Paola Cennamo

Mitochondrial Cytochrome b DNA Sequence Variations: An Approach to Fish Species Identification in Processed Fish Products

The identification of fish species in food products is problematic because morphological features of the fish are partially or completely lost during processing. It is important to determine fish origin because of the increasing international seafood trade and because European Community Regulation 104/2000 requires that the products be labeled correctly. Sequence analysis of PCR products from a conserved region of the cytochrome b gene was used to identity fish species belonging to the families Gadidae and Merluccidae in 18 different processed fish products. This method allowed the identification of fish species in all samples. Fish in all of the examined products belonged to these two families, with the exception of one sample of smoked baccalà (salt cod), which was not included in the Gadidae cluster.

A SURVEY OF THE ALGAL FLORA OF ANTHROPOGENIC CAVES OF CAMPI FLEGREI (NAPLES, ITALY) ARCHEOLOGICAL DISTRICT

Campi Flegrei is a large volcanic area situated northwest of Naples, Italy. Two archeological sites, the Sybils Cave and the Piscina Mirabilis, are artificial caves dug in the yellow tuff and used during antiquity for various purposes. This paper describes for the first time the algal biodiversity of these caves and determines whether environmental factors such as light intensity and humidity are influential in species distribution. A total of twenty-two algal species were identified by molecular methods (18S rDNA); the largest group was Cyanobacteria (eleven species), followed by algae Chlorophyta (six), Rhodophyta (two) and Bacillariophyta (two). Cluster analysis of algal distribution in the caves in relation to light and humidity showed no relevant differences in algal distribution between the two caves. Three different algal groups were identified. The first one includes strains strictly dependent on low humidity, a second cluster was mainly associated with sites where humidity is not a severe constraint, and a third group, mainly represented by filamentous cyanobacteria, is probably dependent on high humidity, since it was detected only at Piscina Mirabilis.

Biofilms in churches built in grottoes

We investigated microorganisms dwelling on rocks, walls and paintings in two votive chapels built in grottoes in the Region of Campania, Italy. One grotto was near the coast in an area with a Mediterranean climate, and the other grotto was inland on a mountain in an area with a cold continental climate. Color and distribution of biofilms in various areas of the grottoes were examined. Microbial components of biofilms were identified by light and electron microscopy and by molecular techniques (DNA analyses and Automatic rRNA Intergenic Spacer Analysis). Biofilms were also analyzed by X-ray diffraction to detect inorganic constituents deriving from rocks in the grottoes and walls of the churches and by X-ray fluorescence to detect the elements that made up the pigments of the mural paintings; optical cross sections were used to observe their relationships with substrata. Species of eubacteria, cyanobacteria and green algae were identified. Some of these species occurred in both grottoes, while others were exclusive to only one of the grottoes. The diversity of species, their common or exclusive occurrence in the grottoes, the relationships among microbial communities and the differences in color and distribution of biofilms were discussed on the basis of the different climatic factors affecting the two grottoes and the different inorganic components of substrata.

Influences of geochemical and mineralogical constraints on algal distribution in acidic hydrothermal environments: Pisciarelli (Naples, Italy) as a model site

We consider Pisciarelli (Campi Flegrei, Italy) as a model site for investigating the factors which influence the distribution of microalgae in hydrothermal environments. This hydrothermal system is liquid-dominant with very low pH values both in water and in the soil; spring water has a temperature of up to 92 °C. At Pisciarelli, chemico-physical conditions are extremely variable in different sites, seasons and years. Five ecological stations were identified on the basis of temperature, pH and fluid vents conditions. Different algal communities have been observed according to their adaptability to these controlling factors. Cyanidiales were found to be largely diffused in the entire area, proving very successful at adapting to environmental changes. Chlamydomonas sp. and Pinnularia sp. were scattered in at least three of the five ecological stations. Some green acid-tolerant algae, such as Pseudococcomyxa simplex and Chlorella protothecoides var. acidicola, were strongly influenced by temperature and pH fluctuations and mainly limited to one station. Dunaliella acidophila is confined to a narrow area, being able to live exclusively in restricted pH and temperature ranges. In some sampling sites the peculiar chemico-physical conditions together with silica oversaturation cause the formation of a thick silica crust around cell walls. Generally, algae could act as a nucleation site for neoforming minerals, offering in some cases an ideal substrate for the formation of a thick silica crust on their surface.

Molecular markers in Viola L. subsect. Viola: Application and taxonomic implications for the identification of dubious herbarium specimens

Abstract The authors report the use of nuclear [internal transcribed spacer (ITS) sequences 1 and 2] and chloroplast DNA (trnS-trnG intergenic spacer sequences) in Viola subsect. Viola for separate tracking of maternal lineages and detecting dubious herbarium specimens. A phylogenetic investigation carried out on ITS data after removal of all material with possible hybrid origin showed that V. hirta is a monophyletic unit, whereas V. odorata includes at least V. collina and V. jaubertiana, as well as three sequences of V. alba subsp. dehnhardtii from literature. In some, among the sampled individuals, the morphological attribution to one species is contradicted by nuclear DNA, which indicated a wide distance from other non-specific individuals from different locations and closer proximity to a different species. Chloroplast DNA data for the same individuals, on the contrary concurred with morphological evidence. These findings confirm document univocal correlation between our chosen chloroplast sequences and the studied taxa at species or subspecies level; these sequences have the appropriate variability range to be employed for detection of the maternal lineage of unknown Viola samples.

