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Analytical method of aflatoxins in edible oil and infant-children foods (식용유지와 영유아식품 중 아플라톡신 분석방법)

  • Hu, Soo-Jung;Park, Seung-Young;Kim, Soon-Sun;Lee, Joon-Goo;Song, Ji-Young;Kang, Eun-Gi;Lee, Hyun-Sook;Cho, Dae-Hyun
    • Analytical Science and Technology
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    • v.24 no.2
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    • pp.150-157
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    • 2011
  • Aflatoxins are secondary metabolites of the molds of Aspergillus flavus and Aspergillus parasiticus. They are highly carcinogenic compounds and can affect a wide range of vegetable commodities such as cereals (especially corn), nuts, peanuts, fruits and oil seeds, in the field and during storage. In fact, oilseeds are often stored for weeks in conditions that promote the mould growth, and the possible consequent presence of aflatoxins in oilseeds can lead to their transfer in oil. In addition, aflatoxins can be found as a natural contaminant in multi-cereals and beans making baby food for infants and young-children. The objective of this study was to validate the liquid extraction method or develop an analytical method for edible oil and infant-children foods. Therefore, this study developed condition of extract for aflatoxins ($B_1$, $B_2$, $G_1$ and $G_2$) in edible oil using a high performance liquid chromatography with florescence detector (HPLC/FLD). Aflatoxins were extracted from edible oil samples by means of MSPD (Matrix solid phased dispersion), utilizing $C_{18}$ as dispersing material and purified by using immunoaffinity column. The gression line coefficients were above 0.999. The recoveries for aflatoxins ranged from 85.9 to 93.0%, and relative standard deviations were below 5.7%. The new developed method of aflatoxins effectively enhanced recoveries by using MSPD-Immunoaffinity column compared with liquid extraction. The analytical method for liquid extraction of aflatoxin was appropriate for infant-children food. Reviewing the current method, the recoveries of aflatoxins ($B_1$, $B_2$, $G_1$ and $G_2$) were 89.5~92.3%.

Studies on the Insect Pests of Barley in Korea (한국(韓國)의 보리해충(害虫)에 관(關)한 연구(硏究))

  • Kwon, Yong Jung;An, Seung Lak
    • Current Research on Agriculture and Life Sciences
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    • v.3
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    • pp.129-150
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    • 1985
  • The present investigation was conducted to provide a systematic approach necessary to establish an integrated insect pest management program of barley in Korea. Some ecological surveys on insect pests of barley have been undertaken at the field of Experimental Station, Ky$\check{o}$ngbuk Provincial Office of Rural Development as a fixed point survey area, and at 23 localities for round survey throughout southern and central Korea from 1983 to 1984. Previously known insects injurious to barley in Korea were revised and the population dynamics of 10 dominant harmful species were analyzed according to either 24 localities or 25 cultivars respectively by using several sampling methods of net sweeping, black light traps, yellow water pan traps and visual counting. As the results, a total of 94 species belonging to 77 genera under 32 families are known to be injurious to barley, among them 20 species are newly added here. In the population density level, the dominant species were disclosed as Laodelphax striatellus (43.1 %), Macrosiphum avenae(27.0 %), Rhopalosiphum padi(6.5 %), R. maidis(5.4 %), Psammolettix strialus(2.7 %), Chlorops oryzae(2.2 %), Agromyza albipennis(2.1 %) Phyllotreta nemorum(1.4 %), Chaetoenema cylindrica(1.0 %), Dolycoris baccarum(1.0 %) in order. For the general abundance of major insect pests, it was highest in the cultivar P'aldal whereas lowest in Milyang #22. There were tendencies that Psammotettix striatus, Dolycoris baccarum, Phyllotreta nemorum and Chaetocnema cylindrica represented a maximum increase in the beginning of June, while Chlorops oryzae and Agromyza albipennis showed in the middle of May but aphids were in the end of May. In the dominance of natural enemies, Nabis stenoferus occupied 21.4 % and Propylaea japonica 9.6 %.

