• The Korean Journal of Pesticide Science
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• v.10 no.1
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• pp.15-21
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• 2006

In order to monitor the pesticide residues in/on peppers and pepper powder and to assess their risk, pesticides in/on green pepper from 10 farmgates and fresh red pepper from 9 farmgates in Chungbuk area and pepper powder from 6 wholesale markets in Cheongju city were analyzed with a GLC and an HPLC. Also, pepper powder made by pulverization of the dried red pepper was analyzed to elucidate the change of pesticide residues in fresh red pepper by oven-drying. The number of pesticides detected from peen pepper, fresh red pepper, dried red pepper and pepper powder were 9, 12, 12, and 17, respectively, including 10 pesticides (one fungicide and nine insecticides) which were exceeded the maximum residue limits (MRLs). The exceeding rate of the MRL were higher in dried red pepper and pepper powder than in green pepper and fresh red pepper. Although some pesticides in peppers and pepper powder exceeded the MRLs, their estimated daily intake(EDI) were less than 1.6% of their acceptable daily intakes(ADIs), suggesting that it would be estimated to safe. By oven-drying of fresh red pepper at $65^{\circ}C$ for 72 hours, the weight of dried red pepper was from 1/5.9 from 1/7.8 of fresh red pepper, while the concentration of pesticide residue in dried red pepper increased from 1.7 to 8.2 times, suggesting that further reconsideration was required for the MRL of pepper powder.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.25 no.5
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• pp.341-358
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• 1992

In order to estimate energy budgets of Palaemon macrodactylus, larvae of the shrimp were reared in the laboratory at constant conditions $(25^{\circ}C: 31-32\%o),$ and then juvenile to adult of the shrimp were reared at $15^{\circ}C\;and\;25^{\circ}C$ in the laboratory. Energy used by the reared shrimps were calculated from estimates of data on feeding, growth, molting, metabolism, nitrogen excretion, and energy content. Juveniles and adults reared in the laboratory, which fed on Artemia nauplii, had an average daily growth rates of 0.079 mm/day at $15^{\circ}C\;and\;of\;0.122mm/day\;at\;25^{\circ}C$. The average growth factor* of P. macrodactylus males and females ranged from $3.2\%$ for adult to $13.2\%$ for juveniles individuals, respectively. Intermolt periods were related to body size of the shrimp and to temperature. Average laboratory growth curves were calculated from data on growth factors and intermolt periods to body size of the shrimp at $15^{\circ}C\;and\;25^{\circ}C$. The calorie contents of the shrimp, their molts, eggs and larvae were determined by biochemical composition and oxygen bomb calorimetry. The average amount of energy used in growth for larvae and juvenile to adult were 4.94 cal and 4.55 cal per dry weight in milligram, respectively. The ammount of oxygen used in metabolism was calculated from size, temperature-specific respiration rate. To convert the ammount of oxygen used in respiration into the equivalent energy lost heat was estimated from the data on chemical composition for the larvae and adult, the values was 4.58 cal/ml $O_2$. The energy content per egg was 0.078 cal. The assimilation efficiency estimated by nitrogen content of food and egested faeces gave $61.5\%$ for the larvae. The efficiencies for juvenile to adult ranged between $79.4\%$ and $90.1\%$ The gross growth efficiencies $(K_1)$ and net growth efficiencies $(K_2)$ of P macrodactylus showed $18.33\%\;and 32.63\%$ for total larval stages, ranged from $21.30\%\;to\;31.04\%\;and\;from\;30.03\%\;to\;39.34\%$ for juvenile to adult, respectively.

• Korean Journal of Food Science and Technology
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• v.31 no.5
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• pp.1275-1282
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• 1999

The quality changes by storage conditions were examined in order to establish the optimum CA storage conditions of unbagged and bagged 'Fuji' apples. The weight retention rate of apples was higher in CA than air storage, but there was no significant difference among CA conditions. Bagged apples had higher weight than unbagged apples under the same condition. The loss of flesh firmness, titratable acidity and green color of apples was retarded more effectively in 1% $O_2$ than 3% $O_2$ storage, and in $0^{\circ}C$ and 3% $CO_2$ than $2^{\circ}C$ and 1% $CO_2$ with 1% $O_2$ Titratable acidity tended to decrease more rapidly in bagged than unbagged apples. Soluble solid was not affected by storage conditions. Internal browning was developed within 2 months in 1% $O_2$ and 3% $CO_2$ storage, but there was no significant difference according to storage years and bagging treatment. At the sensory evaluation, unbagged apples were rated as higher quality than bagged apples after 8 months storage, and the hardness, juiciness, acidity and overall acceptability of apples stored in 1% $O_2$ were Higher than those in 3% $O_2$ but those of apples stored in 1% $O_2$ were not affected by $CO_2$(1, 3%) and temperature(0,\;$2^{\circ}C)$ differences. Above results suggest that the optimum CA storage condition of 'Fuji' apples is $0^{\circ}C,\;1%\;O_{2}+1%\;CO_2$.

