Improvement of the growth of Arthrospira (Spirulina) platensis from Toliara (Madagascar): Effect of agitation, salinity and CO2 addition

Chemical Composition, Bioactivities, and Applications of Spirulina (Limnospira platensis) in Food, Feed, and Medicine

Spirulina (Limnospira platensis) is a microalga recognised for its rich nutritional composition and diverse bioactive compounds, making it a valuable functional food, feed, and therapeutic agent. This review examines spirulina's chemical composition, including its high levels of protein, essential fatty acids, vitamins, minerals, and bioactive compounds, such as the phycocyanin pigment, polysaccharides, and carotenoids, in food, feed, and medicine. These compounds exhibit various biological activities, including antioxidant, anti-inflammatory, immunomodulatory, antiviral, anticancer, antidiabetic and lipid-lowering effects. Spirulina's potential to mitigate oxidative stress, enhance immune function, and inhibit tumour growth positions it as a promising candidate for preventing chronic diseases. Additionally, spirulina is gaining interest in the animal feed sector as a promotor of growth performance, improving immune responses and increasing resistance to diseases in livestock, poultry, and aquaculture. Despite its well-documented health benefits, future research is needed to optimize production/cultivation methods, improve its bioavailability, and validate its efficacy (dose-effect relationship) and safety through clinical trials and large-scale human trials. This review underscores the potential of spirulina to address global health and nutrition challenges, supporting its continued application in food, feed, and medicine.

Effect of various light spectra on amino acids and pigment production of Arthrospira platensis using flat-plate photobioreactor

Today, the use of nutrients derived from natural bioactive compounds application in the food, pharmaceutical, and cosmetic industries is on the increase. This paper aimed to evaluate the amino acids profile (essential and non-essential) and pigments composition (chlorophyll a, carotenoids, and phycocyanin) of Arthrospira platensis (a blue-green microalga) cultivation in a flat-plate photobioreactor under various types of light-emitting diodes (red: 620-680 nm, white: 380-780 nm, yellow: 570-600nm, blue: 445-480 nm). The maximum biomass concentration (604.96 mg L-1) occurred when the red LED was applied for cultivation, and the minimum biomass concentration (279.39 mg L-1) was obtained under blue LED. The sequence of pigments and amino acids concentrations (mg L-1culture volume) was approximately in accordance with the biomass productivity. It means the red light produces the maximum concentration of pigments (chlorophyll a: 5.42, carotenoids: 2.92, phycocyanin: 67.54 mg L-1) and amino acids (essential amino acids: 110.47, nonessential amino acids: 179.10 mg L-1). Nevertheless, when these values were measured in mg per g of dry weight, the utmost contents were observed in microalgal products cultivated under blue LED. These consequences are due to the highest cell productivity and the most extended length of cells that occurred under red and blue LEDs, respectively.

Sustainable Production of Pigments from Cyanobacteria

Pigments are intensely coloured compounds used in many industries to colour other materials. The demand for naturally synthesised pigments is increasing and their production can be incorporated into circular bioeconomy approaches. Natural pigments are produced by bacteria, cyanobacteria, microalgae, macroalgae, plants and animals. There is a huge unexplored biodiversity of prokaryotic cyanobacteria which are microscopic phototrophic microorganisms that have the ability to capture solar energy and CO2 and use it to synthesise a diverse range of sugars, lipids, amino acids and biochemicals including pigments. This makes them attractive for the sustainable production of a wide range of high-value products including industrial chemicals, pharmaceuticals, nutraceuticals and animal-feed supplements. The advantages of cyanobacteria production platforms include comparatively high growth rates, their ability to use freshwater, seawater or brackish water and the ability to cultivate them on non-arable land. The pigments derived from cyanobacteria and microalgae include chlorophylls, carotenoids and phycobiliproteins that have useful properties for advanced technical and commercial products. Development and optimisation of strain-specific pigment-based cultivation strategies support the development of economically feasible pigment biorefinery scenarios with enhanced pigment yields, quality and price. Thus, this chapter discusses the origin, properties, strain selection, production techniques and market opportunities of cyanobacterial pigments.

