Different Species Of Cyanobacteria Research Articles

Biodegradability and bioavailability of dissolved substances in aquaculture effluent: Performance of indigenous bacteria, cyanobacteria, and green microalgae

Aquaculture is a controlled aquatic farming sector and one of the most important human food sources. Fish farming is one of the predominant, fast-growing sectors that supply seafood products worldwide. Along with its benefits, aquaculture practices can discharge large quantities of nutrients into the environment through non-treated or poorly treated wastewater. This study aims to understand the nutrient composition of fish wastewater and the use of indigenous bacteria, cyanobacteria, and microalgae as an alternative biological treatment method. Wastewater samples from a local fish farming facility were collected and treated using six different species of cyanobacteria and microalgae include Chroococcus minutus, Porphyridium cruentum, Chlorella vulgaris, Microcystis aeruginosa, Chlamydomonas reinhardtii, and Fischerella muscicola. All the samples were incubated for 21 days, and the following parameters were measured weekly: Chemical oxygen demand (COD), phosphate, total dissolved nitrogen, and dissolved inorganic nitrogen. In addition, dissolved organic nitrogen (DON), bioavailable DON (ABDON), and biodegradable DON (BDON) were calculated from the mass-balance equations. Colorimetric and digestive methods were used for the parameter measurements. The results showed that C. reinhardtii reduced the soluble COD concentration by 74.6 %, DON by 94.3 %, and phosphorous by more than 99 %. Moreover, M. aeruginosa, and C. minutus significantly reduced inorganic nitrogen species (>99 %). This alternative fish wastewater treatment method was explored to gain insight into fish wastewater nutrient composition and to create a sustainable alternative to conventional fish wastewater treatment methods.

Graphene-Mediated removal of Microcystin-LR in chitosan/graphene composites for treatment of harmful algal blooms

Water quality can be severely impacted by algal blooms alone, yet cyanotoxins, such as microcystin (MC), are potent underlying hazards produced by various species of cyanobacteria. Currently there is a need for environmentally compatible and economically viable media to address large scale application for HAB impacted waters. This study evaluated the interactions of chitosan/graphene (CSG) composites with three different species of cyanobacteria: Anabaena sp, Synechocystis sp, and Microcystis aeruginosa for both removal of algal optical density and toxins. Although results suggest that CSG has an algae dependent removal of density with a range of 40–90% removal, graphene/CSG is highly effective at MC toxin removal, removing >94% of MC-LR produced by Microcystis aeruginosa. Characterization by SEM and XRD revealed that 750 m2/g surface area graphene, imparts graphene morphology and functionality into the chitosan matrix surface, potentially enabling π-π interactions between graphene and the aromatic ring of microcystin. This proposed π-π removal mechanism of microcystin via the CSG chitosan biopolymer substrate offers a promising sustainable and selective media suitable for deployable treatment of HAB impacted waters.

The effect of different species of cyanobacteria on the rice yield and nitrogen use efficiency under different levels of nitrogen fertilizer on Alluvial West Java

Cyanobacteria or blue-green algae play an important role in rice cultivation. Nitrogen-fixing bacteria Cyanobacteria are found in rice fields, some of which can fix N2 up to 30%, produce some phytohormones, vitamins, amino acids, and organic acids increase soil fertility and rice productivity. The study was conducted in Alluvials wetland rice in Jatitujuh, Majalengka Regency, West Java. This research aimed to analyze the influence of cyanobacteria in increasing rice yield and the efficiency of inorganic N fertilizers. The study was arranged in a randomized block design with two factors. The first factor was the cyanobacteria formula, i.e.: (1) without cyanobacteria, (2) Pseudanabaena sp.+Chlorogloea sp., (3) Pseudanabaena sp.+Nostoc sp., (4) Chlorogloea sp.+Nostoc sp. The second factor was the dose of N fertilizer (0%, 50%, 75% and 100%). The highest rice yield obtained by Chlorogloea sp.+Nostoc sp with 100% N, increased by 14.75%. Application of Pseudanabaena sp. + Nostoc sp. was increased rice grain yield and straw biomass by 11.47% and 37.49%, reduced N fertilizer by 25 to 50%, and increased nutrient uptake of N, P, K by 43.73%, 34.80 %, 34.40%. Using cyanobacteria is a promising strategy to increase rice yield and reduce chemical fertilizers.

