• Journal of Korean Society of Occupational and Environmental Hygiene
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• v.34 no.1
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• pp.85-97
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• 2024

Objectives: This study was intended to investigate the revision status of the occupational exposure standards for aluminum at home and abroad; to investigate worker exposure at domestic aluminum manufacturing and handling workplaces; to conduct social and economic evaluation for the revision of domestic aluminum exposure limits. Methods: We investigated the current status of occupational exposure limits for aluminum at home and abroad, and analyzed supporting data. An exposure survey was conducted targeting domestic aluminum manufacturing and handling workplaces. Based on these, revised aluminum occupational exposure limits were proposed. Results: The major aluminum exposure limits at home and abroad show a notable difference. The toxicity of aluminum, which was revealed through animal experiments and epidemiological investigations. The average concentration of aluminum in the air at 12 workplaces was 0.016 mg/m³, and the maximum was 0.0776 mg/m³. When total dust and respiratory dust were measured side by side and simultaneously for the same process, 12.1% of the total mass concentration of aluminum dust was respiratory dust. As a result of measuring and comparing the size distribution of dust with an optical particle counter in real time, 48.1% of the total dust in the form of welding fume and pyro-powder was respiratory dust. Based on the literature review and workplace survey, three proposals for changing the aluminum exposure limit were proposed. Proposal (1): For all types, 10 mg/m³ is unified as the exposure limit except for soluble salts and alkyls. Proposal (2): 1(R) mg/m³ as the exposure limit for all forms except soluble salts and alkyl. Proposal (3): 1(R) mg/m³ for pyro-powder and welding fume, and 10 mg/m³ for metal dust, aluminum oxide, and insoluble compounds as exposure standards. A pyro-powder was defined as dry aluminum powder of 200 mesh size (74 ㎛) or smaller (larger size classified as metal dust). Reason for setting: In the workplace survey, the ratio of respiratory dust to total dust was analyzed to be about 1:10, so it was judged that the domestic standard and the ACGIH standard were compatible. Conclusions: In all scenarios according to the revision of the exposure standard, the B/C ratio was greater than 1 or only benefits existed, so it was evaluated as sufficiently reasonable as a result of the socio-economic evaluation.

• Food Science and Preservation
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• v.14 no.1
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• pp.47-53
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• 2007

Soybean curd was mixed with onion powder to develop new foods, and changes in quality characteristics were investigated. The moisture content of onion soybean curd rose as the proportion of onion powder increased Whiteness (as measured by the L value) was high in soybean cud admixed with 0.1% (w/v) onion powder, Redness (the a value) was not significantly altered (the readings were 1.03-1.54) on addition of various onion powder concentrations. Yellowness (the b value) was similarly unaffected (readings 13.00-13.93) when various levels of onion powderwere added. Free sugar analysis showed that glucose was high in soybean curd (67.22 g/100 g) admixed with 0.1% (w/v) onion powder, The main organic acid was tartaric acid, and control organic acids included citric and oxalic acids at high levels. The major free amino acids were L-arginine, ${\gamma}-Amino-n-butyric$ acid, L-histidine, L-glutamic acid, L-serine, L-tyrosine and L-threonine, and amino acid content were high in soybean curd admixed with 0.2% (w/v) onion powder. Major phenolic compounds of onion soybean curd were quercitrin, protocatechuic acid and caffeic acid. The hardness of onion soybean curd was similar to that of the control when onion powder was added to 0.1% or 0.2% (w/v), and decreasedmore onion powder was added. Organoleptic qualities dropped as onion powder levels increased. In summary, onion powder addition to soybean curd is optimal at the 0.2% (w/v) level..

