• The Korean Journal of Ecology
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• v.14 no.2
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• pp.121-135
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• 1991

A number of laboratory experimentes have performed to elucidate water-soluble of volatile substances from wormwood plant(artemisia princeps var. orientalis) as growth inhibitor or phytotoxicant. in germination tests with aqueous extracts of leaves, stems and roots of the wormwood plants, most tested species showed that relative germination ratio was inversely proportional to comcentration of the extracats. and seedling elongation and dry weight of the species were heavily inhibited with the extracts, incubated leaves, volatile substances of the leaves and soil underneath wormwood plants. gas Chromatography was employed to find out possible phytotoxic substances or growth inhibitors of wormwood leaves. ten substantes have isolated, and most of them were identified as terpenoids.

• The Korean Journal of Ecology
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• v.11 no.2
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• pp.65-76
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• 1988

A number of laboratory and field experiments have performed with aqueous extracts from fresh leaves, fallen leaves and roots of Pinus rigida in order to investigae the effetct of the pine tree. The results obtained found its inhibitive effect on the germination and growth of tested species. Though relative germination ratio of the species was somewhat lower than the control plot, severe inhibition was observed in relative dry weight ration, These results were more obvious in aqueous extracts than in the case of leachates and similar results were also confirmed by field bioassays on the forest soil of P. rigida. Therefore, to find out the inhibitory sybstancesm 14 different kinds of KDICical substances were isolatd from the leaved of the tree by chromato-graphy and nist if them were confirmed to be phenoic compounds, The growth of lettuce was inhibition was observed in the concentration of less than 5X10-3M soluton. Phenolic compounds are assumed the substance related to the allelopathic effect of P. rigida.

• Journal of Plant Biology
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• v.32 no.2
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• pp.109-119
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• 1989

Adhatoda vasica Nees is a shrubby component of tropical and subtropical vegetation in Pakistan. t harbours relatively few unhealthy associated species in and around its thickets. Aqueous extracts, rain leachates, litter from shoots and soil underneath it invariably reduced germination, early growth, biomass, moisture and chlorophyll contents of Pennisetum americanum, Setaria italica, Zea mays, Brassica campestris and Triticum vulgare in different laboratory expreiments. chromatographic analysis revealed the presence of caffeic, ferulic, vanillic, p-coumaric, p-OH-benzoic, and tannic acids in aqueous extracts. The phytotoxicity was related to the test species used, part assayed and parameter measured. It is suggested that the preclusion of the associated species and the dominance of A. vasica is primarily due to allelopathy. Negative grazing also provides better chances for its establishment.

• Journal of the Korean Society of Clothing and Textiles
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• v.1 no.1
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• pp.31-37
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• 1977

The effects of surfactants and concentration of NaOH in surfactant solution on the removal of free fatty acid soil from cotton fabrics were investigated. Cotton fabrics were soiled with palm itic acid which is the most common fatty acid found in natural oily soil and washed in Lauder-ometer with various types of surfactant with or without NaOH. The rate of soil removal was estimated by analyzing palmitic acid contents in fabric before ar d after washing. Analysis of palmitic contents was made by extracting palmitic acid with azeotropic mixture of alcohol-benzene and the extracts were titrated with standard NaOH solution. It was shown that the types of surfactant are important factor in free fatty acid removal and the efficiency increases in the following order: SLS$90\%$ of initial sorption. In relation to the mechanism of detergency, the suspending and emulsifying power of surfactants were also examined. From the results of this experiments, it could be concluded that the soap formation with alkali and the suspending power of surfactant arc significant factors in free fatty acid soil removal, but the emulsifying power of it is neglizible.

• Korean Journal of Soil Science and Fertilizer
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• v.31 no.2
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• pp.114-119
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• 1998

Intensity and stability of the blue color of phospho-molybdate complex in P analysis are known to be influenced by the matrix, reducing regent and acidity of the extractants. Objective of this research was to compare the efficiency of the color-developing reagents for P concentrations in distilled water and extracts of Lancaster, Mehlich II, and Mehlich III methods. Efficiencies on which to base this study were evaluated by the optimum ranges of P, reproducibility of calibration curve and stability of the developed color. Color-developing reagents employed were ammonium molybdate-1,2,4- aminonaphtholsulfonic acid (ANS), ammonium molybdate-ascorbic acid-bismuth subcarbonate (AB), and ammonium molybdate-ascorbic acid-antimony potassium tartarate (AA). The ANS revealed the lowest sensitivity but the widest ranges for P concentrations in color development. On the other hand, the AA bore the narrowest color-developing ranges and its sensitivity was similar to AB. However, at P concentrations lower than $0.5mg\;L^{-1}$, AA was more sensitive than AB. Based on the data on the ranges of calibration curve, stability of color and reproducibility of analytical data. AA reagent was considered to be suitable for the determination of P in distilled water and AB reagent was practically recommendable for soil P analysis in extracts by Lancaster, Mehlich II, and Mehlich III procedures.

