Protease Treatment to Improve Ethanol Fermentation in Modified Dry Grind Corn Processes

To improve fractionation efficiency in modified dry grind corn processes, we evaluated the effectiveness of protease treatment in reducing residual starch in endosperm fiber. Three schemes of protease treatment were conducted in three processes: 1) enzymatic milling or E‐Mill, 2) dry fractionation with raw starch fermentation or dry RS, and 3) dry fractionation with conventional fermentation or dry conv. Kinetics of free amino nitrogen production were similar in both dry and wet fractionation (E‐Mill), indicating that proteolysis was effective in all three schemes. At the end of fermentation, endosperm fiber was recovered and its residual starch measured. Using protease treatment, residual starch in the endosperm fiber was reduced by 1.9% w/w (22% relative reduction) in dry conv and 1.7% w/w (8% relative reduction) in dry RS, while no reduction was observed in the E‐Mill process. Protease treatment increased ethanol production rates early in fermentation (≤24 hr) but final ethanol concentrations were unaffected in both dry RS and E‐Mill. In dry conv, the addition of protease resulted in a decline in final ethanol concentration by 0.3% v/v, as well as a higher variability in liquefaction product concentration (higher standard deviations in the glucose and maltose yields). Protease treatment can be used effectively to enhance modified dry grind processes.     

Origin of Gypsum-rich Coatings on Historic Buildings

Gypsum-rich coatings found on buildings constructed with granitic rock ashlars have been studied, from both an urban and a rural area of the NW of Spain. Previous works have attributed gypsum to rock weathering by atmospheric pollution. Mineralogical, chemical, and physical data of coatings have allowed us to distinguish six different types of coatings formed in several ways. In most cases, they are originated by the deterioration calcium-rich plaster building materials. Sulfation of Ca-rich coatings, in situ gypsum dissolution and precipitation, and deposition of air pollution particles are the most important agents related to genesis of coatings. In fact, remains of plasters practically intact were found in some studied buildings. Also, data from coatings and rock ashlars suggest that gypsum-rich coatings are not formed by environment–rock interaction. Coatings located on different parts and façades of the buildings and submitted to different environmental conditions decay in a different way.     

Monitoring suspended sediments and associated chemical constituents in urban environments: lessons from the city of Atlanta, Georgia, USA Water Quality Monitoring Program

Background, aim, and scope  The City of Atlanta, Georgia (COA) is part of the ninth largest metropolitan area in the USA and one of the fastest growing (e.g., >24% between 2000 and 2007). Since 2003, the US Geological Survey has been operating an extensive long-term water-quantity and water-quality monitoring network for the COA. The experience gained in operating this network has provided insights into the challenges as well as some solutions associated with determining urban effects on water quality, especially in terms of estimating the annual fluxes of suspended sediment, trace/major elements, and nutrients. Discussion and findings  The majority (>90%) of the annual fluxes of suspended sediment and discharge (>60%) from the COA occur in conjunction with stormflow. Typically, stormflow averages ≤20% of the year. Normally, annual flux calculations employ a daily time-step; however, due to the “flashy” nature of the COA’s streams, this approach can produce substantial underestimates (from 25% to 64%). Greater accuracy requires time-steps as short as every 2 to 3 h. The annual fluxes of ≥75% of trace elements (e.g., Cu, Pb, Zn), major elements (e.g., Fe, Al), and total P occur in association with suspended sediment; in turn, ≥90% of the transport of these constituents occurs in conjunction with stormflow. With the possible exception of nitrogen, baseflow sediment-associated and both baseflow and stormflow dissolved contributions represent relatively insignificant portions of the total annual load; hence, nonpoint (diffuse) sources are the dominant contributors to the fluxes of almost all of these constituents.     

Would you be happier if you were richer? A focusing illusion

The belief that high income is associated with good mood is widespread but mostly illusory. People with above-average income are relatively satisfied with their lives but are barely happier than others in moment-to-moment experience, tend to be more tense, and do not spend more time in particularly enjoyable activities. Moreover, the effect of income on life satisfaction seems to be transient. We argue that people exaggerate the contribution of income to happiness because they focus, in part, on conventional achievements when evaluating their life or the lives of others.     

