• 한국환경농학회지
• /
• 제16권2호
• /
• pp.187-192
• /
• 1997

낙동강 수계의 주요 농업지대 소유역에 대한 수질조사 결과를 보면, 용존산소량, 전기전도도, 화학적산소요구량, pH, 중금속함량 등은 대부분 농업용수 기준에 비추어 볼 때 문제되지 않으나, 질소 함량은 전체적으로 농업용수 기준치를 상회하며 이온형태의 인은 특히 여름철에 대부분 지역에서 조류생장 최저 농도인 0.05mg/L 이상으로 측정되었다. 지하수의 경우 전기전도도는 하천수보다 높은 경향이고 질소 함량도 농업용수 기준을 훨씬 상회하였으며 지하수 중의 질산태 질소 함량은 음용수 수질 기준인 10mg/L를 초과하는 곳도 있었다. 지하수 중의 인 함량은 하천수와 비슷한 수준이었다. 중금속은 하천수에서와 마찬가지로 아연을 제외하고 납, 구리, 카드뮴 등은 거의 검출되지 않았다. 이상의 결과를 보면 조사 지역이 농업지대이므로 중금속 등의 요염은 문제되지 않지만 질소와 인에 의한 오염은 하천수와 지하수에서 상당한 수준에 달해 있으며 이러한 질소와 인의 오염은 결국 농경지에서의 화학비료와 퇴비의 시용, 축산폐수나 생활하수의 유입에 의한 것으로 보인다.

• 한국물환경학회지
• /
• 제39권4호
• /
• pp.343-355
• /
• 2023

After the implementation of the total pollution load control system, the effect of improving river water quality by expanding investments in basic environmental facilities, inducing operational efficiency, and reducing the load of various pollutants was clear. However, since the implementation of the system, the management of non-point pollutants has been neglected; management focused on specific substances (biochemical oxygen demand (BOD) and total phosphorus (T-P)) and lacked specific cause analysis and action plans, failed to establish a relationship between water quality and pollution load, failed to reflect stakeholder demands for river water quality management, and failed to apply technical conditions. Therefore, to overcome the limitations raised and achieve a practical and efficient advanced total pollution system, the current system was partially improved and will continue to be improved. This study analyzed the performance and limitations of the total pollution system and introduced recent improvements and the contents that are being improved. The main contents included reducing emissions and reduction monitoring, using water quality tele-monitoring system (TMS) data and self-measurement data, adding population-inducing facilities, and adjusting regional development projects from 20 to 30 multi-family housing units, currentizing each pollutant source according to the roadmap. If the system is improved in a developmental direction and responds to various changes, it will be a more practical and effective policy.

• 한국축산식품학회지
• /
• 제40권6호
• /
• pp.1044-1054
• /
• 2020

This study was performed to investigate the effects of lotus leaf hot water extracts treatment on the quality and stability of eggs using impregnation treatment through ultrasonication during storage. A total of 480 eggs were categorized into four treatment groups (n=30 each)-non-treated (CON), soaked for 30 min in lotus leaf hot water extracts without ultrasonication (T1), sonicated in distilled water (T2), and sonicated in lotus leaf hot water extracts (T3)-and stored for 15 d at 30℃. The egg weight, Haugh unit (HU), egg grade, albumen height, yolk color, eggshell thickness, eggshell breaking strength, and weight loss were measured for egg quality assessment. 2-Thiobarbituric acid reactive substance (TBARS) and volatile basic nitrogen (VBN) contents were measured as stability indicators. Additionally, total phenolic contents (TPC), total flavonoid contents (TFC), and 1,1-diphenyl-2-picrylhydrazyl (DPPH) radical scavenging activity were evaluated. The HU, egg grade, albumen height, and yolk color of T3 were significantly higher than those of CON (p<0.05). No significant differences in eggshell thickness and eggshell breaking strength are observed among the groups. The weight loss of T3 was significantly lower than that of the other groups during storage (p<0.05). The application of lotus leaf hot water extracts also significantly reduced TBARS and VBN (p<0.05). The TPC, TFC, and DPPH radical scavenging activity of T3 were significantly higher than those of the other groups (p<0.05). These results suggest that lotus leaf hot water extracts may be useful as a natural ingredient for improving the quality and stability of eggs during storage.