Analysis of the genus Petagnaea Caruel (Apiaceae), using new molecular and literature data

In Southern Italy, an endemic monotypic genus belonging to family Apiaceae occurs: Petagnaea (P. gussonei), relict of Tertiary flora, belonging to subfamily Saniculoideae. At present, P. gussonei is an endangered species and is included in various lists of species deserving special protection. The genus belongs to scapose hemicryptophytes and shares a sciaphilous habitat (hygrophilous woodland). This study is aimed at doing a complete contribution about the evolutionary history of Petagnaea, using molecular markers as plastidial DNA (cpDNA), nuclear ribosomal DNA (rDNA) and data present in literature. We used nucleotide sequences from four regions of the chloroplast genome (rps16 intron, trnL(UAA) intron, atpB-rbcL intergenic spacer, and partial matK gene) to investigate possible haplotypes in Petagnaea populations. To have an idea of the molecular relationships of all populations of P. gussonei, the internal transcribed spacer (ITS) sequences, already employed in recent studies, were obtained for 18 populations. These sequences in combination with other Saniculoideae ITS sequences available from GenBank have been used for a further phylogenetic analysis. The results agree with the current classification of Saniculoideae in placing P. gussonei in tribe Saniculeae, since P. gussonei is in basal position to Sanicula. According to intraspecific chloroplast DNA diversity, no different haplotypes were detected. In addition to molecular data, morphology, cytology, phytochemistry and conservation status have been considered in the discussion.

Pinnularia obscura Krasske (Bacillariophyceae, Bacillariophyta) from acidic environments : characterization and comparison with other acid-tolerant Pinnularia species

The genus Pinnularia Ehr. (Bacillariophyceae, Bacillariophyta) is very frequently found in algal communities of acidic environments. Several Pinnularia strains isolated from the thermal acidic area of Pisciarelli (Naples, Italy) have been investigated by using a combination of morphological, ecophysiological and molecular techniques and have been compared with 15 Pinnularia strains from acidic and neutral environments, obtained from Loras College Freshwater Algal Collection. Electron microscopy (EM) observations showed the presence of a single Pinnularia species in Italian isolates, Pinnularia obscura. The complete identity between the strains of P. obscura isolated from the thermo acidic hydrosystem of Pisciarelli and from freshwater environments revealed the ability of this species to disperse throughout the globe, colonizing both acidic and neutral habitats. Overall, the genus Pinnularia has been confirmed to show a very weak morphological variation between species; in fact, the main morphological traits helpful to discriminate among them have been identified only by EM. Low pH values were tolerated by the majority of Pinnularia strains and species, both from acidic and neutral environments. As shown by a 18S rDNA phylogenetic analysis, acid-tolerance within Pinnularia is homoplasious, as a reversion from intolerance to tolerance is documented at least in P. gentilis.

Diversity of phototrophic components in biofilms from Piperno historical stoneworks

We investigated phototrophic microorganisms dwelling on stone walls made of Piperno, a volcanic rock frequently used as construction material in historical buildings in Naples, Italy. Biofilms from three historical buildings in the center of the city and from a natural Piperno quarry located in a suburban area were examined. Light and electron microscopy, and molecular biology techniques allowed the identification of 17 species belonging to Cyanobacteria, Rhodophyta, Bacillariophyta, and Chlorophyta. Cyanobacteria were the dominant components in all the biofilms. No significant differences in microbial composition were observed for biofilms collected in autumn and spring, with minor exceptions for the quarry samples, where environmental conditions were relatively more stable than in the city. Results are discussed in comparison with information on microbial communities dwelling on other kinds of substrata commonly used in historical buildings in the Neapolitan area.

Heterotrophic components of biofilms on wood artefacts

Heterotrophic components of biofilms on wood artefacts were studied at the Conservation Laboratory for Wood Artefacts of the University Suor Orsola Benincasa of Naples, Italy. The aim of the study was to add new information on the micro-habitats represented by biofilms formed by wood-dwelling organisms. Light and electron microscopy of histological features of woods used to make the artefacts showed that the woods belonged to species of lime (Tilia sp.), poplar (Populus sp.) and pear (Pyrus sp.). A Denaturing Gradient Gel Electrophoresis analysis performed on heterotrophic microorganisms colonizing the artefacts led to identify four species of bacteria, namely Bacillus cereus, B. mycoides, B. subtilis and Microbacterium oleivorans, and seven species of fungi, namely Alternaria alternata, Aspergillus fumigans, A. versicolor, Cladosporium cladosporioides, C. oxysporum, Fusarium oxysporum and Penicillium chrysogenum. Based on its morphological features, an insect found on some artefacts was identified as the xylophagous beetle Nicobium castaneum (Anobiidae). The influence of wood type and environmental conditions on the diversity of microorganisms was discussed.

Population genetics analysis in a relic population of silver fir (Abies alba Mill.) in southern Italy: A comparison with microsatellites and reference data

Abstract We investigated the genetic diversity of the last natural population of Abies alba Mill. in Campania region (southern Italy) using nuclear and chloroplast microsatellite markers. We found high genetic diversity despite small population size and geographic isolation, especially when comparing our microsatellite data with information from the literature.