Search Results (73)

Spirulina’s (Arthrospira platensis) use in food applications is limited by its dark color and sulfurous odor. This study aimed to develop a preharvest bioprocessing strategy using Saccharomyces cerevisiae co-cultivation to address these limitations. At a yeast/microalgae biomass ratio of 10:1000 with 5 g/L of glucose supplementation, co-cultivation for 24 h induced a rapid color transition from dark blue–green to light green and imparted “floral–fruity” aromas. Major bioactive compounds, including β-carotene, linoleic acid, and γ-linolenic acid, increased significantly, while volatile sulfur compounds were eliminated. Chlorophyll a and carotenoid contents rose by over two fold, reflecting enhanced photosynthetic efficiency. Mechanistic analyses revealed that yeast-derived acetic acid upregulated genes involved in flavor precursor biosynthesis and promoted biomass accumulation. This strategy integrates sensory improvement with nutritional enhancement, providing a sustainable approach for developing spirulina-based functional foods. Full article

Perennial wall rocket (Diplotaxis tenuifolia L.—DC.) exhibits genotype-dependent responses to biostimulant applications, which have not yet been deeply investigated. A two-year greenhouse factorial experiment was carried out to assess the interactions between five cultivars (Mars, Naples, Tricia, Venice, and Olivetta), three biostimulant formulations (Cystoseira tamariscifolia L. extract; a commercial legume-derived protein hydrolysate, “Dynamic”; and Spirulina platensis extract) plus an untreated control, and three crop cycles (autumn, autumn–winter, and winter) on leaf yield and dry matter, organic acids, colorimetric parameters, hydrophilic and lipophilic antioxidant activities, nitrate concentration, nitrogen use efficiency, and mineral composition, using a split plot design with three replicates. Protein hydrolysate significantly enhanced yield and nitrogen use efficiency in Mars (+26%), Naples (+25.6%), Tricia (+25%), and Olivetta (+26%) compared to the control, while Spirulina platensis increased the mentioned parameters only in Venice (+36.2%). Nitrate accumulation was reduced by biostimulant application just in Venice, indicating genotype-dependent nitrogen metabolism responses. The findings of the present research demonstrate that the biostimulant efficacy in perennial wall rocket is mainly ruled by genotypic factors, and the appropriate combinations between the two mentioned experimental factors allow for optimization of leaf yield and quality while maintaining nitrate concentration under the regulation thresholds. Full article

A new spherification of Spirulina (Arthrospira platensis) was developed for its use as a food supplement. The novelty of this study is the incorporation of fresh Spirulina biomass into alginate spheres formulated with 3% sodium alginate and 1.5% calcium lactate and its addition into yogurt. The spheres and the fortified yogurt were stored at 4 °C for 15 days. The viability of Spirulina, either in contact with the yogurt or not, was evaluated both by OD_550nm measurements and microscopic observations. Furthermore, the effect of Spirulina spheres on Streptococcus thermophilus and Lactobacillus bulgaricus was evaluated by enumerating them in standard media. Spirulina retained its viability for up to 15 days when stored separately from the yogurt matrix. Spirulina had a stimulating effect on the lactic acid bacteria: after 15 days, L. bulgaricus and S. thermophilus showed a load increase of 2.66% and 1.64%, respectively, compared to the load detected in the unfortified yogurt. Our study has demonstrated the technical feasibility of producing fresh Spirulina spheres, which can be used alone or added to food preparation. Nevertheless, additional investigations—including quantitative assessment of bioactive compounds and comprehensive sensory analysis—are essential to validate the methodology and support its scalability. Full article

This study aimed to improve the quality characteristics of coated beef meatballs with Spirulina platensis, optimize its usage level and storage, and reduce the levels of carcinogenic polycyclic aromatic hydrocarbons (PAHs) in the product. Six groups of coated meatball samples were prepared with S. platensis powder at levels of 0.2–2.3% and 0% (control) and stored at −20 °C for 102 days. All ratios of S. platensis significantly increased the protein content and reduced the oxidation and all the PAH-compound and ΣPAH4 contents of the samples (p < 0.05). The sensory characteristics of the samples were improved by higher levels of S. platensis at later periods of storage. Using S. platensis resulted in significant decreases in the ΣPAH4 content of 16.21% and 39.53% in the samples with 1.25% and 2.3%, respectively (p < 0.05). The recommended solution that ensured the highest level of response optimization, with the highest “Desirability” among the top five solutions in terms of color (L*, a*, b*), overall acceptance, and flavor, was determined to be the solution with a S. platensis powder usage level of 1.25% and a storage period of 60 days. Consequently, S. platensis, which is considered to be a food of the future, improved the quality characteristics of coated meatballs and reduced their PAH level. Full article

