SENSORY AND INSTRUMENTAL FLAVOR ANALYSES OF CHEESE CURD COCULTURED WITH SELECTED YEAST AND BACTERIA

Relationships between odor properties and volatile chemical composition were explored on 39 cocultures of three different yeasts, three Geotrichum candidum and five bacteria, commonly used in bacteria and mold surface ripened cheese. Sensory profiling was performed by ten trained judges by scoring the intensity of 14 odor attributes. At the same time, the volatile compounds of the cocultures were extracted and analyzed by dynamic headspace gas chromatography and mass spectrometry. Sensory and instrumental data were compared and correlated using correlation analysis and partial least squares regression analysis. The sample plot including the whole set of samples evidenced a clustering of the associations containing the yeast strain Kluyveromyces lactis and any bacteria. They developed strong fruity olfactory notes related to their high content of ethyl esters and various alcohols. The sample plot on a restricted set of samples evidenced the fruity characteristics of Debaryomyces hansenii and bacteria associations and the cheesy odors of Yarrowia lipolytica and Geotrichum candidum cocultures that produced sulfur compounds.     

The Bonobo–Dialium Positive Interactions: Seed Dispersal Mutualism

A positive interaction is any interaction between individuals of the same or different species (mutualism) that provides a benefit to both partners such as increased fitness. Here we focus on seed dispersal mutualism between an animal (bonobo, Pan paniscus) and a plant (velvet tamarind trees, Dialium spp.). In the LuiKotale rainforest southwest of Salonga National Park, Democratic Republic of Congo, seven species of the genus Dialium account for 29.3% of all trees. Dialium is thus the dominant genus in this forest. Dialium fruits make up a large proportion of the diet of a habituated bonobo community in this forest. During the 6 months of the fruiting season, more than half of the bonobos’ feeding time is devoted to Dialium fruits. Furthermore, Dialium fruits contribute a considerable proportion of sugar and protein to bonobos’ dietary intake, being among the richest fruits for these nutrients. Bonobos in turn ingest fruits with seeds that are disseminated in their feces (endozoochory) at considerable distances (average: 1.25 km after 24 hr of average transit time). Endozoochory through the gut causes loss of the cuticle protection and tegumentary dormancy, as well as an increase in size by water uptake. Thus, after gut passage, seeds are better able to germinate. We consider other primate species as a potential seed disperser and conclude that Dialium germination is dependent on passage through bonobo guts. This plant–animal interaction highlights positive effects between two major organisms of the Congo basin rainforest, and establishes the role of the bonobo as an efficient disperser of Dialium seeds. Am. J. Primatol. 75:394‐403, 2013. © 2013 Wiley Periodicals, Inc.     

A new species of Acynodon (Crocodylia) from the upper cretaceous (Santonian–Campanian) of Villaggio del Pescatore,Italy

Abstract: The new species Acynodon  adriaticus is described on the basis of remains from the Santonian–Campanian of Villaggio del Pescatore (Trieste, NE Italy). This species differs in several cranial features from Acynodon  iberoccitanus, the only other Acynodon species whose cranial osteology is known in detail. The absence of maxillary and dentary caniniform teeth coupled with the presence of enlarged molariform teeth suggests that Acynodon probably fed on slowly moving hard‐shelled prey. Moreover, the new materials reveal for the first time the morphology of some postcranial elements of Acynodon: in particular, medial‐most paravertebral osteoderms that are characterized by two keels. A new cladistic phylogenetic analysis resolves the previously reported polytomy among the basal Globidonta: Acynodon is recognized as the most primitive globidontan. This genus may represent the geologically oldest known globidontan. The fact that Acynodon has been found only in Europe and that the outgroup of Globidonta, the Diplocynodontinae, is mainly known from Europe, suggests that globidontans may have originated in Europe and not in North America as previously supposed.     

Aedes polynesiensis in the Society Islands: environmental correlates of isoenzyme differentiation

Abstract Isoenzyme genetic differentiation of Aedes polynesiensis mosquitoes in Raiatea island, French Polynesia, was evaluated by two models of population structure based on seven gene-enzyme systems: Ak, Est, Got, Gpi, Hk, Mdh and Pgm. The ecological model tested whether genetic differentiation is congruent with habitat differences. The isolation model evaluated whether genetic differentiation is proportional to geographical distribution. The ecological model found no significant differentiation between populations of Ae.polynesiensis from beach and forest ecotopes, whereas the isolation model was consistent with the data. However, incipient speciation is opposed by the source-sink system of population dynamics in such small neighbouring islands, where Ae.polynensiensis extinction is readily followed by reinvasion causing considerable gene flow between island populations.     

Genetic and Biochemical Studies on Ommochrome Genesis in an Albino Strain of a Terrestrial Isopod,Armadillidium vulgare

Genetic studies and quantitative determination of levels of 3-hydroxykynurenine and kynurenine were performed in an albino strain of a terrestrial isopod Armadillidium vulgare. From the results of matings between the albino and the albino, the red, the dark red, or the wild type individuals, the albino A. vulgare seems to be regulated by an autosomal gene(s) recessive to its wild allele. Litter mating of F₁ progenies obtained by crossing the albino and the red mutant or the albino and the dark red mutant yielded progenies at a ratio of 3:6:3:4 for the red, the dark red, the wild, and the albino phenotypes, respectively. The albino gene(s) seems not to be allelic but to be epistatic to the red gene(s) with respect to ommochrome biosynthesis. Quantitative determination of 3-hydroxykynurenine carried out by high-performance liquid chromatography with electrochemical detection revealed that the 3-hydroxykynurenine content in the albino was significantly lower than that in the wild or the red type. The whole content of 3-hydroxykynurenine after enzymatic conversion of kynurenine to 3-hydroxykynurenine was still considerably lower than that found in the wild type, even though it increased after the conversion. The albino gene(s) seems to be associated with a blockage at distinct level(s) of ommochrome biosynthesis.     

Carotenoid pigments of Dioscorea cayenensis

The yellow flesh of Dioscorea cayenensis, a principal yam of Africa, was found to contain xanthophyll esters as the principal pigments. These included neoxanthin, violaxanthin and auroxanthin. In addition β-carotene, or pro-vitamin A was found in small quantities. Measurements show that D. cayenensis is a fair source of this nutrient.