Improved Calibration for Estimating Soil Properties with a Multifunctional Heat Pulse Probe

A multifunctional heat pulse probe (MFHPP) can measure soil thermal and hydraulic properties. Though its successful implementation has been documented, previous studies have reported some limitations. One specific cause of the limitations is the absorption of the generated heat pulse within the probe itself, which creates error in the measurements. The objective of this study was to develop and evaluate a new calibration method to account for measurement error due to heat loss to the probe. A MFHPP was constructed and tested in six soil types using both a traditional method and the newly developed calibration method. The new calibration utilizes heat pulse response curves from real soils with thermal conductivities similar to that of the MFHPP rather than the traditional agar-stabilized water solution. This new approach significantly reduced average measurement errors from 9.1% to 2.4% for heat capacity and 13.5% to 4.5% for volumetric water content.     

Characterization of phytochemicals and antioxidant activities of a purple tomato (Solanum lycopersicum L.)

A newly developed nongenetically modified purple tomato V118 was investigated for its phytochemical compositions and antioxidant activities. A highly efficient and sensitive UPLC method was developed for both the phenolics and carotenoids, which showed that in addition to the phytochemicals commonly known for tomatoes, V118 had a unique composition of anthocyanins. The total carotenoid content of V118 was 234.78 μg/g dry weight (DW), and the total phenolic content was 659.11 mg GAE/100 g DW. The antioxidant activities of the lipophilic extract as measured by the PCL and ORAC-L assays were 30.11 μmol TE/g DW and 11.97 μmol TE/g DW, respectively, while the hydrophilic extracts as determined by the ORAC-H and FRAP assays were 323.23 μmol TE/g DW and 54.95 μmol AAE/g DW, respectively. The LC-MS study showed three major anthocyanins, which were mainly acylglycosides of petunidin and malvidin. This study showed that purple tomatoes such as V118 possess additional phytochemicals like anthocyanins, which can potentially have added health benefits.     

Hydroxycinnamoylmalic acids and their methyl esters from pear (Pyrus pyrifolia Nakai) fruit peel

Two novel caffeoylmalic acid methyl esters, 2-O-(trans-caffeoyl)malic acid 1-methyl ester (6) and 2-O-(trans-caffeoyl)malic acid 4-methyl ester (7), were isolated from pear (Pyrus pyrifolia Nakai cv. Chuhwangbae) fruit peels. In addition, 5 known hydroxycinnamoylmalic acids and their methyl esters were identified: 2-O-(trans-coumaroyl)malic acid (1), 2-O-(cis-coumaroyl)malic acid (2), 2-O-(cis-coumaroyl)malic acid 1-methyl ester (3), 2-O-(trans-coumaroyl)malic acid 1-methyl ester (4), and 2-O-(trans-caffeoyl)malic acid (phaselic acid, 5). The chemical structures of these compounds were determined by spectroscopic data from ESI MS and NMR. Of all the isolated compounds, five hydroxycinnamoylmalic acids and their methyl esters (2-4, 6, 7) were identified in the pear for the first time.     

Biofortification of soybean meal: immunological properties of the 27 kDa γ-zein

Legumes, including soybeans ( Glycine max ), are deficient in sulfur-containing amino acids, which are required for the optimal growth of monogastric animals. This deficiency can be overcome by expressing heterologous proteins rich in sulfur-containing amino acids in soybean seeds. A maize 27 kDa γ-zein, a cysteine-rich protein, has been successfully expressed in several crops including soybean, barley, and alfalfa with the intent to biofortify these crops for animal feed. Previous work has shown that the maize 27 kDa zein can withstand digestion by pepsin and elicit an immunogenic response in young pigs. By use of sera from patients who tested positive by ImmunoCAP assay for elevated IgE to maize proteins, specific IgE binding to the 27 kDa γ-zein is demonstrated. Bioinformatic analysis using the full-length and 80 amino acid sliding window FASTA searches identified significant sequence homology of the 27 kDa γ-zein with several known allergens. Immunoblot analysis using human serum that cross-reacts with maize seed proteins also revealed specific IgE-binding to the 27 kDa γ-zein in soybean seed protein extracts containing the 27 kDa zein. This study demonstrates for the first time the allergenicity potential of the 27 kDa γ-zein and the potential that this protein has to limit livestock performance when used in soybeans that serve as a biofortified feed supplement.     

Genetic manipulation for enhancing calcium content in potato tuber

Increased calcium (Ca) in potatoes may increase the production rate by enhancing tuber quality and storability. Additionally, increased Ca levels in important agricultural crops may help ameliorate the incidence of osteoporosis. However, the capacity to alter Ca levels in potato tubers through genetic manipulations has not been previously addressed. Here we demonstrate that potato tubers expressing the Arabidopsis H+/Ca2+ transporter sCAX1 (N-terminal autoinhibitory domain truncated version of CAtion eXchanger 1) contain up to 3-fold more Ca than wild-type tubers. The increased Ca appears to be distributed throughout the tuber. The sCAX1-expressing potatoes have normally undergone the tuber/plant/tuber cycle for three generations; the trait appeared stable through successive generations. The expression of sCAX1 does not appear to alter potato growth and development. Furthermore, increased Ca levels in sCAX1-expressing tubers do not appear to alter tuber morphology or yield. Given the preponderance of potato consumption worldwide, these transgenic plants may be a means of marginally increasing Ca intake levels in the population. To our knowledge, this study represents the first attempts to use biotechnology to increase the Ca content of potatoes.     

