Occurrence of potentially pathogenic Vibrio in oysters (Crassostrea gigas) and waters from bivalve mollusk cultivations in the South Bay of Santa Catarina

Introduction This research aimed to identify and quantify potentially pathogenic Vibrio from different cultivations of bivalve shellfish in the State of Santa Catarina, Brazil, and water regions in the South Bay, as well as correlate the incidence of these microorganisms with the physicochemical parameters of marine waters. Methods Between October 2008 and March 2009, 60 oyster and seawater samples were collected from six regions of bivalve mollusk cultivation, and these samples were submitted for Vibrio counts. Results Twenty-nine (48.3%) oyster samples were revealed to be contaminated with one or more Vibrio species. The Vibrio parahaemolyticus and Vibrio vulnificus counts in the samples ranged from < 0.5 log10 Most Probable Number (MPN) g–1 to 2.3 log10 MPN g–1 oyster and from < 0.5 log10 MPN g–1 to 2.1 log10 MPN g–1 oyster, respectively. Of the 60 seawater samples analyzed, 44 (73.3%) showed signs of contamination with one or more vibrio species. The counts of V. parahaemolyticus and V. vulnificus in the samples ranged from < 0.3 log10 MPN·100mL–1 to 1.7 log10MPN·100mL–1 seawater and from < 0.3 log10 MPN·100mL–1 to 2.0 log10 MPN·100mL–1 seawater, respectively. A positive correlation between V. vulnificus counts and the seawater temperature as well as a negative correlation between the V. parahaemolyticus counts and salinity were observed. Conclusions The results suggest the need to implement strategies to prevent vibrio diseases from being transmitted by the consumption of contaminated bivalve shellfish.

A novel metabolite from the Chilean mollusk Siphonaria lessoni

A new and two previously known metabolites possessing a polypropionate carbon skeleton have been isolated from the marine gastropod mollusk Siphonaria lessoni, collected at Chilean coasts. Their structures have been determined by spectroscopical methods.

Antiviral activity of the green marine alga Ulva fasciata on the replication of human metapneumovirus

We evaluated the antiviral activity of the marine alga, Ulva fasciata, collected from Rasa beach and Forno beach, Búzios, Rio de Janeiro, Brazil on the replication of human metapneumovirus (HMPV). The algae extracts were prepared using three different methodologies to compare the activity of different groups of chemical composites obtained through these different methodologies. Four out of the six extracts inhibited nearly 100% of viral replication. The results demonstrated that the majority of the extracts (five out of six) possess virucidal activity and therefore have the ability to interact with the extracellular viral particles and prevent the infection. On the other hand, only two extracts (from Forno beach, obtained by maceration and maceration of the decoction) were able to interact with cell receptors, hindering the viral entry. Finally, only the extract of algae collected at Forno beach, obtained by maceration presented intracellular activity. To our knowledge, this is a pioneer study on antiviral activity of marine algae against HMPV. It is also the first on antiviral activity against HMPV ever done in Brazil. The study also shows the effect of different environment factors and different chemical procedures used to obtain the extract on its biological properties.

MOLLUSCICIDAL AND LARVICIDAL ACTIVITIES OF Atriplex inflata AERIAL PARTS AGAINST THE MOLLUSK Galba truncatula, INTERMEDIATE HOST OF Fasciola hepatica

