Aliphatic Constituents Research Articles

High-Resolution Mass Spectrometry-Based Chemical Fingerprinting of Baijiu, a Traditional Chinese Liquor.

Fourier transform ion cyclotron resonance (FT-ICR) mass spectrometry, coupled with electrospray ionization (ESI) or atmospheric-pressure photoionization (APPI), was employed for chemical fingerprinting of baijiu, a traditional Chinese liquor. Baijiu is the most consumed distilled alcoholic beverage globally, with over 10 billion liters sold annually. It is a white (transparent) spirit that exhibits similarities to dark spirits such as whisky or rum in terms of aroma and mouthfeel. In this study, direct-infusion FT-ICR mass spectrometry was used to analyze 10 commercially available baijiu liquors, enabling the examination of both volatile and nonvolatile constituents without the need for tedious sample extractions or compound derivatizations. The chemical fingerprints obtained by FT-ICR MS revealed substantial compositional diversity among different baijiu liquors, reflecting variations in the raw materials and production methods. The main compounds identified included a variety of acids, esters, aldehydes, lactones, terpenes, and phenolic compounds. The use of ESI and APPI provided complementary compositional information; while ESI demonstrated greater selectivity toward polar, aliphatic sample constituents, APPI also ionized semipolar and nonpolar (aromatic) ones.

Investigation of lignin substructures participating in self-assembly for the synthesis of monodisperse lignin spherical particles

The intricate structure of lignin, characterized by a mix of hydrophilic components and hydrophobic structures from its aliphatic and aromatic constituents, poses challenges in creating monodisperse particles. This is due to the need for precise modulation of self-assembly kinetics. Herein, we explore a correlation between the substructure of lignin and its capacity for self-assembly. We have conducted an in-depth investigation into the interactions between hydrophilic groups, such as phenolic and aromatic-OH, and monolignols with interunit linkages that are involved in the formation of lignin particles (LPs). A high degree of hydrophilicity with a condensed structure is crucial for high supersaturation levels, which in turn determines the growth phase and leads to small LPs. An approach based on tailoring the supersaturation level which is contingent on the structural characteristics of extracted organosolv lignin was used to obtain remarkably uniform LPs with mean diameters of approximately 230 and 480 nm. The results of this study have the potential to serve as a foundation for the preparation of monodisperse LPs derived from various lignin sources as well as for the development of methods to extract lignin containing a specific chemical substructure.

Emergence of hydrocarbon-degrading bacteria in crude oil-contaminated soil in a hyperarid ecosystem: Effect of phosphate addition and augmentation with nitrogen-fixing cyanobacteria on oil bioremediation

Hyperarid hot deserts impose limiting conditions for microbial activity, thus delaying crude oil biodegradation resulting from accidental spills. This study examined the emergence of oil-degrading bacterial species in the soil of a hyperarid area in the southern Negev desert, Israel, which was exposed to a major oil spill. Amplicon sequencing of the 16S rRNA gene showed dominance of the phyla Proteobacteria and Actinobacteria in both contaminated and control soils. Significant differences were seen in the abundance of the phylum Firmicutes. Classes Actinobacteria, Gammaproteobacteria and Bacilli dominated the oil-contaminated soil. Bacterial species capable of degrading aromatic and aliphatic oil constituents were isolated from the contaminated soil. Contaminated soil microcosms were amended separately with nitrogen, phosphorus, or nitrogen-fixing cyanobacteria (NFC) biomass; the highest reduction in total petroleum hydrocarbons was observed in the phosphorus-supplemented soil. The abundance of alkB gene, encoding alkane monooxygenase, increased significantly in the control, NFC and phosphate treatments, but not in the nitrogen treatment. However, nahA abundance (coding for naphthalene dioxygenase) was only considerably increased with the phosphorus amendment. While nitrogen amendment via NFC bioaugmentation is a sustainable and novel biostimulation method, phosphorus amendment significantly accelerates the biodegradation of crude oil under extremely arid conditions.

