Biodiesel from algae is considered an alternative for a third generation of biofuels.However, most microalgae are not lipogenic during fast growth periods, but high lipid content occurs at resting stages. Microalgae biomass production for biodiesel needs continuous high volumetric and aerial yields and large amount of neutral lipid in the biomass. These requirements are similar to demanding a marathon runner to be obese. We show that by using cell--sorting capabilities of flow cytometers, in combination with the lipid--soluble fluorescent dye Nile Red, we can isolate and select cells with a high and stable lipid content. In our study we were able to select through three sorting events obtained from wild populations of Tetraselmis suecica

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Extracts from 44 species of seaweed from Gran Canaria (Canary Islands, Spain) were screened for the production of antibacterial and antifungal compounds against a panel of Gram-negative and Grampositive bacteria, mycobacteria, yeasts and fungi. A total of 28 species displayed antibacterial activity, of which six also showed antifungal activity. Asparagopsis taxiformis and Cymopolia barbata were the species with the strongest activities against the broadest spectrum of target microorganisms. All the species with antibacterial activity were active against Gram-positive bacteria, whereas only two species, A. taxiformis and Osmundea hybrida, were active against mycobacteria. The production of secondary metabolites with antimicrobial activities by the macroalgae was also studied under dierent conditions, although no common trend for bioactivity was observed.

SUMMARYThe aim of this study was to characterize the antigen specificity and to evaluate the diagnostic and prognostic value of anti-mitochondrial M5 type antibodies (AMA M5). Fifty-eight patients selected on the basis of their AMA M5 positivity were investigated in relationship to their clinical and serological profile. Cross-absorption studies, Western blotting and immunoprecipitation analysis were carried out for AMA M5 antigen specificity characterization. Most patients had a diagnosis of systemic lupus erythematosus (SLE) (65·5%) or of primary anti-phospholipid syndrome (PAPS) (24%); all the patients were positive for IgG or IgM anti-cardiolipin (anti-CL) antibodies and 49% of them also displayed lupus anticoagulant (LA) activity. Anti-b 2 -glycoprotein I (b 2 -GPI) IgG were detectable in 30/38 sera (78·9%) and IgM in 34/38 (89·4%). While anti-CL and anti-b 2 -GPI IgG antibodies were significantly associated with history of thrombosis and fetal loss, AMA M5 displayed a statistical association only for thrombocytopenia and recurrent fetal loss. Absorption with human b 2 -GPI both in free solution or in solid phase as well as with CL liposomes or CL/b 2 -GPI liposome complexes did not affect AMA M5 fluorescence. While AMA M5 activity is absorbed by whole mitochondrial preparations, no specific reactivities against several human, bovine and rat mitochondrial proteins could be detected in Western blotting and immunoprecipitation studies. AMA M5 appear to be detectable in both primary and secondary APS, displaying a strong association with the presence of thrombocytopenia and fetal loss. Although strictly related to anti-phospholipid antibodies, AMA M5, anti-CL and anti-b 2 -GPI antibodies represent distinct serological markers of the APS.

Abstract. Polypeptides of 21, 36 and 37 kDa are induced in the unicellular green alga Chlamydomonas reinhardtii Dang. when cells are transferred from high (2%) to low (0.03%) CO2 concentrations. The synthesis of these polypeptides is correlated with the induction of the CO2-concentrating mechanism. In this work we studied the effect of the growth conditions on the synthesis of these polypeptides with the aim of clarifying whether the induction of all three of these low-CO2-inducible polypeptides requires the same environmental factor. Our results showed that induction of the 21-and 36-kDa polypeptides under low-CO2 conditions occurred only in the light, while the 37-kDa periplasmic carbonic anhydrase (EC 4.2.1.1) was induced in light, darkness, and in both synchronous and asynchronous cultures. In addition, induction of these polypeptides appeared to be determined more by the O2/CO2 ratio than by the CO2 concentrations. None of these polypeptides could be induced in either of two different mutants of C. reinhardtii, one lacking ribulose-l,5-bisphosphate carboxylase/oxygenase (EC 4.1.1.39) and the other with inactive enzyme, Our results indicate that the 21-and 36-kDa polypeptides are regulated by a mechanism different from that controlling the 37-kDa polypeptide.