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You-Sin Jian,1 Ching-Wen Chen,1 Chih-An Lin,2 Hsiu-Ping Yu,1 Hua-Yang Lin,3 Ming-Yuan Liao,1 Shu-Huan Wu,1 Yan-Fu Lin,1 Ping-Shan Lai1,2,4,5 1Department of Chemistry, 2PhD Program in Tissue Engineering and Regenerative Medicine, National Chung Hsing University, Taichung, 3Preclinical Development Research Department, Holy Stone Healthcare Co., Ltd., Taipei, 4Research Center for Sustainable Energy and Nanotechnology, 5Rong Hsing Research Center for Translational Medicine, National Chung Hsing University, Taichung, Taiwan Abstract: Carrier-mediated drug delivery systems are promising therapeutics for targeted delivery and improved efficacy and safety of potent cytotoxic drugs. Nimesulide is a multifactorial cyclooxygenase 2 nonsteroidal anti-inflammatory drug with analgesic, antipyretic and potent anticancer properties; however, the low solubility of nimesulide limits its applications. Drugs conjugated with hyaluronic acid (HA) are innovative carrier-mediated drug delivery systems characterized by CD44-mediated endocytosis of HA and intracellular drug release. In this study, hydrophobic nimesulide was conjugated to HA of two different molecular weights (360 kDa as HA with high molecular weight [HAH] and 43kDa as HA with low molecular weight [HAL]) to improve its tumor-targeting ability and hydrophilicity. Our results showed that hydrogenated nimesulide (N-[4-amino-2-phenoxyphenyl]methanesulfonamide) was successfully conjugated with both HA types by carbodiimide coupling and the degree of substitution of nimesulide was 1%, which was characterized by 1H nuclear magnetic resonance 400 MHz and total correlation spectroscopy. Both Alexa Fluor® 647 labeled HAH and HAL could selectively accumulate in CD44-overexpressing HT-29 colorectal tumor area in vivo, as observed by in vivo imaging system. In the in vitro cytotoxic test, HA–nimesulide conjugate displayed >46% cell killing ability at a nimesulide concentration of 400 µM in HT-29 cells, whereas exiguous cytotoxic effects were observed on HCT-15 cells, indicating that HA–nimesulide causes cell death in CD44-overexpressing HT-29 cells. Regarding in vivo antitumor study, both HAL–nimesulide and HAH–nimesulide caused rapid tumor shrinkage within 3 days and successfully inhibited tumor growth, which reached 82.3% and 76.4% at day 24 through apoptotic mechanism in HT-29 xenografted mice, without noticeable morphologic differences in the liver or kidney, respectively. These results indicated that HA–nimesulide with improved selectivity through HA/CD44 receptor interactions has the potential to enhance the therapeutic efficacy and safety of nimesulide for cancer treatment. Keywords: COX-2 inhibitor, nimesulide, hyaluronic acid, CD44, colorectal cancer

Photodynamic therapy (PDT) is a light-activated photochemical reaction that induces localized tissue damage for the treatments of cancers and other nonmalignant conditions through the generation of reactive oxygen species. In the clinic, patients treated with PDT reveal strong skin photosensitivity and thus should be kept away from direct sunlight. In our previous study, we demonstrated that the skin phototoxicity of meta-tetra(hydroxyphenyl)chlorin (m-THPC), a photosensitizer used in the clinic, can be significantly reduced after micellar encapsulation. In this present work, m-THPC was loaded into artificial oil bodies (AOBs) to improve its biocompatibility with self-aggregation. Our results show that the m-THPC-loaded oil bodies with particle size around 100 nm significantly enhanced the nuclear localization of m-THPC, whereas m-THPC-loaded Pluronic® F68 micelles were only observed in the cytosol. In addition, m-THPC-loaded oil bodies had better PDT efficacy than those m-THPC-loaded polymeric mi...

