Food and drug industry applications of microalgae Spirulina platensis: A review

Development of a spirulina feed effective only for the two larval stages of Schistosoma mansoni, not the intermediate host mollusc

BACKGROUND

Schistosomiasis control relies primarily on mass drug administration with praziquantel. However, persistent reinfection and high treatment costs remain significant challenges. Current strategies largely overlook intermediate host molluscs and infected larvae, which are critical sources of transmission. Niclosamide, the only widely used molluscicide, is limited by its high environmental toxicity and cost, creating a need for safer and more sustainable alternatives.

METHODS

In this study, we investigated the effects of a spirulina-based feed derived from the cyanobacterium Arthrospira platensis on infected snails. Laboratory experiments were conducted to assess the impact of spirulina on cercariae release from infected snails. We further examined the safety profile of spirulina by testing its effects on both snails and Japanese medaka. Additionally, the direct effects of spirulina constituents on cercariae viability were evaluated.

RESULTS

Snails fed spirulina presented a significant reduction in cercariae output, with reductions of up to 88%. The reduction was concentration dependent and more pronounced during the early stages of infection. Spirulina had no toxic effects on either snails or Japanese medakas. Further analysis revealed that the active ingredient causing the increase in mortality in cercaria was linoleic acid, a common ingredient in both the spirulina feed and the base feed, and a direct anti-parasitic effect of linoleic acid was confirmed.

CONCLUSION

Spirulina represents a promising, environmentally safe feed that can reduce the transmission of schistosomiasis by directly impacting schistosome larvae within infected snails and reducing the release of cercariae. This novel approach offers a sustainable and nontoxic alternative to current molluscicidal strategies and may contribute to more effective and environmentally friendly schistosomiasis control.

Comparison of Pressurized Water Extraction With Ultrasound Assisted Extraction for Isolation of Phycobiliproteins From Arthrospira platensis (Spirulina)

INTRODUCTION

Cyanobacterium Arthrospira platensis (AP) (Nordstedt) Gomont contains high content of phycobiliproteins (PBP), which are an important source for food industry. Methods effectively extracting proteins contained in AP cells are demanded to provide a supply of the material. Water-based extraction methods are advisable due to the high solubility of the PBP.

OBJECTIVES

Extraction techniques such as ultrasound assisted extraction (UAE) and pressurized water extraction (PWE) are popular due to their environmental friendliness, better extraction efficiency, and faster extraction process. In this paper, efficiency of the two methods is compared.

MATERIALS AND METHODS

PWE along with UAE is utilized for release of PBP from the AP cells. The extraction parameters including time, temperature, pressure, and ultrasound intensity are tested to obtain the most efficient setup. The methods were evaluated using sodium dodecyl sulfate polyacrylamide gel electrophoresis (SDS-PAGE), and the replicates of PWE extracts were further analyzed by capillary isoelectric focusing with laser-induced fluorescence (cIEF-LIF).

RESULTS

The developed PWE method using higher pressure treatment at lower temperature was significantly faster than UAE methods, and the SDS-PAGE results showed a high content of phycobiliproteins in the extracts. cIEF-LIF analysis showed that the sequential PWE of individual samples was repeatable, and the mild extraction provided a fluorescent profile similar to the commercially available C-phycocyanin standard.

CONCLUSION

Pressurized water extraction was shown to be an efficient, rapid, and well-automated extraction method for AP proteins in general, including bioactive phycobiliproteins. Obtained results encourage the use of PWE in small-scale analytical applications for primary extraction of proteins.

