Spirulina Cells Research Articles

Spirulina/Arthrospira/Limnospira-Three Names of the Single Organism.

Recent advances in research techniques have enabled rapid progress in the study of spirulina, an ancient edible cyanobacteria. Nowadays, spirulina species are classified into three genera: Spirulina, Arthrospira, and Limnospira. The latter now refers to industrially manufactured spirulina strains. Whole-genome sequencing revealed gene clusters involved in metabolite production, and the physiology of spirulina. Omics technologies demonstrated the absence of hazardous compounds in spirulina cells, confirming the safety of this biomass as a food product. Spirulina is a good source of different chemicals used in food manufacturing, food supplements, and pharmaceuticals. Spirulina's enrichment with inherent biologically active substances makes it a potential supplier of natural products for dietary and pharmaceutical applications. Spirulina is also a prospective component of both terrestrial and space-based life support systems. Here, we review current breakthroughs in spirulina research and clarify fallacies that can be found in both professional literature and public media.

Identification and functional analysis of phycocyanin-derived bioactive peptides with non-small cell lung cancer cell inhibition

Non-small cell lung cancer (NSCLC) is one of the most lethal types of malignancies around the world. Phycocyanin, a type of functional food additive derived from photosynthetic pigment protein in Spirulina cells, has been verified to exhibit antineoplastic effect on NSCLC. However, the investigation on bioactive peptides of phycocyanin, especially in NSCLC, remains poorly documented. The goal of this work is to identify novel phycocyanin-derived bioactive peptides with NSCLC cell inhibition function. Phycocyanin was hydrolysed by trypsin, followed by peptides isolation, purification and identification through ultrafiltration, high performance liquid chromatography (HPLC) and mass spectrometry (MS), respectively. Three phycocyanin peptides (PCP1: AGDASVLEDR, PCP2: ADSLLSGLR and PCP3: MFDAFTK) predicted to exhibiting anticancer ability were identified. Molecular docking analysis indicated the peptides had strong interaction with epidermal growth factor receptor (EGFR), a proto-oncogene in cells. Phenotype experiments showed that peptides significantly inhibited growth and migration of A549, H1299 and LTEP-a2 cells. Moreover, they also suppressed the activity of Akt pathway of NSCLC cells. Three phycocyanin-derived peptides might be suitable for development as new anti-lung cancer agents, owing to their antineoplastic activities. The current work also provides a vital basis for further utilization of marine algae nutrient components.

Effect of hydrodynamic aeration on bioelectricity generation from photoautotrophic Spirulina platensis in biophotovoltaic devices

A biophotovoltaic (BPV) device is a type of bioelectrochemical cell that shows potential for renewable energy production using photosynthetic exoelectrogenic microorganisms. However, the technology currently has limitations due to its relatively low power output and high dependence on biofilm attachment. Thus, this paper examines the effect of hydrodynamic aeration on the bioelectricity generation of BPV devices. Aeration is widely applied in microalgae cultivation to improve the mixing effect between microalgae cells, culture medium, and air bubbles. The methodology involves the cultivation of Spirulina platensis, device fabrication, voltage measurement in both non-aeration and aeration modes, and the use of polarization curves to determine the device performance under a gradually rising external load. The BPV devices are affected by abnormal voltage drop under high external loads, which is called power overshoot. The use of aeration successfully solved the power overshoot issues over time, but it also resulted in a gradual reduction in the voltage output and power density of the BPV devices. During aeration, the BPV devices produced a peak power density of 0.121 ± 0.056 mWm−2 on Day 1, which declined to 0.048 ± 0.025 mWm−2 on Day 13. The blowing of air bubbles had some side effects on BPV devices, including causing the attachment of Spirulina cells to the container walls and accelerating the evaporation of the culture medium. This study emphasizes the role of hydrodynamic aeration in the bioelectricity generation process and opens up possibilities for wider application of BPV devices in renewable energy production.

