Ether Layer Research Articles

Prediction of the chemical and thermal shrinkage in a thermoset polymer

A multi-scale model for the response of a bi-material “thermostat”, consisting of a single unidirectional lamina of carbon/epoxy and an uncured layer of neat diglycidyl ether of bisphenol F (DGEBF) with curing agent, diethyltoluenediamine (DETDA), is developed in order to measure thermal strains during a prescribed, but arbitrary thermal history. Molecular modeling simulations provided the elastic modulus, coefficient of thermal expansion, glass transition temperature of DGEBF/DETDA as a function of degree of cure. Cure kinetic properties were determined with differential scanning calorimeter measurements. The model allowed separation of strains due to cure shrinkage and thermal expansion. Combining the molecular modeling predictions, cure kinetic measurements and “thermostat” deflection measurements, the complete polymer shrinkage phenomenon is determined over a prescribed thermal cycle. Furthermore, this work can provide a vehicle to develop cure cycles wherein the difference between instantaneous glass transition temperature and specimen temperature is controlled to provide optimum cure cycles for minimum cure shrinkage.

Fatty acids in female’s gonads of the Red Sea fish Rhabdosargus sarba during the spawning season

Objective: To determine the fatty acids profiles in female fish, Rhabdosargus sarba (R. sarba) from the Red Sea during the spawning season. Methods: Monthly individual R. sarba were obtained from Bangalah market in Jeddah, Red Sea and transported to the laboratory in ice aquarium. The total length, standard length and weight were measured, fishes were dissected. Ovaries were removed, weighed and 10 mL of concentrated hydrochloric acid were added to 10 g of the ovary in a conical flask and immersed in boiling water until the sample was dissolved and the fat was seen to collect on the surface. The conical was cooled and the fat was extracted by shaking with 30 mL of diethyl ether. The extract was bowled after allowing the layers to separate into a weighed flask. The extraction was repeated three times more and distilled off the solvent then the fat dried at 100 °C, cooled and weighed. Then 50 mg of lipid was put in a tube, 5 mL of methanolic sulphuric acid was added and 2 mL of benzene, the tube well closed and placed in water bath at 90 °C for an hour and a half. After cooling, 8 mL water and 5 mL petroleum were added and shaked strongly and the ethereal layer was separated in a dry tube, evaporated to dryness. The fatty acid methyl esters were analyzed by using a Hewlett Packard (HP 6890) chromatography, a split/splitless injector and flame ionization detector. Results: In female R. sarba, a total of 29 fatty acids were detected in ovaries throughout the spawning season. The main fatty acid group in total lipid was saturated fatty acid (SFA, 28.9%), followed by 23.5% of polyunsaturated fatty acids (PUFA) and 12.9% of monounsaturated fatty acids (MUFA). The dominant SFA were palmitic and stearic, the major MUFA were palmitoleic and oleic, and the major PUFA were C18:2 and C22:2. During spawning stages, there were no significant differences in total SFA, MUFA and PUFA. The highest value of SFA was in late spawning (36.78%). However, the highest value of MUFA and PUFA was in spawning (16.70% and 24.96% respectively). During spawning season there were significant differences in total SFA between March (late spawning stage) and December (nearly ripe stage), P<0.05. Conclusions: From the present study it has been shown that 29 fatty acids were detected in ovaries of R. sarba throughout the spawning season. The main fatty acid group in total lipid was SFA followed by PUFA and MUFA. The dominant SFA were palmitic and stearic, the major MUFA were palmitoleic and oleic, and the major PUFA were C18:2 and C22:2. The highest value of SFA was in late spawning. However, the highest value of MUFA and PUFA was in spawning.

