ISOLATION, PURIFICATION AND CHARACTERIZATION OF THE HYDROGEN EVOLUTION PROMOTING FACTOR OF HYDROGENASE OF SPIRULINA PLATENSIS

A component (s-factor) with obvious promoting effect on hydrogen evolution of hydrogenase has beenisolated and extracted from a Cell=free preparation of Spirulina platensis.The effect of the s-factor in the re-action system is similar to that of Na_2S_2O_4, but is coupled with ligh. The s-factor has the maximumabsorption peak at 620 nm in the oxidized state, at 590 nm in the reduced state. The partially purifieds-factor showed two bands by SDS-PAGE and is distinctly different from phycocyanin,which has nochange of oxidized state and reduced state absorption spectra, and also has no promoting effect onhydrogenase of Spirulina platensis under the light.     

Bioaccumulation of Pb^2＋ and Its Effects on Growth, Morphology and Pigment Contents of Spirulina （Arthrospira）platensis

A laboratory experiment was conducted to assess the bioaccumulation of Pb2 and its effects on growth,morphology andpigment contents of Spirulina (Arthrospira) platensis.The specimen cultured in Zarrouk liquid medium was treated with variousinitial metal concentrations (0,5,10,30,50 and 100 μgmL-1).The growth of S.platensis was adversely affected by Pb2 at high con-centrations (30,50 and 100 μg mL-1).However,at low concentrations (5 μg mL-1),Pb2 could stimulate its growth slightly.The pig-ment contents (chlorophyll α and β carotene) were decreased in a dose-dependent manner.The highest reductions (67% and 53%respectively in chlorophyll α and β carotene) were observed in 100 μg mL-1 treatment group.The LC50 (96 h) of Pb2 was measured as75.34μg mL-1.Apart from a few cases of filament breakages at elevated concentrations (50 and 100μg mL-1),morphological abnor-malities are not specific.Metal bioaccumulation increased with Pb2 concentrations,but decreased with exposure time.The maxi-mum accumulated amount was 188 mgg-1 dry weight.The bioconcentration factor (BCF) reached to a peak at day 2,followed by agradual reduction for all the exposure concentrations.S.platensis is able to tolerate considerably high Pb2 concentrations.Conse-quently it can be used as a potential species to remove heavy metal from contaminated waters.     

Toxicity and Accumulation of Selenite in Four Microalgae

The toxicity and bioaccumulation of selenite in four microalgae, Spirulina platensis,Dunaliella salina, DunalieUa bardawill and Phaeodactylum tricornutum cultured in the presence of selenite were investigated. Lower concentrations of selenite were generally nontoxic and frequently stimulated algal growth, while higher concentrations of selenite inhibited algal growth. Selenite was more toxic to D. salina and D. bardawill than to S. platensis and P. tricornutum. All algae cultured in selenite were able to incorporate Se to different degrees, which depended on algal species. The distributions of selenite among intracellular macromolecular compounds were different among algal species : most of the selenite was associated with proteins in S. platensis, D. salina and D. bardawill, while most of the selenite was associated with lipids in P. tricornutum, which reflected the physiological differences among the algae. These observations suggest that algae are able to accumulate selenite and bind it with intracell~ar macromolecular compounds when exposed to high concentration of selenite. This may represent a form of storage or detoxification of selenite by the algae.     

Effect of germanium dioxide on growth of Spirulina platensis

This study on the effect of different concentrations of germanium dioxide (GeO₂) on the specific growth rate (SGR), pigment contents, protein content and amino acid composition ofSpirulina platensis showed that Ge was not the essential element of this alga; that GeO₂ could speed up growth and raise protein content ofS. platensis, and could possibly influence the photosynthesis system. The concentration range of GeO₂ beneficial to growth ofS. platensis is from 5–100mg/l. GeO₂ is proposed to be utilized to remove contamination byChlorella spp. usually occurring in the cultivation ofSpirulina.     