Fabricating Strong and Stiff Bioplastics from Whole Spirulina Cells (Adv. Funct. Mater. 40/2023)

Fabricating Strong and Stiff Bioplastics from Whole Spirulina Cells (Adv. Funct. Mater. 40/2023)

Fabricating Strong and Stiff Bioplastics from Whole Spirulina Cells

AbstractSince the 1950s, 8.3 billion tonnes (Bt) of virgin plastics have been produced, of which around 5 Bt have accumulated as waste in oceans and other natural environments, posing severe threats to entire ecosystems. The need for sustainable bio‐based alternatives to traditional petroleum‐derived plastics is evident. Bioplastics produced from unprocessed biological materials have thus far suffered from heterogeneous and non‐cohesive morphologies, which lead to weak mechanical properties and lack of processability, hindering their industrial integration. Here, a fast, simple, and scalable process is presented to transform raw microalgae into a self‐bonded, recyclable, and backyard‐compostable bioplastic with attractive mechanical properties surpassing those of other biobased plastics such as thermoplastic starch. Upon hot‐pressing, the abundant and photosynthetic algae spirulina forms cohesive bioplastics with flexural modulus and strength in the range 3–5 GPa and 25.5–57 MPa, respectively, depending on pre‐processing conditions and the addition of nanofillers. The machinability of these bioplastics, along with self‐extinguishing properties, make them promising candidates for consumer plastics. Mechanical recycling and fast biodegradation in soil are demonstrated as end‐of‐life options. Finally, the environmental impacts are discussed in terms of global warming potential, highlighting the benefits of using a carbon‐negative feedstock such as spirulina to fabricate plastics.

Biosorption and bioreduction of aqueous chromium (VI) by different Spirulina strains.

Spirulina has emerged as a promising microorganism for the treatment of industrial heavy metal ions in wastewater due to their simplicity of cultivation and harvesting, rich functional binding groups and high bioreductive activity during the uptake process. While the capacities of biosorption and bioreduction for heavy metal ions differs significantly among various algal strains. Therefore, the physiological characteristics were investigated to identify the different Spirulina strains and the chromium (VI) adsorption capacities of the algal strains were also evaluated. In this study, it was found that algal strains YCX2643 and CLQ1848 performed higher removal efficiency (86.5% and 83.7%) than other four Spirulina strains (59.4%, 56.3%, 65.6% and 66.5%, respectively). Moreover, the mechanisms of chromium (VI) ions binding and biotransformation in the Spirulina cell were scrutinize by FT-IR spectroscopy and scanning electron microscopy(SEM), and it indicated that the varieties of cellular components involved in high binding affinity may cause the higher biosorption and bioreduction of aqueous chromium (VI) in algal strains YCX2643 and CLQ1848, which could be used as promising biosorbents in the removing heavy metal pollutants from wastewaters.

Use of aluminium sulphate as flocculant for spirulina (Arthrospira platensis) with notes on the use of antioxidants for preservation under refrigerated conditions

One of the bottlenecks in microalgae harvesting is the lack of an efficient method for separating the microalgae from its culture medium. Moreover, the lack of viable and simple preservation techniques for microalgae starters hinders the immediate recovery of cultures after experiencing collapse. Hence, the present study was conducted to evaluate the use of aluminium sulphate as a flocculant for harvesting spirulina (Arthrospira platensis) and compare it with other flocculation techniques (electrolytic flocculation and autoflocculation). Moreover, the use of antioxidants to lengthen the storage of viable spirulina cells in refrigerated conditions was explored. The results of the study showed that the optimum dosage of aluminium sulphate for flocculation of spirulina is 200 ppm with 94.82 ± 0.59% efficiency in 15 – 45 minutes post-administration. Moreover, the combination of ascorbic acid and alpha-tocopherol at 0.01% v/v resulted in the highest viable cells at 57.76 ± 2.48% until the 3-week refrigeration period. This may help in maintaining viable starters. However, further investigations are needed to ascertain residuals of aluminium in harvested biomass and explore low-cost options for its reduction or removal and optimize the use of antioxidants in spirulina preservation in refrigerated conditions.

