[Objective] This study aimed to gain better understanding of the effects of salt stress on photosynthesis of Spirulina platensis. [Method] A salt stress simulation experiment was carried out, in which Spirulina platen...[Objective] This study aimed to gain better understanding of the effects of salt stress on photosynthesis of Spirulina platensis. [Method] A salt stress simulation experiment was carried out, in which Spirulina platensis cells were incubated with different salt concentrations （0, 0.1, 0.3, 0.5, 0.8, and 1.0 mol/L of NaCI）. Subsequently, some photosynthesis-related parameters were determined after incubated at various NaCI concentrations for 24 h. [Result] Under our experimental conditions, chlorophyll, carotenoid, phycocyanin and allophycocyanin contents, and photosynthesis rate decreased with the increasing NaCI concentrations. Above the 0.5 mol/L Na- CI level, the detrimental effect of salt stress became more severe. [Conclusion] From the results obtained in this investigation, we can conclude that the decrease in chlorophyll, carotenoid, phycocyanin and allophycocyanin contents may be the most important reason causing the decline in photosynthsis rate which strongly affects the biomass yield of Spirulina platensis in outdoor cultivation展开更多
Ulcerative colitis(UC)is a chronic and recurrent inflammatory bowel disease(IBD)that has become a major gastroenterologic problem during recent decades.Numerous complicating factors are involved in UC development such...Ulcerative colitis(UC)is a chronic and recurrent inflammatory bowel disease(IBD)that has become a major gastroenterologic problem during recent decades.Numerous complicating factors are involved in UC development such as oxidative stress,inflammation,and microbiota disorder.These factors exacerbate damage to the intestinal mucosal barrier.Spirulina platensis is a commercial alga with various biological activity that is widely used as a functional ingredient in food and beverage products.However,there have been few studies on the treatment of UC using S.platensis aqueous extracts(SP),and the underlying mechanism of action of SP against UC has not yet been elucidated.Herein,we aimed to investigate the modulatory effect of SP on microbiota disorders in UC mice and clarify the underlying mechanisms by which SP alleviates damage to the intestinal mucosal barrier.Dextran sulfate sodium(DSS)was used to establish a normal human colonic epithelial cell(NCM460)injury model and UC animal model.The mitochondrial membrane potential assay 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide(MTT)and staining with Annexin V-fluorescein isothiocyanate(FITC)/propidium iodide(PI)and Hoechst 33258 were carried out to determine the effects of SP on the NCM460 cell injury model.Moreover,hematoxylin and eosin(H&E)staining,transmission electron microscopy(TEM),enzyme-linked immunosorbent assay(ELISA),quantitative real-time polymerase chain reaction(qPCR),western blot,and 16S ribosomal DNA(rDNA)sequencing were used to explore the effects and underlying mechanisms of action of SP on UC in C57BL/6 mice.In vitro studies showed that SP alleviated DSS-induced NCM460 cell injury.SP also significantly reduced the excessive generation of intracellular reactive oxygen species(ROS)and prevented mitochondrial membrane potential reduction after DSS challenge.In vivo studies indicated that SP administration could alleviate the severity of DSS-induced colonic mucosal damage compared with the control group.Inhibition of inflammation and oxidative stress was associated with increases in the activity of antioxidant enzymes and the expression of tight junction proteins(TJs)post-SP treatment.SP improved gut microbiota disorder mainly by increasing antioxidant enzyme activity and the expression of TJs in the colon.Our findings demonstrate that the protective effect of SP against UC is based on its inhibition of pro-inflammatory cytokine overproduction,inhibition of DSS-induced ROS production,and enhanced expression of antioxidant enzymes and TJs in the colonic mucosal barrier.展开更多
AIM: To compare the therapeutic effects of polysaccharide extract from Spirulina platensis (PSP) and extract from amnion membrane CAME) on alkali burn-induced corneal neovascularization (CorNV). METHODS: PSP and AME w...AIM: To compare the therapeutic effects of polysaccharide extract from Spirulina platensis (PSP) and extract from amnion membrane CAME) on alkali burn-induced corneal neovascularization (CorNV). METHODS: PSP and AME were Extracted from dry powder of Spirulina platensis and human aminion membrane respectively. Murine CorNV was induced by applying 1N sodiumhydroxide (NaOH) solution directly on the mice corneas. PSP and AME extracts were administered topically on the corneas 4 times daily for 7 days. The therapy effects of PSP and AME extracts were evaluated daily using slit-lamp. At the end of the therapy, corneas were harvested for H&E staining, masson trichrome staining, immunohistochemical study, and semi-quantification reverse transcriptive PCR (RT-PCR) was utilized for measurement of inflammation-related molecules. RESULTS: Topical application of PSP extract had significant therapeutic effects on CorNV that could be shown in various assays of the corneas. Compared with AME Extract, PSP extract treatment was more effective in suppressing CorNV in berms of vessel length and levels of cluster of differentiation 31 (CD31) proteins or the angiogenesis related genes like vascular endothelial growth factor (VEGF), matrix metalloproteinase-2 (MMP2) and matrix metalloproteinase-9 (MMP9). PSP also inhibited inflammation more markedly by more effectively inhibiting mononuclear and polymorphonuclear cells infiltration into the corneal stroma and reducing levels of stromal cell-derived factor-1 (SDF1), tumor necrosis factor-alpha (TNF alpha) and macrophage inflammatory protein-3 (MIP3a). In addition, corneas of PSP group had a more regular and compact architecture of collagen with thinner corneal thickness than in the AME group. ' CONCLUSION: Polysaccharide extract from Spirulina platensis inhibited alkali burn-induced inflammation and CorNV more effectively than AME Extract at the studied doses, thus may be used for the therapy of corneal diseases involving neovascularization and inflammation.展开更多
The present study aimed to determine whether a polysaccharide obtained fromSpirulina platensis shows protective effects on dopaminergic neurons. A Parkinson’s disease model was established through the intraperitoneal...The present study aimed to determine whether a polysaccharide obtained fromSpirulina platensis shows protective effects on dopaminergic neurons. A Parkinson’s disease model was established through the intraperitoneal injection of 1-methyl-4-phenyl-1,2,3,6-tetrahydropyr-idine （MPTP） in C57BL/6J mice. Prior to the MPTP injection, some mice were pretreated with intraperitoneal injections of a polysaccharide derived fromSpirulina platensis once daily for 10 days. The results showed that the immunoreactive staining and mRNA expression of the dopa-mine transporter and tyrosine hydroxylase, the rate-limiting enzyme in dopamine synthesis, in the substantia nigra, were signiifcantly increased in mice pretreated with 800 mg/kg of the poly-saccharide compared with those in MPTP-treated mice. The activities of superoxide dismutase and glutathione peroxidase in the serum and midbrain were also increased signiifcantly in mice injected with MPTP after pretreatment with the polysaccharide fromSpirulina platensis. By con-trast, the activity of monoamine oxidase B in serum and midbrain maintained unchanged. These experimental ifndings indicate that the polysaccharide obtained fromSpirulina platensis plays a protective role against the MPTP-induced loss of dopaminergic neurons in C57BL/6J mice, and that the antioxidative properties of this polysaccharide likely underlie its neuroprotective effect.展开更多
