<Emphasis Type="Italic">Undaria pinnatifida</Emphasis> fucoidan extract protects against CCl<Subscript>4</Subscript>-induced oxidative stress

This study was performed to elucidate the effects of Undaria pinnatifida fucoidan extract (UPFE) in preventing CCl₄-induced oxidative stress. UPFE (100 mg/kg) was intraperitoneally administered to rats for 14 days. On day 15, CCl₄ dissolved in olive oil (50% CCl₄) was injected 12 h before they were anesthetized and dissected. To measure UPFE-mediated antioxidation, we examined the levels of glutamate oxaloacetate transaminase (GOT), glutamate pyruvate transaminase (GPT), alkaline phosphatase (ALP), and lactate dehydrogenase (LDH) in serum, as well as malondialdehyde (MDA), superoxide dismutase (SOD), catalase (CAT), and glutathione peroxidase (GPx) in liver homogenates. CCl₄ treatment markedly increased the levels of GOT, GPT, ALP, LDH, and MDA and significantly decreased levels of SOD, CAT, and GPx. UPFE pretreatment decreased levels of GOT, GPT, ALP, LDH, and MDA, by 62.8, 68.5, 41.9, 72.7, and 122%, respectively and increased those of SOD, CAT, and GPx by 111.1, 15.9, and 52.6%, respectively. These results showed that UPFE has antioxidant effects against CCl₄-induced oxidative stress.     

Growth Promotion of Vegetative Gametophytes of <Emphasis Type="Italic">Undaria pinnatifida</Emphasis> by Blue Light

Through an acclimation period of 10 days, compared to white light, the maximal net photosynthetic rates were significantly higher for gametophytes of Undaria pinnatifida cultivated under blue light (400–500 nm), and were lower under red light (600–700 nm). Chlorophyll c and the carotenoid content of gametophytes were similar under blue light and red light but were much lower under white light. The growth rate of female gametophytes under blue light was higher than that under other lights, and the growth rate of male gametophytes showed little variation with respect to blue and white light. Male and female gametophytes were mixed together to form sporophytes under white, blue and red light. After approximately 5 days, 50% gametophytes became fertile under blue and white light, but remained vegetative under red light after 10 days.     

Monthly changes in the content and monosaccharide composition of fucoidan from <Emphasis Type="Italic">Undaria pinnatifida</Emphasis> (Laminariales,Phaeophyta)

Crude fucoidan was extracted from the brown alga Undaria pinnatifida collected monthly from April to last July in Peter the Great Bay (Japan Sea, Russia). The amount of crude fucoidan rose markedly from April to June–July (from 3.2 to 16.0% dry weight) as the plant matures. An analysis of the monosaccharide composition of the fucoidan extracted showed that the alga synthesized polysaccharides with various structures which were dependent on the algae age. In juvenile plants collected in April–May, this was represented by sulfated manno-galactofucan containing up to 19–28 mol% of mannose and about 20 mol% of galactose, whereas in matured plants collected in June–July, the polysaccharide was represented by a sulfated galactofucan containing more than 38 mol% galactose. It is postulated that the production of sori causes a subsequent effect on fucoidan synthesis and leads to an enhanced of crude fucoidan content and an increased molar concentration of galactose. Crude fucoidan content in sporophylls increased 5 times, and galactose content in this polysaccharide rose s1.6 times with sori formation. The structural characteristics of the fucoidan extracted from sporophylls of Undaria collected in July were also studied. The fractionation of crude fucoidan on DEAE-Sephadex A-25 gave two fractions, F1 and F2 in equal quantities. F1 was characterized as manno-galactofucan sulfate and F2 was galactofucan sulfate. The molecular weights of both fractions were in a range of 30–80 kDa. Analysis of fucoidan structure using ESI-FTICR mass spectrometry showed the presence of mixed oligosaccharides consisting of fucose and galactose. Presumably, the polysaccharide molecules contain blocks built up of successively linked residues of fucose and galactose. These blocks are built from two to five or more residues of monosaccharides. According to IR-spectroscopy data, the main portion of sulfates is located at C2; in addition, sulfate esters are also present at C4 on the fucose and C3 and C6 of the galactose units.     