Spirulina (Arthrospira platensis) is a microalga widely used as a dietary supplement in sports nutrition and in treating metabolic diseases such as diabetes, obesity and metabolic syndrome. Spirulina’s cell structure limits digestibility and reduces the availability of bioactive compounds. The extraction processes, coupled with encapsulation, can enhance the bioavailability of nutritional and antioxidant compounds, protecting them from degradation, preserving their functional activity, and supporting controlled release. The physicochemical properties of liposomes (Lps), bilosomes (Bls), and gelatin-enriched bilosomes (G-Bls) with incorporated Spirulina extracts were investigated. The delivery systems exhibited small particle size (101.8 ± 0.5 to 129.7 ± 1.2 nm), homogeneous distribution (polydispersity index (PDI) 0.17 ± 6.67 to 0.33 ± 9.06), negative surface charges (−31.9 ± 5.2 to 31.1 ± 6.4 mV), and high entrapment efficiency (>80%). G-Bls demonstrated effective retention of the extract, with a low release rate at pH 1.2 (41.8% ± 6.1) and controlled release at pH 7.0 (52.5% ± 3.0). Biocompatibility studies on Caco-2 cells showed that G-Bls maintained high cell viability at 200 μg·mL⁻¹ (87.89% ± 10.35) and significantly mitigated H₂O₂-induced oxidative stress at 20 and 200 μg·mL⁻¹, increasing cell viability by 23.47% and 19.28%. G-Bls are a promising delivery system for enhancing the stability, bioavailability, and protective effects of Spirulina extracts, supporting their potential application in dietary supplements aimed at promoting sports performance and recovery, mitigating exercise-induced oxidative stress, and managing metabolic disorders. Full article

This study evaluated the combined application of biochar (BC) and Spirulina platensis (SP) as a sustainable strategy to improve soil quality and salinity tolerance in mint (Mentha longifolia L.) cultivated in sandy soils. A pot experiment was conducted using saline irrigation water (5 dS m⁻¹) with four treatments: control, BC alone, SP alone, and BC + SP applied at 1% (w/w), arranged in a randomized complete block design with three replicates. Salt stress reduced plant height and biomass yield by 16% and 27%, respectively, and increased sodium (Na⁺) in shoots by 74%, causing ionic imbalance and decreased soil microbial biomass carbon by 19%. The combined BC + SP treatment significantly improved soil microbial biomass carbon (SMBC) by 100%, reduced soil Na⁺ by 41%, and enhanced K⁺/Na⁺ and Ca²⁺/Na⁺ ratios by 138% and 133%, respectively. Under salinity, BC + SP increased nutrient concentrations in mint shoots, including N (120%), P (106%), K (88%), Ca (67%), Fe (70%), Mn (50%), Zn (44%), and Cu (70%), and improved leaf chlorophyll content. These results demonstrate that BC and SP synergistically mitigate salinity stress by improving soil properties, nutrient uptake, and ionic balance, making BC + SP a promising sustainable amendment for saline sandy soils. Full article

