• Food Science and Preservation
• /
• v.3 no.2
• /
• pp.145-148
• /
• 1996

This paper was carried out to investigate change in the initial microorganism of Pepper which were treated with ozonated water for microbial decontamination. When ozonated water was 30, 60, 90minutes treatment, there was decrease in the overall total microbial of the black & white pepper. Total lactic acid bacteria died completely after contacted with ozonated water for 60minutes but the inhibition rate on the total aerobic bacteria of black & white pepper were 62% and 96%, respectively. Total aerobic bacteria of four packing material was increased after 1 months of storage at 37$^{\circ}C$ when it had treated with 90minutes ozone reaction Then, there was no significant changes in the piperin contents.

• Mycobiology
• /
• v.42 no.1
• /
• pp.59-65
• /
• 2014

Entomopathogenic fungi are promising pest-control agents but their industrial applicability is limited by their thermosusceptibility. With an aim to increase the thermotolerance of Isaria fumosorosea SFP-198, moisture absorbents were added to dried conidial powder, and the relationship between its water potential and thermotolerance was investigated. Mycotized rice grains were dried at $10^{\circ}C$, $20^{\circ}C$, $30^{\circ}C$, and $40^{\circ}C$ and the drying effect of each temperature for 24, 48, 96, and 140 hr was determined. Drying for 48 hr at $10^{\circ}C$ and $20^{\circ}C$ reduced the moisture content to < 5% without any significant loss of conidial thermotolerance, but drying at $30^{\circ}C$ and $40^{\circ}C$ reduced both moisture content and conidial thermotolerance. To maintain thermotolerance during storage, moisture absorbents, such as calcium chloride, silica gel, magnesium sulfate, white carbon, and sodium sulfate were individually added to previously dried-conidial powder at 10% (w/w). These mixtures was then stored at room temperature for 30 days and subjected to $50^{\circ}C$ for 2 hr. The white carbon mixture had the highest conidial thermotolerance, followed by silica gel, magnesium sulfate, and then the other absorbents. A significant correlation between the water potential and conidial thermotolerance was observed in all conidia-absorbent mixtures tested in this study (r = -0.945). Conidial thermotolerance in wet conditions was evaluated by adding moisturized white carbon (0~20% $H_2O$) to conidia to mimic wet conditions. Notably, the conidia still maintained their thermotolerance under these conditions. Thus, it is evident that conidial thermotolerance can be maintained by drying mycotized rice grains at low temperatures and adding a moisture absorbent, such as white carbon.

• Journal of Korean Society of Water and Wastewater
• /
• v.19 no.5
• /
• pp.613-618
• /
• 2005

In analysis of pipelines or pipe network we calculated the friction loss using Hazen-Williams or Manning formula approximately, or found one by friction coefficient from Moody diagram graphically. The friction coefficient is determined as a function of relative roughness and Reynolds number. But the calculated friction coefficient by Hazen-Williams or Manning formula considered roughness of pipe or velocity of flow. The friction coefficient in Darcy-Weisbach equation was obtained from the Moody diagram. This method is manual and is not exact from reading. This paper is presented numerical solution of Colebrook-White formula including variables of relative roughness and Reynolds number. The suggested subroutine program by an efficient linear iteration scheme can be applied to any pipe network system.

• Animal Systematics, Evolution and Diversity
• /
• v.36 no.4
• /
• pp.416-419
• /
• 2020

Two cold water species of dendronotid nudibranchs are described for the first time in Korea: Dendronotus frondosus (Ascanius, 1774) and Dendronotus robilliardi Korshunova, Sanamyan, Zimina, Fletcher & Martynov, 2016. Dendronotus frondosus is characterized by the color pattern of deep dark-brown with white specks and mottles on the dorsum. Dendronotus robilliardi is distinguished by the body of translucent white with milky stripes and orange-brown markings in papillae, and D. robilliardi from Korean water is commonly examined with white dots on the anterior dorsum. Images of external morphology and brief re-descriptions of two species were provided. Further, we confirmed the opinion of Korshunova et al. that the Korean D. albus image by Koh would be D. robilliardi.

