Environmental and health effects associated with Harmful Algal Bloom and marine algal toxins in China

The frequency and scale of Harmful Algal Bloom (HAB) and marine algal toxin incidents have been increasing and spreading in the past two decades, causing damages to the marine environment and threatening human life through contaminated seafood. To better understand the effect of HAB and marine algal toxins on marine environment and human health in China, this paper overviews HAB occurrence and marine algal toxin incidents, as well as their environmental and health effects in this country. HAB has been increasing rapidly along the Chinese coast since the 1970s, and at least 512 documented HAB events have occurred from 1952 to 2002 in the Chinese mainland. It has been found that PSP and DSP toxins are distributed widely along both the northern and southern Chinese coasts. The HAB and marine algal toxin events during the 1990s in China were summarized, showing that the HAB and algal toxins resulted in great damages to local fisheries, marine culture, quality of marine environment, and human health. Therefore, to protect the coastal environment and human health, attention to HAB and marine algal toxins is urgently needed from the environmental and epidemiological view.

A mechanistic model of algal photoinhibition induced by photodamage to Photosystem-II

Photoinhibition is a central problem for the understanding of plasticity in photosynthesis vs. irradiance response. It effectively reduces the photosynthetic rate. In this contribution, we present a mechanistic model of algal photoinhibition induced by photodamage to photosystem-II. Photosystem-IIs (PSIIs) are assumed to exist in three states: open, closed and inhibited. Photosynthesis is closely associated with the transitions between the three states. The present model is defined by four parameters: effective cross section of PSII, number of PSIIs, turnover time of electron transfer chains and the ratio of rate constant of damage to that of repair of D1 proteins in PSIIs. It gives a photosynthetic response curve of phytoplankton to irradiance (PI-curve). Without photoinhibition, the PI-curve is in hyperbola with the first three parameters. The PI-curve with photoinhibition can be simplified to the same form as the hyperbola by replacing either the number of PSIIs with the number of functional PSIIs or the turnover time of electron transfer chains with the average turnover time.

Impact of germanium on the growth of Pseudonitzschia pungens f. multiseries and the production of algal toxin

The impacts of germanic acid Ge(OH)(4) on the growth of Psuedonitzschia pungens f. multiseries and on the production of the algal toxin, domoic acid, were studied. The results showed that germanic acid in the range of concentrations could inhibit the growth of the algal cells and the inhibition was enhancing with the concentrations of germanic acid increasing. Germanic acid also could inhibit the production of the algal toxin, domoic acid in cells and the inhibition reached up to 100% at Ge/Si = 35. Based on the results, the mechanism was discussed.

Antioxidant activity of different sulfate content derivatives of polysaccharide extracted from Ulva pertusa (Chlorophyta) in vitro

Polysaccharide extracted from Ulva pertusa (Chlorophyta) is a group of sulfated heteropolysaccharide; for simplicity, the sulfated polysaccharide is referred to as ulvan in this paper. In this study, different sulfate content ulvans were prepared with sulfur trioxide/N,N-diinethylformamide (SO3-DMF) in formamide, and their antioxidant activities were investigated including scavenging activity of superoxide and hydroxyl radicals, reducing Power and metal chelating ability. As expected, we obtained several satisfying results, as follows: firstly, high sulfate content ulvans had more effective scavenging activity on hydroxyl radical than natural ulvan. Secondly, comparing with natural ulvan, high sulfate content ulvans exhibited stronger reducing power. Thirdly, HU4 (sulfate content, 30.8%) and HU5 (sulfate content, 32.8%) showed more pronounce chelating ability on ferrous ion at high concentration than other samples. (c) 2005 Elsevier B.V. All rights reserved.

Chemical characteristics of a polysaccharide from Porphyra capensis (Rhodophyta)

The structure of a polysaccharide from the red seaweed, Porphyra capensis, growing along the coast of Namibia and South Africa was investigated. Algae growing at different sites and collected at different times gave a polysaccharide extract with similar chemical components. FTIR and NMR spectral analysis showed that the polysaccharide from P. capensis had a typical porphyran structure. It has the linear backbone of alternating 3-linked beta-D-galactose and 4-linked alpha-L-galactose-6-sulfate or 3,6-anhydro-alpha- L-galactose units. The ratio of alpha-L-galactose-6-sulfate and the 3,6-anhydrogalactose is 121, as reflected by a H-1 NMR spectrum. A high degree of methylation occurred at the C-6 position of the D-galactose units. The degree of methylation was 0.64 for the D-galactose residues. (C) 2005 Elsevier Ltd. All rights reserved.

