• Journal of the Korean Society of Food Science and Nutrition
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• v.43 no.8
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• pp.1217-1227
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• 2014

This study investigated the physicochemical properties and antioxidant activity of vinegar added with different levels (0%, 1%, 3%, 5%, and 7%) of Akebia quinata fruit during two-step fermentation. The physicochemical properties of vinegar evaluated were pH, total acidity, alcohol, and total sugar and amino acid contents. The antioxidant activities were based on ABTS radical scavenging activity, SOD-like activity, and reducing power. During alcohol fermentation, total acidity and alcohol contents of vinegar increased, but total sugar contents decreased. During acid fermentation, total acidities of vinegar increased. Vinegar added with 7% A. quinata fruit showed the highest total sensory score. Total polyphenol contents of vinegar added with 0% and 1% A. quinata fruit were not significantly different. However, vinegar added with 3, 5, and 7% A. quinata fruit showed significantly higher total polyphenol contents of 136.6, 381.59, and 415.35 mg/100 g, respectively, after 13 days of fermentation. Further, total flavonoid contents of vinegar added with 0~7% A. quinata fruit significantly increased to 21.73, 15.79, 15.15, 26.19, and 26.87 mg/100 g, respectively, after 13 days of fermentation. In addition, tannin contents of vinegar added with 0~7% A. quinata fruit significantly increased to 0.2042, 0.2004, 0.1255, 0.1384, and 0.1255 mg/100 g, respectively, after 13 days of fermentation. Moreover, ABTS radical scavenging activities of vinegar added with 0~7% A. quinata fruit significantly increased to 5.87, 12.59, 25.63, 34.02, and 35.25, respectively, after 13 days of fermentation at a concentration of 5 mg/mL. Additionally, SOD-like activities of vinegar added with 0~7% A. quinata fruit significantly increased to 8.22, 17.49, 16.86, 16.89, and 15.68%, respectively, after 13 days of fermentation. Reducing power of 7% A. quinata fruit was 0.527 after 1 day and 1.539 at the end of fermentation. Our results demonstrate that antioxidant activity significantly increased during fermentation according to the content of A. quinata. Further, the total polyphenol, flavonoid, and tannin contents were shown to be closely related with antioxidant activities. Thus, A. quinata could be effectively used as a vinegar and functional food material based on its antioxidant activity.

• Journal of the Korean Society of Food Science and Nutrition
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• v.46 no.4
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• pp.459-464
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• 2017

Biphenyl is used as an intermediate in the production of crop protection products, a solvent in pharmaceutical production, and as a component in the preservation of citrus fruits in many countries. Biphenyl is not authorized for use and also does not have standards or specifications as a food additive in Korea. National and imported food products are likely to contain biphenyl. Therefore, control and management of these products is required. In this study, a simple analytical method was developed and validated using HPLC to determine biphenyl in food. These methods are validated by assessing certain performance parameters: linearity, accuracy, precision, recovery, limit of detection (LOD), and limit of quantitation (LOQ). The calibration curve was obtained from 1.0 to $100.0{\mu}g/mL$ with satisfactory relative standard deviations (RSD) of 0.999 in the representative sample (orange). In the measurement of quality control (QC) samples, accuracy was in the range of 95.8~104.0% within normal values. The inter-day and inter-day precision values were less than 2.4% RSD in the measurement of QC samples. Recoveries of biphenyl from spiked orange samples ranged from 92.7 to 99.4% with RSD between 0.7 and 1.7% at levels of 10, 50, and $100{\mu}g/mL$. The LOD and LOQ were determined to be 0.04 and $0.13{\mu}g/mL$, respectively. These results show that the developed method is appropriate for biphenyl identification and can be used to examine the safety of citrus fruits and surface treatments containing biphenyl residues.