Modeling and Optimizing the Effect of Light Color, Sodium Chloride and Glucose Concentration on Biomass Production and the Quality of Arthrospira platensis Using Response Surface Methodology (RSM)

Arthrospira platensis (Spirulina) biomass is a valuable source of sustainable proteins, and the basis for new food and feed products. State-of-the-art production of Spirulina biomass in open pond systems only allows limited control of essential process parameters, such as light color, salinity control, or mixotrophic growth, due to the high risk of contaminations. Closed photobioreactors offer a highly controllable system to optimize all process parameters affecting Spirulina biomass production (quantity) and biomass composition (quality). However, a comprehensive analysis of the impact of light color, salinity effects, and mixotrophic growth modes of Spirulina biomass production has not been performed yet. In this study, Response Surface Methodology (RSM) was employed to develop statistical models, and define optimal mixotrophic process conditions yielding maximum quantitative biomass productivity and high-quality biomass composition related to cellular protein and phycocyanin content. The individual and interaction effects of 0, 5, 15, and 30 g/L of sodium chloride (S), and 0, 1.5, 2, and 2.5 g/L of glucose (G) in three costume-made LED panels (L) where the dominant color was white (W), red (R), and yellow (Y) were investigated in a full factorial design. Spirulina was cultivated in 200 mL cell culture flasks in different treatments, and data were collected at the end of the log growth phase. The lack-of-fit test showed that the cubic model was the most suitable to predict the biomass concentration and protein content, and the two-factor interaction (2FI) was preferred to predict the cellular phycocyanin content (p > 0.05). The reduced models were produced by excluding insignificant terms (p > 0.05). The experimental validation of the RSM optimization showed that the highest biomass concentration (1.09, 1.08, and 0.85 g/L), with improved phycocyanin content of 82.27, 59.47, 107 mg/g, and protein content of 46.18, 39.76, 53.16%, was obtained under the process parameter configuration WL4.28S2.5G, RL10.63S1.33G, and YL1.00S0.88G, respectively.

Passively immobilized cyanobacteria Nostoc species BB 92.2 in a moving bed photobioreactor (MBPBR): design, cultivation and characterization

The cyanobacterium Nostoc sp. BB 92.3. had shown antibacterial activity. A cultivation as biofilm, a self-forming matrix of cells and extracellular polymeric substances, increased the antibacterial effect. A new photobioreactor system was developed that allows a surface-associated cultivation of Nostoc sp. as biofilm. High-density polyethylene carriers operated as a moving bed were selected as surface for biomass immobilization. This system, well established in heterotrophic wastewater treatment, was for the first time used for phototrophic biofilms. The aim was a cultivation on a large scale without inhibiting growth while maximizing immobilization. Cultivation in a small photobioreactor (1.5 L) with different volumetric filling degrees of carriers (13.4-53.8 %) in a batch process achieved immobilization rates of 70-85 % and growth was similar to a no-carrier-control. In a larger photobioreactor (65-liter) essentially all of the biomass was immobilized on the carriers and the space-time yield of biomass (0.018 g_{cell dry weight} L^-1 day^-1 ) was competitive compared to phototrophic biofilm cultivations from literature. The use of carriers increased the gas exchange in the reactor by a factor of 2.5-3, but doubled the mixing time. Enriched gassing with carbon dioxide resulted in a short-term increase in growth rate, but unexpectedly it also adversely changed the growth morphology. This article is protected by copyright. All rights reserved.

Effect of residence time in continuous photobioreactor on mass and energy balance of microalgal protein production

There is increasing interest in new protein sources for the food and feed industry and for the agricultural sector, and microalgae are considered a good alternative, having a high protein content and a well-balanced amino acid profile. However, protein production from microalgae presents several unsolved issues, as the biomass composition changes markedly as a function of cultivation operating conditions. Continuous systems, however, may be properly set to boost the accumulation of protein in the biomass, ensuring stable production. Here, two microalgae and two cyanobacterial species were cultivated in continuous operating photobioreactors (PBR) under nonlimiting nutrient conditions, to study the effects of light intensity and residence time on both biomass and protein productivity at steady state. Although light strongly affected biomass growth inside the PBR, the overall protein pool did not vary in response to irradiance. On the other hand, shorter residence times resulted in protein accumulation of up to 68 % in cyanobacteria, in contrast with green algae, where a minor influence of residence time on biomass composition was observed. Energy balance showed that light conversion to protein decreased with light intensity. Protein content was also related to energy costs for cell maintenance. In conclusion, it is shown that residence time is the key variable to increase protein content and yield of protein production, but its effect depends on the specific species.