Antioxidant activities of sulfated polysaccharide fractions from Porphyra haitanesis

Three sulfated polysaccharide fractions (F1, F2, and F3) were isolated from Porphyra haitanesis, an important economic alga in China, through anion-exchange column chromatography and their in vitro antioxidant activities were investigated in this study. Galactose was the main sugar unit of the three fractions. The analytical results indicated that polysaccharide fractions from P. haitanesis had similar chemical components to porphyran from other species, but differed in their high sulfate content. The sulfate content of F1, F2 and F3 was 17.4%, 20.5% and 33.5% respectively. All three polysaccharide fractions showed antioxidant activities. They had strong scavenging effect on superoxide radical, and much weaker effect on hydroxyl free radical. Lipid peroxide in rat liver microsome was significantly inhibited, and H2O2 induced hemolysis of rat erythrocyte was partly inhibited by F1, F2 and F3. Among them, F3 showed strongest scavenging effect on superoxide radical; F2 had strongest effect on hydroxyl radical and lipid peroxide.

In vivo antioxidant activity of polysaccharide fraction from Porphyra haitanesis (Rhodephyta) in aging mice

Sulfated polysaccharide fraction F2 from Porphyra haitanesis (Rhodephyta) showed inhibitory effect on the in vitro lipid peroxidation. In the present study, the age-related changes in the antioxidant enzyme activity, lipid peroxidation, and total antioxidant capacity (TAOC) in different organs in mice were investigated and the in vivo antioxidant effect of F2 in aging mice was checked. Increased endogenous lipid peroxidation and decreased TAOC were observed in aging mice. Intraperitoneal administration of F2 significantly decreased the lipid peroxidation in a dose-dependent manner. F2 treatment increased TAOC and the activity of superoxide dismutase (SOD) and glutathione peroxidase (GSH-Px) in all the organs tested in aging mice. It is concluded that the sulfated polysaccharide fraction F2 can be used in compensating the decline in TAOC and the activities of antioxidant enzymes and thereby reduces the risks of lipid peroxidation. (C) 2003 Elsevier Science Ltd. All rights reserved.

Antioxidant activity of sulfated polysaccharide fractions extracted from Laminaria japonica

Fucoidan, a group of sulfated heteropolysaccharide, was extracted from Laminaria japonica, an important economic alga species in China. Three sulfated polysaccharide fractions (F1, F2, and F3) were successfully isolated through anion-exchange column chromatography and had their antioxidant activities investigated employing various established in vitro systems, including superoxide and hydroxyl radical scavenging activity, chelating ability, and reducing power. Chemical analysis suggested that F1 and F3 were heteropolysaccharide in which galactose was the major component, while F2 was a typical fucoidan. All fractions possessed considerable antioxidant activity, and F1, F2 and F3 had stronger antioxidant ability than fucoidan in certain tests. The correlation between the sulfate content and scavenging superoxide radical ability was positive. Available data obtained with in vitro models suggested that the ratio of sulfate content/fucose was an effective indicator to antioxidant activity of the samples. (C) 2007 Elsevier B.V. All rights reserved.

Impact of astaxanthin-enriched algal powder of Haematococcus pluvialis on memory improvement in BALB/c mice