• Journal of the Korean Society of Food Science and Nutrition
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• v.46 no.4
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• pp.490-500
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• 2017

This study was performed to evaluate repeated dose oral toxicity upon administration of the test substance 1,2-benzisothiazolin-3-one for 90 days and to determine NOAEL (no observed adverse effect level) and target organs in Sprague-Dawley rats. Single, 2-week repeated, and 13-week repeated oral dose toxicity studies were conducted in Sprague-Dawley rats. The dose levels of groups were 1,250, 2,500, and 5,000 mg/kg/d. All dose groups were compared with the vehicle control group. The animals were observed for clinical signs and weekly body weight. Urinalysis, hematology, and serum biochemistry analyses were conducted. Subsequently, animals were sacrificed and subjected to histopathological examination. For the result, NOAEL of ethanol extract from unripe fruit of bitter melon had an optimal dose of 5,000 mg/kg/d and acceptable daily intake up to 3,000 mg/man. There was no target organ detected. Therefore, bitter melon, which contains a variety of bioactive substances, could be widely used as a health functional food ingredient.

• Journal of the Korean Society of Food Science and Nutrition
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• v.46 no.10
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• pp.1164-1170
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• 2017

Protaetia brevitarsis larvae (PBL) has recently been registered as a temporary food in Korea, and this study evaluated the application potential of PBL proteins as health functional food materials. Protein hydrolysates were prepared from PBL powder by enzymatic hydrolysis using five different proteases (alcalase, bromelain, flavourzyme, neutrase, and papain), and based on the results from the peptide content and SDS-PAGE analyses, PBL treated with alcalase or flavourzyme showed a high degree of hydrolysis (HD) value, whereas the HD value of those treated with neutrase, bromelain, or papain was minimal. The protein hydrolysates showing a high HD value were separated further into the fractions of >3 kDa and <3 kDa by a centrifugal filter system and then lyophilized, and according to the $RC_{50}$ values of the protein hydrolysates (<3 kDa) obtained from three different antioxidant analyses; the alcalase hydrolysates showed the highest antioxidant activity. Therefore, the alcalase hydrolysates were tested further for their inhibitory effects on the peroxidation of linoleic acid by measuring the thiobarbituric acid values. The results showed that the peroxidation of untreated linoleic acid increased dramatically during 6 days of incubation, but a pretreatment with the hydrolysates ($100{\sim}800{\mu}g/mL$) significantly inhibited the linoleic acid peroxidation in a dose-dependent manner for 6 days. Our current studies are focused on the identification of active peptide sequences from alcalase hydrolysates.

• Journal of the korean academy of Pediatric Dentistry
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• v.41 no.3
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• pp.207-217
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• 2014

The purpose of the present study was to evaluate the relationship between the malocclusion and dental caries in adolescents with permanent dentition. The subjects of the study were 385 adolescents aged 12 to 15 years. Dental Aesthetic Index (DAI) and DMFT index were recorded as clinical indicators of malocclusion and dental caries. The mean Dental Aesthetic Index (DAI) score of the subjects was 12.42 and the mean DMFT index of the subjects was 2.89. Four students (1.04%) were included in the group of orthodontic treatment mandatory, which signifies the handicapping malocclusion. Moreover, the result of gender-specific analysis of the DAI components observed that the prevalence of midline diastema and mandibular overjet were significantly higher among boys (p < 0.05). In 7 components (missing teeth, incisal segment crowding, maxillary anterior irregularity, mandibular anterior irregularity, mandibular overjet, anterior openbite, antero-posterior molar relationship) among the 10 DAI components, abnormal groups showed significantly higher DMFT index than normal groups (p < 0.05). The subjects in the group of definite to handicapping malocclusion (DAI ${\geq}$ 26) showed significantly higher DMFT index than the subjects in the group of minor or no malocclusion (p < 0.01). In addition, the DAI score had significant positive linear correlation with the DMFT index (r = 0.584, p < 0.01). Consequently, the current findings suggested a positive relationship between the malocclusion and caries prevalence. And several specific types of malocclusion were supposed to be significantly correlated with dental caries.

