Rich Carbon Source Research Articles

Synthesis of carbon nanotubes from conventional biomass-based gasification gas

The gas product which synthesized from the biomass-based gasification process is a kind of rich carbon source gas. To establish the high-value applications, the synthesis process of carbon nanotubes (CNTs) from biomass-based gasification gas is established in this study. This study focused on the CNTs production process from the mixture of CO and CH4, which were primary components of biomass pyrolysis/gasification gas, in a thermogravimetric and a fluidized bed. The reaction temperature and the partial pressure of the essential role of the mixture gas were investigated. Meanwhile, in the fluidized bed, results of the decomposition of mixture gas (CO/CH4) were compared with the results by pure gas (CH4 decomposition process and CO disproportionation process). Results showed that the initial temperature for carbon weight gain increased in the mixture gas decomposition process was lower than that of the pure CH4 decomposition process in the TG reactor. In the fluidized bed, the conversions of CO and CH4 were promoted in the mixture gas decomposition process. CO and CH4 played a synergistic role with the H2 as the medium in the CO/CH4 decomposition process. With the increase of CO/CH4 partial pressure ratio, the yield and quality of CNTs increased significantly. The CNTs produced from CO/CH4 were longer and smoother than that of CH4 and CO decomposition. When the partial pressure ratio of CO/CH4 up to 2, the yield of carbon weight gain was eight times than that of same partial pressure of CH4 decomposition. Therefore, it is feasible for the decomposition of biomass-based gasification gas for the CNTs formation process.

Isolate new microalgal strain for biodiesel production and using ftir spectroscopy for assessment of pollutant removal from palm oil mill effluent (pome)

In tropical countries, the palm oil industry discharges a large amount of wastewater. The wastewater can serve as an economical nutrient source or substrate that can support the cultivation of microalgae. This study aimed to identify the local species of microalgae potentially existing in the industrial wastewater of palm oil mill effluent (POME). POME was selected as the key source of waste due to its higher potential in producing lipids from microalgae as biofuel substrate. A novel green microalgal strain was isolated from POME of Kahang- Johor west palm oil mill in Malaysia and was identified as Chlamydomonas sp. and subsequently named UTM 98 with Catalogue No. of KR349061. This study emphasised the effectiveness of POME as the main carbon source to maintain the growth of microalgae and simultaneously to increase the lipid content. In this study, Fourier Transform Infrared spectroscopy (FTIR) and Gas Chromatography (GC-FID) were used to identify andquantify lipids in the freshwater microalgae. Cultivation of microalgae were initially carried out in 250 mL Erlenmeyer flask containing 100 mL medium at ± 30 °C with continuous illumination (± 14 µmol-1 m-2 s-1) andup to 20 d of cultivations. Results demonstrated that on the chromatogram, the highest retention achieved is belong to palmitic acid (C16:0). Chlamydomonas incerta (C. incerta) species is found to contain shorter chain fatty acids, mainly 16 - 18 carbon length, which is ideal for biodiesel production. FTIR spectrum of POME treated biomass displayed the shifting of peak at 591 cm-1 and also removal of C-Cl stretching. The spectrum of POME effluent treated biomass revealed broad peak at 3,430 cm-1. The results of SEM micrographs showed that, after treating POME with C. incerta, the cells became slightly rough and corrugated textures and some particles were found on the surface of the cell wall. Using POME as a rich carbon and nutrient source is also a promising approach either as natural environment treatment or as high-lipid-content raw material for production of biofuel.

Streptomyces clavuligerus strain selection for clavulanic acid biosynthesis: a study based on culture composition effects and statistical analysis

La importancia clínica e industrial del ácido clavulánico (AC) promueve la búsqueda de nuevas estrategias para aumentar su productividad a un menor costo. En esta contribución, se evaluó la producción de AC en dos cepas de referencia de Streptomyces clavuligerus (Sc), ATCC27064 y DSM41826; éstas se probaron en diferentes medios de cultivo; los rendimientos de producto y costo de los medios se usaron como criterios de selección. En promedio, ScATCC alcanzó una concentración de AC 1.6-veces mayor que ScDSM, en el medio de proteína de soya (ISP). Se optimizó el medio con un diseño experimental central compuesto, estudiando la influencia del ISP y K2HPO4 sobre la producción de AC. La concentración máxima de AC obtenida en el medio optimizado (56mg·L-1) estuvo cerca del óptimo teórico. Nuestros resultados confirman que medios de cultivo con fuentes de carbono como glicerol y/o almidón proporcionan las mejores condiciones para la producción de AC.

