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Trans-aconitic acid (TAA) is naturally present in sweet sorghum juice and syrup, and it has been promoted as a potential biocontrol agent for nematodes. Therefore, we developed a process for the extraction of aconitic acid from sweet sorghum syrup. The process economics were evaluated, and the extract was tested for its capability to suppress the motility of the nematodes Caenorhabditis elegans and Meloidogyne incognita. Aconitic acid could be efficiently extracted from sweet sorghum syrup using acetone:butanol:ethanol mixtures, and it could be recovered from this solvent with a sodium carbonate solution, with an overall extraction and recovery efficiency of 86%. The estimated production cost was USD 16.64/kg of extract and this was highly dependent on the solvent cost, as the solvent was not recycled but was resold for recovery at a fraction of the cost. The extract was effective in reducing the motility of the parasitic M. incognita and causing over 78% mortality of the nematode when 2 mg/mL of TAA extract was added. However, this positive result could not conclusively be linked solely to TAA. An unidentified component (or components) in the acetone:butanol:ethanol sweet sorghum extract appears to be an effective nematode inhibitor, and it may merit further investigation. The impact of aconitic acid on C. elegans appeared to be entirely controlled by pH. [ABSTRACT FROM AUTHOR]

Biochar has gained significant interest in the literature, mainly for its ability to improve soil quality and sequester carbon. This work investigated if results from proximate analysis could be used to assess the quality of the biochar. Normally, ultimate analysis results are used for this purpose. A large set of data was collected from literature and various mathematical correlation were investigated to determine if quality parameters such as carbon mass fraction and H/C and O/C mol ratios could be estimated from proximate analysis results. It was determined that the mass fraction of carbon in the biochar could be correlated to the mass fractions of volatile matter (VM), fixed carbon (FC), and ash (ASH) by the relationship C = 0.474 × VM+0.963 × FC+0.067 × ASH. The mass fraction of oxygen in biochar could also be correlated to VM, FC, and ASH, while hydrogen was best correlated to a relationship with VM, FC, and VM/FC. Atomic ratios, such as H/C and O/C, used for biochar classification by international standards and carbon sequestration potential, were best correlated to VM/FC by the expressions H/C = 0.379 × VM/FC+0.251 and O/C = 0.188 × VM/FC+0.035. The developed correlations were proven to accurately classify biochar when the biochar had been made at ≥400 °C. [ABSTRACT FROM AUTHOR]

Characterization of biochars usually includes surface area and pore volume determinations by nitrogen adsorption. In this study, we confirmed that there is a substantial pore volume in biochars created via slow pyrolysis from low- and high-ash almond shells that cannot be characterized in this fashion due to the narrow pore sizes. Hydrogen and carbon dioxide were used, in addition to nitrogen, to characterize these narrow micropores. All isotherms, when appropriately normalized, fell on the same characteristic curve which aided in the characterization and understanding of the pore structure. Based on the characteristic adsorption isotherm, the average pore size diameter was estimated to be 0.4–0.8 nm. When washed, the biochars’ pore volume increased but the narrow micropore structure remained. While the biochars were alkaline, the pH of the wash solution had no or little impact on the adsorption of CO 2 . Overall, the results suggest that N 2 isotherms should be complemented with CO 2 isotherms for proper characterization of biochars. Alignment of such normalized isotherms to characteristic curves can assist in generating a more complete understanding of the pore structure over the entire region of pore diameters. [ABSTRACT FROM AUTHOR]

Biochars have been considered for adsorption of contaminants in soil and water, as well as conditioning and improving soil quality. Pore surface area is an important property of biochar. Biochars were created from shells of two almond varieties with different ash content. The pyrolysis was performed at 650 and 800 °C for 40-240 min. Significant surface areas developed at the higher temperature and at pyrolysis times of 120 min and longer. Washing the materials in synthetic rainwater removed ash and exposed additional surface area, particularly in small-diameter pores. When results from low-ash almond shell biochars were compared with high-ash almond shell biochars, it was found that the pore distribution was more uniform for the high-ash starting material and almost independent of pyrolysis time or washing. The result from the washing study is important as it suggested that adsorptive properties may change once biochars are exposed to rainwater. [ABSTRACT FROM AUTHOR]