Alteration of organic macerals by uranium irradiation in lower Paleozoic marine shales

Measuring the degree of organic matter (OM) alteration caused by uranium (U) irradiation is important in the effective evaluation of the hydrocarbon potential and thermal maturity of U-rich source rocks. This study investigates OM alteration in the Baltoscandian U-rich, lower Paleozoic Alum shale obtained from three research wells in the thermally immature parts of eastern Sweden and western Estonia. The results show a marked increase in the proportion of refractory, non-generative organic carbon (NGOC) in the U-rich shale. Fluorescence spectrometry of unicellular alginites and lamalginites show a reduction of up to 95.6% in fluorescence relative intensity (RI) with increase in U content from 29 to 401 ppm. Fluorescence spectra of the liptinites exhibit a marked “red shift” as expressed by increase in red(R)/green(G) quotients. This change in fluorescence properties of the liptinites is associated with up to 77.6% decrease in hydrogen index (HI) and hence loss of hydrocarbon generation potential. Furthermore, organic molecules show significant loss of aromatic moieties as well as aliphatic constituents resulting in a more condensed macromolecular structure. The measured random reflectance of solid bitumen (BRo) appears to be significantly elevated in micro scale proximity to the U-containing minerals. The heterogeneous distribution of U-containing minerals and the contact with solid bitumen attributes to the wider range of BRo values and lead to the overall increase in mean BRo in samples with high U contents. In contrast, Ro values of zooclast macerals (GRo, e.g., graptolite, chitinozoans and vitrinite-like fragments) appear to be less influenced by U irradiation and hence are a more reliable maturity indicator in U- rich lower Paleozoic shales.

Variations in Triterpenoid Deposition in Cuticular Waxes during Development and Maturation of Selected Fruits of Rosaceae Family.

The process of fruit ripening involves many chemical changes occurring not only in the mesocarp but also in the epicarp, including changes in the triterpenoid content of fruit cuticular waxes that can modify the susceptibility to pathogens and mechanical properties of the fruit surface. The aim of the study was the determination of the ripening-related changes in the triterpenoid content of fruit cuticular waxes of three plant species from the Rosaceae family, including rugosa rose (Rosa rugosa), black chokeberry (Aronia melanocarpa var. “Galicjanka”) and apple (Malus domestica var. “Antonovka”). The triterpenoid and steroid content in chloroform-soluble cuticular waxes was determined by a GC-MS/FID method at four different phenological stages. The profile of identified compounds was rather similar in selected fruit samples with triterpenoids with ursane-, oleanane- and lupane-type carbon skeletons, prevalence of ursolic acid and the composition of steroids. Increasing accumulation of triterpenoids and steroids, as well as the progressive enrichment of the composition of these compounds in cuticular wax during fruit development, was observed. The changes in triterpenoid content resulted from modifications of metabolic pathways, particularly hydroxylation and esterification, that can alter interactions with complementary functional groups of aliphatic constituents and lead to important changes in fruit surface quality.

Sustainable plant polyesters as substrates for optical gas sensors.

The fast and non-invasive detection of odors and volatile organic compounds (VOCs) by gas sensors and electronic noses is a growing field of interest, mostly due to a large scope of potential applications. Additional drivers for the expansion of the field include the development of alternative and sustainable sensing materials. The discovery that isolated cross-linked polymeric structures of suberin spontaneously self-assemble as a film inspired us to develop new sensing composite materials consisting of suberin and a liquid crystal (LC). Due to their stimuli-responsive and optically active nature, liquid crystals are interesting probes in gas sensing. Herein, we report the isolation and the chemical characterization of two suberin types (from cork and from potato peels) resorting to analyses of gas chromatography–mass spectrometry (GC-MS), solution nuclear magnetic resonance (NMR), and X-ray photoelectron spectroscopy (XPS). The collected data highlighted their compositional and structural differences. Cork suberin showed a higher proportion of longer aliphatic constituents and is more esterified than potato suberin. Accordingly, when casted it formed films with larger surface irregularities and a higher C/O ratio. When either type of suberin was combined with the liquid crystal 5CB, the ensuing hybrid materials showed distinctive morphological and sensing properties towards a set of 12 VOCs (comprising heptane, hexane, chloroform, toluene, dichlormethane, diethylether, ethyl acetate, acetonitrile, acetone, ethanol, methanol, and acetic acid). The optical responses generated by the materials are reversible and reproducible, showing stability for 3 weeks. The individual VOC-sensing responses of the two hybrid materials are discussed taking as basis the chemistry of each suberin type. A support vector machines (SVM) algorithm based on the features of the optical responses was implemented to assess the VOC identification ability of the materials, revealing that the two distinct suberin-based sensors complement each other, since they selectively identify distinct VOCs or VOC groups. It is expected that such new environmentally-friendly gas sensing materials derived from natural diversity can be combined in arrays to enlarge selectivity and sensing capacity.