Loving the poison: the methylcitrate cycle and bacterial pathogenesis.

Propionate is an abundant catabolite in nature and represents a rich potential source of carbon for the organisms that can utilize it. However, propionate and propionate-derived catabolites are also toxic to cells, so propionate catabolism can alternatively be viewed as a detoxification mechanism. In this review, we summarize recent progress made in understanding how prokaryotes catabolize propionic acid, how these pathways are regulated and how they might be exploited to develop novel antibacterial interventions.

Synthesis of hydrophilic and hydrophobic carbon quantum dots from waste of wine fermentation.

Wine lees are one of the main residues formed in vast quantities during the fermentation of wine. While toxic when applied to plants and wetlands, it is a biodegradable material, and several alternatives have been proposed for its valorization as: dietary supplement in animal feed, source for various yeast extracts and bioconversion feedstock. The implementation of stricter environment protection regulations resulted in increasing costs for wineries as their treatment process constitutes an unavoidable and expensive step in wine production. We propose here an alternative method to reduce waste and add value to wine production by exploiting this rich carbon source and use it as a raw material for producing carbon quantum dots (CQDs). A complete synthetic pathway is discussed, comprising the carbonization of the starting material, the screening of the most suitable solvent for the extraction of CQDs from the carbonized mass and their hydrophobic or hydrophilic functionalization. CQDs synthesized with the reported procedure show a bright blue emission (λmax = 433 ± 13 nm) when irradiated at 366 nm, which is strongly shifted when the wavelength is increased (e.g. emission at around 515 nm when excited at 460 nm). Yields and luminescent properties of CQDs, obtained with two different methods, namely microwave and ultrasound-based extraction, are discussed and compared. This study shows how easy a residue can be converted into an added-value material, thus not only reducing waste and saving costs for the wine-manufacturing industry but also providing a reliable, affordable and sustainable source for valuable materials.

Comparison of hydrochemistry and organic compound transport in two non-glaciated high Arctic catchments with a permafrost regime (Bellsund Fjord, Spitsbergen)

An increase in air temperature related to climate change results in the retreat of glaciers, the degradation of permafrost, and the expansion of glacier-free areas in the polar regions. All these processes lead to changes in the Arctic landscape. They influence the hydrochemistry of streams and rivers fed by glaciers and thawing permafrost. In this study, we examine eighty two water samples from two non-glaciated catchments with snow-permafrost regime: the Tyvjobekken Creek and the Reindeer Creek (NW Wedel-Jarlsberg Land, Spitsbergen). We cover hydrometeorological measurements, fluctuations of physicochemical parameters (pH, specific electrolytic conductivity (SEC)), and the presence of selected organic compounds (dissolved organic carbon (DOC), formaldehyde (HCHO), ∑phenols). The obtained levels of DOC (0.061–0.569mgCL−1) and HCHO (<LOD-0.140mgL−1) in water samples of these two high Arctic creeks confirm the role of the melting permafrost as a rich source of terrestrial organic carbon and organic pollutants, as well as the impact of rainfall on surface water chemistry. It was found that fluctuations of physicochemical indices (pH, SEC, DOC) were related to changes in mean daily discharge of Reindeer Creek (0.012–0.034m3s−1) and Tyvjobekken Creek (0.011–0.015m3s−1) (r>0.40). The Tyvjobekken Creek catchment, in contrast to Reindeer Creek catchment, turned out to be resistant to rapid changes in meteorological conditions (r<0.10) and surface runoff. The processes of permafrost thawing, calcium carbonate dissolution, and biogeochemical “breathing” of soils proved to be crucial for the development of water chemistry. In conclusion, the surface water chemistry of the Reindeer Creek was found to result from the mutual influence of hydrometeorological indices and the biogeochemical environment of the catchment.