Highlights: [•] We showed that biochar from agricultural residues can remove fermentation inhibitors. [•] We showed a reduced fermentation lag phase when inhibitors were removed. [•] We demonstrated that the biochar can remain in the broth during fermentation. [•] Neither enzyme nor yeast appeared negatively affected by biochar. [ABSTRACT FROM AUTHOR]

Lignocellulosic feedstocks are often prepared for ethanol fermentation by treatment with a dilute mineral acid catalyst that hydrolyzes the hemicellulose and possibly cellulose into soluble carbohydrates. The acid-catalyzed reaction scheme is sequential, whereby the released monosaccharides are further degraded to furans and other chemicals that are inhibitory to the subsequent fermentation step. This work tests the use of agricultural residues (e.g., plant waste) as starting materials for making activated biochars to adsorb these degradation products. Results show that both furfural and hydroxymethylfurfural (HMF) are adsorbed by phosphoric acid-activated and steam-activated biochars prepared from residues collected from cotton and linen production. Best results were obtained with steam-activated biochars. The activated biochars adsorbed about 14% (by weight) of the furfurals at an equilibrium concentration of 0.5 g/L, and by adding 2.5% of char to a sugar solution, with either furfural or HMF (at 1 g/L), 99% of the furans were removed. [ABSTRACT FROM AUTHOR]

Abstract: Contaminant desorption constrains the long-term effectiveness of remediation technologies, and is strongly influenced by dynamic non-equilibrium states of environmental and biological media. Information is currently lacking in the influence of biochar and activated carbon amendments on desorption of heavy metal contaminants from soil components. In this study, copper sorption–desorption isotherms were obtained for clay-rich, alkaline San Joaquin soil with significant heavy metal sorption capacity, and eroded, acidic Norfolk sandy loam soil having low capacity to retain copper. Acidic pecan shell-derived activated carbon and basic broiler litter biochar were employed in desorption experiments designed to address both leaching by rainfall and toxicity characteristics. For desorption in synthetic rain water, broiler litter biochar amendment diminished sorption–desorption hysteresis. In acetate buffer (pH 4.9), significant copper leaching was observed, unless acidic activated carbon (pHpzc =3.07) was present. Trends observed in soluble phosphorus and zinc concentrations for sorption and desorption equilibria suggested acid dissolution of particulate phases that can result in a concurrent release of copper and other sorbed elements. In contrast, sulfur and potassium became depleted as a result of supernatant replacements only when amended carbon (broiler litter biochar) or soil (San Joaquin) contained appreciable amounts. A positive correlation was observed between the equilibrium aluminum concentration and initial copper concentration in soils amended with acidic activated carbon but not basic biochar, suggesting the importance of cation exchange mechanism, while dissolution of aluminum oxides cannot be ruled out. [Copyright &y& Elsevier]

Abstract: The amendment of carbonaceous materials such as biochars and activated carbons is a promising in situ remediation strategy for both organic and inorganic contaminants in soils and sediments. Mechanistic understandings in sorption of heavy metals on amended soil are necessary for appropriate selection and application of carbonaceous materials for heavy metal sequestration in specific soil types. In this study, copper sorption isotherms were obtained for soils having distinct characteristics: clay-rich, alkaline San Joaquin soil with significant heavy metal sorption capacity, and eroded, acidic Norfolk sandy loam soil having low capacity to retain copper. The amendment of acidic pecan shell-derived activated carbon and basic broiler litter biochar lead to a greater enhancement of copper sorption in Norfolk soil than in San Joaquin soil. In Norfolk soil, the amendment of acidic activated carbon enhanced copper sorption primarily via cation exchange mechanism, i.e., release of proton, calcium, and aluminum, while acid dissolution of aluminum cannot be ruled out. For San Joaquin soil, enhanced copper retention by biochar amendment likely resulted from the following additional mechanisms: electrostatic interactions between copper and negatively charged soil and biochar surfaces, sorption on mineral (ash) components, complexation of copper by surface functional groups and delocalized π electrons of carbonaceous materials, and precipitation. Influence of biochar on the release of additional elements (e.g., Al, Ca) must be carefully considered when used as a soil amendment to sequester heavy metals. [Copyright &y& Elsevier]