Moringa oleifera Lam. (Moringaceae), commonly known as the drumstick tree or the horseradish tree, is a shrub and small deciduous tree of 2.5 to 10 m height [1]. The leaves of the titled plant, as well as the flowers, roots, gums, fruits, and seeds, are extensively used for treating cardiovascular disease [2], liver disease [3], cancer [4], and hematologic, hepatic, and renal disease [5]. Compared to extensive medicinal studies, the limited phytochemical investigations report mainly the identification of glycosides and alkaloids such as 4-( -L-rhamnosyloxybenzylglucosinolate), niazimicin, niazirin, and moringine [6–9]. Breast cancer is a disease of humans and other mammals; while the overwhelming majority of cases in humans involve women, men can also develop breast cancer [10, 11]. MCF-7 and two other tumor cell lines account for more than two-thirds of all human breast cancer reported cases. Clinically, the number of doxorubicin-resistant MCF-7 adenocarcinoma (MCF-7/ADR) cases has grown, making traditional chemotherapy fail. In the preliminary trials performed by our group, the low-polarity fraction of the methanol extracts of the root barks of M. oleifera at 50 g/mL concentration displayed significant cytotoxicity against MCF-7/ADR tumor cell lines with an inhibition percentage of 56%. Therefore, in our continuing program aimed at the discovery of new anti-tumor drugs, M. oleifera was selected as the target, and in present study we wish to report the structural elucidation of compounds 1 and 2 and the cytotoxicity of some of these isolates towards the MCF-7/ADR adenocarcinoma cell lines. Air-dried and powdered root barks of M. oleifera were extracted with MeOH under reflux. The methanol extracts were purified using a combination of conventional chromatographic techniques. N-benzylcarbamic acid (1) and 4-( -L-rhamnopyranosyloxy)benzaldehyde (2), along with 25 known compounds, were identified, and comprehensive studies of their spectral and physical data were made. Compound 1 was isolated as a white powder with mp 244–245 C, and the HR-MS analytical data of 1 displayed a pseudomolecular ion peak at m/z 152.0736 corresponding to the molecular formula of C8H9NO2. The UV absorption maxima at 267 and 211 nm were characteristic of the existence of a benzenoid moiety [12]. The IR absorption bands at 3322 and 1621 cm–1 suggested the presence of hydroxyl and amide carbonyl groups, respectively. In the 1H NMR spectrum, a set of mutually coupled aromatic proton signals at 7.25–7.32 (5H, m) and a doublet signal at 4.36 (2H, J = 5.7 Hz, H-1 ) indicated the partial structure of the benzyl moiety. In addition, in the 13C NMR spectrum, the carbon signal at 158.0 (C-3 ) was characteristic of a carbamic acid group in compound 1, and another set of aromatic carbon signals at 139.0 (C-1), 128.7 (C-3, 5), and 127.4 (C-2, 6), 127.4 (C-4) confirmed the presence of a mono-substituted benzene basic structure. Thus, the chemical structure of 1 was established as N-benzylcarbamic acid. Although this compound had already been reported in the previous synthesis work [13], this is the first report from a natural source.

In this study, we developed curcumin-encapsulated hyaluronic acid–polylactide nanoparticles (CEHPNPs) to be used for liver fibrosis amelioration. CD44, the hyaluronic acid (HA) receptor, is upregulated on the surface of cancer cells and on activated hepatic stellate cells (aHSCs) rather than normal cells. CEHPNPs could bind to CD44 and be internalized effectively through endocytosis to release curcumin, a poor water-soluble liver protective agent. Thus, CEHPNPs were potentially not only improving drug efficiency, but also targeting aHSCs. HA and polylactide (PLA) were crosslinked by adipic acid dihydrazide (ADH). The synthesis of HA–PLA was monitored by Fourier-transform infrared (FTIR) and Nuclear Magnetic Resonance (NMR). The average particle size was approximately 60–70 nm as determined by dynamic light scattering (DLS) and scanning electron microscope (SEM). Zeta potential was around −30 mV, which suggested a good stability of the particles. This drug delivery system induced significant aHSC cell death without affecting quiescent HSCs, hepatic epithelial, and parenchymal cells. This system reduced drug dosage without sacrificing therapeutic efficacy. The cytotoxicity IC50 (inhibitory concentration at 50%) value of CEHPNPs was approximately 1/30 to that of the free drug treated group in vitro. Additionally, the therapeutic effects of CEHPNPs were as effective as the group treated with the same curcumin dose intensity in vivo. CEHPNPs significantly reduced serum aspartate transaminase/alanine transaminase (ALT/AST) significantly, and attenuated tissue collagen production and cell proliferation as revealed by liver biopsy. Conclusively, the advantages of superior biosafety and satisfactory therapeutic effect mean that CEHPNPs hold great potential for treating hepatic fibrosis.