Impact of integrated application of biochar and nitrogen fertilizers on maize growth and nitrogen recovery in alkaline calcareous soil

ABSTRACTBiochar application has been considered as a rich source of carbon which helps to improve the physico-chemical properties and fertility of the soil. In Pakistan, excessive use of nitrogen fertilizer is considered a serious problem, so it is of vital importance to examine the effect of biochar on soil with varying doses of nitrogen fertilizer. We hypothesized that addition of biochar to an alkaline calcareous soil could improve not only soil quality and crop yield but also nitrogen use efficiency (NUE), reducing the loss of nitrogen (N) in the form of denitrification, ammonia volatilization, and nitrate leaching. A pot experiment was conducted under 2-factorial completely randomized design having three replications to evaluate the NUE in biochar amended calcareous soil. Biochar was applied at the rate of 0%, 1% and 2% (w/w) in pots filled with 17 kg of soil using various levels of N (0%, 50% and 100% of recommended dose) on maize (Zea mays L.). Several soil quality indicators, uptake, and yield of maize were monitored. Biochar application significantly decreased soil pH, increased water-holding capacity, total organic carbon, maize yield, stomatal conductance, and nitrogen uptake in plant. The results of the study indicated that addition of biochar could not only decrease the use of inorganic fertilizers by improving its quality and yield as in our case biochar at the rate of 1% and N at the rate of 50% provided optimum output minimizing the economic cost eventually.

Methanogenic degradation of toilet-paper cellulose upon sewage treatment in an anaerobic membrane bioreactor at room temperature

Toilet-paper cellulose with rich but refractory carbon sources, are the main insoluble COD fractions in sewage. An anaerobic membrane bioreactor (AnMBR) was configured for sewage treatment at room temperature and its performance on methanogenic degradation of toilet paper was highlighted. The results showed, high organic removal (95%), high methane conversion (90%) and low sludge yield (0.08gVSS/gCOD) were achieved in the AnMBR. Toilet-paper cellulose was fully biodegraded without accumulation in the mixed liquor and membrane cake layer. Bioconversion efficiency of toilet paper approached 100% under a high organic loading rate (OLR) of 2.02gCOD/L/d and it could provide around 26% of total methane generation at most of OLRs. Long sludge retention time and co-digestion of insoluble/soluble COD fractions achieving mutualism of functional microorganisms, contributed to biodegradation of toilet-paper cellulose. Therefore the AnMBR successfully implemented simultaneously methanogenic bioconversion of toilet-paper cellulose and soluble COD in sewage at room temperature.

Microbial community structure shifts are associated with temperature, dispersants and nutrients in crude oil-contaminated seawaters

This study tracked structure shifts of bacterial compositions before, during and after invading by crude oil to determine the microbial response and explore how temperature, dispersants and nutrients affect the composition of microbial communities or their activities of biodegradation in artificial marine environment. During petroleum hydrocarbons exposed, the composition and functional dynamics of marine microbial communities were altered, favoring bacteria that could utilize this rich carbon source such as the Proteobacteria, Firmicutes, Actinobacteria and Bacteroidetes phyla. Low temperature as a dominant factor decreased bacterial richness and catabolic diversity due to abated enzymes activities in correlation with the process of biodegradation. Dispersants exerted no negative consequences on microbial composition, however, bacterial composition by the Chloroflexi, TM6, OP8, Cyanobacteria and Gemmatimonadetes phyla increased. It seemed that more frequent fertilizer application could be equally safe to bacteria and increased significantly the abundance of bacterial strains but Actinobacteria phyla decreased.

Improving magnetic properties of MgB2 bulk superconductors by synthetic engine oil treatment