The impact of astaxanthin-enriched algal powder on auxiliary memory improvement was assessed in BALB/c mice pre-supplemented with different dosages of cracked green algal (Haematococcus pluvialis) powder daily for 30 days. The supplemented mice were first tested over 8 days to find a hidden platform by swimming in a Morris water maze. Then, for 5 days, the mice were used to search for a visible platform in a Morris water maze. After that, the mice practised finding a safe place-an insulated platform in a chamber-for 2 days. During these animal experimental periods, similar algal meals containing astaxanthin at 0, 0.26, 1.3 and 6.4 mg/kg body weight were continuously fed to each group of tested mice. Profiles of latency, distance, speed and the direction angle to the platforms as well as the diving frequency in each group were measured and analyzed. The process of mice jumping up onto the insulated platform and diving down to the copper-shuttered bottom with a 36 V electrical charge were also monitored by automatic video recording. The results of the Morris maze experiment showed that middle dosage of H. pluvialis meals (1.3 mg astaxanthin/kg body weight) significantly shortened the latency and distance required for mice to find a hidden platform. However, there was no obvious change in swim velocity in any of the supplemented groups. In contrast, the visible platform test showed a significant increase in latency and swim distance, and a significant decrease in swim speed for all groups of mice orally supplemented with H. pluvialis powder compared to the placebo group (P < 0.05 or P < 0.01). Mice supplemented with the algal meal hesitantly turned around the original hidden platform, in contract to mice supplemented with placebo, who easily forgot the original location and accepted the visible platform as a new safe place. These results illustrate that astaxanthin-enriched H. pluvialis powder has the auxiliary property of memory improvement. The results from the platform diving test showed that the low and middle dosage of H. pluvialis powder, rather that the high dosage, increased the latency and reduced the frequency of diving from the safe insulated platform to the electrically stimulated copper shutter, especially in the low treatment group (P < 0.05). These results indicate that H. pluvialis powder is associated with dose-dependent memory improvement and that a low dosage of algal powder (<= middle treatment group) is really good for improving the memory.

In vitro antioxidant activity of acetylated and benzoylated derivatives of polysaccharide extracted from Ulva pertusa (Chlorophyta)

The antioxidant activity of natural ulvan and its derivatives (acetylated and benzoylated ulvans) in vitro was determined, including scavenging activity against superoxide and hydroxyl radicals, reducing power, and chelating ability. Obvious differences in antioxidant activity between natural ulvan and its derivatives were observed, moreover, the antioxidant activity of acetylated and benzoylated ulvans was stronger than that of natural ulvan. (C) 2006 Elsevier Ltd. All rights reserved.

Jiangella gansuensis gen. nov., sp nov., a novel actinomycete from a desert soil in north-west China

A novel actinomycete strain, designated YIM 002(T), was isolated from a desert soil sample in Gansu Province, north-west China. This actinomycete isolate formed well-differentiated aerial and substrate mycelia. In the early stages of growth, the substrate mycelia fragmented into short or elongated rods. Chemotaxonomically, it contained LL-2,6-diaminopimelic acid in the cell wall. The cell-wall sugars contained ribose and glucose. Phospholipids present were phosphatidylinositol mannosides, phosphatidylinositol and diphosphatidylglycerol. MK-9(H-4) was the predominant menaquinone. The major fatty acids were anteiso C-15:0 (35.92%), anteiso C-17:0 (15.84%), iso C-15:0 (10.40%), iso C-16:0 (7.07%) and C(17:10)w8c (9.37%). The G+C content of the DNA was 70 mol%. Phylogenetic analysis and signature nucleotide data based on 16S rRNA gene sequences showed that strain YIM 002(T) is distinct from all recognized genera of the family Nocardioidaceae in the suborder Propionibacterineae. On the basis of the phenotypic and genotypic characteristics, it is proposed that isolate YIM 002(T) be classified as a novel species in a new genus, Jiangella gansuensis gen. nov., sp. nov. The type strain is YIM 002(T) (= DSM 44835(T) = CCTCC AA 204001(T) = KCTC 19044(T)).

Analyses of patterns of copper and lead mineralisation in human skeletons excavated from an ancient mining and smelting centre in the Jordanian desert

Grattan, J.P., Al-Saad, Z., Gilbertson, D.D., Karaki, L.O., Pyatt, F.B 2005 Analyses of patterns of copper and lead mineralisation in human skeletons excavated from an ancient mining and smelting centre in the Jordanian desert Mineralogical Magazine. 69(5) 653-666.

Radon and King Solomons Miners: Faynan Orefeild, Jordanian desert

Grattan, J. Gilmore, G. Gilbertson, D. Pyatt, F.B. HUnt, C. McLaren, S. Phillips, P. Denman, A. Radon and King Solomons Miners: Paynan Orefield, Jordanian Desert. The Science of the Total Environment. 2004 319 pp 99-113

The local and global dimensions of metalliferous pollution derived from a reconstruction of an eight thousand year record of copper smelting and mining at a desert-mountain frontier in southern Jordan

Grattan, J.P., Gilbertson, D.D., Hunt, C.O. (2007). The local and global dimensions of metaliferrous air pollution derived from a reconstruction of an 8 thousand year record of copper smelting and mining at a desert-mountain frontier in southern Jordan. Journal of Archaeological Science 34, 83-110