• Journal of Dairy Science and Biotechnology
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• v.34 no.2
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• pp.117-135
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• 2016

The present study was performed to develop a functional raw food material from hydrolyzed whey protein powder (23%-GNANA) medication containing sialic acid as a marker compound that is naturally occurring at 7% concentration in GMP (glycomacropeptide). GMP is used worldwide in foodstuffs for babies and infants and is obtained from the milk protein as safe food. While the purpose of our detailed evaluation was aimed to assess preliminary NOAEL values for and above 2,000 mg/kg/day, a clinical dose allowance for 23%-GNANA (as per characteristic of a functional health product, a highly refined test substance of 23% (v/v) sialic acid combined in GMP), at the same time we also wanted to assess the safety of GMP hydrolyzate lacking sialic acid but with identical properties as GMP. Animal safety evaluation was conducted using 23%-GNANA as the test substance, produced from hydrolyzed whey protein powder (product name: HELICOBACTROL-23; provided by Medinutrol Inc. [Korea]; composed of 23% sialic acid and GMP protein) after isolating the sialic acid using enzymes approved as food additives, with GMP as a raw material, and subsequently increasing the content of xx up to 23% through 80% (v/v) ethanol soaking and concentrating, in accordance with GLP Guideline. The animal safety evaluation mentioned above was made on the basis of toxicity in SPF Sprague-Dawley female and male rats dosed with 10 mL of the test substance diluted to 0, 1,250, 2,500, and 5,000 mg/kg directly into their stomachs for 90 d. This was determined in terms of the general symptoms and animal viability, weight and amount of feed intake, eye examination, uracrasia tests, hematological and blood biochemical disorder tests, blood coagulation test, abnormal intestine weight, abnormalities during postmortem and histopathological examinations. Statistical significance was set at P<0.05. Based on the toxicity determination, a certain minor effect associated with the test substance was observed in male rats with no major effects of the tested substance, in comparison with the control group dosed with sterilized water. Nevertheless, the NOAEL value, evaluated as per toxicity criteria, was verified as 5,000 mg/kg/day (P<0.05). Similarly, for female rats, a certain minor effect associated with the test substance was observed in 5,000 mg/kg/day dosed group, with no major effect, yet the NOAEL value (as assessed as per toxicity criteria) was determined to be 5,000 mg/kg/day (P<0.05), which was the same as for male rats. Accordingly, the NOAEL values of the test substances for all female and male rats were finally verified as 5,000 mg/kg/day (P<0.05). In conclusion, it was determined that the 23%-GNANA test substance exceeds 2,000 mg/kg/day, the clinical allowance characteristic for functional health food, and was finally evaluated to cause no safety concerns when used as a raw material in functional health food production, which was the ultimate goal of the present study.

• Korean Journal of Soil Science and Fertilizer
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• v.20 no.3
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• pp.209-216
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• 1987

The experiments were carried out in lab. as well as in pots, to develop the agricultural usage of water swellable polymer, a kind of polyacrylic acid(K-sorb) synthesized by the Korea Advanced Institute of Science & Technology (KAIST) recently. The changes of soil physical properties and the influences to crops were investigated with various levels of K-sorb. When the K-sorb mixed with soils and soaked up distilled water, the volume of soils increased with the increase of soil available water contents and increase of K-sorb application levels. The rate increase of soil available water was higher in the coarse textured soils than in the fine while the swelling rate of soil volume showed adverse tendencies. A positive linear regression was observed between the contents of available soil water and levels of K-sorb. K-sorb application decreased bulk density and hardness due to the increase of porosity after soybean cultivation. The permeability in coarser textured soils such as sandy and coarse loamy families was decreased with the increase of K-sorb but in the medium textured soils it was opposite. At higher levels of K-sorb, about 0.5%, the permeability abruptly decreased due to dispersion and vertical movement in silty soils, while it was not changed in fine clayey soils but has the same trend with silty soils. In the plot of 0.3% of K-sorb application, the growth of soybean such as number of pods and stem length etc. increased and the yield also increased about 1.2-1.8 times of control. The optimum amounts of K-sorb were slightly different according to soil texture but estimated from regression curves were about 0.2% to 0.35% of soils in dry weight bases.