<Emphasis Type="Italic">Ty</Emphasis>1<Emphasis Type="Italic">/copia</Emphasis>- and <Emphasis Type="Italic">Ty</Emphasis>3<Emphasis Type="Italic">/gypsy</Emphasis>-like DNA sequences in <Emphasis Type="Italic">Helianthus </Emphasis>species

Two repeated DNA sequences isolated from a partial genomic DNA library of Helianthus annuus, p HaS13 and p HaS211, were shown to represent portions of the int gene of a Ty3 /gypsy retroelement and of the RNase-Hgene of a Ty1 /copia retroelement, respectively. Southern blotting patterns obtained by hybridizing the two probes to BglII- or DraI-digested genomic DNA from different Helianthus species showed p HaS13 and p HaS211 were parts of dispersed repeats at least 8 and 7 kb in length, respectively, that were conserved in all species studied. Comparable hybridization patterns were obtained in all species with p HaS13. By contrast, the patterns obtained by hybridizing p HaS211 clearly differentiated annual species from perennials. The frequencies of p HaS13- and p HaS211-related sequences in different species were 4.3x10(4)-1.3x10(5) copies and 9.9x10(2)-8.1x10(3) copies per picogram of DNA, respectively. The frequency of p HaS13-related sequences varied widely within annual species, while no significant difference was observed among perennial species. Conversely, the frequency variation of p HaS211-related sequences was as large within annual species as within perennials. Sequences of both families were found to be dispersed along the length of all chromosomes in all species studied. However, Ty3 /gypsy-like sequences were localized preferentially at the centromeric regions, whereas Ty1/ copia-like sequences were less represented or absent around the centromeres and plentiful at the chromosome ends. These findings suggest that the two sequence families played a role in Helianthusgenome evolution and species divergence, evolved independently in the same genomic backgrounds and in annual or perennial species, and acquired different possible functions in the host genomes.     

Revision of the <Emphasis Type="Italic">Serrulati</Emphasis> species of <Emphasis Type="Italic">Penstemon</Emphasis> section <Emphasis Type="Italic">Saccanthera</Emphasis> subsection <Emphasis Type="Italic">Serrulati</Emphasis>

A revision of Penstemon sect. Saccanthera subsect. Serrulati includes a new species (P. salmonensis), a new variety (P. triphyllus var. infernalis), and the elevation of a subspecies to species (P. curtiflorus), bringing the total number of species to eight, which are keyed and described, complete with nomenclature and type citations.     

<Emphasis Type="Italic">Galleria</Emphasis><Emphasis Type="Italic">mellonella</Emphasis> are Resistant to <Emphasis Type="Italic">Pneumocystis</Emphasis><Emphasis Type="Italic">murina</Emphasis> Infection

Studying Pneumocystis has proven to be a challenge from the perspective of propagating a significant amount of the pathogen in a facile manner. The study of several fungal pathogens has been aided by the use of invertebrate model hosts. Our efforts to infect the invertebrate larvae Galleria mellonella with Pneumocystis proved futile since P. murina neither caused disease nor was able to proliferate within G. mellonella. It did, however, show that the pathogen could be rapidly cleared from the host.     

