Vernonia polyanthes as a new source of antiulcer drugs

Methanolic (VPME) and chloroformic (VPCL) extracts, obtained from the aerial parts of Vernonia polyanthes, were investigated for its antiulcerogenic properties. Administration of VPME (250 mg/kg) and VPCL (50 mg/kg) significantly inhibited the gastric mucosa damage (64% and 90%, respectively) caused by absolute ethanol (p.o.). Otherwise, in NSAID-induced gastric damage, their gastroprotective effects have decreased. Since the VPCL extract resulted to be more effective than the VPME we focused our efforts over VPCL action mechanism of action.     

Aluminum stress stimulates the accumulation of organic acids in root apices of Brachiaria species

Aluminum‐resistant Brachiaria decumbens Stapf cv. Basilisk (signalgrass) and closely related, but less resistant Brachiaria ruziziensis Germain & Evrard cv. Common (ruzigrass) both accumulated high concentrations of aluminum (Al) in roots. Approximately two thirds of the total Al was complexed by soluble low‐molecular‐weight ligands, suggesting that it had been taken up into the symplasm. We therefore investigated whether these species might employ Al‐chelating organic acids for internal detoxification of Al taken up by root apices, the primary site of Al injury. Unlike root apices of other Al‐resistant plant genotypes, which secrete organic‐acid anions to detoxify Al externally, apices of Brachiaria species accumulated organic acids within the tissue. A comparison with whole roots showed that this preference for accumulation (as opposed to secretion) was restricted to apices. Citric acid, and to a lesser extent trans‐aconitic acid, accumulated in a uniform dose‐dependent manner in root apices of both species as their Al content increased under Al‐toxic growth conditions. Their accumulation was accompanied by a stimulation of malate synthesis in Al‐resistant B. decumbens, while it occurred at the expense of malate in Al‐sensitive B. ruziziensis. These data suggest a role of organic acids in the internal detoxification of Al in root apices of both Brachiaria species, presumably contributing to their comparatively high basal level of Al resistance. Yet internal detoxification of Al by organic acids does not appear to be the principal mechanism responsible for the superior resistance of B. decumbens.     

The Structure of the Lipid A of Gram-Negative Cold-Adapted Bacteria Isolated from Antarctic Environments

Gram-negative Antarctic bacteria adopt survival strategies to live and proliferate in an extremely cold environment. Unusual chemical modifications of the lipopolysaccharide (LPS) and the main component of their outer membrane are among the tricks adopted to allow the maintenance of an optimum membrane fluidity even at particularly low temperatures. In particular, the LPS’ glycolipid moiety, the lipid A, typically undergoes several structural modifications comprising desaturation of the acyl chains, reduction in their length and increase in their branching. The investigation of the structure of the lipid A from cold-adapted bacteria is, therefore, crucial to understand the mechanisms underlying the cold adaptation phenomenon. Here we describe the structural elucidation of the highly heterogenous lipid A from three psychrophiles isolated from Terra Nova Bay, Antarctica. All the lipid A structures have been determined by merging data that was attained from the compositional analysis with information from a matrix-assisted laser desorption ionization (MALDI) time of flight (TOF) mass spectrometry (MS) and MS² investigation. As lipid A is also involved in a structure-dependent elicitation of innate immune response in mammals, the structural characterization of lipid A from such extremophile bacteria is also of great interest from the perspective of drug synthesis and development inspired by natural sources.     

Geographical Patterns of Variation in Bari Faba Bean Germplasm Collection

A large collection of great interest and usefulness for faba bean breeding has been assembled at the Bari Germplasm Institute. Our objective was to describe the phenotypic diversity of a large sample (1565 entries from 39 countries) of this collection. Entries were characterized for 10 discontinuous traits to determine variation within and among geographical regions. Phenotypic variation was found within all regions for most traits. The Shannon-Weaver diversity index varied widely across regions, but was relatively even for most traits scored. Canonical discriminant analysis and clustering of the canonical means conducted separately for each botanical type, revealed useful phenotypic groupings of origin for future faba bean germplasm management. Based on the diversity and number of entries, East Europe, South-East Asia and North America seem under represented in the collection while South America is not represented at all. Information presented in this study could be used to devise a core collection, which would contain much of the diversity found in the Bari collection.     

Analyses of genetic diversity in Cuban rice varieties using isozyme, RAPD and AFLP markers