Ambient Surface Analysis of Organic Monolayers using Direct Analysis in Real Time Orbitrap Mass Spectrometry

A better characterization of nanometer-thick organic layers (monolayers) as used for engineering surface properties, biosensing, nanomedicine, and smart materials will widen their application. The aim of this study was to develop direct analysis in real time high-resolution mass spectrometry (DART-HRMS) into a new and complementary analytical tool for characterizing organic monolayers. To assess the scope and formulate general interpretation rules, DART-HRMS was used to analyze a diverse set of monolayers having different chemistries (amides, esters, amines, acids, alcohols, alkanes, ethers, thioethers, polymers, sugars) on five different substrates (Si, Si3N4, glass, Al2O3, Au). The substrate did not play a major role except in the case of gold, for which breaking of the weak Au-S bond that tethers the monolayer to the surface, was observed. For monolayers with stronger covalent interfacial bonds, fragmentation around terminal groups was found. For ester and amide-terminated monolayers, in situ hydrolysis during DART resulted in the detection of ions characteristic of the terminal groups (alcohol, amine, carboxylic acid). For ether and thioether-terminated layers, scission of C-O or C-S bonds also led to the release of the terminal part of the monolayer in a predictable manner. Only the spectra of alkane monolayers could not be interpreted. DART-HRMS allowed for the analysis of and distinction between monolayers containing biologically relevant mono or disaccharides. Overall, DART-HRMS is a promising surface analysis technique that combines detailed structural information on nanomaterials and ultrathin films with fast analyses under ambient conditions.

Primary study of skin wound healing in rats for Loropetalum chinens

Cutaneous wound is a common health problem of humans. Loropetalum chinens, a medicinal plant, is widely used to treat wounds among the people. The research aims to observe whether L. chinens can promote the rats' wounds healing process, isolate the extracts primarily and commit the wound healing selection, which provide work basis for wound healing research of L. chinens. First we analyzed the possible components with HC-MS/MS, then committed our wound healing experiments for L. chinens in the rat incision wound model and excision wound model, which are commonly used worldwide. After that, we carried on the preliminary isolation of the L. chinens and we screened the heal-promoting effects of the isolations in incision wound model. L. chinens significantly accelerates the wound healing of rat's skin, shortens the healing period, enhances the healing intensity and promotes the cell proliferation and blood vessels formation around the wounds. The isolations, which are petroleum ether layer, ethyl acetate layer and n-butyl alcohol layer, exert heal-promoting effects. It indicates that the possible morphon that promotes wound healing may exist in these three components, with small polar. L. chinens possesses strong wound healing promoting effects, and the active constituent, with small polar, exists in petroleum ether layer, ethyl acetate layer and n-butyl alcohol layer, and we should focus on these three layers when carrying on further studies.

Development of Fe(III)-containing ether-functionalized imidazolium ionic liquids for aryl Grignard cross-coupling of alkyl halides

A series of Fe(III)-containing imidazolium-based ionic liquids containing ether substituents, including [C3OMim][FeCl4] (1, [C3OMim] = 1-(2-methoxyethyl)-3-methylimidazolium), [C3O i Pim][FeCl4] (2, [C3O i Pim] = 1-isopropyl-3-(2-methoxyethyl) imidazolium), [C3OBim][FeCl4] (3, [C3OBim] = 1-butyl-3-(2-methoxyethyl)imidazolium), [(C3O)2im][FeCl4] (4, [(C3O)2im] = 1,3-bis(2-methoxyethyl)imidazolium), [C3OMim][FeBr4] (5) and [(C3O)2im][FeBr4] (6), were prepared and characterized by elemental analysis, Raman spectroscopy and electrospray ionization mass spectrometry. The catalytic performances of 1–6 and related Fe(III)-based catalysts in the cross-coupling of aryl Grignard reagents with alkyl halides bearing β-hydrogens were studied, revealing that mono(ether) functionality improves the catalytic activity and that bis(ether) functionality improves the reusability. After simply decanting the product contained in the ethereal layer, complex 4, which containing bis(ether)-functionalized imidazolium cation, could be successfully recycled seven times.

