Evaluation of Antioxidant,Antibacterial and Enhancement of Antibiotic Action by Punica granatum Leaves Crude Extract and Enriched Fraction against Multidrug-Resistant Bacteria

The aim of this study was to evaluate the phytochemical composition, antioxidant, and antimicrobial potential of crude extract and fractions of Punica granatum leaves. The extract was produced by turbo extraction, after which hexanic, ethyl acetate, and aqueous fractions were obtained by partitioning. The chemical analyses were performed by thin layer chromatography and high-performance liquid chromatography, and the antioxidant activities were assayed by DPPH^. and ABTS^.+. Minimal inhibitory and bactericidal concentrations (MIC/MBC) were applied to twenty-two bacteria. Most strains susceptible to extract/fractions and resistant to antibiotics were selected, and ampicillin, azithromycin, ciprofloxacin, and gentamicin were associated with the ethyl acetate fraction (EAF) against multidrug-resistant strains in modulatory and checkboard models. The data from chromatographic analyses showed flavonoids and tannins in the extract, as well as the enrichment of EAF in phenols, mainly flavonoids. The flavonoids were connected to the electron transfer activity demonstrated in the DPPH^. and ABTS^.+ assays. Gram-positive strains are more susceptible to EAF. The subinhibitory concentrations of P. granatum enhanced the antimicrobial activity of the agents and reduced the EAF individual MIC, and the combination of EAF and antibiotics demonstrated a synergistic effect. These results present a promising approach for developing a therapy in which antioxidant extracts and fractions can be used in combination with antibiotics.     

Evolutionary profile of the family Calliphoridae,with notes on the origin of myiasis

The family Calliphoridae is a group of heterogenous calyptrate flies with a worldwide distribution including species of ecological, veterinary, medical, and forensic importance. Notorious for their parasitic habits, the larvae of many blowflies are characterised – like some other dipteran larvae – by their ability to develop in animal flesh. When parasitism affects a living host, it is termed “myiasis”. This has led the Calliphoridae to be considered as a pivotal family in its relationship with a man. Nevertheless, even after more than 50 years of research, the phylogenetic relationships among calliphorid subfamilies together with the evolutionary origin of myiasis remain unclear. In order to elucidate these problems, we constructed three phylogenetic trees by using nucleotide sequence data from cytochrome oxidase subunit one (COI), representing a mitochondrial conservative gene, and nuclear 28S subunit of ribosomal RNA gene (28S rRNA) in order to interpret the evolutionary profile of myiasis in the family Calliphoridae. The sequenced data represented species associated with ectoparasitic life-styles, either saprophagy or facultative and obligate parasitism. A total number of 50 accessions were collected for 28S rRNA, 56 for COI, and 38 for combined sequences phylogeny. Molecular Evolutionary Genetics Analysis (MEGA) software was used to align 2197 nucleotide positions of 28S rRNA and 1500 nucleotide positions of COI with a gap opening penalties and gap extension penalties equalling 20 and 0.1 respectively. The results reveal the non-monophyly of the family Calliphoridae despite the stable monophyletic status of the Chrysomyinae, Luciliinae, and Auchmeromyiinae. Also, our findings recommend ranking the Toxotarsinae as a separate family. Furthermore, comparative analysis of the phylogenetic trees shows that the habit of obligatory myiasis originated independently more than five times. This strengthens our hypothesis that the origin of eating fresh meat is a case of convergent evolution that has taken place after speciation events millions of years ago. Finally, estimating the divergence dates between lineages from molecular sequences provides a better chance of understanding their evolutionary biology.     

Comparative analysis of circulating hemocytes of the freshwater snail Pomacea canaliculata

Molluscs are invertebrates of great relevance for economy, environment and public health. The numerous studies on molluscan immunity and physiology registered an impressive variability of circulating hemocytes. This study is focused on the first characterization of the circulating hemocytes of the freshwater gastropod Pomacea canaliculata, a model for several eco-toxicological and parasitological researches.Flow cytometry analysis identified two populations of hemocytes on the basis of differences in size and internal organization. The first population contains small and agranular cells. The second one displays major size and a more articulated internal organization. Light microscopy evidenced two principal morphologies, categorized as Group I (small) and II (large) hemocytes. Group I hemocytes present the characteristics of blast-like cells, with an agranular and basophilic cytoplasm. Group I hemocytes can adhere onto a glass surface but seem unable to phagocytize heat-inactivated Escherichia coli. The majority of Group II hemocytes displays an agranular cytoplasm, while a minority presents numerous granules. Agranular cytoplasm may be basophilic or acidophilic. Granules are positive to neutral red staining and therefore acidic. Independently from their morphology, Group II hemocytes are able to adhere and to engulf heat-inactivated E. coli. Transmission electron microscopy analysis clearly distinguished between agranular and granular hemocytes and highlighted the electron dense content of the granules. After hemolymph collection, time-course analysis indicated that the Group II hemocytes are subjected to an evident dynamism with changes in the percentage of agranular and granular hemocytes. The ability of circulating hemocytes to quickly modify their morphology and stainability suggests that P. canaliculata is endowed with highly dynamic hemocyte populations able to cope with rapid environmental changes as well as fast growing pathogens.     