Phytochemical, HPLC and FTIR Analysis of Methanolic Extract from Gracilaria dura (C Agardh) J Agardh.

Marine algae are known to contain a wide variety of bioactive compounds. They are also rich in novel biomolecules and can be explored for the development of drugs to combat lifestyle diseases like cancer, diabetes etc. Red algae are known for their nutraceutical and functional importance. But there are a lot of limitations regarding their availability and in estimating which algal fractions are biologically active. Similarly, the mode of digestion of such compounds in human body is not yet properly traced. In this juncture, the present study was aimed to evaluate the phytochemical screening of the methanolic extract of the red alga, Gracilaria dura. Methanolic extract of G. dura showed the presence of reducing sugar, flavonoids, glycosides, tannins and terpenoids. Further, the HPLC analysis was attempted to fractionate the polyphenolics. Various phenolic acids such as of gallic acid, vanillic acid, sinapic acid, p-coumaric acid, hydroxybenzoic, phloroglucinol, catechol and cinnamic acid were identified. Subsequently, the methanolic solvent extract of G. dura was subjected to fourier transform infrared spectroscopy for the analysis of the functional groups. The results based on the spectral data of FTIR revealed the presence of aliphatic constituents containing alkanes, ketones, alkyl halides, hydroxyl groups etc. Thus, the observed finding envisages that methanolic extract of G. dura contained potential bioactive compounds which can be used for analysing the various biological activities.
 Keywords: Gracilaria dura, Phytochemical, Methanolic extract, HPLC, FTIR

How do ions contribute to brine-hydrophobic hydrocarbon Interfaces? An in silico study

HypothesisThe saltwater-oil interface is of broad implication in geochemistry and petroleum disciplines. To date, the main focus has been on the surface contribution of polar, heavy compounds of crude oil, widely neglecting the role of non-polar hydrocarbons. However, non-polar compounds are expected to contribute to characteristics of oil-brine interfaces. MethodologyUtilizing molecular dynamics simulation, we aim to characterize ion behavior adjacent to hydrophobic organic phases. Concerning natural environments, NaCl, CaCl2 and Na2SO4 electrolytes at low (5 wt%) and high (15 wt%) concentrations were brought in contact with heptane and/or toluene which account for aliphatic and aromatic constituents of typical crude oils, respectively. The reproduced experimental data for interfacial tension, brines density and ions’ diffusivities adequately verify our molecular calculations. FindingsIons accumulate nearby the intrinsically charge-neutral oil surfaces. A disparate surface-favoring propensity of ions causes the interfacial region to resemble an electrical layer and impose an effective surface charge onto the oil surface. Despite absence of any polar site, the effective surface charge density is hydrocarbon-dependent, with the highest and lowest values observed for toluene and heptane interfaces, respectively. Due to accumulation of toluene molecules nearby the brines, the interfacial characteristics of heptol (toluene-heptane mixture) is comparable to that of the toluene phase.

Lignin Contribution to Aliphatic Constituents of Humic Acids through Fungal Degradation

To investigate how fungi transform lignin in soil during humification, a naturally brown‐rotted wood was subjected to additional fungal degradation by the white‐rot fungus Phanerochaete chrysosporium. Both Fourier transform infrared spectroscopy and ultrahigh resolution mass spectrometry showed that fungal degradation, an integral part of the soil humification process, transformed lignin‐derived aromatic molecules and simultaneously created many new aliphatic molecules. The majority of these new aliphatic molecules were chemically different from aliphatic molecules already existent in the lignin precursor extract and in the P. chrysosporium biomass. Our results strongly suggest that humification by white‐rot fungi in soil transforms lignin to humic substances with a predominant aliphatic character. This challenges the concept that only aromatic structures are expected from humification of lignin by fungi. This finding also reverses current views that aliphatic constituents of soil humic materials are not principally derived from lignin.Core Ideas ESI‐FTICR‐MS analysis opens a new window for examining the fate of lignin in nature. Fungi play an important role in humification of plant material in soil. Formation of aliphatic molecules from lignin via fungal degradation is observed.

