The glucosinolate profile of leaves and seeds of 33 Brassica napus L. crops, including leafy crops, forage, rutabaga, and oilseed crops, was compared by high-performance liquid chromatography to investigate the relation between the consumable product of each crop and the glucosinolate profile. Glucosinolate concentration was higher in seeds than in leaves, varying from 3.8-fold in oilseed crops to 7.1-fold in root vegetable crops. Aliphatic glucosinolates predominated in both organs. In seeds, aliphatic glucosinolates represented between 91% to 94% in the different groups, whereas in leaves there was more variation. For root vegetable crops, aliphatic glucosinolates represented 80% of the total glucosinolate concentration. For leafy and forage types, aliphatic glucosinolates represented approximately 90% and for oilseed crops represented 92%. Indole glucosinolates were more abundant in leaves (5% to 17%) than in seeds (5% to 8%). The total glucosinolate content in leaves ranged from 14 to 24 μmol·g−1 dry weight (DW) in oilseed and forage types, respectively, whereas in the seeds, it ranged from 55 to 115 μmol·g−1 DW in oilseed and forage types, respectively. Significant differences were noted among the four groups in glucosinolate concentration and glucosinolate composition. In the seeds, progoitrin was found as the main glucosinolate in all groups. In the leaves, two different glucosinolate profiles were found depending on the crop: forage and root vegetable crops showed high levels of progoitrin, whereas glucobrassicanapin was the main glucosinolate for oilseed and leafy crops. We suggest that different selection criteria applied on B. napus crops according to their use could have led to an indirect selection for glucosinolate profile in leaves.

A high temperature thermosetting bisphenol-A dicyanate (BADCy) was modified with polyetherimide (PEI) at various compositions. The effects of the morphology of the blends on the fracture toughness and mechanical properties were investigated. For this purpose, fracture, flexural, and compression tests were carried out. The fracture surfaces of the broken specimens were examined by scanning electron microscopy (SEM) and atomic force microscopy (AFM). The morphology was controlled by changing the curing conditions and PEI content. A good correlation between fracture properties and microstructural features of the mixtures has been observed. The phaseinverted morphologies showed the highest fracture toughness, which was further increased by increasing the cure temperature. The mechanical properties of the matrix (modulus, yield strength) were not affected by the addition of the thermoplastic. Fracture energy values show similar trends for the different mechanical tests performed.

A high-temperature thermosetting bisphenol-A dicyanate, BADCy was modified with polyetherimide, PEI, at various compositions. Phase separation and rheokinetics through curing were studied by optical microscopy, dynamic and isothermal differential scanning calorimetry, and rheological measurements. The PEI phase separated at the early stages of curing, well before gelation, and did not affect the polycyclotrimerization kinetics. The phase structure and thermal properties of the final network were investigated as a function of the PEI content and cure temperature. For this purpose, dynamic mechanical analysis, scanning electron microscopy studies, and thermogravimetrical analysis were carried out. The morphological changes were interpreted in terms of a spinodal decomposition mechanism in the composition range studied.

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The potential of near-infrared spectroscopy (NIRS) for screening the sinigrin, gluconapin, 4-hydroxyglucobrassicin, and total glucosinolate contents of Indian mustard (Brassica juncea L. Czern. & Coss.) seed was assessed. Intact seed samples of this species were analyzed by NIRS and their reference values regressed against different spectral transformations by modified partial least-squares (MPLS) regression. The coefficients of determination (r (2)) for sinigrin, gluconapin, 4-hydroxyglucobrassicin, and total glucosinolate contents were, respectively, 0.86, 0.95, 0.33, and 0.82. The standard deviation to standard error of prediction (SEP) ratio, and SEP to standard error of laboratory ratio were for these constituents as follows: sinigrin, 2.59 and 2.70; gluconapin, 4.16 and 2.08; 4-hydroxyglucobrassicin, 1.18 and 1.40; and total glucosinolates, 2.18 and 1.60. By comparison of commercial sinigrin spectrum with the first MPLS loadings of the sinigrin equation, it can be concluded that the molecule of sinigrin has a specific signal in the seed spectrum of Brassica.