Efficient cross-coupling of aryl Grignard reagents with alkyl halides by recyclable ionic iron(iii) complexes bearing a bis(phenol)-functionalized benzimidazolium cation

A novel bis(phenol)-functionalized benzimidazolium salt, 1,3-bis(3,5-di-tert-butyl-2-hydroxybenzyl)benzimidazolium chloride (H3LCl, 1), was designed and used to prepare ionic iron(III) complexes of the type [H3L][FeX4] (X = Cl, 2; X = Br, 3). Both 2 and 3 were characterized by elemental analysis, Raman spectroscopy, electrospray ionization mass spectrometry and X-ray crystallography. The catalytic performances of 2 and 3 in cross-coupling reactions using aryl Grignard reagents with primary and secondary alkyl halides bearing β-hydrogens were studied. This analysis shows that complex 2 has good potential for alkyl chloride-mediated coupling. In comparison, complex 3 showed slightly lower catalytic activity. After decanting the product contained in the ethereal layer, complex 2 could be recycled at least eight times without significant loss of catalytic activity.

The Effect of Organic and Metal Oxide Interfacial layers on the Performance of Inverted Organic Photovoltaics

AbstractWe study the origin of the improvement of the power conversion efficiency (PCE) of inverted organic solar cells when an interfacial insulating organic layer of polyoxyethylene tridecyl ether (PTE) is introduced between the indium tin oxide (ITO) bottom electrode and the TiOx interfacial layer. XPS and UPS measurements are used to investigate the energy level alignment at the interfaces within the ITO/TiOx and ITO/PTE/TiOx structures and to identify any effects due to chemical interaction and interfacial dipoles. Scanning electron microscopy studies show that the surface structure of the TiOx layer is affected, when it is coated on top of the PTE layer. Surface contact angle measurements show that the incorporated interfacial layer of PTE is more hydrophilic than ITO and thus PTE modified TiOx becomes more hydrophilic. This, in combination with the surface gaps of the PTE interfacial layer, is likely to lead to changed wetting and hydrolysis properties of TiOx when coated on ITO/PTE than on ITO alone. The different TiOx layer quality is reflected in improved electron selectivity, leading to enhanced fill factor, reduced parasitic resistance effects and higher power conversion efficiency for inverted solar cells with a PTE interfacial layer between ITO and TiOx.

Selective Catalytic Oxidation of Naphthol to Lawsone on Copper Phthalocyanine

A green chemistry approach is used for the synthesis of copper phthalocyanine (CuPc) and its application for the conversion of 2-naphthol to 2-hydroxy-1,4-naphthoquinone (HNQ, Lawsone) in alkaline aqueous solution using H2O2 as an oxidizing agent. The product obtained was compared with that of authentic sample and was found to be identical. Further the effect of amount of catalyst, amount of NaOH, amount of starting material and amount of H2O2, on the rate of reaction was investigated. The efficiency of The reaction was checked using different solvents, temperature, use of substituted CuPc and other metals phthalocyanines. Keywords: Copper phthalocyanine, 2-naphthol, Oxidation, Lawsone, HNQ, phthalocyanines, ether layer, TLC, aromatic phenyl rings, naphthalene, CuPc, lawsone, byproduct

Surfactant Adsorption at the Surface of Mixed Ionic Liquids and Ionic Liquid Water Mixtures

Surface tensiometry and neutron reflectivity have been used to elucidate the structure of the adsorbed layer of nonionic surfactant tetraethylene glycol tetradecyl ether (C(14)E(4)) at the free surface of the ionic liquids ethylammonium nitrate (EAN) and ethanolammonium nitrate (EtAN) and their binary mixtures with each other and with water. Surface tensions reveal that the critical micelle concentration (cmc) depends strongly on solvent composition. The adsorbed surfactant structure elucidated by neutron reflectivity shows that the level of solvation of the ethylene oxide groups varies for both the pure and mixed solvents. This is attributed to solvent-solvent interactions dominating solvent-surfactant interactions.

