• Journal of Korean Society on Water Environment
• /
• v.27 no.4
• /
• pp.491-498
• /
• 2011

We investigated the ranges of total cellular microcystins content of cyanobacterial blooms collected in Korean lakes and rivers from 2005 to 2009. The amount and composition of microcystins of Korean cyanobacteria varied depending on the sampling water bodies and dominant cyanobacterial genera. Toxic cyanobacterial cell numbers equivalent to $1{\mu}g$ MCYSTs/L using total cellular microcystin content of Korean cyanobacteria were in the range of 2,348 to 66,980,638 cells/mL. Only four samples among forty nine samples showed less cell numbers than current criterion of Harmful Algae Alert System, 5,000 cells/mL indicating current criterion do not reflect properly the microcystins content of Korean cyanobacteria. Anabaena and Aphanizomenon spp. showed three to six times higher cell numbers equivalent to $1{\mu}g$ MCYSTs/L than Microcystis spp. To propose criteria of Harmful Algae Alert System for Korean toxic cyanobacteria, we calculated about 50% selective geometrical means of cyanobacterial cell numbers equivalent to $1{\mu}g$ MCYSTs/L in order of toxic content. The proposed criteria for Microcystis, Oscillatoria, Anabaena, and Aphanizomenon spp., are 10,000, 20,000, 40,000, and 80,000 cells/mL, respectively.

• Journal of The Korean Society of Grassland and Forage Science
• /
• v.41 no.2
• /
• pp.77-83
• /
• 2021

Rye (Secale cereal L.) is the most tolerant to abiotic stress including low temperature, drought, and unfavorable soil conditions among the winter cereals. Rye is the rapid growth of early spring results from increasing areas for the use of the forage and green manure in the middle part of Korea. "Jungmo2509", a rye cultivar was developed by the National Institute of Crop Science (NICS), RDA in 2014. It was developed from a cross between "Olhomil", a self-compatible cultivar, and "Synthetic II", a self-incompatible line. "Jungmo2509" is an erect plant type and of a middle size, with a green leaf color, a yellowish-white colored culm, and a yellowish brown-colored, small-size grain. The heading date of "Jungmo2509" was April 23, which was 5 days later than that of "Gogu", respectively. But "Jungmo2509" showed greater resistance to lodging compared to that of the check cultivar, with similar to winter hardiness, wet injury, and disease resistance. "Jungmo2509" was a higher to than "Gogu" in terms of protein content (9.4% and 8.0%, respectively), total digestible nutrients (TDN) (55.7% and 55%, respectively). The seed productivity of "Jungmo2509" was approximately 2.08 ton 10a-1, which was 11% lower than that of the check. Almost all rye cultivars are out-crossing due to genes controlling incompatibility, but "Jungmo2509" is higher seed fertility (56%) than that of Gogu (0%). it has self-compatible genes. "Jungmo2509" is erect in plant type and resistance for lodging. Therefore, "Jungmo2509" can produce uniform seeds for processed grains of human consumption and utilize them as parents for breeding the rye hybrids with high forage yields.

• Clean Technology
• /
• v.27 no.1
• /
• pp.69-78
• /
• 2021

Vegetable oils, such as palm oil and cashew nut shell liquid (CNSL), are used as major raw materials for bio-diesel in transportation and bio-heavy oil in power generation in South Korea. However, due to the high unsaturation degree caused by hydrocarbon double bonds and a high content of oxygen originating from the presence of carboxylic acid, the range of applications as fuel oil is limited. In this study, hydrotreating to saturate unsaturated hydrocarbons and remove oxygen in mixed bio-oil containing 1/1 v/v% palm oil and CNSL on monometallic catalysts (Ni and Cu) and bimetallic catalysts (Ni-Zn, Ni-Fe, Ni-Cu Ni-Co, Ni-Pd, and Ni-Pt) was perform under mild conditions (T = 250 ~ 400 ℃, P = 5 ~ 80 bar and LHSV = 1 h-1). The addition of noble metals and transition metals to Ni showed synergistic effects to improve both hydrogenation (HYD) and hydrodeoxygenation (HDO) activities. The most promising catalyst was Ni-Cu/��-Al2O3, and in the wide range of the Ni/Cu atomic ratio of 9/1~1/4, the conversion for HYD and HDO reactions of the catalysts were 90-93% and 95-99%, respectively. The tendency to exhibit almost constant reaction activity in these catalysts of different Ni/Cu atomic ratios implies a typical structure-insensitive reaction. The refined bio-oil produced by hydrotreating (HDY and HDO) had significantly lower iodine value, acid value, and kinetic viscosity than the raw bio-oil and the higher heating value (HHV) was increased by about 10%.

