Seawater sampled from the Semarang port in Indonesia was streaked onto inorganic-medium plates coated with weathered crude oil, and 153 strains were isolated. Analyses of 16S rRNA gene sequences identified 67 different phylotypes affiliated with Alphaproteobacteria (111 strains/44 phylotypes), Gammaproteobacteria (8/8) and Actinobacteria (34/15). The organisms represented by 36 phylotypes could transform petroleum components in pure cultures. Many of them were affiliated with genera yet unrelated to hydrocarbon degradation. Strains unaffiliated with known genera were also obtained. Results suggest that many as-yet-unknown hydrocarbondegrading bacteria are present in tropical marine environments.

An aerobic, Gram-negative, motile bacterium, strain C02T , was isolated from seawater obtained from Semarang Port in Indonesia. Cells of strain C02 T were peritrichously flagellated and rodshaped. Strain C02 T was able to degrade naphthalene, alkylnaphthalenes and phenanthrene. 16SrRNA gene sequence analysis revealed that this strain was affiliated with the family Rhodobacteraceae in the class Alphaproteobacteria and was related most closely to Marinovum algicola FF3 T (95.7 % similarity) and Thalassobius aestuarii JC2049 T (95.2 %). The DNA G+C content of strain C02 T was 64.6 mol%. The major cellular fatty acids were C 18 : 1 v7c (50.9 % of the total), C 16 : 0 (17.9 %), 11 methyl C 18 : 1 v7c (14.7 %), C 18 : 1 v9c (2.9 %) and C 19 : 0 cyclo v8c (2.4 %), and the predominant respiratory lipoquinone was ubiquinone-10. Based on physiological, chemotaxonomic and phylogenetic data, strain C02 T is suggested to represent a novel species of a new genus, for which the name Tropicibacter naphthalenivorans gen. nov., sp. nov. is proposed. The type strain of Tropicibacter naphthalenivorans is C02 T (5JCM 14838Contamination of the marine environment with petroleum hydrocarbons is of great public concern owing to their toxicity to humans and marine organisms (Malins et al., 1985;Meador et al., 1995). A number of hydrocarbondegrading bacteria have been isolated from the marine environment and characterized (e.g. Kasai et al., 2002a, b;Ozaki et al., 2006), although information regarding hydrocarbon-degrading bacteria from tropical waters is relatively scarce (Chaillan et al., 2004;Zhuang et al., 2003;Zinjarde & Pant, 2002). We have recently isolated a substantial number of marine bacteria from seawater obtained from Semarang Port in Indonesia, and demonstrated that some of the isolates were capable of degrading hydrocarbons (Harwati et al., 2007). The present study characterizes one of these Indonesian isolates, designated strain C02 T , affiliated with the class Alphaproteobacteria. Based on the results of polyphasic examinations, including phenotypic, chemotaxonomic and phylogenetic analyses, we propose that this strain represents a novel species of a new genus.The ability of strain C02T to degrade hydrocarbons in crude oil was examined in 10 ml ONR7a medium (Dyksterhouse et al., 1995) supplemented with 1 mg heat-treated Arabian Light crude oil ml 21 (Dutta & Harayama, 2000). Cells of strain C02 T grown in 10 ml marine broth 2216 (MB; Difco) up to an optical density at 600 nm of approximately 1 were harvested by centrifugation (8000 g, 10 min), washed twice with ONR7a medium and inoculated on to the medium in 50-ml tubes fitted with Teflon-lined caps. The tubes were incubated at 30 u C on a reciprocal shaker (at 90 r.p.m.) for 4 weeks. Cultures were prepared in triplicate. Non-inoculated samples were incubated similarly and served as controls. Following incubation, oil components were extracted by using chloroform, and hydrocarbon losses were analysed via GC-MS (GC-MS-QP5000; Shimadzu) as described by Kasai et al. (2002b)...

