Two new compounds, asperversin A (1) and 9ξ-O-2(2,3-dimethylbut-3-enyl)brevianamide Q (2), and nine known compounds, brevianamide K (3), brevianamide M (4), aversin (5), 6,8-di-O-methylnidurufin (6), 6,8-di-O-methylaverufin (7), 6-O-methylaverufin (8), 5α,8α-epidioxyergosta-6,22-dien-3β-ol (9), ergosta-7,22-diene-3β,5α,6β-triol (10), and 6β-methoxyergosta-7,22-diene-3β,5α-diol (11), were obtained from the culture of Aspergillus versicolor, an endophytic fungus isolated from the marine brown alga Sargassum thunbergii. The structures of these compounds were established by spectroscopic techniques. Compounds 4, 7 and 8 exhibited antibacterial activities against Escherichia coli and Staphyloccocus aureus, and 7 also showed lethality against brine shrimp (Artemia salina) with an LC50 value of 0.5 μg/mL.

No abstract

Abstract. In this study, four strains of Chlorella genus and four strains of Tetraselmis genus were investigated to research their in vitro hydrogenase activities and hydrogen productions. C.sp.-3 showed the second highest in vitro hydrogenase activity with 297.48 nmol H 2 /(µg Chla h) and the highest volume of H 2 production with 10.246 µl/L among all the strains. Although T. sp.-3 exhibited a much low H 2 production of 0.298 µl/L, its in vitro hydrogenase activity was the highest with 315.92 nmol H 2 /(µg Chla h). During the continuous culture of five weeks, the hydrogen production of C. sp.-3 reached the peak at 3rd weeks with 12.46 µl H 2 per liter culture, and decreased subsequently. In contrast, that of T. sp.-3 increased slowly and gradually with the culturing time, and was much lower than that of C. sp.-3 at each culture phases. These results showed that hydrogen production was a complex process that was determined not only by strain types but also by other factors, and that both C.sp.-3 and T. sp.-3 in the 8 strains were the most promising ones in hydrogen production and were worthy of further research.