PROMOTIVE EFFECT OF Se ON THE GROWTH AND ANTIOXIDATION OF A BLUE-GREEN ALGA SPIRULINA MAXIMA

ItwasreportedthatthegrOwthofthedrinediatomffelassforiraPsethenana(Hust.)HasleetHeiIndaldependedonSe(Priceetal.,1987).ThisreqUirementissPecificforSe;nootherelementscansubstituteforit,becauseSecaninduceglutathioneperoxidase(GSH-PoD)activityinthisdiatom(PriceandHarrison,l988),andinlow-CO2-grooCham~nasreinhandiiDangerad(Yokotaetal.,l988).ThisenZyInac-tivitywdetectedinextractsOfablue-greenalgaGleeoCaPasp.LB795(TotaandGallon,l979),andalsoincultUredhigherplancells(Drotaretal.,1985),butw…     

螺旋藻对乌鬃鹅生长性能、屠宰性能和肌肉营养的影响

选取1 日龄乌鬃鹅300 只,随机分成5 组,对照组（A）用基础饲粮饲养,实验组B～E 组分别在基础饲粮中添加质量分数1%（B 组）、2%（C 组）、3%（D 组）、4%（E 组）的螺旋藻,实验期63 d.结果表明：与对照组相比,添加螺旋藻对乌鬃鹅的屠宰率、半净膛率、腹脂率和肌肉灰分无显著影响（P〉0.05）,对其它生长指标和全净膛率均有显著性影响（P〈0.05）,其中2%C 组和3% D 组的料重比显著下降（P〈0.05）, E 组全净膛率显著提高（P〈0.05）;肌肉的粗蛋白质（CP）含量E〉D〉C〉B〉A,粗脂肪（EE）含量E〉A〉B〉C〉D;所测得的17 种氨基酸中,包括含有人体必需的7 种氨基酸（EAA）和2 种半必需氨基酸（HEAA）;氨基酸评分（AAS）和化学评分（CS）最高的是赖氨酸（Lys）,实验组的必需氨基酸指数（EAAI）均比对照组有所提高.添加2%～3%（w）的螺旋藻对生长性能有显著差异（P〈0.05）,对粗脂肪、粗蛋白的含量有所改善;从肌肉EAAI 来看,添加螺旋藻后的肌肉蛋白质品质优于不添加螺旋藻的对照组.建议饲粮中螺旋藻的添加量为质量分数2%.     

Promotive effect of se on the growth and antioxidation of a blue-green algaSpirulina maxima

Cultures of a blue-green algaSpirulina maxima (Setch. et Gard.) Geitler with various concentrations of Se in Zarrouk's medium showed that not higher than 40 mg/L Se could promote its growth. The present experiments showed thatS. maxima grown under normal conditions, has an oxidant stress defence system for hydrogen peroxide (H₂O₂) removal, which is the Halliwell-Asada pathway. When 4 to 20 mg/L Se was added to the algal medium, this pathway was replaced by a so-called Sestressed pathway containing GSH peroxidase (GSH-POD). As a result of the occurrence of both higher activity of GSH-POD and lower levels of hydroxyl radical (OH·), the Se-stressed pathway scavenged H₂O₂ so effectively that the growth ofS. maxima was promoted by 4 to 20 mg/L Se. While GSH-POD activity of the alga disappeared at 40 mg/L Se, the recovery of ascorbate peroxidase was observed. The lower levels of ascorbic acid and GSH made the Halliwell-Asada pathway for scavenging H₂O₂ less effective, while the highest activity of catalase might be responsible in part for the H₂O₂ removal, causing the level of OH· inS. maxima grown at 40 mg/L Se to be much higher than the OH· level in this alga grown at 4 to 20 mg/L Se, but lower than that in the control. The OH· level changes caused the growth ofS. maxima cultured at 40 mg/L Se to increase slightly to close to that of the control.     

COMBINED EFFECTS OF TEMPERATURE, IRRADIANCE AND SALINITY ON GROWTH OF DIATOM SKELETONEMA COSTATUM

ＩＮＴＲＯＤＵＣＴＩＯＮＶａｒｉｏｕｓｃａｕｓａｔｉｖｅｆａｃｔｏｒｓ,ｓｕｃｈａｓｉｎｃｒｅａｓｅｄｓｃｉｅｎｔｉｆｉｃａｗａｒｅｎｅｓｓ,ｕｔｉｌｉｚａｔｉｏｎｏｆｃｏａｓｔａｌｗａｔｅｒｓｆｏｒａｑｕａｃｕｌｔｕｒｅ,ｅｕｔｒｏｐｈｉｃａｔｉｏｎａｎｄｃｙｓｔｔｒａｎｓｐｏｒｔａｔｉｏｎ (Ｈａｌｌｅｇｒｅａｆｆｅｔａｌ.,1 995)ｈａｓｌｅｄｔｏｅｘｔｅｎｓ ｉｖｅｓｔｕｄｉｅｓｏｎｔｈｅｇｌｏｂａｌｉｎｃｒｅａｓｅｉｎＨＡＢ (ＨａｒｍｆｕｌＡｌｇａｌＢｌｏｏｍ) .ＹｅｔｔｈｅＨＡＢｍｅｃｈａｎｉ…     