• Journal of The Korean Society of Grassland and Forage Science
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• v.1 no.1
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• pp.18-28
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• 1978

To study about the effect of harvested stage and physical treatment such as wilting or chopping of plant material on the quality of silage, Italian ryegrass(Lolium multiflorum) harvested at pre-headed or heading stage and Seombadi(Dystaenia takesimana Nakai) harvested at pre-flowering stage, were used for the purpose. The materials were treated in four different ways which were a) non-treated, b) one day-wilted, c) chopped with 1 to 2cm length and d) wilted and chopped, and those were ensiled in plastic containers and stored at room temperature for three months. After three months of storage, it was investigated and obtained the following results. 1) Having 6.31 of NFE/CP ratio and low content of crude fiber, Seombadi contained more suitable constituents for silage than Italian ryegrass. 2) Under the non-treated or chopped condition, the loss of NFE was higher, and lower with wilted material. 3) Wilting or chopping improved DM digestibility. 4) Compared with Italian ryegrass harvested at pre-headed stage, the storage amount per unit volume of heading stage-Italian ryegrass and Seombadi were higher 8% and 69% respectively, and wilting and/or chopping increased the storage amount 41 to 134%. 5) The majority of weight loss during storage was observed at 1st week after ensiling, it continued slightly until 4th week. The highest loss in 8th week were 3.76% of nontreated material. 6) One day wilting increased DM content of silage 23 to 131%. Wilting and chopping increased pH and lactic acid improved the quality considerably. 7) The correlation between $NH_3$ and butyric acid, and between lactic acid and DM were r=0.782**, r=0.634** respectively. The regression equation were y=12.853X+4.908 (X=butyric acid), y=0.016X+1.309(X=DM content), respectively. 8. The above results indicate that it is necessary to wilt or chop material to make good quality silage from Italian ryegrass, and such treatment can improve the quality of silage with Seombadi also.

• Korean Journal of Food Science and Technology
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• v.45 no.4
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• pp.428-433
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• 2013

Heterogenous samples of locust bean gum (galactomannan) were prepared into homogeneous substances. Locust bean gum was fractioned using ammonium sulfate (14.11-23.08%, w/w). The intrinsic viscosity was obtained by extrapolating reduced viscosity versus concentration by using an Ubbelohde viscometer. The ranges of intrinsic viscosity for fractions that not included protein (F3-F6) and fractions that included protein (F1-F2) were 9.89-8.10 and 8.44-4.59, respectively. Values for Huggins' coefficient (k'), which depends on physical interactions, were 0.46-0.78. Increasing ammonium sulfate concentration was associated with a weak trend towards lower molecular weight and intrinsic viscosity by size-exclusion chromatography (SEC): $M_w$ ranged from 674 to 617 kg/mol and [${\eta}$] from 9.80 to 8.10 dL/g between F3 and F6. The evaluations of those fractions by using SEC and the Ubbelohde viscometer produced very similar values, as predicted. We verified the application of a gradient of ammonium sulfate to precipitate locust bean gum into fractions of different molecular size and show structural variations.

• Journal of Mushroom
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• v.7 no.3
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• pp.115-121
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• 2009

Recently sawdust cultivation of Shiitake mushroom (Lentinula edodes ) is getting increased because log cultivation is getting difficult to get oak logs. It is important to make mycelia browning on the substrate surface in sawdust cultivation. This browned surface plays an important role like as artificial bark of the oak log, which protects the other pests and suppresses water evaporation in the substrate. The period for mycelia browning is so long that the sawdust cultivation of Shiitake mushroom can not spread well into the mushroom farms. In this article we would like to discuss about the effect of environmental condition to the mycelial browning during sawdust bag cultivation for the To reduce the period required for browning of substrates, sawdust substrates was illuminated light with difference intensity. One hundred Lux light illumination was needed for producing normal yield of fruit body but fruit body yield was low and abnormally shaped fruit body was produced when cultured under the dark condition of incubation. Illumination over 200lux is necessary for the successful browning of substrates during incubation. Optimum incubation temperature for browning of substrates and fruiting was $25^{\circ}C$. The treatment of cotton plug with different size to identify the effect of aeration on the browning of substrates and fruiting showed rapid mycelial growth and reduced the periods for browning as the size of cotton plug was bigger. However, yield of fruit body was the highest at 16mm diameter cotton plug as compared to 20mm of that. $CO_2$ content in vessel of substrates was low as the size of cotton plug was bigger during incubation. $CO_2$ content during incubation of substrate was highest in periods between 8 week and 14 week after inoculation of shiitake when substrate was changed color into brown. $C_2H_4$ content in vessel with substrates was highest at 8mm diameter cotton plug and it was increased by order of 12, 16, 20, 0, 4 mm diameter cotton plug during substrate incubation. Sawdust substrate was soaked in cold water for different time to identify soaking effect of sawdust substrate on fruit body yield and activities of enzymes in these substrates were investigated. The fruit body yield was increased up to 40% by soaking substrates in comparison with unsoaked substrates. The soaked substrates showed 165, 175g/1,000ml at treatment of 4 and 15 hours, respectively. Cellulose activities in soaked substrates were not changed with soaking time, but activities of laccase, lignin degradation enzyme, were drastically increased up to 4 times in comparison with unsoaked substrates.