Facile fabrication of 3D biochar absorbers dual-loaded with Fe3O4 nanoparticles for enhanced microwave absorption

Biochar microwave absorption (MA) materials are attracting significant attention due to their sustainability and cost-effective features. To endow them with enhanced MA performance, surface loading of magnetic nanoparticles (NPs) based on biotemplates is becoming a valid strategy. However, realizing hybrid deposition of magnetic NPs onto surfaces and internal spaces of the biotemplates still remains a big challenge for effective absorption. Herein, we proposed a novel biochar absorber based on Spirulina (SP) cells dual-loaded with Fe3O4 NPs and demonstrated their enhanced performance for MA. In this approach, the SP cells were permeabilized and deposited with Fe3O4 NPs both extracellularly and intracellularly, to obtain the precursors (Fe3O4@SPs). Then, annealing treatment was conducted at various temperatures (X °C) to fabricate the biochar absorbers (Fe3O4@SP-BCs-X). The Fe3O4@SP-BCs-700 composites exhibited the best MA performance among the samples, and the minimum reflection loss (RLmin) could attain −45.54 dB at 14.68 GHz (thickness: 1.49 mm, mass ratio in paraffin: 18.6 wt%). Moreover, the biochar absorbers with hybrid deposition could achieve enhanced absorption compared to the samples with single deposition. Due to these superior features and facile fabrication, the Fe3O4@SP-BCs demonstrated great potential for MA applications.

Screening of Spirulina strains for high copper adsorption capacity through Fourier transform infrared spectroscopy.

Microalgae have emerged as promising biosorbents for the removal of toxic metals from industrial effluents due to the presence of various free functional groups. While the constitutes are distinct among different algal strains, it needs to screen the algae with high adsorption capacities for heavy metal ions by analyzing the algal components. In this study, a rapid and nondestructive Fourier transform infrared (FTIR) method combined PCA algorithm was used to discriminate algal strains according to their cellular components. With FTIR spectroscopy, we have found that the algal strains for high copper adsorption capacity (RH44, XS58, AH53, and RZ22) can be well differentiated from other strains via assessing the components involved in the biosorption of copper ions at the spectral window range of 1,200–900 cm−1 mainly attributed to polysaccharides. Correspondingly, the copper removal efficiency by different Spirulina strains was also measured by biochemical assay and scanning electron microscopy (SEM) in order to confirm the screening result. Compared with the chemical measurement, the assessment based on spectral features appears fairly good in the evaluation and differentiation of copper adsorption capacity in various Spirulina strains. This study illustrates that FTIR spectroscopy may serve as a fast and effective tool to investigate the functional groups for copper ions binding in the Spirulina cell and it even offers a useful and accurate new approach to rapidly assess potential adsorbents for the high capacity of copper adsorption.

Anticorrosion and antibiofouling performance of in-situ prepared layered double hydroxide coating modified by sodium pyrithione on aluminum alloy 7075

The anticorrosion and antibiofouling of marine engineering equipments have strong demands, especially for antibiofouling. In this work, an in-situ growth layered double hydroxide (LDH) coating on aluminum alloys (AA) 7075 was prepared and then modified by sodium pyrithione (SPT) to increase the anticorrosion and antibiofouling performance. Results indicated that CoAl-LDHs and CoAl-LDHs-SPT coatings had been successfully prepared according to TEM, XRD, XPS, Raman spectra, and SEM analysis results. The (0 1 2) plane of LDHs with a interplanar spacing of 0.26 nm was recognized from TEM images. The content of SPT in CoAl-LDHs-SPT is 38.79 wt.%. Electrochemical impedance spectroscopy (EIS) and polarization curvies demonstrate that the corrosion resistance of AA 7075 was largely improved in the presence of CoAl-LDHs and CoAl-LDHs-SPT coatings while the anticorrosion performance of CoAl-LDHs-SPT coating was better. The corrosion resistance of Co-Al LDHs-SPT coating increased by about two orders of magnitude compared with the bare AA 7075. The surface analysis results show that only a few Pseudomonas aeruginosa and Spirulina cells attached to the CoAl-LDHs coating surface, and no biofouling cells were observed for the CoAl-LDHs-SPT coating. Co-Al LDHs-SPT coating possessed the best anticorrosion and antibiofouling properties due to the presence of SPT compared with the CoAl-LDHs coating.