An investigation of the acute central nervous system effects of n-decane

Acute central nervous system (CNS) depression is the most sensitive toxicological effect associated with aliphatic hydrocarbon exposure. No observed effect levels for the CNS effects of aliphatic constituents decrease with increasing carbon number to C10 (Lammers et al., 2011; McKee et al., 2011), whereas constituents with carbon numbers > C10 do not produce CNS effects at maximally attainable vapor concentrations (Nilsen et al., 1988). Accordingly, as n-decane appeared to be the “worst case” for acute CNS effects among aliphatic hydrocarbon solvent constituents, experimental studies were conducted to more precisely define the no effect level. Rats were exposed for 8 h to n-decane, either constantly at 3000 mg/m3 or at higher levels using a discontinuous exposure protocol to assess the influence of fluctuating exposures. Neurobehavioral testing methods including visual discrimination performance and motor activity were used to assess performance, and concentrations of n-decane in blood and brain were measured to obtain pharmacokinetic data. No statistically significant differences were observed in the neurobehavioral tests, establishing 3000 mg/m3 as the no effect level for CNS effects in rats. These data support the recommended guidance value of 1050 mg/m3 for C9–C15 aliphatic hydrocarbons for use in calculating occupational exposure levels for complex hydrocarbon solvents and provide empirical evidence that advice from the ACGIH® that within a working day there should be no more than 3 fluctuations, not longer than 15 min and not exceeding 3 times the Threshold Limit Value (TLV®), is reasonable for this group of substances.

Isolation and characterization of bacillus amyloliquefaciens 6A: A novel kerosene oil degrading bacterium

Abstract Bacillus amyloliquefaciens 6A, isolated from kerosene contaminated industrial wastewater, could remove 13, 39, 40 and 64% kerosene oil as compared to the microorganisms indigenously present in the industrial effluent which could degrade only 14, 16, 27 and 28% kerosene oil after 2, 4, 6 and 8 days, respectively. Kerosene biodegradation behavior was evaluated by studying biodegradation kinetics, half-life and thermodynamics to determine the suitability of the process. Kerosene biodegradation process followed pseudo first order kinetics and found greatly influenced with temperature. Moreover, extracellular lipase activity was calculated and relationship between concentration of kerosene oil and enzyme activity (oil degradation) was established by Michaelis–Menten plot. The enzyme followed the single substrate Michaelis–Menten kinetics with Vmax (maximum rate) 9.251 ( μ g/ml)/min and Km (Michaelis constant, substrate affinity) 8.325 μ g/ml for kerosene oil. Furthermore, kerosene hydrocarbon fractions before and after bacterial treatment were estimated by GC–MS and TLC which revealed the degradation of many aliphatic and aromatic hydrocarbon constituents of kerosene. It is the first Gram positive bacterium reported from Pakistan which can transform long chained hydrocarbons (C11–C34) into small metabolites. In conclusion, bacterial strain has proved cost-effective, proficient and a very expedient tool in green chemistry to decontaminate environmental hydrocarbon pollutants.

Fast pyrolysis of hot-water-extracted and delignified Norway spruce (Picea abies) sawdust by Py\u2013GC/MS

The thermochemical behavior of Norway spruce (Picea abies) sawdust as such and after various chemical treatments (hot-water extraction, delignification, and hot-water extraction followed by delignification) was investigated by analytical pyrolysis–gas chromatography–mass spectrometry. In each case, the yields of major GC-amenable condensable products were semi-quantitatively measured, and the individual compounds were classified into several compound groups. The formation of these groups from feedstock samples with varying mass portions of their structural constituents (carbohydrates and lignin) was determined at 500 °C and 700 °C with a residence time of 5 s and 20 s. The formation of pyrolysis products was shown to be characteristically dependent on feedstock composition as well as on pyrolysis conditions. This kind of approach was of practical importance with respect to efforts not only to develop rapid characterization tools for lignocellulosics, but also to uncover new biorefinery possibilities to produce bio-oils, for example, enriched either with aliphatic or aromatic constituents.

Mulching-induced preservation of soil organic matter quality in a burnt eucalypt plantation in central Portugal

