Determination of carboxylic acids in vinegars and in Aceto Balsamico Tradizionale di Modena by HPLC and GC methods

The presence of carboxylic acids in grape products has been investigated for a long time by researchers, from both the qualitative and quantitative points of view. Evaluation of carboxylic acids requires the study and optimization of some operative variables which are strictly related to the matrix. In particular, the determination of organic acids in real matrixes such as Aceto Balsamico Tradizionale of Modena (ABTM; a traditional balsamic vinegar made from cooked grape must) is often difficult because of the presence of numerous interferences that need to be removed by separation techniques. To this aim, in the present work a solid-phase extraction (SPE) method with C18 and NH(2) exchangers was used to clean the ABTM samples prior to analysis or further treatments. Both HPLC and GC techniques were used to determine organic acids. The efficiency of these two different analytical techniques in the study of ABTM acidic composition has been evaluated. Both methods separately were not able to supply all the data related to carboxylic acids. In particular, HPLC allows acetic and lactic acids quantification, but gluconic and succinic acids are better determined by GC. As far as tartaric, citric, and malic acids are concerned, both HPLC and GC methods give statistically equivalent results. The variation of the single acidic species composition along a series of casks furnished interesting information regarding the chemical transformations taking place during the aging process of this product.     

Subunit composition of proteins from seeds of Lupinus albus

All the main globulins in the seeds ofLupinus Albus are oligomeric glycoproteins. Legumins (33%) consist of two similar protein molecules which contain protomers linked by disulphide bridges. They result from a partial proteolytic breakdown of an original polypeptide chain. Vicilins (44%) consist of four similar protein molecules with several protomers linked together by non-covalent bonds. Globulin 1 (6%) has a native M.W. of 199 kd and is formed by four 45.0 kd subunits consisting of two smaller protomers (28.0 and 16.0 kd) linked by -S-S- bonds. Globulin 9b (12.5%) has the lowest M.W. (44.0 kd) and is made up of three protomers, two of which are linked by disulphide bonds.     

Avian mycobacteriosis in companion birds: 20-year survey

The causative agents of avian mycobacteriosis in pet birds are rarely identified. The aim of this study is to add information about the etiology of avian mycobacteriosis. The identification of mycobacterium species in 27 cases of avian mycobacteriosis in pet birds was investigated by polymerase chain reaction (PCR) and sequencing of a rRNA hypervariable region. Avian mycobacteriosis appeared to be an infrequent diagnosis. Interestingly, a few cases of avian mycobacteriosis were recorded in very young birds. The most commonly affected species were the canary (Serinus canarius), the Eurasian goldfinch (Carduelis carduelis) and the red siskin (Spinus cucullatus). All but one bird were infected with Mycobacterium genavense. Mycobacterium avium was identified only in one case.     

Genetic transformation of Eustoma grandiflorum Griseb. by microprojectile bombardment

Summary Foreign DNA was introduced into cell suspension cultures and leaf tissue of Eustoma grandiflorum Griseb. (lisianthus) by microprojectile bombardment. For this purpose a low-cost bombardment device that uses a helium flux to accelerate microprojectiles was built. When cell suspensions were used, an average of 4.1 Kan resistant calli were recovered per shot after 4 months' cultivation on selective medium. Most of the Kan resistant plants regenerated from calli were positive to GUS assay. Both the nptII and gus genes were successfully amplified from alkali-treated leaves of putative transgenic plants by PCR analysis. Transgenic plants were not recovered from bombarded leaves. Considering the host range specificity of Agrobacterium, and the response of the species to plant regeneration from suspension culture, microprojectile bombardment is, at present, the most efficient procedure for genetic transformation of lisianthus.Abbreviations BA 6-benzyladenine - Cx cefotaxime - 2,4 D (2,4-dichlorophenoxy) acetic acid - FDA fluorescein diacetate - gus -glucuronidase - IAA indole-3-acetic acid - IBA indole-3-butyric acid - 2iP (2-isopentenyl) adenine - Kan kanamycin - nptII neomycin phosphotransferase II - PCR polymerase chain reaction     

Quinolizidine alkaloids in seeds of lupin genotypes of different origins

The intake of lupin-based foods could imply the exposure of consumers to quinolizidine alkaloids. The objectives of this study were to assess the genetic variation among and within 11 geographic regions of Lupinus albus ecotypes, verify the quinolizidine alkaloids amount of alkaloid-poor L. albus and Lupinus angustifolius varieties, and assess the effect of two climatically contrasting Italian environments on the alkaloid content. The quantitation was performed by GC-MS, and in all samples lupanine was the most abundant quinolizidine alkaloid, followed by albine and 13alpha-hydroxylupanine for L. albus and by 13alpha-hydroxylupanine and angustifoline for L. angustifolius. Some regions tended to have a high (Azores) or low (Egypt, Near East, Maghreb) total alkaloids content, but the variation among ecotypes within regions was larger than that among regions following the estimation of variance components. Alkaloid-poor varieties tended to have higher total alkaloid contents when grown in the subcontinental climate site, exceeding in some cases the limit of 0.200 mg/g.     

A spatial dataset of forest mensuration collected in black pine plantations in central Italy

Key message

The dataset provides an exhaustive tree inventory with forest mensuration and spatial location carried out in 54 plots sampled in 45- to 55-year-old black pine plantations, located in two areas of Tuscany (central Italy). Forest mensuration includes horizontal and vertical structure measurements and a total of 4171 trees were geo-referenced. The most abundant species was the black pine, Pinus nigra spp. laricio , for which a total of 3631 trees were observed. The dataset was collected as part of the SelPiBio LIFE project (LIFE13 BIO/IT/000282). Dataset access at   http://doi.org/10.5281/zenodo.438681 . Associated metadata available at https://metadata-afs.nancy.inra.fr/geonetwork/apps/georchestra/?uuid=73591027-0f1e-40a3-95d0-b614517c1290&hl=eng .