CuS nanodots-loaded biohybrid magnetic helical microrobots with enhanced photothermal performance

Magnetic helical microrobots swimming at low Reynolds numbers have attracted much interest because of their great potentials for biomedical applications. However, to endow them with sophisticated function integration toward targeted disease treatment still remains a major challenge. Here, we proposed a novel strategy of using Spirulina scaffolds to fabricate biohybrid magnetic helical microrobot (BMHM) with enhanced photothermal performance to fight against cancer cells and pathogenic bacteria. For the first time, CuS nanodots were densely and uniformly loaded intracellularly inside Spirulina cells after permeabilization, and Fe3O4 nanoparticles were subsequently deposited on the cell walls for magnetization. The BMHMs could be actuated forward at a high velocity and flexibly steered under rotating magnetic fields. Rapid and great photothermal temperature raise with robust cycling stability was achieved under 808 nm near-infrared laser irradiation. The BMHMs showed good biocompatibility with minor toxicity to HeLa cancer cells and Escherichia coli bacteria. Moreover, significant photothermal performance was further verified via a series of experiments for anticancer therapy and bacteria killing. Because of the remarkable features and facile cost-effective fabrication, the BMHMs demonstrated great potentials as an integrated microrobot platform for future anticancer and antibacteria applications.

Efficient Removal of Pb(II) from Aqueous Systems Using Spirulina-Based Biohybrid Magnetic Helical Microrobots.

Wastewater remediation toward heavy metal pollutants has attracted considerable attention, and various adsorption-based materials were employed in recent years. However, it is still challenging to explore low-cost and high-efficient adsorbents with superior removal performance, nontoxicity, flexible operation, and good reusability. Herein, Fe3O4- and MnO2-loaded biohybrid magnetic helical microrobots (BMHMs) based on Spirulina cells were presented for the first time, and their performance on Pb(II) removal was studied in detail. Intracellular synthesis of Fe3O4 and MnO2 nanoparticles into Spirulina cells was successively conducted to obtain the BMHMs with superparamagnetism and high surface activity. The BMHMs could be flexibly propelled under magnetic actuation, and collective cork-screw spinning was performed to enhance fluidic diffusion with intensive adsorption. Rapid and significant removal of Pb(II) in wastewater was achieved using the swarming microrobots, and a high adsorption capacity could be reached at 245.1 mg/g. Moreover, the BMHMs could be cyclically reutilized after simple regeneration, and good specificity toward Pb(II) was verified. The adsorption mechanism was further studied, which revealed that the pseudo-second-order kinetics dominated in the adsorption process, and the Langmuir isothermal model also fitted the experimental results well. The intriguing properties of the BMHMs enable them to be versatile platforms with significant potentials in wastewater remediation.

Synergy of production of value-added bioplastic, astaxanthin and phycobilin co-products and Direct Green 6 textile dye remediation in Spirulina platensis