• Journal of the Korean Society of Food Science and Nutrition
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• v.34 no.10
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• pp.1520-1524
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• 2005

Young radishes (YR, yeolmu in Korean) were cultivated in the soil with and without sulfur. Young radish kimchi-general (YR kimchi-G) was prepared with YR commonly cultivated in the soil without sulfur. Young radish kimchl-sulfur (YR kimchi-S) and young radish kimchi-sulfur with lime mortar (YR kimchi-SL) were prepared with the YR cultivated in the soil with sulfur an4 sulfur added lime mortar on it respectively. Antitumor effects of methanol extracts from the YR kimchis were investigated in sarcoma-180 tumor cell transplanted mice. The solid tumor growth was significantly inhibited by the YR kimchi-SL prepared with YR grown in the soil with sulfur (p < 0.05). The treatment of the methanol extracts from YR kimchi-S and -SL increased the glutathione S-transferase activities and glutathione contents in the livers, compared to thlose of YR kimchi-G and the control. One of the antitumor effects by the YR kimchis was due to the increased the glutathione levels and the glutathione S-transferase activity which is phase 2 enzyme. These results also suggested that the antitumor effects of YR kimchi can be enhanced by using YR cultivated differently in the presence of sulfur that can help to produce sulfur-containing compounds in YR.

• Asian Journal of Turfgrass Science
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• v.10 no.3
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• pp.263-270
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• 1996

This experiment was conducted to investigate the loss of various herbicides by means of vola-tility from the turfgrass field and the hare ground with the different soil moisture contents and temperatures. Different herbicides were applied at the rates of 375 g a.i. /l0a of pendimethalin,250 g a.i. /l0a of napropamide, and 96.4 g a.i. /l0a of dicamba with 200 \ulcorner/10a of spray volume in the turfgrass(Zoysia japonica cut off 5cm) grown in pots(265.8 $cm^2$) and bared soil. The pots were placed in the growth chamber with 10,000 lux of light intensity(12h per day) at 25 and 35˚C for 7days. Amberlite XAD polymeric resin(20/50 mesh) was used as sampling media for herbicide airborne residues. Air flow was maintained at 10 \ulcorner /min by vacuum pump regulated with a factory calibrated flow meter. Herbicide airborne residues were extracted from the XAD resin with 300 ml of 1:1 acetone and hexane. The extracts were concentrated by rotary evaporation at 35˚C and dissolved in 1 ml MeCN for HPLC analysis. The airborne losses of the herbicide applied in the turfgrass and bare soil increased as the temperature and soil moisture contents were increased, regardless of the kinds of herbicide. Higher airborne residues was observed in the turfgrass pots than the bare soil pots. Pendimethalin and dicamba with higher vapor pressure gave rise to the increased loss of airborne herbicides, showing that 6.26 and 6.4% of average airborne loss in pendimethalin and dicamba, respectively, compared to 0.56% in napropamide. The amount of airborne losses in turfgrass was highest at one day after application and then a declined trend was observed as the time was prolonged. Key words. Herbicides, Turfgrass field, Bare ground, Volatility.

• Proceedings of the Korean Society of Soil and Groundwater Environment Conference
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• 2003.04a
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• pp.405-408
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• 2003

The soild phase microextraction(SPME)fiber which contains 100${\mu}{\textrm}{m}$ polydimethyl siloxane of a stationary phase was used for the analysis of volatile organic compounds contained in aqueous solution. volatile organic compounds, which were spiked in blank water and extracted by the headspace SPME techique, were analyzed by gas chromatography/flame ionization detector(GC/FID). The optimu condition of SPME fiber is determined that the analytes were extracted for 40min from extracts by using PDAfS100${\mu}{\textrm}{m}$ fiber. This new method could have wide application for the analysis of VOCs in aqueous solution.

• Journal of the Korean Wood Science and Technology
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• v.29 no.3
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• pp.92-98
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• 2001

Allelopathic effects of the cork tree (Phellodendron amurense Rupr.) on several crops and soil miro-organisms were assessed using germination bioassay and antimicrobial assay, and allelochemicals were identified. In a germination bioassay, extract of cork tree inhibited at high concentration on germination of several crop seeds such as cabbage, lettuce, and cucumber. However, aqueous extracts inhibited powerfully growth of test organisms such as Streptococus aureus, S. aureus, S. typhimurium, and E. coli as bacteria, and Candida albicans as yeast, and Botrytis cineria and Alternata alternaria as fungi.. The cork tree extract showed strong antimicrobial activities against isolated soil fungi. The allelochemicals were separated using Silica gel, Sephadex LH-20 gel column chromatography and HPLC. The substances were analyzed by UV spectrometry and EI-mass spectrometry. The active allelochemicals were identified as isoquinoline alkaloids, berberine and palmatine.

• Korean Journal of Soil Science and Fertilizer
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• v.26 no.3
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• pp.189-196
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• 1993

Allelopathic inhibition by substance(s) originated from sicklepod(Cassia tora L.) seed on germination of other plant seeds, was confirmed and used to elucidate general mechanism of allelopathy which was occurred widly in natural and/or agricultural ecosystems. The mechanism was deduced from changes in water contents, ${\alpha}$-amylase activities, protease activities, concentrations of abscisic acid and total phenolic compounds during germination of rice and radish seeds treated with water-soluble extracts of sicklepod seeds. The results obtained were summarized as follows. 1. The % germinations of radish, rice, lettuce, barley seeds were decreased by substances originated from crushed sicklepod seeds. 2. By the treatment of water-soluble extracts of sicklepod seeds, the inhibition of germination of radish seeds was occured with the sequential phenomena of increase of protease activity(synthesis), decrease of water content and increase of total phenolic compounds content. 3. In rice, the inhibition of seed germination by the water-slouble extracts of sicklepod seeds was related to increase of abscisic acid concentration and then decrease of ${\alpha}$-amylase activity(synthesis).