Alternative protein sources, such as insects or algae meals are in special focus of animal nutrition in order to replace soybean meal (SBM). As part of the multidisciplinary project “sustainability transitions” this...Alternative protein sources, such as insects or algae meals are in special focus of animal nutrition in order to replace soybean meal (SBM). As part of the multidisciplinary project “sustainability transitions” this study evaluated effects of replacing SBM by partly defatted larvae meal from the black soldier fly, Hermetia illucens or meal from the micro algae Spirulina platensis in broiler diets. The aim of the current study was to investigate the chickens’ growth performance and the intestinal morphology as well as the health status. 288 one-day-old male growing chickens (Ross 308) from a commercial hatchery were randomly allotted to 48 pens (6 birds per pen) for the growth study with five diets and feed supply on free choice level. The control diet was based on wheat, corn and SBM. The experimental diets replaced 50% of SBM by the alternative proteins under study, both on a basic level of amino acid (AA) supplementation (Lys and Met added equal to the control diet) (diet HM and SM) and an extended level of AA fortification (Lys, Met, Thr, Arg, Val added) (diet HM+ and SM+). Response of chickens was evaluated by zoo-technical parameters, which were under weekly control (e.g. growth, feed intake, feed conversion ratio, mortality). After finishing the growth study birds from control and the experimental diets at the basic level of AA supplementation were slaughtered after 12 hour fastening and utilized for gut morphometric analysis and histological evaluation of the health status. Diets at a basic level of AA fortification led to significant depression of growth, feed intake, feed conversion ratio, and protein conversion ratio, respectively. In addition, the acceptance of the Spirulina diet was lower (p ≤ 0.001) as compared to the Hermetia based diet. However, the extended level of AA supplementation improved all parameters significantly. Diets without extended AA supply altered some morphological parameters of the intestinal wall, but the nutritional significance of this observation needs to be verified in AA balanced diets. The health state of chicken was not impaired by the diets under study.展开更多
CCC plasmid was isolated from an economically important blue-green alga- Spirulina platensis (1.7×106 dalton from the S6 strain and 1.2×106 dalton from the F, strain) using a rapid method based on ultrasonic...CCC plasmid was isolated from an economically important blue-green alga- Spirulina platensis (1.7×106 dalton from the S6 strain and 1.2×106 dalton from the F, strain) using a rapid method based on ultrasonic disruption of algal cells and alkaline removal of chromosomal DNA. The difference in the molecular weight of the OOC DNAs from the two strains differing in form suggests that plasmid may be related with the differentiation of algal form. This modified method, which does not use any lysozyme, is a quick and effective method of plasmid isolation, especially for filamentous blue-green algae.展开更多
Attempts were made to culture Spirulina platensis in human urine directly to achieve biomass production and O2 evolution, for potential application to nutrient regeneration and air revitalization in life support syste...Attempts were made to culture Spirulina platensis in human urine directly to achieve biomass production and O2 evolution, for potential application to nutrient regeneration and air revitalization in life support system. The culture results showed that Spirulinaplatensis grows successfully in diluted human urine, and yields maximal biomass at urine dilution ratios of 140-240. Accumulation of lipid and decreasing of protein occurred due to N deficiency. O2 release rate of Spirulina platensis in diluted human urine was higher than that in Zarrouk medium.展开更多
The growth of Arthrospira platensis and physiological changes in biomass under the effects of six rare earth elements Dy,Sm,Tb,La,Nd and Yb were evaluated.Elements were tested by three concentrations of 10,20 and 30 m...The growth of Arthrospira platensis and physiological changes in biomass under the effects of six rare earth elements Dy,Sm,Tb,La,Nd and Yb were evaluated.Elements were tested by three concentrations of 10,20 and 30 mg/L.According to neutron activation analysis data A.platensis’s accumulation capacity toward studied elements changes in the following order of La>Dy>Nd>Sm>Yb>Tb.The results show that Dy and La ions stimulate biomass growth and Yb ions inhibit it,while Sm,Tb and Nd ions do not affect biomass accumulation.The contents of proteins and chlorophyll a are not affected by the presence of rare earth elements in the cultivation medium.Studied elements affect to different extents carbohydrates,phycobilins,β-carotene,lipids and MDA contents in spirulina biomass.Changes in the antioxidant activity under applied metal loads reveal a moderate stress in exposed A.platensis.Cyanobacterium A.platensis can be successfully used for bioremediation of natural water contaminated with REEs as well as REEs recovery from low polluted industrial effluents.展开更多
Culture ofArthrospiraplatensis （Spirulinaplatens） in human urine was investigated to get valuable biomass. NO3-N was the proper N source, in comparison with other N source, including urea, NH4-N and NO2-N. As a resu...Culture ofArthrospiraplatensis （Spirulinaplatens） in human urine was investigated to get valuable biomass. NO3-N was the proper N source, in comparison with other N source, including urea, NH4-N and NO2-N. As a result, aerobic nitrification of human urine was performed, with above 93.6% nitrification percentage finally achieved with total-N （TN） load of 46.52 mg/（L.d）, in which Arthrospira platensis was successfully grown. The main compositions of the obtained biomass are close to those in Zarrouk medium. Thus, it is possible to culture Arthrospiraplatensis in nitrified human urine for food production within bioregenerative life support systems （BLSSs）.展开更多