螺旋藻制取叶绿素铜钠盐

用乙醇提取螺旋藻中的叶绿素,再用５％ＮａＯＨ溶液皂化、石油醚萃取,在酸性环境中用１０％ＣｕＳＯ４溶液实现铜镁置换,沉淀物经丙配溶解后,加２％ＮａＯＨ的乙醇溶液成盐,过滤,水洗,真空干燥,制成叶绿素铜钠盐．制品的质量达到ＧＢ３２６２－８２的要求．提取率为６４．７％,制品得率占藻粉１．１％。着重对铜镁置换的条件、制品耐酸、耐热、耐光等性能进行了对比试验,结果表明整个工艺是切实可行的．     

虾池中混养江篱是提高对虾产量的重要措施

以生态平衡的观点,综合近几年来海南、湛江、台湾等地虾池中混养江蓠的试验结果,论述了虾池中栽培江蓠对提高对虾产量的重要性,说明了在虾池中混养江蓠是提高对虾产量的有效措施,还提出了江蓠在虾池中起了增氧和清洁水质的作用。     

Bioaccumulation of Pb<Superscript>2+</Superscript> and its effects on growth,morphology and pigment contents of <Emphasis Type="Italic">Spirulina</Emphasis> (<Emphasis Type="Italic">Arthrospira</Emphasis>) <Emphasis Type="Italic">platensis</Emphasis>

A laboratory experiment was conducted to assess the bioaccumulation of Pb²⁺ and its effects on growth, morphology and pigment contents of Spirulina (Arthrospira) platensis. The specimen cultured in Zarrouk liquid medium was treated with various initial metal concentrations (0, 5, 10, 30, 50 and 100 μg mL⁻¹). The growth of S. platensis was adversely affected by Pb²⁺ at high concentrations (30, 50 and 100 μg mL⁻¹). However, at low concentrations (5 μg mL⁻¹), Pb²⁺ could stimulate its growth slightly. The pigment contents (chlorophyll α and β carotene) were decreased in a dose-dependent manner. The highest reductions (67% and 53% respectively in chlorophyll α and β carotene) were observed in 100 μg mL⁻¹ treatment group. The LC₅₀ (96 h) of Pb²⁺ was measured as 75.34 μg mL⁻¹. Apart from a few cases of filament breakages at elevated concentrations (50 and 100 μg mL⁻¹), morphological abnormalities are not specific. Metal bioaccumulation increased with Pb²⁺ concentrations, but decreased with exposure time. The maximum accumulated amount was 188 mg g⁻¹ dry weight. The bioconcentration factor (BCF) reached to a peak at day 2, followed by a gradual reduction for all the exposure concentrations. S. platensis is able to tolerate considerably high Pb²⁺ concentrations. Consequently it can be used as a potential species to remove heavy metal from contaminated waters.     

Isolation,purification and characterization of the hydrogen evolution promoting factor of hydrogenase ofSpirulina platensis

A component (s-factor) with obvious promoting effect on hydrogen evolution of hydrogenase has been isolated and extracted from a cell-free preparation ofSpirulina platensis. The effect of the s-factor in the reaction system is similar to that of Na₂S₂O₄, but is coupled with light. The s-factor has the maximum absorption peak at 620 nm in the oxidized state, at 590 nm in the reduced state. The partially purified s-factor showed two bands by SDS-PAGE and is distinctly different from phycocyanin, which has no change of oxidized state and reduced state absorption spectra, and also has no promoting effect on hydrogenase ofSpirulina platensis under the light. The research supported by the NSFC.     

Isoenzymes and soluble protein in Arthrospirafrom alkaline lakes in Erdos Plateau, China and in exotic species

1 INTRODUCTION Since isoenzyme was first named by Markert and M?ller in 1957 (Hu and Wan, 1985), the separa- tion of isoenzyme has been rapidly developed. Isoenzymes is an important tool for studying life in molecule level. Isoenzymes are transcribed by g…     

Protective effects of C-phycocyanin on alcohol-induced acute liver injury in mice