L-cysteine capped Mn2+-doped ZnS quantum dots are prepared as a fluorescence probe for the detection of heavy metal contaminants, such as As2O42-, Cd2+, CrO42-, Ni2+, Zn2+, Ca2+, Fe2+, Cu2+, Pb2+, Co2+ and Mn2+ ions. The results show L-cysteine capped Mn2+-doped ZnS quantum dots exhibit good sensitivity and selectivity for the detection of copper ions. The relationship between the detection limit, linear range and the concentration of quantum dots are examined. The optimum fluorescence sensor is obtained at the L-cysteine-ZnS QDs concentration of 2 mg/mL and pH 7.0 in phosphate buffer. The limit of detection for this sensor system is 0.2 ppm with the linear range between 0.5 and 20 ppm. The effect of foreign ions from Mn2+, Fe2+, Co2+ and Ni2+ for the detection of Cu2+ solution is also evaluated. The results show there is no significant difference on the measurement of quenching effect.

Crude extracts of Sedum formosanum N.E.Br. obtained from n-butanol partition (BP) and isopropanol salting-out pretreatment (ISP) were analyzed using antioxidation assays. The results indicated that the extract from ISP contained more potent antioxidants and thus exhibited more antioxidant activity in all the assays. The superoxide radical-scavenging activity and inhibition of nitric oxide radicals achieved after ISP were 3.65 and 2.18 times higher than those achieved through BP, respectively. Eight bioactive natural products were isolated and identified according to an analysis of antioxidation activity in different fractions of the ISP crude extract, namely three cyanophoric glycosides 1–3, three flavonoids 4–6 and two phenolic compounds (7 and a new compound 8). Among them, compounds 5 and 6 exhibit the highest antioxidation capability, and the ISP is suitable for obtaining compounds 5 and 6 using HPLC chromatograms. Therefore, ISP is an excellent extraction technology that can be used to extract antioxidant compounds in the nutraceutical and pharmaceutical industries.

BACKGROUND: 2-Phenylethyl acetate (2-PEAc) is a highly valued natural volatile ester with a rose-like odour that is widely used to add scent or flavour to cosmetics, soaps, foods and drinks. In this study, 2-PEAc was synthesised enzymatically by transesterification of vinyl acetate with 2-phenethyl alcohol catalysed by immobilised lipase (Novozym® 435) from Candida antarctic RESULTS: Response surface methodology and a three-level/three-factor Box–Behnken design were used to evaluate the effects of time, temperature and enzyme amount on the molar conversion % of 2-PEAc. The results showed that temperature was the most important variable. Based on the ridge max analysis results, optimum enzymatic synthesis conditions were predicted as a reaction time of 79 min, a temperature of 57.8 °C and an enzyme amount of 122.5 mg. The predicted and experimental yields were 86.4 and 85.4% respectively. CONCLUSION: Three immobilised lipases were screened and 15 reaction conditions were tested in order to find the combination for maximum yield. The optimisation of 2-PEAc synthesis catalysed by Novozym® 435 was successfully developed. The kinetic study of this transesterification reaction showed that it followed an ordered ping-pong bi-bi mechanism without any inhibition by reactants. Copyright © 2012 Society of Chemical Industry

Five different morphologies selectively synthesized through a microwave hydrothermal route in order to determine the dependence of degradation efficiency on TiO2 morphologies. These five morphologies include nanosphere, nanotube, hollow sphere, nanorod and granule-like particle. Scanning electron microscopy, X-ray diffraction and Brunauer-Emment-Teller methods were used to characterize the morphologies, crystalline structures, and specific surface area of these nanostructured TiO2. Oxidants were used as sacrificial electron acceptor to accelerate the degradation. The degradation mechanism of oxalic acid on the surface of TiO2 influenced by oxidants was discussed.