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COMPARATIVE STUDIES ON THE EARLY EMBRYONIC DEVELOPMENT AND GROWTH OF MERETRIX LUSORIA AND CYCLINA SINENSIS (대합(Meretrix lusoria)과 가무락(Cyclina sinensis)의 초기발생 및 성장에 관한 비교연구)

  • CHOI Shin Soc
    • Korean Journal of Fisheries and Aquatic Sciences
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    • v.8 no.3
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    • pp.185-195
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    • 1975
  • The comparative studies Were conducted with respect to the artificial spawning early embryonic development, metamorphosis and growth of two species Meretrix lusoria and Cyclina sinensis collected from Inchon, Anmyon island and Buan areas from 1969 to 1974. The highest rate of artificial spawning of M. lusoria, which treated with a dilute ammoniun hydroxide(4/100-5/100N)-seawater solutions, was $25.0-33.3\%$, whereas in C. sinensis the rate of spawning was lower than that of M, lusoria under the similar experimental conditions$(12.5-19.0\%)$. However, the rate of artificial spawning of C. sinensis increased $40\%$ by repeated thermal stimulation. The rate of artificial fertilization of M. lusoria and C. sinensis showed highest value from those individuals which were treated with 1/1000N $NH_4OH$ solution. Their fertilized eggs, then, showed a normal development in the 1/1000N $NH_4OH$ solution. In the early embryonic development of M. lusoria and C. sinensis, the appearance of each of polar body, trochophore and D-shaped veliger were observed around 50min. 5-6 hours, and 23 hours after artificial fertilization respectively. The larval shell lengths of M. lusoria reached to $109,5{\pm}0.7\mu,\;144.6{\pm}1.3\mu$ and $208.0{\pm}0.0\mu$ around, 1, 11 and 20 days, after fertilization respectively. The larval shell lengths of C. sinensis reached to $110.5{\pm}0.6\mu,\;147.8{\pm}1.7\mu,\;and\;235.0{\pm}0.0\mu$ around 1, 10 ana 20 days, after fertilization respectively. The correlations of relative growth rate between the shell length(L) and sell height(H) found by the following simple formula from D-shaped veliger to metamorphosing stage. H=0.77L+6.82 for M. lusoria H=0.75L+8.50 for C. sinensis.

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EFFICIENCY OF ENERGY TRANSFER BY A POPULATION OF THE FARMED PACIFIC OYSTER, CRASSOSTREA GIGAS IN GEOJE-HANSAN BAY (거제${\cdot}$한산만 양식굴 Crassostrea gigas의 에너지 전환 효율)

  • KIM Yong Sool
    • Korean Journal of Fisheries and Aquatic Sciences
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    • v.13 no.4
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    • pp.179-183
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    • 1980
  • The efficiency of energy transfer by a population of the farmed pacific oyster, Crassostrea gigas was studied during culture period of 10 months July 1979-April 1980, in Geoje-Hansan Bay near Chungmu City. Energy use by the farmed oyster population was calculated from estimates of half-a-month unit age specific natural mortality rate and data on growth, gonad output, shell organic matter production and respiration. Total mortality during the culture period was estimated approximate $36\%$ from data on survivor individual number per cluster. Growth may be dual consisted of a curved line during the first half culture period (July-November) and a linear line in the later half period (December-April). The first half growth was approximated by the von Bertalanffy growth model; shell height, $SH=6.33\;(1-e^{0.2421(t+0.54)})$, where t is age in half-a-month unit. In the later half growth period shell height was related to t by SH=4.44+0.14t. Dry meat weight (DW) was related to shell height by log $DW=-2.2907+2.589{\cdot}log\;SH,\;(2, and/or log $DW=-5.8153+7.208{\cdot}log\;SH,\;(5. Size specific gonad output (G) as calculated by condition index of before and after the spawning season, was related to shell height by $G=0.0145+(3.95\times10^{-3}{\times}SH^{2.9861})$. Shell organic matter production (SO) was related to shell height by log $SO=-3.1884+2.527{\cdot}1og\;SH$. Size and temperature specific respiration rate (R) as determined in biotron system with controlled temperature, was related to dry meat weight and temperature (T) by log $R=(0.386T-0.5381)+(0.6409-0.0083T){\cdot}log\;DW$. The energy used in metabolism was calculated from size, temperature specific respiration and data on body composition. The calorie contents of oyster meat were estimated by bomb calorimetry based on nitrogen correction. The assimilation efficiency of the oyster estimated directly by a insoluble crude silicate method gave $55.5\%$. From the information presently available by other workers, the assimilation efficiency ranges between $40\%\;and\;70\%$. Twenty seven point four percent of the filtered food material expressed by energy value for oyster population was estimated to have been rejected as pseudofaeces : $17.2\%$ was passed as faeces; $35.04\%$ was respired and lost as heat; $0.38\%$ was bounded up in shell organics; $2.74\%$ was released as gonad output, $2.06\%$ was fell as meat reducing by mortality. The remaining $15.28\%$ was used as meat production. The net efficiency of energy transfer from assimilation to meat production (yield/assimilation) of a farm population of the oyster was estimated to be $28\%$ during culture period July 1979-April 1980. The gross efficiency of energy transfer from ingestion to meat production (yield/food filtered) is probably between $11\%\;and\;20\%$.

