• Korean Journal of Food Science and Technology
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• v.26 no.3
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• pp.317-323
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• 1994

Nine plant foods (persimmon leaf, perilla seed, Chinese quince, ginger root, walnut, mugwort leaf, arrowroot, buckwheat and sorghum) rich in phenolic substances were examined for their effects on the digestive enzymes, food-poisoning bacteria and mutagenicity/antimutagenicity by Ames test. Among tested samples, Chinese quince significantly inhibited the $\alpha-amylase$ activity (97%), exhibiting an uncompetitive inhibition type. Protease activity was inhibited by Chinese quince (86%), persimmon leaf (51%) and mugwort leaf (20%), in which mugwort extract exhibited a noncompetitive type. Lipase was activated >50% by all samples. The inhibition of $\alpha-amylase$ was highly correlated with the content of condensed tannin (r=0.89) and the inhibition of protease, with total phenolic content (r=0.84). Total phenolies fraction of tested samples showed the growth inhibition toward E. coli. Streptococcus faecalis and Salmonella enteritidis, in which the effect of perilla, sorghum and arrowroot was the highest for E. coli. Standard phenolics and food samples did not show any mutagenicity toward Salmonella typhimurium TA98 and TA100. Tannic acid inhibited the mutation of the two strains by benzo[a]pyrene whereas total phenolics fractions of Chinese quince and walnut exhibited antimutagenicity to a lesser extent.

• Journal of Korean Society of Forest Science
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• v.96 no.4
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• pp.455-461
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• 2007

This research was processed on morphological and physical characteristics of 'Yongdong' cultivar nuts. (1)Morphological properties of 'Yongdong' cultivar nuts were significantly different from the control, native species, in respect of all properties. (2) 'Yongdong' cultivar nuts showed higher figures than the native species on 9 items of morphological properties (kernel weight, size, length and width of pad on suture and etc.), whereas other 6 items (height of pad on suture, thickness of shell and septem, fragment numbers of isolated kernel, roundness index, and etc.) showed lower figures than those of the control. (3) In physical properties of the nut shells, 'Yongdong' cultivar was superior to the control at all items with the exception of compressive prove distance. Accordingly, it was also verified as effective cultivar of shelled walnut with suture line direction applied the minimum strength. (4) 'Yongdong' cultivar, 21.9 kg, was approximately twice lower than the control, 42.6 kg, on maximum compressive weight. It was demonstrated that the 'Yongdong' cultivar characterized by easily crushing shell by small strength was great in cracking properties. (5) On the study of yield strength, the native species being twice higher than 'Yongdong' cultivar showed the properties of the small elasticity and the shell hardness. While, the suture line of 'Yongdong' cultivar having the lowest yield strength 15.6 kg and 16.0 kg was identified the shell crushed easily. (6) The movement distance of the compressive prove of 'Yongdong' cultivar, 4.2 mm, was longer than that of the control, 2.7 mm. Subsequently, it means that the amount of loss possibly occurring to distribution process was not great, whereby productive value was high. (7) The compressive strength of the suture line of 'Yongdong' cultivar, $9.1kg/cm^2$, was much lower than total average of that $12.4kg/cm^2$. It was also statistically different with other properties. (8)The hardness examination by the compressive position revealed that the suture line of 'Yongdong' cultivar, $149.8kg/cm^2$, was lowest in contrast with the control, $300.9kg/cm^2$.

• Research in Plant Disease
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• v.29 no.4
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• pp.345-362
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• 2023

Anthracnose, caused by the Colletotrichum genus, comprises a significant number of plant pathogens and poses a major threat to fruit production worldwide, including South Korea. Colletotrichum species were identified associated with anthracnose in fruits such as apple, persimmon, plum, peach, jujube, walnut, and grape. A polyphasic approach, including morphology, multigene phylogenetics, and pathogenicity testing, was used. Additionally, the in-vitro sensitivity of identified Colletotrichum species to common fungicides was also evaluated. A total of nine Colletotrichum species within two complexes, namely gloeosporioides and acutatum, have been identified as the causal agents of anthracnose in common fruits in South Korea. In the gloeosporioides complex, we found Colletotrichumaenigma, C. fructicola, C. gloeosporioides, C. horii, C. siamense, and C. viniferum. Meanwhile, in the acutatum complex, C. fioriniae, C. nymphaeae, and C. orientalis were identified. Notably, C. fructicola, C. siamense, C. fioriniae, and C. nymphaeae were reported for the first time from apple, C. siamense, C. fioriniae and C. nymphaeae from plum, C. siamense, C. fructicola, and C. fioriniae frompeach, C. siamense and C. horii from persimmon, C. fioriniae from Omija (Schisandra), C. orientalis from walnut, C. nymphaeae from jujube, and C. aenigma, C. fructicola, and C. siamense fromgrape. Fungicide sensitivity tests revealed significant variation in the EC₅₀ values among specific Colletotrichum species when exposed to different fungicides. Moreover, the same Colletotrichum species isolated from different host plants displayed varying sensitivity to the same fungicide.

