Repeatability and pattern recognition of bacterial fatty acid profiles generated by direct mass spectrometric analysis of in situ thermal hydrolysis/methylation of whole cells

Direct CI mass spectrometry profiling of fatty acid methyl esters (FAMEs) from in situ thermal hydrolysis/methylation (THM) of whole bacterial cells with tetramethylammonium hydroxide (TMAH) has been demonstrated as a potential method for real time and fieldable detection/identification of microorganisms. Bacillus anthracis (Ames), Yersinia pestis (Nair. Kenya), Vibrio cholerae (E1 Tor), Brucella melitensis (Abortus wild) and Francisella tularensis (LVS vaccine) were profiled by this method during a 10-month period. Repeatability of the in situ FAME data was calculated using one-way analysis of variance (ANOVA) and a t-test. Artificial neural network (ANN) and multivariate statistics of the FAME profiles were also compared for bacterial identification/classification. Equivalent results were obtained with a multivariate rule building expert system (MuRES) and the ANN. However, the ANN analysis required much less computer time and was deemed the best choice for this application. In situ THM FAME profiles of the bacterial samples provided comparable results with those obtained from the Microbial Identification System (MIDI) (Newark, DE) wet chemistry-gas chromatographic based system.     

HPLC determination of ferulic acid in rat plasma after oral administration of Rhizoma Chuanxiong and its compound preparation

An HPLC method is described for determination of ferulic acid in rat plasma. The concentration of ferulic acid in rat plasma was determined after deproteinization with acetonitrile using sulfamethoxazole as internal standard. Chromatographic separations were performed on a C(18) stationary phase with a mobile phase composed of acetonitrile-water (16:84, v/v) with 1% glacial acetic acid. The UV detection wavelength was set at 320 nm. The method was successfully applied to the determination of pharmacokinetic parameters in rat plasma after oral administration of Rhizoma Chuanxiong and and its compound preparation Suanzaoren decoctions. The calibration curve was linear over the range 0.0510-4.08 micro g/mL in rat plasma. Within-day and between-day precisions were less than 4.5% RSD. Mean recovery was determined as 96.9%. The limit of quantitation was 0.0510 micro g/mL. The pharmacokinetic parameters of the two preparations were different significantly (p < 0.05), which may attribute to the effects of other ingredients present in Suanzaoren decoction.     

Fatty Acid Composition of Pistachio Nuts in Turkey

In this study oil yields and fatty acid compositions in the kernels of two varieties (Uzun and Siirt) of pistachio grown in different region of Turkey were investigated. Kernel oils were obtained by Soxhlet extraction using petroleum ether. The yields were found to be 57.1-58.9% and 56.1-62.6 respectively for the Uzun and Siirt varieties, on a moisture-free basis. Fatty acid composition of oils were analysed by GC/MS in the methyl ester form. Fourteen fatty acid components representing about 99% of the total oils were characterised. Oleic acid (55.4-62.6% and 60.7-65.5%, respectively) was the main fatty acid component in both varieties. Pentadecanoic acid, (Z)-7-hexadecenoic acid, margaric acid, Z-7-octadecenoic acid, arachidic acid, 11-eicosenoic acid, and behenic acid were detected in both varieties for the first time.     

Effect of External Acidity of Mordenite-Supported Catalysts on the 2,2-Dimethylbutane Content in Hydroisomerization Products of n-Hexane

We have used potentiometric titration with tetrabutylammonium hydroxide to determine the acid center content on the outer surface of dealuminated natural and synthetic mordenites. We have established a symbatic relationship between the 2,2-dimethylbutane content in the hydroisomerization products of n-hexane on dealuminated palladium-containing mordenites and the number of their external acid centers. We have studied the possibility of partial deactivation of such centers during ion-exchange deposition of palladium on the catalysts, using a tetraammine palladium solution.     