• Journal of the Mineralogical Society of Korea
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• v.19 no.3 s.49
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• pp.189-195
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• 2006

Compression work on a pyrite powder has been carried out using energy dispersive X-ray diffraction (EDXRD) with Mao-Bell type diamond anvil cell (DAC) and synchrotron radiation(SR) at room temperature. It has been reported the bulk moduli of pyrite show the large variations depending on the experimental conditions as well as the apparatus used. Thus, two kinds of sample in different pressure transmitting media of both NaCl and MgO powder emerged in alcoholic fluids were subjected to measure their compressibilities. Bulk moduli thus obtained are 138.9 GPa and 198.2 GPa, respectively, and this result contradicts to the anticipated values according to the hydrostaticity conditions of the sample chamber. This might be due to the alcoholic fluids phase transition mainly with the side effects from the difference of both solid state detector (SSD) used and E*d value applied. All experiments were performed at the Beam Line 1B2 of Pohang Light Source (PLS).

• Microbiology and Biotechnology Letters
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• v.26 no.4
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• pp.369-372
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• 1998

Microbial insecticide formulations were prepared by liquid and semi-solid fermentations using Bacillus thuringiensis subsp. kurstaki, HL-106 (BTK-HL106), B. thuringiensis subsp. israelensis HL-63 (BTI-HL63) and B. sphaericus 1593 (BS-1593) strains. The liquid fermentation medium contained molasses 2%, dextrose 1.5%, peptone 2%, D-xylose 0.025%, CaCl$_2$ 0.1%, K$_2$HPO$_4$ 0.1%, KH$_2$PO$_4$ 0.1%, MgSO$_4$$.$7H$_2$O 0.03%, FeSO$_4$$.$7H$_2$O 0.002%, ZnSO$_4$$.$7H$_2$O 0.02%. The composition of the semi-solid fermentation medium was rice bran 45.2%, zeolite 31%, yeast powder 0.02%, corn powder 5%, dextrose 3%, lime 0.3%, NaCl 0.06%, CaCl$_2$ 0.02%, and H$_2$O 15.42%. Insecticide formulations produced in the liquid fermentation named BTK-HL106, BTI-HL63 and BS-1593 pesticides and those in the semi-solid fermentation were designated as BTK-HL106-1, BTI-HL63-1 and BS-1593-1 pesticides, respectively. The number of spore (endotoxin crystals) was 2.65${\times}$10$\^$9/ spores per $m\ell$ in the BTK-HL106 and 3.5${\times}$10$\^$10/ in the BTK-HL106-1 3.8${\times}$10$\^$9/ spores in the BTI-HL63 and 7.0${\times}$10$\^$10/ in the BTI-HL63-1, and 7.5${\times}$10$\^$9/ in the BS-1593 and 1.4${\times}$10$\^$10/ in the BS-1593-1. The spores in the BS-1593 formulation was produced two times more than the other formulations. The spores in the BTI-HL63-1 were contained twice than those in the BTK-HL106-1, and five times than those in the BS-1593-1. The results indicated that spore (endotoxin crystals) productions in the semi-solid fermentation increased about ten times than those in the liquid fermentations. $LC_{50}$s of the BTI-HL63 and BS-1593 were 4.5 $\mu\textrm{g}$, and those of the BTI-HL63-1 and BS-1593-1 were 1.5 $\mu\textrm{g}$. $LC_{50}$ of the BTK-HL106 was 1.5 mg and that of the BTK-HL106-1 was 0.9 mg. The $LC_{50}$s of the formulations in the semi-solid fermentations showed about two to three times higher than those in the liquid fermentations.

• The Korean Journal of Food And Nutrition
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• v.31 no.6
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• pp.821-827
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• 2018

Ecklonia cava which is a kind of phaeophyta and belongs to Laminariales Alariaceae is a perennial seaweed distributed over Jeju and Dokdo islands. The purpose of this study evaluate antioxidant activities of Ecklonia cava crackers. Crackers were prepared with different measurements (0, 2, 4, 6, 8 g) of Ecklonia cava; indicated as S1, S2, S3, S4 and S5, and are used to examine and compare antioxidant activities, and quality characteristics. Ecklonia cava powder was used, after being extracted with 70% ethanol in hot water and done in freeze dehydration. To examine antioxidant activities of Ecklonia cava and cracker, DPPH radical scavenging activity, total phenolic and reducing power were tested. Total phenolic content was 36.86 mg GAE/g. DPPH radical scavenging activity and reducing power showed good vitality as amounts of Ecklonia cava powder increased (p<0.001). pH level decreased as amounts of power increased. L (lightness) values and b (yellowness) values decreased with an increased concentration of Ecklonia cava powder (p<0.001), whereas (redness) values didn't show tendency. S5 indicated the lowest spreadness. According to sensory evaluation, S4 (6 g) was preferred the most in terms of color, flavor, taste, appearance, texture, and overall palatability. Results suggest that Ecklonia cava powder has antioxidant effect and is useful as a functional food resource.