SNP Markers Discovery in Soybean with Use of Degenerate Oligolucleotide Primed PCR

There are several strategies that can be applied in SNP discovery, as for example the locus-specific amplification of target genome regions （Primmer et al., 2002; Van et al., 2004） or simultaneous assembly of anonymous sequences which are the product of whole genome shotgun sequencing （Webber and Myers, 1997） or reduced representation shotgun sequencing （Altshuler et al., 2000）. The majority of these methods are highly cost-prohibitive, however, and there is a necessity for development of new strategies that would be more suitable for small and medium-scale laboratories.     

Determination of chlorate and chlorite and mutagenicity of seafood treated with aqueous chlorine dioxide.

The use of chlorine dioxide (ClO(2)) as a potential substitute for aqueous chlorine to improve the quality of seafood products has not been approved by regulatory agencies due to health concerns related to the production of chlorite (ClO(2)(-)) and chlorate (ClO(3)(-)) as well as possible mutagenic/carcinogenic reaction products. Cubes of Atlantic salmon (Salmo salar) and red grouper (Epinephelus morio) were treated with 20 or 200 ppm aqueous chlorine or ClO(2) solutions for 5 min, and extracts of the treated fish cubes and test solutions were checked for mutagenicity using the Ames Salmonella/microsome assay. No mutagenic activity was detected in the treated fish samples or test solutions with ClO(2). Only the sample treated with 200 ppm chlorine showed weak mutagenic activity toward S. typhimurium TA 100. No chlorite residue was detected in sea scallops, mahi-mahi, or shrimp treated with ClO(2) at 3.9-34.9 ppm. However, low levels of chlorate residues were detected in some of the treated samples. In most cases, the increase in chlorate in treated seafood was time- and dose-related.     

Loss of pendimethalin in runoff and leaching from turfgrass land under simulated rainfall

A field study was undertaken to investigate runoff and leaching loss of the herbicide pendimethalin in turfgrass land of loamy sand soil. A series of plots constructed in a golf course fairway were surface-applied with pendimethalin SC formulation at the rate of 2. 25 or 4.50 kg a.i./ha and subjected to simulated rainfall at 2.0 cm/day for 10 consecutive days. Runoff losses of pendimethalin were the highest at the first rainfall and then gradually decreased with time. The first runoff event contained pendimethalin in its highest concentration, and in subsequent runoff samples the concentration decreased exponentially. The ranges of pendimethalin concentration were 80.9-18.2 and 177.4-48.6 microgram/L in the standard and double doses, respectively. Total losses by 20 cm of rainfall for 10 days reached 0.81 and 1.22% of the initial deposits at 2.25 and 4.50 kg a. i./ha, respectively. Pendimethalin concentration in the leachate collected at 30-cm soil depth was quite lower than that in the runoff, and the concentration rapidly decreased from 4.3-4.7 to 0. 2-0.4 microgram/L during the 10 days of rainfall treatment. Soil residue analysis at 45 and 90 days after pendimethalin treatment showed that more than 90% of the residue remained at the top 10 cm of soil depth. Low runoff and leaching confirmed that lateral and downward movement of the herbicide should be limited in turf soil. The half-life of pendimethalin under field conditions was 23-30 days and was not affected by application dose and rainfall treatment, but longer persistence was observed under laboratory conditions. Considering low runoff and leaching, as well as relatively short persistence in soil, it is concluded that little environmental carryover of pendimethalin would be expected in turfgrass land.     

The Use of Biofilters to Reduce Atmospheric Methane Emissions from Landfills: Part I. Biofilter Design

Previous laboratory research has shown that biofilters have the potential to reduce CH₄ emissions from landfills by as much as 83%. However, to achieve this level of CH₄ reduction biofilters must be properly designed. The present study was conducted to develop a method for properly designing biofilters based on landfill size and location. A quadratic equation was developed to describe the dependence of CH₄ oxidation rate in a sandy loam textured soil as a function of soil temperature, soil moisture and ammonium nitrogen concentration. Using this equation and the average monthly soil temperature and moisture contents for the largest cities of each of the 48 contiguous states, the monthly CH₄ oxidation rate at each location was calculated. Then, assuming a standard landfill depth of 27.6 m, and a standard area of 121,500 m², the required biofilter size was calculated. Finally, the ratio of biofilter size to landfill size was calculated. Design calculations for biofilters located in the states of Alabama, Florida, Georgia, Louisiana, Mississippi, North Carolina, South Carolina and Texas where the CH₄ oxidation rates are relatively high throughout the year indicate that the necessary biofilter sizes are small. In addition, biofilters in these states may be expected to be effective throughout the year. In contrast, the calculations indicated biofilter systems in the states of Idaho, Minnesota and North Dakota will have much lower efficiencies during much of the year due to unfavorable soil moisture and temperature ranges. Given proper design, installation and management, a biofilter should be capable of achieving a significant reduction in atmospheric CH₄ emission as compared to emissions from the same landfill without a biofilter.     

Chemical Composition Change in TSP Due to Dust Storm at Gosan, Korea: Do the Concentrations of Anthropogenic Species Increase Due to Dust Storm?

Aerosol composition change between dust storm and non-dust storm periods in spring is studied using the total suspended particle data measured at Gosan, a background area in Korea. The concentrations of eight inorganic ions and 12 elements were analyzed for the TSP samples collected from March 1992 to May 2006. Two-step statistical analyses were carried out for the data: F test and t test. The concentrations of anthropogenic ionic species showed increasing trend since 2003. The absolute concentrations of most anthropogenic species such as sulfate or nitrate increased (from 7.33 to 9.25 µg m^?3 and from 2.04 to 4.84 µg m^?3, respectively) during the dust storm period. However, the enrichment factors or normalized concentrations based on Al of most anthropogenic species decreased during dust storm period (factor of 0.1–0.5). It suggests that, in general, relative importance of anthropogenic species during dust storm would be not high.