Mulching has amply proven its effectiveness to mitigate post-fire soil erosion but its impacts on soil organic matter (SOM) quality and quantity continue poorly studied. The present study addressed this knowledge gap for a eucalypt plantation in central Portugal that had been burnt and, immediately after the wildfire, mulched with 13.6 Mg ha−1 of eucalypt logging residues some five years before. This was done by performing a range of analytical techniques (elemental and isotope analyses, analytical pyrolysis and 13C NMR spectroscopy) not only on the bulk soil samples but also on their humic acids (HAs) and free organic matter (FOM) fractions. While mulching reduced soil and SOM losses with 91 and 93%, respectively, it also improved SOM quality of the topsoil, in particular in terms of HAs and FOM. At 0–4 cm depth, both HAs and FOM contents were roughly twice as high in the mulched plots as in the control plots. The effects of mulching on the molecular composition of HAs and FOM fractions, however, varied markedly. Analytical pyrolysis (Py-GC/MS) revealed that mulching had led to a noticeable accumulation of labile, aliphatic SOM constituents such as carbohydrate-derived and alkyl compounds (fatty acids and n-alkanes) but that it hardly affected the composition of HAs. Even so, solid-state 13C NMR spectroscopy showed that mulching had resulted in a relative increase in aryl C in the FOM fraction, suggesting an enhanced preservation of the pyrogenic OM. Overall, the combined use of a range of analytical techniques allowed to conclude that, five years after their application, the forest logging residues had led to a greater preservation of the fire-derived pyrogenic OM (mainly aromatic compounds) in the topsoil as well as to higher contents of SOM's most labile molecular constituents (mainly carbohydrates and n-alkyl compounds). The former reflected the reduced erosion rates, while the latter was probably due to a combination of reduced erosion rates with the additional input of fresh organic matter.

New aliphatic ester constituents of Hygrophila auriculata (K. Schum) Heine from the Koshi river basin

This research is meant for the isolation of the compounds out from the methanolic extract of the Hygrophila auriculata. This herb was customarily used as a diuretic to cure the inflammation, pain, urinal infections, and the gout. To isolate the compounds from methanolic extract of Hygrophila auriculata which was taken from Bihar’s Koshi river belt, open silica gel column chromatographic methods with different solvent mixtures were applied. The elucidation of the structure of the different separated phytoconstituent was accomplished through spectral data analysis, chemical reactions and their literary comparisons. Phytochemical analysis of methanolic extract of Hygrophila auriculata gave a new compound identified as n-octa-triacontan-3-one-19α, 31α-diol (4) and along with the four known aliphatic ester compounds n-hexacos-21-one-1-ol (1), trans-tetracont-7-en-1-ol (2), n–octacosan-8-one (3) and n-heptacosan-11α-ol (5). A new compound was found with four other known compounds as aliphatic esters from H. auriculata extract.

Indoor and outdoor air concentrations of volatile organic compounds in schools within different urban areas

This study included nine schools which were selected from three different areas (industrial, traffic, and residential) of Kuwait. Three schools were chosen from each area to represent elementary, middle, and secondary levels. Samples of indoor volatile organic compounds (VOCs) were collected using canisters placed in one classroom in each school in addition to outdoor VOCs captured in canisters placed at the roof of one chosen school among the three studied at each area. The VOCs levels were monitored during the weekdays and weekends (schools closed) over a period of 2 months. The results showed higher VOCs concentrations in indoor than in outdoor samples in all schools studied at the three areas during both the weekdays and the weekends, irrespective of the level of schooling. Indoor VOCs concentrations were less than 200 ppbv in all schools, with relatively higher levels recorded in schools located in the industrial area reaching 681 ppbv since the indoor air quality is influenced by that of outdoor. The total (indoor and outdoor) levels of VOCs measured during the weekdays were higher than those detected in the weekends in both the traffic and industrial areas, whereas the opposite was observed in the residential area due to its increased weekend traffic density. Percentage composition of VOCs in air samples indicated domination of halogenated and oxygenated components compared to aliphatic and aromatic constituents. The affected schools should increase ventilation rates and install devices to purify the indoor air to ensure healthy environment for students, teachers, and employees at schools.

Essential Oils and Their Bioactive Compounds in the Control of Gastrointestinal Nematodes of Small Ruminants

