The new marine Halomonas sp. strain GWS-BW-H8hM (DSM 17996) was found to produce 3-(4'-hydroxyphenyl)-4-phenylpyrrole-2,5-dicarboxylic acid (HPPD-1) and 3,4-bis(4'-hydroxy- phenyl)pyrrole-2,5-dicarboxylic acid (HPPD-2). In initial cultivations using marine broth, only low contents of these compounds have been isolated. Improving the conditions and growing the strain on artificial seawater supplemented with tryptone 10 g l(-1), yeast extract 5 g l(-1), L-tyrosine 0.6 g l(-1), glycine 1 g l(-1), and glucose 6 g l(-1), the growth-associated HPPD-1 and HPPD-2 production of a 40-l batch cultivation reached the amounts of 47 mg l(-1) and 116 mg l(-1), respectively, after 65 h. Both compounds showed potent anti-tumor-promoting activities.

The marine Microbacterium species HP2 (DSM 12583), isolated from the sponge Halichondria panicea, is able to produce a glucosylmannosyl-glycerolipid when grown on a complex medium with glucose. Optimizing the carbon sources in shake flask experiments has shown that glycerol affords the highest specific glycoglycerolipid production. The product yield approached 300 mg/L or 25 mg/g biomass upon scaling up in a 40-L bioreactor volume. The native diglycosyl-glycerolipid GGL.2 strongly inhibited growth of the tumor cell lines HM02 and Hep G2 (50% inhibition at 0.4 to 3 microg/mL), while the related deacylated compound (GG.2) showed a potent anti-tumor-promoting activity.