Earticle

Levels of quercetin in different parts of onion were investigated using high performance liquid chromatography (HPLC) and liquid chromatography mass spectrometry (LC/MS) suitable for use with functional food material. Two main peaks were observed on HPLC chromatograms from the extracts of the skin, and the outer, middle, and core parts of onion. Using LC/MS, peak 1 was tentatively identified as quercetin monoglucoside at m/z 466.4, and peak 2 as quercetin with [M]+ at m/z 303.3. The levels of quercetin in the skin, and the outer, middle and core parts of the plant were 16.83,2.67,0.95, and 0.35 mg/g, respectively. In the study of 1,1-diphenyl-2-picrylhydrazyl (DPPH) radical scavenging activity, skin, the nonedible part, contained the highest amount of quercetin, compared to the other edible parts, and showed the highest DPPH radical scavenging activity. Levels of quercetin and DPPH radical scavenging activity increased from core to skin. All parts of onion exhibited the strongest antibacterial activity only against Staphylococcus aureus and Vibro parahaemolyticus. Antibacterial activities of onion exhibited that S. aureus was more sensitive than V. parahaemolyticus. Among the four onion extracts, the middle part showed the strongest inhibitory activity against S. aureus but all onion extracts showed similar antibacterial activities against V. parahaemolyticus.

The three flavone glycosides, 4'-O-methylisoscutellarein 7-O-(6'''-O-acetyl)-${\beta}$-D-allopyranosyl(1${\rightarrow}$2)-${\beta}$-D-glucopyranoside (1), isoscutellarein 7-O-(6'''-O-acetyl)-${\beta}$-D-allopyranosyl(1${\rightarrow}$2)-${\beta}$-D-glucopyranoside (3), and isoscutellarein 7-O-${\beta}$-D-allopyranosyl(1${\rightarrow}$2)-${\beta}$-D-glucopyranoside (4) in addition to a flavonol glycoside, kaempferol 3-O-${\beta}$-D-glucopyranoside (astragalin, 2), were isolated from Stachys japonica (Lamiaceae). In cholinesterase inhibition assay, compound 1 significantly inhibited aceylcholinesterase (AChE) and butyrylcholinesterase (BChE) activities ($IC_{50}s$, $39.94{\mu}g/ml$ for AChE and $86.98{\mu}g/ml$ for BChE). The content of isolated compounds were evaluated in this plant extract by HPLC analysis. Our experimental results suggest that the flavonoid glycosides of S. japonica could prevent the memory impairment of Alzheimer's disease.

Brain activation and deactivation induced by N-back working memory tasks and their load effects have been extensively investigated using positron emission tomography (PET) and blood-oxygenation level dependent (BOLD) functional magnetic resonance imaging (fMRI). However, the underlying mechanisms of BOLD fMRI are still not completely understood and PET imaging requires injection of radioactive tracers. In this study, a pseudo-continuous arterial spin labeling (pCASL) perfusion imaging technique was used to quantify cerebral blood flow (CBF), a well understood physiological index reflective of cerebral metabolism, in N-back working memory tasks. Using pCASL, we systematically investigated brain activation and deactivation induced by the N-back working memory tasks and further studied the load effects on brain activity based on quantitative CBF. Our data show increased CBF in the fronto- parietal cortices, thalamus, caudate, and cerebellar regions, and decreased CBF in the posterior cingulate cortex and medial prefrontal cortex, during the working memory tasks. Most of the activated/deactivated brain regions show an approximately linear relationship between CBF and task loads (0, 1, 2 and 3 back), although several regions show non-linear relationships (quadratic and cubic). The CBF-based spatial patterns of brain activation/deactivation and load effects from this study agree well with those obtained from BOLD fMRI and PET techniques. These results demonstrate the feasibility of ASL techniques to quantify human brain activity during high cognitive tasks, suggesting its potential application to assessing the mechanisms of cognitive deficits in neuropsychiatric and neurological disorders.