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Breakfast Consumption Pattern, Diet Quality and Health Outcomes in Adults from 2001 National Health and Nutrition Survey (2001년 국민건강영양조사에 나타난 아침식사유형에 따른 식사의 질과 건강상태)

  • Shim, Jae-Eun;Paik, Hee-Young;Moon, Hyun-Kyung
    • Journal of Nutrition and Health
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    • v.40 no.5
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    • pp.451-462
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    • 2007
  • This study was conducted to investigate breakfast consumption pattern in relation to diet quality and health outcomes of Korean adults. Data are from 2001 National Health and Nutrition Survey. Dietary information of 3406 adults aged $30{\sim}49$ years and their socio-demographic characteristics, blood lipid profile, fasting blood glucose, blood pressure, anthropometric measurements were analyzed. According to the breakfast consumption of the subjects, they were classified to breakfast skippers and eaters and the eaters' breakfast staple types were defined as RICE, BREAD, NOODLES, MIXED (mixed types including several grain-based dishes), and OTHERS. The proportions of breakfast consumption patterns were 18.4% for skippers, 71.1% for RICE, 2.6% for BREAD, 1.6% for NOODLES, 4.0% for MIXED, and 2.4% for OTHERS. Breakfast skippers had lower daily nutrients intake than breakfast eaters but their health outcomes did not differ from those of eaters. Instead, men with BREAD pattern had higher blood cholesterol and women in NOODLE pattern had higher blood glucose and lower HDL cholesterol. The BREAD pattern breakfast had higher energy contribution from fat and lower nutrient densities and the subjects in BREAD pattern had higher level of household income. Men's BREAD pattern breakfast consisted more animal products than that of women. There was high probability of undernutrition among women in NOODLE pattern and their mean household income was the lowest. From these results, in Korea, breakfast staple types have different food patterns and there was need for developing healthy food patterns appropriate to each staple type. The breakfast consumption pattern had influences on nutrient adequacy of the diet and health outcomes and seemed to represent socio-economic status. These could be used in doing nutrition education in community.

Dietary assessment according to intake of Korean soup and stew in Korean adults: Based on the 2011~2014 Korea National Health and Nutrition Examination Survey (한국 성인의 국물 음식류 섭취에 따른 식생활 평가 : 2011~2014 국민건강영양조사 자료를 이용하여)

  • Kwon, Yong-Suk;Han, Gyusang
    • Journal of Nutrition and Health
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    • v.49 no.5
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    • pp.335-346
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    • 2016
  • Purpose: This study was conducted to conduct dietary assessment of Korean adults according to intake of Korean soup and stew. Methods: To accomplish this study, 20,926 adults aged 19 yr or higher who participated in the dietary intake survey (24 h recall method) were analyzed from the data of the 2011~2014 Korea National Health and Nutrition Examination Survey (KNHANES). The items included in the soup and stew were guk, tang, jjigae, jijimi, and jeongol. Results: Intakes of soup and stew of subjects were divided into quartiles; intake range by quartile was Q1: < 22.96 g, Q2: 22.96~98.75 g, Q3: 98.75~212.23 g, and Q4: $${\geq_-}212.24g$$. In the case of the Q4 group, male, married, employed, higher educated, and high income subjects showed increased intakes of soup and stew. In addition, sodium intake among nutrient intakes increased from 3,849.04 mg in Q1 group to 5,363.57 mg in Q4 group. Intakes of cereals/grains, potatoes/starches, legumes, seeds/nuts, vegetables, mushrooms, fruits, meat, fishes/shell fishes, milks/dairy products, oils/fats, and seasonings among all foods significantly increased from Q1 group to Q4 group. Lastly, in the multivariable regression analysis, male, higher age, married, eating breakfast, consumption of snacks, prepared meals from home/institution, average eating-out frequency per week, energy consumption, and sodium intake related parameters increased intake of Korean soup and stew. Conclusion: Excessive intake of sodium was related to high blood pressure and metabolic syndrome. Thus, there are needs to improve dietary guidelines and nutrition education for balanced intake of soup and stew.