The present study focuses on the effects of standby time of the MgB2 samples immersed in synthetic engine oil on the critical current density ( Jc(H)), magnetic field dependence of the pinning force density fp(b) and Tc performances of MgB2 bulk superconductors. Synthetic engine oil was used as a product which is cheap and a rich carbon source. Manufactured MgB2 pellet samples were immersed at different standby time of 30min, 120min, 300min and 1440min in synthetic engine oil after the first heating process. Finally, MgB2 samples immersed in synthetic engine oil were sintered at 1000°C and kept for 15min in Ar atmosphere. The critical current density of all of MgB2 samples immersed at different standby time in engine oil in whole field range was better than that of the pure MgB2 sample because of the number of the pinning centers. The MgB2 sample immersed at 300min standby time in synthetic engine oil has the best performance compared to other samples. The Jc value for the pure sample is 2.0×103A/cm2, whereas for the MgB2 sample immersed at 300min standby time in engine oil the Jc is enhanced to 4.8×103A/cm2 at 5K and 3T. The superconducting transition temperature (Tc) did not change with the increasing standby time of the samples in synthetic engine oil at all. The best diamagnetic property was obtained from the sample which kept in synthetic engine oil for 300min. Synthetic engine oil treatment results in remarkable improvement of the critical current density and pinning force performances of MgB2 superconductors. It was found that all MgB2 samples have a different pinning property at different measuring temperatures. Using synthetic engine oil as a product which is cheap and a rich carbon source in MgB2 bulk superconductors makes MgB2 samples immersed in synthetic engine oil a good candidate for industrial applications.

Marine Oil Biodegradation

Crude oil has been part of the marine environment for millions of years, and microbes that use its rich source of energy and carbon are found in seawater, sediments, and shorelines from the tropics to the polar regions. Catastrophic oil spills stimulate these organisms to "bloom" in a reproducible fashion, and although oil does not provide bioavailable nitrogen, phosphorus or iron, there are enough of these nutrients in the sea that when dispersed oil droplets dilute to low concentrations these low levels are adequate for microbial growth. Most of the hydrocarbons in dispersed oil are degraded in aerobic marine waters with a half-life of days to months. In contrast, oil that reaches shorelines is likely to be too concentrated, have lower levels of nutrients, and have a far longer residence time in the environment. Oil that becomes entrained in anaerobic sediments is also likely to have a long residence time, although it too will eventually be biodegraded. Thus, data that encompass everything from the ecosystem to the molecular level are needed for understanding the complicated process of petroleum biodegradation in marine environments.

Learning from microbial strategies for polysaccharide degradation.

Complex carbohydrates are ubiquitous in all kingdoms of life. As major components of the plant cell wall they constitute both a rich renewable carbon source for biotechnological transformation into fuels, chemicals and materials, and also form an important energy source as part of a healthy human diet. In both contexts, there has been significant, sustained interest in understanding how microbes transform these substrates. Classical perspectives of microbial polysaccharide degradation are currently being augmented by recent advances in the discovery of lytic polysaccharide monooxygenases (LPMOs) and polysaccharide utilization loci (PULs). Fundamental discoveries in carbohydrate enzymology are both advancing biological understanding, as well as informing applications in industrial biomass conversion and modulation of the human gut microbiota to mediate health benefits.

Aerobic and Anaerobic Transformations in Estrogens and Nutrients in Swine Manure: Environmental Consequences

Pig manure is an excellent fertilizer and rich source of organic carbon and nitrogen compounds such organic nitrogen (O-N) (95% of total nitrogen) that is plant-unavailable-nitrogen (PUN) and mineralized nitrogen (about 1% of total nitrogen) such as ammonium (NH4+) and nitrate (NO3) that are plant-available-nitrogen (PAN). In addition, manure also contains two forms of estrogens: (i) poorly estrogenic thus essentially nontoxic conjugated estrogens (cEs) such as estrone (cE1), estradiol (cE2) and estriol (cE3); and (ii) highly estrogenic and toxic free estrogens (fEs) such as fE2, fE1 and fE3. This study showed that aerobic processing reduced concentrations of total carbon (TC), O-N, PAN and NH4+/NH3 ratio, transiently hydrolyzed cEs (cE2 &gt; cE1 &gt; cE3) into corresponding fEs, transiently increased estrogenic activity and potential toxicity, and rapidly degraded fEs (fE2, fE1 &gt; fE3), thus reducing the estrogenic activity in manure. Unlike aerobic processing, anaerobic processing stabilized and increased PAN and NH4+/NH3 ratio, thus increasing the manure’s fertilizer value. However, anaerobic processing, relative to aerobic processing, poorly hydrolyzed cEs (reducing transient toxicity and increasing reserve toxicity potential) and poorly degraded fEs (increasing toxicity) in manure. Thus, aerobic and anaerobic environments have distinct effects on manures’ PAN and estrogenic activity, presenting an interesting dilemma: anaerobic incubation that increases manures’ PAN does not effectively degrade estrogens, while aerobic incubation that effectively degrades estrogens (after transiently increasing their estrogenic activity) also decreases PAN, thus making manure less profitable. New techniques are need to fully use manure as organic fertilizer.