Arsenic-contaminated water is a serious hazard for human health. Plankton plays a critical role in the fate and toxicity of arsenic in water by accumulation and biotransformation.Spirulina platensis（S. platensis）, a...Arsenic-contaminated water is a serious hazard for human health. Plankton plays a critical role in the fate and toxicity of arsenic in water by accumulation and biotransformation.Spirulina platensis（S. platensis）, a typical plankton, is often used as a supplement or feed for pharmacy and aquiculture, and may introduce arsenic into the food chain, resulting in a risk to human health. However, there are few studies about how S. platensis biotransforms arsenic. In this study, we investigated arsenic biotransformation by S. platensis. When exposed to arsenite（As（Ⅲ））, S. platensis accumulated arsenic up to 4.1 mg/kg dry weight.After exposure to As（Ⅲ）, arsenate（As（Ⅴ）） was the predominant species making up 64% to86% of the total arsenic. Monomethylarsenate（MMA（Ⅴ）） and dimethylarsenate（DMA（Ⅴ））were also detected. An arsenite S-adenosylmethionine methyltransferase from S. platensis（Sp Ars M） was identified and characterized. Sp Ars M showed low identity with other reported Ars M enzymes. The Escherichia coli AW3110 bearing Spars M gene resulted in As（Ⅲ） methylation and conferring resistance to As（Ⅲ）. The in vitro assay showed that Sp Ars M exhibited As（Ⅲ） methylation activity. DMA（Ⅴ） and a small amount of MMA（Ⅴ） were detected in the reaction system within 0.5 hr. A truncated Sp Ars M derivative lacking the last 34 residues still had the ability to methylate As（Ⅲ）. The three single mutants of Sp Ars M（C59S, C186 S, and C238S） abolished the capability of As（Ⅲ） methylation, suggesting the three cysteine residues are involved in catalysis. We propose that Sp Ars M is responsible for As methylation and detoxification of As（Ⅲ） and may contribute to As biogeochemistry.展开更多
In the present study,an oligosaccharide SPO-1 from Spirulina platensis was prepared by glycosidase from a marine bacterium.The prebiotic activity of SPO-1 on the growth of Lactobacillus paracasei and Bifidobacterium a...In the present study,an oligosaccharide SPO-1 from Spirulina platensis was prepared by glycosidase from a marine bacterium.The prebiotic activity of SPO-1 on the growth of Lactobacillus paracasei and Bifidobacterium animalis,and its effect on human gut microbiota were examined in vitro.The molecular weight of the tetrasaccharide SPO-1 was 650.2 Da,and it was mainly composed of glucose with α-type glycosidic linkages.The prebiotic activity score of SPO-1 was the highest for the growth of probiotic strains L.paracasei and B.animalis.Furthermore,as fermentation proceeded,SPO-1 was gradually degraded and utilized by intestinal bacteria.The results showed that after treatment with SPO-1,carbohydrate consumption and short-chain fatty acids levels were increased,especially those of i-butyric and i-valeric acids.Moreover,SPO-1 significantly promoted the abundance,diversity and composition of gut microbiota,especially stimulating the growth of Bacteroides,Escherichia-Shigella and Megamonas.In addition,the change in intestinal microbiota function predicted by phylogenetic investigation of communities by reconstruction of unobserved states(PICRUSt)after treatment with SPO-1 is mainly related to the terms“carbohydrate metabolism”and“amino acid metabolism”.These results suggest that SPO-1 is a potential oligosaccharide in regulation of intestinal microbiota.展开更多
In this paper we report that CeCl3 could accelerate the synthesis of chlorophyll a and protein in spirulina platensis. and enhance the activity of oxygen evolution. We also found that the accelerations of CeCl3 in spi...In this paper we report that CeCl3 could accelerate the synthesis of chlorophyll a and protein in spirulina platensis. and enhance the activity of oxygen evolution. We also found that the accelerations of CeCl3 in spirulina platensis culture solution of low NaHCO3 were more than in culture solution of high NaHCO3, therefore it was related to the concentration of NaHCO3 The absorption spectrum and low temperature (77 K) fluorescence emission spectrum of spirulina platensis with CeCl3 treated were significantly different from their controls,i.e.its absorption peak of phycocyanin at 620 nm was higher than that of the control.its absorption peak at the long wave region migrated from 676 to 680 nm, and its fluorecence emission ratios (730 nm/685～695 nm) of photosystem I(PSI) to photosystem Ⅱ(PS Ⅱ) were also higher than those of the control; the pitch of the spiral algal body became shorter, and induced structural changes too.展开更多
A laboratory experiment was conducted to assess the bioaccumulation of Pb^2＋ and its effects on growth, morphology and pigment contents of Spirulina （Arthrosl）ira）platensis. The specimen cultured in Zarrouk liquid...A laboratory experiment was conducted to assess the bioaccumulation of Pb^2＋ and its effects on growth, morphology and pigment contents of Spirulina （Arthrosl）ira）platensis. The specimen cultured in Zarrouk liquid medium was treated with various initial metal concentrations （0, 5, 10, 30, 50 and 10μgmL^-1）. The growth ofS. platensis was adversely affected by Pb〉 at high concentrations （30, 50 and 100μgmL^-1）. However, at low concentrations （5μgmL^-1）, Pb^2＋ could stimulate its growth slightly. The pigment contents （chlorophyllα and β carotene） were decreased in a dose-dependent manner. The highest reductions （67% and 53% respectively in chlorophyll α andβ carotene） were observed in 100 μg mL^-1 treatment group. The LC50 （96 h） of Pb^2- was measured as 75.34 μg mL^-1. Apart from a few cases of filament breakages at elevated concentrations （50 and 100 μgmL^-1）, morphological abnormalities are not specific. Metal bioaccumulation increased with Pb^2- concentrations, but decreased with exposure time. The maximum accumulated amount was 188 mgg^-1 dry weight. The bioconcentration factor （BCF） reached to a peak at day 2, followed by a gradual reduction tbr all the exposure concentrations. S. platensis is able to tolerate considerably high Pb^2＋ concentrations. Consequently it can be used as a potential species to remove heavy metal from contaminated waters.展开更多
An original bi-enzymatic biosensor was designed by immobilizing Arthrospira platensis cells, called Spirulina, on gold interdigitated transducers. Phosphatase and esterase activities were inhibited, respectively, by h...An original bi-enzymatic biosensor was designed by immobilizing Arthrospira platensis cells, called Spirulina, on gold interdigitated transducers. Phosphatase and esterase activities were inhibited, respectively, by heavy metals and by pesticides. Inhibition activities were observed with different mixtures of pesticides + heavy metals. The quantification limits for Cd2+ and Hg2+ are 10-20 M in mixture and in pure solution. The quantification limits of parathion-methyl, paraoxon-methyl and triazine are respectively 10-20 M, 10-18 M and 10-20 M in mixture and pure solutions. These results show that there is no synergistic effect between the two families of pollutants. Qualitative contamination of effluent samples and their purification after passing through a municipal wastewater treatment plant were observed by our bi-enzymatic biosensor and confirmed by classical analytical techniques for heavy metal ions.展开更多
