Pigments In Cyanobacteria Research Articles

Improvement of phycocyanin stability at different temperatures using microencapsulation by whey protein isolate

Phycocyanin is a blue pigment in cyanobacteria known for its antioxidant activity and can be applied as a natural food colorant. However, one drawback to applying phycocyanin in food products is their high-temperature instability. In this research, we investigated the effect of encapsulation of phycocyanin using whey protein isolate (WPI) as the wall material to improve high-temperature stability. The study also assessed the physiochemical properties of microencapsulated phycocyanin. Phycocyanin was extracted from dry biomass Spirulina using a cold maceration method. Then, phycocyanin extract was encapsulated with prepared emulsions containing 0.25%, 0.50%, 0.75%, and 1.00% WPI as wall materials. The result showed all microencapsulated phycocyanin, regarding various concentrations of WPI, showed lower phycocyanin degradation at 60°C and 70°C at various heating times compared to control, suggesting higher stability. The control sample had 35.55±0.33% and 62.61±0.55% concentration degradation at 60°C and 70°C after 10 min heating. The microencapsulated phycocyanin with 0.50% WPI had 12.67±2.08% and 19.95±2.02% at 60°C and 70°C after 10 min heating. The encapsulation efficiency achieved 98-99% regarding various concentrations of WPI. There was no significant difference in solubility between the control and microencapsulated phycocyanin. Our result concluded that microencapsulation, using WPI as wall material, improved the high-temperature stability of phycocyanin.

Long-range dependence and extreme values of precipitation, phosphorus load, and Cyanobacteria

Extreme daily values of precipitation (1939-2021), discharge (1991-2021), phosphorus (P) load (1994-2021), and phycocyanin, a pigment of Cyanobacteria (June 1-September 15 of 2008-2021) are clustered as multi-day events for Lake Mendota, Wisconsin. Long-range dependence, or memory, is the shortest for precipitation and the longest for phycocyanin. Extremes are clustered for all variates and those of P load and phycocyanin are most strongly clustered. Extremes of P load are predictable from extremes of precipitation, and precipitation and P load are correlated with later concentrations of phycocyanin. However, time delays from 1 to 60 d were found between P load extremes and the next extreme phycocyanin event within the same year of observation. Although most of the lake's P enters in extreme events, blooms of Cyanobacteria may be sustained by recycling and food web processes.

How Might Changing Climate Limit Cyanobacteria Growth in Shallow Prairie Lakes? An Empirical Space-For-Time Evaluation of the Potential Role of Increasing Sulfate

Cyanobacteria blooms alter aquatic ecosystems and occur frequently in shallow prairie lakes, which are predicted to increase in salinity as the regional climate becomes hotter and drier. However, flat landscapes that experience depression bottom salinity with high concentrations of sulfate in addition to sodium and chloride, may mitigate nutrient increases or even inhibit cyanobacteria growth. Cyanobacteria can dominate shallow lakes with low N:P ratios because many cyanobacteria species fix dissolved N2, whether due to in-lake denitrification or exchange with the atmosphere, a process that requires molybdenum as an enzyme cofactor. Sulfate can compete with molybdate at cellular uptake sites, potentially limiting the competitive advantage of cyanobacteria. We studied 25 lakes located in a relatively limited geographic region of southern Alberta (Canada) and used a space-for-time analysis to model scenarios of increased sulfate concentrations under changing climate. Monthly, we measured nitrogen, phosphorus, sulfate, molybdenum, and cyanobacterial pigments and used mixed effects models to identify empirical relationships. Sulfate drives conductivity in the region and we found that most saline lakes we sampled are turbid lakes with high nutrients and high cyanobacteria biomass. In addition to phosphorus, molybdenum predicted cyanobacterial pigments in the top two models, showing a positive relationship with cyanobacterial biomass. We also found a negative relationship between sulfate concentration and cyanobacteria pigments, which suggests that as lakes get saltier, even with increased nutrients, there may not be an incremental increase in cyanobacteria biomass. Our results therefore suggest that competition between sulfate and molybdate may limit future cyanobacteria growth in shallow lakes and that with a warmer and drier climate it may not be inevitable that shallow lakes will continue to be dominated by cyanobacterial blooms, a hypothesis that could be tested directly via experimentation.

