Development, characterization and Lactobacillus plantarum encapsulating ability of novel C-phycocyanin-pectin-polyphenol based hydrogels.

In this study, it was found that the enhancement in the viability of Lactobacillus plantarum under gastrointestinal conditions by encapsulating them within novel C-Phycocyanin-pectin based hydrogels (from 5.7 to 7.1 log/CFU). The hardness, the strength and the stability of the hydrogels increased when the protein concentration was increased. In addition, the addition of resveratrol (RES), and tannic acid (TA) could improve the hardness (from 595.4 to 608.3 and 637.0 g) and WHC (from 93.9 to 94.2 and 94.8 %) of the hydrogels. The addition of gallic acid (GA) enhanced the hardness (675.0 g) of the hydrogels, but the WHC (86.2 %) was decreased. During simulated gastrointestinal conditions and refrigerated storage, the addition of TA enhanced the viable bacteria counts (from 6.8 and 8.0 to 7.5 and 8.5 log/CFU) of Lactobacillus plantarum. Furthermore, TA and GA are completely encased by the protein-pectin gel as an amorphous state, while RA is only partially encased.

Concurrent enhancement of biomass production and phycocyanin content in salt-stressed Arthrospira platensis: A glycine betaine- supplementation approach.

In industrial-scale cultivation of microalgae, salinity stress often stimulates high-value metabolites production but decreases biomass yield. In this research, we present an extraordinary response of Arthrospira platensis to salinity stress. Specifically, we observed a significant increase in both biomass production (2.58 g L-1) and phycocyanin (PC) content (22.31%), which were enhanced by 1.26-fold and 2.62-fold, respectively, compared to the control, upon exposure to exogenous glycine betaine (GB). The biochemical analysis reveals a significant enhancement in carbonic anhydrase activity and chlorophyll a level, concurrent with reductions in carbohydrate content and reactive oxygen species (ROS) levels. Further, transcriptomic profiling indicates a downregulation of genes associated with the tricarboxylic acid (TCA) cycle and an upregulation of genes linked to nitrogen assimilation, hinting at a rebalanced carbon/nitrogen metabolism favoring PC accumulation. This work thus presents a promising strategy for simultaneous enhancement of biomass production and PC content in A. platensis and expands our understanding of PC biosynthesis and salinity stress responses in A. platensis.

Identification and molecular docking of tyrosinase inhibitory peptides from allophycocyanin in Spirulina platensis.

BACKGROUND: Tyrosinase, a copper-containing metalloenzyme with catalytic activity, is widely found in mammals. It is the key rate-limiting enzyme that catalyzes melanin synthesis. For humans, tyrosinase is beneficial to the darkening of eyes and hair. However, excessive deposition of melanin in the skin can lead to dull skin color and lead to pigmentation. Therefore, many skin-whitening compounds have been developed to decrease tyrosinase activity. This study aimed to identify a new tyrosinase inhibitory peptide through enzymatic hydrolysis, in vitro activity verification, molecular docking, and molecular dynamics (MD) simulation. RESULTS: A tripeptide Asp-Glu-Arg (DER) was identified, with a '-CDOCKER_Energy' value of 121.26 Kcal mol-1 . DER has effective tyrosinase inhibitory activity. Research shows that its half maximal inhibitory concentration value is 1.04 ± 0.01 mmol L-1 . In addition, DER binds to tyrosinase residues His85, His244, His259, and Asn260, which are key residues that drive the interaction between the peptide and tyrosinase. Finally, through MD simulation, the conformational changes and structural stability of the complexes were further explored to verify and supplement the results of molecular docking. CONCLUSION: This experiment shows that DER can effectively inhibit tyrosinase activity. His244, His259, His260, and Asn260 are the critical residues that drive the interaction between the peptide and tyrosinase, and hydrogen bonding is an important force. DER from Spirulina has the potential to develop functional products with tyrosinase inhibition. © 2024 Society of Chemical Industry.

Improving the colloidal stability of pectin-phycocyanin complexes by increasing the mixing ratio.

