Identification of a novel series of alkylitaconic acids in wood cultures of Ceriporiopsis subvermispora by gas chromatography/mass spectrometry.

A novel series of long-chain unsaturated dicarboxylic acids consisting of a long aliphatic chain attached to the C-3 position of itaconic acid has been identified by gas chromatography/mass spectrometry during in vitro decay of eucalypt wood by the white-rot basidiomycete Ceriporiopsis subvermispora. The major compounds were identified as tetradecyl-, 7-hexadecenyl- and hexadecylitaconic acids by their mass fragmentation patterns. Other members of the same compound series, identified as dodecanyl-, tridecanyl-, tetradecenyl-, pentadecanyl-, octadecenyl- and octadecanylitaconic acids, were present in very minor amounts or traces. Whereas hexadecenylitaconic acid has already been reported in cultures of C. subvermispora, to our knowledge this is the first report of the presence of the other alkylitaconic acids in fungal cultures. These new alkylitaconic-type metabolites may constitute a source for peroxidizable lipids involved in lignin degradation during wood decay by C. subvermispora and other white-rot basidiomycetes.     

Study of the reactions K−p → Λ0+ neutrals in the C.M. energy range from 1580 to 1750 MeV

Results on the channels K^?p → Λ⁰η⁰, Λ⁰π⁰, Σ⁰π⁰, Λ⁰π⁰π⁰ and Σ⁰π⁰π⁰ are obtained in a K^?p formation experiment using 1 million photographs taken in a heavy liquid bubble chamber filled with a CF₃BrC₃H₈ mixture. The results are compared with hydrogen bubble chamber (HBC) experiments and with experiments having full or partial gamma-ray detection. Our Λ⁰π⁰ and Λ⁰ + neutral cross section agree with HBC results. Our Σ⁰π⁰ cross section does not exhibit a bump at 1670 MeV as previously seen in HBC experiments. Our Λ⁰π⁰π⁰ data are dominated by a Σ(1385)π⁰ production. Our Σ⁰π⁰π⁰ data is consistent with the presence of some Σ(1405)π⁰ production.     

Multiparticle rapidity clustering in 200 GeV/cπ−p interactions

A study of multiparticle rapidity clustering is made using a generalized rapidity-gap method. The data for events with ?6 charged particles are compared to what would be expected from uncorrelated particle production. We find clear evidence for cluster production. The data are consistent with ～ 20% of all charged particles being produced in clusters of two charged particles; clusters of higher multiplicity are not required.