Increased emphasis on reduction of mercury emissions from coal fired electric power plants has resulted in environmental regulations that may in the future require application of activated carbons as mercury sorbents for mercury removal. At the same time, the quantity of poultry manure generated each year is large and technologies that take advantage of the material should be explored. The purpose of the work was to obtain preliminary data to investigate if activated chars made from different poultry manures could adsorb mercury from simulated flue gas. In laboratory experiments, activated chars made from chicken cake and litter removed mercury from the gas as well as a commercial alternative. It was also found that acid-washing these chars after activation may improve pore structure but does not influence the mercury removal efficiency. Activated chars were also made from turkey cake and litter. These raw materials produced activated chars with similar pore structure as those made from chicken manure, but they did not adsorb mercury as well. Acid-washing the turkey manure-based chars improved their performance, but this step would add to the cost of production. Preliminary evaluations suggest that unwashed activated chars may cost as little as $0.95/kg to produce. [Copyright &y& Elsevier]

Abstract: Agricultural by-products represent a considerable quantity of harvested commodity crops. The use of by-products as precursors for the production of widely used adsorbents, such as activated carbons, may impart a value-added component of the overall biomass harvested. Our objective in this paper is to show that flax shive and cotton gin waste can serve as a precursor for activated carbon that can be used for adsorption of trichloroethylene (TCE) from both the liquid and gas phases. Testing was conducted on carbon activated with phosphoric acid or steam. The results show that activated carbon made from flax shive performed better than select commercial activated carbons, especially at higher TCE concentrations. The activation method employed had little effect on TCE adsorption in gas or vapor phase studies but liquid phase studies suggested that steam activation is slightly better than phosphoric acid activation. As expected, the capacity for the activated carbons depended on the fluid phase equilibrium concentration. At a fluid concentration of 2mg of TCE/L of fluid, the capacity of the steam activated carbon made from flax shive was similar at 64 and 80mg TCE/g of carbon for the vapor and liquid phases, respectively. Preliminary cost estimates suggest that the production costs of such carbons are $1.50 to $8.90 per kg, depending on activation method and precursor material; steam activation was significantly less expensive than phosphoric acid activation. [Copyright &y& Elsevier]

Abstract: Agricultural by-products represent a considerable quantity of harvested commodity crops. The use of by-products as precursors for the production of widely used adsorbents, such as activated carbons, may impart a value-added component of the overall biomass harvested. Our objective in this paper is to show how the partial oxidation of phosphoric acid-impregnated pecan shells resulted in activated carbons with different affinities for a typical metal ion, copper(II), in aqueous sorption studies. The oxygen level was varied during activation by altering the sweep gas (air) flow rate in the furnace. Surface area and micropore volume of the produced carbon did not vary significantly with degree of oxidation, while the surface charge and the adsorption capacity were strongly dependent on the oxidative conditions. Surface area functional groups of Cics, and phosphorus were confirmed by infrared spectroscopy. The results show that the yield of activated carbon product was higher in the more oxygen-deprived atmosphere but that the product had a lower affinity for adsorbing copper from an aqueous solution. The carbon with the highest adsorptive capacity was produced by activation in approximately 14% oxygen atmosphere, yielding adsorption values of 0.97 and 1.3mmol of copper(II) per gram of carbon when the carbon had been in contact with a copper(II) solution with initial concentration of 10 and 20mM of copper, respectively. [Copyright &y& Elsevier]