• Journal of The Korean Association For Science Education
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• v.18 no.4
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• pp.493-502
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• 1998

Science curricula of public and government institution schools from 1895 to 1910 in Korea were studied And through tracing people in charge of science education actual status was researched. The result of the study showed that 'physics, chemistry, nature' in the regular course for normal schools and 'department of science' in the short course were used for in the curriculum. Subject of nature were educated by SaitoKinji. 'Science' was educated by MatsumotoSoji in Department of Japanese Language at Foreign Language School and 'science of nature' by Hase in Department of German Language. 'Nature' and 'physics and chemistry' were taught by ShideharaTahira at Hansung Middle School which was established in 1899. MoriTamejo was in charge of subject of nature at Hansung High School which was a new name since 1906. It was also revealed that'physics and chemistry'were taught at Industrial Professional Institute. In short during the era of Taihan (Korea) Empire science education at public and government institution schools were entirely performed by Japanese. Furthermore the first time when professionals majored in natural science began to assume responsibility for science education was during late part of Taihan Empire and before that time tradition of science education was maintained by'non-professionals'like ShideharaTahira.

• Journal of The Korean Association For Science Education
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• v.23 no.5
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• pp.544-560
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• 2003

The purposes of this study were (1) to investigate the characteristics of the exhibits at three representative science centers or museums in Seoul, and (2) to analyse students' perceptions about the most and the least favorite exhibits selected by students as visitors. Three science centers investigated were Seoul National Science Museum, Seoul Education & Science Research Institute, LG Science Hall. The subjects for students' perception survey were 290 middle school students who visited the three science centers. The investigation of the exhibits showed that the goals, the contents, the visitors' viewing and manipulating activity types, and the explanation types of the exhibits depended on the purposes and the target visitors of each science center. Students' responses indicated that they most favored hands-on exhibit. And students preferred the exhibits that had new and comprehensible contents and the were related to what they had learned in school. Students said that they felt that science was exciting and that they came to experience what they did not do in school. Students said that reading or hearing given explanations was helpful to understand the exhibits, but about 20% of the students responded that they did not read explanation on panels at all. Students also said that guide's oral explanations were more understandable than written explanations on panels. Some of the students commented that having to wait for access because of crowds or because of the resetting time required for hands-on activities was inconvenience.

• Sleep Medicine and Psychophysiology
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• v.14 no.1
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• pp.33-41
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• 2007

Objectives: It has been known that the contents of dreams change according to neuro-developmental differences in sex, progression of age and various environments, unlike the established psychoanalytic theory. To investigate the changes, we collected "most recent dream report" and analyzed the contents of dreams by using Hall/Van de Castle System. Method: Most recent dream reports were gathered from age 12-14 years old, 2,673 middle school students (1,544 male 1,129 female) and analyzed those reports using Hall/Van de Castle System. The data were sorted in SAS and dream SAT. Result: There were prominent differences between male and female middle school students in Male/Female Percentage (male/ female；56%/35%), Familiarity Percentage (57%/69%), Aggression/Friendliness Percentage (79%/65%), Befriender Percentage (50%/33%), Physical Aggression Percentage (90%/70%), Indoor Setting Percentage (40%/55%), Negative Emotion Percentage (56%/68%) and Torso/Anatomy Percentage (51%/36%). There were significant differences in Male/Female Percentage (65%/44%), Friendliness, Physical Aggression and Self Negativity Percentage in male and there were significant differences in Friendliness, Familiarity and Friends Percent in female between 1st and 2nd grade. But, it showed much similar dream patterns between 2nd and 3rd grade in both gender. In male, Aggression/Character Index with male character is significantly increased by 2nd grade (1st/ 2nd/ 3rd；0.48/ 1.04/0.98), In female, Friendliness/Character Index with male character had significantly decreased by 2nd grade (0.38/ 0.19/0.20). Conclusion: There were apparent differences between age 12-14 years old male and female. Male adolescents have differences mostly in categories related with aggression, but female adolescents have differences in categories related with environment or character. It shows that developmental level of male are slower than female as of yet and male needs more active interpersonal relationship to find identity. Otherwise, the influences of passive attitude and actual circumferential environment are reflected in female's dream. There are no prominent differences among ages, but age 12-13 years old adolescents shows significant differences in interacting with the other gender. It means that circumferential environment and interpersonal relationship affect the contents of dreams and also the cognitive development related to age and sex. Afterwards, the development of dreams could be better understood through the neurocognitive study and dream analysis between other ages and nations.

