• Food Science and Preservation
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• v.24 no.8
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• pp.1129-1137
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• 2017

The fringe tree, Chionanthus retusus (Oleaceae) has been used as a natural remedy that helps a paralytic stroke, dementia, phlegm and malaria. This study was conducted to investigate the antioxidant and anti-aging activities of water extracts obtained from the flesh of C. retusus by reflux extraction at room temperature and $80^{\circ}C$, and pressure heating extraction at $110^{\circ}C$, for an increment of their practical use. The highest extraction yield from the flesh of C. retusus was 67.94% extract by pressure heating extraction at $110^{\circ}C$. The content of total polyphenol compounds was the highest by 72.71 mg/g in $80^{\circ}C$ extract by reflux extraction. The highest content of total flavonoid compounds was 7.60 mg/g at $110^{\circ}C$ extract. The results of soluble protein and reducing sugar contents showed the highest content of 4.93 mg/g and 46.77 mg/g in $110^{\circ}C$ extract, respectively. In the analysis of DPPH radical scavenging activity, all extracts showed an excellent effect of 92% in 1.0 mg/mL concentration. The highest effect of ABTS radical scavenging activity was 88.67% at $110^{\circ}C$ extraction in 1.0 mg/mL concentration. Nitrite scavenging ability was the highest as 66.16% at $110^{\circ}C$ extract at pH 1.2 and 1.0 mg/mL concentration. The results of SOD-like activity and xanthine oxidase inhibition activities showed the highest effect of 14.95% and 59.45% at $110^{\circ}C$ extract in 1.0 mg/mL, respectively. Tyrosinase inhibition activity for whitening effect was the highest of 35.31% at $85^{\circ}C$ in 1.0 mg/mL. In the analysis of anti-aging effect, collagenase and elastase inhibition activity showed the highest effects of 37.78% at $110^{\circ}C$ and 20.39% at $80^{\circ}C$, respectively. All results of antioxidant activities and anti-aging effects increased along with the concentration increases. These results indicated that the extracts extracted from the flesh of C. retusus at $80^{\circ}C$ and $110^{\circ}C$ have a large amount of useful ingredients, an excellent antioxidant activity, like as DPPH and ABTS radical scavenging activity, and anti-aging effects to develop functional products than those of $25^{\circ}C$.

• Journal of Food Hygiene and Safety
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• v.36 no.5
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• pp.447-453
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• 2021

In this study, the effectiveness of physical control technology, a combined light sterilization (LED, UV) and hot water treatment in reducing Aspergillus ochraceus for food production environment was investigated. In brief, 1 mL aliquot of A. ochraceus spore suspension (10^7-8 spore/mL) was inoculated onto stainless steel chips, which was then dried at 37℃, and each was subjected to different physical treatment. Treatments were performed for 0.5, 1, 2, 5, 8, and 11 hours to reduce the strains using a light-emitting diode, but no significant difference was confirmed among the treatments. However, a significant reduction was observed on the chips treated with UV-C exposure and hot water immersion. After being treated solely with 360 kJ/m² of UV-C on stainless steel chip, the fungi were significantly reduced to 1.27 log CFU/cm². Concerning the hot water treatment, the initial inoculum amount of 6.49 log CFU/cm² was entirely killed by immersion in 83℃ water for 5 minutes. Maintaining a high temperature for 5 minutes at the site is difficult. Thus, considering economic feasibility and usability, we attempted to confirm the appropriate A. ochraceus reduction conditions by combining a relatively low temperature of 60℃ and UV rays. With the combined treatments, even in lukewarm water, A. ochraceus decreased significantly through the increases in the immersion time and the amount of UV-C irradiation, and the yield was below the detection limit. Based on these results, if work tools are immersed in 60℃ lukewarm water for 3 minutes and then placed in a UV sterilization device for more than 10 minutes, the possibility of A. ochraceus cross-contamination during work is expected to be reduced.

• Journal of Animal Science and Technology
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• v.62 no.5
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• pp.659-667
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• 2020

