In the process of screening for squalene synthase inhibitors from microbial fermentation products we have isolated a novel compound, named schizostatin (Fig. 1), from the culture broth of the mushroom, Schizophyllum communeSANK17785. Schizostatin inhibited rat liver microsomal squalene synthase dose dependently and the IC50 value was 0.84/^m. The inhibition was competitive with respect to farnesylpyrophosphate with a Ki value of 0.45 jllm.

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Schizostatin (1) has been isolated as a potent and selective inhibitor of squalene synthase. Its structure has been determined using spectroscopic methods: the compound is shown to be a diterpenoid which has a /r

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In search for new zaragozic acids and their derivatives that are potent inhibitors of squalene synthase, discomycetes of the order Leotiales were cultured and their fermentation broth was assayed, Three strains in 2 unidentified species of Mollisia were found to produce zaragozic acid D3 and three new analogs (F-lO863s), Fermentative production, productivity of F-10863s and mycological characteristics of the producers are described. Discomycetes are expected to be a biological resource providing novel bioactive compounds,

LC-MS and molecular networking analyses of the extract of the marine sponge Psammocinia sp. indicated the presence of two new compounds with multiple halogens. LC-MS-guided isolation yielded cyclic peptides, cyclopsammocinamides A (1) and B (2), in an enantiomeric relationship to cyclocinamide A (3). Planar structures of 1 and 2 were elucidated by NMR and mass spectroscopic analyses and the absolute configurations of the amino acid residues were determined using Marfey's method with their acid hydrolysates. The sponge extract exhibited cytotoxicity and the bioassay-guided isolation afforded a dimeric dilactone macrolide, swinholide A, as the cytotoxic compound.

A gynandromorph adult of the lawn ground cricket Polionemobius mikado (Shiraki, 1913) (Orthoptera: Trigonidiidae) was collected from a natural population. It had complete male forewings and a female ovipositor at the end of abdomen. A normal male that encountered the gynandromorph performed a courtship song and tried to transmit a spermatophore, whereas a normal female was indifferent to the gynandromorph. The gynandromorph showed aggressive behavior toward the normal male but not against the normal female. The gynandromorph raised its forewings immediately after the antenna touched the body of the normal male and female, but no sound was produced. Overall, the gynandromorph behaved as a male, but was courted by conspecific males. Thus, the sexual identity of the gynandromorph was masculine, but sexual attractiveness was feminine.

Comparison in acetaldehyde production by flesh discs was made to elucidate cultivar diffrences between 'Denkuro' and 'Hiratanenashi' persiommons with respect to the ease of removing their astringency. Soaking of flesh discs of immature astringent fruits in buffer containing ethanol caused more acetaldehyde production in 'Hiratanenashi' than in 'Denkuro'. When 4-methylpyrazole, an alcohol dehydrogenase inhibitor, was added to the same buffer, acetaldehyde production was partly inhibited in 'Hiratanenashi' discs, but not in those of 'Denkuro'. The addition of pyruvate or malate to the buffer increased acetaldehyde production in both cultivars, but at the same substrate level, discs of 'Denkuro' produced more acetaldehyde than did those of 'Hiratanenashi'; higher concentrations of pyruvate or malate tended to inhibit the reaction. The results indicate that 'Hiratanenashi' converts ethanol to acetaldehyde more efficiently than does 'Denkuro', whereas ' Denkuro' metabolizes pyruvate more readily to acetaldehyde than does 'Hiratanenashi'.