Inhibition of Vancomycin and High-Level Aminoglycoside-Resistant Enterococci Strains and Listeria monocytogenes by Bacteriocin-Like Substance Produced by Enterococcus faecium E86

Three hundred and thirty nine lactic bacteria strains isolated from food samples were screened for antimicrobial activity. Only one strain isolated from meat pie and identified as Enterococcus faecium produced a bacteriocin-like inhibitory substance (BLIS) showing activity against Enterococcus, Leuconostoc, Lactobacillus, Listeria, Corynebacterium and Staphylococcus aureus. The BLIS produced was resistant to acid and alkali treatment and 121oC for 15 min. The addition of BLIS in BHI contaminated with Listeria monocytogenes decreased the contamination in 4.8 log cycles in 24 h. The inhibition of listeria was also obtained in milk. Forty multiresistant enterococci strains were inhibited in the well-diffusion test. Two vancomycin resistant strains tested in liquid with BLIS were also inhibited. The BLIS producer showed no pathogenicity marker.     

Leaching of petroleum refinery ash by acidophilic sulfur-oxidizing microbial cultures

Sulfur-oxidising acidophilic bacteria were obtained from weathered sulfur piles produced by a petroleum refinery. When grown on commercial sulfur the yield was 10(10)cell/g S. Sulfur conversion to sulfate was about 95% after 17 days. Cultures were also grown together with ash obtained from incinerated refinery sludge, which contained high amounts of iron. Cultures grown in ash plus sulfur gave somewhat higher values for the growth parameters (Y=1.6x10(10)cell/g S). The sulfur conversion was about 70% (after 17 days) and more than 90% of the iron present in the ash was also leached. The sulfur-reduced compound thiosulfate, determined using ion pair HPLC, was found in the presence and absence of ash although the profile was different in each case. Sulfite was only found in non-ash containing cultures, whereas tetrathionate was only formed in the presence of ash. These results are discussed with reference to the substrates used by the micro-organisms.     

Fishburgers with silver catfish (Rhamdia quelen) filleting residue

The utilization of filleting wastes from silver catfish in the formulation of fishburgers was evaluated by replacing grounded fish fillets with increasing levels (0-control, 20%, 50%, and 80%) of pulp obtained from filleting wastes (PFW). Fat content of burgers increased with increasing levels of PFW (p<0.05). Burgers with 50-80% PFW had lower n-6/n-3 ratio than control (p<0.05). Fat and moisture retention after cooking were not affected by PFW, while cooking yield increased in burgers with 50% PFW when compared to all other formulations (p<0.05). Texture and juiciness were not affected by PFW. However, burgers containing 80% PFW had lower overall acceptance than controls (p<0.05). Results indicated that production of fishburgers may be a valuable alternative for wastes from silver catfish filleting. Filleting wastes could substitute up to 50% of fish fillets with no changes in sensory acceptance and an improvement of nutritional value and cooking characteristics.     

Catalysts of Cu(II) and Co(II) ions adsorbed in chitosan used in transesterification of soy bean and babassu oils - a new route for biodiesel syntheses

Catalysts of Cu(II) and Co(II) adsorbed in chitosan was used in transesterification of soy bean and babassu oils. The catalysts were characterized by infrared, atomic absorption and TG, and biodiesels was characterized by infrared, NMR, CG, TG, physic chemistry analysis. The maximum adsorption values found for copper and cobalt cations were 1.584 and 1.260mgg(-1), respectively, in 180min. However, conversion of oils in biodiesel was better when used Co(II) adsorbed in chitosan.     

Optimization of extraction of high-ester pectin from passion fruit peel (Passiflora edulis flavicarpa) with citric acid by using response surface methodology

A central composite design was employed to optimize the extraction of pectin with citric acid. The independent variables were citric acid concentration (0.086–2.91% w/v) and extraction time (17–102 min). The combined effect of these variables on the degree of esterification was investigated. Results have shown that the generated regression models adequately explained the data variation and significantly represented the actual relationship between the independent variables and the responses. Besides that, the citric acid concentration was the most important factor to affect the degree of esterification, as it exerted a significant influence on the dependent variable. Lower citric acid concentration increased the pectin degree of esterification. The surface response showed the relationships between the independent variables, and thus responses were generated. Through this surface, the satisfactory condition of 0.086% w/v citric acid for 60 min was established for extraction of high-ester yellow passion fruit pectin.     

Spectroscopy and photophysics of flavin-related compounds: 3-benzyl-lumiflavin.

Molecular structure, spectroscopic and photophysical data for the singlet state of 3-benzyl-lumiflavin in different solvents are presented. Theoretical studies concerning singlet-singlet and triplet-triplet excitation energies were carried out using time-dependent density functional theory (TD-DFT) calculations. These predictions are in good agreement with the experimental results, which reflect the solvent interactions. All the observable singlet-singlet transitions have pi-pi* character. The title compound appears to be an efficient sensitizer of the production of singlet oxygen (phi(Delta)= 0.53). The crystal structure of 3-benzyl-lumiflavin is also presented, along with its solid-state photophysical data.     

Genetic diversity of peanut (Arachis hypogaea L.) and its wild relatives based on the analysis of hypervariable regions of the genome

Background  

The genus Arachis is native to a region that includes Central Brazil and neighboring countries. Little is known about the genetic variability of the Brazilian cultivated peanut (Arachis hypogaea, genome AABB) germplasm collection at the DNA level. The understanding of the genetic diversity of cultivated and wild species of peanut (Arachis spp.) is essential to develop strategies of collection, conservation and use of the germplasm in variety development. The identity of the ancestor progenitor species of cultivated peanut has also been of great interest. Several species have been suggested as putative AA and BB genome donors to allotetraploid A. hypogaea. Microsatellite or SSR (Simple Sequence Repeat) markers are co-dominant, multiallelic, and highly polymorphic genetic markers, appropriate for genetic diversity studies. Microsatellite markers may also, to some extent, support phylogenetic inferences. Here we report the use of a set of microsatellite markers, including newly developed ones, for phylogenetic inferences and the analysis of genetic variation of accessions of A. hypogea and its wild relatives.     

Insulin Accelerates Seedling Growth of Canavalia ensiformis (Jack bean)

Insulin is a 6 kDa peptide hormone that activates several metabolic processes and cellular growth. Germination studies showed that insulin, vanadyl sulphate (an insulin mimetic compound), tyrphostin (an inhibitor of insulin receptor kinase activity), pinitol (a chiro inositol analogue) and glucose were able to accelerate Canavalia ensiformis (Jack bean) seedling radicle and epicotyl development. Immunofluorescence microscopy analysis showed that proteins binding to insulin, insulin receptor and phosphoserine antibodies are localized in an internal layer of the C. ensiformis seed coat. These results and others previously reported from our laboratory suggest that insulin, insulin receptor and phosphoserine proteins could be components of signalling pathways akin to those present in animals.