Cultivation of Microalgae and Cyanobacteria: Effect of Operating Conditions on Growth and Biomass Composition

The purpose of this work is to define optimal growth conditions to maximise biomass for batch culture of the cyanobacterium Arthrospira maxima and the microalgae Chlorella vulgaris, Isochrysis galbana and Nannochloropsis gaditana. Thus, we study the effect of three variables on cell growth: i.e., inoculum:culture medium volume ratio (5:45, 10:40, 15:35 and 20:30 mL:mL), light:dark photoperiod (8:16, 12:12 and 16:8 h) and type of culture medium, including both synthetic media (Guillard’s F/2 and Walne’s) and wastewaters. The results showed that the initial inoculum:culture medium volume ratio, within the range 5:45 to 20:30, did not affect the amount of biomass at the end of the growth (14 days), whereas high (18 h) or low (6 h) number of hours of daily light was important for cell growth. The contribution of nutrients from different culture media could increase the growth rate of the different species. A. maxima was favoured in seawater enriched with Guillard’s F/2 as well as C. vulgaris and N. gaditana, but in freshwater medium. I. galbana had the greatest growth in the marine environment enriched with Walne’s media. Nitrogen was the limiting nutrient for growth at the end of the exponential phase of growth for C. vulgaris and N. gaditana, while iron was for A. maxima and I. galbana. The growth in different synthetic culture media also determines the biochemical composition of each of the microalgae. All species demonstrated their capability to grow in effluents from a wastewater treatment plant and they efficiently consume nitrogen, especially the three microalga species.

Bioproduct Potential of Outdoor Cultures of Tolypothrix sp.: Effect of Carbon Dioxide and Metal-Rich Wastewater

Rising CO2 levels, associated climatic instability, freshwater scarcity and diminishing arable land exacerbate the challenge to maintain food security for the fast growing human population. Although coal-fired power plants generate large amounts of CO2 emissions and wastewater, containing environmentally unsafe concentrations of metals, they ensure energy security. Nitrogen (N2)-fixation by cyanobacteria eliminate nitrogen fertilization costs, making them promising candidates for remediation of waste CO2 and metals from macronutrient-poor ash dam water and the biomass is suitable for phycocyanin and biofertilizer product development. Here, the effects of CO2 and metal mixtures on growth, bioproduct and metal removal potential were investigated for the self-flocculating, N2-fixing freshwater cyanobacterium Tolypothrix sp. Tolypothrix sp. was grown outdoors in simulated ash dam wastewater (SADW) in 500 L vertical bag suspension cultures and as biofilms in modified algal-turf scrubbers. The cultivation systems were aerated with air containing either 15% CO2 (v/v) or not. CO2-fertilization resulted in ∼1.25- and 1.45-fold higher biomass productivities and ∼40 and 27% increased phycocyanin and phycoerythrin contents for biofilm and suspension cultures, respectively. CO2 had no effect on removal of Al, As, Cu, Fe, Sr, and Zn, while Mo removal increased by 37% in both systems. In contrast, Ni removal was reduced in biofilm systems, while Se removal increased by 73% in suspension cultures. Based on biomass yields and biochemical data obtained, net present value (NPV) and sensitivities analyses used four bioproduct scenarios: (1) phycocyanin sole product, (2) biofertilizer sole product, (3) 50% phycocyanin and 50% biofertilizer, and (4) 100% phycocyanin and 100% biofertilizer (residual biomass) for power station co-located and not co-located 10 ha facilities over a 20-year period. Economic feasibility for the production of food-grade phycocyanin either as a sole product or with co-production of biofertilizer was demonstrated for CO2-enriched vertical and raceway suspension cultures raised without nitrogen-fertilization and co-location with power stations significantly increased profit margins.