Morphological and ecologic diversity of thermophilic cyanobacteria in Maragheh mineral springs

Cyanobacteria or Blue-Green algae are photosynthetic prokaryotic organisms found in most ecological habitats. Different species of cyanobacteria are found in the hot springs. Hot springs are great examples of extreme habitats for organisms with ‘sub cosmopolitan’ geographical distribution, species happen throughout the world but only in ‘appropriate’ habitats. In thousand year ago, these ecological areas have been noticing tourism and therapeutic and organisms in them have attracted biologists. In this study, the identification of cyanobacteria was studied in five springs of Sarisou, Goshayesh, Ghareh Palchiq, Shour Sou and Isty Bulakh located in East Azarbaijan province, Maragheh city. The physicochemical analysis of springs water was carried out due to their effect on algal communities. In order to minimize the quantitative and qualitative changes of phytoplankton after sampling, the samples were fixed in formaldehyde % 4 solution. As a result of this study, a total of 30 species were identified. The highest diversity of cyanobacteria was observed in the Isty Bulakh spring with 15 species and seven genera due to lower turbidity and total hardness compared to other springs. In contrast, Ghare Palchigh spring show the least diversity of cyanobacteria due to high total hardness and turbidity. Among the taxa identified from all stations, the genus Phormidium showed the highest diversity.

Towards modeling growth rates of cyanobacteria in the Baltic Sea

Potential influences of various environmental factors (light conditions, mixed layer depth, water temperature) on growth rates of different cyanobacteria in the Baltic Sea (BS) are discussed. Growth rates were modeled as a function of quanta absorbed by phytoplankton. This in turn depends on phytoplankton exposition to light, which we simulated to represent realistic conditions encountered in the Baltic Sea in summer. We considered eight realistic scenarios (two cases of water clarity and four depths of the mixed layer). According to our calculations, exposition of phytoplankton to photosynthetically available radiation (PAR) in the BS can change about five times in case of the same solar surface insolation and water turbidity, solely due to changes in the mixed layer depth from 2 to 20 m. When we additionally accounted for differences in water turbidity, phytoplankton PAR exposition changed by one order of magnitude and this resulted in one order of magnitude differences in absorbed quanta for the same species of phytoplankton. Knowledge of single-species absorption characteristics allowed us to show that under the same water column conditions, the number of absorbed quanta varies significantly between different species of cyanobacteria, because of differences in their absorptive properties. The effectiveness of light absorption translated to different growth rates estimated for each phytoplankton species. Our research shows that further progress in phytoplankton modeling requires incorporating in the models improved information about optical properties, growth rates, and temperature and nutrient dependencies for different phytoplankton types.

An effective method for extraction of high purity phycocyanins (C-PC and A-PC) from dry biomass of Arthrospira maxima

Arthrospira maxima is reported to have the highest protein content among different species of Cyanobacteria. In the present work, extraction of C-phycocyanin (C-PC) and allophycocyanin (A-PC) from dry biomass of A. maxima was carried out for the first time using ultrasound-assisted extraction (UAE), enzyme-assisted extraction (EAE), and their combination. The total extractable C-PC and A-PC were estimated to be 47.89 and 39.95 mg g−1 dry biomass, respectively, from serial extraction. UAE resulted in better yield and purity compared with EAE. At standardized conditions of UAE (1:15 solid–liquid ratio, 20% amplitude and 4 min ultrasonication time), the highest yield, purity and extraction efficiency achieved were 44.5 mg g−1d.b, 2.0 and 93% for C-PC and 29.93 mg g−1d.b, 0.89 and 75% for A-PC, respectively. The purity observed is the highest reported in primary extraction to date. Combination of methods did not result in significant improvement with respect to yield and purity. Considering both yield and purity, ultrasound-assisted extraction alone was inferred to be the most suitable method for extraction of phycocyanins from the dry biomass of A. maxima.

Dynamic polyphosphate metabolism in cyanobacteria responding to phosphorus availability.