Demand for bioethanol and other biochemicals produced from agricultural crops has increased. Sweet sorghum has been identified as a promising bioenergy crop as it can produce starch, sugar, and fibrous biomass. During processing, starch accumulates in the juice sediments and clarification mud. And, while currently not recovered, it can be made accessible for fermentation by enzymatic hydrolysis. The enzymatic hydrolysis of starch in sweet sorghum processing streams was investigated, followed by fermentation of the resulting glucose to ethanol. The juice sediment contained sufficient starch to increase fermentable sugars by 127%, allowing a final ethanol titer of 11.1 vol%. The economics for fermentation of only dissolved sugars (Scenario 1) versus dissolved sugars and hydrolyzed starch (Scenario 2) were compared using a technoeconomic model. Fixed capital cost was found to be similar for both scenarios. For a set harvest period, Scenario 2 could produce 20% more ethanol; however, if the distillation by-product was dried and marketed as animal feed, Scenario 1 was more cost effective. A plant producing 5.6–5.7 Mkg of fuel ethanol per year had a minimum selling price of $0.67/kg of ethanol with concurrent production of animal feed and zero cost sweet sorghum processing. Even with these optimistic assumptions, the estimated production cost was higher than the current wholesale price of fuel ethanol. • Starch in sweet sorghum processing byproducts can be converted to fermentable sugars. • Sweet sorghum juice sediments contained the highest level of starch. • Fermentable sugar levels increased 127% in fermentation broth after starch conversion. • Bioethanol was efficiently produced from existing and starch-derived sugars. • While starch could be efficiently converted to sugars, it was not economical. [ABSTRACT FROM AUTHOR]

Abstract: Experimental data are often in need of smoothing without a pre-determined trend line equation. This manuscript demonstrates how spreadsheet software can be programmed to smooth experimental data via cubic splines. Once the trend lines (splines) have been constructed, it is also simple to interpolate values and calculate derivatives and integrals. The formulas to carry out the calculation are listed and explained in the manuscript. [Copyright &y& Elsevier]

A liquid- liquid centrifugal separator has been modified for possible application as a downhole method for separating crude oil from produced water Centrifugal separators of various sizes (from 2- to 25-cm rotor diameter) have been built and operated over the past decades at various U.S. Department of Energy facilities. These units have several characteristics that make them attractive for downhole applications, including excellent phase separation, reliability in remote applications with > 20,000 h of operation prior to maintenance, and the ability to handle high volumetric throughput with a very low residence time. These separators consist of a abating cylinder in which the two phases are separated and a stationary housing that collects the separated streams. This paper discusses some of the aspects of the alterations required for downhole operation. Specifically, we discuss modifications of the exterior housing allowing for greater flow through the system. The system presented here improves the performance of a standard separator by 140%. [ABSTRACT FROM AUTHOR]

A liquid–liquid centrifuge has been tested for possible application as a downhole method for separating crude oil from produced water. Centrifugal separators of various sizes (from 2- to 25-cm rotor diameter) have been built and operated over the past three decades at various US Department of Energy facilities. These units have several characteristics that make them attractive for downhole applications, including excellent phase separation, reliability in remote applications with>20,000 h of operation prior to maintenance, and the ability to handle high volumetric throughput with a very low residence time. In these studies, water-to-oil feed ratios of 10:1 to 1:19 were tested with a light Gulf of Mexico crude oil, and the separator operated efficiently for the full range of feed ratios. Air was added to the oil stream in one test to model the effect of gas in the oil. Air additions up to 20% of the feed flow rate (the maximum tested) did not have any impact on the performance of the separator. The separator also effectively processed a very viscous North Sea heavy crude oil. The heavy crude was used to determine the effect of higher temperatures on the performance of the separator. Increasing the temperature of the oil and water feed stream improved overall performance and decreased the concentration of oil in the water discharge stream. [ABSTRACT FROM AUTHOR]

Gas chromatography was used to measure the ozone concentration in oxygen produced by an ozone generator. In this indirect method, the ozone reacts with the coating of the capillary column and produces carbon dioxide, which is then detected. The primary methods of calibration for this technique were based on a wet-chemistry process and absorption of ultraviolet light. This finding also is important if the primary reason for using gas chromatography is detection of carbon dioxide, as artificially high readings of carbon dioxide would be measured in the presence of ozone. The method was tested for ozone concentrations of 3-70 mg/L but the method should also be applicable to higher concentrations. [ABSTRACT FROM AUTHOR]

