Antioxidant and membrane-protective properties of an extract from the brown alga <Emphasis Type="Italic">Laminaria japonica</Emphasis>

This paper presents comparative data on the antioxidant and membrane-protective activities of an extract from the brown seaweed Laminaria japonica and the commercial drug Legalon. It was shown that intoxication with carbon tetrachloride was accompanied by the exhaustion of the antioxidant defense system of erythrocytes, an increase in their dimensional characteristics, and a change in the phospholipids to neutral lipids ratio. The Laminaria extract appeared to be more efficient than Legalon in the restoration of the lipid component of erythrocyte membranes and the removal of toxic stress.     

A simple method for DNA extraction from sporophyte in the brown alga <Emphasis Type="Italic">Laminaria japonica</Emphasis>

A simple method was developed for extracting DNA from brown algae Laminaria japonica, which possess large amounts of acidic polysaccharides. Firstly, the sporophyte were washed by eliminating polysaccaride buffer to remove the polysaccharides and then ground in liquid nitrogen. Secondly, the powders were treated with lysing buffer. Thirdly, KAc was used to eliminate the remaining acidic polysaccharides. The extracted DNA was purified using a chloroform-isoamyl alcohol (24:1 v/v), and precipitated in cold isopropanol. The yield was from 18.7 to 37.5 μg g⁻¹ (wet weight) and the purity of total DNA was determined spectrophotometrically as the ratio of A₂₆₀/A₂₈₀, which was about 1.7–1.9. The extracted DNA was of high quality and suitable for molecular analyses, such as PCR, restriction enzyme digestion. This method is a reproducible, simple, and rapid technique for routine DNA extraction from sporophyte in Laminaria japonica. Furthermore, the low cost of this method makes it attractive for large-scale studies.     

Protoplast Preparation from <Emphasis Type="Italic">Laminaria japonica</Emphasis> with Recombinant Alginate Lyase and Cellulase

Functional recombinant abalone alginate lyase (rHdAly) and β-1,4-endoglucanase (rHdEG66) were expressed as secreted proteins with baculoviral expression systems. The specific activity of each recombinant enzyme, 2,490 and 18.2 U/mg for rHdAly and rHdEG66, respectively, was comparable to its native form at 30°C. Purified rHdAly and rHdEG66 showed the highest specific activity both at 35°C and optimum pH 8.7 and 5.9, respectively. These properties were also comparable to those of the native enzymes. Protoplast isolation was attempted from Laminaria japonica using both rHdAly and rHdEG66. When L. japonica blades were incubated in artificial seawater containing rHdAly and rHdEG66, very low numbers of protoplasts (<1 × 10³ protoplasts/g fresh weight) resulted. However, using blades pretreated with proteinase K, the protoplast was increased up to 5 × 10⁶ protoplasts/g fresh weight. Since the average diameter of isolated protoplasts was 11.6 μm, these cells were mostly derived from the epidermal layer rather than the cortical layer. Our results suggest that at least three enzymes, alginate lyase, cellulase, and protease, are essential for effective protoplast isolation from L. japonica. The protoplast isolation method in this study is more useful than earlier methods because it preferentially yielded protoplasts of the epidermal layer, which are known to be able to be regenerated.     

Polysaccharide and lipid composition of the brown seaweed <Emphasis Type="Italic">Laminaria gurjanovae</Emphasis>

Polysaccharide and lipid composition of the Pacific brown seaweed Laminaria gurjanovae is determined. Alginic acid is shown to be the main polysaccharide of its biomass (about 28%); it consists of mannuronic and guluronic acid residues at a ratio of 3: 1. The yield of water-soluble polymannuronic acid is low and does not exceed 1.1% of dry biomass. High laminaran content (about 22%) is found, whereas the yield of fucoidan is no more than 3.6%. Laminaran consists of two fractions, soluble and insoluble in cold water, their ratio is 2.5: 1. Insoluble laminaran is a practically linear 1,3-β-D-glucan, and the soluble fraction was shown to be 1,3;1,6-β-D-glucan. The oligosaccharide products of desulfation or partial acidic hydrolysis of fucoidan were studied by MALDI TOF MS; they were found to be fuco- and galactooligosaccharides. The fucoidan is suggested to be a highly sulfated partially acetylated galactofucan (Fuc/Gal is ～1: 1). The main lipid components of the dried L. gurjanovae are neutral lipids and glyceroglycolipids, whereas phospholipids are found in minor amounts. The main fatty acid components of lipids are 14:0, 16:0, 16:1 ω-7, 18:1 ω-7 and 18:2 ω-6 acids.     