Phyco-remediation of dyestuffs in textile wastewaters is of economic, industrial, and environmental importance. We evaluated the remediation of the textile dye, Direct Green 6 (DG6), by Spirulina platensis, and investigated the novel possibility that DG6 treatment enhances production of the biopolymer, polyhydroxybutyrate (PHB). We showed that both live and dead cells of Spirulina were capable of DG6 remediation, but live cells could be re-used with no loss of remediation efficiency. Furthermore, DG6 remediation by live cells resulted in increased algal biomass and trichome lengths, and stimulated production of valuable metabolites, including PHB, antioxidants, carbohydrates and pigments (phycobilins and astaxanthin). We determined the optimal conditions for DG6 remediation and an artificial neural network (ANN) accurately modeled the experimental data and predicted the concentration of dye as the most and algal turbidity as the least important parameters for DG6 removal efficiency. A DG6 concentration of 60 mg L−1 resulted in the highest simultaneous co-production of PHB (12.7 ± 1.7% DW) and increase of astaxanthin (194%), carotenoids (50%), phenol (51%), carbohydrates (27%) total phycobilin (43%), together with the enhancement of biomass and trichome lengths (95%). Oxidative stress indices and enzyme activities such as peroxidases and laccase (involved in dye removal/antioxidant functions) were also increased by dye dosage. On the basis of our results, we propose that S. platensis may use DG6 dye as a nitrogen/carbon source for co-accumulation of valuable bioplastic and metabolites.

Spirulina: growth in continuous and batch bioreactors and response to stress conditions

Spirulina platensis is a cyanobacterium with high biotechnological potential. Optimization of the cultivation conditions of spirulina takes place constantly, to increase the yield of this valuable crop. An important economic indicator of the process is an increase in the yield of biomass and a decrease in the cost of its production. For example, avoiding the need to cultivate spirulina at elevated temperatures with at least equal biomass yield. The purpose of this work was to develop and compare methods for cultivating Spirulina platensis in two bioreactors, continuous and batch ones, and to assess the resistance of spirulina cells to environmental stress caused by the presence of household chemicals. It was shown that, at room temperature, the wet biomass yield was higher in the bioreactor than with batch cultivation in flasks. However, a decrease in temperature leads to a decrease in the number of colony forming units. The presence of compounds such as phosphates and phosphonates from household chemicals in the cultivation environment negatively affects the survival of Spirulina cells, which reflects the general trend of a decrease in the number of microorganisms as a result of environmental pollution with surfactants.

In vitro and in vivo hypolipidemic properties of the aqueous extract of Spirulina platensis, cultivated in colored flasks under artificial illumination.

BackgroundSpirulina is blue-green algae that grows mainly in tropical and subtropical lakes and is commonly used due to its nutritional features including high concentrations of protein, vitamins, mineral salts, carotenoids and antioxidants. This study aimed to investigate the anti-hypercholesterolemic potential of aqueous extract of Spirulina platensis cultivated in different colored flasks under artificial illumination; in vitro and in the diet induced hypercholesterolemic Swiss albino mice.MethodsSpirulina platensis was cultivated in red, blue, green and colorless Erlenmeyer flasks containing Zarrouk’s medium under aerobic conditions, with incessant illumination by artificial cool white fluorescent with light intensity of 2500 lux (35 µmol photon m−2 s−1). Chlorophyll a and total carotenoid contents were estimated using colorimetric methods, fatty acids composition was determined by GC-Mass, in vitro and in vivo anti-cholesterol assays were used in assessing the anti-hypercholesterolemia potential of obtained Spirulina cells.ResultsThe results showed that the highest cell dry weight, chlorophyl a, and carotenoid of S. platensis were observed in colorless flasks and that the lowest values were recorded with the green colored flasks. Also, the hot water extract of S. platensis obtained from colorless flasks at a concentration of 15 mg/mL after 60 min of incubation exhibited the greatest reduction of cholesterol level. Gas chromatography-mass spectrometry analysis of S. platensis methanolic extract showed 15 bioactive compounds were identified and grouped according to their chemical structures. An experimental model of hypercholesterolemic mice had been examined for impact of S. platensis individually and combined with atorvastatin drug. All S. platensis groups resulted in a remarkable decrease in plasma total cholesterol, triglycerides and low density lipoprotein; and increase in high density lipoprotein.ConclusionThe present study concluded that the hot aqueous extract of S. platensis developed in colorless flasks is recommended as a natural source for bioactive compounds, with anti-cholesterol and antioxidant potentialities.