• Preventive Nutrition and Food Science
• /
• v.20 no.3
• /
• pp.183-189
• /
• 2015

In the present study, an optimum protease was selected to hydrolyze the egg white liquid protein for the antioxidant peptides. Alcalase treatment yielded the highest amount of ${\alpha}$-amino groups (15.27 mg/mL), while the control (no enzymatic hydrolysis) showed the lowest amount of ${\alpha}$-amino groups (1.53 mg/mL). Alcalase also gave the highest degree of hydrolysis (DH) value (43.2%) and was more efficient for egg white liquid hydrolysis than the other enzymes. The Alcalase hydrolysate had the highest radical-scavenging activity (82.5%) at a concentration of 5.0 mg/mL. The conditions for enzymatic hydrolysis of egg white liquid with Alcalase were selected as substrate : water ratio of 2:1. Five percent Alacalse treatment did not show significant (P>0.05) increases of DH and ${\alpha}$-amino nitrogen content after 24 hhydrolysis. Thirty two hour-hydrolysis with 5% Alcalase is sufficient to make antioxidative egg white liquid hydrolysate from egg white liquid. DPPH and ABTS radical-scavenging activities were significantly (P<0.05) higher after enzymatic digestion. These results suggest that active peptides released from egg-white protein are effective radical-scavengers. Thus, this approach may be useful for the preparation of potent antioxidant products.

• KOREAN JOURNAL OF CROP SCIENCE
• /
• v.10
• /
• pp.51-56
• /
• 1971

To make certain of the white tip infection on rice, nematodes isolated from the rice seeds grown at Chongdo-goon Isu-myun and Kimje-goon Chooksan-myun were artificially inoculated and their pathway was studied. Also, studies were made for the hot water seed treatment as a measure of white tip control at different levels of water temperature and their germinablity was checked. The results are summarized as follows; 1. Causal nematodes survive in the paddy soil and cause white tip year after year. 2. Causal nematodes can survive in the rice seeds as long as the seeds loose their germinability. 3. Causal nematodes can disseminate throught the irrigation water. 4. Causal nematodes can disseminate through the soil move from a place to other place. 5. Causal nematodes can infect all of the parts of the rice and they can disseminate through any of the parts of rice. 6. The hot water treatment at 5$0^{\circ}C$ for 60 minutes were not effective controlling causal nematodes. But, either treatment of at 55$^{\circ}C$ for 15-20 minutes or at 6$0^{\circ}C$ for 10-15 minutes were effective and germination of seeds was not affected.

• Korean Journal of Plant Resources
• /
• v.11 no.3
• /
• pp.290-295
• /
• 1998

Presowing treatements to seed are reasonable for elevating the seedling production efficiency. This experiment was carried out to determine the effects of $GA_3$ [0 (water) : 0.01 mM] and light qulaity (red : white) simultaneously treated before sowing on seedling emergence and growth of tobacco (Nicotiana tabacum L.) cv NC 82 and Burley 21. Red or white light was illuminated 12 hours a day while seeds of the cultivars were imbibed with either water or $GA_3$ 0.01 mM for 3 days. Seedling emergence was measured up to 20 days after sowing but morphological characters and dry weights were done 40 days. The seedling emergence rate of cv NC 82 was more affected by light quality and $GA_3$ pretreatments than that of cv Burley 21. Light quality more influenced the rate than $GA_3$ while red light or water imbibition enhanced the rates of the two cultivars compared to the other treatement. Although mean plant height and leaf number per seedling were nearly equal between the treatements, red light declined leaf area per seedling of cv Burley 21 of which seeds were imbibed in water but white light decreased the areas of both cultiars of which seeds were soaked in $GA_3$solution. Shoot dry weight was greater in cv NC 82 but less in cv Burley 21 pretreated with red light, and root dry weight showed the reverse result in white light, meaning that presowing light and $GA_3$ treatments could be changed the seedling development and growth of tobacco.