• Horticultural Science & Technology
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• v.33 no.5
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• pp.687-696
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• 2015

Black mini tomato 'Hei-G' fruits were harvested at different stages of maturity (immature-mature green and mature-black red) and stored at different temperatures (8, 12, and $20^{\circ}C$) to investigate the quality and lycopene content during storage. Weight loss increased dramatically at higher temperature for both harvesting stages without significant differences. Firmness of immature fruits decreased below the initial level of mature fruit (8.1N) after 5, 8, and 19 days storage, when they were stored at 20, 12, and $8^{\circ}C$, respectively. Soluble solid contents of mature fruit increased at initial storage, and were higher as compared to immature fruits before deterioration at each storage temperature. Decrease in titratable acid of mature fruits depended on storage time and temperature. However, titratable acid of immature fruits showed little change during storage, and so it did not affect flavor. Hunter a value changed greatly in immature fruit stored at high temperature. Unlike ripe tomatoes, there was no significant difference in black tomato Hunter b values of immature and mature fruit at initial and 12 days storage. However, immature fruits stored at $8^{\circ}C$ did not reach full maturity and color development and ripening. High storage temperature increased lycopene production while low storage temperature blocked lycopene development. Shelf life of the immature fruits, which was evaluated by elapsed days to conventional mature stage, was 12 and 15 days when they were stored at 20 and $12^{\circ}C$, respectively. The optimum storage temperature to maintain the quality and lycopene content of mature fruits was $12^{\circ}C$. Moreover, the shelf life of mature fruits stored at $20^{\circ}C$ could reach up to 5 days.

• Korean Journal of Agricultural Science
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• v.9 no.2
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• pp.546-555
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• 1982

To evaluate the digestibility and absorbability of proteins, and the rates of energy and nitrogen(N) metabolism of the Korean native goats, studies were carried out with open type respiration apparatus based on the nitrogen-carbon method. The results on the nitrogen retention and the metabolic rate of energy, which was obtained with one male (10-month-old) and one female (24-month-old) goats, both weighing ${\simeq}20kg$, are summarized as follows. 1. When the goats were fed ad libitum the medium quality orchard grass hay, they consumed hay about 0.66 to 0.92% of body weight per day. The hay intake was remained the same even when high quality hay was provided. This amount of hay intake was relatively lower than that of dairy goat and sheep. It was believed to be partly due to the change in feeding enviroment. When fed with hay and soybean meal together, the goats ate hay about 1.06% and soybean meal about 0.60% of body weight, corresponding to 1.66% of body weight as fed basis. 2. The $CO_2$ gas produced from the goat in the open type respiration chamber and absorbed with KOH solution was estimated to be 99~117g/day. The difference in feed intake did not influence the $CO_2$ production; however, these seems to be a linea relationship between body weight and $CO_2$ production. 3. When fed orchard grass hay only, the goats showed protein digestibility of 24~41%. The protein digestibility incresed to 58.2% when fed hay and soybean meal together. A negative nitrogen balance(-0.16g N/day) was observed with goats fed 11.53g N originated from 212g hay and 150g soybean meal. Converting that nitrogen ingested to a crude protein, the amount of crude protein intake by the goats per day was 77.9g compared to 40~45g N known to be required in a day by goat weighing 20kg, indicating that the extra protein ingested was metabolized to provide energy. 4. When the male and female goats comsumed 624 kcal gross energy and 824 kcal gross energy by consuming 158g and 213g of hay, respectively, the digestible energy intake was calculated to be 260kcal for the male and 199kcal for the female goat. The daily heat production of male and female goats were 338kcal and 334kcal, respectively, when fed hay only. However, the female goat fed 212g hay and 150g soybean meal produced about 591kcal per day. Consequently, the energy requirment of the Korean native goats weighing ${\simeq}20kg$ was concluded to be $${\geq_-}$$600kcal net energy per day. 5. The fasting heat product ion of a male goat weighing 27.7kg was 412kcal per day when fasted for 2~3 days. When fasted for 3~4 days, the value decresed to 240kcal. The enviromental temperatures during the expreimental period were ranged from 19 to $34.5^{\circ}C$. The goats seemed to be panting when the chamber temperature rose to $32^{\circ}C$ or above. 6. When fed low levels of dietary protein, serum protein levels of the goats were decresed slightly ($${\leq_-}$$10%); however, urea content in the serum was observed to decrese to a great extent (3X).