An aerobic, Gram-negative, motile bacterium, strain B51T , was isolated from seawater obtained from Semarang Port in Indonesia. Cells of strain B51 T were peritrichously flagellated and rodshaped. Strain B51 T was able to degrade alkanes, branched alkanes and alkylnaphthalenes. 16SrRNA gene sequence analysis revealed that strain B51 T was affiliated with the family Rhodobacteraceae, and was related most closely to Thioclava pacifica TL 2 T (94.6 % similarity).The DNA G+C content of strain B51 T was 66.5 mol%. The major cellular fatty acids were C 18 : 1 v7c (84.9 %), C 18 : 1 v9c (13.8 %), C 16 : 0 (8.7 %), C 18 : 0 (6.4 %) and anteiso-C 15 : 0 (5.8 %) and the major quinone was ubiquinone-10. Based on its phenotypic and phylogenetic characteristics, strain B51 T is considered to represent a novel species of a new genus, for which the name Tropicimonas isoalcanivorans gen. nov., sp. nov. is proposed. The type strain of the type species is B51 T (5JCM 14837Contamination of the marine environment with petroleum hydrocarbons is of great public concern in terms of their toxicity to humans and marine organisms (Malins et al., 1985;Meador et al., 1995). A number of hydrocarbondegrading bacteria have been isolated from the marine environment and characterized (e.g. Kasai et al., 2002a, b;Ozaki et al., 2006), although information regarding hydrocarbon-degrading bacteria from tropical waters is relatively scarce (Chaillan et al., 2004;Zhuang et al., 2003;Zinjarde & Pant, 2002). We have recently isolated a substantial number of marine bacteria from seawater obtained from Semarang Port in Indonesia and demonstrated that some of the isolates were capable of degrading hydrocarbons (Harwati et al., 2007). Among them, strain B51 T , affiliated with the class Alphaproteobacteria, was able to degrade normal and branched alkanes (e.g. pristane and phytane) and alkylnaphthalenes (Harwati et al., 2007). In the present study, we describe the taxonomic characterization of strain B51T and suggest that it represents a novel species of a new genus.The cell morphology of strain B51T was examined by transmission electron microscopy (Beveridge et al., 1994) and motility was examined under a phase-contrast microscope. Gram staining and oxidase and catalase tests were performed according to the procedures of Smibert & Krieg (1994). Growth was tested at 30 u C in marine broth 2216 (MB; Difco) unless otherwise stated. Salinity requirements were tested by using modified MB (Sohn et al., 2004) supplemented with 0-20 % (w/v) NaCl at 30 u C. The pH range for optimal growth was determined on solid media containing MB whose pH was adjusted to 5.5-9.5. Solid media contained 1.5 % (w/v) Bactoagar (Difco). The presence of poly-b-hydroxyalkanoate was detected by using Sudan Black according to the procedures of de Lima et al. (1999). Susceptibility to antibiotics was determined on agar plates containing MB (MA plates) in the presence of the following antibiotics (concentrations given in parentheses; mg ml Microlog GN2 microplates (Biolog) were used for bi...

Cyanobacteria have been known as a potential extracellular-polysaccharide (EPS) producer. The objective of this study was to screen the marine cyanobacteria as potential antidiabetic agents. The present investigation was designed to determine the antidiabetic activity of EPS, intracellular-polysaccharide (IPS) and biomass extracts from marine cyanobacteria isolates. 10 cyanobacteria isolates were cultivated in IMK medium, at 25 o C for 21 days. The morphology of cells was identified by a light microscope. EPS and IPS were separated by ethanol precipitation method and their antidiabetic activity was analyzed by the inhibition of α-glucosidase activity method. Results of morphology identification of 10 cyanobacteria isolates consist of Oscillatoria limnetica, Oscillatoria sp., Leptolyngbya sp., Pseudanabaena sp., Lyngbya sp. and Phormidium sp., Coelastrella sp., Aphanothece sp. and Synechococcus sp., and Chroococcus sp. Almost all of EPS from marine cyanobacteria isolates were potential as inhibitor of α-glucosidase, except for Oscillatoria limnetica and Phormidium sp. isolates. The highest activity in α-glucosidase inhibition was detected in Pseudanabaena sp. (14.02%) and Chroococcus sp. (13.0%) isolates.