Effects of shear stress on microalgae - A review

Cultivation of microalgae requires consideration of shear stress, which is generated by operations such as mixing, circulation, aeration and pumping that are designed to facilitate mass and heat transfer as well as light distribution in cultures. Excessive shear stress can cause increased cell mortality, decreased growth rate and cell viability, or even cell lysis. This review examines the sources of shear stress in different cultivation systems, shear stress tolerance of different microalgal species and the physiological factors and environmental conditions that may affect shear sensitivity, and potential approaches to mitigate the detrimental effects of shear stress. In general, green algae have the greatest tolerance to shear stress, followed by cyanobacteria, haptophytes, red algae, and diatoms, with dinoflagellates comprising the most shear-sensitive species. The shear-sensitivity of microalgae is determined primarily by cell wall strength, cell morphology and the presence of flagella. Turbulence, eddy size, and viscosity are the most prominent parameters affecting shear stress to microalgal cells during cultivation.

Production of lutein, and polyunsaturated fatty acids by the acidophilic eukaryotic microalga Coccomyxa onubensis under abiotic stress by salt or ultraviolet light

In this study, the effect of abiotic stress on the acidophilic eukaryotic microalga, Coccomyxa onubensis, was analyzed for the production of lutein and PUFAs (polyunsaturated fatty acids). It grows autotrophically at a pH of 2.5. It showed a growth rate of 0.30 d^-1, and produced approximately 122.50 mg·L^-1·d^-1 biomass, containing lipids (300.39 mg g^-1dw), lutein (5.30 mg g^-1dw), and β-carotene (1.20 mg g^-1dw). The fatty acid methyl ester (FAME) fraction was 89.70 mg g^-1dw with abundant palmitic acid (28.70%) and linoleic acid (37.80%). The addition of 100 mM NaCl improved the growth rate (0.54 d^-1), biomass productivity (243.75 mg·L^-1·d^-1), and lipids accumulation (416.16 mg g^-1dw). The microalga showed a lutein content of 6.70 mg g^-1dw and FAME fraction of 118.90 mg g^-1dw; 68% of the FAMEs were PUFAs. However, when 200-500 mM salt was added, its growth was inhibited but there was a significant induction of lutein (up to 7.80 mg g^-1dw). Under continuous illumination with PAR (photosynthetically active radiations) +UVA (ultraviolet A, 8.7 W m^-2), C. onubensis showed a growth rate of 0.40 d^-1, and produced 226.3 mg·L^-1·d^-1 biomass, containing lipids, (487.26 mg g^-1dw), lutein (7.07 mg g^-1dw), and FAMEs (232.9 mg g^-1dw); 48.4% of the FAME were PUFAs. The illumination with PAR + UVB (ultraviolet B, 0.16 W m^-2) was toxic for cells. These results indicate that C. onubensis biomass is suitable as a supplement for functional foods and/or source of high added value products.

Edible Cyanobacterial Genus Arthrospira: Actual State of the Art in Cultivation Methods, Genetics, and Application in Medicine

The cyanobacterial genus Arthrospira appears very conserved and has been divided into five main genetic clusters on the basis of molecular taxonomy markers. Genetic studies of seven Arthrospira strains, including genome sequencing, have enabled a better understanding of those photosynthetic prokaryotes. Even though genetic manipulations have not yet been performed with success, many genomic and proteomic features such as stress adaptation, nitrogen fixation, or biofuel production have been characterized. Many of above-mentioned studies aimed to optimize the cultivation conditions. Factors like the light intensity and quality, the nitrogen source, or different modes of growth (auto-, hetero-, or mixotrophic) have been studied in detail. The scaling-up of the biomass production using photobioreactors, either closed or open, was also investigated to increase the production of useful compounds. The richness of nutrients contained in the genus Arthrospira can be used for promising applications in the biomedical domain. Ingredients such as the calcium spirulan, immulina, C-phycocyanin, and γ-linolenic acid (GLA) show a strong biological activity. Recently, its use in the fight against cancer cells was documented in many publications. The health-promoting action of "Spirulina" has been demonstrated in the case of cardiovascular diseases and age-related conditions. Some compounds also have potent immunomodulatory properties, promoting the growth of beneficial gut microflora, acting as antimicrobial and antiviral. Products derived from Arthrospira were shown to successfully replace biomaterial scaffolds in regenerative medicine. Supplementation with the cyanobacterium also improves the health of livestock and quality of the products of animal origin. They were also used in cosmetic preparations.