In the food industry, the phycobiliprotein phycocyanin acts as a color pigment or the functional part of the superfood "Spirulina." It is industrially extracted from Arthrospira platensis. Current scientific research is focusing on finding complex partners with the potential to stabilize phycocyanin against its sensitivity toward heating and pH changes. Less attention is paid to the factors that influence complexation. This study focuses on the mixing ratio of phycocyanin with pectin. Phycocyanin concentration was fixed, and the mixing ratios ranged from 0.67 to 2.50 (pectin:phycocyanin). All samples were analyzed for their color, size, microscopic structure, zeta potential, and sedimentation stability before and after heating at 85°C. It was found that increasing the pectin content fostered the initial interactions with the protein and chromophore, resulting in a color shift from blue to turquoise. The size of the complexes decreased from several micrometers to nanometers with increasing pectin concentration. Those smaller complexes that were formed at a mixing ratio of 2.5 showed a higher colloidal stability over a period of ∼2 days. It is suggested that at a low mixing ratio (0.67), phycocyanin cannot be completely entrapped within the complexes and attaches to the complex surface as well. This results in aggregation and precipitation of the complexes upon heating. With increasing aggregation and consequently size as well as density of the complexes, sedimentation was accelerated. PRACTICAL APPLICATION: Under acidic conditions, as found in many foods and beverages (e.g., soft drinks, hard candy), phycocyanin tends to agglomerate and lose its color. Specifically heating, triggers denaturation, causing phycocyanin to aggregate and lose vital protein-chromophore interactions necessary to maintain a blue color. To prevent precipitation of the phycocyanin-pectin complexes, increasing the amount of pectin to a ratio of at least 2.0 is effective. This illustrates how adjusting the mixing ratio improves stability. Conversely, lower mixing ratios  induce color precipitation, valuable in purification processes. Thus, practical use of biopolymer-complexes, requires determination of the optimal mixing ratio for the desired effect.

Optimization and Characterization of Spirulina and Chlorella Hydrolysates for Industrial Application.

Chlorella and Spirulina are the most used microalgae mainly as powder, tablets, or capsules. However, the recent change in lifestyle of modern society encouraged the emergence of liquid food supplements. The current work evaluated the efficiency of several hydrolysis methods (ultrasound-assisted hydrolysis UAH, acid hydrolysis AH, autoclave-assisted hydrolysis AAH, and enzymatic hydrolysis EH) in order to develop liquid dietary supplements from Chlorella and Spirulina biomasses. Results showed that, EH gave the highest proteins content (78% and 31% for Spirulina and Chlorella, respectively) and also increased pigments content (4.5 mg/mL of phycocyanin and 12 µg/mL of carotenoids). Hydrolysates obtained with EH showed the highest scavenging activity (95-91%), allowing us, with the other above features, to propose this method as convenient for liquid food supplements development. Nevertheless, it has been shown that the choice of hydrolysis method depended on the vocation of the product to be prepared.

Selenium enhances photodynamic therapy of C-phycocyanin against lung cancer via dual regulation of cytotoxicity and antioxidant activity.

As a natural photosensitizer, phycocyanin (PC) has high efficiency and uses low-intensity irradiation. To enhance the photodynamic therapy (PDT) of PC, we extract selenium-enriched phycocyanin (Se-PC) from Se-enriched Spirulina platensis and examine the synergistic effect of PC combined with selenium against lung tumors. In vitro experiments reveal that Se-PC PDT more efficiently reduce the survival rate of mouse lung cancer cells (LLC cell line) than PC PDT treatment by increasing the level of ROS and decreasing the level of GPx4, which is confirmed by the Chou-Talalay assay. In vivo imaging system analysis reveal that tumor volume is more markedly decreased in both the Se-PC PDT and PC PDT plus Na 2SeO 3 groups than in the PC PDT group, with inhibition rates reaching 90.4%, 68.3% and 53.1%, respectively, after irradiation with 100 J/cm 2 laser light at 630 nm. In normal tissues, Se-PC promotes the synthesis of antioxidant enzymes and the immune response by the IL-6/TNF-α pathway against tumor proliferation and metastasis. Using Se-PC as a photosensitizer in tumors, apoptosis and pyroptosis are the primary types of cell death switched by Caspases-1/3/9, which is confirmed by TEM. Based on the transcriptome analysis, Se-PC PDT treatment inhibits angiogenesis, regulates inflammation by the HIF-1, NF-κB and TGF-ß signaling pathways and dilutes tumor metabolism by reducing the synthesis of glucose transporters and transferrin. Compared to PC PDT, Se-PC increases the expression levels of some chemokines in the tumor niche, which recruits inflammatory cells to enhance the immune response. Our study may provide evidence for Se-PC as an effective photosensitizer to treat lung cancer.