Cyanobacteria as biochemical energy source for the synthesis of inorganic nanoparticles, mechanism and potential applications: a review.

Green synthesis of nanoparticles (NPs) has gained great concern among researchers due to their unique properties, excellent applications and efficient route of synthesis. From the last decades, the number biologicals such as plants, fungus, bacteria, yeast, algae, and cyanobacteria and their products are using by various researchers for the synthesis of different NPs. However, the pillar of green chemistry keeps touching new heights to improve the performance. This review paper unveils almost recent cyanobacteria-assisted greener NP synthesis technique, characterization and application. The enormous potency of cyanobacteria in NP synthesis (silver, gold, copper, zinc, palladium, titanium, cadmium sulfide, and selenium) and significance of reducing enzymes were summarized. The extracellular and intracellular entity such as metabolites, enzyme, protein, pigments in cyanobacteria play a significant role in the conversion of metal ions to metal NPs with unique properties discussed briefly. The green synthesis of nanomaterials is valuable because of their cost-effective, nontoxic and eco-friendly prospects as well as the potential application metal NPs such as antibacterial, antifungal, anticancerous, catalytic, drug delivery, bioimaging, nanopesticide, nanofertilizer, sensing properties, etc. Therefore, in the present review, we have systematically discussed the mechanisms of synthesis and applications of cyanobacteria-assisted green synthesis of NPs.

English

The pigment content in Blue-green algae is a specific feature of each species. The pigment variation is specific features among microalgae. The paper aim to analyze cyanobacterial extracts of different Usar soil of Azamgarh and Varanasi, Uttar Pradesh. The main object here is the importance of the blue green algae especially because of the pigments present in this class of algae. Pigments from natural sources are gaining more importance mainly due to health and environmental issues. Algae contain a wide range of pigments. Three major classes of pigments are chlorophylls, carotenoids (carotenes and xanthophylls) and phycobilins (Phycocyanin and phycoerythrin). Our present study investigates the efficiency for phycobiliprotein pigment production from four different cyanobacteria Hapalosiphon sp., Phormidium sp., Anabaena sp. and Nostoc sp. The harvested and dried biomass was subjected to extract pigments using different solvents. Thin Layer Chromatography was performed from extracted pigments using Acetone as extraction solvents. And running solvent especially for phycocyanin pigment was optimized and concluded that Petroleum ether and Acetone in the ratio of 7:3. This paper presents the information about the natural pigments of cyanobacteria and how they can be extracted and identified using different procedures and spectrophotometry. It emphasizes that the principal algal pigments are Phycobilins, Chlorophylls and Carotenoids.

Continuous pressurized extraction versus electric fields-assisted extraction of cyanobacterial pigments

Cyanobacteria pigments, in special carotenoids and phycobiliproteins, are usually used in industry as raw extracts, although there is still no standard methodology for their extraction. For the co-extraction of carotenoids and phycobiliproteins from the marine cyanobacterium Cyanobium sp., a continuous pressurized solvent extraction (CPSE) system and an electric fields-assisted extraction system based in ohmic heating were optimized using Central Composite Designs, with three factors each: time (t), temperature (T) and, flow (f) for CPSE; and time, temperature and frequency (F) for ohmic heating. The content of pigments and the antioxidant capacity of extracts were evaluated. All tested factors seem to influence the extraction of pigments in different ways: a high temperature (70 °C) had a positive impact on the extraction rate in both methods, while the influence of time depended on the extraction principle. Flow and frequency affected directly the extraction efficiency and these methods are indeed suitable for cyanobacterial pigments extraction, achieving good extraction results. Optimal conditions for co-extraction of carotenoids and phycobiliproteins in CPSE were T = 70 °C, t = 20 min and f = 1.5 mL min−1, and for ohmic heating they were T = 70 °C, t = 5 min and F = 20 kHz. Both, CPSE and ohmic heating systems allowed obtaining better extraction yields when compared with a previously optimized extraction method (homogenization), used here as a reference. However, ohmic heating was the best methodology for pigments co-extraction from Cyanobium sp.