Several researchers have demonstrated the transformation of polychlorinated biphenyls (PCBs) by both aerobic and anaerobic bacteria. This transformation, or conversion, is characteristic and often dependent on PCB congener structure and, in addition, dictates the products or extent of degradation. Because transformation is linked to microbial activities, bioremediation has been hailed as a possible solution for PCB-contaminated soils and sediments, and several demonstration activities have verified laboratory results. This article presents results from mathematical modeling of anaerobic microbial PCB transformation. Because transformation can be influenced by both starting composition of the PCBs and microbial activity, this article systematically evaluates several of the most common transformation patterns. The predicted data are also compared with experimental results. For example, the correlation between laboratory-observed and predicted products was, in some cases, as good as 0.96 (perfect correlation = 1.0). In addition to predicting extent of transformation, the water solubility and the possible human effects of the PCBs are discussed through the use of documented dioxin-like toxicity and accumulation in humans before and alter transformation. [ABSTRACT FROM AUTHOR]

Cottonseed is a natural product of cotton (Gossypium spp.) crops. This work evaluated the oxidative stability of cottonseed butters through accelerated autoxidation by storage at 60 °C for 25 days. Three oxidative stability parameter values (peroxide value, p-anisidine value, and total oxidation value) were monitored over the storage time. These chemical measurements revealed that the storage stability of the butter products was dominated by primary oxidation of lipid (oil) components, while the secondary oxidation levels were relatively unchanged over the storage time. An analysis of the tocopherols (natural oxidants in cottonseed) suggested not only the protection function of the molecules against oxidation of the cottonseed butter during storage, but also the dynamic mechanism against the primary oxidation of lipid components. Attenuated total reflectance–Fourier-transform infrared spectroscopy (ATR–FTIR) data confirmed no changes in the major C functional groups of cottonseed butters over the storage time. On the other hand, characteristic minor peaks of conjugated dienes and trienes related to lipid oxidation were impacted by the accelerated storage. As each day of accelerated oxidation at 60 °C is equivalent to 16 days of storage at 20 °C, observations in this work should have reflected the oxidative stability behaviors of the cottonseed butters after about 13 months of shelf storage under ambient storage conditions. Thus, these data that were collected under the accelerated oxidation testing would be useful not only to create a better understanding of the autooxidation mechanism of lipid molecules in cottonseed butters, but also in developing or recommending appropriate storage conditions for cottonseed end products to prevent them from quality degradation. [ABSTRACT FROM AUTHOR]

• Sugar loss was reduced when more concentrated syrups were stored. • Vegetable oil on top of the syrup reduced sugar loss in 30 and 40°Brix syrups. • Storage of 50°Brix syrup for 10 weeks resulted in an 11–18 % loss of sugars. • Some stored syrups were good for bioethanol with yields of 83–91 % of theoretical. Sweet sorghum represents a readily available renewable carbohydrate feedstock for biofuel production. Generally, the sweet sorghum growing season and window for processing is short and it is often desirable to store a sugar-rich material for future processing. Therefore, we investigated the possibility of storing three different sweet sorghum sugar syrups under a layer of soybean oil; then we investigated subsequent yeast bioethanol fermentation. A layer of oil on the surface of the syrup reduced sugar loss in 30 and 40°Bx syrups, but the loss was still 21–36 %. Storage of 50°Bx syrup resulted in an 11–18 % loss of sugars with or without a surface layer of oil. Elevated levels of lactic and acetic acids, caused by bacterial contamination, almost completely inhibited yeast fermentation; however, when ethanol-producing microorganisms were part of the contamination, stored syrups produced a bioethanol at a yield of 83–91 %, compared to theoretical. [ABSTRACT FROM AUTHOR]