Despite the crucial role of polyphosphate (polyP) in aquatic environments, its metabolism in cyanobacteria responding to nutrients is poorly understood. We investigate polyP in three cyanobacteria species, specifically unicellular picocyanobacteria, under various nutritional conditions. Our experiments show that the accumulation of polyP in cyanobacteria is strongly dynamic, depending on phosphate levels and growth stages. 'Overplus' uptake of phosphorus (P) during the lag phase leads to the rapid accumulation of polyP, followed by lower polyP quotas during the exponential growth stage as a result of competing 'luxury' P uptake and polyP utilization to support rapid cell division. Cyanobacteria are capable of P deficiency responses that preferentially maintain polyP. However, preferential utilization of polyP occurs under severe P stress, suggesting the crucial role of polyP as P reserve to support cellular survival. Strong variability was observed among different species of cyanobacteria in their ability to accumulate polyP, and likely in the threshold P levels at which preferential polyP degradation occurs. This suggests that some cyanobacteria may be more adaptive to P-stressed or P-fluctuating conditions. Our results explain and provide important insights into the variability of polyP observed in aquatic environments where picocyanobacteria are the dominant primary producers.

Implication of blue green algae on yield attributes and economics of rice cultivation

Indian agriculture is presently at cross roads as it has to increase output at one hand and has to take care of environmental aspects on the other hand. Rice cultivation is also facing the same dilemma. Use of blue green algae as bio fertilizer is one possible way to minimize application of synthetic fertilizers which have far reaching implications on environment and health. Present research study was formulated to screen most suitable combination of different species of cyanobacteria on yield attribute of Vandana variety of rice grown in Hazaribagh district. Three species of cyanobacteria, Anabaena + Nostoc + Gloeotrichia was studied and was compared with controlled condition and condition with conventional fertilization. It was observed that combination of biofertilizer gives better result on all parameters when compared to conventional fertilizer.

Label-Free Analysis and Sorting of Microalgae and Cyanobacteria in Microdroplets by Intrinsic Chlorophyll Fluorescence for the Identification of Fast Growing Strains.

Microalgae and cyanobacteria are promising organisms for sustainable biofuel production, but several challenges remain to make this economically viable, including identification of optimized strains with high biomass productivity. Here we report on a novel methodology for the label-free screening and sorting of cyanobacteria and microalgae in a microdroplet platform. We show for the first time that chlorophyll fluorescence can be used to measure differences in biomass between populations of picoliter microdroplets containing different species of cyanobacteria, Synechocystis PCC 6803 and Synechococcus PCC 7002, which exhibit different growth dynamics in bulk culture. The potential and robustness of this label-free screening approach is further demonstrated by the screening and sorting of cells of the green alga Chlamydomonas reinhardtii encapsulated in droplets.

Modelling adsorption equilibrium of STX and dc-STX onto GAC samples with different pore size distribution

Many different species of cyanobacteria have been identified worldwide as a threat to drinking water safety since they are capable of producing saxitoxins (STX), one of the most toxic non-protein substances known in nature. Although removal of these components can be accomplished by adsorption on granular activated carbon (GAC), a method to accurately model how effectively they can be removed in GAC filters has not yet been published. This research investigated adsorption equilibrium of dc-STX and STX on four coconut shell GAC samples, with positive surface charge but different pore size distribution, and experimental data were mathematically modelled providing elements for future GAC filter simulations. Adsorption of STX and dc-STX could be fitted to either Langmuir or Freundlich isotherms and the GAC sample with greater amount of mesopores, presented the largest adsorption capacity for both dc-STX and STX, although its BET area and pore volume were similar to the other GAC tested.

Study on variation of lipids during different growth phases of living cyanobacteria using easy ambient sonic-spray ionization mass spectrometry.

Lipids are important components of cell membranes and thylakoids in cyanobacteria, and they play vital roles in various biological activities. Real-time tracing of the variation of membrane lipids can provide insights of the physiological status of cyanobacterial cells. In this work, easy ambient sonic-spray ionization mass spectrometry (EASI-MS) was utilized to investigate the changes of acidic lipids in unicellular (Synechocystis 6803, Synechococcus 7002) and filamentous (Anabaena 7120) cyanobacteria during different growth phases. A sqdX mutant with a reduced synthesis of sulfoquinovosyl diacylglycerol (SQDG) was constructed to verify the acquired data of EASI-MS. Principal component analysis (PCA) was performed to compare the acquired data, enabling the discrimination of different species of cyanobacteria in day-to-day analysis. The results showed that the three representative cyanobacteria and their growth status can be easily determined on the basis of the lipids components detected by EASI-MS. Very interestingly, significant decreases of the ratios of SQDG/PG and dramatic changes of the unsaturation level of lipids were observed in different culture times in these cyanobacteria, and these two unique characters can be used describe the aging of cyanobacteria.

