contributing only 15.6% to the total emergy use. The basin's trade balance in terms of emergy showed trade surplus, whereas there was a deficit in monetary terms. The population of the Han River basin was far greater than the carrying capacity calculated using the emergy flow, with renewable carrying capacity only at 1.8% of the basin's population and developed carrying capacity at 14.3%. The economy of the basin imposed a substantial stress on its environment, with an environmental loading ratio of 54.8. Overall, the economy of the Han River basin was not sustainable with an emergy sustainability of 0.02. These are reflected in lower quality of living expressed in the emergy term than the national average. Deconcentration of population and economic activities is needed to reduce environmental stress on the environment of the basin and its valuable estuarine ecosystem. Policies to restore ecosystem productivity of the basin are also needed to ensure the sustainability of the basin's economic activities and the sustainable utilization of the Han River estuary. In this regard, it is urgently needed for the Korean government to implement sustainable management measures for the Han River estuary, a well-preserved, productive natural estuarine ecosystem in Korea.

• Korean Journal of Ecology and Environment
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• v.39 no.4 s.118
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• pp.498-507
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• 2006

The main objective of present study was to evaluate how seasonal rainfall influenced natural habitat conditions of 10 metric habitat variables along with ionic conditions and suspended solids in the Woopo Wetland during August 2002-July 2003. Largest spatial variabilities in total suspended solids (TSS) occurred during the summer monsoon and the inorganic suspended solids (ISS), expressed as a inorganic proportion of total solids, showed linearly increasing trend from the upstream to downstream. This phenomenon was mainly attributed to counter flow of turbid water from the main Nakdong-River. During the flooding, ISS : TSS ratio showed large increases (92%) in the downstream than the upstream (43%). For this reason, transparency declined (mean=0.13 m, range=0.08-0.21 m) largely in the downstream reach and thus, chlorophyll-a concentration showed low values (range: $4.2-8.6\;{\mu}g\;L^{-1}$), indicating a direct influence on primary productivity or algal growth by inorganic turbidity. In the 2nd survey, ISS averaged 4.0 mg $L^{-1}$ (3.3-4.8 mg $L^{-1}$), thus the ISS decreased by 14 fold, compared to the ISS in the 1st survey during the flooding, while organic suspended solids (OSS) values were greater than those of ISS, indicating a dominance of organic solids. This condition was similar to solid contents in the 3rd survey, but showed a large difference compared to the 4th survey during the growing season. Habitat health assessments, based on 10 metric habitat variables, showed that QHEI values were greatest in the growing season (May) than any other seasons and largest spatial variations occurred in the 2nd survey. Overall, dataset suggest that seasonal episodic flooding during the monsoon may largely contribute nutrient cycling and sediment contents in the Woopo Wetland and Topyung Stream.

• Korean Journal of Ecology and Environment
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• v.43 no.2
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• pp.307-318
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• 2010

This study was to analyze the ecological conditions, based on physical habitat, chemical, and biological conditions before (2006, 2007) and after ecological restoration (2009) in five sites of Changwon Stream (CS) and six sites of Nam Stream (NS), respectively, and then to compare ecological health between the two period. The analysis of ecological health was based on the multimetric models of Index of Biological Integrity (IBI) and Qualitative Habitat Evaluation Index (QHEI) along with water chemistry in the streams. For the study, the models of IBI and QHEI were modified as 8 and 11 metric attributes, respectively. For the evaluations, the survey was conducted in the period of 2006~2007 before the restoration and in 2009 after the restoration by the city. Chemical conditions, based on conductivity, in both streams showed a typical longitudinal declines along the axis of the upstream-to-downstream. There were no significant differences (p>0.05) in water quality between the two periods. Values of IBI in the CS and NS averaged 21.6 and 19.7, respectively, indicating a C grade in the criteria of Ministry of Environment, Korea, and there was no significant differences in the IBI between the two periods. Values of QHEI after the restoration averaged 29.2 and 63.2 in the CS and NS, respectively and the values decreased markedly especially, in the NS (35.3) after the restoration. The habitat disturbance was mainly attributed to destructions (i.e., the narrower width of riparian vegetation and higher substrate exposure by the air) of artificial materials by massive flood in 2009. Overall, our results suggest that the restoration was not effective in the two streams between the two periods, even if the budget was used a lot and that such ecological restoration, not considered the natural disaster, may not effect for the stream restoration.

• Tuberculosis and Respiratory Diseases
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• v.59 no.5
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• pp.504-509
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• 2005

Background : Endobronchial tumors cause life-threatening dyspnea and can lower the quality of life due to central airway obstruction. In those cases with an intraluminal tumor, various bronchoscopic techniques are available for tumor debulking. The therapeutic effect of bronchoscopic electrocautery for palliation in patients with a symptomatic tumor obstruction was studied. Method : Nineteen patients with bronchogenic carcinomas (n=15) and metastatic tumors affecting the bronchi (n=4), between March 2002 and March 2005, were enrolled in this study. Electrocautery was performed under local anesthesia using an electroprobe and diathermic snare. Using flexible bronchoscopy, a follow-up bronchoscopic examination was performed 3-4 days later. Symptom improvement was evaluated by $FEV_1$, FVC and dyspnea score (Modified Borg Category Scale (0~10)), both before and after the electrocautery. Results : The success rate of electrocautery on the follow up examination was 84%. Patients with endoluminal airway lesions had a mean overall decrease in the size of the obstruction to $47.8{\pm}15.7%$. The mean Improvement in the dyspnea score immediately after the endobronchial tumor debulking was $2.78{\pm}1.42$. The average improvements in the $FEV_1$ and FVC after electrocautery were $0.32{\pm}0.19L$ and $0.5{\pm}0.22L$, respectively. There were 2 cases of complications related with electrocautery (one each of pneumothorax and pneumonia). Conclusion : Electrocautery using an electroprobe and diathermic snare was an effective and safe palliative treatment for a symptomatic endoluminal airway obstruction in lung cancer.