Water washing of cottonseed meal is more cost-efficient and environmentally friendly than protein isolation by means of alkaline extraction and acidic precipitation. Thus, water-washed cottonseed meal (WCSM) is more promising as biobased wood adhesives. In this work, we examined the effects of the particle size on the morphology and adhesive performance of WCSM. Pilot-scale produced and dried WCSM was treated by three grinding methods: (1) ground by a hammer mill and passed through a 0.5-mm screen, (2) further ground by a cyclone mill and passed through a 0.5-mm screen, or (3) further ground by a ball mill and passed through a 0.18-mm screen. Micro-morphological examination revealed two types of particles. The filament-like particles were mainly fibrous materials from residual linters. Chunk-like particles were more like aggregates or accumulations of small particles, with proteins as the major component. Further grinding of the 0.5-mm Hammer product with the Cyclone and Ball mill led to more fine (smaller) particles in the WCSM products. The impact of further grinding on the dry and soaked adhesive strengths was minimal. However, the decrease of the hot and wet strengths of WCSM products by the additional grinding was significant (p ≤ 0.05). Data presented in this work is useful in developing the industrial standards of WCSM products used in wood bonding. [ABSTRACT FROM AUTHOR]

Diacylglycerol acyltransferases (DGAT) catalyze the final and rate-limiting step of triacylglycerol (TAG) biosynthesis in eukaryotic organisms. DGAT genes have been identified in numerous organisms. Multiple isoforms of DGAT are present in eukaryotes. We previously cloned DGAT1 and DGAT2 genes of tung tree (Vernicia fordii), whose novel seed TAGs are useful in a wide range of industrial applications. The objective of this study was to understand the developmental regulation of DGAT family gene expression in tung tree. To this end, we first cloned a tung tree gene encoding DGAT3, a putatively soluble form of DGAT that possesses 11 completely conserved amino acid residues shared among 27 DGAT3s from 19 plant species. Unlike DGAT1 and DGAT2 subfamilies, DGAT3 is absent from animals. We then used TaqMan and SYBR Green quantitative real-time PCR, along with northern and western blotting, to study the expression patterns of the three DGAT genes in tung tree tissues. Expression results demonstrate that 1) all three isoforms of DGAT genes are expressed in developing seeds, leaves and flowers; 2) DGAT2 is the major DGAT mRNA in tung seeds, whose expression profile is well-coordinated with the oil profile in developing tung seeds; and 3) DGAT3 is the major form of DGAT mRNA in tung leaves, flowers and immature seeds prior to active tung oil biosynthesis. These results suggest that DGAT2 is probably the major TAG biosynthetic isoform in tung seeds and that DGAT3 gene likely plays a significant role in TAG metabolism in other tissues. Therefore, DGAT2 should be a primary target for tung oil engineering in transgenic organisms. [ABSTRACT FROM AUTHOR]

Abstract: Oxygen-containing carboxyl, hydroxyl, and phenolic surface functional groups of soil organic and mineral components play central roles in binding metal ions, and biochar amendment can provide means of increasing these surface ligands in soil. In this study, positive matrix factorization (PMF) was first employed to fingerprint the principal components responsible for the stabilization of heavy metals (Cu, Ni, Cd, Pb) and the release of selected elements (Na, Ca, K, Mg, S, Al, P, Zn) and the pH change in biochar amended soils. The PMF analysis indicated that effective heavy metal stabilization occurred concurrently with the release of Na, Ca, S, K, and Mg originating from soil and biochar, resulting in as much as an order or magnitude greater equilibrium concentrations relative to the soil-only control. In weathered acidic soil, the heavy metal (especially Pb and Cu) stabilization ability of biochar directly correlated with the amount of oxygen functional groups revealed by the O/C ratio, pHpzc, total acidity, and by the 1H NMR analysis. Equilibrium speciation calculation showed minor influence of hydrolysis on the total soluble metal concentration, further suggesting the importance of binding by surface ligands of biochar that is likely to be promoted by biochar-induced pH increase. [Copyright &y& Elsevier]