Osteogenic differentiation of human amniotic mesenchymal stem cells by phycocyanin and phycoerythrin pigments isolated from Spirulina platensis and Gracilaria gracilis algae.

Bone regeneration is a multistep and regular physiological process that occurs normally in fracture repair and bone defects. However, some factors such as aging, particular diseases and some drugs prevent or slowdown bone natural healing. Cell therapy using stem cells and differentiation activating factors is an effective treatment method for bone regeneration triggering in unusual conditions. Therefore, in the present study the effect of phycocyanin and phycoerythrin pigments which isolated from Spirulina platensis and Gracilaria gracilis algae was investigate on osteogenic differentiation potency of human Amniotic Mesenchymal Stem Cells (hAMSCs). For this purpose, hAMSCs were exposed to 300, 500, and 700 µg/ml concentrations of phycocyanin and phycoerythrin pigments and then the cells viability was measured with MTT assay in 48 and 72 h after treatment. The osteo-differentiation level of cells was studied by measuring ALP activity using calorimetric method and Alizarin red staining for calcium deposition in 7 and 21 days after treatment. Also, total RNA of cells was extracted in different time periods and then cDNA synthesized with specific primers, and relative expression of Runx2, ß-catenin and Osteocalcin genes were investigated using SYBR Green RT-qPCR technique. Osteogenic differentiation of hAMSCs that treated with pigments was confirmed by mineral deposits staining and increased level of ALP activity. Furthermore, these pigments elevated significantly the expression of osteogenic marker genes compared to control samples and caused hAMSCs to differentiate into osteoblast cells. According to these results, phycocyanin and phycoerythrin may suggest as suitable osteogenic supplements with low toxicity, low cost and high efficiency, although the molecular mechanism of its efficacy is not available yet.

Phycocyanin as a nature-inspired antidiabetic agent: A systematic review.

BACKGROUND: Nutraceuticals have been important for more than two decades for their safety, efficacy, and outstanding effects. Diabetes is a major metabolic syndrome, which may be improved using nutritional pharmaceuticals. Some microalgae species, such as spirulina, stand out by providing biomass with exceptional nutritional properties. Spirulina has a wide range of pharmacological effects, mostly related to phycocyanin. Phycocyanin is a protein compound with antidiabetic properties, known as a nutraceutical. OBJECTIVE: This review delves into phycocyanin applications in diabetes and its complications and ascertains the mechanisms involved. METHODS: Scopus, PubMed, Cochrane Library, Web of Science, and ProQuest databases were systematically reviewed (up to April 30, 2023), in which only animal and cellular studies were found. RESULTS: According to animal studies, the administration of phycocyanin affected biochemical parameters (primary outcome) related to diabetes. These results showed an increase in fasting insulin serum and a decrease in fasting blood glucose, glycosylated serum protein, and glycosylated hemoglobin. In cellular studies, though, phycocyanin prevented methylglyoxal and human islet amyloid polypeptide-induced dysfunction in ß-cells and induced apoptosis through different molecular pathways (secondary outcome), including activation of Nrf2, PI3K/Akt, and suppression of JNK and p38. Also, phycocyanin exerted its antidiabetic effect by affecting the pathways regulating hepatic glucose metabolism. CONCLUSIONS: Thus, based on the available information and literature, targeting these pathways by phycocyanin may unleash an array of benefits, including positive outcomes of the antidiabetic effects of phycocyanin as a nutraceutical. OTHER: This systematic review was registered in the International Prospective Register of Systematic Reviews (PROSPERO) at the National Institute of Health. The registration number is CRD42022307522.

