• 한국환경농학회지
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• 제23권4호
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• pp.251-257
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• 2004

Analytical methods were developed to determine cyclosulfamuron residues in soil, water, rice grain and straw using high-performance liquid chromatography (HPLC) with ultraviolet absorption detection. In these methods, cyclosulfamuron was extracted with aqueous $Na_2HPO_4$/acetone and acetone/methanol mixture from soil and rice samples respectively. Liquid-liquid partition coupled with ion-associated technique, Florisil column chromatography, and solid-phase extraction (SPE) were used to separate cyclosulfamuron from interfering co-extractives prior to HPLC analysis. For water sample, the residue was enriched in $C_{18}$-SPE cartridge, cleaned up in situ, and directly subjected to HPLC. Reverse-phase HPLC under ion-suppression was successfully applied to determine cyclo-sulfamuron in sample extracts with the detection at its ${\lambda}_{max}$ (254 nm). Recoveries from fortified samples averaged $87.8{\pm}7.1%$ (n=12), $97.3{\pm}7.2%$ (n=12), $90.8{\pm}6.6%$ (n=6), and $78.5{\pm}6.7%$ (n=6) for soil, water, rice grain and straw, respectively. Detection limits of the methods were 0.004 mg/kg, 0.001 mg/L, 0.01 mg/kg and 0.02 mg/kg for soil, water, rice grain and straw samples, respectively.

• 한국환경농학회지
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• 제30권4호
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• pp.432-439
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• 2011

BACKGROUND: An official analytical method was developed to determine etofenprox residues in agricultural commodities using high-performance liquid chromatography (HPLC). METHODS AND RESULTS: The etofenprox residue was extracted with acetone from representative samples of five raw products which comprised rice grain, apple, mandarin, cabbage, and soybean. The extract was then serially purified by liquid-liquid partition and Florisil column chromatography. For rice and soybean samples, acetonitrile/n-hexane partition was additionally coupled to remove nonpolar lipids. Reversed phase HPLC using an octadecylsilyl column was successfully applied to separate etofenprox from co-extractives. Intact etofenprox was sensitively detected by ultraviolet absorption at 225 nm. Recovery experiment at the quantitation limit validated that the proposed method could apparently determine the etofenprox residue at 0.02 mg/kg. Mean recoveries from five crop samples fortified at three levels in triplicate were in the range of 93.6~106.4%. Relative standard deviations of the analytical method were all less than 10%, irrespective of crop types. A selected-ion monitoring LC/mass spectrometry with positive atmospheric-pressure chemical ionization was also provided to confirm the suspected residue. CONCLUSION(s): The proposed method is simple, rapid and sensitive enough to be employed in routine inspection or monitoring of agricultural products for the etofenprox residue.

• 펄프종이기술
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• 제37권5호통권113호
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• pp.50-55
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• 2005

In previous report, we investigated the impact of hexeneuronic acid and some residual extractiveson lignin determination. These non-lignin components severely interfered lignin content determination which also affect on the oxygen delignification comparison between aspen and pine unbleached kraft pulps. Very different pattern was observed whether based on uncorrected conventional kappa number or based on corrected kappa number in oxygen delignification comparison. Lower kappa number aspen pulps showed poor response to oxygen delignification when kappa number was used as lignin determination method but better response with using the acid lignin method. Phenolic hydroxyl group in kraft pulps were also compared based on uncorrected or corrected kappa numberfor lignin content. Based on uncorrected kappa number, lower kappa number oxygen-delignified pulps had lower phenolic hydroxyl group. However, lower kappa number oxygen-delignified pulps showed much higher phenolic hydroxyl group based on the corrected lignin content. For accurate comparison for residual lignin properties from different pulps, lignin determination should be corrected from non-lignin components contribution to lignin.

• 펄프종이기술
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• 제43권1호
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• pp.74-82
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• 2011

The bast fiber of Paper mulberry has been generally used as a fibrous raw material in traditional Hanji-making. Nowadays, its uses is expanded to different special purposes such as paper mulberry yarn, laminated paper, antimicrobial paper depending on its application. Despite the wide array of the use of mulberry fibers, it is still limited due to some difficulties in the automation process of manufacturing works. This study is focused on the analysis of chemical components and morphological properties of paper mulberry bark for the automation of bark peeling process. The bast tissue of paper mulberry was separated in three plies; black outer layer, green inner layer, and white inner layer. The total lignin content, holocelluloses, extractives and ashes, and the anatomical structure of the three layers in mulberry bark tissue were investigated. The analysis showed that the black outer layer is composed of about 50% of total lignin content, whereas the white inner layer is composed of about 90% of holocellulose content.

• 펄프종이기술
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• 제43권1호
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• pp.57-64
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• 2011

The purpose of this research is to investigate the anatomical and chemical properties of arrowroots for the use of paper fibers. The cells consisting of arrowroots showed certain affinities with those in the fibers and vessels of hardwood. Its parenchyma cells showed different shapes with those of hardwood. It was observed that starch was filled in the multi-shape cells. The average width and length of arrowroot fibers were $15.2{\mu}m$ ($11.1-20.3{\mu}m$) and 1.9 mm (1.49 mm-2.31 mm), respectively. In the chemical characteristics of arrowroots, the contents of cold- and hot-water, alcohol-benzene, and alkali extractives were 12-17%, 15.6%, and 38.8%, respectively. Its chemical composition was 61.3% holocellulose, 15.5% lignin and 2.0% ash.