Recently, superparamagnetic chemically disordered face-centered cubic (fcc) FePt nanoparticles have been demonstrated as superior negative contrast agents for magnetic resonance imaging (MRI). However, their low intracellular labeling efficiency has limited the potential usage and the nanotoxicity of the particles requires attention. We have developed fluorescein isothiocyanate-incorporated silica-coated FePt (FePt@SiO2-FITC) nanoparticles that exhibited not only a significantT1andT2MR contrast abilities but also a fluorescent property without significant cytotoxicities. These results suggest that silica-coated superparamagnetic FePt nanoparticles are potential nanodevices for the combination of fluorescence and MRI contrast used for cancer diagnosis.

Matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOFMS) is a rapid and sensitive tool for characterizing a wide variety of biomolecules. However, invisible "sweet spots" that form during heterogeneous cocrystallization minimize the analytical throughput and affect the reproducibility of MALDI analysis. In this study, visible "sweet spots" were generated on a metallic sample plate by quantum dots (QDs)-assisted MALDI analysis. To the best of our knowledge, this is the first report to demonstrate that "sweet spots" can be observed directly without using a microscope. The proper proportion of matrix to QDs that results in optimal crystallization was also examined. The signals of standard peptides and phosphopeptides obtained by QD-assisted MALDI analysis were 5- and 3-fold higher, respectively, than those obtained by conventional MALDI analysis. For peptide mixtures, the QD-assisted MALDI analysis not only resulted in more intense peptide signals but also resulted in a greater number of peaks, thereby allowing for better detection of individual peptides in peptide mixtures. Moreover, we demonstrated that application of QDs to a radiate microstructure chip followed by MALDI analysis enhanced the detection of peptide signals. Overall, we show that this method is a simple, sensitive, and high-throughput technique for peptide detection.

A folic acid-anchored, poly(ethylene glycol)-linked (PEGgylated) phospholipid and an immunoaffinity chromatographic column were prepared and employed to develop a liposomal immunodiagnostic assay for the direct determination of folic acid (FA) in this study. Distearoylphosphatidylethanolamine-poly(ethylene glycol)2000-folic acid (DSPE-PEG2000-FA) was synthesized through carbodiimide-mediated coupling of FA and DSPE-PEG2000-amine and characterized using thin layer chromatography, 1H nuclear magnetic resonance spectroscopy, and electrospray ionization-mass spectrometry. Liposomal biolabels were constructed using the synthesized DSPE-PEG2000-FA in conjunction with other phospholipids. A stationary phase having affinity for FA was prepared by covalently linking purified anti-FA monoclonal antibodies onto N-hydroxysuccinimide-activated Sepharose beads, which were subsequently packed into a 1.9 cm diameter polypropylene column. The calibration curve for FA had a linear range from 10(-8) to 10(-4) M. The limit of detection was 6.8 ng (equivalent to 500 microL of 3.1 x 10(-8) M FA). The elution buffer (35% methanol in Tris buffered saline containing 0.1% Tween 20) also served as the regeneration buffer, which allowed the same column to be used for up to 50 times without any observable loss of reactivity. The immunoaffinity chromatographic column was reusable and capable of concentrating analytes from sample solution; in conjunction with folic acid-sensitized liposomal biolabels, however, they hold great potential as sensitive immunoaffinity assays for the determination for FA. To confirm the feasibility of using this system in the analysis of real samples, the folic acid contents of three over-the-counter vitamin supplements were tested. The recoveries of folic acid of 90-112% for these three samples were obtained, suggesting contents that were consistent with the information obtained from their nutritional facts panels.