The objective of this study was to measure protein quality parameters (PPV, NPU and NPUstd) of chicken diets with complete substitution of soybean meal (SBM) by Spirulina meal (SM) or partly defatted Hermetia meal (HM...The objective of this study was to measure protein quality parameters (PPV, NPU and NPUstd) of chicken diets with complete substitution of soybean meal (SBM) by Spirulina meal (SM) or partly defatted Hermetia meal (HM). N balance experiments were based on the quantitative excreta collection method, divided into starter period (10 - 20 d) and grower period (25 - 35 d). The study utilized 70 all male meat type chicken (Ross 308). Data assessment applied the exponential N utilization model of the “Goettingen approach”. The control diet was based on wheat, corn and SBM. In four experimental diets SBM was completely substituted by SM or HM, but fortified with feed amino acids (AA) both on a basic level of supplementation (Lys and Met added equal to the control diet) and on an extended level (Lys, Met, Thr, Arg, Val, Ile, His added). At a basic level of AA supplementation, complete replacement of SBM by SM or HM in chicken diets depressed dietary protein quality significantly (p 0.05). However, the extended level of AA supplementation improved protein quality parameters of the diets with both of the alternative proteins significantly (p < 0.05), but still generally not on par with the control diet. The observed responses were accentuated when the well-known effect of N intake on protein utilization was eliminated through the standardization of N intake by application of the “Goettingen approach”.展开更多
Trace elements or micronutrients play a major role in the metabolism of both plants and humans. Zinc has a major specific role in metabolism when compared with other elements. The microbial biofertilizers are applied ...Trace elements or micronutrients play a major role in the metabolism of both plants and humans. Zinc has a major specific role in metabolism when compared with other elements. The microbial biofertilizers are applied in the form of seaweed liquid extracts, microbial inoculants, biostimulators and biofortification agents. All these categories of microbial biofertilizers are involved in the enhancement of plant nutrient uptake. In the present study, Spirulina platensis is used as a biofortification agent to enhance zinc levels in cultivars of Amaranthus gangeticus, Phaseolus aureus and Tomato. Different experimental methods were followed including soaking seeds in different concentrations of Spirulina (5, 10, 15, 20, 25 and 30 g in 100 ml of water);soaking seeds in Spirulina hydrolysate at different time intervals (1, 2, 3, 4, 5 hrs and overnight);Spirulina in combination with biofertilizers, chemical fertilizer, organic fertilizer and vermicompost in various proportions (25:75;50:50;75:25) and foliar spray with different concentrations of Spirulina (25, 50, 75, and 100g in 5 litres of water) respectively. The zinc content of the yield of the cultivars was estimated and the study results indicated that there was a significant increase in zinc levels with p-value 0.015, 0.003 and 0.035 for Amaranthus gangeticus, Phaseolus aureus and Tomato respectively when compared with the control and between the set-ups, with biofortification of Spirulina platensis. The obtained results emphasize the application of Spirulina platensis to enhance the mineral nutrient in plants which are non-polluting, inexpensive, utilizable renewable resource to maintain the soil fertility.展开更多
This study was conducted to evaluate the use of cyanobacteria Arthrospira platensis and cladoceran Daphnia magna biomass as complementary protein and lipid sources in diet supplementation for common carp (Cyprinus car...This study was conducted to evaluate the use of cyanobacteria Arthrospira platensis and cladoceran Daphnia magna biomass as complementary protein and lipid sources in diet supplementation for common carp (Cyprinus carpio L.) nursery. Three experimental diets containing A. platensis and D. magna meal at different concentrations were compared to the commercial (control) diet. Each experimental diet (ED) was set to contain D. magna and A. platensis meal at a specific combination: 2% and 5%, 2% and 7%, and 4% and 5% for ED1, ED2 and ED3, respectively. The protein and lipid content of the experimental diets ranged from 43.20% to 44.60% dry weight (DW) and 10.64% to 13.42% DW, respectively;while the protein and lipid content of the control diet were 43.00% DW and 6.72% DW, respectively. After 20 days of feeding period, ED3 group obtained the highest final body weight (BW) (58.18 ± 35.24 mg), total biomass (1936 ± 1625 mg), food conversion rate (1.34 ± 0.04), and specific growth rate (12.86 ± 0.03% BW day<sup>–1</sup>) among all treatment groups (P > 0.05);while ED1 group obtained the highest survival (75.5% ± 7.47%) among all treatment groups (P > 0.05). The total bacterial count and total pathogenic Aeromonas sp. in the culture water of the treatment groups (ranged from 2.00 to 2.65 × 10<sup>5 </sup>CFU mL<sup>–1</sup> and 3.50 to 4.12 × 10<sup>3</sup> CFU mL<sup>–1</sup>, respectively) were lower compared to the water of the control group fed (3.73 × 10<sup>5</sup> and 4.70 × 10<sup>3</sup> CFU mL<sup>–1</sup>, respectively). No significant differences in physicochemical water quality parameters were observed among treatments (P > 0.05). The current study suggests that the combination of A. platensis and D. magna biomass can be used as complementary protein and lipid sources in diet supplementation for common carp larvae and can result in a comparable fish growth, survival and feed utilization in common carp culture at the nursery phase.展开更多
Objective: To investigate the ef ect of intra-peritoneal injection of purii ed exudates of axenic Spirulina platensis on the mammalian endocrine and nervous systems. Methods: The intra-peritoneal injection of the cyan...Objective: To investigate the ef ect of intra-peritoneal injection of purii ed exudates of axenic Spirulina platensis on the mammalian endocrine and nervous systems. Methods: The intra-peritoneal injection of the cyanobacterial exudates in mice was applied. Sex hormonal levels of testosterone and progesterone were measured using radioimmunoassay while the follicular stimulating hormone and luteinizing hormone were evaluated by direct chemiluminescence. In addition, superoxide dismutase, catalase and glutathione peroxidase were monitored in the hippocampus region using spectrophotometric method. The levels of the hippocampal monoamines, dopamine, noradrenaline and serotonin were analyzed by high performance liquid chromatography while the acetyl choline neurotransmitter was measured by colorimetric method using choline/acetylcholine assay kit. Results: A sharp disruption in the sex hormones levels of testosterone, progesterone, follicular stimulating hormone and luteinizing hormone was demonstrated in the serum of the treated mice. At the same time, a signii cant reduction in the endogenous antioxidant defense enzymes, superoxide dismutase, catalase and glutathione peroxidase was observed in the hippocampus region of the injected mice. Moreover, levels of dopamine, noradrenaline, serotonin and acetyl choline neurotransmitter in the same region were signii cantly af ected as a result of the treatment with Spirulina i ltrate. The gas chromatography-mass spectrometer and liquid chromatography mass spectrometry/mass spectrometry analysis showed the presence of some sterol-like compounds in the cyanobacterial i ltrate. Conclusions: This study demonstrated the capability of Spirulina to release detrimental bioactive metabolites into their surrounding that can disrupt the mammalian endocrine and nervous systems.展开更多