Excessive alcohol consumption leads to liver disease. Extensive evidence suggests that C-phycocyanin (C-PC), a chromophore phycocyanobilin derived from Spirulina platensis, exerts protective effects against chemical-induced organ damage. In this study, we investigated whether C-PC could protect against ethanol-induced acute liver injury. Serum alanine aminotransferase (ALT), aspartate aminotransferase (AST), triglyceride (TG), total cholesterol (CHOL), low-density lipoprotein (LDL), liver homogenate malondialdehyde (MDA), superoxide dismutase (SOD) content were measured, and pathological examination of liver sections were examined. C-PC showed obvious inhibitory effects on serum ALT, AST, TG, CHOL, LDL and MDA, and SOD content significantly increased in the liver. The structure of hepatic lobules was clear, liver sinus returned to normal, and liver cell cords were arranged in neat rows. Cloudiness, swelling, inflammatory cell infiltration and spotty necrosis of liver cells were significantly reduced. Therefore, C-PC can significantly protect against ethanol-induced acute liver injury.     

The Anti-allergic Activity of Polyphenol Extracted from Five Marine Algae

Natural polyphenol has been widely believed to be effective in allergy remission. Currently, most of the natural polyphenol products come from terrestrial sources such as tea, grape seeds among others, and few polyphenols have been developed from algae for their anti-allergic activity. The aim of the study was to screen some commercial seaweed for natural extracts with anti-allergic activity. Five algae including Laminaria japonica, Porphyra sp., Spirulina platensis, Chlorella pyrenoidosa and Scytosiphon sp. were extracted with ethanol, and the extracts were evaluated for total polyphenol contents and anti-allergic activity with the hyaluronidase inhibition assay. Results showed that the total polyphenol contents in the ethanol extracts ranged from 1.67% to 8.47%, while the highest was found in the extract from Scytosiphon sp. Hyaluronidase inhibition assay showed that the extracts from Scytosiphon sp. had the lowest IC50, 0.67 mg m L-1, while Chlorella pyrenoidosa extract had the highest IC50, 15.07 mg m L-1. The anti-allergic activity of Scytosiphon sp. extract was even higher than the typical anti-allergic drug Disodium Cromoglycate(DSCG)(IC50 = 1.13 mg m L-1), and was similar with natural polyphenol from Epigallocatechin gallate(EGCG)(IC50 = 0.56 mg m L-1). These results indicated that the ethanol extract of Scytosiphon sp. contains a high concentration of polyphenol with high anti-allergic activity. Potentially Scytosiphon sp. can be developed to a natural anti-allergic compound for allergy remission.     

ASPECTS OF IRON NUTRITION IN MACROALGAE ULVA PERTUSA (CHLOROPHYTA) UNDER IRON STRESS

ＩＮＴＲＯＤＵＣＴＩＯＮＩｒｏｎｉｓａｎｉｍｐｏｒｔａｎｔｎｕｔｒｉｔｉｏｎａｌｅｌｅｍｅｎｔｉｎａｌｇａｅｊｕｓｔａｓｉｔｉｓｉｎｈｉｇｈｐｌａｎｔｍｅｔａｂｏｌｉｃｐａｔｈｗａｙｓ.Ｐｈｏｔｏｓｙｎｔｈｅｓｉｓｉｓｄｅｐｅｎｄｅｎｔｏｎｔｈｉｓｅｌｅｍｅｎｔｂｅｃａｕｓｅｃｈｌｏｒｏｐｈｙｌｌｓｙｎｔｈｅｓｉｓｒｅｑｕｉｒｅｓｉｒｏｎｎｕｔｒｉｔｉｏｎ .Ｉｒｏｎｉｓａｌｓｏｅｓｓｅｎｔｉａｌｆｏｒｃｙｔｏｃｈｒｏｍｅｓ,ｆｅｒｒｅｄｏｘｉｎ ,ａｎｄＦｅ ｓｐｒｏｔｅｉｎ .Ｉｔｓｂｉｏｃｈｅｍｉ…     

Isolation of a novel strain of Cyanobacterium sp. with good adaptation to extreme alkalinity and high polysaccharide yield

