One new betaenone, theissenoic acid (1), together with three new acetogenins, theissenolactones A-C (2-4, resp.), were isolated from the fermented broth of Theissenia cinerea 89091602 isolated in Taiwan. The structures of 1-4 were elucidated by spectroscopic methods. Biological tests revealed that 3 and 4 exhibited moderate growth-inhibitory activities against A549 lung cancer cell line with GI(50) values of 14.9 and 47.9 μM, respectively.

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23 Steroid estrogens modulate physiology and development of vertebrates. Biosynthesis of C 18 24 estrogens from C 19 androgens by the O 2 -dependent aromatase is thought to be irreversible. Here, we 25 report a denitrifying Denitratisoma sp. strain DHT3 capable of catabolizing estrogens or androgens 26 anaerobically. Strain DHT3 genome contains a polycistronic gene cluster emtABCD differentially 27 transcribed under estrogen-fed conditions. emtABCD encodes a cobalamin-dependent 28 methyltransferase system conserved among estrogen-utilizing anaerobes; emtA-disrupted strain 29 DHT3 can catabolize androgens but not estrogens. These data, along with the observed androgen 30 production in estrogen-fed strain DHT3 cultures, indicate the occurrence of a cobalamin-mediated 31 estrogen methylation to form androgens. Consistently, the estrogen conversion into androgens in 32 strain DHT3 cell-extracts requires methylcobalamin and is inhibited by propyl-iodide, a specific 33 inhibitor of cobalamin-dependent enzymes. The identification of the cobalamin-mediated estrogen 34 methylation thus represents an unprecedented metabolic link between cobalamin and steroid 35 metabolism and suggests that retroconversion of estrogens into androgens occurs in the biosphere. 36 37

Four new lactone chlorins, ficuschlorins A - D (1-4, resp.), and six known pheophytins were isolated from the leaves of Ficus microcarpa. The structures of these compounds were determined by 1D- and 2D-NMR spectroscopy, and other techniques. New natural pheophytins were rarely obtained. In the past ten years, only three new pheophytins were isolated from natural sources.

Aconitum carmichaeli Debx. is a traditional Chinese medicine commonly employed for curing a wide array of diseases in East Asia. From the ethyl acetate soluble fraction of the methanolic extracts of A. carmichaeli, a new alkaloid, aconitamide (1), along with eighteen known compounds 2-19 were isolated by column chromatography and identified on the basis of spectroscopic analyses. The anti-telomerase activity of 1-19 was also assessed, but no activity was found, even at a concentration higher than 30 M.