Growth of the Brown Alga <Emphasis Type="Italic">Laminaria japonica</Emphasis> in a Laboratory Environment

The growth of an individual thallus of the brown alga Laminaria japonica was studied in a laboratory environment. It was found that daily accretion of the Laminaria thallus can remain constant for a long time. The blade grew in length at a distance from 0 to 15–25 cm from the stipe-blade border, which makes up 60% of the blade length. In width, the blade grew both in the central and in the lateral parts of the blade, 0 to 7–10 cm from the stipe-blade border, which makes up 30% of the frond length. The transposition of a perforation hole mark from the stipe-blade border toward the blade tip evidenced the formation of new tissue in the growth zone even when the thallus diminished in size due to destruction of the blade tip. Based on the results of this observation, it was concluded that both restraint of accumulation and even reduction of the algal thallus in biomass and size cannot be taken as an indication of algal growth cessation.Original Russian Text Copyright ¢ 2005 by Biologiya Morya, Skriptsova, Leletkin.     

An extract from the brown alga <Emphasis Type="Italic">Laminaria japonica</Emphasis>: a promising stress-protective preparation

It was shown in rats that stress is accompanied by a decrease in osmotic resistance and antioxidant protection of erythrocytes and an increase in their volume and diameter; cholesterol esters were reduced, the amounts of malone dialdehyde, cholesterol, sphingomyelin, and phospholipid lysofractions were increased. Comparative data on the membrane protecting activity of extracts of Laminaria japonica and Eleutherococcus senticosus are presented. Administration of these extracts caused the normalization of the parameters of erythrocytes in rats.     

<Emphasis Type="Italic">Bacillus anthracis</Emphasis>, <Emphasis Type="Italic">Francisella tularensis</Emphasis> and <Emphasis Type="Italic">Yersinia pestis</Emphasis>. The most important bacterial warfare agents — <Emphasis Type="Italic">review</Emphasis>

There are three most important bacterial causative agents of serious infections that could be misused for warfare purposes: Bacillus anthracis (the causative agent of anthrax) is the most frequently mentioned one; however, Fracisella tularensis (causing tularemia) and Yersinia pestis (the causative agent of plague) are further bacterial agents enlisted by Centers for Disease Control and Prevention into the category A of potential biological weapons. This review intends to summarize basic information about these bacterial agents. Military aspects of their pathogenesis and the detection techniques suitable for field use are discussed.     

<Emphasis Type="Italic">Boletus kermesinus</Emphasis>, a new species of <Emphasis Type="Italic">Boletus</Emphasis> section <Emphasis Type="Italic">Luridi</Emphasis> from central Honshu,Japan

Boletus kermesinus, a new species of Boletus section Luridi, is fully described and illustrated based on the materials collected in subalpine coniferous forests of central Honshu, Japan. It has distinctive features of dark-red basidiomata having distinct viscidity in the pileus surface, usually unchanging flesh, discolorous red pores, and an entirely reticulate stipe becoming coarsely lacerate-rimose with age.     

Interaction of <Emphasis Type="Italic">Bdellovibrio bacteriovorus</Emphasis> with bacteria <Emphasis Type="Italic">Campylobacter jejuni</Emphasis> and <Emphasis Type="Italic">Helicobacter pylori</Emphasis>

Interaction of Bdellovibrio bacteriovorus 100NCJB with bacteria Campylobacter jejuni (strains 1, 2, 3, 4, and 5) and Helicobacter pylori, strain TX30a, was confirmed. The results indicate that lytic activity of bdellovibrios both in liquid media and cells attached to a surface was observed. The potential use of the antimicrobial activity of predatory bacteria for environmental bioprotection and public health is discussed.     