• Journal of Naturopathy
• /
• v.11 no.2
• /
• pp.109-115
• /
• 2022

Background: Studies on the existence and activation of antioxidants in the wild Erigeron canadensis are still incomplete. Purposes: The activity of antioxidant substances was studied by extracting E. canadensis with ethyl alcohol. Methods: After washing the wild turfgrass, extraction with ethyl alcohol was used to investigate the activity of antioxidant substances using various analytical instruments. Results: The highest yield ratio of the extract was 49.3%, and it varied according to temperature and ethyl alcohol ratio. The 50:50 of water to ethyl alcohol at 180℃ was the highest yield. 100% survival rate was in the untreated group and 98-100% in the experimental group at 50 ppm or more of the extract. There was no cytotoxicity at almost all concentrations. The extract of 25 ppm was suppressed by 42% in the test group. The extract of 50 ppm reduced the free fatty acid content by 15%. Cell viability was 20% at the extract concentration of 50 ppm and 24% at 100 ppm. At an extract of 500 ppm, the free oxygen scavenging ability using DPPH and ABTs was 90-98%. When the changes in the free radical scavenging activity of DPPH and ABTs were observed in three dimensions, the antioxidant activity tended to increase at 85℃ as the temperature increased. However, at 85~130℃, it showed a rather decreasing tendency as the temperature increased. Conclusions: There were antioxidants in the ethyl alcohol extract of the wild grass, there was almost no cytotoxicity and suppressed NO production, and the scavenging function of free oxygen was also high. These results provide primary data for the various natural healing uses of the extracts of the turfgrass.

• The Korea Journal of Herbology
• /
• v.29 no.3
• /
• pp.35-42
• /
• 2014

Objectives : Since single extract powders was released at 1987, the insurance fee has not been changed, but the price of raw material has been increasing. According to this, Pharmaceutical company couldn't invest on quality of the product, so, the quality of single extracts went down and lost the consumer's trust. We checked the contents of marker ingredients in single extract thereby to recover the reliability of insurance-covered herbal preparations. Methods : we bought total twelve products of eight different single extracts of two main pharmaceutical companies among total 65 kinds of single extract powder stipulated in KHP (The Korean Herbal Pharmacopoeia) monograph III at Jan. 2013. Assays of selected single extract powders are performed by KHP regulation. And we surveyed price fluctuation of relevant herb raw materials from 2005 to 2012. Results : Among twelve products, eight single extract powders were suitable by the KHP regulation. But four products didn't reach the content amount of KHP. Marker contents in the single extracts product of Pueraria Root, Licorice, Peony root and Scutellaria Root of A company were 70%, 1%, 23.7% and 75.1%, respectively. Conclusions : We can acertain whether there's a quality problem in the insurance-covered single extract powders. But, A company is no longer producing these improper single extract powders. As a medicine, single extract powders needs to be strictly quality controlled by the company, and regularly monitored by the KFDA.

• Journal of Nutrition and Health
• /
• v.55 no.3
• /
• pp.330-347
• /
• 2022

Folate, a water-soluble vitamin, acts as a coenzyme for one-carbon metabolism in nucleic acid synthesis and amino acid metabolism. Adequate folate nutritional status during the periconceptional period is known to prevent neural tube defects. In addition, insufficient folate intake is associated with various conditions, such as anemia, hyperhomocysteinemia, cardiovascular disease, cancer, cognitive impairment, and depression. This review discusses the rationale for the revision of the 2020 Korean dietary reference intakes for folate, and suggestions for future revisions. Based on the changes in the standard body weight in 2020, the adequate intake (AI) for infants (5-11 months) and the estimated average requirements (EARs) for 15-18 years of age were revised, but there were no changes in the recommended nutrient intakes (RNIs) and tolerable upper intake levels (ULs) for all age groups. Mean folate intake did not reach RNI in most age groups and was particularly low in women aged 15-29 years, according to the results of the 2016-2018 Korea National Health and Nutrition Examination Survey (KNHANES). The percentages of folate intake to RNI were lower than 60% in pregnant and lactating women, but serum folate concentrations were higher than those in other age groups, presumably due to the use of supplements. Therefore, total folate intake, from both food and supplements, should be evaluated. In addition, the database of folate in raw, cooked, and fortified foods should be further expanded to accurately assess the folate intake of Koreans. Determination of the concentrations of erythrocyte folate and plasma homocysteine as well as serum folate is recommended, and quality control of the analysis is critical.