• 펄프종이기술
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• 제42권5호
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• pp.54-61
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• 2010

Antifungal and antioxidative activities of Phellodendron amurense extracts were investigated for use as a natural preservative. After separation of P. amurense into phloem, xylem, leaf and fruit each part was subjected to methanol extraction. Each MeOH extract was further fractionated with several solvents(n-hexane, methylene chloride and ethylacetate). Among the methanol extracts, extracts of phloem and leaf inhibited effectively the growth of mold fungi and rot fungi, respectively. Especially, ethylacetate fraction from phloem showed the highest growth inhibitory effects against fungi tested, such as P. citreonigrum H3, P. toxicarium H4, P. corylophilu H5, A. clavatus, P. osteatus, S. commune, and G. lucidum. The fractions of fruit, which had lower antifungal activities mostly than those of phloem, strongly inhibited rot fungi such as G. lucidum, T. versicolor, and T. palustris. Compared to ferulic acid which is well known antioxidant, ethylacetate fraction of fruit showed high antioxidative activities on concentration of 1 to $100{\mu}g/m{\ell}$ in DPPH radical scavenging activity. As a result, antifungal and antioxidative activities of P. amurense suggest that its extract and fraction have a possibility as conservative of cultural heritage because it might get conservation effects against deteriorating microorganisms of cultural heritage.

• Nutritional Sciences
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• 제9권4호
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• pp.330-334
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• 2006

Chemical composition of the Eucommia ulmoides bark, including extractives, proximate, mineral, fatty acid and monosaccharide compositions, was studied The most abundant mineral was calcium (533.17 mg/l00 g). $\alpha-linolenic$ acid (24.7%) and linoleic acid (24.3%), showed higher contents among the fatty acids. Major monosaccharides of E. ulmoides balk were arabinose (13.94 mg/g), xylose (18.91 mg/g) and glucose (119.7 mg/g). From the bark of E ulmoides, four compounds were isolated and their structures were elucidated as caffeic acid (I), kaempferol (II), quercetin (III) and isoquercitrin (IV) by spectroscopic analysis such as NMR and MS, including cellulose TLC and other chemical evidence such as hydrolyzation and acetylation. The antioxidant activities of four isolated compounds were evaluated by DPPH free radical scavenging, hydroxyl scavenging and reducing power assays. The results indicated that all the isolated compounds showed higher DPPH radical scavenging activity than $\alpha-tocopherol$ and BHT that were used as positive controls and these four compounds exhibited considerable reducing power and hydroxyl radical (OH) scavenging activity. Considering from the results above, it suggests that the E. ulmoides bark is a potential natural source of antioxidant material.

• Journal of the Korean Wood Science and Technology
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• 제47권1호
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• pp.80-89
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• 2019

Pine barks are important biomass resources because they are utilised in the production of pine wood and rosins. However, no chemical study has been conducted on the hydrophilic status of pine barks in Indonesia. This aim of this study is to explore the hydrophilic extracts of the barks from six Pinus species (P. elliotii, P. caribeae, P. oocarpa, P. merkusii P. montezumae, and P. insularis). The hydrophilics of pine barks were analysed using gas chromatography-mass spectrometry. The presence of polyphenol contents in the ethanol extracts obtained from the barks of six Pinus species was determined using the tannin-formaldehyde method, Folin-Cioucalteu assay, and vanillin-HCl assay. The ethanol and hot water soluble extractives derived from inner barks were higher in quantity when compared to those derived from the outer bark samples. The polyphenol measurement showed that the highest value of total phenol content was derived from the outer bark of P. montezumae whereas those of the total phenol and tannin- formaldehyde contents were derived from the inner and outer barks of P. oocarpa. GC-MS analysis revealed that nitrogenous compounds are dominant constituents in the inner and outer barks of the six species, followed by sugars and monophenolics, respectively.

• Journal of the Korean Wood Science and Technology
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• 제31권2호
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• pp.45-51
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• 2003

큰잎자작 변재의 메탄올(methanol, MeOH) 조추출물로부터 silica gel column, CPC 등의 크로마토그라피를 이용하여 4종의 화합물을 단리하였으며, 단리물질에 대한 NMR 등의 기기분석 결과, flavonoid 및 lignan 배당체인 catechin 7-O-𝛽-D-xylopyranoside, lyoniresinol 9'-O-𝛽-D-glucopyranoside, 그리고 diarylheptanoid인 11-oxo-3, 8, 12, 17-tetrahydroxy-9-ene [7, 0]-metacyclophane 및 11-oxo-3, 8, 9, 10, 12, 17-hexahydroxy [7, 0]-metacyclophane으로 각각 동정하였다.

• Journal of the Korean Wood Science and Technology
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• 제34권2호
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• pp.95-100
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• 2006

This study is to isolate bio-active compounds from Alnus firma and evaluate their antioxidant activity. Dried wood powder of A. firma was extracted by organic solvents and fractionated in the sequential extraction steps. The isolated compounds were characterized by EI-MS, $^{13}C-$ and $^1H-NMR$ including COSY, DEFT, HMQC, and HMBC. Antioxidant activities of the isolated compounds were evaluated by DPPH (1,1-diphenyl-2-picrylhydrazyl) free radical scavenging effect. From the wood of A. firma, three kinds of diarylheptanoids, alnusodiol (1), alnusonol (2) and alnusone (3), and gallic acid (4) were isolated. Among these four compounds, compound 1, 2, and 3 are isolated from A. firma for the first time. The antioxidant activity of gallic acid was 93.5% at the concentration of 100 ppm. This compound showed stronger antioxidant activity than those of other isolated compounds and the reference BHT (butylated hydroxytoluene).