<Emphasis Type="Italic">Agrobacterium</Emphasis><Emphasis Type="Italic">tumefaciens</Emphasis>-mediated transformation of callus cells of <Emphasis Type="Italic">Crataegus</Emphasis><Emphasis Type="Italic">aronia</Emphasis>

A genetic transformation system has been developed for callus cells of Crataegus aronia using Agrobacterium tumefaciens. Callus culture was established from internodal stem segments incubated on Murashige and Skoog (MS) medium supplemented with 5 mg l⁻¹ Indole-3-butyric acid (IBA) and 0.5 mg l⁻¹ 6-benzyladenine (BA). In order to optimize the callus culture system with respect to callus growth and coloration, different types and concentrations of plant growth regulators were tested. Results indicated that the best average fresh weight of red colored callus was obtained on MS medium supplemented with 2 mg l⁻¹ 2,4-dichlorophenoxyacetic acid (2,4-D) and 1.5 mg l⁻¹ kinetin (Kin) (callus maintenance medium). Callus cells were co-cultivated with Agrobacterium harboring the binary plasmid pCAMBIA1302 carrying the mgfp5 and hygromycin phosphotransferase (hptII) genes conferring green fluorescent protein (GFP) activity and hygromycin resistance, respectively. Putative transgenic calli were obtained 4 weeks after incubation of the co-cultivated explants onto maintenance medium supplemented with 50 mg l⁻¹ hygromycin. Molecular analysis confirmed the integration of the transgenes in transformed callus. To our knowledge, this is the first time to report an Agrobacterium-mediated transformation system in Crataegus aronia.     

Extraction of fucoxanthin and polyphenol from <Emphasis Type="Italic">Undaria pinnatifida</Emphasis> using supercritical carbon dioxide with co-solvent

Extraction of brown seaweed (Undaria pinnatifida) oil was carried out by using supercritical carbon dioxide (SCO₂) and ethanol as co-solvent. The flow rate of ethanol was 3.0% (v/v) as compared to that of SCO₂. Experiments were performed in a semi-batch flow apparatus on dried samples at temperatures from 303 to 333 K and pressures from 80 to 300 bar. Fucoxanthin and polyphenol were quantitatively analyzed by using HPLC and UV-spectrometer. The highest yields of fucoxanthin and polyphenol were shown at 200 bar, 323 K and 250 bar, 333 K, respectively. The solubility of fucoxanthin in SCO₂ agreed well with the Chrastil model.     

<Emphasis Type="Italic">Diplazium</Emphasis> hybrids involving <Emphasis Type="Italic">D. plantaginifolium</Emphasis> and <Emphasis Type="Italic">D</Emphasis>. <Emphasis Type="Italic">ternatum</Emphasis> from Mexico and Central America

Here we evaluate the origins and relationships of Mexican and Central American Diplazium hybrids derived from crosses involving either D. plantaginifolium or D. ternatum. Based on study of live plants and herbarium specimens, we distinguish D. ×verapax from the similar D. riedelianum and present evidence that the former is a sterile hybrid derived from a cross between D. plantaginifolium and D. werckleanum. We also describe new hybrids, D. ×torresianum and D. ×subternatum from Mexico and northern Central America. Both involve D. ternatum as one parent. Diplazium. cristatum is the other putative parent of D. ×torresianum, and D. plantaginifolium is the second parent of D. ×subternatum. We also designate lectotypes for D. cordovense and D. dissimile.     

Characterization of <Emphasis Type="Italic">Fusarium graminearum</Emphasis> inhibitory lipopeptide from <Emphasis Type="Italic">Bacillus subtilis</Emphasis> IB

Bacillus subtilis strain IB exhibiting inhibitory activity against the Fusarium head blight disease fungus Fusarium graminearum was isolated and identified. The major inhibitory compound was purified from the culture broth through anion exchange, hydrophobic interaction, and reverse phase high-performance liquid chromatography (RP-HPLC) steps. It was a 1,463-Da lipopeptide and had an amino acid composition consisting of Ala, Glx, Ile, Orn, Pro, Thr, and Tyr at a molar ratio of 1:3:1:1:1:1:2. Electrospray ionization mass spectrometry/mass spectrometry (ESI MS/MS) analyses of the natural and the ring-opened peptides showed the antagonist was fengycin, a kind of macrolactone molecule with antifungal activity produced by several Bacillus strains. Fluorescence microscopic analysis indicated this peptide permeabilized and disrupted F. graminearum hyphae.     