The protective role of l-carnitine against cylindrospermopsin-induced oxidative stress in tilapia (Oreochromis niloticus)

Cylindrospermopsin (CYN) is one of the most important cyanotoxins in terms of both human health and environmental quality and is produced by several different species of cyanobacteria, including Aphanizomenon ovalisporum. The principal mechanisms of action of CYN involve inhibition of protein and glutathione synthesis. In addition, CYN-mediated genotoxicity results from DNA fragmentation. The results of both in vivo and in vitro studies suggest that oxidative stress also plays a significant role in CYN pathogenesis in fish. We investigated the protective effects of l-carnitine (LC) pre-treatment on A. ovalisporum-induced oxidative stress in cells containing CYN and deoxy-CYN, or pure standard CYN, in tilapia (Oreochromis niloticus) that had been acutely exposed via oral administration. Various oxidative stress markers, including lipid peroxidation (LPO), protein oxidation, DNA oxidation, and the ratio of reduced glutathione to oxidised glutathione (GSH/GSSG), and the activities of NADPH oxidase, superoxide dismutase (SOD), catalase (CAT), and gamma-glutamyl-cysteine synthetase (γ-GCS), were evaluated in the livers and kidneys of fish in the absence and presence of 400 or 880mgLC/kgfish/day during a 21 day period prior to CYN-intoxication. The results of our study demonstrated for the first time the beneficial antioxidant effects of LC dietary supplementation on oxidative stress status in fish. No pro-oxidant effects were detected at any of the LC doses assayed, suggesting that LC is a chemoprotectant that reduces hepatic and renal oxidative stress and may be effective when used for the prophylaxis and treatment of CYN-related intoxication in fish.

Reconstruction and Comparison of the Metabolic Potential of Cyanobacteria Cyanothece sp. ATCC 51142 and Synechocystis sp. PCC 6803

Cyanobacteria are an important group of photoautotrophic organisms that can synthesize valuable bio-products by harnessing solar energy. They are endowed with high photosynthetic efficiencies and diverse metabolic capabilities that confer the ability to convert solar energy into a variety of biofuels and their precursors. However, less well studied are the similarities and differences in metabolism of different species of cyanobacteria as they pertain to their suitability as microbial production chassis. Here we assemble, update and compare genome-scale models (iCyt773 and iSyn731) for two phylogenetically related cyanobacterial species, namely Cyanothece sp. ATCC 51142 and Synechocystis sp. PCC 6803. All reactions are elementally and charge balanced and localized into four different intracellular compartments (i.e., periplasm, cytosol, carboxysome and thylakoid lumen) and biomass descriptions are derived based on experimental measurements. Newly added reactions absent in earlier models (266 and 322, respectively) span most metabolic pathways with an emphasis on lipid biosynthesis. All thermodynamically infeasible loops are identified and eliminated from both models. Comparisons of model predictions against gene essentiality data reveal a specificity of 0.94 (94/100) and a sensitivity of 1 (19/19) for the Synechocystis iSyn731 model. The diurnal rhythm of Cyanothece 51142 metabolism is modeled by constructing separate (light/dark) biomass equations and introducing regulatory restrictions over light and dark phases. Specific metabolic pathway differences between the two cyanobacteria alluding to different bio-production potentials are reflected in both models.

Biochemical and genetic alterations in the freshwater neotropical fish Prochilodus lineatus after acute exposure to Microcystis aeruginosa

Microcystins are secondary metabolites produced by different species of cyanobacteria, such as Microcystis aeruginosa (MA). In this study, the biochemical and genetic effects of lyophilized MA were evaluated in the neotropical fish Prochilodus lineatus exposed to 1 or 2 mg L-1 lyophilized MA (treated group) or only water (control group) in static toxicity tests for 24 and 96 h. The gills and liver were used in the analysis of biotransformation enzymes and antioxidant defenses, blood and gill cells in genetic analysis and in brain and muscle it was determined the activity of acetylcholinesterase (AChE). The results showed the biotransformation pathway activation due to the increase in hepatic CYP1A and in branchial and hepatic glutathione S-transferase (GST). The antioxidant defense proved to be greatly affected by MA exposure leading to changes, both in gills and liver, in the activities of superoxide dismutase (SOD), catalase (CAT), glutathione peroxidase (GPx), glutathione reductase (GR) and in the content of tripeptide glutathione (GSH). Lipid peroxidation was not detected, but damage to DNA molecule was observed in blood cells. In conclusion, it can be state the lyophilized MA is able to promote changes in the biochemical and genetic parameters of P. lineatus.