Effect of dietary inclusion of Spirulina on production performance, nutrient digestibility and meat quality traits in post-weaning piglets.

The effect of Spirulina (Arthrospira platensis), individually or in combination with two commercial carbohydrases, in piglet diets was assessed on growth performance, nutrient digestibility and meat quality traits. Forty post-weaned male piglets from Large White×Landrace sows crossed with Pietrain boars with an initial live weight of 12.0±0.89kg were used. Piglets were assigned to one of four dietary treatments (n=10): cereal and soya bean meal base diet (control), base diet with 10% Spirulina (SP), SP diet supplemented with 0.005% Rovabio® Excel AP (SP+R) and SP diet supplemented with 0.01% lysozyme (SP+L). Animals were slaughtered after a 4-week experimental period. Growth performance was negatively affected by the incorporation of Spirulina in the diets, with an average decrease of 9.1% on final weight, in comparison with control animals. Total tract apparent digestibility (TTAD) of crude protein was higher (p<.05) in the control group than in other groups. In addition, lysozyme increased TTAD of crude fat and acid detergent fibre, relative to the SP and control groups, respectively. In addition, the incorporation of Spirulina, individually and supplemented with enzymes, did not impair meat quality traits. Surprisingly, no protective effect against lipid oxidation was observed with the inclusion of Spirulina in pork after 7days of storage. This study indicates that growth performance of post-weaning piglets was impaired by the incorporation of 10% Spirulina in the diets, which is mediated by an increase in digesta viscosity and a lower protein digestibility, as a consequence of the resistance of microalga proteins to the action of endogenous peptidases. In addition, it also indicates that lysozyme, in contrast to Rovabio® Excel AP, is efficient in the degradation of Spirulina cell wall in piglet's intestine. However, the digestion of proteins liberated by Spirulina cell wall disruption is still a challenge.

Peroxiredoxin of Arthrospira platensis derived short molecule YT12 influences antioxidant and anticancer activity

This study demonstratesboth the antioxidant and anticancer potential of the novel short molecule YT12 derived from peroxiredoxin (Prx) of spirulina, Arthrospira platensis (Ap). ApPrx showed significant reduction in reactive oxygen species (ROS) against hydrogen peroxide (H2 O2 ) stress. The complementary DNA sequence of ApPrx contained 706 nucleotides and its coding region possessed 546 nucleotides between position 115 and 660. Real-time quantitative reverse transcription polymerase chain reaction analysis confirmed the messenger RNA expression of ApPrx due to H2 O2 exposure in spirulina cells at regular intervals, in which the highest expression was noticed on Day 20. Cytotoxicity assay was performed using human peripheral blood mononuclear cells, andrevealed that at 10 μM, the YT12 did not exhibit any notable toxicity. Furthermore, ROS scavenging activity of YT12 was performed using DCF-DA assay, in which YT12 scavenged asignificant amount of ROS at 25 μM in H2 O2 -treated blood leukocytes. The intracellular ROS in human colon adenocarcinoma cells (HT-29) was regulated by oxidative stress, where the YT12 scavenges ROS in HT-29 cells at 12.5 μM. Findings show that YT12 peptide has anticancer activity, when treated against HT-29 cells. Through the MTT assay, YT12 showed vital cytotoxicity against HT-29 cells. These finding suggested that YT12 is a potent antioxidant molecule which defends ROS against oxidative stress and playsarole in redox balance.