Deep Eutectic Solvents based green approach for bioactive molecules recovery from Spirulina

Spirulina is a unicellular microalga, characterized by blue/green color, that has received significant attention for its interesting nutritional composition. Phenolic compounds and phycocyanin (PC) are responsible for the many biological activities of Spirulina. Spirulina phenolic compounds are usually extracted using organic solvents, while PC is extracted with water or phosphate buffer solution, obtaining an extract characterized by low stability and low purity. Deep Eutectic Solvents (DESs) are green solvents, widely applied for bioactive molecules extraction, composed by two or more molecules which act as hydrogen bond acceptor or hydrogen bond donor to create an eutectic mixture. A Natural Deep Eutectic Solvent (NADES), is a DES composed only by natural compounds. This work aimed to optimize a green extraction procedure based on NADES to obtain an extract rich in phenolic compounds and PC from Spirulina. The application of NADESs as extraction solvents is an important strategy for recovering phenolic compounds and to increase and stabilize the protein PC. The optimized extraction procedure involved to use a betaine-glucose NADES under the following conditions: matrix-to-solvent ratio of 1:20 (w/w), temperature of 50 °C and one hour as extraction time. The developed extraction procedure guaranteed to recover a phenolic compounds and PC quantity of 11.77 ± 1.23 mg GAE (gallic acid equivalents) and 27.56 ± 2.46 g per g of Spirulina powder respectively. PC in the NADES extract degraded more slowly than in an aqueous extract. The extract phenolic compounds profile was determined through high performance liquid chromatography coupled with mass spectrometry analysis.

Role of gut microbiota in rheumatoid arthritis: Potential cellular mechanisms regulated by prebiotic, probiotic, and pharmacological interventions

Rheumatoid arthritis (RA) is a chronic autoimmune disease that primarily affects joints and multiple organs and systems, which is long-lasting and challenging to cure and significantly impacting patients' quality of life. Alterations in the composition of intestinal flora in both preclinical and confirmed RA patients indicate that intestinal bacteria play a vital role in RA immune function. However, the mechanism by which the intestinal flora is regulated to improve the condition of RA is not fully understood. This paper reviews the methods of regulating gut microbiota and its metabolites through prebiotics, probiotics, and pharmacological interventions, and discusses their effects on RA. Additionally, it explores the potential predictive role of cellular therapy mechanisms of intestinal flora in treating RA. These findings suggest that restoring the ecological balance of intestinal flora and regulating intestinal barrier function may enhance immune system function, thereby improving rheumatoid arthritis. This offers new insights into its treatment.

Recent Advancements in Production and Extraction Methods of Phycobiliprotein C-phycocyanin by Arthrospira (Spirulina) platensis: A Mini Review

Arthrospira platensis has been utilized as a food source since ancient times due to its rich nutrient profile. In recent years, its popularity as a dietary supplement has soared, especially due to the presence of a water-soluble phycobiliprotein, C-phycocyanin C (C-PC), which is abundant and notable for its fluorescent properties. C-PC contains the chromophore phycocyanobilin B (PCB-B), a tetrapyrrole molecule, that is why it plays a dual role as a food colorant and as nutraceutical. However, comprehensive studies have mostly evaluated C-PC's broader health-promoting properties, particularly its antioxidative and anti-inflammatory effects, which are linked to its ability to contrast oxidative stress and related pathological conditions. That is why this review explores recent advancements in optimizing culture conditions to enhance C-PC and PCB-B production, with a particular emphasis on novel extraction and purification techniques that increase yield and bioactivity. This focus on efficient production methods is crucial for expanding the commercial and therapeutic applications of C-PC, contributing to its growing relevance in the food and pharmaceutical industries.

Comprehensive Review of the Latest Investigations of the Health-Enhancing Effects of Selected Properties of Arthrospira and Spirulina Microalgae on Skin