Four metal benzylalkoxides, [L(2)M(2)(mu-OBn)(2)] (M = Mg or Zn), based on NNO-tridentate ketiminate ligands are synthesized and characterized. X-ray crystal structural studies of [(L(1))(2)Mg(2)(mu-OBn)(2)] (1a) and [(L(1))(2)Zn(2)(mu-OBn)(2)] (1b) (L(1)-H = (Z)-4-((2-(dimethylamino)ethylamino)(phenyl)methylene)-3-methyl-1-phenyl-pyrazol-5-one) reveal that both complexes 1a and 1b are dinuclear species whereas the geometry around the metal center is penta-coordinated bridging through the benzylalkoxy oxygen atoms in the solid structure. The activities and stereoselectivities of these four complexes toward the ring-opening polymerization Of L-lactide and rac-lactide are investigated. Polymerization Of L-lactide initiated by these four metal benzyloxides proceeds rapidly with good molecular weight control and yields polymer with a very narrow molecular weight distribution. The kinetic studies for the polymerization of L-lactide with compound 1a show first order in both compound 1a and lactide concentrations with the polymerization rate constant, k, of 6.94 M/min. Besides, experimental results demonstrate that among these metal benzylalkoxides, complex 1a exhibits the highest stereoselectivity with a Pr up to 87% and complex 1b possesses the highest activity indicating that the terminal group of NNO-tridentate ketimine ligands exerts a significant influence on both the reactivity and stereoselectivity of these complexes. (C) 2009 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 47: 2318-2329, 2009

Single transition operators are adapted to simplify the density matrix theory for the spin dynamics calculation of quadrupole nuclei with more than one spin transition in zero field. We employ the formalism on the spin I=5/2 system with axial symmetry to obtain the responses of multiple pulses for nuclear quadrupole resonance regardless the spin relaxation. The theoretical calculation for pulse response is illustrated from one-pulse to multipulse and one-dimension to multidimension explicitly. Subsequently sensitivity-enhanced nuclear quadrupole correlation spectroscopy (SENQCOSY) is proposed and demonstrated. Experimental results are compared with conventional nuclear quadrupole correlation spectroscopy (NQCOSY) for 121Sb (I=5/2) in SbCl3 system. The maximum sensitivity is enhanced by a factor of 2.66, which are in good agreement with theoretical prediction.

Luobuma (Apocynum venetum L. (AVL)) is a popular beverage in Asia and has been reportedly to be associated with the bioactivities such as cardiotonic, diuretic, antioxidative, and antihypertensive. However, its biofunction as chemoprevention activity is seldom addressed. Herein, we aimed to characterize the anti-androgen-insensitive-prostate-cancer (anti-AIPC) bioactive compounds of Luobuma, and to investigate the associated molecular mechanisms. Activity-guided-fractionation (antioxidative activity and cell survivability) of Luobuma ethanolic extracts was performed to isolate and characterize the major bioactive compounds using Ultra Performance Liquid Chromatography (UPLC), Liquid Chromatography-Mass Spectrometry (LC-MS), and Nuclear Magnetic Resonance (NMR). Plant sterols (lupeol, stigamasterol and β-sitosterol) and polyphenolics (isorhamnetin, kaempferol, and quercetin) were identified. Lupeol, a triterpene found in the fraction (F8) eluted by 10% ethyl acetate/90% hexane and accounted for 19.3% (w/w) of F8, inhibited the proliferation of PC3 cells. Both lupeol and F8 induced G2/M arrest, inhibition of β-catenin signaling, regulation of apoptotic signal molecules (cytochrome c, Bcl-2, P53, and caspase 3 and 8), and suppression DNA repair enzyme expression (Uracil-DNA glycosylase (UNG)). To our knowledge, our study is the first report that lupeol inhibited the expression of UNG to elicit the cytotoxicity against androgen-insensitive-prostate-cancer cells. Collectively, Luobuma, which contains several antitumor bioactive compounds, holds the potential to be a dietary chemopreventive agent for prostate cancer.

