Dynamics of radical cations of poly(4-hydroxystyrene) in the presence and absence of triphenylsulfonium triflate as determined by pulse radiolysis of its highly concentrated solution

Pulse radiolysis of highly concentrated poly(4-hydroxystyrene) (PHS) solutions in cyclohexanone and p-dioxane was performed both with and without an onium-type photoacid generator (PAG). With increasing PHS concentration, the rate constant of deprotonation of PHS radical cations was found to decrease. In the presence of PAG, the yield of the multimer radical cation of PHS was shown to decrease. We found that pairing between the anions produced by the attachment of dissociative electrons of PAGs and the monomer PHS radical cations restrict local molecular motions, leading to the formation of the multimer PHS radical cations

Metabolic Products of Aspergillus terreus. IV. Metabolites of the Strain IFO 8835. (2). The Isolation and Chemical Structure of Indolyl Benzoquinone Pigments

Eleven kinds of bisindolyl-dimethoxyl-p-benzoquinones, "asterriquinones A-1, A-2, A-3, A-4, B-1, B-2, B-3, B-4, C-1, C-2, and D"were isolated from Aspergillus terreus IFO 8835, and their structures were determined. Asterriquinone D had the basic structure, and the others were substituted with dimethylallyl group (s) in the indole ring

Demonstration of cytotoxicity against wasps by pierisin-1: a possible defense factor in the cabbage white butterfly.

The cabbage white butterfly, Pieris rapae, produces pierisin-1, a protein inducing apoptosis of mammalian cells. In the present study, the biological activity of pierisin-1 as a protective agent against parasitic wasps for P. rapae was examined. Pierisin-1 caused detrimental effects on eggs and larvae of non-habitual parasitoids for P. rapae, Glyptapanteles pallipes, Cotesia kariyai and Cotesia plutellae at 1-100 µg/ml, levels essentially equivalent to those found in P. rapae larvae. In contrast, eggs and larvae of the natural parasitoid of P. rapae, Cotesia glomerata proved resistant to the toxicity of pierisin-1 through inhibition of pierisin-1 penetration of the surface layer. The expression level of pierisin-1 mRNA in the larvae of P. rapae was increased by parasitization by C. plutellae, whereas it was decreased by C. glomerata. In addition, C. plutellae was associated with elevation of activated pierisin-1 in the hemolymph. From these observations, it is suggested that pierisin-1 could contribute as a defense factor against parasitization by some type of wasps in P. rapae