High-Level Expression of Heme-Dependent Catalase Gene <Emphasis Type="Italic">katA</Emphasis> from <Emphasis Type="Italic">Lactobacillus Sakei</Emphasis> Protects <Emphasis Type="Italic">Lactobacillus Rhamnosus</Emphasis> from Oxidative Stress

Lactic acid bacteria (LAB) are generally sensitive to hydrogen peroxide (H₂O₂), Lactobacillus sakei YSI8 is one of the very few LAB strains able to degrade H₂O₂ through the action of a heme-dependent catalase. Lactobacillus rhamnosus strains are very important probiotic starter cultures in meat product fermentation, but they are deficient in catalase. In this study, the effect of heterologous expression of L. sakei catalase gene katA in L. rhamnosus on its oxidative stress resistance was tested. The recombinant L. rhamnosus AS 1.2466 was able to decompose H₂O₂ and the catalase activity reached 2.85 μmol H₂O₂/min/10⁸ c.f.u. Furthermore, the expression of the katA gene in L. rhamnosus conferred enhanced oxidative resistance on the host. The survival ratios after short-term H₂O₂ challenge were increased 600 and 10⁴-fold at exponential and stationary phase, respectively. Further, viable cells were 100-fold higher in long-term aerated cultures. Simulation experiment demonstrated that both growth and catalase activity of recombinant L. rhamnosus displayed high stability under environmental conditions similar to those encountered during sausage fermentation.     

Frequencies of the <Emphasis Type="Italic">DRB1</Emphasis>, <Emphasis Type="Italic">DQA1</Emphasis>, <Emphasis Type="Italic">DQB1</Emphasis> and <Emphasis Type="Italic">TNFA</Emphasis> alleles in immigrant population of west Siberia

Based on population analysis of the DRB1, DQA1, DQB1 and TNFA allele frequency distribution patterns, regional features of immunogenetic structure of the population of West Siberia were investigated. Statistically significant linkage disequilibrium within the HLA class II region, as well as between the TNFA and DRB1, DQA1, and DQB1 was demonstrated. Population frequency distribution patterns of two- and multilocus haplotypes were examined.     

Overexpression of the Chitosanase Gene in <Emphasis Type="Italic">Fusarium solani</Emphasis> via <Emphasis Type="Italic">Agrobacterium</Emphasis><Emphasis Type="Italic">tumefaciens</Emphasis>-Mediated Transformation

To overexpress the chitosanase gene (csn) in F. solani, a vector based on pCAMBIA 1300 was constructed. The csn gene, which is under control of the Aspergillus nidulans gpdA promoter and A. nidulans trpC terminator, was introduced back into the F. solani genome by Agrobacterium tumefaciens-mediated transformation, and the herbicide-resistance gene bar from Streptomyces hygroscopicus was used as the selection marker. Transformants which showed a significant increase in chitosanase production (~2.1-fold than control) were obtained. Southern blot analysis indicated that most transformants had a single-copy T-DNA integration.     

In vitro antifungal effects of potassium bicarbonate on <Emphasis Type="Italic">Trichoderma</Emphasis> sp. and <Emphasis Type="Italic">Sclerotinia sclerotiorum</Emphasis>

Bicarbonates are often utilized in the food industry to avoid fermentation and to improve pH, flavor, and texture. In the same manner, bicarbonates have been demonstrated to control postharvest phytopathogens; however, there are no reports describing the effects of these chemical compounds either on soil-borne pathogens such as Sclerotinia sclerotiorum or on antagonist fungi such as Trichoderma species. This study evaluated the antifungal effect of increasing concentrations (0, 2, 4, 6, 8, 10, 25, and 50 mM) of potassium bicarbonate (KHCO₃) on the growth of Trichoderma sp. strain R39 and S. sclerotiorum under in vitro systems. Applications of KHCO₃ greater than 8 mM significantly inhibited (P < 0.001) the growth of both fungi. Concentrations of KHCO₃ lower than 25 mM did not affect the antagonistic effect of Trichoderma on the growth of S. sclerotiorum; however, this fungal interaction was not observed when exposed to 50 mM KHCO₃ because of its strong inhibition of fungal growth. In addition, KHCO₃ concentrations higher than 8 mM caused significant (P < 0.001) reduction of the sclerotium formation of S. sclerotiorum. Sclerotium germination and de novo sclerotium formation were significantly (P < 0.001) inhibited as the concentrations of KHCO₃ increased. Results show the potential benefits of potassium bicarbonate for controlling both growth and development of S. sclerotiorum, although it also exerts negative effects on the Trichoderma strain that is a natural antagonist to S. sclerotiorum.     