Arthrospira platensis (spirulina) is a cyanobacterium containing various phytochemical compounds associated with various antioxidant, antimicrobial, antiviral, anticancer, anti-inflammatory, and immune-promoting properties. The efficacy of ethanolic and methanolic crude extracts of A. platensis regarding antibacterial, antioxidant, and anticancer effects was determined in this study. The ethanolic extract showed the highest antioxidant activity by 8.96 ± 0.84 mg gallic acid equivalent per gram of extract (mg GAE/g extract), 53.03 ± 4.21 mg trolox equivalent antioxidant capacity per gram of extract (mg TEAC/g extract), and 48.06 ± 0.78 mg TEAC/g extract as determined by DPPH, ABTS, FRAP assays, respectively. Moreover, the ethanolic extract showed the highest total phenolic and flavonoid compound contents by 38.79 ± 1.61 mg GAE/g extract and 27.50 ± 0.53 mg of quercetin equivalent per gram of extract (mg QE/g extract). Gallic acid and quercetin in the extracts were also determined by HPLC. The antibacterial activity was evaluated by agar well diffusion and broth dilution methods on skin pathogenic bacteria, including Staphylococcus aureus, Staphylococcus epidermidis, methicillin-resistant S. aureus (MRSA), Micrococcus luteus, Pseudomonas aeruginosa, and Cutibacterium acnes. The inhibition zone of A. platensis extracts ranges from 9.67 ± 0.58 to 12.50 ± 0.50 mm. In addition, MIC and MBC values ranged from 31.25 to 125 mg/mL. The inhibition of biofilm formation and biofilm eradication by A. platensis ethanolic extract was 87.18% and 99.77%, as determined by the crystal violet staining assay. Furthermore, the anticancer activity of A. platensis on A375 human melanoma cells was examined. The ethanolic and methanolic extracts induced DNA apoptosis through both intrinsic and extrinsic pathways by upregulating the expression of caspase-3, caspase-8, and caspase-9. These findings suggested that A. platensis demonstrated promising antioxidant, antibacterial, and anticancer activities, emphasizing its potential as a natural therapeutic agent for the management of pathological conditions. Full article

Sustainable bio-based products derived from fermentation are gaining increasing interest. The present study was designed to determine the interaction of Lacticaseibacillus rhamnosus 23.2 bacteria with spirulina in a 3 L glass bioreactor and the effect of aeration and agitation speed on the final product biomass and antioxidant capacity. The fermentation medium contained only glucose, an inorganic salt mixture, and spirulina powder. The estimated biomass and antioxidant activity were found to be 3.74 g/L and 84.72%, respectively, from the results of the optimization model. Scale-up was performed with the obtained optimization data, and three pilot-scale fermentations were carried out in a 30 L stainless steel bioreactor. As a result of pilot production, the obtained bioactive products were freeze-dried, and their antibacterial, antioxidant, total phenolic properties, and cytotoxic activity were investigated. The pilot production results showed that the increase in bacterial cell number was around 3–4 log after 24 h of fermentation. An inhibitory effect against pathogenic bacteria was observed. A strong radical scavenging effect was found in antioxidant analyses. Total phenolic substance content was 26.5 mg gallic acid equivalent (GAE) g⁻¹, which was the highest level in this study. Cytotoxic activity showed that bioactive products had a cytotoxic effect against Caco-2 adenocarcinoma cells. This study emphasizes the potential of Arthrospira platensis biomass as a substrate for the production of lactic acid bacteria (LAB)-based bioproducts. It is thought that the results obtained from this study may position potential innovative strategies in the food, pharmaceutical, agriculture, and cosmetic industries. Full article

The experiments in this study investigated the toxicity of naphthenic acids (NAs) on the algal culture Spirulina platensis. The tests monitored the progression of the algal suspension in media contaminated with various concentrations of naphthenic acids. The evolution of the algal culture during the metabolism of NAs was investigated. The monitoring also included the determination of the values of some parameters during the biodegradation process (pH, conductivity, cell viability, dissolved oxygen). Optical density measurements (OD₆₀₀) were used to quantify the growth of Spirulina platensis, alongside the determination of the sedimentation index (IS). Cell viability was assessed microscopically using TEM and optical microscopy. The results facilitated the estimation of the percentage of cell growth inhibition and the inhibitory concentration value, determined by estimating ECb50 (concentration of NAs corresponding to 50% inhibition). The chemical quantification of naphthenic acids in the samples analyzed was performed by calculating the acidity value (AV) and characterizing the naphthenic acids through FTIR analysis. The graphical representation of ECb50 was established by extrapolating to a concentration of 110 mg/mL of naphthenic acids. We have demonstrated that pollution caused by NAs can be mitigated by the algae Spirulina platensis, which can metabolize these compounds and thus biodegrade them. Full article