• The Journal of Korean Academy of Prosthodontics
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• v.47 no.2
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• pp.156-163
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• 2009

Statement of problem: Recently, there have been increased esthetic needs for posterior dental restorations. The failure of posterior dental ceramic restoration are possible not only by the characters of the component materials but also by the type of food. Purpose: The research aim was to compare the in vitro fracture resistance of simulated first molar crowns fabricated using 4 dental ceramic systems, full-porcelain-occlusal-surfaced PFG, half-porcelain-occlusal-surfaced PFG, Empress 2, Ice Zirkon and selected Korean foods. Material and methods: Eighty axisymmetric crowns of each system were fabricated to fit a preparation with 1.5- to 2.0-mm occlusal reduction. The center of the occlusal surface on each of 15 specimens per ceramic system was axially loaded to fracture in a Instron 4465, and the maximum load(N) was recorded. Afterwards, selected Korean foods specimens(boiled crab, boiled chicken with bone, boiled beef rib, dried squid, dried anchovy, round candy, walnut shell) were prepared. 15 specimens per each food were placed under the Instron and the maximum fracture loads for them were recorded. The 95% confidence intervals of the characteristic failure load were compared between dental ceramic systems and Korean foods. Afterwards, on the basis of previous results, 14Hz cyclic load was applied on the 4 systems of dental ceramic restorations in MTS. The reults were analyzed by analysis of variance and Post Hoc tests. Results: 95% confidence intervals for mean of fracture load 1. full porcelain occlusal surfaced PFG Crown: 2599.3 to 2809.1 N 2. half porcelain occlusal surfaced PFG Crown: 3689.4 to 3819.8 N 3. Ice Zirkon Crown: 1501.2 to 1867.9 N 4. Empress 2 Crown: 803.2 to 1188.5 N 5. boiled crab: 294.1 to 367.9 N 6. boiled chicken with bone: 357.1 to 408.6 N 7. boiled beef rib: 4077.7 to 4356.0 N 8. dried squid: 147.5 to 190.5 N 9. dried anchovy: 35.6 to 46.5 N 10. round candy: 1900.5 to 2615.8 N 11. walnut shell: 85.7 to 373.1 N under cyclic load(14Hz) in MTS, fracture load and masticatory cycles are: 1. full porcelain occlusal surfaced PFG Crown fractured at 95% confidence intervals of 4796.8-9321.2 cycles under 2224.8 N(round candy)load, no fracture under smaller loads. 2. half porcelain occlusal surfaced PFG Crown fractured at 95% confidence intervals of 881705.1-1143565.7 cycles under 2224.8 N(round candy). no fracture under smaller loads. 3. Ice Zirkon Crown fractured at 95% confidence intervlas of 979993.0-1145773.4 cycles under 382.9 N(boiled chicken with bone). no fracture under smaller loads. 4. Empress 2 Crown fractured at 95% confidence intervals of 564.1-954.7 cycles under 382.9 N(boiled chicken with bone). no fracture under smaller loads. Conclusion: There was a significant difference in fracture resistance between experimental groups. Under single load, Korean foods than can cause fracture to the dental ceramic restorations are boiled beef rib and round candy. Even if there is no fracture under single load, cyclic dynamic load can fracture dental posterior ceramic crowns. Experimental data with 14 Hz dynamic cyclic load are obtained as follows. 1. PFG crown(full porcelain occlusion) was failed after mean 0.03 years under fracture load for round candy(2224.8 N). 2. PFG crown(half porcelain occlusion) was failed after mean 4.1 years under fracture load for round candy(2224.8 N). 3. Ice Zirkon crown was failed after mean 4.3 years under fracture load for boiled chicken with bone(382.9 N). 4. Empress 2 crown was failed after mean 0.003 years under fracture load for boiled chicken with bone(382.9 N).