Background: Gastrointestinal nematodes are one of the major health and economic problem of sheep and goats in the world. The control of these nematodes is carried out conventionally with synthetic anthelminths, which favored the selection of gastrointestinal nematode (GIN) populations multiresistant to anthelmintics. The emergence of anthelmintic resistance has stimulated the search for new alternatives to control small ruminant GIN, standing out the use of plants and their bioactives compounds, such as essential oils (EO). The objective of this review was to present the main characteristics and anthelmintic activity of EO, their isolated compounds and drug delivery systems in the control of GIN.Review: Essential oils are a complex blend of bioactive compounds with volatile, lipophilic, usually odoriferous and liquid substances. EO are composed of terpenes, terpenoids, aromatic and aliphatic constituents. EO has various pharmacological activities of interest in preventive veterinary medicine such as antibacterials, antifungals, anticoccicids, insecticides and anthelmintics. In vitro and in vivo tests are used to validate the anthelmintic activity of EO on GIN. In vitro tests are low cost screening tests that allow the evaluation of the anthelmintic activity of a large amount of bioactive compounds on eggs, first (L1) and third stage larvae (L3), and adult nematodes. The antiparasitic effect of EO is related to its main compound or to the interaction of the compounds. These bioactive compounds penetrate the cuticle of the nematodes by transcuticular diffusion, altering the mechanisms of locomotion, besides causing cuticular lesions. Following in vitro evaluation, the acute and sub-chronic toxicity test should be performed to assess the toxicity of the bioactive compounds and to define the dose to be used in in vivo tests. In vivo tests are more reliable because the anthelmintic effectiveness of bioactive compounds is evaluated after the metabolization process. The metabolization process of the bioactive compounds can generate metabolites that exhibit or not anthelmintic effectiveness. The in vivo tests assessing the anthelmintic effectiveness of bioactive compounds in sheep and goats are the fecal egg count reduction test and the controlled test. OE promoted reduction of egg elimination in faeces which may be related to cuticular and reproductive alterations in GIN, and reduction of parasite burden in in vivo tests. Due to the promising results obtained with OE in the in vivo tests, interest has been aroused in using nanotechnology as an alternative to increase the bioavailability of OE and consequently, potentializing its anthelmintic effect, reducing the dose and toxicity of the biocompounds. In addition to nanotechnology, the isolation and chemical modification of compounds isolated from OE have been employed to obtain new molecules with anthelmintic action and understand the mechanism of action of EO on the small ruminant GIN.Conclusion: The use of EO and their compound bioactive in the control of resistant populations of GIN is a promising alternative. The adoption of strategies in which natural products can replace synthetic anthelmintics, such as in dry periods and use synthetic anthelmintics in the rainy season when the population in refugia in the pasture is high, thus reducing the dissemination of GIN resistant populations. As perspective, the evaluation of pharmacokinetics and pharmacodynamics of these natural products should be performed so that one defines treatment protocols that optimize the anthelmintic effect.

Bio-efficacy of Ruta graveolens Essential Oil and Its Long Chain Aliphatic 2-Methlyl Ketone Constituents on the Egg Hatchability of Corcyra cephalonica (Stainton)

Plant essential oils are comprised of complex mixtures of components including minor constituents which determine the characteristic aroma and odour of the plant in contrast to synthetic insecticides based on the single products that act synergistically within plant as a defense strategy against herbivory and thus, it is likely that they are more durable towards evolving pest resistance. Hence, due to the evolutionary relationship with their functional roles and largely environmental friendly nature, these natural pesticides could be efficiently harnessed by the farmers in developing countries like Sri Lanka for post-harvest insect pest management. In that context, the present study was undertaken to assess the impact of the essential oil of Ruta graveolens and its long chain aliphatic 2-methyl ketone constituents (2-octanone, 2-nonanone, 2-decanone, 2-undecanone, 2-dodecanone and 2-tridecanone)on the egg hatchability of rice moth (Corcyra cephalonica), which is a serious lepidopteran pest of stored cereals, by exposing freshly laid eggs for various exposure time durations (6 hrs, 12 hrs and 24 hrs) in contact bioassays with different authentic concentrations under the laboratory conditions (29±20C and 84±2% R.H.). The concentrations of essential oil and its ketone constituents applied and the exposure time periods were significantly influenced the percentage egg hatchability of C. cephalonica. Accordingly, the inhibitory activity of egg hatching was significantly increased with increasing concentrations and time periods of exposure. Essential oil of R. graveolens at the concentration of 0.204 μl cm-2 and the even-chained congeners at the corresponding authentic concentrations (0.0009-0.0045μl cm-2) brought about 100% inhibition of hatching. Moreover, odd-chained congeners produced egg hatchability inhibition levels ranging from 60-90 % with the corresponding authentic concentrations (0.002-0.046μl cm-2) after 24 hr exposure time duration. Based on LC50 values, the eggs were significantly more susceptible to even-chained congeners (LC50= 0.00002 – 0.0015μl cm-2) than to the odd-chained congeners (LC50= 0.00008 – 0.0084μl cm-2) and the essential oil (LC50= 0.0096 μl cm-2). Regression equations and the probability values of lethal concentrations of essential oil and its ketone constituents revealed a significant and positive role in the population inhibition of C. cephalonica. The present study demonstrates the potential of R. graveolens essential oil and its ketone analogues to be exploited as natural grain protect ants which is of immense significance in view of overcoming or reducing environmental and toxicological implications of the unsystematic use of synthetic pesticides. Keywords: Corcyra cephalonica, Egg hatchability, Essential oil, Long chain aliphatic 2-methyl ketones, Ruta graveolens

