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Two copper(II) complexes with a benzothiazolesulfonamide ligand, [Cu(L)2(py)2] (1) and [Cu(en)2(L)2] (2) [HL is N-2-(4-methylbenzothiazole)toluenesulfonamide, py is pyridine, en is ethylenediamine], were prepared and then characterized with the aid of X-ray crystallography and spectroscopy. Whereas the copper(II) ion in 1 presents a square-planar geometry, in 2 it has a distorted octahedral environment. In addition, although the ligand is monodentate in both complexes, it exhibits different coordination behavior in each, interacting through the benzothiazole nitrogen atom in 1 and through the sulfonamide nitrogen atom in 2. The propensity for binding of 1 and 2 to calf thymus DNA was studied by thermal denaturation, viscosimetry, and cyclic voltammetry. The ability of the complexes to cleave DNA was studied in vitro through ascorbate activation and was tested by monitoring the expression of the yEGFP gene containing the RAD54 reporter. Moreover, their antiproliferative activity was verified in two cellular models: yeast and human tumor cells in culture. While 1 was found to be the more active cleaving agent in vitro, 2 showed a higher propensity for inflicting DNA damage at the cellular level. The biological studies carried out with human tumor cells, namely, colon adenocarcinoma Caco-2 cells (HTB-37) and leukemia Jurkat T lymphocytes (TIB-152), confirmed that both compounds inhibit the growth of these cell lines, although 2 is more effective. This difference is associated with the latter compound's greater ability to induce cell death by apoptosis.

Yeast strains present in 10 samples of kefir of different commercial and domestic origins have been isolated and classified taxonomically on the basis of the internal transcribed sequences (ITS) of their ribosomal RNA genes. A total of 18 yeast strains representing 10 different species have been characterized. Of the three commercial kefir samples analyed, two contained the well characterized yeast Kluyveromyces lactis while no yeast was found in the other one. A broader spectrum of yeast species was found among the home-made kefir samples, of which Issatchenkia orientalis, Saccharomyces unisporus, Saccharomyces exiguus and Saccharomyces humaticus were the most representative species.

Posidonia oceanica is an endemic Mediterranean seagrass species that has often been assumed to contain low levels of genetic diversity. Random amplified polymorfic DNA (RAPD) markers were used to assess genetic diversity among five populations from three geographical regions (north, central, and south) of the western Mediterranean Sea. Stranded germinating seeds from one of the central populations were also included in the analysis. Forty-one putative genets were identified among 76 ramets based on 28 RAPD markers. Genotypic diversity strongly depended on the spatial structure, age, and maturity of the meadows. The lowest clonal diversity was found in the less structured and youngest prairies. Conversely, a high genotypic diversity was found in the highly structured meadows. The genotypic diversity in these meadows was at the same level as in P. australis and higher than previously reported data for P. oceanica populations in the Tyrrhenian Sea near the coast of Italy.