The <Emphasis Type="Italic">Caenorhabditis</Emphasis><Emphasis Type="Italic">briggsae</Emphasis> genome contains active <Emphasis Type="Italic">CbmaT1</Emphasis> and <Emphasis Type="Italic">Tcb1</Emphasis> transposons

The maT clade of transposons is a group of transposable elements intermediate in sequence and predicted protein structure to mariner and Tc transposons, with a distribution thus far limited to a few invertebrate species. We present evidence, based on searches of publicly available databases, that the nematode Caenorhabditis briggsae has several maT-like transposons, which we have designated as CbmaT elements, dispersed throughout its genome. We also describe two additional transposon sequences that probably share their evolutionary history with the CbmaT transposons. One resembles a fold back variant of a CbmaT element, with long (380-bp) inverted terminal repeats (ITRs) that show a high degree (71%) of identity to CbmaT1. The other, which shares only the 26-bp ITR sequences with one of the CbmaT variants, is present in eight nearly identical copies, but does not have a transposase gene and may therefore be cross mobilised by a CbmaT transposase. Using PCR-based mobility assays, we show that CbmaT1 transposons are capable of excising from the C. briggsae genome. CbmaT1 excised approximately 500 times less frequently than Tcb1 in the reference strain AF16, but both CbmaT1 and Tcb1 excised at extremely high frequencies in the HK105 strain. The HK105 strain also exhibited a high frequency of spontaneous induction of unc-22 mutants, suggesting that it may be a mutator strain of C. briggsae.     

Screening and molecular identification of lactic acid bacteria from <Emphasis Type="Italic">gari</Emphasis> and <Emphasis Type="Italic">fufu</Emphasis> and <Emphasis Type="Italic">gari</Emphasis> effluents

Bacterial strains were isolated from cassava-derived food products and, for the first time, from cassava by-products, with a focus on gari, a flour-like product, and the effluents from the production processes for gari and fufu (a dough also made from cassava flour). A total of 47 strains were isolated, all of which were tested to determine their resistance to acidic pH and to bile salt environments. Four of the 47 isolates tested positive in both environments, and these four isolates also showed antibacterial behaviour towards both Gram-positive and Gram-negative microbial pathogens (i.e. Methicillin-resistance Staphylococcus aureus, Listeria monocytogenes, Bacillus cereus, Salmonella enteritidis, Escherichia coli, Escherichia coli (O157), Yersinia enterocolitica). In most cases, the antibacterial activity was related to bacteriocin production. Molecular identification analysis (16S rDNA and randomly amplified polymorphic DNA-PCR) revealed that the four isolates were different strains of the same species, Lactobacillus fermentum. These results demonstrate that bacteria isolated from cassava-derived food items and cassava by-products have interesting properties and could potentially be used as probiotics.     

Structural characteristics and <Emphasis Type="Italic">in vitro</Emphasis> macrophage activation of acetyl fucoidan from <Emphasis Type="Italic">Cladosiphon okamuranus</Emphasis>

We investigated a structural characteristics of acetyl fucoidan (CAF) isolated from commercially cultured Cladosiphon okamuranus. The CAF-induced macrophage activation and its signaling pathways in murine macrophage cell line, RAW 264.7 were also investigated. From the results of methylation analysis, CAF consisted of α-1→3 linked l-fucosyl residues and substituted sulfate and acetyl groups at C-4 on the main chain. CAF induced production of nitric oxide (NO), tumor necrosis factor-α and interleukin-6 in RAW 264.7 cells. Sulfate and acetyl groups of CAF involved in CAF-induced NO production. Neutralizing anti-Toll-like receptor 4 (TLR4), anti-CD14 and anti-scavenger receptor class A (SRA) but not anti-complement receptor type 3 monoclonal antibodies decreased CAF-induced NO production. The results of immunoblot analysis indicated that CAF activated mitogen-activated protein kinases (MAPKs) such as p38 MAPK, extracellular signal-regulated kinase (ERK)1/2 and stress-activated protein kinase/c-Jun N-terminal kinase (SAPK/JNK). SB203580 (p38 MAPK inhibitor) and SP600125 (SAPK/JNK inhibitor), but not U0126 (MAPK/ERK kinase 1/2 inhibitor) decreased CAF-induced NO production. The results suggested that CAF induced macrophage activation through membrane receptors TLR4, CD14 and SRA, and MAPK signaling pathways.     