Mass spectrometric evidence for the existence of oligomeric anthocyanins in grape skins

The fractionation of a grape skin extract by multilayer countercurrent chromatography coupled with step gradient elution allowed the preparation of a fraction almost devoid of free anthocyanins. This fraction appeared to be almost exclusively polymeric, as judged by liquid chromatographic-mass spectrometric (LC-MS) analysis, color-bleaching tests with sulfur dioxide, and thiolysis. Electrospray mass spectrometric analysis indicated that the pigmented material in this fraction was chiefly composed of direct condensation products of anthocyanin extending up to trimers. With regard to their linkages, the anthocyanin units in the oligomers were possibly linked by either an A-type (by both carbon-carbon and ether bonds) or B-type (by carbon-carbon bond) linkage, like proanthocyanidins. The terminal anthocyanin unit of the oligomers is consistently in the flavylium form but the extension units are in the flavan form for the A-type oligomers and in the flavene form for the B-type oligomers. Although their linkages still need to be defined rigorously, this is the first mass spectrometric evidence confirming the existence of anthocyanin oligomers in the grape skin extract.     

Fractionation of grape anthocyanin classes using multilayer coil countercurrent chromatography with step gradient elution

Grape anthocyanins from rosé wine pomace and grape skins were fractionated by multilayer coil countercurrent chromatography (MLCCC). Tert-butyl methyl ether/n-butanol/acetonitrile/water acidified with trifluoroacetic acid (2/2/x/5) was chosen as the solvent system because of its demonstrated efficiency in separating anthocyanins. A method combining MLCCC and step gradient elution has been developed. This method enabled the fractionation of anthocyanins as series of glucosides, and the corresponding acetylated, coumaroylated, and caffeoylated derivatives. The different anthocyanins were identified on the basis of their UV spectra, their elution time on reversed-phase HPLC as well as by mass spectrometry. A polar-colored fraction free of anthocyanin monomers and corresponding to the material remaining in the stationary phase after the completion of the gradient was recovered.     

Temporal Oscillation and Losses of Three Carbon Forms in a Microcatchment of NW Spain

Long-term agricultural sustainability and water quality may be threatened by inadequate land management. Carbon (C) losses at the catchment scale largely depend on land use and management practices. In “Abelar” farm (A Coruña, NW Spain), swine slurry was directly discharged during a period of about 30 years onto agricultural maize fields and rangeland under cattle production. In 1998, the agricultural fields and rangeland were planted to stands of Eucalyptus globulus. The purpose of this work was to assess the concentrations and losses of total, inorganic, and organic carbon at the outlet of a small catchment (10.7 ha) in the period from March 2007 to December 2010. Nearly 190 water samples were collected; specifically eleven in 2007, sixty-eight in 2008, fifty-six in 2009, and fifty-three in 2010. Total runoff volumes from the catchment were also measured during the 3.7-year study period. Except for a peak recorded in November 2008, total carbon values (TC) ranged from 1.51 to 6.14 mg L^?1, total inorganic carbon (TIC) varied between 0.54 and 3.30 mg L^?1, and total organic carbon (TOC) was between 0.38 and 2.83 mg L^?1; the exception was due to an occasional pig slurry discharge occurring in 2008, which drove the greatest values of the three carbon forms. The season of the year influenced concentrations of total, organic, and inorganic carbon. Total, organic, and inorganic carbon loads exported at the catchment outlet were estimated at the monthly and yearly time scales. Overall, 10 years after planting to the forest, dissolved and total carbon losses were rather small.     

Effects of fly ash on microbial C02 evolution from an agricultural soil

Unweathered, acidic fly ash from a coal-fired power plant was applied to alfalfa meal-amended agricultural soil at levels equivalent to 0, 100, 400, and 700 tonne ha^?1. Amended soils were placed in respirometer jars and monitored for C0₂-C evolution over a 37-day period. Fly ash applications of 400 and 700 tonne ha^?1 reduced C0₂-C production significantly compared to 0 and 100 tonne ha^?1 treatments. Carbon dioxide-carbon from all treatments was considerably greater than that from soil treated with 1000 ppm CdCl₂. The results suggest that soil heterotrophic microbial activity may be impacted minimally by relatively low levels of fly ash application, but may be inhibited by higher levels of fly ash. Several metals were present at potentially toxic levels in the fly ash employed and may have accounted for the inhibition of CO₂ C evolution. The availability of some of these metals was indicated in companion plant uptake experiments.