• Fisheries and Aquatic Sciences
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• 제18권2호
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• pp.123-130
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• 2015

Seaweed Sargassum horneri extracts were obtained using supercritical carbon dioxide ($SC-CO_2$) and different solvents. $SC-CO_2$ was kept at a temperature of $45^{\circ}C$ and pressure of 250 bar. The flow rate of $CO_2$ (27 g/min) was constant during the entire 2-h extraction period, and ethanol was used as a cosolvent. Six different solvents [acetone, hexane, methanol, ethanol, acetone mix methanol (7:3), and hexane mix ethanol (9:1)] were used for extraction and agitated by magnetic stirring (250 rpm) in the dark at $25^{\circ}C$ for 20 h; the ratio of material to solvent was 1:10 (w/v). Antioxidant properties of S. horneri extracted using $SC-CO_2$ with ethanol and different solvents have shown good activity. The highest activity belongs to $SC-CO_2$ with ethanol extracted oil, showing DPPH, ABTS, total phenolic content, and total flavonoid levels of $68.38{\pm}1.21%$, $83.51{\pm}1.25%$, $0.64{\pm}0.02mg/g$, and $5.57{\pm}0.05mg/g$, respectively. The S. horneri extracts showed a significant correlation between the antioxidant activity and phenolic content. Based on these results, the $SC-CO_2$ extract (ethanol) of the seaweed extract from brown seaweed may be a valuable antioxidant source.

• 한국환경농학회지
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• 제39권1호
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• pp.44-49
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• 2020

BACKGROUND: Benzo(a)pyrene is a highly toxic substance which has been listed as a Group I carcinogen by the International Agency for Research on Cancer. There have been numerous studies by researchers worldwide on benzo(a)pyrene. Soxhlet, ultrasound-assisted, and liquid-liquid extractions have been widely used for the analysis of benzo(a)pyrene. However these extraction methods have significant drawbacks, such as long extraction time and large amount of solvent usage. To overcome these disadvantages, we aimed to establish a rapid residual analysis of benzo(a)pyrene content in agricultural products and soil samples. METHODS AND RESULTS: A Quick, Easy, Cheap, Effective, Rugged, and Safe (QuEChERS) method was used as the pretreatment procedure. For rapid residual analysis of benzo(a)pyrene, a modified QuEChERS method were used, and the best codition was demonstrated after various performing instrument analysis. The extraction efficiency of this method was also compared with Soxhlet extraction, the current benzo(a)pyrene extracting method. Although both methods showed high recovery rates, the rapid residual analysis method markedly reduced both the measurement time and solvent usage by approximately 97% and 96%, respectively. CONCLUSION: Based on these results, we suggest the rapid residual analysis method established through this study, faster and more efficient analysis of residual benzo(a)pyrene in major agricultural products such as rice, green and red chili peppers and also soil samples.

• 한국식품영양학회지
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• 제29권2호
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• pp.228-236
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• 2016

본 연구에서는 치아씨의 항산화 활성을 증가시키기 위하여 추출용매 종류와 용매농도, 추출시간과 추출온도를 달리하여 총 폴리페놀 함량과 DPPH 라디칼 소거능을 측정한 후 반응표면분석을 이용하여 최적조건을 수립하였다. 치아씨 추출조건은 에탄올과 메탄올용매 모두에서 추출용매 60%, 추출시간 130분과 추출온도 $20^{\circ}C$에서 총 폴리페놀 871.00mg%($R^2=0.9507$), 557.70mg%($R^2=0.9784$)로 가장 함량이 많았고, DPPH 라디칼 소거능은 72.14%($R^2=0.9675$), 52.79%($R^2=0.9524$)의 항산화력을 보였다. 용매종류에서는 에탄올 추출용매가 메탄올 추출용매보다 같은 조건에서는 월등히 높은 항산화력을 보여 에탄올이 치아씨 추출용매로 더 우수한 용매로 선정되었다. 또한 반응표면분석 결과, 용매추출 조건에서는 에탄올 용매에서는 용매추출 시간이나 온도보다는 용매농도에 가장 큰 영향을 받았고, 메탄올 추출조건에서는 용매추출 시간에서 가장 큰 영향력을 주었다. 반응표면분석 후 용매 농도, 시간과 온도의 최적 추출조건의 범위는 에탄올 추출조건은 에탄올농도 63%, 추출시간 100분과 추출온도 $18^{\circ}C$가 최적조건이고, 메탄올 추출조건에서는 추출농도 65%, 추출시간 120분과 추출온도 $16^{\circ}C$를 보였다.

