• Korean Journal of Soil Science and Fertilizer
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• v.24 no.2
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• pp.86-94
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• 1991

Volcanic ash soils were classified as Andepts, a suborder of the Inceptisols in Soil Taxonomy. Increased knowledge on the volcanic ash soils necessitated and facilitated considerable improvement in this system. As a result, the new Order of Andisols was incorporated in the 1990 edition of the Keys to Soil Taxonomy. The central concept of an Andisol is that of a soil developing in volcanic ejecta, and/or in volcaniclastic materials, whose colloidal fractions are dominated by short-range-order minerals or Al-humus complexes. Andic propertis of volcanic ash soil in Cheju Island were investigated. For this study, soils of toposequence distributed along the southern slope of Mt. Halla, and the major soil groups such as dark brown soils, very dark brown soils, black soils, and brown forest soils were collected and analyzed for Al, Fe and Si extracted with solutions of pyrophosphate, dithionite-citrate. and oxalate respectively. Weolpyeong and Yongheung soils developed on the lower elevations contain only small amounts of allophane and Al-and Fe-humus complexes. For other soils, allophane content decrease with elevation and increaes with soil depth,whereas Al-humus complexes increase with elevation and decrease with soil depth. Substantial amount of allophane and ferrihydrite are found in all horizons of Ora and Ara soils developed on 150-300m elevations and of Noro and Jeogag soils developed on cinder cones. In the A horizons of Pyeongdae, Tosan and Heugag soils developed on the higher elevations, Al-humus complexes are dominant form of Al reflecting low pH and high organic matter content. However, lower horizons are dominated by allophane.

• Journal of Korean Society of Forest Science
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• v.90 no.4
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• pp.431-436
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• 2001

The extractable sulfate content and sulfate adsorption capacity in soils of four Pinus densiflora stands were measured to assess the soil acidification sensitivity to acid deposition. The soluble sulfate content in organic horizon which reflects the previous deposition of sulfur oxides was much higher for Namsan and Ulsan than Kanghwa and Hongcheon. In mineral soils, however, the extractable sulfate content was the greatest for Ulsan followed by Kanghwa, Namsan and Hongcheon due to the interactive effect of previous deposition and soil adsorption of sulfate. Adsorption rates of specifically adsorbed sulfate(proportion of insoluble sulfate to total extractable sulfate) for Namsan, Kanghwa and Ulsan affected by acid deposition were 16.6%, 56.8% and 37.4%, respectively, so that the soil in Namsan had the highest acidification sensitivity to acid deposition. For sulfate adsorption isotherm($RE=mX_i-b$), the significantly positive correlations between added sulfate($X_i$) and adsorbed sulfate(RE) were found only in mineral soil(p<0.05) over all regions. The regression coefficient(m) that means soil sulfate adsorption capacity by 0-30cm depth was 0.16, 0.24, 0.25 and 0.32 in $mmol_c\;kg^{-1}$ for Namsan, Kanghwa, Ulsan and Hongcheon, respectively, indicating that soil acidification sensitivity is the highest for Namsan. The added sulfate($X_i$) that could make the adsorbed sulfate(RE) null was 3.81, 2.17, 4.96 and 0.65 in $mmol_c\;kg^{-1}$ for Namsan, Kanghwa, Ulsan and Hongcheon, respectively and the values of former three regions considerably exceeded the realistic sulfate deposition.

• Korean Journal of Medicinal Crop Science
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• v.15 no.4
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• pp.296-303
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• 2007

Acer tegmentosum (Acereaceae) has been used a source of traditional medicines for the treatment of hepatic disorders in Korea. This research was conducted to determine biofunctional activities of A. tegmentosum stem extract and to identify its bioactive components. Methanolic extract from A. tegmentosum stem was partitioned by using organic solvents, including n-hexane, ethyl acetate, n-butanol, and water. Two compounds were isolated by using an ODS column chromatography from ethyl acetate soluble fraction shown to the strongest antioxidant activity ($RC_{50}=3.15\;{\mu}g/m{\ell}$) among the fractions. The isolated compounds were analyzed by $^1H$ and $^{13}C$ NMR, IR, UV/VIS, MS spectrum data and identified as catechin, ${\rho}-Hydroxyphenethyl$ alcohol $1-O-{\beta}-_D-(6'-O-galloyl)-glucopyranoside$. The compounds have shown strong antioxidant activity, with similar activity to BHA ($RC_{50}=2\;{\mu}g/m{\ell}$). Especially, ${\rho}-Hydroxyphenethyl$ alcohol 1-O-{\beta}-_D-(6'-O-galloyl)-glucopyranoside$ was shown strong anti-lipid peroxidative activity. However, the compounds were not shown antimicrobial activities. In antimicrobial activity assays, ethyl acetate soluble fraction was effective to bacterial inhibition, such as Escherichia coli and Klebsiella pneumonia, with minimum inhibitory concentrations in $125\;{\mu}g/m{\ell}$. Otherwise, antifungal activity against Candida albicans was shown in n-hexane soluble fraction exhibiting $63\;{\mu}g/m{\ell}$ of minimum inhibitory concentration. In anticomplementary activity assays, water soluble fraction was the most effective exhibiting 24% inhibitory activity.