• Journal of Life Science
• /
• v.32 no.2
• /
• pp.119-124
• /
• 2022

To effectively isolate acetic acid bacteria for producing makgeolli vinegar, various products were researched, and Acetobacter pasteurianus CK-1, a strain that is excellent in acetic acid production, was finally isolated. The optimal growth temperature of the isolated strain was confirmed to be 30℃, and it grew well in the pH range of 5.5~6.5, with optimal growth at pH 6. A. pasteurianus CK-1 had the most active proliferation when the initial ethanol concentration in the medium was 4%, and growth was possible even at an ethanol concentration of 7%. When inoculating the isolated strain into makgeolli to induce acetic acid fermentation, the pH at the beginning of fermentation was 3.54, which was gradually lowered to 2.77 after 18 days of fermentation. The acidity was 0.75% at the beginning of fermentation and gradually started to increase from the 4th day of fermentation. The final acidity at the end of fermentation was 5.54%. In the vinegar fermented by inoculating A. pasteurianus CK-1, acetic acid content was detected to be as high as 3,575.7±48.6 mg%, and the malic acid and citric acid contents were 2,150.8±27.6 and 55.8±3.7 mg%, respectively. Further, it was confirmed that the content and ratio of the organic acids produced significantly differed depending on the type of inoculated bacterial strain. During acetic acid fermentation, the populations of yeast and A. pasteurianus CK-1 were inversely changed. In the initial stage of fermentation, yeast dominated, and after 10 days of fermentation, A. pasteurianus CK-1 slowly proliferated and reached stationary phase.

• KOREAN JOURNAL OF CROP SCIENCE
• /
• v.35 no.3
• /
• pp.224-232
• /
• 1990

This study was conducted to find out the improvement of water-logging injury which is an important factor of yield loss in sesame. Water-logging was treated at 10, 25, 40, 55 and 70 days after emergence for 24, 48 and 72 hours in sesame variety 'Ansanggae'. Some important agronomic characters were investigated after treatment. The important agronomic characters such as plant height, leaf area, dry matter weight, capsule setting stem length, number of capsules per plant, ripenning rate and 1,000 grain weight were most susceptible at 55 days after emergence by the water-logging treatment, and the longer period of water-logging, the more susceptible. Allmost of the useful agronomic characters were able to get over injury of water-logging only within 25days after emergence, but could not get it over since 40days. Grain yield was decreased due to the water-logging treatment by 69 to 86% in 55 days after emergence that is most susceptible stage for water-logging as compared with the untreated control which is 13g per pot, and the longer period of water-logging induced the lower yield. Oil content of grain showed significant decrease only in 55 days after emergence but the composition of fatty acid did not influenced by the water-logging.

• Economic and Environmental Geology
• /
• v.56 no.4
• /
• pp.409-419
• /
• 2023

Acid mine drainage(AMD) treatment is classified as both passive and active treatment. During the treatment, about 5,000 tons of neutralization sludge is generated as a by-product per year in Korea. This study was conducted to evaluate the characteristics of sludge generated from physico·chemical treatment processes as an active treatment from 5 different sources (D, H, S, T, Y) and the possibility of the sludges being recycled. The sludges have a pH range of 5.86 ~ pH 7.89, and a water content range of 51% ~ 82%. Most of particle sizes were less than 25 ㎛. In analysis of inorganic elements, the concentration of Al, Fe, and Mn were between 1,189 mg/kg ~ 129,344 mg/kg, 106,132 mg/kg ~ 338,011 mg/kg, and 3,472 mg/kg ~ 11,743 mg/kg, respectively. The concentration of As and Zn in sludge-T, Cd in sludge-D, Ni in sludge-H, Zn in sludge-S, and Cd in sludge-Y exceeded the soil contamination standards of Korea. The results from 2 separate kinds of leaching test, the Korea Standard Leaching Test(KSLT) and Toxicity Characteristic Leaching Procedure(TCLP), showed that all the sludges met the Korea groundwater standards. From the XRD and SEM-EDS analysis, the peaks of calcite and quartz were found in the sludges. The sludge also had a high proportion of Fe and O, and the majority of the composition was amorphous iron hydroxide.

• Journal of Practical Agriculture & Fisheries Research
• /
• v.4 no.1
• /
• pp.55-64
• /
• 2002

This study was carried out to determine agronomic and genetic characteristics of the production process in tropical yams(Dioscorea alata L.). To make clear the possibility of cultivation of tropical yams in the Suwon area, the growth of the aboveground parts and the enlargement of tuber of Dioscorea alata, were investigated. The aboveground parts of the plants whose sprouted mother tuber were planted in late April were grown slowly until the 70-days after planting and grown rapidly after. From about 50-days after plantation, total length of vines slowly decreased due to the burning of the branch vines of lower modes. With regard to the branching progressed to 4th for the solo yam and to 6th for purple yam. The secondary branches tended to grow better. When the formation of daughter tubers was observed at the 50-days after planting, their enlargement was very slow. The rapid growth of tubers began at the 40-days and continued to the 90-days. General components such as protein, fiber, and lipid were higher in D. opposita rather than in D. alata. Hardness of D. alata was 2696.2 while that of D. opposita was 4946.9. Lightness of D. alata was 73.99, being higher than that of D. opposita.