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-actio...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<sub>2</sub>S<sub>2</sub>O<sub>4</sub>, 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.展开更多
This study on the effect of different concentrations of germanium dioxide （GeO<sub>2</sub>） on the specificgrowth rate （SGR）, pigment contents, protein content and amino acid composition of Spirulina p...This study on the effect of different concentrations of germanium dioxide （GeO<sub>2</sub>） on the specificgrowth rate （SGR）, pigment contents, protein content and amino acid composition of Spirulina platensisshowed that Ge was not the essential element of this alga; that GeO<sub>2</sub> could speed up growth and raiseprotein content of S. platensis, and could possibly influence the photosynthesis system. The concentrationrange of GeO<sub>2</sub> beneficial to growth of S. platensis is from 5-100 mg/l. GeO<sub>2</sub> is proposed to be util-ized to remove contamination by Chlorella spp. usually occurring in the cultivation of Spirulina.展开更多
基金Supported by Project of Applied Basic Research from Sichuan Provincial Department of Science and Technology(2009JY0144)~~
文摘[Objective] This study aimed to gain better understanding of the effects of salt stress on photosynthesis of Spirulina platensis. [Method] A salt stress simulation experiment was carried out, in which Spirulina platensis cells were incubated with different salt concentrations （0, 0.1, 0.3, 0.5, 0.8, and 1.0 mol/L of NaCI）. Subsequently, some photosynthesis-related parameters were determined after incubated at various NaCI concentrations for 24 h. [Result] Under our experimental conditions, chlorophyll, carotenoid, phycocyanin and allophycocyanin contents, and photosynthesis rate decreased with the increasing NaCI concentrations. Above the 0.5 mol/L Na- CI level, the detrimental effect of salt stress became more severe. [Conclusion] From the results obtained in this investigation, we can conclude that the decrease in chlorophyll, carotenoid, phycocyanin and allophycocyanin contents may be the most important reason causing the decline in photosynthsis rate which strongly affects the biomass yield of Spirulina platensis in outdoor cultivation
基金the National Key R&D Program of China(No.2018YFC1603900)the National Natural Science Foundation of China(Nos.32070509 and 31501894)the Guangdong Basic and Applied Basic Research Foundation(No.2021A1515220119),China。
文摘Ulcerative colitis(UC)is a chronic and recurrent inflammatory bowel disease(IBD)that has become a major gastroenterologic problem during recent decades.Numerous complicating factors are involved in UC development such as oxidative stress,inflammation,and microbiota disorder.These factors exacerbate damage to the intestinal mucosal barrier.Spirulina platensis is a commercial alga with various biological activity that is widely used as a functional ingredient in food and beverage products.However,there have been few studies on the treatment of UC using S.platensis aqueous extracts(SP),and the underlying mechanism of action of SP against UC has not yet been elucidated.Herein,we aimed to investigate the modulatory effect of SP on microbiota disorders in UC mice and clarify the underlying mechanisms by which SP alleviates damage to the intestinal mucosal barrier.Dextran sulfate sodium(DSS)was used to establish a normal human colonic epithelial cell(NCM460)injury model and UC animal model.The mitochondrial membrane potential assay 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide(MTT)and staining with Annexin V-fluorescein isothiocyanate(FITC)/propidium iodide(PI)and Hoechst 33258 were carried out to determine the effects of SP on the NCM460 cell injury model.Moreover,hematoxylin and eosin(H&E)staining,transmission electron microscopy(TEM),enzyme-linked immunosorbent assay(ELISA),quantitative real-time polymerase chain reaction(qPCR),western blot,and 16S ribosomal DNA(rDNA)sequencing were used to explore the effects and underlying mechanisms of action of SP on UC in C57BL/6 mice.In vitro studies showed that SP alleviated DSS-induced NCM460 cell injury.SP also significantly reduced the excessive generation of intracellular reactive oxygen species(ROS)and prevented mitochondrial membrane potential reduction after DSS challenge.In vivo studies indicated that SP administration could alleviate the severity of DSS-induced colonic mucosal damage compared with the control group.Inhibition of inflammation and oxidative stress was associated with increases in the activity of antioxidant enzymes and the expression of tight junction proteins(TJs)post-SP treatment.SP improved gut microbiota disorder mainly by increasing antioxidant enzyme activity and the expression of TJs in the colon.Our findings demonstrate that the protective effect of SP against UC is based on its inhibition of pro-inflammatory cytokine overproduction,inhibition of DSS-induced ROS production,and enhanced expression of antioxidant enzymes and TJs in the colonic mucosal barrier.
基金Supported by Natural Science Foundation of Shandong Province of China for Distinguished Young Scholars under Grant(No.JQ200908)Shandong Province Natural Science Foundation,China(No.Q2008C02)Yiqiang Wang is partially supported by Shandong Taishan Scholar Program(QDU-EYE)
文摘AIM: To compare the therapeutic effects of polysaccharide extract from Spirulina platensis (PSP) and extract from amnion membrane CAME) on alkali burn-induced corneal neovascularization (CorNV). METHODS: PSP and AME were Extracted from dry powder of Spirulina platensis and human aminion membrane respectively. Murine CorNV was induced by applying 1N sodiumhydroxide (NaOH) solution directly on the mice corneas. PSP and AME extracts were administered topically on the corneas 4 times daily for 7 days. The therapy effects of PSP and AME extracts were evaluated daily using slit-lamp. At the end of the therapy, corneas were harvested for H&E staining, masson trichrome staining, immunohistochemical study, and semi-quantification reverse transcriptive PCR (RT-PCR) was utilized for measurement of inflammation-related molecules. RESULTS: Topical application of PSP extract had significant therapeutic effects on CorNV that could be shown in various assays of the corneas. Compared with AME Extract, PSP extract treatment was more effective in suppressing CorNV in berms of vessel length and levels of cluster of differentiation 31 (CD31) proteins or the angiogenesis related genes like vascular endothelial growth factor (VEGF), matrix metalloproteinase-2 (MMP2) and matrix metalloproteinase-9 (MMP9). PSP also inhibited inflammation more markedly by more effectively inhibiting mononuclear and polymorphonuclear cells infiltration into the corneal stroma and reducing levels of stromal cell-derived factor-1 (SDF1), tumor necrosis factor-alpha (TNF alpha) and macrophage inflammatory protein-3 (MIP3a). In addition, corneas of PSP group had a more regular and compact architecture of collagen with thinner corneal thickness than in the AME group. ' CONCLUSION: Polysaccharide extract from Spirulina platensis inhibited alkali burn-induced inflammation and CorNV more effectively than AME Extract at the studied doses, thus may be used for the therapy of corneal diseases involving neovascularization and inflammation.