An efficient and recyclable iron(III)-containing imidazolium salt catalyst for cross-coupling of aryl Grignard reagents with alkyl halides

1,3-Bis(2,6-diisopropylphenyl)imidazolium chloride, [DIPrim]Cl, was used to produce a novel iron(III)-containing imidazolium salt [DIPrim][FeCl4], which included a N,N-diarylimidazolium cation (R = 2,6-diisopropylphenyl), [DIPrim]+, and tetrachloroferrate(III) anion, [FeCl4]−. This compound was an effective and easy-to-use catalyst for the cross-coupling of aryl Grignard reagents with primary and secondary alkyl halides bearing β-hydrogens. After simply decanting the cross-coupling product in the ether layer, [DIPrim][FeCl4] could be reused in at least four successive runs without significant loss of catalytic activity.

Ionic iron(iii) complexes of bis(phenol)-functionalized imidazolium cations: synthesis, structures and catalysis for aryl Grignard cross-coupling of alkyl halides

A series of bis(phenol)-functionalized imidazolium salts, 1,3-bis(4,6-di-R(1)-2-hydroxybenzyl)-2-R(2)-4,5-di-R(3)-imidazolium chlorides H(3)L(n)Cl (R(1) = (t)Bu, R(2) = R(3) = H, H(3)L(1)Cl, 1; R(1) = CH(3), R(2) = R(3) = H, H(3)L(2)Cl, 2; R(1) = (t)Bu, R(2) = H, R(3) = Cl, H(3)L(3)Cl, 3; R(1) = (t)Bu, R(2) = CH(3), R(3) = H, H(3)L(4)Cl, 4), were used to produce a novel series of ionic iron(III) complexes [H(3)L(n)][FeX(4)] (n = 1, X = Cl, 5; n = 2, X = Cl, 6; n = 3, X = Cl, 7; n = 4, X = Cl, 8; n = 1, X = Br, 9; n = 3, X = Br, 10). All of the complexes were characterized by Raman spectroscopy and electrospray ionization mass spectrometry. Elemental analysis and X-ray crystallography were also used. All of the complexes were non-hygroscopic and air-stable, with five of them existing as solids (5, 7-10) and one as an oil (6) at room temperature. A preliminary catalytic study on the cross-coupling reactions of aryl Grignard reagents with primary and secondary alkyl halides bearing β-hydrogens, revealed that all of the ionic iron(III) complexes exhibited good to excellent catalytic activity. Complexes 5, 6 and 8 exhibited optimal activity, whereas 7, 9 and 10 showed only moderate activity. Furthermore, by simply decanting the cross-coupling product in the ether layer, complexes 5 and 6 could be reused in at least seven successive runs without significant loss in catalytic activity.

The Vitamin K-dependent Carboxylase Generates γ-Carboxylated Glutamates by Using CO2 to Facilitate Glutamate Deprotonation in a Concerted Mechanism That Drives Catalysis

The γ-glutamyl carboxylase converts Glu to carboxylated Glu (Gla) to activate a large number of vitamin K-dependent proteins with diverse functions, and this broad physiological impact makes it critical to understand the mechanism of carboxylation. Gla formation is thought to occur in two independent steps (i.e. Glu deprotonation to form a carbanion that then reacts with CO(2)), based on previous studies showing unresponsiveness of Glu deprotonation to CO(2). However, our recent studies on the kinetic properties of a variant enzyme (H160A) showing impaired Glu deprotonation prompted a reevaluation of this model. Glu deprotonation monitored by tritium release from the glutamyl γ-carbon was dependent upon CO(2), and a proportional increase in both tritium release and Gla formation occurred over a range of CO(2) concentrations. This discrepancy with the earlier studies using microsomes is probably due to the known accessibility of microsomal carboxylase to water, which reprotonates the carbanion. In contrast, tritium incorporation experiments with purified carboxylase showed very little carbanion reprotonation and consequently revealed the dependence of Glu deprotonation on CO(2). Cyanide stimulated Glu deprotonation and carbanion reprotonation to the same extent in wild type enzyme but not in the H160A variant. Glu deprotonation that depends upon CO(2) but that also occurs when water or cyanide are present strongly suggests a concerted mechanism facilitated by His-160 in which an electrophile accepts the negative charge on the developing carbanion. This revised mechanism provides important insight into how the carboxylase catalyzes the reaction by avoiding the formation of a high energy discrete carbanion.