Can macroalgae contribute to blue carbon? An Australian perspective

AbstractMacroalgal communities in Australia and around the world store vast quantities of carbon in their living biomass, but their prevalence of growing on hard substrata means that they have limited capacity to act as long‐term carbon sinks. Unlike other coastal blue carbon habitats such as seagrasses, saltmarshes and mangroves, they do not develop their own organic‐rich sediments, but may instead act as a rich carbon source and make significant contributions in the form of detritus to sedimentary habitats by acting as a “carbon donor” to “receiver sites” where organic material accumulates. The potential for storage of this donated carbon however, is dependent on the decay rate during transport and the burial efficiency at receiver sites. To better understand the potential contribution of macroalgal communities to coastal blue carbon budgets, a comprehensive literature search was conducted using key words, including carbon sequestration, macroalgal distribution, abundance and productivity to provide an estimation of the total amount of carbon stored in temperate Australian macroalgae. Our most conservative calculations estimate 109.9 Tg C is stored in living macroalgal biomass of temperate Australia, using a coastal area covering 249,697 km2. Estimates derived for tropical and subtropical regions contributed an additional 23.2 Tg C. By extending the search to include global studies we provide a broader context and rationale for the study, contributing to the global aspects of the review. In addition, we discuss the potential role of calcium carbonate‐containing macroalgae, consider the dynamic nature of macroalgal populations in the context of climate change, and identify the knowledge gaps that once addressed will enable robust quantification of macroalgae in marine biogeochemical cycling of carbon. We conclude that macroalgal communities have the potential to make ecologically meaningful contributions toward global blue carbon sequestration, as donors, but given that the fate of detached macroalgal biomass remains unclear, further research is needed to quantify this contribution.

Production and Statistical Optimization of Oxytetracycline from Streptomyces rimosus NCIM 2213 using a New Cellulosic Substrate, Prosopis juliflora

Prosopis juliflora is a drought-resistant evergreen spiny tree that grows in semi-arid and arid tracts of tropical and sub-tropical regions of the world. Dry pods of P. juliflora are a rich source of carbon (40% total sugar) and nitrogen (15% of total nitrogen) and so can be considered as a good substrate for the microbial growth. The present study was mainly focused on the utilization of these pods for the production and statistical optimization of oxytetracycline (OTC) from Streptomyces rimosus NCIM 2213 under SSF. The spectral characterization and chemical color reactions of purified OTC by UV, FTIR, 1H NMR, 13C NMR, and HPLC revealed that the structure was homologous to a standard sample. A central composite design with 26 trails yielded the following critical values of supplements to be added to the dry pods: maltose (0.125 g/gds), Inoculum size (0.617 mL/gds), CaCO3 (0.0026 g/gds), and moisture content (74.87%) with the maximum OTC yield 5.02 mg/gds.

Evaluation of production of xanthan gum utilizing the corn cob liquor as a carbon source in different strains of Xanthomonas campestres

Background The xanthan gum production has been growing significantly. It is estimated an annual increase by about 5 to 10%. The production needs a carbon source in fermentation media and are commonly employed as glucose or sucrose, which accounts for about 50% of the cost of production. Therefore the use of agro-industrial residues, such as corn cob for the production of xanthan gum becomes suggestive, as such residues are abundant. Waste when processed becomes a rich source of carbon, nutrients and salts. Thus this study aims to use hemicellulose fractions, derived from agro-industrial residues.

The metabolic pathways and environmental controls of hydrocarbon biodegradation in marine ecosystems.

The metabolic pathways and environmental controls of hydrocarbon biodegradation in marine ecosystems.

The microbial nitrogen cycling potential is impacted by polyaromatic hydrocarbon pollution of marine sediments.