基金financially supported by grants from the Natural Science Foundation of Shandong Province of China,No.ZR2011HQ008,ZR2011HM044
文摘The present study aimed to determine whether a polysaccharide obtained fromSpirulina platensis shows protective effects on dopaminergic neurons. A Parkinson’s disease model was established through the intraperitoneal injection of 1-methyl-4-phenyl-1,2,3,6-tetrahydropyr-idine （MPTP） in C57BL/6J mice. Prior to the MPTP injection, some mice were pretreated with intraperitoneal injections of a polysaccharide derived fromSpirulina platensis once daily for 10 days. The results showed that the immunoreactive staining and mRNA expression of the dopa-mine transporter and tyrosine hydroxylase, the rate-limiting enzyme in dopamine synthesis, in the substantia nigra, were signiifcantly increased in mice pretreated with 800 mg/kg of the poly-saccharide compared with those in MPTP-treated mice. The activities of superoxide dismutase and glutathione peroxidase in the serum and midbrain were also increased signiifcantly in mice injected with MPTP after pretreatment with the polysaccharide fromSpirulina platensis. By con-trast, the activity of monoamine oxidase B in serum and midbrain maintained unchanged. These experimental ifndings indicate that the polysaccharide obtained fromSpirulina platensis plays a protective role against the MPTP-induced loss of dopaminergic neurons in C57BL/6J mice, and that the antioxidative properties of this polysaccharide likely underlie its neuroprotective effect.
文摘Alternative protein sources, such as insects or algae meals are in special focus of animal nutrition in order to replace soybean meal (SBM). As part of the multidisciplinary project “sustainability transitions” this study evaluated effects of replacing SBM by partly defatted larvae meal from the black soldier fly, Hermetia illucens or meal from the micro algae Spirulina platensis in broiler diets. The aim of the current study was to investigate the chickens’ growth performance and the intestinal morphology as well as the health status. 288 one-day-old male growing chickens (Ross 308) from a commercial hatchery were randomly allotted to 48 pens (6 birds per pen) for the growth study with five diets and feed supply on free choice level. The control diet was based on wheat, corn and SBM. The experimental diets replaced 50% of SBM by the alternative proteins under study, both on a basic level of amino acid (AA) supplementation (Lys and Met added equal to the control diet) (diet HM and SM) and an extended level of AA fortification (Lys, Met, Thr, Arg, Val added) (diet HM+ and SM+). Response of chickens was evaluated by zoo-technical parameters, which were under weekly control (e.g. growth, feed intake, feed conversion ratio, mortality). After finishing the growth study birds from control and the experimental diets at the basic level of AA supplementation were slaughtered after 12 hour fastening and utilized for gut morphometric analysis and histological evaluation of the health status. Diets at a basic level of AA fortification led to significant depression of growth, feed intake, feed conversion ratio, and protein conversion ratio, respectively. In addition, the acceptance of the Spirulina diet was lower (p ≤ 0.001) as compared to the Hermetia based diet. However, the extended level of AA supplementation improved all parameters significantly. Diets without extended AA supply altered some morphological parameters of the intestinal wall, but the nutritional significance of this observation needs to be verified in AA balanced diets. The health state of chicken was not impaired by the diets under study.
基金This research was supported in part by The President of The Chinese Academy of Sciences Foundation
文摘CCC plasmid was isolated from an economically important blue-green alga- Spirulina platensis (1.7×106 dalton from the S6 strain and 1.2×106 dalton from the F, strain) using a rapid method based on ultrasonic disruption of algal cells and alkaline removal of chromosomal DNA. The difference in the molecular weight of the OOC DNAs from the two strains differing in form suggests that plasmid may be related with the differentiation of algal form. This modified method, which does not use any lysozyme, is a quick and effective method of plasmid isolation, especially for filamentous blue-green algae.
基金Project (No. 10376032) supported by the National Nature Science Associate Fundation (NSAF) of China
文摘Attempts were made to culture Spirulina platensis in human urine directly to achieve biomass production and O2 evolution, for potential application to nutrient regeneration and air revitalization in life support system. The culture results showed that Spirulinaplatensis grows successfully in diluted human urine, and yields maximal biomass at urine dilution ratios of 140-240. Accumulation of lipid and decreasing of protein occurred due to N deficiency. O2 release rate of Spirulina platensis in diluted human urine was higher than that in Zarrouk medium.
文摘The growth of Arthrospira platensis and physiological changes in biomass under the effects of six rare earth elements Dy,Sm,Tb,La,Nd and Yb were evaluated.Elements were tested by three concentrations of 10,20 and 30 mg/L.According to neutron activation analysis data A.platensis’s accumulation capacity toward studied elements changes in the following order of La>Dy>Nd>Sm>Yb>Tb.The results show that Dy and La ions stimulate biomass growth and Yb ions inhibit it,while Sm,Tb and Nd ions do not affect biomass accumulation.The contents of proteins and chlorophyll a are not affected by the presence of rare earth elements in the cultivation medium.Studied elements affect to different extents carbohydrates,phycobilins,β-carotene,lipids and MDA contents in spirulina biomass.Changes in the antioxidant activity under applied metal loads reveal a moderate stress in exposed A.platensis.Cyanobacterium A.platensis can be successfully used for bioremediation of natural water contaminated with REEs as well as REEs recovery from low polluted industrial effluents.
基金Project (No. 10376032) supported by the Natural Science Association Foundation of China (NSAF)
文摘Culture ofArthrospiraplatensis （Spirulinaplatens） in human urine was investigated to get valuable biomass. NO3-N was the proper N source, in comparison with other N source, including urea, NH4-N and NO2-N. As a result, aerobic nitrification of human urine was performed, with above 93.6% nitrification percentage finally achieved with total-N （TN） load of 46.52 mg/（L.d）, in which Arthrospira platensis was successfully grown. The main compositions of the obtained biomass are close to those in Zarrouk medium. Thus, it is possible to culture Arthrospiraplatensis in nitrified human urine for food production within bioregenerative life support systems （BLSSs）.