Caries affected disinfection using Phycocyanin activated by PDT, Holy Basil, and Ti-sapphire laser on adhesive bond strength, microleakage, and bond failure.

AIM: To investigate the effect of different cavity disinfectants, Phycocyanin (PC), Ocimum Sanctum (OS), and Ti Sapphire Laser, on the bond integrity and microleakage of resin restorations. MATERIAL AND METHOD: 60 human mandibular molars were extracted and prepared based on ICDAS scores of 4 and 5. To obtain the CAD surface, a visual examination was supported by tactile sensation and a dye for caries detection. Samples were randomly allocated into 4 groups based on cavity disinfectants applied (n = 15). Group 1: Specimens disinfected with CHX, Group 2: Specimens disinfected with Ti sapphire laser, Group 3: Specimens disinfected with Phycocyanin activated by Photodynamic therapy, and Group 4: Specimens disinfected with OS. Following the disinfection of the CAD surfaces, composite bulk-fill restorative material was bonded to each specimen and all samples were subjected to thermocycling. Ten samples from each group underwent SBS testing performed on a universal testing machine. Five samples were subjected to a microleakage analysis. RESULT: The maximum microleakage scores were displayed by Group 3: PC (0.521 nm) treated specimens. Whereas, and minimum microleakage was exhibited by Group 4: OS (0.471 nm). Group 4: OS (23.06±0.21 MPa) treated group displayed the maximum bond scores of resin adhesive to the CAD surface. However, Group 3: PC (21.67±0.24 MPa) treated specimens exhibited the lowest bond scores. Failure mode analysis revealed that among all the investigated groups the predominant type of failure was cohesive failure i.e., Group 1 (80%), Group 2 (80%), Group 3 (70%), and Group 4 (90%). CONCLUSION: Ocimum Sanctum, Phycocyanin activated by Photodynamic therapy, and Ti-sapphire laser for disinfection of caries-affected dentin have shown promise in terms of improved bond strength and reduced microleakage.

Mechanisms of action of non-enzymatic antioxidants to control oxidative stress during in vitro follicle growth, oocyte maturation, and embryo development.

In vitro follicle growth and oocyte maturation still has a series of limitations, since not all oocytes matured in vitro have the potential to develop in viable embryos. One of the factors associated with low oocyte quality is the generation of reactive oxygen species (ROS) during in vitro culture. Therefore, this review aims to discuss the role of non-enzymatic antioxidants in the control of oxidative stress during in vitro follicular growth, oocyte maturation and embryonic development. A wide variety of non-enzymatic antioxidants (melatonin, resveratrol, L-ascorbic acid, L-carnitine, N-acetyl-cysteine, cysteamine, quercetin, nobiletin, lycopene, acteoside, mogroside V, phycocyanin and laminarin) have been used to supplement culture media. Some of them, like N-acetyl-cysteine, cysteamine, nobiletin and quercetin act by increasing the levels of glutathione (GSH), while melatonin and resveratrol increase the expression of antioxidant enzymes and minimize oocyte oxidative stress. L-ascorbic acid reduces free radicals and reactive oxygen species. Lycopene positively regulates the expression of many antioxidant genes. Additionally, L-carnitine protects DNA against ROS-induced damage, while acteoside and laminarin reduces the expression of proapoptotic genes. Mogrosides increases mitochondrial function and reduces intracellular ROS levels, phycocyanin reduces lipid peroxidation, and lycopene neutralizes the adverse effects of ROS. Thus, it is very important to know their mechanisms of actions, because the combination of two or more antioxidants with different activities has great potential to improve in vitro culture systems.

The Cyanobacterial "Nutraceutical" Phycocyanobilin Inhibits Cysteine Protease Legumain.

