LC-MS/MS quantitative analysis of reducing carbohydrates in soil solutions extracted from crop rhizospheres.

A simple, sensitive, and specific analytical method has been developed for the quantitative determination of 15 reducing carbohydrates in the soil solution of crop rhizosphere. Reducing carbohydrates were derivatized with 1-phenyl-3-methyl-5-pyrazolone, separated by reversed-phase high-performance liquid chromatography and detected by electrospray ionization tandem mass spectrometry. Lower limits of quantitation of 2 ng/mL were achieved for all carbohydrates. Quantitation was performed using peak area ratios (analyte/internal standard) and a calibration curve spiked in water with glucose-d(2) as the internal standard. Calibration curves showed excellent linearity over the range 2-100 ng/mL (10-1,000 ng/mL for glucose). The method has been tested with quality control samples spiked in water and soil solution samples obtained from the rhizosphere of wheat and canola and has been found to provide accurate and precise results.

Preparation and characterization of activated carbon derived from the thermo-chemical conversion of chicken manure.

Physico-chemical properties of a bioorganic char were modified by pyrolysis in the presence of NaOH, and with subsequent physical activation of carbonaceous species with CO2 a value-added activated carbon was fabricated. Bioorganic char is produced as a co-product during the production of bio-fuel from the pyrolysis of chicken litter. Untreated char contains approximately 37 wt% of C and approximately 43-45 wt% of inorganic minerals containing K, Ca, Fe, P, Cu, Mg, and Si. Carbonization and chemical activation of the char at 600 degrees C in the presence of NaOH in forming gas (4% H2 balanced with Ar) produced mainly demineralized activated carbon having BET (Brunauer, Emmett, and Teller) surface area of 486 m2/g and average pore size of 2.8 nm. Further physical activation with CO2 at 800 degrees C for 30 min resulted in activated carbon with BET surface area of 788 m2/g and average pore size of 2.2 nm. The mineral content was 10 wt%. X-ray photoelectron spectroscopy (XPS) indicated that the latter activation process reduced the pyrrolic- and/or pyridonic-N, increased pyridinic-N and formed quaternary-N at the expense of pyrrolic- and/or pyridonic-N found in the untreated char.