Fasciolosis is a widespread parasitosis of farm live-stock in many developing countries. For this reason, it is necessary to search for new substances against parasitic diseases caused by flukes. Indeed, a wide variety of terrestrial plants have been subjected to chemical and pharmacological screening in order to discover their potential for human medicinal use. The molluscicidal and larvicidal activities of Atriplex inflata were tested on Galba truncatula and Fasciola hepatica larval stages infecting this snail in Tunisia. Phytochemical tests were conducted on extracts in order to establish a meaningful relationship with molluscicidal and larvicidal activities. The molluscicidal activity was evaluated by subjecting snails to sample aqueous solutions. Accordingly, hexane, ethyl acetate, methanol and methanol-water (8:2, v-v) were used as extraction solvents. As a result, hexane and ethyl acetate extracts showed potent activity, according to the World Health Organization, giving LC50 = 7.59 mg/L and 6.69 mg/L for hexane extracts of leaves and fruits, respectively. Ethyl acetate extracts gave LC50 = 5.90 mg/L and 7.32 mg/L for leaves and fruits, successively. Molluscicidal activities of powders were less potent on snails, but active according to the World Health Organization. Hexane and ethyl acetate extracts from leaves and fruits gave potent larvicidal activities with a delay rate exceeding 45.50% (45.50- 98.92%). Phytochemical tests showed that these activities may be attributed to the presence of triterpenoids and/or sterols.

Contribution to the marine propeller hydrodynamic design for small boats in the Amazon region

ABSTRACTIn the Amazon, river navigation is very important due to the length of navigable rivers and the lack of alternative road networks. Boats usually operate in unfavorable conditions, since there is no hydrodynamic relation among propellers, geometry, and the dimensions of the boat hull. Currently, there is no methodology for propeller hydrodynamic optimization with low computational cost and easy implementation in the region. The aim of this work was to develop a mathematical approach for marine propeller design applied to boats typically found on Amazon rivers. We developed an optimized formulation for the chord and pitch angle distributions, taking into account the classical model of Glauert. A theoretical analysis for the thrust and torque relationships on an annular control volume was performed. The mathematical model used was based on the Blade Element Momentum Theory (BEMT). We concluded that the new methodology proposed in this work demonstrates a good physical behavior when compared with the theory of Glauert and the experimental data of the Wageningen B3-50 propeller.

A new recent marine Ostracoda species (Hemicytheridae) from Brazil

Ostracods were collected on Sargassum sp. from the littoral of São Sebastião, São Paulo State, southeastern Brazil. A new species, Aurila ornellasae, is illustrated and described based on a population with various instars and adult specimens. This is the first living species of this genus described from Brazil. A brief discussion on the systematics of the genus Aurila Pokorný, 1955 and its allied genera is presented.

Quantitative fidelity of recent freshwater mollusk assemblages from the Touro Passo River, Rio Grande do Sul, Brazil

This study represents one of the first contributions to the knowledge on the quantitative fidelity of the recent freshwater molluscan assemblages in subtropical rivers. Thanatocoenoses and biocoenoses were studied in straight and meandering to braided sectors, in the middle course of the Touro Passo River, a fourth-order tributary of the Uruguay River, located in the westernmost part of the State of Rio Grande do Sul. Samplings were carried out through quadrats of 5 m², five in each sector. A total area of 50 m² was sampled. Samplings were also made in a lentic environment (abandoned meander), with intermittent communication with the Touro Passo River, aiming to record out-of-habitat shell transportation from the lentic communities to the main river channel. The results show that, despite the frequent oscillation of the water level, the biocoenosis of the Touro Passo River shows high ecological fidelity and undergoes little influence from the lentic vicinal environments. The taxonomic composition and some features of the structure of communities, especially the dominant species, also reflect some ecological differences between the two main sectors sampled, such as the complexity of habitats in the meandering-sector. Regarding the quantitative fidelity, 60% of the species found alive were also found dead and 47.3% of the species found dead were also found alive, at river-scale. However, 72% of the dead individuals belong to species also found alive. This value might be related with the good rank order correlation obtained for live/dead assemblages. Consequently, the dominant species of the thanatocoenoses could be used to infer the ecological attributes of the biocoenoses. The values of all the indexes analyzed were very variable in small-scale samplings (quadrat), but were more similar to others registered in previous studies, when they were analyzed in a station and river scale.

Report of Lepocreadium Bimarium manter, 1940, Vitellibaculum Spinosa (Siddioi) & Cable, 1960) and Hirudinella Ventricosa (Pallas, 1774), parasites of marine fishes in Brazil

Lepocreadium bimarinum and Vitellibaculum spinosa are referred for the first time in Stephanolepis hispidus and in Brazil, and Hirudinella ventricosa is reported from Scomberomorus cavalla. Measurements, figures and comments are given.