A survey of the genetic diversity among the major cuban rice cultivars was conducted using isozyme, RAPD and AFLP markers. Polymorphisms were detected for esterases, peroxidases, alcohol dehydrogenases and polyphenoloxidases systems; 21 RAPD primers and four AFLP primer combinations. Heterozygosity arithmetic mean value (H_av(p)), the effective multiplex ratio (EMR) and the marker index (MI), were calculated for isozyme, RAPD and AFLP markers. The mean value of genetic similarity among the different varieties was 0.92 for isozyme, 0.73 for RAPD and 0.58 for AFLP analyses. Thus, AFLP were able to detect polymorphisms with higher efficiency than RAPD (+15%) and isozyme (+34%). Data from the isozyme, RAPD and AFLP analyses were used to compute matrices of genetic similarities. The efficiency of the UPGMA for the estimation of genetic relatedness among varieties was supported by cophenetic correlation coefficients. The resulting values indicated that the distortion level for the estimated similarities was minimal. The correlation coefficients obtained by the Mantel matrix correspondence test, which was used to compare the cophenetic matrices for the different markers, showed that estimated values of genetic relationship given for isozyme and RAPD markers (r = 0.89), as well as for AFLP and RAPD markers (r = 0.82) were properly related. However, AFLP and isozyme data showed only moderate correlation (r = 0.63). Although the genetic variability found among the different cultivars was low, both RAPD and AFLP markers proved to be efficient tools in assessing the genetic diversity of rice genotypes. This revised version was published online in July 2006 with corrections to the Cover Date.     

SSR-based identification key of cultivars of Olea europaea L. diffused in Southern-Italy

Olive (Olea europaea L.) is an important fruit species in Italy and Mediterranean basin constituted by a wide germplasm with a large number of cultivars present in all the Mediterranean area. SSRs are becoming the markers of choice for variability studies in olives as they are simple to perform, transferable, hypervariable, highly polymorphic and show a high information content.Olive genetic diversity was studied using 16 SSR markers on 30 cultivars diffused in Southern-Italy. Resolving Power (RP) and Power of Discrimination (PD) were calculated to evaluate the efficiency of the SSR markers investigated in studies of cultivars fingerprinting. Based on their high efficiency, two SSR markers, UDO43 and DCA16 were chosen to set up an identification key to distinguish the entire set of cultivars, confirming the high biodiversity of the Southern-Italian olive germplasm and the suitability of SSR markers in studies of cultivar diagnosis.     

Immunophenotypic evaluation of working Labrador Retrievers and German Shepherd dogs living in the same environment

Multiparametric flow cytometry was used to compare peripheral blood lymphocyte subset distribution between healthy working police Labrador Retrievers (LRs; n=12) and German Shepherd dogs (GS; n=11) living in the same environment. The CD4/CD8 ratio was significantly higher in LR than in GS because of the lower percentage of CD8+ T lymphocytes in LR. GS showed the highest relative percentage of CD3-/CD21- lymphocytes, whereas LR had the highest percentages of MHC II+ lymphocytes. Because age, sex, environmental and housing conditions, dietary patterns, and training or working routines were similar in both breeds in the study, differences in peripheral blood lymphocyte subset distribution could be attributed to the influence of breed on the immune system.     

Fractionation of chromium in tannery sludge-amended soil and its availability to fenugreek plants

Purpose

Fenugreek (Trigonella foenum-graecum L.) is a medicinal plant with antidiabetic effects. Chromium has been related to better glucose tolerance in humans. The objective of this study was to determine whether tannery sludge could be used for Cr biofortification of fenugreek.

Materials and methods

Soil was mixed with tannery sludge containing 6.03 g Cr kg^?1. All Cr was in the form of Cr(III). Three treatments were disposed: control without sludge, and two treatments with 10 and 20 g sludge kg^?1, respectively. Control and the 10 g sludge kg^?1 treatments received NPK fertilizer to adjust the concentrations of major mineral nutrients to similar levels in all treatments. Soils were potted and planted with fenugreek. Plants harvested at the initial flowering stage were analysed for total Cr, Fe, Zn and Pb. Sequential soil extraction was applied to obtain operationally defined soil Cr fractions.

Results and discussion

Total Cr in all treatments was below or within the allowable range for agricultural soils (100–150 mg kg^?1). In control soils, most Cr was in the residual fraction (HF/HClO₄ digest). Tannery sludge-amended soils incorporated most Cr into the moderately reducible fraction (oxalic acid/ammonium oxalate extract). In fenugreek shoots, Cr concentrations reached 3.2 mg Cr kg^?1, a higher concentration than that reported for other leafy vegetables. Lead concentrations in plant shoots from this treatment were enhanced but hardly exceeded 1 mg Pb kg^?1.

Conclusions

Tannery sludge-amended soils containing Cr within the range of permissible concentrations can increase shoot Cr in fenugreek. Only sludge with low Pb concentrations should be used for Cr biofortification of fenugreek.     

Adsorption and desorption of dimepiperate by soils

The adsorption and desorption of dimepiperate, S-(,-dimethylbenzyl)-1-piperidinecarbothioate, on three soils of various physical and chemical properties was studied. Adsorption isotherms conformed to Freundlich equation. The k _f values increased with increasing organic carbon content of the soils. To confirm the effect of organic matter, the adsorption of the herbicide was studied after removal of organic matter by peroxidation. This soil treatment caused a sequential loss of adsorptive capacity. Desorption isotherms also conformed to Freundlich equation, but K _des values were higher than those for adsorption and increased with increase in concentration of initially adsorbed dimepiperate. Hysteresis was indicated by the decrease in slope of desorption compared to adsorption isotherms. Hysteresis decreased with increasing methanol content in the extracting solution. The factors involved are discussed.