<Emphasis Type="Italic">Barleria compacta</Emphasis>: a new species in <Emphasis Type="Italic">Barleria</Emphasis> sect. <Emphasis Type="Italic">Prionitis</Emphasis> (Acanthaceae) from Somalia

Following a re-examination of the material treated under Barleria brevispina (Fiori) Hedrén in the recent Flora of Somalia account of the Acanthaceae, it is concluded that two distinct species are involved and Barleria compacta Malombe & I. Darbysh. is described here from north-eastern Somalia. Its affinities and conservation status are discussed.     

Habitat,density, and spatial distribution of <Emphasis Type="Italic">Rivulus giarettai</Emphasis> (<Emphasis Type="Italic">Actinopterygii</Emphasis>, <Emphasis Type="Italic">Cyprinodontiformes</Emphasis>) in southeastern Brazil

We present data on the habitat, density, and spatial distribution of Rivulus giarettai, and discuss some biotic and abiotic variables related to its abundance in Free Flowing Waters (FFW) and Dam Reservoirs (DR) in palm grove (Mauritia flexuosa) marshes (Veredas) in Uberlandia, Minas Gerais, southeastern Brazil. The mean density (individuals/plot) of R. giarettai was about 13 times higher in FFW than in DR. In FFW, the density of R. giarettai was highest at intermediate amounts of substrate (plant mass) and it was positively rank-correlated with the depth, and the number of arthropods. Individuals occurred in an aggregated distribution. The aggregated pattern could be related to a concentration of individuals in microhabitats neither too much exposed nor completely saturated by plants. R. giarettai was relatively abundant and tolerant to slight man-made habitat modifications. Damming appeared to be especially problematic by negatively affecting its density.     

Structural characteristics of the chloroplast <Emphasis Type="Italic">rpS16</Emphasis> intron in <Emphasis Type="Italic">Allium sativum</Emphasis> and related <Emphasis Type="Italic">Allium</Emphasis> species

The intron sequence of chloroplast rpS16 and the secondary structure of its pre-mRNA were characterized for the first time in 26 Allium sativum accessions of different ecologo-geographical origins and seven related Allium species. The boundaries and main stem-loop consensus sequences were identified for all six domains of the intron. Polymorphism was estimated for the total intron and its regions. The structural regions of the rpS16 intron proved to be heterogeneous for mutation rate and spectrum. Mutations were most abundant in domains II and IV, and transition predominated in domains I, III, V, and VI. In addition to structural elements and motifs typical for group IIB introns, several Allium-specific micro- and macrostructural mutations were revealed. A 290-bp deletion involving domains III and IV and part of domain V was observed in A. altaicum, A. fistulosum, and A. schoenoprasum. Several indels and nucleotide substitutions were found to cause a deviation of the pre-mRNA secondary structure from the consensus model of group II introns.     

Quorum sensing inhibitors from the red alga,<Emphasis Type="Italic">Ahnfeltiopsis flabelliformis</Emphasis>

Three new acylhomoserine lactone (AHL) inhibitors have been isolated from the Korean red alga.Ahnfeltiopsis flabelliformis, via bioactivity-guided fractionation using the recombinantAgrobacterium tumefaciens liquid culture bioassay. Unlike the majority of AHL inhibitors reported to date, these compounds were α-d-galactopyranosyl-(1→2)-glycerol (floridoside) (1), betonicine (2), and isethionic acid (3), all of which are structurally unrelated to AHLs.     

<Emphasis Type="Italic">Hyptis maya</Emphasis>, a new species of <Emphasis Type="Italic">Lamiaceae</Emphasis> from Belize,Central America,and the closely related <Emphasis Type="Italic">H. lanceolata</Emphasis>

A new species of Lamiaceae from Belize: Hyptis maya is described and illustrated. It is closely related to the more widespread H. lanceolata Poir., with which it is compared.