• Microbiology and Biotechnology Letters
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• v.7 no.2
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• pp.75-89
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• 1979

One strain of Penicillium sp. (175-66-B), isolated from soil, was able to produce a substance that has a strong inibition activity against the Agkistrodon and Trimeresurus venoms. In this experiment, the chemical and biological properties of the sample were investigated. As an inhibitory substance, it was effective to the proteinase, hemorrhagic and lethal factors of Agkistrodon and Trimeresurus venoms, and also effective to several fractions of the proteinases and hemorrhagic factors of Agkistrodon halys blomhoffi venom. Moreover, in the addition of prednisotone, it was more effective for the cure of the mouse envenomated with the venom amount of two fold of MLD$_{100}$. This substance was very stable to the acid, alkali and heat. Its melting point was high enough to sublime at 222$^{\circ}C$ without any decomposition. This sample was easily dissolved only in hot water, but not in several organic solvents except for a little dissolution in elate. It did not have the chelating activity. It had very strong specificity to the snake venoms. but its activity was depressed by the addition of zinc or cupric salts. This sample had no acute toxicity to the mouse. Its chemical formula was $C_{16}$ $H_{12}$$N_2$ $O_{10}$ with the molecular weight of about 392. It has two epoxy groups and four carboxyl radicals, but amino, nitrite and nitrate radicals, unsaturated bonds and aromatic ring were not detected. Theuchemical configuration of this sample was suggested to be;

• Journal of Korean Society for Atmospheric Environment
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• v.10 no.E
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• pp.311-324
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• 1994

The quantitative knowledge of N $O_{\gamma}$ (＝N $O_{x}$ ＋HN $O_3$＋/PAN＋N $O_3$ ＋$N_2$ $O_{5}$ ＋HN $O_2$＋N $O_3$$^{-10}$ ＋organic nitrates＋......)distribution is essential in tropospheric chemistry, especially, especially that related to understanding the processes leading to ozone production. Ambient concentrations of NO, N $O_2$, HN $O_3$ and PAN as well as total N $O_{\gamma}$ were measured during June and early July 1992 at a rural site(Candor, NC), in the central Piedmont region of NC. The measurements of N $O_{\gamma}$ species were made in an effort to provide a comprehensive understanding of nitrogen chemistry and to investigate the total nitrogen budget at the site. N $O_{\gamma}$, N $O_2$, and NO showed diurnal variations with maxima in the morning. The maximum N $O_{\gamma}$ concentration reached was 14.5 ppbv, and the maximum concentrations of NO and N $O_2$ were 5.4 and 7.8 PPbv, respectively. The mean N $O_{\gamma}$ concentration as found to be 2.88$\pm$1.58 ppbv(n=743). The mean concentrations of NO and N $O_2$, were found to be 0.15 $\pm$ 0.29 ppbv(n＝785) and 1.31 $\pm$ 0.99 ppbv(n＝769). Products of photochemical oxidants, (N <$O_{\gamma}$-N $O_{x}$ ), such as HN $O_3$ and PAN, as well as ozone showed diurnal variation with maxima in the afternoon and minima at night The fractions of individual reactive nitrogen species to total N $O_{\gamma}$ were investigated and contrasted to the results from remote marine site and rural continental sites. N $O_{x}$ was the major species to total N $O_{\gamma}$(45%). NO concentrations appeared to be nearly constant whether the Prevailing winds were from continental areas or from oceanic areas. Linear regression of $O_3$ with (N $O_{\gamma}$- N $O_{x}$ )/N $O_{\gamma}$ (i.e. percent N $O_{x}$ converted to the photochemical products of N $O_{\gamma}$) yielded ( $O_3$) ＝25.8 〔 N $O_{\gamma}$-N $O_{x}$ 〕/(N $O_{\gamma}$) ＋27, ( $r^{2}$＝0.58). The regression intercept is interpreted as the ozone back ground (intercept=27ppbv) and the slope suggests that 8.6 molecules of ozone are formed per molecule of N $O_{x}$ oxidized products (when the average N $O_{\gamma}$ concentration, about 3 ppbv at the site, is used). The N $O_{x}$ N $O_{\gamma}$ ratio was used as an indicator of the chemical age of airmasses and the ratio showed strong positive correlations with HN $O_3$( $r^{2}$=0.58), PAN ( $r^{2}$=0.46) and $O_3$( $r^{2}$=0.62). Larger N $O_{\gamma}$ and N $O_{x}$ N $O_{\gamma}$ ratio were found when winds came from continental sides. It may suggest that synoptic meteorological conditions and transport of N $O_{x}$ are important in the distribution of N $O_{\gamma}$ and its relationship with photochemical oxidants at the site.