The aim of this study was to identify and quantify the bioactive constituents in the methanol extracts of Coptis Rhizome prepared by ultrafining technology. The indicator compound was identified by spectroscopic method and its purity was determined by HPLC. Moreover, the crude extracts and indicator compound were examined for their ability to inhibit the growth ofRhizoctonia solaniKühn AG-4 on potato dextrose agar plates. The indicator compound is a potential candidate as a new plant derived pesticide to controlRhizoctoniadamping-off in vegetable seedlings. In addition, the extracts of Coptis Rhizome prepared by ultrafining technology displayed higher contents of indicator compound; they not only improve their bioactivity but also reduce the amount of the pharmaceuticals required and, thereby, decrease the environmental degradation associated with the harvesting of the raw products.

Crystalline LiMn2O4 materials were synthesized through a low temperature reflux (LTR) process. The LTR material exhibits an essential electrochemical behavior to present only one transition during the charge/discharge process and gives promises for the future application. The X-ray data hardly distinguishes either conventional high temperature (HT) or LTR material since both materials possess similar molecular structure. However, solid-state NMR results suggest substantial difference for their electronic structure. The 7Li-NMR of HT material exhibits the isotropic peak at 529 ppm and spreads for 160 kHz wide indicating the interaction between the lithium nucleus and the conducting electrons around the nucleus. The LTR material presents the main isotropic peak at 217 ppm but spreads for almost 400 kHz wide asymmetrically implying the existence of multiple electronic environments.

A variety of two dimensional two-and three-dimensional NQR experiments are reviewed, showing their application to the determination of field gradients for important sites in peptides and proteins, for assigning connected transitions of nuclei with spin ≥ 5/2, and for determining hexadecapolar coupling constants. The quadrupole coupling tensor for 63Cu in the active site of a protein, bovine erythrocyte (Cu, Zn) superoxide dismutase, has been measured and is compared with the results of ab initio calculations.

Three methods for two-dimensional correlation nuclear magnetic resonance spectroscopy at zero field are discussed. All three involve coherence transfer via longitudinal polarization, double quantum coherence, or both in parallel. The double quantum pulse sequences exploit the spinor property of spin states. These sequences have been applied to connected Δm=1 transitions, as well as for the indirect detection of forbidden or nearly forbidden Δm>1 transitions.

A low-temperature electrochemical synthesis of water-stabilized KxCoO2·yH2O crystal has been demonstrated. Temperature variable X-ray diffractions display a sandwiched structure with mobile water molecules. The crystal has hexagonal characteristic with four adjustable phases K0.35CoO2·0.40H2O, K0.35CoO2·0.34H2O, K0.22CoO2·0.21H2O, and anhydrous K0.15CoO2. Lattice water removal in a step-by-step process with the reduction of interlayer spacing in a single crystal can be achieved. Strong anisotropic conducting at low temperature and weak interlayer coupling in the ab plane have been demonstrated.

Noise excitation has been applied to the problem of a spin-3/2 quadrupolar nuclear spins in zero magnetic field. We demonstrate that high-sensitivity spectra can be observed with very weak rf pulses and that the growth in signal intensities follows a universal curve which is simply related to the applied pulse angle, the spacing between those pulses, and the T1 of the nuclear spin system. These signal intensites are closely related to those observed in NMR experiments exploiting similar excitation sequences. Such sequences have numerous practical advantages and in particular may be applied to large volume samples, or to nuclear spins which interact only weakly with magnetic fields, without sacrifice in either spectral bandwidth or signal intensity.

In this communication, we present experiments in low-temperature NMR on two samples. Performance on broadlinespectra and at very low temperatures was demonstrated by observing the 19 F signals in sodium trifluoroacetate.