Dinosoma clupeola sp. n. (Hemiuridae) and Pseudoacanthostomum floridensis Nahhas & Short, 1965 (Acanthostomidae), digenetic trematodes in Brazilian Marine fishes

Dinosoma clupeola sp. n. is described from Harengula clupeola, and resembles D. hawaiiense Yamaguti, 1970, from which it differs in the entire, elongate-saccular seminal vesicle, tegument weakly plicated, smaller size of body and internal organs, and slightly larger and narrower eggs. Pseudoacanthostomum floridensis Nahhas & Short, 1965 is referred to Netuma barba, which represents a new host record.

Schikhobalotrema solitaria sp. n. and S. acanthuri Yamaguti, 1970 (Haplosplanchnidae: Digenea) in Brazilian marine fishes

Schikhobalotrema solitaria sp. n. is described from Stephanolepis hispidus (Linnaeus, 1758), and is characterized by the relation between oral sucker and pharynx 1:1,1. This Relation in the other species ranges between 1:0.3-0.6. It is more similar to S. manteri Siddiqi & Cable, 1960 in the distribution of vitellaria, differing from it in the size of vitelline follicles, extension of uterus and in the size of the eggs. S. acanthuri Yamaguti, 1970 is referred for the first time in South America in Mugil liza Valenciennes, 1836 representing a new host record.

Some monogenoidea parasitic on peruvian marine fishes, with description of Anoplocotyloides chorrillensis new species and new records

The presence of four Monogenoidea parasitic on marine fishes from the central Peruvian coast is recorded. One of them, Anoplocotyloides chorrillensis (Monocotylidae) described from the gills of Rhinobatos planiceps (Rhinobatidae) is considered a new species. The three other species are: Caballerocotyla autralis Oliva, 1986 (Capsalidae); Callorhynchocotyle marplatensis Suriano & Incorvaia, 1982 (Hexabothriidae) and Anoplocotyloides papillatus (Doran, 1953) (Monocotylidae) parasitic on Sarda chiliensis chiliensis (Scombridae), Callorhinchus callorhinchus (Callorhinchidae) and Rhinobatos planiceps (Rhinobatidae) respectively.

Marine organisms: an alternative source of potentially valuable natural products

This paper recalls the outcoming of marine natural products research and reviews a selection of marirne bioactive metabolites in current use together with promising trends in marine pharmacology.

First report of the genera Macvicaria Gibson & Bray, 1982, Pachycreadium Manter, 1954 and Saturnius manter, 1969 (Trematoda: Digenea), in brazilian marine fishes

Macvicaria crassigula (Linton, 1910) (Opecoelidae) is referred from the intestine of Micropogonias furnieri and from Stellifer rastrifer; and from Stellifer rastrifer, and Saturnius maurepasi Overstreet, 1977 (Bunocotylidae) from the stomach of Mugil liza. This is the first report of these species in Brazil, and a new host records are presented.

New host records and localities of some Monogenea from brazilian marine fishes with scanning electron microscopy of Bicotylophora trachinoti (Mac Callum, 1921)

Bicotylophora trachinoti (Mac Callum, 1921) from Trachinotus carolinus L.; Pseudanthocotyloides heterocotyle (Van Beneden, 1871) from Cetengraulis edentulus (Cuvier), and Decapterus punctatus (Cuvier), new host records; Pseudomazocraes selene Hargis, 1957 from Selene vomer (L.) and Caranx latus Agassiz, new host record, are reported for the first time in Brazil from the coast of Rio de Janeiro State. The marine fishes Diplectrum sp. and Pomatomus saltatrix (L.) are respectively new host records for Pseudotagia cupida (Hargis, 1956) and Macrovalvitrema sinaloense Caballero & Bravo Hollis, 1955. Measurements, original figures and photos in scanning electron microscopy of B. trachinoti are presented. The egg with filaments is reffered for the first time in the genus Pseudanthocotyloides.