담배연기응축물로 유도된 돌연변이와 구절초 추출물의 억제 효과

This study was carried out to investigate whether Chrysanthermum zawadskii var. latilobum Kitamura (C. zawadskii) extracts has an inhibitory effect against the mutagenicity by cigarette smoke condensates (CSC). C. zawadskii was extracted with 70% ethanol and the yield was 18.5%. We further fractioned 70% ethanol extract sequentially to diethylether, chloroform, dichloromethane, and aqueous water, and gained the yield of 17.5%, 5.6%, 5.8%, 32.8% and 35.5%, respectively. In the Ames test, there was no mutagenic effect of crude extract and its solvent fractions up to 2㎎/plate toward Salmonella typhimurium TA 98 with or without S-9 mix metabolic activations. On the contrary, the crude extract showed an inhibitory activity against the mutagenicity of CSC in the presence of S-9 mix metabolic activation. Diethyl ether layer among five solvent fractions showed the highest inhibitory activity. The inhibitory activity of diethyl ether fraction was also increased in a dose-dependent manner and the inhibitory rate was about 97.7% at the concentration of 1㎎/plate. In this study, we conclude that crude extract of C. zawadskii itself is potentially safe for mutagenicity, and the diethyl ether fraction has an inhibitory effect against the mutagenicity of CSC.

Determination of thebaine in water samples, biological fluids, poppy capsule, and narcotic drugs, using electromembrane extraction followed by high-performance liquid chromatography analysis

Opium determination is of great importance from toxicological and pharmaceutical standpoints. In present work, electromembrane extraction (EME) coupled with high-performance liquid chromatography (HPLC) and ultraviolet (UV) detection was developed for determination of thebaine as a natural alkaloid, in different matrices containing water, urine, poppy capsule, street heroine, and codeine tablet. Thebaine migrated from 3 mL of sample solutions, through a thin layer of 2-nitrophenyl octyl ether (NPOE) immobilized in the pores of a porous hollow fiber, and into a 15 μL acidic aqueous acceptor solution present inside the lumen of the fiber. The variables of interest, such as chemical composition of the organic liquid membrane, stirring speed, extraction time and voltage, pH of donor and acceptor phases and salt effect in the EME process were optimized. Under optimal conditions, thebaine was effectively extracted from different matrices with recoveries in the range of 45–55%, which corresponded to preconcentration factors in the range of 90–110. Good linearity was achieved for calibration curves with a coefficient of estimation higher than 0.997. Detection limits and intra-day precision ( n = 3) were less than 15 μg L −1 and 8.9%, respectively.

Electrokinetic extraction on artificial liquid membranes of amphetamine-type stimulants from urine samples followed by high performance liquid chromatography analysis

Electromembrane extraction (EME) coupled with high performance liquid chromatography and ultraviolet detection was developed for determination of amphetamine-type stimulants in human urine samples. Amphetamines migrated from 3 mL of different human urine matrices, through a thin layer of 2-nitrophenyl octyl ether (NPOE) containing 15% tris-(2-ethylhexyl) phosphate (TEHP) immobilized in the pores of a porous hollow fiber, and into a 15 μL acidic aqueous acceptor solution present inside the lumen of the fiber. Equilibrium extraction conditions were obtained after 7 min of operation. Experimental design and response surface methodology (RSM) were used for optimization of EME parameters. Under optimal conditions, amphetamines were effectively extracted with recoveries in the range of 54–70%, which corresponded to preconcentration factors in the range of 108–140. The calibration curves were investigated in the range of 0–7 μg mL −1 and good linearity was achieved with a coefficient of estimation better than 0.991. Detection limits and inter-day precision ( n = 3) were less than 0.01 μg mL −1 and 11.2%, respectively.