Abstract: Contamination of soil interstitial waters by labile heavy metals such as Cu(II), Cd(II), and Ni(II) is of worldwide concern. Carbonaceous materials such as char and activated carbon have received considerable attention in recent years as soil amendment for both sequestering heavy metal contaminants and releasing essential nutrients like sulfur. Information is currently lacking in how aging impacts the integrity of biochars as soil amendment for both agricultural and environmental remediation purposes. Major contributors to biochar aging in soils are: sorption of environmental constituents, especially natural organic matter (NOM), and oxidation. To investigate the impact of NOM and organic fractions of chars, we employed broiler litter-derived chars and steam-activated carbons that underwent varying degrees of carbonization, in the presence and absence of NOM having known carboxyl contents. For aging by oxidation, we employed phosphoric acid activated carbons that underwent varying degrees of oxidation during activation. The results suggest that the organic fractions of biochars, and NOM having high carboxyl contents can mobilize Cu(II) retained by alkaline soil. Base treatment of broiler litter-derived char formed at low pyrolysis temperature (350°C) improved the immobilization of all heavy metals investigated, and the extent of immobilization was similar to, or slightly greater than pecan shell-derived phosphoric acid activated carbons. Portions of total sulfur were released in soluble form in soil amended with broiler litter-derived carbons, but not pecan shell-derived phosphoric acid activated carbons. [Copyright &y& Elsevier]

Abstract: A large number of solid-state NMR and ESR experiments were explored as potential tools to study chemical structure, mobility, and pore volume of activated carbon. We used a model system where pecan shells were activated with phosphoric acid, and carbonized at 450°C for 4h with varying amounts of air flow. Through the use of different NMR experiments (e.g., CP-MAS, SPE-MAS, and DD-MAS) several structural parameters were calculated such as mole fraction of bridgehead aromatic carbons, number of carbons per aromatic ring system, and number of phenolic carbons per aromatic ring system. The relaxation time measurements (T 1, T CH, and ) were indicative of the relative mobility of different structural units. ESR spectra showed the presence of π-type aromatic free radicals in the carbonized samples with a slight shift in g value with increasing oxidation. The combined NMR and ESR data give a consistent picture of the carbon structure and the carbonization process, which is not easily available otherwise. In addition, the 1H NMR data on adsorbed water are shown to be consistent with the trends in the amount of pore volumes for different samples of activated carbons. [Copyright &y& Elsevier]

The interest in biobased wood adhesives has steadily increased in recent years. Our previous studies have shown that water-washed cottonseed meal (WCSM) could be used as low-temperature and high-solid content biobased wood adhesives for non-structural bonding as European Standard Class D1 adhesives. In this work, we optimized WCSM-based adhesive formulations with high solid contents up to 49% for bonding of small wood items at low temperatures (40 °C). Chemical denaturing reagents guanidine hydrochloride (GdmCl) and sodium dodecyl sulfate (SDS) were added to improve the bonding capability and viscosity of WCSM. Reviewing industry preferences, four formulations with 20% and 30% of WCSM as well as 9.6% and 19.1% of SDS were used to glue "real world" pencil slat sandwiches for pencil making. All the pencils made from these sandwiches bonded at 40 °C and 1 MPa for 120 min passed the Industrial Temperature Cycle test. The results indicated that WCSM could be used as a low temperature wood adhesive, possibly for the domestic furniture and small utensils niche markets. The pencil sandwich bonding represents a specific application that could benefit from the non-toxic glue and also be an example of an interior application. [ABSTRACT FROM AUTHOR]

Graphical abstract Highlights • Water washed cottonseed meal (WCSM) is a good bio-based wood adhesive resource. • Adhesive strength and spreadability of WCSM improved with higher protein content. • WCSM with 50–70% protein recommended as cost-effective adhesive candidates per applications. • Information useful in quality standard setup for industrial production of WCSM. Abstract Water washed cottonseed meal (WCSM) is an excellent bio-adhesive resource because of its cost-effective extraction process and environmentally friendly performance. To evaluate the effects of protein content on the adhesive performance of cottonseed meal-based adhesives, we reconstituted cottonseed meal products with protein contents ranged from 34.9% to 94.8% by blending different amounts of WCSM, cottonseed protein isolate (CSPI), and residues after protein extraction (CSIR). Their physicochemical properties and three types of adhesive strengths (dry, wet, and soaked) were measured with press temperatures at 100, 150 and 170 °C. The morphological and rheological data showed that the low-protein-content adhesives with a high amount of residual cotton hull and fiber possessed poor spreadability and adhesive strength. Molecular and thermal analysis suggested that protein ratio had a stronger influence than press temperature to thermal property and adhesive strength. With these data, multiple linear regression models were established, providing analytical tools to predict the bonding strength affected by protein content and press temperature in cottonseed meal-based adhesives. On the other hand, the blends with 65–70% of protein content demonstrated the bonding performance and flowability comparable to highest protein product CSPI (94.8% protein) within the acceptable standard deviations. Thus, these observations and data could be helpful in set-up of industrial standard requirements and quality control for protein content in cost-effective adhesive-grade WCSM products. [ABSTRACT FROM AUTHOR]