• Journal of the Korean Wood Science and Technology
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• 제45권6호
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• pp.703-719
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• 2017

Miscanthus had a higher lignin content (19.5 wt%) and carbohydrate (67.6 wt%) than other herbaceous crops, resulting in higher pellet strength and positive effect on combustion. However, miscanthus also contains a high amount of hydrophobic waxes on its outer surface, cuticula, which limits the pellet quality. The glass transition of lignin and cuticula were related to forming inter-particle bonding, which determined mechanical properties of pellet. To determine the effects of surface waxes, both on the pelletizing process and the pellet strength were compared with raw and extracted samples through solvent extraction. In addition, to clarify the relationship between pellet process parameters and bonding mechanisms, the particle size and temperature are varied while maintaining the moisture content of the materials and the die pressure at constant values. Furthermore, kraft lignin was employed to determine the effect of kraft lignin as an additive in the pellets. As results, the removal of cuticula through ethanol extractions improved the mechanical properties of the pellet by the formation of strong inter-particle interactions. Interestingly, the presence of lignin in miscanthus improves its mechanical properties and decreases friction against the inner die at temperatures above the glass transition temperature ($T_g$) of lignin. Consequently, it could found that the use of kraft lignin as an additive in pellet reduced friction in the inner die upon reaching its glass transition temperature.

• 한국의류학회지
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• 제37권3호
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• pp.413-423
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• 2013

Chlorophyll is an abundant pigment found in all green plants, algae, and cyanobacteria. This study uses methanol, acetone and water to extract spinach and mate powders in order to examine the possibility of dyeing animal fibers with chlorophyll without chemical alteration. It was shown that methanol extracts of spinach and mate powders can be effectively used to dye wool and silk fabrics if the extract is mixed with water by methanol:water 65:35 v/v. Compared to methanol extract, the acetone extract showed lower chlorophyll yield and lower dye uptake. Water was not an appropriate solvent for chlorophyll extraction and dyeing. Spinach powder showed a higher dye uptake than mate powder due to the higher chlorophyll content than mate powder. It is possible that the chlorophyll dyeing of wool and silk fabrics is due to the hydrogen bonding between the hydroxy amino acids in fiber and the carbonyl groups of chlorophyll. These carbonyl groups are on the heterocyclic ring and the methyl and ethyl side chains of chlorophyll.

• 한국미생물·생명공학회지
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• 제32권4호
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• pp.352-355
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• 2004

The extracts from 70 different plant natural products were used to investigate the antimicrobial activities against Brachyspira hyodrsenteriae, the causative agent of swine dysentery. Among them, the extracts from Terminalia chehula exhibited the highest antimicrobial activities against B. hyodysenteriae. It showed the antimicrobial activity against B. hyodysensteriae mostly in parts of its shell. Minimum inhibitory concentration (MIC) of the water extracts of T chehula was 12.5 mg/ml. After organic solvent extractions, the ethylacetate extracts exhibited higher antimicrobial activities against B. hyodysenteriae, and their antimicroactivities were similar to that of the tannin. In conclusion, these findings suggest that the extracts from T chebula may be used as animal feed additives for their antimicrobial activities against B. hyodysenteriae.