In planta transformation of <Emphasis Type="Italic">Notocactus scopa</Emphasis> cv. <Emphasis Type="Italic">Soonjung</Emphasis> by <Emphasis Type="Italic">Agrobacterium </Emphasis><Emphasis Type="Italic">tumefaciens</Emphasis>

Notocactus scopa cv. Soonjung was subjected to in planta Agrobacterium tumefaciens-mediated transformation with vacuum infiltration, pin-pricking, and a combination of the two methods. The pin-pricking combined with vacuum infiltration (20-30 cmHg for 15 min) resulted in a transformation efficiency of 67-100%, and the expression of the uidA and nptII genes was detected in transformed cactus. The established in planta transformation technique generated a transgenic cactus with higher transformation efficiency, shortened selection process, and stable gene expression via asexual reproduction. All of the results showed that the in planta transformation method utilized in the current study provided an efficient and time-saving procedure for the delivery of genes into the cactus genome, and that this technique can be applied to other asexually reproducing succulent plant species.     

Phenotypic Switching of <Emphasis Type="Italic">Cryptococcus neoformans</Emphasis> and <Emphasis Type="Italic">Cryptococcus</Emphasis><Emphasis Type="Italic">gattii</Emphasis>

Microorganisms that live in fluctuating environments must constantly adapt their behavior to survive. The host constitutes an important microenvironment in opportunistic and primary fungal pathogens like Cryptococcus neoformans (C. neoformans) and Cryptococcus gattii (C. gattii). In clonal populations, adaptation may be achieved through the generation of diversity. For fungi phenotype switching constitutes a mechanism that allows them to change rapidly. Both C. neoformans and C. gattii undergo phenotypic switching, which allows them to be successful pathogens and cause persistent disease. Similar to other encapsulated microbes that exhibit phenotypic variation, phenotypic switching in Cryptococcus changes the polysaccharide capsule. Most importantly, in animal models phenotypic switching affects virulence and can change the outcome of infection. Virulence changes because C. neoformans and C. gattii switch variants elicit different inflammatory responses in the host. This altered host response can also affect the response to antifungal therapy and in some cases may even promote the selection of switch variants. This review highlights the similarity and differences between phenotypic switching in C. neoformans and C. gattii, the two dominant species that cause cryptococcosis in humans.     

Biochemical and molecular characterization of <Emphasis Type="Italic">Cronobacter</Emphasis> spp<Emphasis Type="Italic">.</Emphasis> (formerly <Emphasis Type="Italic">Enterobacter sakazakii</Emphasis>) isolated from foods

The aim of this study was to identify and characterize Cronobacter spp. isolated from a range of foods. A total of 71 Cronobacter strains were isolated from 602 foods in our laboratory. The highest contamination was observed in foods of plant origin, e.g. spices, teas, chocolate, nuts, pastries and vegetables. On the basis of genus and species identification performed using genus-specific PCR, 16S rRNA sequencing and AFLP genotyping, most of the strains belonged to Cronobacter sakazakii. Biochemical profiling by the tests included in API 20E, complemented with relevant additional tests, classified the strains into 13 biogroups. AFLP genotyping facilitated discrimination of six main groups at the 70% similarity level and strain grouping correlated clearly with species identification. Our results indicate that molecular typing by AFLP may be applied as a useful tool not only for direct comparison of Cronobacter isolates, providing traceability, but also for the reliable species classification. Moreover, tracing of these bacteria in a wider variety of foods should be important to enhance the knowledge of their transmission.