Bioindication of heavy metals in aquatic environment using photosynthetic pigments in cyanobacteria

Freshwater resources is seriously threatened by heavy metals pollution. Thus developing an effective screening method for the presence of heavy metals is required. In this paper, the potential of using cyanobacteria for heavy metals detection in water bodies is determined. The cyanobacteria Anabaena cylindrica had been cultured, immobilized, and exposed to Cu, Pb, and Cd with the concentrations of 0.01 – 10.00 mg/L. The responses of the cells to the heavy metals were measured for 60 min. The effect of the cell culture age and cell density were determined as well. The cells with 7 days of culture age, and the amount of cell with density of OD= 0.5 A (measured at 700 nm wavelength) were found to produce highest photosynthetic fluorescence for the detection for heavy metals. The cells were capable to provide detectable fluorescence emission within 10 min of exposure. Thus the cyanobacteria was identified as a good candidate to serve as bioindicator for the heavy metals in water.

Stochastic dynamics of Cyanobacteria in long‐term high‐frequency observations of a eutrophic lake

AbstractConcentrations of phycocyanin, a pigment of Cyanobacteria, were measured at 1‐min intervals during the ice‐free seasons of 2008–2018 by automated sensors suspended from a buoy at a central station in Lake Mendota, Wisconsin, U.S.A. In each year, stochastic‐dynamic models fitted to time series of log‐transformed phycocyanin concentration revealed two alternative stable states and random factors that were much larger than the difference between the alternate stable states. Transitions between low and high states were abrupt and apparently driven by stochasticity. Variation in annual magnitudes of the alternate states and the stochastic factors were not correlated with annual phosphorus input to the lake. At daily time scales, however, phycocyanin concentration was correlated with phosphorus input, precipitation, and wind velocity for time lags of 1–15 d. Multiple years of high‐frequency data were needed to discern these patterns in the noise‐dominated dynamics of Cyanobacteria.

Variation in phytoplankton pigment composition in relation to mixing conditions in temperate South-Central Chilean lakes

Thermal lake properties are sensitive to changes in windiness and precipitation, and affect the physical and chemical properties of the water column, which in turn control phytoplankton dynamics and primary production. We assessed the use of phytoplankton pigment profiling as a potential indicator of stratification conditions in temperate lakes in South-Central Chile. Spring and early summer phytoplankton pigment profiles and the physical and chemical limnology were analyzed in 43 lakes ranging in size, depth, altitude and catchment characteristics. Eleven lakes were sampled during both seasons. Variation in pigment composition between lakes was primarily related to stratification conditions and mixed layer light availability at the time of sampling. The dinoflagellate marker pigment peridinin was more abundant in more deeply mixed lakes with a lower mean irradiance, while chlorophyte pigments (chlorophyll b, lutein) tended to be higher in shallow (high-light) epilimnia. Diatom and chrysophyte pigments (fucoxanthin) dominated under less thermally stable and more variable light conditions. Cyanobacteria pigments (zeaxanthin), probably derived from picocyanobacteria, were relatively more abundant in very transparent, low productive lakes. Lakes in close vicinity of active volcanoes were enriched in silica and PO4-P and characterised by elevated chlorophyte marker pigments. Within strongly stratified lakes, in which the euphotic zone extended into the hypolimnion, cryptophyte pigments (alloxanthin) characterized the deep chlorophyll maxima while the epilimnion was consistently enriched with the photoprotective xanthophyll-cycle pigment violaxanthin. We conclude that major algal groups, represented by pigment biomarkers, are largely driven by changes in lake water column stratification and related mixed layer light availability as well as nutrient concentrations in temperate Chilean freshwater lakes.

Spectral discrimination of planktonic cyanobacteria and microalgae based on deep UV fluorescence

The deep ultraviolet fluorescence characteristics of several cyanobacteria and microalgae are analyzed and exploited for their discrimination in liquid samples. The proposed approach is based on relative fluorescence peak amplitude of natural pigments in cyanobacteria or other planktonic species commonly present in water bodies. The experimental results demonstrate a clear discrimination between the various species of cyanobacteria and other planktonic species. This approach can be simply implemented in fluorescence measurement systems for real-time detection of cyanobacteria, provided that they are able to operate in deep ultraviolet.