• Journal of Korean Society of Forest Science
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• v.89 no.1
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• pp.77-84
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• 2000

In order to understand the chemical binding forms of Cd in terms of its binding strength in wood, the radial distribution of it through dendroanalysis and its different chemical fractions in trunk wood of mature red pine(Pinus densiflora L.) trees grown in a relatively unpolluted area, in Kangwon-Province, were examined. Total Cd concentration in stem wood was determined by dry digestion and $H_2O$ and 0.01 M solutions of citric acid, malic acid, $CaCl_2$, $MgCl_2$, $Na_2EDTA$ were used as extracting solutions for Cd. Extracting efficiencies of applied solutions were expressed as % of Cd concentration extracted by $Na_2EDTA$ which extracted all Cd instead of Cd total concentration. Total concentration of Cd decreased from the innermost rings near pith towards the the outermost rings near cambium. Especially through the transition zone this tendency was observed clearly. $H_2O$ was the least effective extractant of Cd, then extracting efficiency increased in the order $MgCl_2$ < $CaCl_2$ $Na_2EDTA$ (extracted all Cd). According to the radial position, extracting efficiency of Cd was ranging from 7 to 30% by $H_2O$ and even from 60 to 95% by citric acid. The Cd extracting efficiencies of $H_2O$ and organic acids increased continuously from the stem center to outermost annual rings, whereas salts showed somewhat different tendency, suddenly decreasing near the outermost ring. The results are discussed with regard to the different chemical binding forms of Cd and the mobility of Cd in wood and comparable with ones in previous studies on Pinus sylvestris and Quercus patraea. According to the results, usefulness of radial distribution pattern of Cd in pine tree trunks for retrosective biomonitoring is questioned.

• Journal of Mushroom
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• v.18 no.1
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• pp.45-52
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• 2020

Termitomyces albuminosus has been recognized to have the best mushrooms in China, in terms of taste and aroma. The efficacy of these mushrooms has been recorded in the botanical list. However, research on the development of their artificial culture methods is necessary. In this study, we prepared an organic solvent extract and a hot water extract to understand the development of compounds and functional foods with antioxidant and anti-inflammatory activities. The IC₅₀ value of DPPH radical scavenging activity of the hot water extract (TA4) was 1.5 mg/mL and the IC₅₀ value of the MeOH fraction (TA2) was 1.93 mg/mL. The anti-inflammatory activity was investigated by the inhibition of NO production. EtOAc fraction (TA1) is a crude extract, but 79% of NO production was inhibited at 100 ㎍/mL. NO was not produced at 200 ㎍/mL. TA1-5-6, from TA1 inhibited NO production by 15% as compared to the positive control at 15 ㎍/mL, and completely inhibited NO production at 30 ㎍/mL. No cytotoxicity was observed at 50 ㎍/mL. TA2-1-5 from the MeOH fraction (TA2) inhibited more than 75% of NO production at 30 ㎍/mL; cytotoxicity was very low even at 50 ㎍/mL. In conclusion, by selective solvent selection, it was possible to manufacture an extract with no cytotoxicity and excellent biological activities. Furthermore, the extracts showed potential for developing various functional foods and drugs.

• 한국해양학회지
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• v.22 no.3
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• pp.130-142
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• 1987