Changes in Morphometric Indices of Arthrospira (Spirulina) platensis Cells and Trichomes during Dehydration and the Reactivation Period

The development of methods for long-term storage of microalgae remains an important and complex problem, the solution of which is impossible without studying the processes occurring during dehydration and rehydration of vegetative cells. The study presents the results from the investigation of changes in the dimensional characteristics of cells and trichomes of spirulina Arthrospira (Spirulina) platensis (Nordstedt) Gomont after dehydration and during reactivation (in dynamics) as well as processes occurring in them during reactivation. Methods close to natural dehydration were selected. Morphometric measurements of cells and trichomes of spirulina in their native state and during dehydration and rehydration were performed. Dehydration of A. platensis was accompanied by statistically significant changes in the morphometric characteristics of cells. For all methods of dehydration (in a thermostat at 30 and 60°C and on silica gel in a desiccator at a room temperature of 20°C) a decrease in their size, as well as elongation and flattening, were noted. The thickness and volume of trichomes after dehydration were reduced by two times. All processes occurring during reactivation were traced in dynamics, from the moment of moistening to the appearance of young threads. A relatively rapid flooding of the dried cells and a gradual restoration of their morphometric characteristics was noted. Among the reactivating trichomes, those in which the separation into viable and irreversibly areas damaged was clearly visible were found. Differential staining of trichomes with methylene blue revealed cells with strong plasmolysis inside externally intact threads. Morphometric parameters of the spirulina cell were restored within 24 h. This fact indicates that, in dehydrated cultures after rehydration, a number of complex biochemical processes occur, due to which the initial physiological state of the cells is restored.

Encapsulation of ellagic acid from pomegranate peels in microalgae optimized by response surface methodology and an investigation of its controlled released under simulated gastrointestinal studies.

Ellagic acid (EA), a naturally occurring bioactive phenolic compound largely found in pomegranate, exhibits significant health benefits due to its antioxidant, antimutagenic, and even anticancerogenic properties. The present work aimed to microencapsulate EA extracted from pomegranate peels. To improve the stability of EA, microencapsulation was applied with Spirulina as a coating material. For this purpose, ethanolic extracts obtained from pomegranate peels were used for microencapsulation. Response surface methodology combined with a three-level, three-variable Box-Behnken design (BBD) was applied to obtain optimum microencapsulation. The microparticles obtained under the optimized encapsulation conditions were further characterized by FT-IR and SEM. The results confirmed the encapsulation of EA in Spirulina cells. Then, the optimum microparticles were used in an in vitro release study. The results of the in vitro digestion with simulated gastrointestinal fluids could help to determine the content and biological activity of EA. In this study, the effect of encapsulation on the release properties of EA during simulated gastrointestinal digestion was also evaluated. HPLC-DAD analysis and the Folin-Ciocalteu and ABTS methods were helpful for characterization of EA in the simulated fluids. The release profile of EA indicated that in simulated intestinal fluid, the release was faster than that in gastric fluid. PRACTICAL APPLICATION: This study describes the microencapsulation of ethanolic extracts of pomegranate peel (PP) in Spirulina. This application has been performed to improve the stability and bioavailability of EA in the extracts. Optimum microencapsulation was obtained by response surface methodology with BBD. After the characterization of the obtained optimum Spirulina/EA mixture by FT-IR and SEM, an in vitro release study was conducted for stability research. The results will guide other researchers working on the determination of the content and biological activity of EA and on optimizing the microencapsulation process.

Comparative Study of Antioxidant Phycocyanin Extracts Activity between S. platensis with S. fusiformis Using DPPH Method

Phycocyanin is Spirulina’s content which has antioxidant activity to inhibit oxidation process or formation of free radicals that play a role in the initiation high-degenerative diseases. This research is aim to determine the best antioxidant activity of S. platensis with S. fusiformis through the best extraction methods of Spirulina cell between distilled water and PBS (Phosphate Buffer Solution). This research method existed Spirulina cell extraction used distilled water and PBS, and then followed by fractionation and dialysis phycocyanin extract, afterward tested the antioxidant activity used DPPH method. The result of extraction used PBS with a salt concentration of ammonium sulfate 30% produced the best purity value of phycocyanin extract of both types of Spirulina. Results of tested the antioxidant activity, S. fusiformis has the best antioxidant activity compared with S .platensis with a value of 311.43 ppm and 387.36 ppm, respectively.Keywords: Antioxidant, DPPH, Phycocyanin extracts, S. fusiformis, S. Platensis