• Korean Journal of Plant Resources
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• v.33 no.6
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• pp.696-706
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• 2020

Cordyceps has been used in traditional Chinese medicine more than 2000 year ago. In this study, the new Cordyceps militaris was founded and isolated from O-dae mountain in Korea, and was identified its genetic characteristics. The newly isolation strain HB8 was most closet to Cordyceps militaris W141449 (99.82%), Cordyceps militaris JLCY-LI819 (99.82%) and Cordyceps militaris 4642 (99.81%), respectively. the genotypic result was show that train HB8 was belonging to the Cordyceps militaris genus, therefore, Cordycep militaris HB8 proposed with accession number MT835161. This study we find the optimal condition for production of cordycepin from Cordyceps militaris HB8 was 8 mg/g (200 g of pupa, 1 g of KH₂PO₄, 0.5 g of K₂HPO₄, 20 g of glucose, 1 g of MgSO₄, 0.05 g of vitamin B1, and 1 mg of NAA per liter; light condition 300-700 Lux and day/night was 14 h/10 h) and the optimum condition for the production of adenosine was 2.6 mg/g (15 g of skim milk powder, 1 g of KH₂PO₄, 0.5 g of K₂HPO₄, 20 g of glucose, 1 g of MgSO₄, 0.05 g of vitamin B1, and 1 mg of NAA per liter; light condition 300-700 Lux and day/night was 14 h/10 h).

• Korean journal of food and cookery science
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• v.29 no.1
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• pp.19-28
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• 2013

This study was carried out to investigate the quality characteristics and storage of noodle with added flowering cherry fruit powder. Wet noodles were prepared at concentration of 1, 2, and 3% (w/w) of the fruit based on flour weight. Moisture content of the noodles with or without flowering cherry fruit powder was 33.09~33.50%. Ca, K and Mg contents of flowering cherry fruit noodle were increasing at increasing concentrations of flowering cherry fruit powder. Cooked weight, volume, and water absorption decreased with increased fruit powder, whereas turbidity increased. For Hunter's color values of noodles, L (lightness) and b (yellowness) values decreased with increasing concentration of flowering cherry fruit powder, whereas a (redness) value increased. For mechanical characteristics of the noodles, adhesiveness of cooked noodle with flowering cherry fruit powder were higher than those of control. The pH of flowering cherry fruit noodle was lower than that of control during storage. Bacterial counts of wet noodle with flowering cherry fruit powders were lower than those of the control on the 10th day of storage at $5^{\circ}C$. From the sensory evaluation of 20's, texture, taste, and overall preference were not significantly different between the control and the fruit groups, but the color scores of 2% and 3% flowering cherry fruit noodle were significantly higher than that of 1% fruit noodle (p<0.05). In 40's sensory evaluation, color and overall preference scores of flowering cherry fruit noodle were significantly higher than those of control. In conclusion, the results of this study were suggested that the addition of flowering cherry fruit powder in combination with flour was tended to improve antimicrobial effects during storage when compared to control.