• Journal of Microbiology and Biotechnology
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• 제5권5호
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• pp.297-301
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• 1995

An anthracycline antibiotic, aclacinomycin A (aclarubicin), was produced from a mutant strain of Streptomyces lavendofoliae. The mutant strain which showed a 4-fold higher productivity of aclacinomycin A compared with the parent strain was also found to produce a significantly higher amount of aclacinomycin A than the reported production strain, Streptomyces galilaeus. The aclacinomycin A was produced up to 125 mg/l using potato starch and soybean meal as carbon and nitrogen sources, respectively, on a 3 liter scale fermentation in a 5 liter jar fermentor. The mutant strain also produced significant amount of aclacinomycins Band Y. Aclacinomycin A was isolated from the culture broth by solvent extractions and further purified by silica gel column chromatography. The yield of aclacinomycin A with over 99$%$ purity was found to be over 60$%$ starting from 3 liters of culture broth.

• 대한화학회지
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• 제56권3호
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• pp.357-362
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• 2012

5-Nonylsalicylaldoxime and salicylaldehyde are two derivatives of phenolic compounds which are very applicable materials in industries. Formerly the formylation of phenolic derivatives were carried out by Rimer-Tiemann method. In this work both of these two materials were synthesized by magnesium meditated formylation technique and their structural characterizations were compared by instrumental analysis technique. In order to achieve a selectively orthoformylated product, the hydroxyl group of nonylphenol (or phenol) was first modified by magnesium methoxide. The nonylphenol magnesium salt was then formylated by paraformaldehyde. The oximation reaction was finally applied to the prepared nonylsalicylaldehyde magnesium salt by liquid extracting via water and acid washing and other extractions. The solvent was finally removed by evaporation under reduced pressure. Some instrumental analysis such as $^1H$-NMR, GC/MS and FT-IR spectra were taken on the product in order to interpret the reaction characterization quantitatively and qualitatively. The formaldehyde and oxime functional groups of two compounds were investigated through $^1H$-NMR and FT-IR spectra and were compared. The yield of methoxilation was very good and the yields of formylation and oximation reactions were about 90%and 85% respectively. The orthoselectivity of formylation reaction were evaluated by comparing of the relevant spectra. The GC/MS spectra also confirmed the obtained results.

• 대한화학회지
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• 제39권4호
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• pp.266-274
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• 1995

12-crown-4, 15-crown-5 및 18-crown-6 에테르들을 리간드로 사용하여 수용액에서 $Eu^{3+}$ 및 $Tb^{3+}$ 이온들을 ethylacetate 혹은 dichloromethane층으로 추출하였다. 이들간에 형성된 착물의 반대이온으로 benzoate 이온을 선택하였다. Benzoate 이온으로부터 란탄족 금속이온으로의 에너지 전달에 의하여 유도되는 형광스펙트럼을 역시 측정하였다. 이 결과를 바탕으로 유기용매층에 추출된 란탄족 금속이온들을 형광분석 방법으로 정량할 수 있었다. 측정된 추출율을 이온-쌍극자 상호작용 함으로써 논하였다.

• 한국식품과학회지
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• 제32권2호
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• pp.323-327
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• 2000

인삼가공제품의 원료로 사용되는 가용성 인삼성분의 신속한 추출방법을 개발하기 위한 기초연구로서, 기존 추출 방법들에 비해 환경친화적이고 경제적인 장점이 알려진 마이크로웨이브(2450MHz)의 추출조건을 조사하였다. 가용성 인삼성분의 추출에서 백미삼 원료의 입자크기는 60 mesh, 시료 대 용매비는 1 : 10(g/mL)이 각각 적당하였고, 마이크로웨이브 에너지는 100 W 이하에서 인삼성분의 추출이 용이하였다. 가용성 성분의 수율은 60% 에탄올을 용매로 하여 5분간 1회 추출시 약 83%, 5회 반복 추출시에는 사포닌 성분을 포함한 대부분의 가용성 성분을 추출할 수 있었다.