• Korean Journal of Fisheries and Aquatic Sciences
• /
• v.50 no.3
• /
• pp.257-262
• /
• 2017

This study was conducted to investigate the growth and skin color of red- and white-colored fancy carp Cyprinus carpio var. koi juvenile reared at different water temperatures (21, 24, 27, and $30^{\circ}C$) for eight weeks. Two experimental diets were prepared to contain 10% Arthrospira platensis or 10% Arthrospira pacifica powder. After the feeding trial, survival was 100% in all group. Weight gain of fish reared at 24, 27, and $30^{\circ}C$ was higher than $21^{\circ}C$ group. Feed efficiency was not affected by water temperature and dietary Arthrospira sp. Daily feed intake tended to increase with water temperature. The $a^*$ value of skin coloration was affected by Arthrospira sp., but not by water temperature. Fish fed the diet containing A. pacifica powder reared at $27^{\circ}C$ had the highest $a^*$ value among the groups. Total carotenoids were highest in fish fed the diet containing A. pacifica powder reared at $21^{\circ}C$. Based on the results of this study, we conclude that 24-$30^{\circ}C$ water temperature was the optimal range for growth, and dietary inclusion of A. pacifica improved the skin redness of red- and white-colored fancy carp reared at $27^{\circ}C$.

• Journal of Life Science
• /
• v.26 no.8
• /
• pp.928-935
• /
• 2016

Hypsizygus marmoreus (white cultivar), also called white beech mushrooms, are edible mushrooms commercially cultivated in Korea and Japan. This study was carried out to evaluate the antioxidant properties of H. marmoreus. H. marmoreus fruit bodies were divided into pileus and stipe. The pileus and stipe were extracted into water and 80% ethanol and their antioxidant activities were analyzed. The total polyphenol content was highest in the water extract (pileus 1137.39±0.38 mg of GAE (gallic acid equivalents)/100 g, stipe 700.86±0.06 mg of GAE/100 g) compared to the ethanol extract (pileus 923.47±0.18 mg of GAE/ 100 g, stipe 324.05±0.03 mg of GAE/100 g). Ethanol extracts from pileus showed better scavenging ability on DPPH (47.32±0.23% at 10 mg/ml) and ABTS (57.33±0.10% at 10 mg/ml) than the stipe and water extract groups. Water extract from pileus were more effective in reducing power and ORAC (oxygen radical absorbance capacity) value than stipe and ethanol extract. The toxicity of water and ethanol extracts was investigated using WST-1 (Water Soluble Tetrazolium salt) assay on the mouse macrophage cell line RAW 264.7. Overall, total polyphenol content and antioxidant activities of extracts from H. marmoreus increased in a dose dependent manner while pileus was showed better total polyphenol content and antioxidant activities than stipe.

• Journal of Ginseng Research
• /
• v.38 no.2
• /
• pp.146-153
• /
• 2014

A systematic comparison of the physicochemical properties of white ginseng (WG), extruded white ginseng (EWG), red ginseng (RG), and extruded red ginseng (ERG) was performed. The aim of the present study was to identify the effects of the physicochemical properties of ginseng by extrusion cooking. The highest value of the water absorption index (WAI) was 3.64 g/g obtained from EWG, and the highest value of the water solubility index (WSI) was 45.27% obtained from ERG. The ERG had a better dispersibility compared with other samples. Extrusion cooking led to a significant increase in acidic polysaccharide and total sugar content but resulted in a decrease in crude fat and reducing sugar contents. Enzyme treatment led to a sharp increase in acidic polysaccharide content, especially the cellulose enzyme. Extrusion cooking led to a significant increase in 2,2-diphenyl-1-picrylhydrazyl (DPPH) radical scavenging activity and reducing power, and the increases in WG and RG were 13.56% (0.038) and 3.56% (0.026), respectively. The data of this study provide valuable information about the effects of extrusion on quality changes of EWG and ERG.