Marine Organisms as Biomedical Resources Enrich Quality of Life

The Ocean, called the ‘mother of origin of life’, is a rich source of biological and chemical diversity. Marine floras include microflora (bacteria, actinobacteria, cyanobacteria and fungi), microalgae, macroalgae (seaweeds), and flowering plants (mangroves and other halophytes). Marine organisms have unique properties as they are exposed to extreme marine environmental conditions. This vast marine floral resource offer a great way for discovery of new drugs which can fight deadly diseases like cancer, acquired immune deficiency syndrome (AIDS), arthritis, etc. Sea has got plenty of metabolites and other resources in living or dead form. Thermo-stable proteases, lipases, esterases, and starch and xylan degrading enzymes have been actively sought from bacterial and archaeal hyperthermophilic marine microorganisms. Marine cyanobacteria appear to be potential sources for production of vitamins such as B complex group and vitamin-E. The carotenoids and phycobiliprotein pigments of cyanobacteria have commercial value as natural food colouring agents, as feed additives, as enhancers of the color of egg yolks, to improve the health and fertility of cattle, as drugs and in the cosmetic industries. Some anti-HIV activity has been observed with the compounds extracted from Lyngbya lagerhaimanii and Phormidium tenue. Thus an attempt to review few marine derived biomedical resources was done emphasizing that with the advent of modern technologies it is anticipated that the marine environment will become an invaluable source of novel compounds in the future.

An LED-Based Fluorescent Sensing System for on-Site Microalgal Detection

In this work, we present a fluorescent sensing system capable of simultaneously detecting two species during microalgal co-culture, in which microalgae (C. vulgaris) and cyanobacteria (Leptolyngbya sp.) are the target species for detection. The sensing system has two different excitation light sources for stimulating chlorophyll ain microalgae and phycocyanin pigment in cyanobacteria, respectively, and a photodetector to measure corresponding fluorescent signals. This work is a significant improvement over our previous report on a fluorescent sensing system for single species [1]. Microalgae are one of the promising alternative energy sources [2]. Recent reports show that a co-culture system enhances biofuel production [3] and it is desired to monitor the population of each species. The co-inoculation of microalgae and cyanobacteria promotes the growth rate and lifespan of microalgae [4,5]. It is highly desired to simultaneously monitor the populations of microalgae and cyanobacteria in order to obtain highly efficient biofuel production. A common method is bench-top flow cytometry, which is time consuming, expensive, and difficult to deploy for on-site detection. The proposed portable fluorescent sensing system can be a viable option for on-site monitoring of co-culture solution containing microalgae and cyanobacteria. For the fluorescent sensing system, blue LEDs (448 nm peak wavelength) were selected for stimulating microalgae and amber LEDs (590 nm) for cyanobacteria. A highly sensitive silicon photomuliplier, MicroFC (SensL Inc., Cork, Ireland), was implemented to detect a low fluorescent signal from phycocyanin in cyanobacteria. Chlorophyll aand phycocyanin emit fluorescent light with the peak wavelength around 680 nm and 645 nm, respectively. Two long-pass filters, a dichroic filter with 647 nm cut-off (PIXELTEQ, Largo, FL, USA) and a color filter with 645 nm cut-off (Edmund Optics, Barrington, NJ, USA), are placed in front of the silicon photomultiplier to block the excitation light as illustrated in Figure 1. Measured results show that the photocurrent increases with the population of microalgae under the blue excitation light while its change is not significant to the amber light. Likewise, the photocurrent increases with the concentration of phycocyanin pigments under the amber excitation light while its response to the blue light is minimal. In summary, we have developed and demonstrated a portable fluorescent sensing system that is capable of differentiating microalgae and cyanobacteria. With further optimization, the developed system can be deployed in a biofuel production system for continuous monitoring of co-culture solution. Future work will also include integrated electronic circuitry for a fully standalone fluorescent detection system.