Sedimentological characteristics of the surface sediments in the southern sea off Cheju Island are described from analyses of bottom sediments. The sediments are subdivided into seven textural classes, muddy sand, slightly gravelly muddy sand, sand, clayey sand, sandy clay, sandymud, silty sand. Sand-size sediments are distributed in the southeastern part and/or around the Island, whereas sandy and muddy sediments are mainly distributed in the central and southern parts of the study area. A small portion of mud patch is located in the southwestern part of the area. According to the textural parameters analysis, sediments in the study area are poorly sorted(av.2.52 ), positive skewed(av.1.61 ), leptokurtic(av.1.74 ), transported by saltation and/or suspension, and roundness of quartz is varied from angular to surrounded, which suggesting that the depositional environment is not simple. The calcium carbonate content is on the average 26.99%, and commonly abundant in sand-size sediments, whereas organic matter content in the bulk sediment is on the average 6.70% and usually dominant in fine-grained sediments.Light minerals consist of quartz(av56.01%),Na-Ca feldspar(av.6.15%),K-feldspar(av.9.22%) and rock fragments(av28.11%).The contect onquartz and K-feldspar increases continuously away from the Cheju Island. As a result of geochemical analysis,concentrations of the elements are as follow:Zn:19.42-43.52 ppm (av.30.67ppm),Mn:50-304 ppm(av139.39ppm),Cr:3.54-10.68ppm(av6.50ppm),Pb:5.52-41.68ppm(av.15.60ppm), Co:7.08-14.68ppm (av.10.78ppm),Ni:19.70-42.42ppm(av.29.57ppm),Cu:3.14-9.12ppm(av.5.14ppm),Fe:0.48-2.08% (av1.22%),Ca:0.32-13.16%(av6.60%),Al:0.06-0.08%(av.0.27%),Mg:0.12-0.76%(av.0.53%)na:0.11-0.51%(av.0.36%) Ag:0.48-4.08ppm(av.1.22ppm).Among these elements,the content of Zn,Cu,Cr,Mn,Fe,Al,Mg,Pb and Na increase toward the southwestern area,while the content of Ca and Ag SHOWS the reversed distribution trend.Such a distribution pattern seems to imply that spatial distrivution of heavy metals is closely related to the variation in grain size. X-ray diffractogram show that the minerals in clay from the southwestern mud patch are illite ,chlorite, kaolinte,feldspar and calcite.The bulk of illite in th mud zone is believed to be originated from Huanghe and Yangytze River.The mud patch in this region contains the diagnostic calcite peak,and the concentration of Ca,ni,Pb,Ag are similar to Huanghe type,which indicates that the greater part of these clay fractions may have been derived from the Huanghe River.

• Journal of Animal Science and Technology
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• v.48 no.5
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• pp.699-708
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• 2006

Ground rice, barley and corn were fed separately to the ruminally cannulated Hanwoo (Korean native cattle) for comparing their in situ and in vitro degradabilities, microbial growth, pH and gas production. It has been found that nearly all the dry matter (DM) and organic matter (OM) in barley and rice disappeared during 24 hr suspension in the rumen, but those in corn were only reduced by around 67%. Water soluble DM and OM fractions(‘a’), ranked from highest to lowest was corn, then rice and finally barley, but the order was reversed for content ‘b’, degradable fraction during time ‘t’. Judging by the degradation parameter of ‘b’ fraction, degradation rates per hour of DM and OM for barley were 38.3% and 37.2% respectively, significantly higher than those for rice (7.7% and 5.6%) and corn (4.1% and 1.3%). In general, results obtained from in vitro degradability of DM and OM were lower than those from in situ trials, but the ranking order of degradability was in agreement between both trials. In particular, ground rice has relatively lower in vitro microbial growth than corn or barley, but exhibited higher gas production. In addition, in vitro microbial growth of ground rice increased with up to 12 hr of incubation period, thereafter experienced a decrease with extended incubation time. pH of in vitro solution of rice decreased following 9 hr of incubation but gas production increased rapidly during the same period. From the results of DM and OM degradabilities and pH changes of in vitro solution with incubation time, it is concluded that rice represents a good source of energy for stability of rumen fermentation.

• Journal of Aquaculture
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• v.20 no.1
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• pp.19-25
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• 2007

For establishing a basal diet for the Pacific bluefin tuna Thunnus orientalis (PBT), feeding stimulants were initially identified by omission test using the synthetic extract of horse mackerel, Trachurus japonicus. Four feeding trials were conducted using juvenile PBT weighing $9.0{\pm}0.91\;g$ (trial 1, 2 and 3) and $1.6{\pm}0.23\;g$ (trial 4), which were originated from an artificial seedling production. The fish fed the casein diet with each test solution were added at the ratio of 100 g casein diet to 100 g jack mackerel muscle. A complete synthetic extract of jack mackerel containing all 3 fractions, amino acid, nucleotide and organic nitrogenous base, exhibited a comparable feeding stimulant activity compared to that of natural extract. The omission of nucleotide or amino acid fraction showed lower feeding activity, but the omission of other nitrogenous fraction maintained a similar feeding stimulant activity compared to that of the synthetic extract (trial 1). Inosine-5' monophosphate $Na_2$ (IMP) was identified as a major constituent for maintaining feeding activity. The mixture of L-alanine, L-glutamic acid, L-histidine, L-lysine, taurine and IMP induced a similar feeding activity compared to that of the synthetic extract (trial 2 and 3). In trial 4, the highest feeding activity was finally obtained in the mixture of L-histidine, L-glutamine and IMP, followed by the synthetic extract, the mixture of L-lysine, L-alanine and IMP, IMP and the mixture of L-histidine, L-glutamic acid, L-lysine and L-alanine. These results revealed that the mixture of L-histidine, L-glutamic acid and IMP for the proper feeding stimulant of PBT in this study.