This study was conducted to evaluate the effects of different levels of crude protein (CP) and protease on nitrogen (N) utilization, nutrient digestibility, and growth performance in growing pigs. A total of six crossbred ([Landrace × Yorkshire] × Duroc) barrows were individually accepted in 1.2 m × 0.7 m × 0.96 m stainless steel metabolism cages. The pigs (average initial body weight of 27.91 ± 1.84 kg) randomly assigned to six diets with six weeks (6 × 6 Latin square design). The experiment was carried out in an environment with a temperature of 23 ± 1.5℃, a relative humidity of 83 ± 2.3% and a wind speed of 0.25 ± 0.03 m/s. The dietary treatments were arranged in a 2 × 3 factorial design with two levels of CP (15.3% or 17.1%) and three levels of protease (0 ppm, 150 ppm, or 300 ppm). The average daily gain and gain to feed ratio (G:F) tended to increase (p = 0.074) with increasing amounts of protease. The low CP level diet reduced (p < 0.050) urinary and fecal N concentrations, the total N excretion in feces, and increased (p < 0.050) N retention. Different protease levels in the diet did not affect (p > 0.05) at N intake, but supplementation of the diets with 300 ppm protease decreased (p < 0.050) the N concentration in urine and feces and tended to increase (p = 0.061) the percentage of N retention retained of the total N intake. The dietary CP level did not affect (p > 0.050) the apparent total tract digestibility (ATTD) of dry matter, digestible energy (DE), and metabolic energy (ME), but diet supplementation with 300 ppm protease showed higher (p < 0.050) ATTD of DE and ME than in the protease-free diet. Therefore, a low protein diet with protease could improve the utilization of nitrogen, thereby reducing the negative effect of N excretion into the environment while maintaining or increasing growth performance compared to a high protein diet.

• Korean Journal of Agricultural Science
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• v.13 no.1
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• pp.123-129
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• 1986

These studies were conducted to elucidate the effect of storage conditions on the changes of chemical components in fruit bodies of oyster mushroom(Pleurotus ostreatus), and the results obtained were as follows. 1. The fruit bodies of oyster mushroom sealed with polyethlene film 0.03 mm thickness maintained their freshness for 15 days at $1^{\circ}C$, 10 days at $5^{\circ}C$ and 3 days at $20^{\circ}C$. 2. The respiration rates of the fruit bodies grown in the rice-straw substrate was 29.7mg $CO_2/kg$ F.W/hr. at $1^{\circ}C$, 32.7mg at $5^{\circ}C$, and 46.3mg at $20^{\circ}C$ during the storage, respectively. The respiration rate showed the highest level at the second day during the storage. 3. The contents of total and reducing sugar during the storage of oyster mushroom rapidly increased at $5^{\circ}C$ until the fifth day following slowly decreased. 4. The content of protein in the oyster mushroom was reduced during the storage, while the free amino acid slightly increased. 5. The change of RNA and DNA contents during the storage of oyster mushroom showed inconsistency on the temperature and the storage period.

• Journal of the Institute of Electronics Engineers of Korea SD
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• v.45 no.4
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• pp.27-35
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• 2008

This work proposes a 14b 150MS/s 0.13um CMOS ADC for SDR systems requiring simultaneously high resolution, low power, and small size at high speed. The proposed ADC employs a calibration-free four-step pipeline architecture optimizing the scaling factor for the input trans-conductance of amplifiers and the sampling capacitance in each stage to minimize thermal noise effects and power consumption at the target resolution and sampling rate. A signal- insensitive 3-D fully symmetric layout achieves a 14b level resolution by reducing a capacitor mismatch of three MDACs. The proposed supply- and temperature- insensitive current and voltage references with on-chip RC filters minimizing the effect of switching noise are implemented with off-chip C filters. The prototype ADC in a 0.13um 1P8M CMOS technology demonstrates a measured DNL and INL within 0.81LSB and 2.83LSB, at 14b, respectively. The ADC shows a maximum SNDR of 64dB and 61dB and a maximum SFDR of 71dB and 70dB at 120MS/s and 150MS/s, respectively. The ADC with an active die area of $2.0mm^2$ consumes 140mW at 150MS/s and 1.2V.

• Journal of the Korean Society of Food Science and Nutrition
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• v.37 no.7
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• pp.934-941
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• 2008

Effect of electron beam irradiation (1 and 2 kGy) on apricot was determined in order to develop preservation techniques to enhance shelf-life during 2 weeks at room temperature. Aerobic bacteria and molds/yeasts in apricot were reduced significantly with the increase of irradiation dose. Hardness of apricots decreased during storage by irradiation. Hunter's color value results showed that lightness and redness of irradiated samples were low compared with control samples. Also, sensory test resulting overall acceptability was not significantly different by 1 kGy irradiation during the storage days. Reducing sugar contents was increased gradually, and value of irradiated samples was high compared with non-irradiated sample. Organic acid contents of 2 kGy irradiated samples was not significantly changed during storage. In pH, total sugar, hydrogen donating activity and vitamin C contents, there were no significant differences between treatments. The electron beam treatment on apricots at 1 and 2 kGy did not affect pH, total sugar, hydrogen donating activity and vitamin C contents but improved microbial safety.