Arthospira platensis and Spirulina platensis microalgae are a rich source of pro-health metabolites (% d.m.): proteins (50.0-71.3/46.0-63.0), carbohydrates (16.0-20.0/12.0-17.0), fats (0.9-14.2/6.4-14.3), polyphenolic compounds and phenols (7.3-33.2/7.8-44.5 and 4.2/0.3 mg GAE/g), and flavonoids (1.9/0.2 QUE/g) used in pharmaceutical and cosmetic formulations. This review summarises the research on the chemical profile, therapeutic effects in dermatological problems, application of Arthrospira and Spirulina microalgae, and contraindications to their use. The pro-health properties of these microalgae were analysed based on the relevant literature from 2019 to 2024. The antiviral mechanism of microalgal activity involves the inhibition of viral replication and enhancement of immunity. The anti-acne activity is attributed to alkaloids, alkanes, phenols, alkenes, phycocyanins, phthalates, tannins, carboxylic and phthalic acids, saponins, and steroids. The antibacterial activity generally depends on the components and structure of the bacterial cell wall. Their healing effect results from the inhibition of inflammatory and apoptotic processes, reduction of pro-inflammatory cytokines, stimulation of angiogenesis, and proliferation of fibroblasts and keratinocytes. The photoprotective action is regulated by amino acids, phlorotannins, carotenoids, mycosporins, and polyphenols inhibiting the production of tyrosinase, pro-inflammatory cytokines, and free oxygen radicals in fibroblasts and the stimulation of collagen production. Microalgae are promising molecular ingredients in innovative formulations of parapharmaceuticals and cosmetics used in the prophylaxis and therapy of dermatological problems. This review shows the application of spirulina-based commercial skin-care products as well as the safety and contraindications of spirulina use. Furthermore, the main directions for future studies of the pro-health suitability of microalgae exerting multidirectional effects on human skin are presented.

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.

Effect of Spirulina and Fish Processing By-Products Extracts on Citrinin-Induced Cytotoxicity in SH-SY5Y Cells

Citrinin (CIT) is a mycotoxin commonly found in grains, fruits, herbs, and spices. Its toxicity primarily affects the kidney and liver. Meanwhile, food industry by-products, particularly from fishing and aquaculture, contribute significantly to environmental concerns but can also serve as valuable sources of nutrients and bioactive compounds. Additionally, microalgae like spirulina (Arthrospira platensis) offer interesting high-added-value compounds with potential biological and cytoprotective properties. This study aims to reduce CIT's toxicity on SH-SY5Y cells using natural extracts from the microalgae spirulina and fish processing by-products (sea bass head). The combination of these extracts with CIT has shown increased cell viability up to 15% for fish by-products extract and about 10% for spirulina extract compared to CIT alone. Furthermore, a notable reduction of up to 63.2% in apoptosis has been observed when fish by-products extracts were combined with CIT, counteracting the effects of CIT alone. However, the extracts' effectiveness in preventing CIT toxicity in the cell cycle remains unclear. Overall, considering these nutrient and bioactive compound sources is crucial for enhancing food safety and mitigating the harmful effects of contaminants such as mycotoxins. Nevertheless, further studies are needed to investigate their mechanisms of action and better understand their protective effects more comprehensively.

Role of Arthrospira Platensis in Preventing and Treating High-Fat Diet-Induced Hypercholesterolemia in Adult Rats

Hyperlipidaemia is a recognised risk factor for cardiovascular disease. In this study, the antihyperlipidaemic properties of spirulina (Arthrospira platensis, strain S2 from Serbia) were tested in adult Wistar rats before and after induction of hypercholesterolaemia by a high-fat diet (HFD) to compare the preventive with the curative effect. Total cholesterol (TC), high-density lipoprotein cholesterol (HDL-C), low-density lipoprotein cholesterol (LDL-C), alanine transaminase (ALT) and aspartate transaminase (AST) levels were measured in the blood samples. The chemical composition (lipids, proteins and cholesterol) and the content of bile acids in the faeces of the animals were also analysed. Feeding rats with an atherogenic diet for 10 weeks led to the successful development of hyperlipidaemia, as serum TC and LDL-C levels as well as lipids, cholesterol and bile acids in the animals' faeces were significantly increased. Pre- and post-treatment with spirulina led to a reduction in serum LDL, TC and ALT levels. Administration of spirulina resulted in both a significant increase in primary bile acids excretion and a decrease in bile acids metabolism, with pre-treatment being more effective than post-treatment in some cases. These results suggest that increased excretion of bile acids as well as an effect on the gut microbiota may be the mechanism responsible for the anti-hyperlipidaemic activity of the tested spirulina strain.