The blue biliprotein phycocyanin, produced by photo-autotrophic cyanobacteria including spirulina (Arthrospira) and marketed as a natural food supplement or "nutraceutical," is reported to have anti-inflammatory, antioxidant, immunomodulatory, and anticancer activity. These diverse biological activities have been specifically attributed to the phycocyanin chromophore, phycocyanobilin (PCB). However, the mechanism of action of PCB and the molecular targets responsible for the beneficial properties of PCB are not well understood. We have developed a procedure to rapidly cleave the PCB pigment from phycocyanin by ethanolysis and then characterized it as an electrophilic natural product that interacts covalently with thiol nucleophiles but lacks any appreciable cytotoxicity or antibacterial activity against common pathogens and gut microbes. We then designed alkyne-bearing PCB probes for use in chemical proteomics target deconvolution studies. Target identification and validation revealed the cysteine protease legumain (also known as asparaginyl endopeptidase, AEP) to be a target of PCB. Inhibition of this target may account for PCB's diverse reported biological activities.

Phycocyanin improved alcohol-induced hepatorenal toxicity and behavior impairment in Wistar rats.

The aim of this study was to investigate a potential preventive effect of phycocyanin extract from Spirulina platensis against ethanol- induced hepatorenal toxicity and cognitive behavior impairment in male Wistar rats. The animals were randomly and equally divided into four groups (six animals each): control group received saline solution, ethanol (EtOH) group was injected intraperitoneally with 1 ml/kg of ethanol solution 38% (w/v), phycocyanin groups were treated with 25 (PC1) or 50 (PC2) mg/kg phycocyanin extract followed by ethanol administration. All treatments were conducted for 14 successive days. Results revealed that ethanol induced oxidative stress in brain, liver, and kidney by increasing lipid peroxidation level and SOD and CAT activities. Serum biochemical perturbations were also observed in EtOH group, which was indicated by a significant elevation in ALT, AST, cholesterol, triglycerides, creatinine, and urea levels. Combined exposure to EtOH with phytocyanin contracted these biochemical alterations. Phycocyanin decreased also EtOH-induced anxiety and ameliorated exploratory behavior assessed by the elevated-plus maze and open field tests respectively.

Combination of Phycocyanin, Zinc, and Selenium Improves Survival Rate and Inflammation in the Lipopolysaccharide-Galactosamine Mouse Model.

Sepsis is related to systemic inflammation and oxidative stress, the primary causes of death in intensive care units. Severe functional abnormalities in numerous organs can arise due to sepsis, with acute lung damage being the most common and significant morbidity. Spirulina, blue-green algae with high protein, vitamins, phycocyanin, and antioxidant content, shows anti-inflammatory properties by decreasing the release of cytokines. In addition, zinc (Zn) and selenium (Se) act as an antioxidant by inhibiting the oxidation of macromolecules, as well as the inhibition of the inflammatory response. The current study aimed to examine the combined properties of Zn, Se, and phycocyanin oligopeptides (ZnSePO) against lipopolysaccharide-D-galactosamine (LPS-GalN)-induced septic lung injury through survival rate, inflammatory, and histopathological changes in Balb/c mice. A total of 30 mice were allocated into three groups: normal control, LPS-GalN (100 ng of LPS plus 8 mg of D-galactosamine), LPS-GalN + ZnSePO (ZnPic, 52.5 µg/mL; SeMet, 0.02 µg/mL; and phycocyanin oligopeptide (PO), 2.00 mg/mL; at 1 h before the injection of LPS-GalN). Lung tissue from mice revealed noticeable inflammatory reactions and typical interstitial fibrosis after the LPS-GalN challenge. LPS-GalN-induced increased mortality rate and levels of IL-1, IL-6, IL-10, TGF-ß, TNF-α, and NF-κB in lung tissue. Moreover, treatment of septic mice LPS-GalN + ZnSePO reduced mortality rates and inflammatory responses. ZnSePO considerably influenced tissue cytokine levels, contributing to its capacity to minimize acute lung injury (ALI) and pulmonary inflammation and prevent pulmonary edema formation in LPS-GalN-injected mice. In conclusion, ZnSePO treatment enhanced the survival rate of endotoxemia mice via improving inflammation and oxidative stress, indicating a possible therapeutic effect for patients with septic infections.

Novel intelligent films containing anthocyanin and phycocyanin for nondestructively tracing fish spoilage.