Gene expression of a two-component regulatory system associated with sunscreen biosynthesis in the cyanobacterium Nostoc punctiforme ATCC 29133.

Long-wavelength ultraviolet radiation (UVA) can damage cells through photooxidative stress, leading to harmful photosensitized proteins and pigments in cyanobacteria. To mitigate damage, some cyanobacteria secrete the UVA-absorbing pigment scytonemin into their extracellular sheath. Comparative genomic analyses suggest that scytonemin biosynthesis is regulated by the two-component regulatory system (TCRS) proteins encoded by Npun_F1277 and Npun_F1278 in the cyanobacterium Nostoc punctiforme ATCC 29133. To understand the dynamics of these genes, their expression was measured following exposure to UVA, UVB, high visible (VIS) irradiance and oxidative stress for 20, 40 and 60 min. Overall, both genes had statistically similar patterns of expression for all four conditions and were generally upregulated, except for those exposed to UVB by 60 min and for the cells under oxidative stress. The greatest UVA response was an upregulation by 20 min, while the response to UVB was the most dramatic and persisted through 40 min. High VIS irradiance resulted in a modest upregulation, while oxidative stress caused a slight downregulation. Both genes were also found to occur on the same transcript. These results demonstrate that these genes are positively responding to several light-associated conditions, which suggests that this TCRS may regulate more than just scytonemin biosynthesis under UVA stress.

Biliproteins and their Applications in Bioimaging

The brightly fluorescent phycobiliproteins are light-harvesting pigments in cyanobacteria and certain algae, covering almost the entire visible spectrum. Another type of biliproteins, the phytochrome family, comprises regulatory photoswitches in plants, fungi and many bacteria; their spectra cover an even wider range extending into the near-infrared and near-ultraviolet. In both types, the chromophores can be tuned by modulating chromophore-protein interactions, including the transition between fluorescence and photoswitching. These properties render biliproteins useful for bioimaging. Applications require not only the introduction of genes coding for apoproteins, but also genes coding for biosynthesis of the chromophores. Strategies for tuning and heterologous biosynthesis will be discussed.

Cyanobacteria detection in Guarapiranga Reservoir (São Paulo State, Brazil) using Landsat TM and ETM+ images

Algae bloom is one of the major consequences of the eutrophication of aquatic systems, including algae capable of producing toxic substances. Among these are several species of cyanobacteria, also known as blue-green algae, that have the capacity to adapt themselves to changes in the water column. Thus, the horizontal distribution of cyanobacteria harmful algae blooms (CHABs) is essential, not only to the environment, but also for public health. The use of remote sensing techniques for mapping CHABs has been explored by means of bio-optical modeling of phycocyanin (PC), a unique inland waters cyanobacteria pigment. However, due to the small number of sensors with a spectral band of the PC absorption feature, it is difficult to develop semi-analytical models. This study evaluated the use of an empirical model to identify CHABs using TM and ETM+ sensors aboard Landsat 5 and 7 satellites. Five images were acquired for applying the model. Besides the images, data was also collected in the Guarapiranga Reservoir, in Sao Paulo Metropolitan Region, regarding the cyanobacteria cell count (cells/mL), which was used as an indicator of CHABs biomass. When model values were analyzed excluding calibration factors for temperate lakes, they showed a medium correlation (R2=0.81, p=0.036), while when the factors were included the model showed a high correlation (R2=0.96, p=0.003) to the cyanobacteria cell count. The empirical model analyzed proved useful as an important tool for policy makers, since it provided information regarding the horizontal distribution of CHABs which could not be acquired from traditional monitoring techniques.