Microalgae: A promising strategy for aflatoxin control in poultry feeds

Aflatoxins are toxic compounds produced by certain molds, primarily Aspergillus species, which can contaminate crops such as grains and nuts. These toxins pose a significant health risk to animals and humans. Aflatoxin B1 (AFB1) is the most potent of these compounds and has been well-characterized to lead to diminished growth and feed efficiency by disrupting nutrient absorption and metabolism in poultry. AFB1 can trigger apoptosis and inflammation, leading to a decline in immune function and changes in blood biochemistry in poultry. Recently, there has been growing interest in using microalgae as a natural antioxidant to mitigate the effects of aflatoxins in poultry diets. Microalgae have strong antioxidant, antimicrobial, anti-apoptotic, and anti-inflammatory properties, and adding them to aflatoxin-contaminated poultry diets has been shown to improve growth and overall health. This review investigates the potential of microalgae, such as Spirulina platensis, Chlorella vulgaris, and Enteromorpha prolifera, to mitigate AFB1 contamination in poultry feeds. These microalgae contain substantial amounts of bioactive compounds, including polysaccharides, peptides, vitamins, and pigments, which possess antioxidant, antimicrobial, and detoxifying properties. Microalgae can bind to aflatoxins and prevent their absorption in the gastrointestinal tract of poultry. They can also enhance the immune system of poultry, making them more resilient to the toxic effects of AFB1. Based on the data collected, microalgae have shown promising results in combating AFB1 contamination in poultry feeds. They can bind to aflatoxins, boost the immune system, and improve feed quality. This review emphasizes the harmful effects of AFB1 on poultry and the promising role of microalgae in reducing these effects.

Prefeeding of Clarias gariepinus with Spirulina platensis counteracts petroleum hydrocarbons-induced hepato- and nephrotoxicity

Petroleum aromatic hydrocarbons are considered one of the most dangerous aquatic pollutants due to their widespread across water bodies, persistence, and extension to the food chain. To our knowledge, there hasn't been any research investigating the hepatorenoprotective effects of Spirulina platensis (SP) against toxicity induced by these environmental toxicants in fish. Thus, we decided to explore its potential safeguarding against benzene and toluene exposure in adult Clarias gariepinus. To achieve this objective, fish were divided into five groups (60 per group; 20 per replicate). The first group served as a control. The second and third groups were intoxicated with benzene and toluene at doses of 0.762 and 26.614 ng/L, respectively for 15 days. The fourth and fifth groups (SP + benzene and SP + toluene, respectively) were challenged with benzene and toluene as previously mentioned following dietary inclusion of SP at a dose of 5 g/kg diet for 30 days. The marked increase in liver metabolizing enzymes, glucose, total protein, albumin, globulin, albumin/globulin ratio, and creatinine confirmed the hepato- and nephrotoxic impacts of benzene and toluene. These outcomes were coupled with cytopathological affections and excessive collagen deposition. The incorporation of SP in ration formulation, on the contrary, restored the previously mentioned toxicological profile due to its antioxidant and cytoprotective attributes. Regardless of SP intervention, the renal tissues still displayed histo-architectural lesions, because of insufficient dose and timeframe. Additional research will be required to identify the ideal SP remediation regimen.

Polysaccharides derived from Spirulina platensis inhibited Singapore grouper iridovirus by impeding the entry of viral particles