Microalgae are a promising source of bioactive compounds, particularly proteins and peptides, with potential applications in skin health and the cosmetic industry. This study investigated the antioxidant and anti-aging properties of peptide fractions derived from Spirulina platensis and Chlorella vulgaris. Both microalgae were cultivated, and their proteins were subsequently extracted, enzymatically hydrolyzed with alcalase, and fractionated through ultrafiltration. Alkaline extraction yielded 82% protein from S. platensis and 72% from C. vulgaris. Enzymatic hydrolysis predominantly yielded <3 kDa peptides, which exhibited strong antioxidant activity reaching 78% for 2,2-diphenyl-1-picrylhidrazol (DPPH), 82% for 2,2′-azinobis-3-etilbenzothiazoline-6-sulfonic acid (ABTS), and 74% for ferric reducing antioxidant power (FRAP), with IC₅₀ values as low as 23.44 µg/mL for ABTS inhibition in C. vulgaris. These peptides also significantly inhibited skin-aging enzymes, showing 84% inhibition of elastase, 90% of collagenase, and 66% of tyrosinase. Mass spectrometry and GNPS molecular networking of the <3 kDa fraction identified several di- and tri-peptides, including Lys-Val, Val-Arg, His-Ile, Lys-Leu, Ile-Leu, and Leu-Phe, Tyr-Phe, and Leu-Gly-Leu, potentially contributing to these bioactivities. These findings suggest that the enzymatic hydrolysis of S. platensis and C. vulgaris proteins provides a sustainable and natural source of bioactive peptides for antioxidant and anti-aging applications in food, pharmaceutical, and cosmetic industries. Full article

This study aimed to develop and characterize biodegradable films made from pectin, pomegranate seed oil, and different microalgae (Spirulina platensis, Chlorella sp., and Scenedesmus obliquus) and to evaluate their applicability as packaging by verifying their effect on the conservation and postharvest quality of cajarana (Spondias dulcis). The films proposed in this study were assessed for their physical, optical, and mechanical attributes, as well as the physicochemical characteristics of the fruits coated with the films after 14 days of storage at 10 ± 1 °C and relative humidity of 60 ± 5%. Incorporating microalgae improved the homogeneity and mechanical properties, decreasing breaking stress, elastic modulus, and maximum tensile strength, contributing to a lower solubility and improving the barrier properties of the films compared to the control (T1). The film formulated with 6% citric pectin, 40% glycerin, 0.5 mL·L⁻¹ pomegranate seed oil (PSO), and 0.05% Scenedesmus obliquus showed better performance in solubility, water vapor permeability (WVP), and mechanical properties, maintaining gloss and transparency, approaching the performance of the commercial PVC film. The film was formulated with 6% pectin + 40% glycerin + 0.5 mL·L⁻¹ PSO + 0.05% Chlorella sp. maintained the postharvest quality of cajarana fruits, allowing the conservation of the physicochemical quality of the fruits after 14 days of storage at 10 ± 1 °C and 60 ± 5% RH. Full article

Spirulina platensis is a promising microalga, but biomass harvesting remains a challenge. Fungal bioflocculation offers a potential solution, facilitating the production of valuable bioproducts like bioethanol. Effective cell disruption methods, including physical-chemical and enzymatic treatments, can enhance biomass utilization. However, commercial enzymes are not optimized for microalgae, necessitating research on ideal operational conditions. This study evaluated physical and enzymatic processes to hydrolyze bioflocculated microalgae for bioethanol production. The microalga was harvested using a fungal bioflocculant produced via submerged fermentation. Biomass hydrolysis involved physical methods (autoclaving, ultrasound + autoclaving, ultrasound + gelatinization, and gelatinization) combined with enzymes (amylase, amyloglucosidase, cellulase, and xylanase), optimized for pH, temperature, and enzyme load. Hydrolysates were then used for bioethanol production. Results showed a microalgae harvest efficiency of 99.7% with a 1:8 fungus-to-microalgae ratio. Enzyme optimization identified ideal conditions (e.g., pH 4.5; 60 °C for amylase/amyloglucosidase, 70 °C for cellulase, and 50 °C for xylanase). Combined enzymatic treatments achieved approximately 70% hydrolysis efficiency, yielding 19.06 g/L glucose and 7.29 g/L ethanol (~79% conversion). Ethanol productivity was ~0.6 g per 1 g bioflocculated biomass L⁻¹·hr. These findings highlight the potential of enzymatic hydrolysis for complex biomasses, although further studies are needed to refine enzyme applications for better biomass utilization. Full article

