Wax Lipids from Leaf Surfaces of Some Common plants of Malaysia

Epicuticular wax lipids from leaves of some common plant species found in the Klang Valley, Malaysia were extracted into dichloromethane for analysis. Extracts were separated into hydrocarbon, carboxylic acid, ketone and alcohol fractions. The fractions after derivatization were then subjected to gas chromatographic (GC) and gas chromatography-mass spectrometric (GC-M5) analyses. The wax yield was highest for Mestta ferrea while the lowest yield was obtained from Eugenia gran dis. In most species studied the m~or n-alkane was found to be hentriacontane (C31 ), followed by tritriacontane (C,,) and nonacosane (C",) , respectively. The n-alkanes exhibit a saw-tooth pattern which is characteristic of a biogenic origin. A strong even-to-odd carbon number predominance is observed for both the n-alkanoic acids and 1)alkanols. Only traces of mainly B-sitosterol were detected in some of the species. The triterpenoids and triterpenes were mostly found in the wax of Mesua ferrea with «- and p-boswellic acids as the major components and minor amounts of «- and p-amyrin. Other biomarkers identified were «and p-amyrones, friedelin, friedelanol, friedelane, olean-12-ene, taraxerene, squalene, dihydronyctanthic acid, dihydroroburic acid and dihydrocanaric acid. This study has shown that the distribution of n-alkanes is a function of the ambient temperature

Environmental factors controlling the distributions of Botryococcus braunii (A, B and L) biomarkers in a subtropical freshwater wetland

Here we report the molecular biomarker co-occurrence of three different races of Botryococcus braunii (B. braunii) in the freshwater wetland ecosystem of the Florida Everglades, USA. Thespecific biomarkers include C32–C34 botryococcenes for race B, C27–C32 n-alkadienes and n-alkatrienes for race A, and lycopadiene for race L. The n-alkadienes and n-alkatrienes were present up to 3.1 and 69.5 µg/g dry weight (dw), while lycopadiene was detected in lower amounts up to 3.0 and 1.5 µg/g dw in periphyton and floc samples, respectively. Nutrient concentrations (P and N) did not significantly correlate with the abundances of these compounds. In contrast, n-alkadienes and n-alkatrienes were present in wider diversity and higher abundance in the floc from slough (deeper water and longer hydroperiod) than ridge (shallower water and shorter hydroperiod) locations. n-Alkadienes, n-alkatrienes, and lycopadiene, showed lower δ13C values from −40.0 to −35.5‰, suggesting that the source organisms B. braunii at least partially utilize recycled CO2 (13C depleted) produced from OM respiration rather than atmospheric CO2 (13C enriched) as the major carbon sources

Variations in δ13C values of levoglucosan from low-temperature burning of lignite and biomass

Levoglucosan, an anhydrosaccharide, is commonly used as an organic tracer for biomass burning, but has also been identified from coal smoke particulate matter (PM) including lignites. Here we showed that stable carbon isotope analysis specifically of levoglucosan may be one possible way to determine the relative contributions from coal combustion versus biomass burning sources. PM sampleswere collected from low-temperature burning/ smoldering of Miocene lignites from Poland and basket willow (Salix viminalis L.) representative of biomass. The calculated levoglucosan δ13C values of xylites varied from −23.6 to−21.6‰, while for detritic coal samples they ranged from −24.2 to −23.1‰, with means of −22.7 and −23.7‰, respectively. The calculated levoglucosan δ13C value of basketwillow woodwas−27.1‰. Values ofwillowwoodmixtureswith xylite varied from−25.8 to−23.4‰(with an increasing proportion of xylite), while values of mixtures of willow and detritic coal ranged from−26.9 to−24.6‰(with an increasing proportion of detritic coal). The δ13C values for themixtures changed proportionally to the contents of individual components with R2=0.88 and 0.89 for willow with xylite and detritic coal, respectively. The hopanoid distributions characteristic for low-temperature lignite/peat burning, with a predominance of 22R-α,β-homohopane, ββ-hopanes and hopenes, as well as low or very low values of the homohopane index,were observed in smokePMfrommost lignite samples and absent in the basket willow sample. Thus, the relatively high content of hopanes (with the occurrence of 22R-α,β-homohopane, ββ- hopanes and hopenes) in atmospheric PM samples can be treated as additional tracers of lignite combustion

Organic compounds in biomass smoke from residential wood combustion: Emissions characterization at a continental scale