Some Conversions of Thiazoline Carboxylic Acid Esters

We have carried out solvolysis of the previously described ethyl esters of 3-methyl(aryl)-4-methyl-2-thioxothiazoline-5-carboxylic acids, leading to the corresponding acids without breaking down the heterocycle. We synthesized a series of novel esters from the latter by treatment with dimethyl sulfate or reactive halides. Of these, only in the case of the ethyl ester of 3,4-dimethyl-2-thioxothiazoline-5-carboxylic acid did we obtain the hydrazinolysis product (the hydrazide), from which we synthesized novel hydrazones by treatment with aldehydes and ketones.     

Synthesis and characterization of novel functional poly(vinyl alcohol-co-styrene sulfonic acid) copolymers

This paper first time reports the preparation of random anionic copolymers from vinyl acetate (VAc) bearing electro-donating substituent and sodium 4-vinylbenzenesulfonate (SSA) having electro-withdrawing substituent. Copolymers (PVA-co-SSA) of different composition have been successfully prepared by a simple free radical solution polymerization technique. Resulting final copolymer contained neutral hydrophilic as well as ionizable ion exchange sites. Evaluation of spectral data obtained from Fourier transform Infrared spectroscopy, Raman spectroscopy, and ¹H Nuclear magnetic resonance helped in identifying and confirming the chemical structure of copolymers. Characterization of copolymers by gel permeation chromatography revealed high molecular weight with moderate polydispersity index. Analysis of thermal stability and glass transition temperature of copolymers by thermogravimetric analysis and differential scanning calorimetry were found in between corresponding homopolymers. Physicochemical properties of PVA-co-SSA can be beneficial for prospective advanced application in the niche area of smart membrane technology for energy and environment.     

Properties of ethylene propylene diene rubber/white and black filler composites cured by gamma radiation in presence of sorbic acid

The effect of incorporating sorbic acid (SA), an echo-friendly curing agent, and silica or carbon black (CB) filler, as well as gamma irradiation on the physico-chemical, mechanical and thermal properties of ethylene propylene diene monomer rubber (EPDM) was investigated. The results indicated that the developed composites revealed improvement in the studied parameters over the untreated samples. Filler incorporation into rubber matrix has been proven a key factor in enhancing the swelling resistance, tensile strength and thermal properties of the fabricated composites. The improvement in tensile strength and modulus was attributed to better interfacial bonding via SA. Alternatively, a comparison was established between the performance of the white and black fillers. The utmost mechanical performance was reported for the incorporated ratios 10 phr SA and 40 phr white filler into a 50 kGy irradiated composite. Meanwhile, the incorporation of CB yielded better thermally stable composites than those filled with silica at similar conditions.     

Two new triterpenoids from Gardenia jasminoides fruits

A new cycloartane triterpenoid, named gardenolic acid C (1), a new ursane triterpenoid, named 3β,16β,21β,23,24-pentahydroxy urs-12,18,20-trien-28-oic acid γ-lactone (2), together with three know triterpenoids, gardenolic acid A (3), gardenolic acid B (4), and 3α,16β,23,24-tetrahydroxy-28-nor-ursane-12,17,19,21-tetraen (5) were isolated from the fruits of Gardenia jasminoides Ellis. The structures of these compounds were elucidated by analyses of spectroscopic data. All isolates were evaluated for their neuroprotective effects in vitro.

     

Substituent effects on the Lewis acidity of 4,6-di-tert-butylchatechol boronate esters

In studying the factors which contribute to the Lewis acidity of organoboron compounds we investigated approaches to the design of robust, novel Lewis acids purposed for metal-free catalysis. Based on a sterically encumbered catechol motif, a series of boronate esters are shown to demonstrate modest Lewis acidities for the conventional Gutmann-Beckett test as an inquisitive investigation.     

Formal [4+2] cycloaddition of 3-phenylcyclobutanones with nitriles

Various 3-phenylcyclobutanones reacted with aliphatic and aromatic nitriles in the presence of Me₃SiOTf to afford dihydropyridones by formal [4+2] cycloaddition.