The use of high alkaline medium is a feasible way to provide carbon source and prevent biological contamination for the outdoor cultivation of alkaliphilic microalgae and cyanobacteria. A novel cyanobacterial strain was isolated from the open pond of a marine green alga( Picochlorum sp. SCSIO-45015, Sanya, Hainan) and identified as Cyanobacterium sp. SCSIO-45682. The effects of initial sodium bicarbonate(NaHCO_3) concentrations on the growth and biochemical composition of Cyanobacterium sp. SCSIO-45682 were investigated. The results demonstrated that Cyanobacterium sp. SCSIO-45682 had good adaptation to 16.8-g/L NaHCO_3(the same concentration of NaHCO_3 used in Zarrouk medium for Spirulina). Moreover, the yields of biomass, polysaccharide, chlorophyll a(chl a), and phycocyanin increased under high NaHCO_3 concentrations. The maximum final biomass concentration of 2.5 g/L was observed at 8.4-g/L NaHCO_3, while the highest intracellular total saccharide content of 49.2% of dry weight(DW) and exopolysaccharide(EPS) concentration of 93 mg/L were achieved at the NaHCO_3 concentration of 16.8 g/L. The crude protein content declined under high NaHCO_3 concentrations, which provide a possible explanation for the accumulation of polysaccharide. This study shows a good potential of alkaliphilic Cyanobacterium sp. SCSIO-45682 as a polysaccharide feedstock.     

Temperature Influences on the Expression of GFP Promoted by the Upstream Sequence of cpcB from Arthrospiraplatensis

In order to investigate the regulation mechanism of the phycocyanin gene,a series of functional analyses of the upstream sequence of cpcB gene from Arthrospira platensis were conducted in E. coli with green fluorescent protein encoding gene(gfp) as the reporter. Results showed that the gfp gene could express at a high level under the promotion of the upstream sequence,suggesting the existence of some strong promoter elements in it. The expression of GFP was influenced by temperature. Higher temperature led to higher expression level. The bioinformatics analyses followed by mutation analyses on the secondary structure of translation ini-tiation region(TIR) revealed that RNA thermosensor might account for the temperature regulation.     

Heavy metals in sediments of Yellow Sea and East China Sea: Chemical speciation,distribution, infl uence factor,and contamination

Metal species and the degree of environmental pollution are related to the hydrogen sulfi de(H 2 S), an important product of early diagenesis that can react with metals to form stable compounds. To investigate the eff ects of H 2 S to metals and evaluate metal environment eff ect in the sediments of the East China Sea(ECS) and Yellow Sea(YS), geochemical characteristic and spatial distribution of nine heavy metals and H 2 S profi le were studied. Higher H 2 S content and lower metal content was observed in the sediments 10 cm in depth in the North Yellow Sea and the west coast of South Korea. The pollution load index( I pl) indicates that the southern coast of Shandong Peninsula underwent moderate pollution( I pl =1) of heavy metals and no heavy metal pollution appeared in other areas( I pl 1). To some extents, the ecological risk of Cd and As enrichment was moderately severe in all stations. The chance of heavy metal combination to be toxic in ECS and YS during summer was 21%. In addition, correlation between H 2 S content and metals in both solid and porewater phases was obvious, corroborating important eff ect of H 2 S on metal distribution. Moreover, H 2 S could aff ect the spatial distributions of heavy metals in porewater directly and be indicative of potential biological eff ects of combined toxicant groups in the study region.     

壳聚糖对腐生葡萄球菌的作用机制

【目的】探究壳聚糖处理对腐生葡萄球菌(Staphylococcus saprophytic)的作用机制。【方法】通过光密度值结合菌液澄清度法综合确定壳聚糖对腐生葡萄球菌的最小抑菌浓度(Minimum Inhibitory Concentration,MIC),分析其在MIC与2MIC的壳聚糖作用下的微生物生长曲线、电导率值、碱性磷酸酶(Alkaline Phosphatase,AKP)含量、过氧化氢酶(Catalase,CAT)含量、苹果酸脱氢酶(Malatedehydrogenase,MDH)含量与生物膜生成量等指标变化,并结合扫描电镜(ScanningElectronMicroscopy,SEM)观察其作用后对菌体细胞形态变化影响,综合评价壳聚糖处理对腐生葡萄球菌的作用机制。【结果与结论】壳聚糖对腐生葡萄球菌的MIC为1.25 mg/mL;菌体经MIC和2MIC处理后,其正常生长受到抑制,细胞壁被破坏,细胞膜通透性改变,CAT与MDH含量降低,其作用效果与壳聚糖浓度正相关;SEM结果显示,与对照CK组对比,腐生葡萄球菌经MIC壳聚糖处理后,菌体形状不规则,表面皱褶;经2MIC壳聚糖处理后,菌体表面产生泡状物且黏附明显,表明壳聚糖使腐生葡萄球菌菌体细胞壁受损,菌体生长受到抑制,胞内保护酶与三羧酸循环中的关键酶活性降低,细胞代谢能力随之下降,细胞膜结构完整度受到破坏,最终导致菌体死亡。