During hydrocarbon exposure, the composition and functional dynamics of marine microbial communities are altered, favoring bacteria that can utilize this rich carbon source. Initial exposure of high levels of hydrocarbons in aerobic surface sediments can enrich growth of heterotrophic microorganisms having hydrocarbon degradation capacity. As a result, there can be a localized reduction in oxygen potential within the surface layer of marine sediments causing anaerobic zones. We hypothesized that increasing exposure to elevated hydrocarbon concentrations would positively correlate with an increase in denitrification processes and the net accumulation of dinitrogen. This hypothesis was tested by comparing the relative abundance of genes associated with nitrogen metabolism and nitrogen cycling identified in 6 metagenomes from sediments contaminated by polyaromatic hydrocarbons from the Deepwater Horizon (DWH) oil spill in the Gulf of Mexico, and 3 metagenomes from sediments associated with natural oil seeps in the Santa Barbara Channel. An additional 8 metagenomes from uncontaminated sediments from the Gulf of Mexico were analyzed for comparison. We predicted relative changes in metabolite turnover as a function of the differential microbial gene abundances, which showed predicted accumulation of metabolites associated with denitrification processes, including anammox, in the contaminated samples compared to uncontaminated sediments, with the magnitude of this change being positively correlated to the hydrocarbon concentration and exposure duration. These data highlight the potential impact of hydrocarbon inputs on N cycling processes in marine sediments and provide information relevant for system scale models of nitrogen metabolism in affected ecosystems.

Integrated Sugarcane Trash Management: A Novel Technology for Sustaining Soil Health and Sugarcane Yield

With the raising concern on soil conservation and health in the context of depleting traditional organic manures, efforts are required to harness the potentiality of crop biomass wastes effectively. Sugarcane is one such crop that produces 7-12 t ha-1 of trash, which is a rich source of organic carbon and plant nutrients. The burning of trash would lead to environment pollution besides depleting the soil biological properties and fertility. In this context, integrated sugarcane trash management (ISTM) that conserves and decomposes trash using microbial enriched (Trichoderma viridae) farm yard manure and urea (75 kg/ha) serve as a novel technology in sustaining soil health and sugarcane yield. The results revealed that intense heat generated due to trash burning has reduced the germination of sugarcane to an extent of 68 percent compared to 82 percent in ISTM. The ISTM has increased the organic carbon content, available nitrogen, phosphorus and potassium in soil to an extent of 11.2, 3.6, 8.5 and 11.2 percent respectively in three years. The increased average cane yield was 12.8 percent over trash burning. The economic analysis showed that the gross income increased to 18.2 percent with the benefit of 2.63 rupees per rupee invested over three years. Farmers surveyed indicated that the trash management technology increased soil moisture and number of earthworms, and reduced weed incidence. Farmers also expressed that buds germinated 15 days earlier in ISTM practice and that ISTM increased cane yield and did not hinder ratoon practices.

Extracellular DNA metabolism in Haloferax volcanii

Extracellular DNA is found in all environments and is a dynamic component of the microbial ecosystem. Microbial cells produce and interact with extracellular DNA through many endogenous mechanisms. Extracellular DNA is processed and internalized for use as genetic information and as a major source of macronutrients, and plays several key roles within prokaryotic biofilms. Hypersaline sites contain some of the highest extracellular DNA concentrations measured in nature–a potential rich source of carbon, nitrogen, and phosphorus for halophilic microorganisms. We conducted DNA growth studies for the halophilic archaeon Haloferax volcanii DS2 and show that this model Halobacteriales strain is capable of using exogenous double-stranded DNA as a nutrient. Further experiments with varying medium composition, DNA concentration, and DNA types revealed that DNA is utilized primarily as a phosphorus source, that growth on DNA is concentration-dependent, and that DNA isolated from different sources is metabolized selectively, with a bias against highly divergent methylated DNA. Additionally, fluorescence microscopy showed that labeled DNA co-localized with H. volcanii cells. The gene Hvo_1477 was also identified using a comparative genomic approach as a factor likely to be involved in DNA processing at the cell surface, and deletion of Hvo_1477 created a strain deficient in the ability to grow on extracellular DNA. Widespread distribution of Hvo_1477 homologs in archaea suggests metabolism of extracellular DNA may be of broad ecological and physiological relevance in this domain of life.