Citrus Allergy from Pollen to Clinical Symptoms

Allergy to citrus fruits is often associated with pollinosis and sensitization to other plants due to a phenomenon of cross-reactivity. The aims of the present study were to highlight the cross-reactivity among citrus and the major allergenic pollens/fruits, throughout clinical and molecular investigations, and to evaluate the sensitization frequency to citrus fruits in a population of children and adults with pollinosis. We found a relevant percentage of sensitisation (39%) to citrus fruits in the patients recruited and in all of them the IgE-mediated mechanism has been confirmed by the positive response to the prick-to-prick test. RT-PCR experiments showed the expression of Cit s 1, Cit s 3 and a profilin isoform, already described in apple, also in Citrus clementine pollen. Data of multiple sequence alignments demonstrated that Citrus allergens shared high percentage identity values with other clinically relevant species (i.e. Triticum aestivum, Malus domestica), confirming the possible cross-allergenicity citrus/grasses and citrus/apple. Finally, a novelty of the present work has been the expression of two phospholipaseA2 isoforms (PLA2 α and β) in Citrus as well as in Triticum pollens; being PLA2 able to generate pro-inflammatory factors, this enzyme could participate in the activation of the allergenic inflammatory cascade.     

Schisandra henryi C. B. Clarke in vitro cultures: a promising tool for the production of lignans and phenolic compounds

Plant Cell, Tissue and Organ Culture (PCTOC) - We initiated and optimized in vitro culture conditions of the endemic Chinese plant species—Schisandra henryi C. B. Clarke. Different types of...     

Field and laboratory studies on the life-cycle, growth and feeding preference in the hairy snail Trochulus hispidus (L., 1758) (Gastropoda: Pulmonata: Hygromiidae)

For the first time the life cycle of the common land snail Trochulus hispidus was completely described in Central Europe (Poland). This is a semelparous species predominantly with an annual life cycle and the reproductive period lasting from April till October. The first young snails hatch in spring, grow rapidly in summer and reach ca. 4 whorls until winter. In spring of the next year they mature and reproduce. After that they die. There is hardly any growth from late autumn till early spring. The average proportional growth rate is ca. 0.3 whorl/month in the wild. The fastest growth is present in the youngest snails and then gradually decreases over the course of their age. Laboratory and field observations allowed for establishing the following life cycle parameters: eggs calcified, almost spherical, ca. 1.5 mm, laid in spring and summer in batches of between 1 and 47. Time to hatching is 6–24 days, hatching is asynchronous; newly-hatched snails have approximately 1.5 whorls. Analysis of food preferences revealed, that T. hispidus tends to restrict its diet during the life. Generally the youngest snails equally consumed leaves of all four tree species offered (Fraxinus excelsior, Acer pseudoplatanus, Tilia cordata and A. platanoides) whereas adults preferred F. excelsior over A. pseudoplatanus and A. platanoides.     

Hundred and eighty years of fleet dynamics in the Belgian sea fisheries

Understanding the impact of fisheries on the commercial fish stocks requires detailed catch statistics and data on the dynamics of fleet and catch effort, at least before industrial fishing started. Most time-series on the fleet dynamics start after the 1980s, at times when major changes in fleet characteristics had already taken place. In the present paper, the results of the integration of data on fleet size (from 1830), tonnage (from 1842) and engine power (kW, from 1912) of the Belgian sea fisheries fleet are presented. The decrease in fleet size and changes in overall tonnage and engine power since the beginning of the reconstructed time-series, are quantified. The data show that the decrease in fleet size (?85 %) and in overall engine power (?5 %) was compensated by an increase in average tonnage per vessel (×10 increase) and in average engine power per vessel (×6 increase). The overall fishing effort of the fleet expressed as the total number of days spent at sea has decreased by approximately ?84 % between 1938 and 2010, while the average amount of fish landed per day per vessel (1,000 kg in 2008–2010) has at least doubled in the same period. The data reconstruction provides a unique view on the dynamics in the sea fisheries fleet of Belgium over 180 years and the political and social events associated to these changes.     

Biohydrogen production by dark fermentation of glycerol using Enterobacter and Citrobacter Sp

Glycerol is an attractive substrate for biohydrogen production because, in theory, it can produce 3 mol of hydrogen per mol of glycerol. Moreover, glycerol is produced in substantial amounts as a byproduct of producing biodiesel, the demand for which has increased in recent years. Therefore, hydrogen production from glycerol was studied by dark fermentation using three strains of bacteria: namely, Enterobacter spH1, Enterobacter spH2, and Citrobacter freundii H3 and a mixture thereof (1:1:1). It was found that, when an initial concentration of 20 g/L of glycerol was used, all three strains and their mixture produced substantial amounts of hydrogen ranging from 2400 to 3500 mL/L, being highest for C. freundii H3 (3547 mL/L) and Enterobacter spH1 (3506 mL/L). The main nongaseous fermentation products were ethanol and acetate, albeit in different ratios. For Enterobacter spH1, Enterobacter spH2, C. freundii H3, and the mixture (1:1:1), the ethanol yields (in mol EtOH/mol glycerol consumed) were 0.96, 0.67, 0.31, and 0.66, respectively. Compared to the individual strains, the mixture (1:1:1) did not show a significantly higher hydrogen level, indicating that there was no synergistic effect. Enterobacter spH1 was selected for further investigation because of its higher yield of hydrogen and ethanol. © 2012 American Institute of Chemical Engineers Biotechnol. Prog., 2013