Profiles of photosynthetic pigment accumulation and expression of photosynthesis-related genes in the marine cyanobacteria Synechococcus sp.: Effects of LED wavelengths

Light quality is a significant environmental factor that influences photosynthetic pigments in cyanobacteria. In the present study, we illuminated the marine cyanobacteria Synechococcus sp. with white (350 ∼ 700 nm), red (630 nm), green (530 nm), and blue (450 nm) light emitting diodes (LEDs) and measured pigment levels (chlorophyll, carotenoid, and phycobiliprotein) and expression of photosynthesis-related genes (pebA, psbB, and psaE). The amount of photosynthetic pigments (total pigments, chlorophyll, and phycobiliproteins) was higher in the green and blue LED groups than in the white and red LED groups after 8 days of culture. The cells were prepared in a 1.5 mL solution for the analysis of the total pigments, chlorophyll, and carotenoid, and in a 2 mL for analysis of phycobiliproteins. The mRNA expression levels of pebA and psbB significantly increased after 8 days of cultivation under green and blue light, while the mRNA expression levels of psaE decreased. These results indicate that green and blue light increase the accumulation of photosynthetic pigments. In contrast red light induced mRNA expression of psaE and stimulated cell growth in Synechococcus sp.

Thermal stability improvement of blue colorant C-Phycocyanin from Spirulina platensis for food industry applications

C-Phycocyanin (C-PC) is a blue pigment in cyanobacteria, rhodophytes and cryptophytes with potential use as a value-added food colorant. Its stability was studied by examining the thermal degradation reactions in a range of temperature (25-80°C) before and after the addition of selected edible preservatives. The natural protein crosslinker methylglyoxal does not stabilize significantly C-PC whereas addition of honey or high concentration of sugars greatly diminish the blue color degradation occurring when C-PC is exposed to high temperature.Data show that the sugar preservative effect on the C-PC blue color is related to the final concentration of sugar added rather than the type of sugar. For this reason the best preservative was found to be fructose, which is the most soluble sugar among those tested, at saturation concentration. Exploratory sterilization studies have been carried out with six blue/green fructose syrups made by mixing C-PC with the natural yellow pigment Carthamus tinctorius. Both after a “low temperature” and a “high temperature” sterilization procedure the syrups remain clear and maintain their bright color with only partial blue color degradation. After the sterilization process, the syrups were monitored for two months, in such observation period the loss of blue color is minimal.

Using of cyanobacteria pigments

Photosynthetic apparatus of all organisms contains light absorbing pigments. Cyanobacteria pigments may be divided into three groups – chlorophylls, carotenoids and phycobiliproteins. Pigments may be used in the food and pharmaceutical industry. Cyanobacteria pigments features and usage possibilities are observed.

Reprint of: Application of micro-thin-layer chromatography as a simple fractionation tool for fast screening of raw extracts derived from complex biological, pharmaceutical and environmental samples

The main goal of present paper is to demonstrate the separation and detection capability of micro-TLC technique involving simple one step liquid extraction protocols of complex materials without multi-steps sample pre-purification. In the present studies target components (cyanobacteria pigments, lipids and fullerenes) were isolated from heavy loading complex matrices including spirulina dried cells, birds’ feathers and fatty oils as well as soot samples derived from biomass fuel and fossils-fired home heating systems. In each case isocratic separation protocol involving less that 1mL of one component or binary mixture mobile phases can be completed within time of 5–8min. Sensitive detection of components of interest was performed via fluorescence or staining techniques using iodine or phosphomolybdic acid. Described methodology can be applied for fast fractionation or screening of whole range of target substances as well as chemo-taxonomic studies and fingerprinting of complex mixtures, which are present in raw biological or environmental samples.

Application of micro-thin-layer chromatography as a simple fractionation tool for fast screening of raw extracts derived from complex biological, pharmaceutical and environmental samples

The main goal of present paper is to demonstrate the separation and detection capability of micro-TLC technique involving simple one step liquid extraction protocols of complex materials without multi-steps sample pre-purification. In the present studies target components (cyanobacteria pigments, lipids and fullerenes) were isolated from heavy loading complex matrices including spirulina dried cells, birds’ feathers and fatty oils as well as soot samples derived from biomass fuel and fossils-fired home heating systems. In each case isocratic separation protocol involving less that 1 mL of one component or binary mixture mobile phases can be completed within time of 5–8 min. Sensitive detection of components of interest was performed via fluorescence or staining techniques using iodine or phosphomolybdic acid. Described methodology can be applied for fast fractionation or screening of whole range of target substances as well as chemo-taxonomic studies and fingerprinting of complex mixtures, which are present in raw biological or environmental samples.