Context

The main aim of the SelPiBio LIFE project (www.selpibio.eu) is to demonstrate the effects of two thinning regimes, selective and from below, on soil biodiversity in young black pine stands. The spatial structure of forests and the relationships between trees are a good proxy of overall biodiversity level. Spatial datasets with geo referenced trees and related mensurational data represent the highest level of information for forest inventories and research activities.

Aims

This dataset has been developed during the A2 Action (Assessment of structural and mensurational parameters of the forest stands and the dead wood) of the project, to record the main mensurational parameters of the studied black pine stands. A tree-level database was compiled to describe the vertical and horizontal structure of 54 monitoring plots before the application of the silvicultural treatment.

Methods

In addition to classical in-field measurements (e.g. diameters at breast height, total height of the tree, crown depth etc.), all trees were georeferenced by means of polar coordinates collected from the centre of each monitoring plot, including crown projection on the ground, described with eight points. Then, a polynomial spline function was fitted across the recorded data to obtain a convex polygon and to calculate crown area and crown perimeter of each measured tree in GIS environment.

Results

A polygonal ESRI shapefile in ETRS89/UTM32N reference system (EPSG: 25832) with 4171 records representing the crown projections on the ground of each measured tree with all the mensurational parameters included into the attribute table. The database is freely available under the Creative Commons Attribution-NonCommercial 4. 182 0 License.

Conclusion

With this database, a wide range of forestry-related indices could be easily calculated, including geostatistical analysis and autocorrelation functions, to compare Italian artificial black pine stands with other studied forests.

     

Effects of forest management on the amount of deadwood in Mediterranean oak ecosystems

Context

Deadwood is an important habitat for vertebrate and invertebrate species, a key factor in the nutrient cycle and a valuable carbon pool. Difference in the deadwood C stock depends on many variables such as forest type, microclimate and forest management.

Aims

We investigated the relationship between C stock in deadwood and forest management in oak stands of southern Italy.

Methods

Deadwood C stock was quantified in 74 forest stands under intensive, extensive or multifunctional management. The relationship between management and C stock in deadwood was assessed taking into account the decay class and the type of deadwood (snags, stumps and logs).

Results

Intensively managed forests are characterized by significantly lower mean levels of deadwood C than the other forms of management. Multifunctional management resulted in the highest level of C, mainly in logs and snags, while extensive management resulted in high levels of C storage concentrated in snags.

Conclusion

Results of the research highlight that forest management practices greatly influence the quantitative and qualitative presence of deadwood in forests.     

From inventory to consumer biomass availability—the ITOC model

Key message The application of the ITOC model allows the estimation of available biomass potentials from forests on the basis of National Forest Inventory data. The adaptation of the model to country-specific situations gives the possibility to further enhance the model calculations.

Context

With the rising demand for energy from renewable sources, up-to-date information about the available amount of biomass on a sustainable basis coming from forests became of interest to a wide group of stakeholders. The complexity of answering the question about amounts of biomass potentials from forests thereby increases from the regional to the European level.

Aims

The described ITOC model aims at providing a tool to develop a comparable data basis for the actual biomass potentials for consumption.

Methods

The ITOC model uses a harmonized net annual increment from the National Forest Inventories as a default value for the potential harvestable volume of timber. The model then calculates the total theoretical potential of biomass resources from forests. By accounting for harvesting restrictions and losses, the theoretical potential of biomass resources from forests is reduced and the actual biomass potentials for consumption estimated.

Results

The results from ITOC model calculations account for the difference between the amounts of wood measured in the forests and the actual biomass potentials which might be available for consumption under the model assumptions.

Conclusion

The gap between forest resource assessments and biomass potentials which are available for consumption can be addressed by using the ITOC model calculation results.

     

Tree rings indicate different drought resistance of a native (Abies alba Mill.) and a nonnative (Picea abies (L.) Karst.) species co-occurring at a dry site in Southern Italy

Climate changes induced by the anthropogenic alteration of the atmospheric radiative balance are expected to change the productivity and composition of forest ecosystems. In Europe, the Mediterranean is considered one of the most vulnerable regions according to climatic forecasts and simulations. However, although modifications in the inter-specific competition are envisaged, we still lack a clear understanding of the ability of the Mediterranean vegetation to adapt to climate changes. We investigated how two co-occurring tree species commonly used in afforestation programmes, the native Abies alba Mill. and the nonnative Picea abies L. Karst., adapt to climate change by assessing their growth performance and physiological responses in relation to past climate variability. Growth was addressed by analysing tree-ring width and carbon and oxygen stable isotopes. Statistical relationships between isotopic value and monthly climate data suggest that the two species underwent ecophysiological adaptation to Mediterranean climatic constraints. These adaptations are also expressed in the ring-width data. Based on the carbon isotope ratio reflecting the stomatal response to drought, we found that the precipitation in the first period of the growing season, i.e. early spring, is a major factor influencing the annual growth of A. alba, which although native, proved to be sensitive to drought. P. abies, on the other hand, showed a higher tolerance to summer drought stress. These findings should help define criteria for sustainability and effective forest conservation in the Mediterranean region.