Potential pH-responsive films were developed based on incorporating anthocyanin, phycocyanin, and a mixture of anthocyanin-phycocyanin (at a ratio of 3:1 v/v) within composite gelatin (1.5 g / 100 g film solution)/soybean polysaccharide (2.5 g / 100 g film solution) matrices. FTIR and SEM assessments certified the incorporation of the pigments into the film matrices. All the colorimetric films were highly sensitive when exposed to headspace ammonia, except the phycocyanin-incorporated film. Moreover, the fabricated intelligent films were conducted to trace the spoilage process of grass carp. An obvious relationship between the color (L*, a*, b*, ΔE) of indicators and pH, TVB-N, bacterial growth, ATP-related compounds, and K-value of the fish was observed. The film incorporated with mixed Ipomoea nil extract and phycocyanin possessed the best color variations (dark orange, pink, dark blue) with the degree of fish spoilage. Therefore, this intelligent film can be considered a promising sensor for monitoring fish freshness non-destructively.

Investigation of the Potential of Selected Food-Derived Antioxidants to Bind and Stabilise the Bioactive Blue Protein C-Phycocyanin from Cyanobacteria Spirulina.

Blue C-phycocyanin (C-PC), the major Spirulina protein with innumerable health-promoting benefits, is an attractive colourant and food supplement. A crucial obstacle to its more extensive use is its relatively low stability. This study aimed to screen various food-derived ligands for their ability to bind and stabilise C-PC, utilising spectroscopic techniques and molecular docking. Among twelve examined ligands, the protein fluorescence quenching revealed that only quercetin, coenzyme Q10 and resveratrol had a moderate affinity to C-PC (Ka of 2.2 to 3.7 × 105 M-1). Docking revealed these three ligands bind more strongly to the C-PC hexamer than the trimer, with the binding sites located at the interface of two (αß)3 trimers. UV/VIS absorption spectroscopy demonstrated the changes in the C-PC absorption spectra in a complex with quercetin and resveratrol compared to the spectra of free protein and ligands. Selected ligands did not affect the secondary structure content, but they induced changes in the tertiary protein structure in the CD study. A fluorescence-based thermal stability assay demonstrated quercetin and coenzyme Q10 increased the C-PC melting point by nearly 5 °C. Our study identified food-derived ligands that interact with C-PC and improve its thermal stability, indicating their potential as stabilising agents for C-PC in the food industry.

[Modified method for obtaining phycocyanine concentrate of Arthrospira platensis biomass].

The biomass of Arthrospira platensis cyanobacteria is a source of bioactive compounds such as chlorophylls, carotenoids, and, particularly, phycobiliproteins: C-phycocyanin and allophycocyanin. The wide range of biological activity shown by extracts with a high content of phycocyanins determines the prospects for their use as dietary supplements and ingredients of special foods. For food purposes, the degree of purity of phycocyanin concentrates, determined by the ratio of optical densities of their aqueous solutions at two wavelengths, namely D620/D280, must be greater than 0.7. Most methods for obtaining phycocyanin concentrates include laborious steps of fractional ammonium sulphate precipitation of protein from A. platensis biomass extracts followed by removal of salts solution. The use of membrane technology, specifically microfiltration, makes it possible to significantly intensify and simplify the process of obtaining phycocyanin concentrates. The aim of this research was to modify the method for obtaining a high-purity A. platensis phycocyanin concentrate by replacing the stage of ammonium sulfate precipitation of the protein by ultrafiltration of the extract followed by microfiltration. Material and methods. A sample of dry A. platensis biomass was used as a feedstock. Extraction of A. platensis biomass was carried out at a temperature of +40 °C for 3 h, the resulting suspension was centrifuged, and the supernatant was separated from the sediment. The obtained extract was subjected to ultrafiltration (membrane with a pore diameter of 30 kDa) followed by removal of the permeate containing low molecular weight impurities. The retentate was subjected to microfiltration (membrane with a pore size of 0.2 µm), concentrated by reverse osmosis and freeze-dried. Results. The content of C-phycocyanin and allophycocyanin in the dry concentrate was 42.0±1.3 and 7.0±0.3%, respectively, the degree of purity was 1.98. Conclusion. The scheme for obtaining A. platensis phycocyanin concentrate has been modified. A concentrate was obtained with a high degree of purity, allowing its use in food.