Two dimensional nuclear quadrupole correlation spectroscopy has been used to measure simultaneously the two nuclear spin transition frequencies for the iodine resonance of cadmium iodide at zero magnetic field. Because of the layer structure and resultant polymorphism in this substance, conventional zero‐field NMR spectra are inhomogeneously broadened by several hundred kHz. However, the 2D spectra obtained by our method are subject only to homogeneous linewidth, which for this compound is of the order of 5 kHz. This greatly increased precision allows more accurate evaluation of the nuclear hexadecapole coupling in cadmium iodide; which we measure as 0.216±0.514 kHz (i.e., indistinguishable from zero). This gives a maximum value of the nuclear hexadecapole moment several times lower than that recently reported for the same nucleus in potassium iodide.

2-Phenylethyl acetate (2-PEAc) is a highly valued natural volatile ester with a rose-like odour that is widely used to add scent or flavour to cosmetics, soaps, foods and drinks. In this study, 2-PEAc was synthesised enzymatically by transesterification of vinyl acetate with 2-phenethyl alcohol catalysed by immobilised lipase (Novozym(®) 435) from Candida antarcticResponse surface methodology and a three-level/three-factor Box-Behnken design were used to evaluate the effects of time, temperature and enzyme amount on the molar conversion % of 2-PEAc. The results showed that temperature was the most important variable. Based on the ridge max analysis results, optimum enzymatic synthesis conditions were predicted as a reaction time of 79 min, a temperature of 57.8 °C and an enzyme amount of 122.5 mg. The predicted and experimental yields were 86.4 and 85.4% respectively.Three immobilised lipases were screened and 15 reaction conditions were tested in order to find the combination for maximum yield. The optimisation of 2-PEAc synthesis catalysed by Novozym(®) 435 was successfully developed. The kinetic study of this transesterification reaction showed that it followed an ordered ping-pong bi-bi mechanism without any inhibition by reactants.

Sesame (Sesamum indicum L.) seed has been recognized as a nutritional protein source owing to its richness in methionine. Storage proteins have been implicated in allergenic responses to sesame consumption. Two abundant storage proteins, 11S globulin and 2S albumin, constitute 60-70 and 15-25% of total sesame proteins, respectively. Two gene families separately encoding four 11S globulin and three 2S albumin isoforms were identified in a database search of 3328 expresssed sequence tag (EST) sequences from maturing sesame seeds. Full-length cDNA sequences derived from these two gene families were completed by PCR using a maturing sesame cDNA library as the template. The amino acid compositions of these deduced storage proteins revealed that the richness in methionine is attributed mainly to two 2S albumin isoforms and partly to one 11S globulin isoform. The presence of four 11S globulin and three 2S albumin isoforms resolved in SDS-PAGE was confirmed by MALDI-MS analyses. The abundance of these isoforms was in accord with the occurrence frequency of their EST sequences in the database. A comprehensive understanding of these storage proteins at the molecular level may also facilitate the identification of allergens in crude sesame products that have caused severe allergic reactions increasingly reported in the past decade.

The reaction of NaCo(CO) 4 with trans -1-bromppenta-2,4-diene in tetrahydrofuran at −78°C affords ( syn -η 3 -2,4-pentadienyl)Co(CO) 3 ( 1 ) in moderate yield. Addition of triphenylphosphine to 1 in ether at 0°C gives ( syn -η 3 -2,4-pentadienyl)Co(CO) 2 [P(C 6 H 5 ) 3 ] ( 2a ). In solution, 2a equilibrates with its anti isomer ( 2b ) at room temperature. The crystal structure of 2a has been determined by X-ray diffraction analysis. Compound 2a crystallizes in the triclinic space group P 1 with lattice parameters: a 10.326(2), b 10.763(4), c 11.452(2) A, α 105.99(2), β 100.10(1), γ 108.05(2)°; V 1114.98 A 3 , Mol. wt. 539.69, D (calcd.) 1.324 g/cm 3 and Z = 2. The structure was solved and refined to R and R w values of 0.0357 and 0.0408, respectively for 4046 reflections.