基金supported by the Natural Science Foundation of Fujian Province (No. 2014J01141)the National Natural Science Foundation of China (No. 31270161)the Fujian-Taiwan Joint Innovative Center for Germplasm Resources and Cultivation of Crop (No. Fujian 2011 Program, [2015]75)
文摘Arsenic-contaminated water is a serious hazard for human health. Plankton plays a critical role in the fate and toxicity of arsenic in water by accumulation and biotransformation.Spirulina platensis（S. platensis）, a typical plankton, is often used as a supplement or feed for pharmacy and aquiculture, and may introduce arsenic into the food chain, resulting in a risk to human health. However, there are few studies about how S. platensis biotransforms arsenic. In this study, we investigated arsenic biotransformation by S. platensis. When exposed to arsenite（As（Ⅲ））, S. platensis accumulated arsenic up to 4.1 mg/kg dry weight.After exposure to As（Ⅲ）, arsenate（As（Ⅴ）） was the predominant species making up 64% to86% of the total arsenic. Monomethylarsenate（MMA（Ⅴ）） and dimethylarsenate（DMA（Ⅴ））were also detected. An arsenite S-adenosylmethionine methyltransferase from S. platensis（Sp Ars M） was identified and characterized. Sp Ars M showed low identity with other reported Ars M enzymes. The Escherichia coli AW3110 bearing Spars M gene resulted in As（Ⅲ） methylation and conferring resistance to As（Ⅲ）. The in vitro assay showed that Sp Ars M exhibited As（Ⅲ） methylation activity. DMA（Ⅴ） and a small amount of MMA（Ⅴ） were detected in the reaction system within 0.5 hr. A truncated Sp Ars M derivative lacking the last 34 residues still had the ability to methylate As（Ⅲ）. The three single mutants of Sp Ars M（C59S, C186 S, and C238S） abolished the capability of As（Ⅲ） methylation, suggesting the three cysteine residues are involved in catalysis. We propose that Sp Ars M is responsible for As methylation and detoxification of As（Ⅲ） and may contribute to As biogeochemistry.
基金funded by the National Key R&D Program of China(No.2018YFC0311202)the Natural Science Foundation of China(No.21662006)+3 种基金the National Natural Science Foundation of Guangdong,China(No.2018A030313903,2018A030313088,2018A0303130144 and 2018A030313626)the Program of Department of Natural Resources of Guangdong Province(No.GDNRC[2020]038 and GDNRC[2020]036)the Key Special Project for Introduced Talents Team of Southern Marine Science and Engineering Guangdong Laboratory of Guangzhou,China(No.GML2019ZD0406)the Science and Technology Program of Guangzhou,China(No.201804010321 and 201804010364).
文摘In the present study,an oligosaccharide SPO-1 from Spirulina platensis was prepared by glycosidase from a marine bacterium.The prebiotic activity of SPO-1 on the growth of Lactobacillus paracasei and Bifidobacterium animalis,and its effect on human gut microbiota were examined in vitro.The molecular weight of the tetrasaccharide SPO-1 was 650.2 Da,and it was mainly composed of glucose with α-type glycosidic linkages.The prebiotic activity score of SPO-1 was the highest for the growth of probiotic strains L.paracasei and B.animalis.Furthermore,as fermentation proceeded,SPO-1 was gradually degraded and utilized by intestinal bacteria.The results showed that after treatment with SPO-1,carbohydrate consumption and short-chain fatty acids levels were increased,especially those of i-butyric and i-valeric acids.Moreover,SPO-1 significantly promoted the abundance,diversity and composition of gut microbiota,especially stimulating the growth of Bacteroides,Escherichia-Shigella and Megamonas.In addition,the change in intestinal microbiota function predicted by phylogenetic investigation of communities by reconstruction of unobserved states(PICRUSt)after treatment with SPO-1 is mainly related to the terms“carbohydrate metabolism”and“amino acid metabolism”.These results suggest that SPO-1 is a potential oligosaccharide in regulation of intestinal microbiota.
文摘In this paper we report that CeCl3 could accelerate the synthesis of chlorophyll a and protein in spirulina platensis. and enhance the activity of oxygen evolution. We also found that the accelerations of CeCl3 in spirulina platensis culture solution of low NaHCO3 were more than in culture solution of high NaHCO3, therefore it was related to the concentration of NaHCO3 The absorption spectrum and low temperature (77 K) fluorescence emission spectrum of spirulina platensis with CeCl3 treated were significantly different from their controls,i.e.its absorption peak of phycocyanin at 620 nm was higher than that of the control.its absorption peak at the long wave region migrated from 676 to 680 nm, and its fluorecence emission ratios (730 nm/685～695 nm) of photosystem I(PSI) to photosystem Ⅱ(PS Ⅱ) were also higher than those of the control; the pitch of the spiral algal body became shorter, and induced structural changes too.
基金the Chinese Scholarship Council is greatly acknowledged
文摘A laboratory experiment was conducted to assess the bioaccumulation of Pb^2＋ and its effects on growth, morphology and pigment contents of Spirulina （Arthrosl）ira）platensis. The specimen cultured in Zarrouk liquid medium was treated with various initial metal concentrations （0, 5, 10, 30, 50 and 10μgmL^-1）. The growth ofS. platensis was adversely affected by Pb〉 at high concentrations （30, 50 and 100μgmL^-1）. However, at low concentrations （5μgmL^-1）, Pb^2＋ could stimulate its growth slightly. The pigment contents （chlorophyllα and β carotene） were decreased in a dose-dependent manner. The highest reductions （67% and 53% respectively in chlorophyll α andβ carotene） were observed in 100 μg mL^-1 treatment group. The LC50 （96 h） of Pb^2- was measured as 75.34 μg mL^-1. Apart from a few cases of filament breakages at elevated concentrations （50 and 100 μgmL^-1）, morphological abnormalities are not specific. Metal bioaccumulation increased with Pb^2- concentrations, but decreased with exposure time. The maximum accumulated amount was 188 mgg^-1 dry weight. The bioconcentration factor （BCF） reached to a peak at day 2, followed by a gradual reduction tbr all the exposure concentrations. S. platensis is able to tolerate considerably high Pb^2＋ concentrations. Consequently it can be used as a potential species to remove heavy metal from contaminated waters.
文摘An original bi-enzymatic biosensor was designed by immobilizing Arthrospira platensis cells, called Spirulina, on gold interdigitated transducers. Phosphatase and esterase activities were inhibited, respectively, by heavy metals and by pesticides. Inhibition activities were observed with different mixtures of pesticides + heavy metals. The quantification limits for Cd2+ and Hg2+ are 10-20 M in mixture and in pure solution. The quantification limits of parathion-methyl, paraoxon-methyl and triazine are respectively 10-20 M, 10-18 M and 10-20 M in mixture and pure solutions. These results show that there is no synergistic effect between the two families of pollutants. Qualitative contamination of effluent samples and their purification after passing through a municipal wastewater treatment plant were observed by our bi-enzymatic biosensor and confirmed by classical analytical techniques for heavy metal ions.