Assessment of Phytoplankton Viability Along the Salinity Gradient in Seomjin River Estuary, Korea (섬진강 하구역에서 염분구배에 따른 식물플랑크톤 활성도 평가)

  • Lim, Youngkyun;Baek, Seung Ho
    • Journal of the Korean Society of Marine Environment & Safety
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    • v.23 no.5
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    • pp.513-523
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    • 2017
  • We evaluated the viability of phytoplankton along the salinity gradient in the flood and ebb tides of spring tide of February and the ebb tide of neap tide of March 2017 in the Seomjin River Estuary. Additional laboratory experiments were also conducted to determine the reason of the pH changes along the salinity gradient using the field natural sample in February. In field, saltwater was well mixed at downstream vertically and the salinity gradient was horizontally appeared toward upstream of freshwater zone. There were strong negative correlations between salinity and nutrient (nitrate + nitrite R=0.99, p<0.001, and silicate R=0.98, p<0.001), implying that those two nutrients of freshwater origin were gradually diluted with mixing the saltwater. On the other hands, relatively high phosphate concentration was kept in the stations of saltwater over 15 psu, indicating that it was caused by resuspended sediments of Gwangyang Bay and downstream by tidal water mixing.Among phytoplankton community structure in winter, Eucampia zodiacus have occupied to be c.a. 70 % in the most stations. Based on the field survey results for survivability of phytoplankton by phytoPAM instrument, there was positive correlations between salinity and chlorophyll a (R=0.82, p<0.001) and, salinity and active chlorophyll a (R=0.80, p<0.001), implying that the dominant marine diatom species may have significantly damaged in low salinity conditions of upstream. Also, maximum mortality rate of phytoplankton caused by low salinity shock was appered to be 75% in the upstream station. In particular, the pH in spring tides of February had tended to increase with high phytoplankton accmulated stations, suggesting that it was related with absorption of $CO_2$ by the photosynthesis of dominant diatom. In laboratory experiments, phytoplankton mass-mortality caused by low salinity shock was also occurred, which is confirmed with reducing the photosynthetic electron transport activity. Following the phytoplankton mass-mortality, bacteria abundance was significantly increased in 24 hours. As a result, the mass-proliferating bacteria can produce the $CO_2$ in the process of biodegradation of diatoms, which can lead to pH decrease. Therefore, marine phytoplankton species was greatly damaged in freshwater mixing area, depending on along the salinity gradient that was considered to be an important role in elevating and reducing of pH in Seomjin River Estuary.

Solid Phase Synthesis of N-(3-hydroxysulfonyl)-L-homoserine Lactone Derivatives and their Inhibitory Effects on Quorum Sensing Regulation in Vibrio harveyi (고체상 합성법에 의해 합성된 N-(3-hydroxysulfonyl)-L-homoserine Lactone 유사체들의 Vibrio harveyi 쿼럼 센싱에 대한 저해 효과)

  • Kim, Cheol-Jin;Park, Hyung-Yeon;Kim, Jae-Eun;Park, Hee-Jin;Lee, Bon-Su;Choi, Yu-Sang;Lee, Joon-Hee;Yoon, Je-Yong
    • Microbiology and Biotechnology Letters
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    • v.37 no.3
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    • pp.248-257
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    • 2009
  • The inhibitors against Vibrio harveyi quorum sensing (QS) signaling were developed by modifying the molecular structure of the major signal, N-3-hydroxybutanoyl-L-homoserine lactone (3-OH-$C_4$-HSL). A series of structural derivatives, N-(3-hydroxysulfonyl)-L-homoserine lactones (HSHLs) were synthesized by the solid-phase organic synthesis method. The in vivo QS inhibition by these compounds was measured by a bioassay system using the V. harveyi bioluminescence, and all showed significant inhibitory effects. To analyze the interaction between these compounds and LuxN, a 3-OH-$C_4$-HSL receptor protein of V. harveyi, we tentatively determined the putative signal binding domain of LuxN based on the sequence homology with other acyl-HSL binding proteins, and predicted the partial 3-D structure of the putative signal binding domain of LuxN by using ORCHESTRA program, and further estimated the binding poses and energies (docking scores) of 3-OH-$C_4$-HSL and HSHLs within the domain. In comparison of the result from this modeling study with that of in vivo bioassay, we suggest that the in silica interpretation of the interaction between ligands and their receptor proteins can be a valuable way to develop better competitive inhibitors, especially in the case that the structural information of the protein is limited.

