Estimating Legacy Soil Phosphorus Impacts on Phosphorus Loss in the Chesapeake Bay Watershed.

Agricultural nutrient management is an issue due to P loss from fields and water quality degradation. This is especially true in watersheds where a history of P application in excess of crop needs has resulted in elevated soil P (legacy P). As practices and policy are implemented in such watersheds to reduce P loss, information is needed on time required to draw down soil P and how much P loss can be reduced by drawdown.

Phytochemical, antioxidant, and antiproliferative properties of seed oil and flour extracts of Maryland-grown tobacco cultivars.

To determine the possible alternative use of tobacco, the seeds representing seven Maryland tobacco cultivars were investigated for their phytochemical, antioxidant, and antiproliferative properties. Tobacco seed oils were extracted by the Soxhlet method, and analyzed for their yield, density, refractive index, fatty acid profiles, and tocopherol profile. The defatted flours were extracted in 50% acetone and 80% ethanol.

Tobacco biomass hydrolysate enhances coenzyme Q10 production using photosynthetic Rhodospirillum rubrum.

Coenzyme Q10 (CoQ10), a potent antioxidative dietary supplement, was produced using a photosynthetic bacteria Rhodospirillum rubrum ATCC 25852 by submerged fermentation supplemented with tobacco biomass hydrolysate (TBH) in comparison with media supplemented with hydrolysates prepared with alfalfa (ABH) or spinach (SBH). Growth medium supplemented with 20% (v/v) TBH was found favorable with regard to cell density and CoQ10 concentration. The stimulation effects on cell growth (shortened lag phase, accelerated exponential growth, and elevated final cell concentration) and CoQ10 production (enhanced specific CoQ10 content per unit cell weight) could be attributed to the presence of solanesol, the precursor of CoQ10, in the tobacco biomass.

Recovery of solanesol from tobacco as a value-added byproduct for alternative applications.

Solanesol in the waste streams of a bioprocess designed for alternative applications of low-alkaloid tobacco was recovered using three different extraction methods. Compared to the conventional heat-reflux extraction (HRE) and ultrasound-assisted extraction (UAE), microwave-assisted extraction (MAE) using 1:3 hexane:ethanol (v/v) as the solvent after saponification treatment of tobacco biomass was found the most effective in terms of solanesol yield, processing time, and volume of solvent consumed. Quantification of solanesol was achieved by optimizing the mobile phase at 60/40 acetonitrile-isopropanol and lowering the oven temperature to 22 degrees C using a standard reverse-phase high performance liquid chromatography (RP-HPLC).