文摘The objective of this study was to measure protein quality parameters (PPV, NPU and NPUstd) of chicken diets with complete substitution of soybean meal (SBM) by Spirulina meal (SM) or partly defatted Hermetia meal (HM). N balance experiments were based on the quantitative excreta collection method, divided into starter period (10 - 20 d) and grower period (25 - 35 d). The study utilized 70 all male meat type chicken (Ross 308). Data assessment applied the exponential N utilization model of the “Goettingen approach”. The control diet was based on wheat, corn and SBM. In four experimental diets SBM was completely substituted by SM or HM, but fortified with feed amino acids (AA) both on a basic level of supplementation (Lys and Met added equal to the control diet) and on an extended level (Lys, Met, Thr, Arg, Val, Ile, His added). At a basic level of AA supplementation, complete replacement of SBM by SM or HM in chicken diets depressed dietary protein quality significantly (p 0.05). However, the extended level of AA supplementation improved protein quality parameters of the diets with both of the alternative proteins significantly (p < 0.05), but still generally not on par with the control diet. The observed responses were accentuated when the well-known effect of N intake on protein utilization was eliminated through the standardization of N intake by application of the “Goettingen approach”.
文摘Trace elements or micronutrients play a major role in the metabolism of both plants and humans. Zinc has a major specific role in metabolism when compared with other elements. The microbial biofertilizers are applied in the form of seaweed liquid extracts, microbial inoculants, biostimulators and biofortification agents. All these categories of microbial biofertilizers are involved in the enhancement of plant nutrient uptake. In the present study, Spirulina platensis is used as a biofortification agent to enhance zinc levels in cultivars of Amaranthus gangeticus, Phaseolus aureus and Tomato. Different experimental methods were followed including soaking seeds in different concentrations of Spirulina (5, 10, 15, 20, 25 and 30 g in 100 ml of water);soaking seeds in Spirulina hydrolysate at different time intervals (1, 2, 3, 4, 5 hrs and overnight);Spirulina in combination with biofertilizers, chemical fertilizer, organic fertilizer and vermicompost in various proportions (25:75;50:50;75:25) and foliar spray with different concentrations of Spirulina (25, 50, 75, and 100g in 5 litres of water) respectively. The zinc content of the yield of the cultivars was estimated and the study results indicated that there was a significant increase in zinc levels with p-value 0.015, 0.003 and 0.035 for Amaranthus gangeticus, Phaseolus aureus and Tomato respectively when compared with the control and between the set-ups, with biofortification of Spirulina platensis. The obtained results emphasize the application of Spirulina platensis to enhance the mineral nutrient in plants which are non-polluting, inexpensive, utilizable renewable resource to maintain the soil fertility.
文摘This study was conducted to evaluate the use of cyanobacteria Arthrospira platensis and cladoceran Daphnia magna biomass as complementary protein and lipid sources in diet supplementation for common carp (Cyprinus carpio L.) nursery. Three experimental diets containing A. platensis and D. magna meal at different concentrations were compared to the commercial (control) diet. Each experimental diet (ED) was set to contain D. magna and A. platensis meal at a specific combination: 2% and 5%, 2% and 7%, and 4% and 5% for ED1, ED2 and ED3, respectively. The protein and lipid content of the experimental diets ranged from 43.20% to 44.60% dry weight (DW) and 10.64% to 13.42% DW, respectively;while the protein and lipid content of the control diet were 43.00% DW and 6.72% DW, respectively. After 20 days of feeding period, ED3 group obtained the highest final body weight (BW) (58.18 ± 35.24 mg), total biomass (1936 ± 1625 mg), food conversion rate (1.34 ± 0.04), and specific growth rate (12.86 ± 0.03% BW day<sup>–1</sup>) among all treatment groups (P > 0.05);while ED1 group obtained the highest survival (75.5% ± 7.47%) among all treatment groups (P > 0.05). The total bacterial count and total pathogenic Aeromonas sp. in the culture water of the treatment groups (ranged from 2.00 to 2.65 × 10<sup>5 </sup>CFU mL<sup>–1</sup> and 3.50 to 4.12 × 10<sup>3</sup> CFU mL<sup>–1</sup>, respectively) were lower compared to the water of the control group fed (3.73 × 10<sup>5</sup> and 4.70 × 10<sup>3</sup> CFU mL<sup>–1</sup>, respectively). No significant differences in physicochemical water quality parameters were observed among treatments (P > 0.05). The current study suggests that the combination of A. platensis and D. magna biomass can be used as complementary protein and lipid sources in diet supplementation for common carp larvae and can result in a comparable fish growth, survival and feed utilization in common carp culture at the nursery phase.
文摘Objective: To investigate the ef ect of intra-peritoneal injection of purii ed exudates of axenic Spirulina platensis on the mammalian endocrine and nervous systems. Methods: The intra-peritoneal injection of the cyanobacterial exudates in mice was applied. Sex hormonal levels of testosterone and progesterone were measured using radioimmunoassay while the follicular stimulating hormone and luteinizing hormone were evaluated by direct chemiluminescence. In addition, superoxide dismutase, catalase and glutathione peroxidase were monitored in the hippocampus region using spectrophotometric method. The levels of the hippocampal monoamines, dopamine, noradrenaline and serotonin were analyzed by high performance liquid chromatography while the acetyl choline neurotransmitter was measured by colorimetric method using choline/acetylcholine assay kit. Results: A sharp disruption in the sex hormones levels of testosterone, progesterone, follicular stimulating hormone and luteinizing hormone was demonstrated in the serum of the treated mice. At the same time, a signii cant reduction in the endogenous antioxidant defense enzymes, superoxide dismutase, catalase and glutathione peroxidase was observed in the hippocampus region of the injected mice. Moreover, levels of dopamine, noradrenaline, serotonin and acetyl choline neurotransmitter in the same region were signii cantly af ected as a result of the treatment with Spirulina i ltrate. The gas chromatography-mass spectrometer and liquid chromatography mass spectrometry/mass spectrometry analysis showed the presence of some sterol-like compounds in the cyanobacterial i ltrate. Conclusions: This study demonstrated the capability of Spirulina to release detrimental bioactive metabolites into their surrounding that can disrupt the mammalian endocrine and nervous systems.
文摘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<sub>2</sub>S<sub>2</sub>O<sub>4</sub>, 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.
文摘This study on the effect of different concentrations of germanium dioxide （GeO<sub>2</sub>） on the specificgrowth rate （SGR）, pigment contents, protein content and amino acid composition of Spirulina platensisshowed that Ge was not the essential element of this alga; that GeO<sub>2</sub> could speed up growth and raiseprotein content of S. platensis, and could possibly influence the photosynthesis system. The concentrationrange of GeO<sub>2</sub> beneficial to growth of S. platensis is from 5-100 mg/l. GeO<sub>2</sub> is proposed to be util-ized to remove contamination by Chlorella spp. usually occurring in the cultivation of Spirulina.