Electromembrane extraction of levamisole from human biological fluids

Electromembrane extraction coupled with high-performance liquid chromatography (HPLC) and ultraviolet (UV) detection was developed for the determination of levamisole in some human biological fluids. Levamisole migrated from 4 mL of different acidized biological matrices, through a thin layer of 2-nitrophenyl octyl ether containing 5% tris-(2-ethylhexyl) phosphate immobilized in the pores of a porous hollow fiber, into a 20-μL acidic aqueous acceptor solution present inside the lumen of the fiber. The parameters influencing electromigration were investigated and optimized. Within 15 min of operation at 200 V, levamisole was extracted from different biological fluid samples with recoveries in the range of 59-65%, which corresponded to preconcentration factors in the range of 118-130. The calibration curves showed linearity in the range of 0.5-10, 0.2-10 and 0.1-10 μg/mL for plasma, urine and saliva, respectively. Limits of detection of 0.1, 0.07 and 0.05 μg/mL and limits of quantification of 0.5, 0.2 and 0.1 μg/mL were obtained for plasma, urine and saliva, respectively. The relative standard deviations of the analysis were found to be in the range of 5.6-9.7% (n = 3). Electromembrane extraction was successfully processed for determination of levamisole in plasma, urine and saliva samples.

땅콩나물 추출물의 신경세포 보호 효과

본 연구는 땅콩나물 추출물이 glutamate가 유도하는 세포독성으로부터 신경세포를 보호하는 효과를 확인하였다. 땅콩나물을 부위별로 전체, 머리, 줄기 부분으로 나누어 methanol로 처리하여 얻어진 각각의 추출물 WME, HME 그리고 SME를 이용하여 glutamate에 의하여 유도된 세포독성에 대한 신경세포보호효과를 관찰하였다. 기지의 신경세포 N18-RE-105 세포주를 이용하여 MTT reduction assay, LDH release assay, 형태학적인 변화 및 apoptosis를 관찰한 결과로부터 HME에서 효율적인 신경세포보호효과를 보였다. 다음으로 HME를 이용하여 hexane, diethyl ether, ethyl acetate, water 층으로 분획하여 신경세포 보호 효과를 확인한 결과, diethyl ether 층에서 가장 높은 활성을 확인할 수 있었다. 그리고 HME의 apoptosis 억제 효과를 확인하기 위하여 flow cytometric analysis를 실시한 결과에서 glutamate 만을 처리하였을 경우 sub-G1기 세포가 58.5%의 확인되었으나 HME를 100 mg/ml 동시 처리하였을 때에는 sub-G1 세포가 9.1%로 감소하여 높은 apoptosis 억제 효과를 확인할 수 있었다. 이상의 결과로부터 땅콩나물 머리 부분 methanol 추출물에는 glutamate에 의한 세포독성으로부터 신경세포를 보호하는 효과가 있다는 것을 알 수 있었다. The neuroprotective effects of extracts from various parts of peanut sprouts on glutamate-induced neurotoxicity in N18-RE-105 cells were investigated. This study was performed to evaluate the neuroprotective activity of methanolic extracts from the whole (WME), heads (HME), and stems (SME) of peanut sprouts. The neuroprotective effects of these extracts were measured by MTT reduction assay, LDH release assay, phase-contrast microscopy, and flow cytometric analysis on the N18-RE-105 cells. Among these extracts, the HME showed the greatest neuroprotective effects, and was further fractionated with hexane, diethyl ether, ethyl acetate, and water, according to degree of polarity. Out of the fractionated extracts, the diethyl ether layer showed the highest activity on glutamate-induced cytotoxicity in N18-RE-105 cells. The sub-G1 DNA contents of the glutamate-induced severely apoptotic N18-RE-105s were measured by flow cytometric analysis to confirm the HME's anti-apoptotic activity. Interestingly, after incubation with 100 mg/ml of the HME, the proportion of sub-G1 cells of the glutamate-stressed N18-RE-105s had been greatly reduced, from 58.5% to 9.1%. These results imply that HME may have strong potential as a chemotherapeutic agent against neuronal diseases.