• Food Science and Preservation
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• v.21 no.6
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• pp.859-865
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• 2014

This study was conducted to analyze the hydrocarbons and 2-alkylcyclobutanones as marker compounds in walnuts after the walnuts' exposure to ${\gamma}$ irradiation. The samples were irradiated with gamma rays at 0, 1, 3, 5, 7, and 10 kGy doses. The lipids were extracted via soxhlet extraction using hexane, and were separated by florisil column and identified via gas chromatography / mass spectrometry (GC/MS). The hydrocarbons that were detected were 8-heptadecene ($C_{17:1}$) and 1,7-hexadecadiene ($C_{16:2}$) from oleic acid and 8,11-heptadecadiene ($C_{17:2}$) and 1,7,10-hexadecatriene ($C_{16:3}$) from linoleic acid. The 2-alkylcyclobutanones that were detected were 2-dodecylcyclobutanone (DCB) from palmitic acid, 2-tetradecylcyclobutanone (TCB) from stearic acid, 2-(5'-tetradecenyl)cyclobutanone (TECB) from oleic acid, and 2-(5',8'-tetradecadienyl)cyclobutanone (5',8'-TCB) from linoleic acid. The correlation between the irradiation dose and the concentrations of the hydrocarbons and 2-alkylcyclobutanones in the walnuts was found to be linear. The radio-induced hydrocarbons and 2-alkylcyclobutanones were clearly detected in the irradiated walnuts at 1 kGy and above, but not in the non-irradiated ones. The major hydrocarbons obtained after irradiation were 8-heptadecene from oleic acid and 8,11-heptadecadiene and 1,7,10-hexadecatriene from linoleic acid, and the major 2-alkylcyclobutanones were TECB from oleic acid and 5',8'-TCB from linoleic acid. Therefore, these major compounds were concluded to be the marker compounds for determining the irradiated and non-irradiated samples.

• Journal of Environmental Health Sciences
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• v.36 no.1
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• pp.52-60
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• 2010

High performance liquid chromatography (HPLC) and liquid chromatography mass spectrometry (LC/MS) have been widely used to quantify aflatoxins in food, but these methods are expensive, time-consuming, unsuitable for analysis of the routine screening of large sample numbers and require derivatization and high level techniques to perform. The objective of this study is to detect aflatoxins in a large number of foods by a high efficient analytical system of combined enzyme linked immunosorbent assay (ELISA) for screening and LC/MS/MS for confirmation. The samples spiked individually with aflatoxin $B_1$ (0.5 and 1.0 ng/g) and total aflatoxins (10 ng/g) were analyzed by ELISA and LC/MS/ MS, and the recoveries for ELISA and LC/MS/MS were 71.8~119.2% and 70.8~135.3%, respectively. A total of 378 samples (grains, nuts, soybean and fermented soybean foods, pepper and fermented pepper foods) were purchased from the six major cities in Korea and analyzed by ELISA-LC/MS/MS system. Twenty two (5.8%; peanut: 11, pistachio: 2, walnut: 6, almond: 1, pepper powder: 1, pepper paste: 1) out of 378 samples were screened as aflatoxin B1 positive by ELISA, but, 4 (1.1%; peanut: 2, pistachio:1, pepper powder: 1) out of the 22 samples screened were confirmed as aflatoxins positive at levels of 1.02~52.79 ng/g by LC/MS/MS. ELISA-LC/MS/MS system provides a more rapid, accurate and cost-effective method for the detection of aflatoxins in large number of samples.

• Korean Journal of Medicinal Crop Science
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• v.1 no.1
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• pp.63-69
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• 1993

Present experiment were attempted to examine in vitro multiplication throughbud culture of Cornus officinalis. Bud derived shoot formation was established successfully on Murashige and Skoog's medium supplemented with $0.5mg\;/\;{\ell}$ BAP(N-benzyl amino purine). The shoot proliferation increased on the Driver Kuniyuki Walnut medium containing $0.5mg\;/\;{\ell}$ NAA(Napthalene acetic acid) and $0.5mg\;/\;{\ell}$ BAP. Addition of 2,4-D(2,4-Dichlorophenoxy acetic acid) to the media produced excessive callus inducton. IAA(Indole-3-acetic acid) and IBA (Indole-3-bu-tyric acid) enhanced multple shooting, and NAA showed callus induction and multiple shooting. Shoot growth was enhanced supplemented with 3% sucrose, $2g\;/\;{\ell}$ activated charcoal, and 1 / 4MS in organic salts. However, root formation of proliferated shoots was low about 5%

