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A combination of LC–MS/MS and feature-based molecular networking analyses led to the isolation of a new adenopeptin analog, higapeptin (1), and four known peptides, adenopeptin (2), adenopeptins B and C (3 and 4), and acremopeptin (5), from the rice culture of the fungus Acremonium persicinum (18F04103) isolated from a mud flat of the Ariake Sea in Kyushu, Japan. The structure of 1 was determined by NMR and MS/MS fragmentation analyses. The absolute configuration of the constituent amino acids was determined by Marfey's analysis after acid hydrolysis. The C-terminal residue was synthesized, and its absolute configuration was established by Marfey's analysis. Compounds 1 and 2 were found to inhibit mitochondrial energy metabolism, similar to efrapeptin D (6), a known mitochondrial ATPase inhibitor. [ABSTRACT FROM AUTHOR]

A new monoacylglyceryltrimethylhomoserine, 21F121-A (1), was isolated from the culture of Penicillium glaucoroseum (21F00121) by LCMS-guided purification. The structure was elucidated by NMR and mass spectrometries. The absolute configuration of the homoserine moiety was analyzed by the ECD spectrum after acid hydrolysis, and the S-configuration of the glycerol moiety was determined based on the spectrum of the 1,2-dibenzoyl derivative after acid hydrolysis. Although a variety of diacylglyceryltrimethylhomoserine is distributed in lower plants and fungi, a limited number of studies on monoacyl derivatives have been reported. This is the fourth sample of monoacylglyceryltrimethylhomoserine discovered from a natural source, and the second sample isolated from a fungus. Compound 1 contains an unusual branched pentaene chain attached at the sn-1 position of glycerol and weakly inhibited the growth of HCT116 cells. [ABSTRACT FROM AUTHOR]

SWNTs were synthesized by laser-vaporized CCVD (catalytic chemical vapor deposition). The diameter distributions and the abundance of SWNTs synthesized at different temperatures and using different catalysts were investigated by Raman spectroscopy. Further, this technique was compared with other synthesis techniques (laser-oven and conventional-alcohol CCVD), and C was synthesized simultaneously as a byproduct only using the laser-oven technique. With increasing synthesis temperature, the diameter distribution shifted towards larger diameters, and the G/D ratio became larger as the synthesis temperature increased to 1000°C. Ni, Co, and Fe played a catalytic role, though Fe was less effective under our experimental conditions. The diameter distribution of SWNTs synthesized with the Fe catalyst was shifted to smaller values compared to those synthesized with Ni or Co catalysts. [ABSTRACT FROM AUTHOR]