Study on an antifouling and blood compatible poly(ethylene–vinyl acetate) material with fluorinated surface structure

Novel poly(ethylene–vinyl acetate) film with fluorinated surface structure was prepared via sequential surface reactions, which are alcoholysis reaction with sodium ethoxide and located fluorination reaction with 2,3,3,3-tetrafluoro-2-[1,1,2,3,3,3-hexafluoro-2-(heptafluoropropoxy)propoxy] propionyl fluoride, respectively. The obtained novel film possesses ordered perfluoroalkyl ether surface layer proved by detailed ATR-FTIR, XPS, and contact angle measurement, which substantiates the success of this new route to get better-tailored surface meeting the biological needs. Hemocompatibility of the resultant films was evaluated by hemolysis test and platelet adhesion test. The results indicated that the poly(ethylene–vinyl acetate) film surface displayed low hemolytic activity and no platelet adhesion due to its extremely low surface tension, which results from the special micro-electric field of perfluoroalkyl ether layer. The yielded transparent film with good properties exhibits a promising application prospect in biology and medical science in view of its flexible substrate and unique biocompatible surface.

TEMPO-Mediated Oxidation of Primary Alcohols to Carboxylic Acids by Exploitation of Ethers in an Aqueous–Organic Biphase System

Abstract Expeditious and benign methods for primary alcohol–carboxylic acid conversions with TEMPO were developed in a biphasic system composed of a slightly miscible ether (THP) and aqueous layer. Easily available co-oxidants such as Py·HBr3, Bu4NBr3, and electrooxidation were successfully applied to generate N-oxoammonium species as a recyclable catalyst.

Glutamate가 유도하는 세포독성으로부터 신경세포를 보호하는 상백피 추출물의 효과

본 연구에서는 glutamate로 유도된 세포독성으로부터 신경세포를 보호하는 상백피(Morus alba) 추출물의 활성을 확인하기 위하여 N18-RE-105 세포주를 이용하여 MTT reduction assay, LDH release assay 및 광학 현미경을 이용하여 형태학적인 변화를 관찰하였다. 그 결과, 상백피 methanol 추출물에서 농도 의존적으로 신경세포 보호효과가 나타났으며, 50 본 연구에서는 glutamate 로 유도된 세포독성으로부터 신경세포를 보호하는 상백피 (Morus alba) 추출물의 활성을 확인하기 위하여 NI8-RE-I05 세포주를 이용하여 MTT reduction assay, LDH release assay 및 광학 현 미 경 을 이 용하여 형태학적인 변화를 관찰하였다. 그 결과y 상백피 methanol 추출물에서 농도 의존적으로 신경세포 보호효과가 나타났으며, 50 <TEX>${\mu}g$</TEX>/ml 농도에서는 80% 이상의 세포생존율을 확인할수 있었다. 이 결과는 N18-RE-105 세포주의 LDH release assay와 형태학적 변화에서도 일치하는 결과를 확인하였다. 가장 높은 활성을 보인 상백피 methanol 추출물을 hexane, diethyl ether, ethyl acetate, water 층으로 분획하여 각 각 1, 5, 10 <TEX>${\mu}g$</TEX>/ml 농도로 처리 시 hexane 층에서 48.0%, 65.6%, 71.5%로 가장 높은 신경세포 보호효과를 확인할 수 있었다. 따라서 상백피 추출물은 glutamate 에 의한 세포독성으로부터 신경세포 손상을 억제하며 신경세포를 보호하는 효과가 있다는 것을 알 수 있었다. This study evaluated the neuroprotective effect of extracts from the root bark of Morus alba (MA) against glutamate-induced cytotoxicity in neuronal cells. Glutamate-induced cytotoxicity was shown by MTT reduction assay. The neuroprotective effects of methanol, ethanol, and acetone extracts from MA against glutamate-induced cytotoxicity were measured. Among the three extracts, the methanolic extracts showed the highest protective effect, as determined by the results of an morphological assay, a lactate dehydrogenase release assay. Furthermore, the methanol extracts were fractionated sequentially with hexane, diethyl ether, ethyl acetate, and water layer according to degree of polarity. The hexane fractions exhibited a neuroprotective effect against glutamate-stressed N18-RE-105 cells. Therefore, these results suggest that extracts of MA could be a new potential candidate as a protective substance against glutamate-induced cytotoxicity.