• Journal of Korean Ophthalmic Optics Society
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• v.14 no.4
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• pp.33-37
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• 2009

Purpose: To examine the coloring condition of titanium spectacle frames with various colors by using anodization method. Methods: We made an anodization coater. Platinum plate with $3{\times}3cm^2$ was used for a cathode and titanium spectacle frame specimens was mounted on an anode in an electrolyte. An electric source device were designed to supply steady state current. The color of the coated spectacle frame specimens were measured by a spectrophotometer equipped with an integrating sphere. We use CIE $L^*a^*b$ color system as chromaticity coordinates. Results: The thickness of $TiO_2$ of titanium spectacle frame specimens was varied as controlling current flow time for electrodes. The specimens with various kinds of color as a walnut, a yellow brown, a navy blue, a blue, a light blue, a mung bean, a yellowish green, a light purple, a purple, a flower pink, a bluish green, an emerald, and a green color etc. were obtained. The values of CIE $L^*a^*b^*$ for these specimens were measured and analyzed to be changed clockwise in chromaticity coordinates as the thickness of $TiO_2$ increases. Conclusions: We identified the coloring mechanism by anodization method in titanium spectacle frame specimens.

• Clean Technology
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• v.23 no.1
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• pp.73-79
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• 2017

Recently usage of biomass is increased in pulverized coal power plants for reduction of $CO_2$ emission. Many problems arise when thermal share of the biomass is increased, and milling of the biomasses is one of the most important problems due to their low grindability when existing coal pulverizer is used. Grindability of coal can be measured through the HGI (Hardgrove grindability index) equipment as a standard, but method of measuring biomass grindability has not been established yet. In this study, grinding experiment of coal and biomass was performed using a lab-scale ball mill. One type of coal (Adaro coal) and six biomasses (wood pellet (WP), empty fruit bunch (EFB), palm kernel shell (PKS), walnut shell (WS), torrefied wood chip (TBC) and torrefied wood pellet (TWP)) were used in the experiment. Particle size distributions of the fuels were measured after being milled in various pulverization times. Pulverization characteristics were evaluated by portion of particles under the diameter of $75{\mu}m$. As a result, about 70% of the TBC and TWP were observed to be pulverized to sizes of under $75{\mu}m$, which implies that they can be used as alternative biomass fuels without modification of the existing mill. Other biomass was observed to have low grindability compared with torrefied biomass. Power consumption of the mill for various fuels was measured as well, and the results show that lower power was consumed for torrefied biomasses. This result can be used for characterization of biomass as an alternative fuel for pulverized coal power plants.

• Culinary science and hospitality research
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• v.22 no.7
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• pp.58-71
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• 2016

This study aimed to gauge the public awareness of the cultural value and superiority of Korean traditional sweets. Furthermore, it evaluated the obstacles that the Korean traditional sweet industry faces in the modern society, and a method to popularize it. It also analyzed the awareness of Korean traditional sweets. Both male and female study subjects showed the highest awareness of yakgwa and the lowest of chasugwa. Female respondents showed significantly (p<0.05~p<0.001) higher awareness of Osaekdasik, Hukimjadasik, Bellflower-junggwa, and Genseng-junggwa than male respondents. Maejakgwa, Osaekdasik, Rice-dasik, and Hukimjada- sik showed significant difference in awareness by the area survey respondents originated. Contrarily, Walnut-gangjung had significantly (p<0.001) higher awareness in rural areas than in more urban areas (e.g., large cities and small and medium-sized cities). Both male and female respondents answered (OR indicated) that the obstacles facing the Korean traditional sweet industry are uncommon products and expensive price. Both male and female respondents said that they had Korean traditional sweets less because it was harder to purchase than western sweets (due to limited access to these sweets), less delicious, and too expensive. Both male and female respondenst suggested that the urgent tasks to popularize the Korean traditional sweets were diversification in shape and ingredient, developing various new flavors, and cheaper products. Both male and female respondents responded that product diversification and strengthened marketing were urgent tasks to industrialize Korean traditional sweets. Therefore, it was believed that failure in generalization was the urgent problem of the Korean traditional sweet industry, and that Korean traditional sweets were harder to purchase because of lower accessibility than western sweets. To popularize Korean traditional sweets, it may be necessary to develop sweets in various shapes and ingredients, flavors suiTable to modern people, become cheaper in price, and have fancier (OR better) packaging.