Pro- and anti-inflammatory cytokine expression in carp blood and head kidney leukocytes exposed to cyanotoxin stress – An in vitro study

Cyanotoxins are toxic, secondary metabolites produced by different species of cyanobacteria that are present all over the world in aquatic environments. No data are available about the molecular mechanisms underlying the stress associated with exposure of fish immune cells to low concentrations of cyanotoxins. The purpose of this study was to determine whether the expression of cytokines that underlie immune regulation are changed after incubation of fish leukocytes with pure cyanotoxins: microcystin- LR (MC-LR), anatoxin-a (Antx-a), or an extract containing Antx-a. The study investigated the relative gene expression of four important cytokines, IL-1β, TNF-α, IL-10, and TGF-β, in carp head kidney and blood leukocytes exposed to toxins at concentrations of 0.01 or 0.1 μg/ml for 4 h. The data showed that pure toxins could induce dysregulation of pro-/anti-inflammatory cytokine expression. Expression of cytokine IL-1 β was highly upregulated following Antx-a exposure, whereas MC-LR induced merely moderate reactions. The expression of TNF-α mRNA was significantly suppressed in blood and head kidney cells incubated with toxins at the higher concentration. These results showed that pure toxins dysregulated the expression of pro-inflammatory cytokines IL-1β and TNF-α more promptly than the anti-inflammatory cytokines TGF-β and IL-10. In contrast, the studies demonstrated a clearly downward trend of pro-inflammatory cytokines and an upward trend of anti-inflammatory cytokines in leukocytes exposed to an extract containing defined concentrations of Antx-a. This study suggests that cyanotoxins present in aquatic environments may exert immunotoxic effects by altering the transcription of important mediators of the fish immune system.

In vivo mass‐specific absorption spectra of phycobilipigments through selective bleaching

We describe how bleaching with β‐cyclocitral can be used to isolate the in vivo absorption of phycobilipigments in phytoplankton, particularly cyanobacteria. Exposure to an emulsion of β‐cyclocitral bleaches chlorophylls, carotenoids, and xanthophylls within minutes while phycobilipigments bleach at a slower rate. Serial spectral absorption measurements are used to isolate the absorption spectrum of the phycobilipigments after other pigments have already bleached. Subsequently, in vivo absorption spectra are reconstructed for both pigment groups and expressed as the pigment mass‐specific absorption coefficients. These coefficients are used widely in optical modeling and remote sensing studies but have thus far not been provided for the group of phycobilipigments. In vivo mass—specific absorption spectra for phycoyanin (with allophycocyanin) and chlorophyll a (with carotenoids, xanthophylls) were highly consistent between different species of cyanobacteria that were rich in phycocyanin. Fitting these pigment‐specific absorption spectra to the in vivo absorption of cultures that also contain phycoerythrin, we were able to derive specific absorption spectra for phycoerythrin. All tested cyanobacteria and rhodophytes responded to the treatment, with varying pigment bleaching rates. A diatom also bleached rapidly whereas two chlorophytes were highly resistant. The method is therefore not yet suitable for (natural) mixed phytoplankton samples.