• Ocean and Polar Research
• /
• 제25권1호
• /
• pp.41-52
• /
• 2003

Sediment trap samples were collected to find out characteristic behaviors of metals in the settling particles by using time-series sediment traps at 678m and 1678m water depths in the Bransfield Strait from December 27th, 1999 to December 26th, 2000. Total mass fluxes at the intermediate water depth (678m water depth) were high in the austral summer and low in the austral winter, whereas at the deep water depth (1678m water depth) they showed high values in both the summer and winter. Total mass fluxes were generally higher in the deep water depth than in the intermediate water depth, which indicates that a substantial amount of sediments are laterally transported by strong currents into the deep basin from the shallow water depths. Aluminium contents also showed large seasonal variations with high values in the winter and low values in the summer. On the contrary, organic carbon contents were high in the summer and low in the winter. Al contents were negatively correlated with organic carbon contents, which may be ascribed that detrital particles are diluted by organic matter produced by phytoplankton in the surface waters. Metals measured in this study exhibited three characteristic behaviors; 1) a positive correlation with Al-Ti, Fe, Mn, V, Co, and Ba, 2) a negative correlation with Al-Cd and Zn, 3) no relationship with Al-Sr, Cu, Cr, Ni. Terrestrial materials may act as a major source fer metals that are positively correlated with Al, and organic matter may be a major source for metals that are negatively correlated with Al. Enrichment factor (EF) of Fe, Mn, Ba, Vi Co, Sr, Cr, and Ni ranged from 0.5 to 1.5, whereas EF of Zn, Cu, and Cd showed much higher values than 1.

• 상하수도학회지
• /
• 제12권3호
• /
• pp.30-40
• /
• 1998

Increasing water consumption produced sludge problems of the water treatment plants. The objective of this study is to investigate aluminium coagulants recovery n acidic and alkaline conditions. Water treatment plant sludge produced in Pusan Metropolitan City were tested for the aluminium extraction process. Experiment samples were obtained in summer from water treatment plants of Deoksan and Myongjang. Aluminium coagulants used in these plants during the test period were polyaluminium chloride(PAC), polyaluminium sulfate organic(PSO), polyaluminium sulfate silicate(PASS). Aluminium contents of water treatment sludge were in the range of 7.2~10.9% of the total solids. The recovery percentages for aluminium and iron by acidic extraction method was evaluated to 88% and 42% respectively. Extracted mass variation for other materials such as iron, manganese, total organic carbon was observed during the extraction operation. Alkaline extraction produced more than two times amount of total organic carbon than that in the acidic extraction process.

• Asian-Australasian Journal of Animal Sciences
• /
• 제9권2호
• /
• pp.123-126
• /
• 1996

Sixteen Harnai males were used to evaluate the influence of varying levels of fourwing saltbush hay on feed and water intakes as well as the blood serum mineral status in a completely randomized design. The animals were grouped randomly into four, with four animals in each. The four groups were randomly allotted low, medium, high and very high levels of saltbush hay supplementation in addition to wheat straw. The animals were given fresh water at free of choice. Weekly body weight was recorded for each individual animal. Blood serum was collected for mineral contents. The experiment lasted for eight weeks. The inclusion of saltbush leaves in the diet showed a non-significant effect on the total dry matter intake. There has been a significant increase in the water intake when very high levels of saltbush were included in the ration. Lower levels showed no effect on the water intake. The animals maintained their body weight from week 1 to week 8. No treatment by weeks interactions on the potassium and sodium levels were detected. However higher levels of saltbush increased significantly the potassium and sodium contents in the serum. Calcium contents were significantly(p<0.01) lowered with the inclusion of saltbush leaves in the diet. Whereas Phosphorous contents showed an increasing(p<0.05) trend with the higher levels of saltbush. No clinical or sub-clinical toxicological symptoms were observed in the sheep with the higher mineral contents.

• 한국식품저장유통학회지
• /
• 제3권2호
• /
• 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.