Caryopteris incana (Verbenaceae) has been used to treat cough, arthritis, and eczema in Oriental medicine. The two fractions ($CHCl_3-$ and BuOH fractions) and the essential oil of the plant material were subjected to the inducible nitric oxide synthase (iNOS) assay. The $IC_{50}$ of the $CHCl_3$ fraction and the essential oil on LPS-induced macrophage RAW 264.7 cells were $16.4{\mu}g/mL$ and $23.08{\mu}g/mL$, respectively. On gas chromatography (GC)-mass spectroscopy (MS) analysis, twenty-five components representing 85.5% amount of total essential oil were identified. On the chromatogram, three main substances, trans-pinocarveol, cis-citral, and pinocarvone, occupied 18.8%, 13.5% and 18.37% of total peak area. Furthermore, by HPLC-UV analysis, six compounds including one iridoid (8-O-acetylharpagide)- and five phenylethanoid glycosides (caryopteroside, acteoside, phlinoside A, 6-O-caffeoylphlinoside, and leucosceptoside A) isolated from the BuOH fraction were quantified. The content of six compounds were shown as the following order: caryopteroside (162.35 mg/g) > 8-O-acetylharpagide (93.28 mg/g) > 6-O-caffeoylphlinoside (28.15 mg/g) > phlinoside (22.60 mg/g) > leucosceptoside A (16.87 mg) > acteoside (7.05 mg/g).

In Korea, the leaves of Sonchus brachyotus (Compositae), an edible mountainous vegetable, are traditionally used to treat hepatitis and hemorrhage and are known to have diuretic action. The aqueous ethanolic extract of this plant was selected in our screening experiment using the peroxynitrite ($ONO_2^-$)-scavenging assay, and the present study was performed to qualitatively and quantitatively identify the active compounds from S. brachyotus and validate the present high-permormance liquid chromatography (HPLC) coupled with ultraviolet absorption detection method based on accuracy, precision and repeatability. Five phenolic substances including the main compound, luteolin $7-O-{\beta}-D$-glucuronopyranoside, as well as chlorogenic acid, luteolin 7-O-rutinoside, luteolin $7-O-{\beta}-D$-glucopyranoside, and luteolin, were found in the aqueous ethanolic extract of S. brachyotus. In the HPLC validation experiment, the linearity of the four compounds was established by $R^2$ values of more than 0.999 within the test ranges, and the recovery rate ranged from 98.2 - 105.3%. Luteolin 7-O-glucuronide was a predominant compound (143 mg/g of extract and 18.3 mg/g of the dry weight of plant material) with a potent peroxynitrite-scavenging effect ($IC_{50}$, $1.02{\pm}0.08{\mu}M$). Luteolin and its three glycosides together with chlorogenic acid were qualitatively and quantitatively determined using an HPLC method validated in the present study.

본 연구에서는 감초성분인 glycyrrhizin, liquiritin, liquiritigenin, isoliquiritigenin의 항균활성을 측정하고, 원산지별 감초 추출물에서 항균활성 성분인 isoliquiritigenin과 liquiritigenin을 정량하여 비교평가하였다. 또한 challenge test를 통하여 가장 뛰어난 항균활성을 나타낸 isoliquiritigenin과 합성 방부제인 메틸 파라벤과의 방부력을 비교하였다. 감초 성분의 항균활성을 disc diffusion assay를 통해 측정한 결과, Liquiritigenin과 isoliquiritigenin이 B. subtilis, P. acnes, E. coli, P. aeruginosa에 대해 저해활성을 보였다. 특히 감초성분 중 큰 항균활성을 나타낸 isoliquiritigenin과 합성 방부제로 사용되는 메틸 파라벤과 프로필 파라벤의 최소저해농도를 비교한 결과 isoliquiritigenin이 강력한 항균활성을 나타내는 것을 확인하였다. HPLC를 통해 원산지별 감초 추출물 isoliquiritigenin과 liquiritigenin을 정량한 결과, 이들의 함량은 한국산 감초가 중국산 감초와 우즈베키스탄산 감초보다 높은 것을 확인하였다. 이를 통해 한국산 감초가 우수한 항균력을 나타내는데 isoliquiritigenin, liquiritigenin 함량이 영향을 미치는 것으로 판단된다. Isoliquiritigenin의 B. subtilis, P. acnes, E. coli, P. aeruginosa에 대한 challenge test를 통해 메틸 파라벤 보다 isoliquiritigenin이 뛰어난 방부력을 나타냄을 확인하였다. 이상의 본 연구 결과로부터 감초 성분의 항균활성을 확인하였고, 원산지별 감초(한국, 중국, 우즈베키스탄) 중 한국 감초가 우수한 항균력을 나타내는데 isoliquiritigenin과 liquiritigenin 함량이 영향을 미치는 것으로 사료된다. 또한 감초 성분 중 가장 우수한 항균활성을 나타낸 isoliquiritigenin은 파라벤류를 대체 할 수 있는 천연 보존제로써 이용 가능성이 있다고 판단된다.