This study aimed to detect an impact of water–ethanol extracts of different microalgae species—Spirulina platensis, Dunaliella salina and Chlorella vulgaris—on the accumulation of bioactive compounds in tomatoes. A treatment with the corresponding ethanol solution and pure drinking water was used as a control. Tomato cultivar ‘Belle’ F1 (Enza Zaden) was grown in a polycarbonate greenhouse, in 25 L pots filled with a peat substrate (pH KCl 5.5). The plants were sprayed weekly from germination until the start of harvesting, in total nine times. Fruits were analysed at the stage of full ripeness. Bioactive compounds’ contents such as vitamin C, titratable acidity, pH value, β-carotene, lycopene, anthocyanin, total phenols as well as total soluble solids and dry matter were analysed, and the connection between fruit mass and the taste index was determined. The influence of the tested extracts on the bioactive compounds and quality parameters of tomatoes was different, but no significant differences for most of the analysed active compounds were found, with the exception of total phenols (from 137.59 ± 1.34 to 166.93 ± 2.01 mg 100 g⁻¹) and total soluble solids (from 3.93 ± 0.12 to 4.4 ± 0.18 °Brix). In the next research, a more detailed study about the influence of the ethanol concentration on changes in biologically active compounds should be provided. Full article

The cyanobacterium Limnospira platensis, vulgarly Spirulina, has gained significant attention due to its high protein content, rich bioactive compounds, and health benefits, making it a valuable resource in biotechnology, nutraceuticals, food supplements, biopharmaceuticals, and cosmetics. Recent advancements in fermentation technology have considerably improved the efficiency, scalability, and cost-effectiveness of L. platensis production while addressing environmental sustainability and enhancing product quality. Based on well-recognized databases (Google Scholar, PubMed, Scopus, Web of Science), this review explores the latest developments in L. platensis fermentation, emphasizing strain improvement, bioprocess engineering, and optimization of fermentation parameters. It also examines key factors such as bioreactor design, downstream processing, and innovative monitoring technologies aimed at maximizing biomass yield and bioactive compound production. Additionally, emerging applications of fermented L. platensis in various industries and future perspectives, including large-scale production, regulatory barriers, and biosafety considerations, are discussed. These insights provide a comprehensive outlook on the future of L. platensis fermentation in biotechnological applications. Full article

Cultured meat technology is a form of cellular agriculture where meat is produced from animal cells grown in a lab, instead of raising and slaughtering animals. This technology relies heavily on fetal bovine serum (FBS) in cell media; hence, production is costly and contributes significantly to ammonia and greenhouse gas emissions. Achieving the successful commercialization of cell-cultured food requires the critical resolution of manufacturing cost and safety concerns. Hence, our research efforts are focused on identifying commercially viable and ecologically sustainable alternatives to FBS. In this study, we evaluated the potential of twenty-six water-based algal and cyanobacterial extracts to stimulate cell growth for meat cultivation under 90% reduced serum conditions. The extracts were compared in viability, proliferation, and Trypan blue exclusion assays. In the first screening phase, the extracts were evaluated in a ZEM2S (zebrafish) cell culture in a 1% FBS regimen. Based on their ability to exhibit protein tolerance or promote cell proliferation, ten extracts were selected and further assayed in a QM7 cell culture. The QM7 cell line (myoblasts from Japanese quail) is highly relevant for meat cultivation because of its ability to differentiate into muscle fibers. Extracts derived from two microalgae species, Arthrospira platensis (Spirulina) and Dunaliella tertiolecta, demonstrated the highest tolerance in cell culture, above 10 μg/mL (expressed as total protein concentration). Tolerance at a 100 μg/mL concentration was demonstrated exclusively using an extract of blue spirulina (commercially purified Spirulina), which supported cell growth through multiple passages. Full article