• KSBB Journal
• /
• 제26권2호
• /
• pp.112-118
• /
• 2011

Contents of amino acids, vitamins, and minerals as well as its antioxidant activitiy of Laminaria japonica water extract have been analyzed for preparation of functional foods and cosmetic products. From the analysis of total amino acids, eighteen kinds of amino acids were found in the water extract of Laminaria japonica. Among total amino acids, the order of contents was glutamic acid (2.07 mg/g), alanine (0.51 mg/g), aspartic acid (0.44 mg/g), glycine (0.34 mg/g), and valine (0.34 mg/g). In case of free amino acids, glutamic acid (0.95 mg/g), prolin (0.54 mg/g), aspartic acid (0.44 mg/g), leucine (0.07 mg/g), and phenylalanine (0.07 mg/g) were dominant compositions. Vitamin E was only detected in water extract of Laminaria japonica. The mineral contents were as follows: K 752.60 mg, Na 259.20 mg, Ca 80.20 mg, P 29.50 mg, and Fe 8.32 mg based on 100 g Laminaria japonica water extract. The nitrite scavenging activity of the extract were gradually increased with the extracts contents to 86.2% at concentration of 100 mg/mL and DPPH radical scavenging activity of the extracts were 86.4% at concentration of 50 mg/mL.

• 한국식품영양학회지
• /
• 제34권2호
• /
• pp.174-180
• /
• 2021

The purpose of this study was to determine the optimum extraction method suitable for the availability of biological activities in unripe apples known to be rich in functional components. Unripe apples 'Hongro' picked on May 28th, 2019 were extracted by various extraction methods (hot water, ethanol, enzymatic pre-treatment, ultrasonic wave, and subcritical water) and their extracts were investigated yield, effective component contents, and antioxidant activities. Overall, the yields by the extraction solvent were higher in water than in organic solvent(ethanol) because water-soluble compounds were eluted from a polar solvent. Total phenol contents of the ultrasonic wave (ethanol) extracts were significantly higher in 6 times than hot water extract. Contents of flavonoid were highest in the ethanol extract at 29.14 mg QE/g. Contents of tannin and ursolic acid were also significantly higher in the ultrasonic wave (ethanol) extract. The DPPH radical and ABTS radical scavenging activities were the strongest in the ultrasonic wave (ethanol) extract. Correlation between effective components and antioxidant activities was high in the total phenol content with ABTS and the ursolic acid content with DPPH (p<0.01). The above results suggested that ultrasonic wave (ethanol) extract of unripe apples has the potential to act as a functional material.

• 한국수산과학회지
• /
• 제43권6호
• /
• pp.654-658
• /
• 2010

The purpose of this study is to establish methods for enhancing the survival and growth of cold-water fish and crustacean larvae based on the nutritional components of zoo and phyto live foods. Rotifers, Brachionus rotundiformis, were cultured with a supplement of freshwater condensed Chlorella vulgaris at $28^{\circ}C$ and enriched with Algamac $2000^{(R)}$ at 16, 20 and $26^{\circ}C$, respectively. Isochrysis galbana, Chaetoceros calcitrans and Chlorella ellipsoidea were centrifuged for component analysis after being cultured for approximately one week with conway medium at $20^{\circ}C$. The crude protein and lipid contents of the rotifers were 58.4% and 10.9%, respectively, before enrichment. After enrichment at each temperature, total protein and essential amino acid contents were increased by reducing the enrichment temperature. However, unsaturated fatty acids and multiple fatty acid index (UI) showed their highest values at $20^{\circ}C$. Mono-unsaturated fatty acid content was highest (72.6%) at $16^{\circ}C$. The total protein contents of C. calcitrans and C. ellipsoidea were higher, 33.0% and 35.2%, respectively, than that of I. galbana, 27.8%. Methionin, leusine and histidine, essential amino acids of C. ellipsoidea, had considerably higher values, 50.2, 287.2 and 68.1 mg/g dry matter, respectively, compared to other microalgae. Total lipids, UI, DHA and n-3 PUFA of I. galbana had higher values, 23.6, 272.0, 12.9% and 45.2%, respectively, than other microalgae. Therefore, for cold-water fish and crustacean larvae that require high n-3 PUFA and DHA contents, enrichment of rotifers is desirable at $20^{\circ}C$. Fish larvae would also need more I. galbana than other microalgae.