The present study was aimed at investigating the antimicrobial activities of licorice's active ingredients. Four samples of licorice ingredients (glycyrrhizin, liquiritin, liquiritigenin, and isoliquiritigenin) were evaluated for their antimicrobial activities against six skin microorganisms. The bioassay applied for determining the antimicrobial effects employed a disc diffusion assay, the minimum inhibitory concentration, and the challenge test. The ingredients showed antibacterial activities. Especially, isoliquiritigenin has significant antimicrobial activities against two Gram-positive (Bacillus subtilis, Propionobacterium acnes) and two Gramnegative (Escherichia coli, Pseudomonas aeruginosa) bacteria. These samples had much higher antimicrobial activities than synthetic preservatives. Our results reveal that liquiritigenin and isoliquiritigenin could be useful compounds for the development of antibacterial agents for the preservation of cosmetics and foods. The two flavonoids, liquiritigenin and isoliquiritigenin, sourced from Korea, China, Uzbekistan, were quantified using HPLC. The results demonstrated that Korean licorice has two flavonoids (liquiritigenin, isoliquiritigenin) in much higher quantities than was observed in the licorice obtained from the two other countries. Thus, isoliquiritigenin and Korean licorice extract represent new candidates for antimicrobial agents.

폐광산은 방치된 광미 등으로 인하여 주변환경에 복합적인 중금속 오염을 야기한다. 이를 방지하기 위하여 국내에서는 1990년대 중반부터 석회석 등의 안정화제와 복토를 이용한 안정화 공법을 기반으로 토양개량사업이 시행 중이다. 복원된 토양의 상부에서는 작물의 재배로 인해 중금속이 고정된 안정화 층이 지화학적 변화를 겪게 되며 이에 따른 중금속의 용출 및 이동이 가능하므로 토양개량사업을 마친 토양에 대한 질 평가 등의 사후 관리는 반드시 필요하다. 토양의 질 평가를 하기 위해서는 이화학적 분석 또는 생물학적인 분석을 개별적으로 하기보다는 이들을 결합한 종합적인 분석이 필요하며 이를 통해 토양의 생태기능상태(ecological functional state)를 평가할 수 있다. 본 연구에서는 대상시료로 경상북도 봉화군 풍정 광산, 전라남도 광양시 점동 광산, 충청남도 서산시 서성 광산 인근 안정화 처리 토양과 안정화 처리가 되지 않은 오염, 비오염 토양을 선정하였다. 토양의 이화학적 성질인 pH, CEC, LOI와 중금속 농도를 측정하였고, 미생물 효소활성도와 비소환원유전자를 정량하였다. 다변량 통계분석을 바탕으로 모든 데이터를 분석하여 토양 생태기능상태를 평가하였다. 안정화 심도 토양과 상부복토, 하부오염토 간의 상관관계를 확인한 결과, 안정화 심도 토양에서 중금속의 농도가 높게 측정되었다. 그리고 풍정광산에서는 안정화 처리 심도 토양이 하부오염토와 유사한 특성을, 점동, 서성 광산에서는 안정화 심도 토양이 상부복토와 유사한 특성을 나타내었는데 이는 점동, 서성 광산 주변 상부복토의 생태기능상태가 좋지 않을 수 있음을 시사한다.

Heavy metals leaching from closed mines have been causing severe environmental problems in nearby soil ecosystems. Mine reclamation in Korea has been recently implemented based on the heavy metal immobilization (a.k.a., stabilization). Since the immobilization temporarily fixes the heavy metals to the soil matrix, the potential risk of heavy metal leaching still exists. Therefore the appropriate monitoring and the related policies are required to safeguard the soils, where all the cultivations occur. The current monitoring methods are based on either heavy metal concentration or simple toxicity test. Those methods, however, are fragmented and hence it is difficult to evaluate the site in an integrated manner. In this study, as the integrated approach, ecological functional state evaluation with a multivariate statistical tool was employed targeting physiochemical soil properties, heavy metal concentrations, microbial enzymatic activity, and arsenic respiratory reductase gene quantity. Total 60 soil samples obtained from three mines (Pungjeong, Jeomdong, Seosung) were analyzed. As a result, the stabilized layer soil and lower layer soil have shown the similar pattern in Pungjeong mine. In contrast, Jeomdong and Seosung mine have shown the similarity between the stabilized layer soil and the cover layer soil, indicating the possible contamination of the cover layer soil.