Estimation and Methods Estimating Daily Food Consumption of Agrammus agrammus (노래미, Agrammus agrammus의 일간섭식량 추정법과 추정)

  • KIM Chong-Kwan;KANG Yong-Joo
    • Korean Journal of Fisheries and Aquatic Sciences
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    • v.25 no.4
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    • pp.241-250
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    • 1992
  • This study was covered the amount of food consumed per day as well as methods estimating the daily food consumption per fish of Agrammus agrammus in natural population to understand flow of food organisms among trophic levels in bio-community of the coastal waters, Shinsudo, Samchonpo. The estimating formulas were induced from the mathematical models that representing the diurnal fluctuation of the stomach fullness of the fish. The daily food consumption could be estimated by both feeding rates and gastric evacuation rates, but it was more reasonable method that based on gastric evacuation rates than feeding rates. The daily food consumption in wet weight per fish by gastric evacuation rates were 1.9856g/day, 3.4725g/day, 4.4418g/day, 5.8168g/day, and 7.2113g/day in the order of age groups from 0 to 4. The daily rations as percentage of body weight were $9.35\%,\;6.65\%,\;5.76\%,\;4.72\%\;and\;5.31\%$ in the order of ages. The daily food consumption was proportional to the body weight of fish, but the daily food consumption per specific body weight was reciprocal to the body weight. Annual food consumption in wet weight. per fish by gastric evacuation rates were 529.98g from the age of 0.25 to 1.0, 1,269.28g from the age of 1.0 to 2.0, 1,622.76g from the age of 2.0 to 3.0, 2,125.57g from the age of 3.0 to 4.0, 1,316.09g from the age of 4.0 to 4.5 The amount of food consumed per fish during 4.25 years, from the age of 0.25 to 4.5, was 6,863.68g in wet weight. the relationships between the daily food consumption(Dr) by gastric evacuation rates and the total length(L, cm) or the body weight(W, g) were as follows: $$Dr=0.036L^{1.702}$$ $$Dr=0.254W^{0.664}$$

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Morphological Variations in Relation to Geographical Distribution of Pond Smelt, Hypomesus olidus Pallas (한국산 빙어의 지리적 형태변이에 대하여)

  • Ryu Bong Suk;LEE Kyung Ro
    • Korean Journal of Fisheries and Aquatic Sciences
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    • v.14 no.3
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    • pp.179-188
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    • 1981
  • The authors made an investigation concerning the geographical distribution and some major differentiations in morphological characteristics associated with the each habitat, of the pond smelt, Hypomesus olidus, which was introduced into Korea more than 50 years ago. Major characteristics utilized for the comparison study were upper jaw (maxillary), number of fin rays, scale structure, vertebral count, number of pyloric caeca, number of gill rakers, and the relative measurements of these and other internal characters. 1. The main areas of natural distribution are Paro Lake, Soyang Lake, Han River, Euirim Lake, and Ogjeong Lake (or Unam Lake) and the tributaries of these waters. 2. Morphological variations varied when the mean values of measurements from each area were compared with the standard measurement value by mosaic comparison, and in some instances a significant variation was found. 3. The most significant variations were found in the number of fin rays of pectoral and anal fins; the lengths from the tip of snout to the origin of pectoral fin, from snout to ventral fin, and from snout to anal fin, relative to standard body length; eye depth relative to head length; upper jaw: the number of pyloric caeca and the scale structure. Variations, on the other hand, by each habitat were not clear in the numbers of ventral and dorsal fin rays, gill rakers, vertebrae and lateral line scale : and the depth of caudal peduncle and distance from the tip of snout to the origin of dorsal fin relative to standard body length. 4. The scales of pond smelt showed some differences in the shape of scales, the shape and position of the focus and the number of ridges according to the scale positions on the body. No radii were present. The relations between longitudinal and transverse diameters of the scale suggest that the pond smelts of Soyang Lake and Un-am Lake are closely related, and those of Han River and Euirim Lake are also closely related. 5. The geographical variations in morphology of the pond smelt seem to have resulted from the variations in turbidity, water temperature, salinity (rather conductivity) and currents. 6. From the results obtained, it may be concluded that such factors as supramaxillary, relation between scale length and its breadth, number of caudal vertebrae and eye depth relative to head length may be used as the key characters for the classification of geographical varieties of Pond smelt.

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