Interactions of Bacillus Mojavensis and Fusarium Verticillioides With a Benzoxazolinone (Boa) and Its Transformation Product, Apo

En:Journal of Chemical Ecology (2007, vol. 33, n. 10, p. 1885-1897)The benzoxazolinones, specifically benzoxazolin-2(3H)-one (BOA), are important transformation products of the benzoxazinones that can serve as allelochemicals providing resistance to maize from pathogenic bacteria, fungi, and insects. However, maize pathogens such as Fusarium verticillioides are capable of detoxifying the benzoxazolinones to 2-aminophenol (AP), which is converted to the less toxic N-(2-hydroxyphenyl) malonamic acid (HPMA) and 2-acetamidophenol (HPAA). As biocontrol strategies that utilize a species of endophytic bacterium, Bacillus mojavensis, are considered efficacious as a control of this Fusarium species, the in vitro transformation and effects of BOA on growth of this bacterium was examined relative to its interaction with strains of F. verticillioides. The results showed that a red pigment was produced and accumulated only on BOA-amended media when wild type and the progeny of genetic crosses of F. verticillioides are cultured in the presence of the bacterium. The pigment was identified as 2-amino-3H-phenoxazin-3-one (APO), which is a stable product. The results indicate that the bacterium interacts with the fungus preventing the usual transformation of AP to the nontoxic HPMA, resulting in the accumulation of higher amounts of APO than when the fungus is cultured alone. APO is highly toxic to F. verticillioides and other organisms. Thus, an enhanced biocontrol is suggested by this in vitro study. =580 $aEn:Journal of Chemical Ecolog

Assay for plasma 25-hydroxyvitamin D2 and 25-hydroxyvitamin D3 by "high-performance" liquid chromatography.

Abstract We describe a new, rapid, and simple column-chromatographic procedure for 25-OH vitamin D3 in plasma. The vitamin is extracted by use of Sep-pak C18 (octadecyl alkylated silicic acid), a short factory-packed reversed-phase column, and 25-OH vitamin D2 + 25-OH vitamin D3 fraction is eluted with methanol/water. The 25-OH D2 and 25-OH D3 are then well resolved on a high-resolution 3-micrometer silicic acid straight-phase liquid-chromatography column. The peaks are quantified against a 25-OH D3 standard by ultraviolet absorbance. Recovery was assessed by use of tritiated 25-OH D3. The within-assay coefficient of variation of the method was 5% and recovery 93%. The method was evaluated with 26 samples from control subjects and 17 samples from patients, seven with liver disease and 10 who had undergone ileo-ileostomy for hypercholesterolemia. The normal seasonal variation was observed for 25-OH D3 concentrations, and they correlated negatively and significantly with those of 25-OH D2. Post-ileo-ileostomy concentrations of 25-OH D3 in plasma were generally similar to those in normal individuals for the same reason (winter), but 25-OH D2 concentrations were insignificantly lower. The patients with chronic liver disease had significantly lower 25-OH D3 concentrations than normal persons but higher 25-OH D2 concentrations, with a significantly higher 25-OH D2/25-OH D3 ratio, indicating poor storage of vitamin D3.</jats:p

Genetic trends in growth, sexual maturity and skeletal deformations, and rate of inbreeding in a breeding programme for rainbow trout (Oncorhynchus mykiss)

Nimekkeen selvennys: Genetic improvement.v2005o