나노 기술에 대한 관심이 증가함에 따라 다양한 종류의 나노 물질이 환경 정화 분야에서 활발히 연구되고 있다. 이에 따라 새롭게 개발된 나노 물질의 성능을 쉽고 신속하게 측정할 수 있는 분석법에 대한 요구가 증가하고 있다. 본 연구에서는 토양/지하수 정화 분야에서 활발히 사용되는 나노 영가철의 환원 반응성을 쉽고 신속하게 측정할 수 있는 방법으로써 수정된 인도페놀법을 제시하였다. 인도페놀법에서 한계반응물로 작용하던 암모늄과 과량으로 존재하던 페놀을 치환하여 사용함으로써 페놀류에 대한 정량 분석이 가능하도록 수정하였다. 대상으로 한 나노 영가철에 의한 환원 반응은 4-클로로페놀의 페놀로의 환원과 나이트로벤젠의 아닐린으로의 환원이었으며, 수정된 인도페놀법은 반응생성물인 페놀과 아닐린에 대하여 선택성을 나타내 분석 방법으로 사용이 가능함을 확인하였다. 민감도 향상을 위하여 발색 시약의 농도 및 반응 시간, 시료의 전처리 등의 영향에 대하여 평가하였다. 실제 시료를 대상으로 시험하였을 때, 용존 철 이온에 의한 저해 영향을 확인하여 탄산나트륨 용액 주입의 전처리를 이용하여 해결하였다. 최종적으로 개발된 분석 방법을 이용하여 나노 영가철 및 이중금속 나노영가철의 환원 반응성을 측정하였으며, 결과적으로 환원 반응 속도의 차이뿐 아니라 환원 기작의 차이도 구분할 수 있는 가능성을 보여 주어 나노 영가철의 환원과 관련된 연구 분야에서 유용하게 사용될 수 있을 것으로 사료된다.

Nanoscale zero-valent iron (nZVI) has been effectively applied for environmental remediation due to its ability to reduce various toxic compounds. However, quantification of nZVI reactivity has not yet been standardized. Here, we adapted colorimetric assays for determining reductive activity of nZVIs. A modified indophenol method was suggested to determine reducing activity of nZVI. The method was originally developed to determine aqueous ammonia concentration, but it was further modified to quantify phenol and aniline. The assay focused on analysis of reduction products rather than its mother compounds, which gave more accurate quantification of reductive activity. The suggested color assay showed superior selectivity toward reduction products, phenol or aniline, in the presence of mother compounds, 4-chlorophenol or nitrobenzene. Reaction conditions, such as reagent concentration and reaction time, were optimized to maximize sensitivity. Additionally, pretreatment step using $Na_2CO_3$ was suggested to eliminate the interference of residual iron ions. Monometallic nZVI and bimetallic Ni/Fe were investigated with the reaction. The substrates showed graduated reactivity, and thus, reduction potency and kinetics of different materials and reaction mechanism was distinguished. The colorimetric assay based on modified indophenol reaction can be promises to be a useful and simple tool in various nZVI related research topics.

To find the anti-Alzheimer's activity of Cacalia hastata var. orientalis (Compositae), caffeoylquinic acids were analyzed in this plant by HPLC and the inhibitory activities of the extract on cholinesterases including acetylcholinesterase (AChE) and butyrylcholinesterse (BChE) and peroxynitrite ($ONOO^-$) were assayed. Sum of caffeoylquinic acids in the 80% MeOH extract was quantitatively higher in leaves (35.8% of the extract) than in stems (3.7%). The compound, 3,5-dicaffeoylquinic acid, was contained in the highest amount in the leaf (44.32 mg/g dry weight). The $IC_{50}s$ of the 80% MeOH extract were shown to be $67.45{\mu}g/ml$ for AChE, and $8.59{\mu}g/ml$ (for $ONOO^-$), respectively, suggesting that the leaves would have the anti-Alzheimer's activity due to the high content of caffeoylquinic acids.

Background: Power spectrum analysis method is a powerful noninvasive tool for quantifying autonomic nervous system activity. In this paper, we developed a data acquistion system for estimating the activity of the autonomic nervous system by the analysis of heart rate and respiratory rate variability using power spectrum analysis. Materials and Methods: For the detection of QRS peak and measurement of respiratory rate from patient's ECG, we used low-pass filter and impedence method respectively. This system adopt an isolated power for patient's safety. In this system, two output signnals can be obtained: R-R interval(heart rate) and respiration rate time series. Experimental ranges are 30-240 BPM for ECG and 15-80 BPM for respiration. Results: The system can acquire two signals accurately both in the experimental test using simulator and in real clinical setting. Conclusion: The system developed in this paper if efficient for the acquisition of heart rate and respiration signals. The system will play a role in research area for improving our understanding of the pathophysiologic involvement of the autonomic nervous system in various disease states.