• Culinary science and hospitality research
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• v.20 no.4
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• pp.127-143
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• 2014

This study investigated color barley powder substituted for wheat flour in bread recipes with the amounts of 0%, 5%, 10%, 15% and 20%. Color barley powder consisted of 9.35% of moisture content, 9.37% of crude protein, 1.64% of crude fat and 2.96% of crude ash. Water soluble dietary fiber is 3.21, insoluble dietary fiber is 4.91, total dietary fiber content is 8.12, and ${\beta}$-glucan is 49.31. DPPH radical scavenging activity is 56.76%, total phenol content is 234.34. The farinograph measurement result of the bread made with color barley powder showed that consistency, water absorption, development time and time breakdown have decreased. The alveogram measurement result of the bread made with color barley powder showed that overpressure, extensibility, swelling index and deformation energy have increased. The amylograph measurement result of the bread made with color barley powder showed that peak viscosity, hot past viscosity and breakdown have decreased. Baking loss and specific loaf volume have decreased as the color barley powder content increased. The chromaticity measurement result showed that the 'L' and 'b' of bread have increased as the color barley powder content increased, while the chromatic 'a' value increased. The texture measurement result showed that the hardness and gumminess of bread have increased as the color barley powder content increased. cohesiveness, springiness and chewiness have decreased. Overall preference scores showed a high overall acceptability for the bread made with 10% color barley powder.

• Journal of Life Science
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• v.10 no.6
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• pp.564-569
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• 2000

This study was designed to investigate the effect of silkworm (Bombyx mori L.) powder on lipofuscin, acetylcholine (ACh) and its related enzyme activities in brain of rats. Sprague-Dawley (SD) male rats ($160{\pm}10g$) were fed basic diet (control group), and experimental diets (SWP-200 and SWP-400 groups) added 200 and 400 mg/kg BW/day for 6 weeks. In case of liver membranes, lipofuscin (LF) levels resulted in a slight decreases (4.6% and 11.5%, respectively) in SWP-200 and SWP-400 groups compared with control group. But in case of barin as the most sensitive organ, LF levels were remarkably inhibited about 16.7% and 20.0% in SWP-200 and SWP-400 groups compared with control group. There were no significant differences in acetylcholine (ACh) syntheses as a very important neurotransmitter, and choline acetyltransferase (ChAT) activities as a synthesis enzyme of ACh, and acetylcholinesterase (AChE) activities as a hydrolysis enzyme, which were concerned in transmission of neuron through synapses in brain of SWP-200 and SWP-400 groups compared with control group. Monoamine oxidase-B (MAO-B) activities were significantly inhibited (about 10.2%) in brain of SWP-400 groups compared with control group. These results suggest that inhibiting effects of LF accumulation and MAO-B activity of silkworm powder (SWP) may play a pivotal role in attenuating a various age-related changes for improvement of brain function.

• Food Science and Preservation
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• v.24 no.8
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• pp.1188-1194
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• 2017

Gochujang, a traditional Korean food, is fermented by mixing red pepper powder, various grain, meju and salt. Changes in the kind of ingredients and fermentation method could increase health functionalities. In this study, in vivo anti-colitis effects of gochujang prepared with mixed grains, bamboo salt baked 3 times and meju starters on DSS-induced colitis in C57BL/6 mice were studied. We prepared gochujang prepared with mixed grains (MG), bamboo salt, and Aspergillus oryzae (A) and Baccillus subtilis (B) mixed starters (MG-AB) and gochujang prepared with MG, bamboo salt and A, B and Lactobacillus plantarum (L) mixed starters (MG-ABL). MG-AB and MG-ABL significantly increased body weight and colon length compared to the control (p<0.05). MG-ABL showed significantly decreased interleukin-6 (IL-6) expression in serum compared to the control and MG-AB group (p<0.05). MG-ABL also regulated mRNA and protein levels of pro-apoptotic Bcl-2-associated X protein (Bax) and anti-apoptotic B-cell lymphoma-2 (Bcl-2) in the mice colon tissue (p<0.05). Therefore, MG-ABL exhibited the increased anticolitis effects by inhibiting damage of colon tissue, probably by regulating a pro-inflammatory cytokine of IL-6 and regulated apoptosis related genes. These results indicated that gochujang changed with good ingredients and starters had colitis preventive effects and might be due to active compounds in mixed grain and bamboo salt, and produced by L during the fermentation of gochujang.