• Tuberculosis and Respiratory Diseases
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• v.45 no.4
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• pp.766-775
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• 1998

Background : The prognosis of patients with lung cancer is still poor. Lung cancer exhibits a variable clinical outcome, even in those patients with same stage. Numerous reports suggest that oncogene expression might playa role in explaining the variability of response and survival But many of these reports are still under debate. So we studied the clinical relevance of oncogene expression in Korean lung cancer patients. Immunohistochemistry of p53, erbB-2, CEA expression was performed. Method: From March, 1992 until March, 1997, 120 patients with lung cancer were reviewed. p53, erbB-2, and CEA expression were detected on paraffin-embedded tumor blocks with the use of monoclonal antibodies. The survival and response has correlated with the expressibility of p53, erbB-2, and CEA oncoprotein Results: Overall, the expression rates of p53, erbB-2, and CEA were 33.7%, 59.3%, and 32.6% respectively. Expression rates were not correlated to cell type or stage. Compared with response to chemotherapy, no correlation was found. The expression of p53, erbB-2, or CEA was not correlated with 2-year survival. With simultaneous applications of p53, erbB-2, and CEA, patients with 2 or more expressions also did not show poor response to chemotherapy. Conclusion: We conclude the p53, erbB-2, and CEA expression are clinically less useful in predicting response to chemotherapy or survival.

• Journal of the Korean Society of Food Science and Nutrition
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• v.34 no.7
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• pp.959-967
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• 2005

Lead is a ubiquitous environmental and industrial pollutant that causes a major health concerns. It is known to induce a broad range of physiological, biochemical, and behavioral dysfunctions in laboratory and humans, including hematopoietic system, kidneys, liver, and reproductive system. This study was conducted to investigate the effect of Saengshik supplementation on the lead-induced toxicity in rats. Five week old male Sprague­Dawley rats were randomly assigned to five groups for six weeks as followings: control group (CT), lead acetate treated group (PT), and lead acetate groups administered with three different dosages of Saengshik $(SI2.5-12.5\%,\;S25-25\%,\;and\;S50-50\%).$ Lead acetate (12 mg/rat) was intragastrically administered daily for 6 weeks. The results were summarized as follows; Weight gain and food efficiency ratio were significantly lower (p<0.05) in lead administered group compared with those of the control group. Also, significant lead-induced alteration in blood hemoglobin (HGB), hematocrit (HCT), mean corpuscular volume (MCV), mean corpuscular hemoglobin (MCH), and reticulocyte distribution width (RDW) were observed. In the liver of lead-exposed animals, there was an increase in the lipid peroxidation (MDA) and the level of glutathione (GSH), but superoxiede dismutase (SOD) activity did not change. Lead-exposed animals with $25\%\;and\;50\%$ Saengshik supplementation showed marked improvements in the values of MCH, MCV, and RDW. Also, the level of HCT was significantly increased by $50\%$ Saengshik supplementation. The levels of liver MDA in $12.5\%\;and\;50\%$ Saengshik administered groups and GSH level in $50\%$ Saengshik administered group were significantly decreased compared to the lead administered group. Also, hepatic SOD activity tended to increase in the presence of Saengshik supplementation. Furthermore, the accumulation of lead in liver and kidney was reduced by presence of Saneghshik supplementation. Liver lead concentration was significantly reduced by both $25\%\;and\;50\%$ Saengshik supplementations and kidney lead concentration was significantly reduced by the $25\%$ Saengshik supplementation. These results show that Saengshik may have a protective effect against lead intoxication but the mechanism of their effects remains unclear.