Nuclear Magnetic Resonance Analysis of Changes in Dissolved Organic Matter Composition with Successive Layering on Clay Mineral Surfaces

Dissolved organic matter (DOM) chemistry and the potential for organic matter (OM) to self-associate with other OM components are important aspects of understanding the mechanisms of DOM sorption to clay surfaces. To investigate this further, we sorbed DOM isolated from peat humic acid onto either kaolinite, montmorillonite and gibbsite via ten sequential batch equilibration sorption experiments. Dissolved organic carbon (DOC) sorption to all minerals increased consistently, suggesting that sorption occurred via mineral-OM interactions at the beginning of the experiment. After six successive DOM loadings, the concentration of DOC sorbed by kaolinite and gibbsite began to plateau, likely due to the saturation of mineral surface sorption sites. Solution-state nuclear magnetic resonance (NMR) analysis of unbound DOM showed that kaolinite and montmorillonite sorbed aliphatic, protein and lignin components initially and primarily aliphatic and aromatic constituents in later sorption experiments, whereas gibbsite sorbed mostly aliphatic compounds during all DOM loadings. Analysis of the organo-clay complexes using 1H high resolution–magic angle spinning (HR-MAS) NMR confirmed the preferential sorption of aromatic and aliphatic components to all three minerals. Overall, these results suggest that OM-OM interactions may be important mechanisms of DOM sorption to clay mineral surfaces.

New aliphatic constituents from the aerial parts of Artemisia annua L.

Artemisia annua L. (Asteraceae) is an aromatic annual herb, up to 2 m in height, found in temperate Asia, especially China and naturalized in many countries of the world. The plant is prescribed against fever, malaria, skin diseases, jaundice, malignant ulcers and haemorrhoids. Phytochemical investigation of the aerial parts of A. annua led to the isolation of alkyl alcohols, fatty acid esters, alkyl glucoside and fatty acids characterized as n- nonadecan-2β-ol (isononadecanol, 1 ), n- docosan-9β-ol (isodocosanol, 2 ), 1 - octacosanol ( n- octacosanyl alcohol, 3 ), n -heptadecanyl n -octadec-9,12-dienoate ( n -heptadecanyl linoleate, 4 ), n -octadecanyl n- octadec-9,12,-dienoate ( n -octadecanyl linoleate, 5 ), n -nonacosanyl n -octadec-9, 12-dienoate ( n -nonacosanyl linoleate, 6 ), n -cos-(Z)-10-enoic acid ( cis -cos-10-enoic acid, 7 ), n -cos-(Z)-9-enoic acid ( cis-c os-9-enoic acid , 8 ) and n- heptadecanyl-s-D-glucopyronoside ( n -heptadecanyl glucoside, 9 ). The structures of all phytoconstituents, isolated for the first time from A. annua have been elucidated on the basis of spectral data analysis and chemical reactions

Essential Oil Constituents of Phlomis pungens Willd. from Azerbaijan

The GC-MS analyses of the essential oils of inflorescence of Phlomis pungens Willd. (Lamiaceae), collected from Galalti, Altiagach and Nakhchivan of Azerbaijan, led to the identification of 2 monoterpenes, 44 sesquiterpenes, 1 diterpene and 4 aliphatic acids constituents accounting for over 93.9, 94.1 and 95.2% of the total oils. In the same way the GC-MS analyses of the essential oils of leaves collected from three localities led to the identification of 2 monoterpenes, 37 sesquiterpenes, 1 diterpene and 4 aliphatic acid constituents, too which responsible for over 90.3, 92.4 and 94.8% of the total oils. Non surprisingly, the main constituents of inflorescence and leaves oil were sesquiterpenes (mainly non-oxygenated) and aliphatic acids which these findings are consistent with previous studies on Phlomis genus. Quantitative and qualitative differences were found among essential oils of inflorescence and leaves of the plants collected from different localities of Azerbaijan.