Attributable to the rapid dissemination and high lethality of Singapore grouper iridovirus (SGIV), it has caused significant economic losses for marine fish aquaculture in China and Southeast Asian nations. Hence, there is an urgent need to find antiviral drugs that are both safe and effective. In this study, a novel heteropolysaccharide named Spirulina platensis polysaccharides (SPP) was purified and characterized from S. platensis. The molecular weight of SPP is 276 kDa and it mainly consists of Glc and Rha, followed by minor components such as Gal, Xyl, and Fuc. The backbone of SPP was determined to be →2) -β-Rhap-(1 → 4) -α-Fucp-(1 → [2) -α-Rhap-(1] 2[→6)-α-Glcp-(1] 4[→ 4) -α-Glcp-(1] 8[→ 4) -β-Glcp-(1]2→, with branches of β-Galp, α-Xylp and α-Glcp. SPP significantly inhibited SGIV-induced cytopathic effects (CPEs), viral gene replication and viral protein expression. The antiviral mechanism of SPP was associated with the disruption of SGIV entry to host cells. Furthermore, it was not observed that SPP made statistically significant impact on the expression of interferon-related cytokines. Our results offered novel insights into the potential utilization of spirulina polysaccharides for combating aquatic animal viruses.

Sulfonated magnetic spirulina nanobiomaterial as a novel and environmentally friendly catalyst for the synthesis of dihydroquinazolin-4(1H)-ones in aqueous medium

Spirulina algae is an excellent candidate for catalyst preparation due to its reactive functional groups, cost-effectiveness, widespread commercial accessibility, and biodegradability. In this study, magnetized Spirulina was used for the synthesis of dihydroquinazolin-4(1H)-ones (DHQZs) as catalyst. Magnetized Spirulina was produced by CoFe2O4 and sulfonation method using chlorosulfonic acid to create the catalyst [CoFe2O4-Sp-SO3H]. It was affirmed by various techniques, including Fourier transform infrared (FT-IR), Vibrating sample magnetometry (VSM), Powder X-ray diffraction (XRD), Energy-dispersive X-ray spectroscopy (EDS), Thermogravimetric analysis (TGA), Transmission electron microscopy (TEM), Field emission scanning electron microscopy (FE-SEM), and elemental mapping techniques. DHQZs synthesis was accomplished through a concise one-pot, three-component reaction involving a range of diverse aldehydes, isatoic anhydride, and primary aromatic amine, within an aqueous medium. The method offers several advantages, including using green conditions, the generation of several new 2-furan-quinazolinone derivatives, chromatography-free purification, short reaction times, appropriate yield of product (75-96%), and catalyst recyclability. The proposed catalyst and water as solvent demonstrated a strong synergistic effect, leading to the prosperous synthesis of various novel dihydroquinazolinones at 60 °C. These numerous benefits make our approach highly attractive for academic research and industrial applications.

The Effects of Spirulina Supplementation on Cardiometabolic Risk Factors: A Narrative Review

Spirulina (Arthrospira platensis) is a cyanobacterium associated with multiple health benefits. Cardiometabolic diseases such as cardiovascular disease, nonalcoholic fatty liver disease, and diabetes are prevalent yet usually preventable non-communicable diseases. Modifiable risk factors for cardiometabolic diseases include excessive body weight, body inflammation, atherogenic lipid profile, and imbalanced glucose metabolism. This review explores the effects of spirulina on cardiometabolic diseases risk factors. Spirulina was effective in reducing body weight, body mass index, and waist circumference, with a potential dose-dependent effect. It also decreased interleukin 6, an important biomarker of body inflammation, by inhibiting NADPH oxidase enzyme, and lowering insulin resistance. spirulina supplementation also reduced triglycerides, low-density lipoprotein cholesterol, and increased high-density lipoprotein cholesterol. Additionally, spirulina reduced fasting blood sugar and post-prandial blood sugar and increased insulin sensitivity, but no effect was observed on glycated hemoglobin A1c. The diverse nutrients, such as phycocyanin, gamma-linolenic acid, and vitamin B12, present in spirulina contribute to its cardiometabolic benefits. The doses used are heterogeneous for most studies, ranging from 1 to 8 grams daily, but most studies administered spirulina for 3 months to observe an effect. The collective evidence suggests that spirulina supplements may help improve risk factors for cardiometabolic diseases, thus, preventing its development. However, due to the heterogeneity of the results, more randomized clinical trials are needed to draw robust conclusions about spirulina's therapeutic potential in ameliorating risk factors for cardiometabolic diseases and fully elucidate the mechanisms by which it exerts its effects.