Microbes and Ooids

Abstract The Bahamian Archipelago is one of the few locations in the world where ooid formation is actively occurring. Ooid cortices from six locations in the region were incrementally dissolved and analyzed for 14C, δ18O, δ13C, Mg/Ca, and Sr/Ca ratios. Ooids were examined under SEM after each step in the incremental analyses to characterize the nature of dissolution. Radiocarbon dating indicates that ooids presently at the sediment–water interface began forming across the Archipelago between 1000 and 2800 yr BP and continue to form today. The ooids have the same pattern of microboring alteration across the region. The surface and outer cortex of the ooids are punctuated with unfilled microborings, whereas the inner cortex contains two morphologies of aragonite cement filling the microborings. The two morphologies of cement form in association with two different species of cyanobacteria, one is Solentia sp. the other is interpreted to be Hyella sp. The chemistry of ooids from across the region is remarkably similar. δ18O and δ13C values for all samples vary directly, having a slope of approximately 1. The outer cortex has low δ18O and δ13C values of −3.4‰ and 0.2‰ respectively, whereas the δ18O and δ13C values of the inner cortex are high with values of 1.9‰ and 6.8‰ respectively. The presence of aragonite cement in microborings in the inner cortex increases the overall isotopic composition of both oxygen and carbon in the ooid, causing it to appear close to equilibrium with seawater. The isotopic variation in δ18O and δ13C within the cortex can be characterized as a mixing line between the low values in the unaltered ooid laminae and the aragonite cement in the microborings. The most exterior portion of the ooid has very high Mg/Ca values and is interpreted as an amorphous calcium carbonate (ACC) coating. There are two other phases in the cortex, both being aragonite. The outer cortex has a higher Mg/Ca ratio and lower Sr/Ca ratio than the inner cortex. This difference in chemistry is a result of the presence of aragonite cement in the inner cortex. Stable isotopic and trace element results coupled with SEM investigations indicate that microbes do not play a role in ooid formation, but instead alter the texture and chemistry of ooids after they have formed. A new model of ooid formation is proposed whereby a veneer of ACC precipitates on an ooid while it is at the sediment–water interface (the active phase). This veneer of ACC later recrystallizes to aragonite needles and a new cortex layer is formed (the stationary phase). Observations from this study lead to a deeper understanding of the chemical processes involved in ooid genesis, which allow a better understanding of paleoenvironments hosting ooid formation.

Theoretical Analysis of the Potential of Silver Carp Hypophthalmichthys Molitrix in the Control of Water Blooming by Different Species of Cyanobacteria

Searching the way to prevent reservoirs from blooming by cyanobacteria has been one of the principal objectives of the modern hydrobiology during the last decades. A great number of different physical, chemical and biological methods to prevent blooming have been developed since, with the method of foodweb manipulation occupying a special place. This approach is the most ecologically sound management strategy (Datta, Jana, 1998). In most cases biomanipulation led to an improvement in the water quality (e.g. Annadotter et al., 1999; Gulati, van Donk, 2002). The ‘classical’ approach in biomanipulation is the increase of carnivorous fish biomass and/ or decrease of planktivorous fish biomass (e.g. Lammens, 1999; Drenner, Hambright, 2002), which leads to the increase of zooplankton biomass and reduction of cyanobacteria concentration. Journal of Siberian Federal University. Biology 4 (2009 2) 403-417 ~ ~ ~

A toxic cyanobacterial bloom in an urban coastal lake, Rio Grande do Sul state, Southern Brazil.

Reports of cyanobacterial blooms developing worldwide have considerably increased, and, in most cases, the predominant toxins are microcystins. The present study reports a cyanobacterial bloom in Lake Violão, Torres, Rio Grande do Sul State, in January 2005. Samples collected on January 13, 2005, were submitted to taxonomical, toxicological, and chemical studies. The taxonomical analysis showed many different species of cyanobacteria, and that Microcystis protocystis and Sphaerocavum cf. brasiliense were dominant. Besides these, Microcystis panniformis, Anabaena oumiana, Cylindrospermopsis raciborskii, and Anabaenopsis elenkinii f. circularis were also present. The toxicity of the bloom was confirmed through intraperitoneal tests in mice, and chemical analyses of bloom extracts showed that the major substance was anabaenopeptin F, followed by anabaenopeptin B, microcystin-LR, and microcystin-RR.

Comparison of Fluorescence Immunochromatographic Assay Strip and Gold Colloidal Immunochromatographic Assay Strip for Detection of Microcystin

Microcystins are a family of cyclic polypeptides produced by different species of cyanobacteria (blue green algae), which can form blooms in lakes and water reservoirs. However, it is difficult to detect microcystins directly in the water since the concentration of the toxins in water is usually too low. It is necessary to develop a simple and quick method to detect microcystins. In this paper, different detection characteristics of fluorescence immunochromatography and gold colloidal immunochromatography for analysis of cyanobacterial toxins were studied. These two immunochromatography assays are easy to perform, rapid, sensitive, and their quantitative range is within detectable microcystin concentrations in water samples. The fluorescence immunochromatographic system has the unique advantages of low detection limit, and satisfactory accurate results are obtained. The gold colloidal immunochromatographic system has the strong advantage of direct detection of microcystins at the test site without having to bring the samples back to the laboratory. Therefore, these two techniques supplement each other.