• Korean Journal of Food Science and Technology
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• v.49 no.2
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• pp.162-167
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• 2017

A Katsuobushi smoking machine was developed and evaluated to determine its benzo(a)pyrene reducing effect. The machine was equipped with two heaters for smoking and chamber heating. The smoke-generating system was equipped with a cadmium sulfide (CdS) smoke sensor, an on/off controller, and a rotating feeder with a smoke inlet. Raw bonito was steamed and then smoked under three smoke levels. After smoking at $45^{\circ}C$ for 108 h, the benzo(a)pyrene concentrations were 5.87, 7.83, and $11.41{\mu}g/kg$ at the low, middle, and high smoke levels, respectively. The benzo(a)pyrene concentrations after low-level smoking at 45, 65, and $85^{\circ}C$ for 108 h were 5.87, 4.82, and $3.27{\mu}g/kg$, respectively. Accordingly, the optimal conditions for benzo(a)pyrene reduction were a lower smoke level and higher smoking temperature. These optimal smoking conditions can be implemented with the newly developed machine, but is not possible using a conventional Katsuobushi smoking machine.

• Fire Science and Engineering
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• v.28 no.4
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• pp.57-63
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• 2014

This study was performed to test the combustive properties of Medium Density Fibreboard (MDF) specimens treated with piperazinomethyl-bis-phosphonic acid (PIPEABP), methylpiperazinomethyl-bis-phosphonic acid (MPIPEABP), and N,N-dimethylethylenediaminomethyl-bis-phosphonic acid (MDEDAP). MDF Plates were painted in three times with 15 wt% solution of the alkylenediaminoalkyl-bis-phosphonic acids at the room temperature, respectively. After drying specimen treated with chemicals, combustive properties were examined by the cone calorimeter (ISO 5660-1). It was indicated that the specimens treated with chemicals showed the later time to peak mass loss rate ($TMLR_{peak}$) = (340475) s than that of virgin plate by reducing the burning rate. In adition, the specimens treated with chemicals showed the higher $CO_{mean}$ production (0.0883~0.0963) kg/kg than that of virgin plate. Especially, the specimens treated with chemicals showed the higher mean smoke extinction area ($SEA_{mean}$) ($5m^2/kg{\sim}21.5m^2/kg$) than that of virgin plate. Thus, It is supposed that the combustion-retardation properties were improved by the partial due to the treated alkylenediaminoalkyl-bis-phosphonic acids in the virgin MDF Plate. However, It gave a negative effect on smoke reduction.

• Journal of Food Hygiene and Safety
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• v.30 no.1
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• pp.92-97
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• 2015

The aim of this study is to examine the removal efficiency of pathogen (Escherichia coli O157:H7 and Salmonella typhimurium) on meat and fish products (packing condition: vacuum or not and storage temperature: $4^{\circ}C$ or $-20^{\circ}C$) repeatedly exposed at low-dose gamma irradiation. In case of meat products (beef and chicken), E. coli O157:H7 was not observed at the level of 2 kGy single gamma irradiation and 0.5 kGy repeated gamma irradiation and S. Typhimurium was not observed at the level of 2 kGy single gamma irradiation and 1 kGy repeated gamma irradiation. In case of fish products, E. coli O157:H7 and S. Typhimurium were not detected at the level of 0.5 kGy single and repeated gamma irradiation. These results showed that microorganisms on fish products were more efficiently removed than those of meat products with low-dose gamma irradiation. Generally, each packing condition made no difference. However, the products (fish and meat) stored at $-20^{\circ}C$ needed more higher dose gamma irradiation than products at $4^{\circ}C$.

• Korean Journal of Food Science and Technology
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• v.41 no.5
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• pp.566-571
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• 2009

The principal objective of this study was to use a fermentation and extrusion process in order to improve the antioxidant properties of original Sangmaksan (ES), containing maekmoondong, omija, and white ginseng. The antioxidant activities of fermented Sangmaksan prepared with different types of ginseng [white (FSW), red (FSR), and extruded white (FSE)], were investigated. The white ginseng powder was extruded at 20% moisture content and $120^{\circ}C$ of the maximum process temperature at the barrel. The antioxidant properties of Sangmaksan were increased after fermentation. Interestingly, the fermented Sangmaksan containing the extruded white ginseng evidenced more potent antioxidant properties than the fermented Sangmaksan containing white ginseng. The content of total phenolic compounds, DPPH-radical scavenging activity, acidic polysaccharide, reducing power, and total anthocyanin were highest with FSR, followed by FSE, FSW and ES, respectively. Additionally, superoxide dismutase-like activity and total flavonoid contents were highest in the fermented Sangmaksan containing extruded white ginseng. In conclusion, it can be asserted that the fermentation and extrusion process utilized in this study may prove to be an effective new process for the production of high-quality Sangmaksan.