• Both total and potential phenolic formulas increased with higher temperatures. • Top 10 identifiable compounds of the ethanol-extractable components reported. • Identities of selected 15 phenolic and nonphenolic bioactive compounds reported. • Roasting up to 140 °C increased extractable carbohydrates, lignins and tannins. • Less composition changes detected with 150 °C roasting due to devolatilization. Roasting is a technological process in some food applications of agricultural products. To investigate the composition changes of the extractable functional/bioactive components of cottonseed, in this work, glandless cottonseed kernels were roasted at 110, 120, 140 and 150 °C for 15 min, respectively. The UV/vis data of the 80 % ethanol extracts found that roasting increased the level of phenolic compounds. Electrospray ionization Fourier transform ion cyclotron resonance mass spectrometry of the extracts identified about 44 % to 55 % of total formulas as potential phenolic compounds. Roasting (up to 140 °C) mainly increased carbohydrate-, lignin-, and tannin-like compounds while lipid-like compounds decreased. The compositional changes at 150 °C were less than those at 140 °C, attributed to devolatilization at the higher temperature. The information of chemical profiling of cottonseed and the roasting impact would be greatly useful in enhanced utilization of cottonseed as nutrient and functional foods or food supplements. [ABSTRACT FROM AUTHOR]

Pecan shell-based biochar is utilized as a filtration medium, sequestrant for metallic ions, soil conditioner, and other applications. One process for creating the biochar involves the use of phosphoric acid at high temperature in a partial oxygen atmosphere to produce a highly porous carbonaceous material. In this work, we found129Xe NMR to be an excellent technique to study micropores in biochar. Thus, the129Xe chemical shift in biochar was found to vary linearly with the xenon pressure; from the data an estimate of about 8–9 Å could be proposed for the average pore diameter in pecan shell-based biochar. Through saturation recovery and 2-D NMR exchange experiments, information on the exchange between free versus bound xenon was obtained. Furthermore, correlations of129Xe NMR data with the carbonization process conditions were made. [ABSTRACT FROM PUBLISHER]

Background: Diacylglycerol acyltransferases (DGATs) catalyze the final and rate-limiting step of triacylglycerol (TAG) biosynthesis in eukaryotic organisms. Database search has identified at least 59 DGAT1 sequences from 48 organisms, but the expression of any DGAT1 as a full-length protein in E. coli had not been reported because DGAT1s are integral membrane proteins and difficult to express and purify. The objective of this study was to establish a procedure for expressing full-length DGAT1 in E. coli. Results: An expression plasmid containing the open reading frame for tung tree (Vernicia fordii) DGAT1 fused to maltose binding protein and poly-histidine affinity tags was constructed and expressed in E. coli BL21(DE3). Immunoblotting showed that the recombinant DGAT1 (rDGAT1) was expressed, but mostly targeted to the membranes and insoluble fractions. Extensive degradation also occurred. Nonetheless, the fusion protein was partially purified from the soluble fraction by Ni-NTA and amylose resin affinity chromatography. Multiple proteins co-purified with DGAT1 fusion protein. These fractions appeared yellow in color and contained fatty acids. The rDGAT1 was solubilized from the insoluble fraction by seven detergents and urea, with SDS and Triton X-100 being the most effective detergents. The solubilized rDGAT1 was partially purified by Ni-NTA affinity chromatography. PreScission protease digestion confirmed the identity of rDGAT1 and showed extensive precipitation following Ni-NTA affinity purification. Conclusions: This study reports the first procedure for expressing full-length DGAT1 from any species using a bacterial expression system. The results suggest that recombinant DGAT1 is degraded extensively from the carboxyl terminus and associated with other proteins, lipids, and membranes. [ABSTRACT FROM AUTHOR]