Wood smoke in the atmosphere often accounts for 20–30% of the ambient fine-particle concentrations. In communities where wood is burned for home heating, wood smoke can at times contribute the majority of the atmospheric fine-particle burden. Chemical mass balance receptor models that use organic compounds as tracers can be used to determine the contributions of different emission sources, including wood smoke, to atmospheric fine-particle samples. In order for organic chemical tracer techniques to be applied to communities across the United States, differences in wood smoke composition that arise from differences in the type of wood burned in various regions must be understood. A continental-scale accounting of particulate organic compound emissions from residential wood combustion has been constructed which helps to quantify the regional differences in wood smoke composition that exist between different parts of the United States. Data from a series of source tests conducted on 22 North American wood species have been used to assemble a national inventory of emissions for more than 250 individual organic compounds that are released from wood combustion in fireplaces and wood stoves in the United States. The emission rates of important wood smoke markers, such as levoglucosan, certain substituted syringols and guaiacols, and phytosterols vary greatly with wood type and combustor type. These differences at the level of individual wood type and combustion conditions translate into regional differences in the aggregate composition of ambient wood smoke. By weighting the source test results in proportion to the availability of firewood from specific tree species and the quantities of wood burned in each locale, it is possible to investigate systematic differences that exist between wood smokes from different regions of North America. The relative abundance of 10 major wood smoke components averaged over the emissions inventory in different regions of the United States is computed and then used to illustrate the extent to which wood smoke composition differs from region to region in North America

Lipid/bitumen maturation by hydrothermal activity in sediments of Middle Valley, leg 139

The accelerated diagenesis, maturation, and catagenesis of organic matter to hydrothermal petroleum was studied in sediments from Ocean Drilling Program Leg 139 in Middle Valley, northern Juan de Fuca Ridge. Sediments at Sites 855 and 856 have experienced high heat flow resulting in accelerated diagenesis of the immature organic matter without product migration. Ruid migration through these sediments has resulted in an influx of mature organic components, yielding diverse bitumen mixtures. At Site 857 the alteration has occurred in situ to the catagenetic stage and at Site 858, the hottest holes, the hydrothermal petroleums have migrated after generation. Maturation for the rc-alkanes proceeds from high CPI values to 250 dalton)

Saccharides in atmospheric particulate and sedimentary organic matter : status overview and future perspectives

Saccharides are omnipresent compounds in terrestrial and marine ecosystems. Since the 2000s, their role in environmental and geochemical studies has significantly increased, but only anhydrosaccharides (mainly levoglucosan) have been reviewed. Here we present the wider knowledge about saccharides in organic matter of aerosols, bottom sediments, soils, dust, and sedimentary rocks. The main purpose here is to characterize the possible sources of saccharides, as well as sacharol formation, seasonal variability, and the possible applications in environmental and paleoenvironmental interpretations. Different saccharide sources were designated, including biomass burning, and particulate matter such as pollen, spores, lichen, and fungi, as well as polysaccharide decomposition as possible inputs of monosaccharides. The main focus was on the most common saccharides encountered in environmental samples and sedimentary rocks. These are the mono- and disaccharides glucose, fructose, sucrose, and trehalose, and sacharols arabitol and mannitol. The anhydrosaccharides levoglucosan, mannosan, and galactosan were evaluated as ancient wildfire indicators and industrialization tracers found in lacustrine sediments starting from Pleistocene to contemporary deposits. However, other anhydrosaccharides like xylosan and arabinosan were also found as products of fossil wood burning. These anhydrosaccharides have the potential to be further tracers of hemicellulose burning. Additional recommendations are proposed for future research, including environmental and paleoenvironmental topics that need to be addressed

Origin and significance of saccharides during initial pedogenesis in a temperate climate region

Saccharides are common constituents of soils, but their role and origin in the initial phases of pedogenesis remain unclear. Here we show the detailed composition of neutral sugars extracted from arenosols at different development stages, combined with additional lipids of diverse origins using gas chromatography-mass spectrometry (GC–MS). During the first stage (I) of development sucrose is the most abundant saccharide in the soil crust at up to 45,000 μg/g TOC. Sucrose is also the predominant compound in the second and third development stages, but its concentration decreased to the range of 1600 to 16,000 μg/g TOC. Stages II and III of soil development were characterized by a gradual increase in arabitol, mannitol and trehalose, compounds typical for fungi and lichen. Their abundances increased from several percent (compared to the major sucrose) to 10–32% for mannitol and 34–54% for trehalose. Moreover, in stage III there was a considerable increase in the contents of the saccharides: pinitol, myo-inositol, scyllo-inositol, arabinose, together with non-sugar compounds: dehydroabietic acid, p-hydroxybenzoic acid, gallic acid and sitosterol. All these latter compounds are higher plant markers, mainly derived from conifer detritus. The relationships between the ratios of trehalose/sucrose vs. (mannitol + arabitol)/sucrose and TOC vs. (mannitol + arabitol)/sucrose differentiated precisely the top soil layer of arenosols which are covered by different stages of biological soil crust. Our study shows that free sugars, supplemented by lipid biomarkers and total organic carbon contents, are good indicators of soil in the initial phase of pedogenesis