C-Phycocyanin and Lycium barbarum Polysaccharides Protect against Aspirin-Induced Inflammation and Apoptosis in Gastric RGM-1 Cells.

Aspirin causes gastrotoxicity and damaged epithelial defense via cyclooxygenase inhibition. C-phycocyanin (CPC) and Lycium barbarum polysaccharides (LBP), an active ingredient of Spirulina platensis and wolfberry, respectively, exerted antioxidation, anti-inflammation, and/or immunoregulation. The actions of CPC and/or LBP on gastric damage induced by aspirin were explored in rat gastric mucosal RGM-1 cells. Gastric injury was performed by 21 mM aspirin for 3 h after the pretreatment of CPC and/or LBP (100-500 µg/mL) for 24 h in RGM-1 cells. Proinflammatory, anti-inflammatory, and apoptotic markers were examined by ELISA or gel electrophoresis and Western blotting. Cell viability and interleukin 10 (IL-10) were reduced by aspirin. Increased proinflammatory markers, caspase 3 activity, and Bax protein were observed in RGM-1 cells with aspirin treatment. Aspirin elevated nuclear factor-κB (NF-κB), extracellular signal-regulated kinase (ERK), p38, and c-Jun N-terminal kinase (JNK) activation, while CPC and/or LBP increased IL-10, and attenuated proinflammatory markers, Bax protein, NF-κB, and the activation of ERK and JNK. Therefore, CPC and/or LBP possess anti-inflammation by restraining the activation of the ERK signaling pathway, and LBP decreases apoptosis by suppressing the JNK signaling pathway activation in gastric RGM-1 cells with aspirin-induced epithelial damage.

Iron Content, Iron Speciation and Phycocyanin in Commercial Samples of Arthrospira spp.

Cyanobacteria are characterized by high iron content. In this research, we collected ten commercial samples of Arthrospira spp. sold as food supplement to determine iron content and assess whether iron speciation showed variability among samples and changed respect to A. platensis grown in controlled conditions. Particular attention was also paid to phycocyanin, as an iron-binding protein. In six of the ten samples, 14 essential and non-essential trace elements were analysed using ICP-MS. Iron content measured in samples using atomic absorption spectrometry (AAS) varied from 353 (sample S5) to 1459 (sample S7) µg g-1 dry weight and was in the range of those reported by other authors in commercial supplements. Iron speciation was studied using size exclusion chromatography followed by the analysis of the collected fraction for the determination of iron by AAS and for protein separation using SDS-PAGE. Overlapping chromatographic profiles were obtained for total proteins, phycocyanin and iron, although quantitative differences were evidenced among the samples analysed. In most samples, iron was mainly bound to ligands with high molecular mass; however, in four samples iron was also bound to ligands with low molecular mass. In fractions containing the most relevant iron burden, the principal protein was phycocyanin, confirming its role as an iron-binding protein in commercial samples.

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.

Trends and Technological Advancements in the Possible Food Applications of Spirulina and Their Health Benefits: A Review.

Spirulina is a kind of blue-green algae (BGA) that is multicellular, filamentous, and prokaryotic. It is also known as a cyanobacterium. It is classified within the phylum known as blue-green algae. Despite the fact that it includes a high concentration of nutrients, such as proteins, vitamins, minerals, and fatty acids-in particular, the necessary omega-3 fatty acids and omega-6 fatty acids-the percentage of total fat and cholesterol that can be found in these algae is substantially lower when compared to other food sources. This is the case even if the percentage of total fat that can be found in these algae is also significantly lower. In addition to this, spirulina has a high concentration of bioactive compounds, such as phenols, phycocyanin pigment, and polysaccharides, which all take part in a number of biological activities, such as antioxidant and anti-inflammatory activity. As a result of this, spirulina has found its way into the formulation of a great number of medicinal foods, functional foods, and nutritional supplements. Therefore, this article makes an effort to shed light on spirulina, its nutritional value as a result of its chemical composition, and its applications to some food product formulations, such as dairy products, snacks, cookies, and pasta, that are necessary at an industrial level in the food industry all over the world. In addition, this article supports the idea of incorporating it into the food sector, both from a nutritional and health perspective, as it offers numerous advantages.