Global comparisons of organic matter in sediments across the Cretaceous/Tertiary boundary

The Cretaceous/Tertiary (K/T) boundary is marked by extensive changes in the sedimentary fossil record of continental and marine life. Organic matter in sediments from above and below the K/T boundary has been studied to identify consequences of the biotic extinctions and of the changes in biological productivity which occures at this time. Data from locations encompassing a variety of marine paleoenvironments were examined to assess the gl;obal extent and local expressions of these biological changes. Characterizations of organic included Rock-Eval pyrolysis, stable carbon isotope ratios, and distributions of extractable biomakers. In general, organic carbon concentrations are a few tenths of a percent in the chalks and marls above and below the K/T boundary; in some boundary clay samples concentrations up to 5% are found. The elevated amounts near the boundary result from oxidation of marine organic matter, consequent dissolution of carbonates, and concentration of the surviving organic matter. At all locations, the organic matter has been microbially reworked and evidently was deposited in oxidizing environments. Carbon isotope shifts in open marine sediments suggest biological productivity was depressed following the K/T boundary. Repetition of these changes at different verifies the global extent of the boundary event, yet local variations in its expression are evident.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/28909/1/0000746.pd

Dissolved organic carbon in interstitial waters from sediments of Middle Valley, leg 139

High-temperature combustion oxidation measurements of nonvolatile dissolved organic carbon (DOC) have been determined for pore waters from sediments of Middle Valley, Ocean Drilling Program Leg 139, as well as for overlying and near-bottom seawater. The DOC values in the interstitial waters are generally greater than those in the overlying water column, ranging from 0.1 to 86 mg/L of carbon. Some of the profiles of DOC in the pore waters are similar to total organic carbon, total carbon, and total inorganic carbon profiles. At Site 855 the concentrations of DOC in interstitial waters generally decrease with depth. DOC maxima at shallow depths of Site 858 are probably enriched due to higher temperature alteration of organic matter. At Sites 856 and 857, besides the decreasing trend above, the DOC increases at greater depths, also due to the hydrothermal activity. The values of DOC correlate with MnO and MgO profiles in Hole 856B. The changes below 30 mbsf in the DOC depth profiles of Site 858 parallel those of the volatile hydrocarbon gases

Sugars as source indicators of biogenic organic carbon in aerosols collected above the Howland Experimental Forest, Maine

Author Posting. © The Authors, 2005. This is the author's version of the work. It is posted here by permission of Elsevier B.V. for personal use, not for redistribution. The definitive version was published in Atmospheric Environment 40 (2006): 1694-1705, doi:10.1016/j.atmosenv.2005.11.001.Bulk aerosols (> 1 μm) were collected continuously above the canopy at the Howland Experimental Forest, Maine, USA from May to October 2002. Each sample integrated over an approximately two-week period. Mono- and disaccharide sugars were extracted using a microscale technique and were analyzed as their TMS derivatives by GC-MS. Concentrations of total aerosol sugars ranged from 10 to 180 ng m-3. Glucose was the most abundant sugar (40-75% of the total sugars). The monosaccharides arabinose, fructose, galactose, mannose, arabitol and mannitol, and the disaccharides sucrose, maltose and mycose (aka trehalose) were also present in lower concentrations. The sugar composition in the aerosols varied seasonally. Fructose and sucrose were prevalent in early spring and decreased in relative abundance as the growing season progressed. Sugar polyols (arabitol and mannitol) and the disaccharide mycose (a fungal metabolite) were more prevalent in autumn during the period of leaf senescence. The changes in the sugar composition in the aerosol samples appear to reflect the seasonality of sugar production and utilization by the ecosystem. Plant waxes were present as significant components also indicating an input from biogenic background. Smoke plumes from Quebec forest fires passed over the Howland site in early July 2002. Levoglucosan, a biomarker of biomass burning, increased by an order of magnitude in the aerosol samples collected during this time. Glucose, mannose, arabinose, galactose, and also, plant waxes increased in concentration by factors of 2-5 in the smoke-impacted samples, indicating that wildfires enhance atmospheric emissions of uncombusted organic compounds. In contrast, concentrations of fructose, sugar polyols and disaccharides were not significantly higher in the smoke-impacted samples and indicated that biomass burning was not a significant source of these compounds in the aerosols.This work was funded by a grant to MHC (DOE-NIGEC Grant 15460100) from the U.S. Department of Energy’s (DOE) National Institute for Global Environmental Change (NIGEC), through the NIGEC Northeast Regional Center at Harvard University