Nutrients removal and recovery from saline wastewater by Spirulina platensis

As an important alternative to alleviate the pressure of fresh water shortage, seawater application is facing a great challenge on the wastewater treatment due to the salinity brought from seawater. Spirulina platensis originated from salty lake was used to treat mixed synthetic toilet flushing wastewater of seawater with washing wastewater of freshwater. It was showed that 79.96% of TN (to 15.69mg/L), 93.35% of TP (to 1.03mg/L) and 90.02% of COD_Cr (to 90.24mg/L) were removed with 0.76g/L of biomass production in the optimal ratio 7:3 of the above mixed synthetic wastewater. The performance was better than that of current strategy of seawater toilet flushing treatment. With the evaluation of nutrients uptake, biomass composition and microalgal aggregation, a model of nutrients recovery and metabolism of Spirulina platensis in saline wastewater treatment was proposed. It is provided a promising strategy for saline wastewater treatment with valuable biomass yield.

Optimization of production of C-phycocyanin and extracellular polymeric substances by Arthrospira sp

The key factors influencing the production of C-phycocyanin (C-PC) and extracellular polymeric substances (EPS) by photoautotrophic culture of Arthrospira sp. were optimized using Taguchi method. Six factors were varied at either three or two levels as follows: light intensity at three levels; three initial culture pHs; two species of Arthrospira; three concentrations of Zarrouk's medium; three rates of aeration of the culture with air mixed with 2% v/v carbon dioxide; and two incubation temperatures. All cultures ran for 14 days. The optimal conditions for the production of C-PC and EPS were different. For both products, the best cyanobacterium proved to be Arthrospira maxima IFRPD1183. The production of C-PC was maximized with the following conditions: a light intensity of 68 µmol photons m^-2 s^-1 (a diurnal cycle of 16-h photoperiod and 8-h dark period), an initial pH of 10, the full strength (100%) Zarrouk's culture medium, an aeration rate of 0.6 vvm (air mixed with 2% v/v CO₂) and a culture temperature of 30 °C. The concentration of Zarrouk's medium was the most important factor influencing the final concentration of C-PC. The optimal conditions for maximal production of EPS were as follows: a light intensity of 203 µmol photons m^-2 s^-1 with the earlier specified light-dark cycle; an initial pH of 9.5; a 50% strength of Zarrouk's medium; an aeration rate of 0.2 vvm (air mixed with 2% v/v CO₂); and a temperature of 35 °C. Production of C-PC and EPS in raceway ponds is discussed.

Heterotrophic Cultivation of Cyanobacteria: Study of Effect of Exogenous Sources of Organic Carbon, Absolute Amount of Nutrients, and Stirring Speed on Biomass and Lipid Productivity

The production of bioproducts from cyanobacteria with techno-economic feasibility is a challenge to these biotechnological processes. The choice of low-cost raw materials is of great importance for the overall economy of bioprocesses, as they represent a significant percentage in the final cost of the product. The objective of this work was to study the operational parameters of cultivation (exogenous sources of organic carbon and absolute amount of nutrients) to optimize productivity in bioproducts by Aphanothece microscopica Nägeli, for further evaluation of stirring speed. The experiments were performed in a bubble column bioreactor, operating at 30°C, pH of 7.6, C/N ratio of 20, 100 mg/L of inoculum, continuous aeration of 1 volume of air per volume of culture per minute (VVM), and absence of light. The results indicate that absolute amounts of 5,000/250 using cassava starch resulted in improved system performance, reaching biomass productivity of 36.66 mg/L/h in parallel with lipid productivity of 6.65 mg/L/h. Finally, experiments with variation in stirring speed indicate that 200 rpm resulted in better average rate of substrate consumption (44.01 mg/L/h), in parallel to biomass productivity of 39.27 mg/L/h. However, the increase of stirring speed had a negative effect on lipid productivity of the process. The technological route developed indicates potential to production of biomass and bulk oil, as a result of the capacity of cyanobacteria to adapt their metabolism in varying culture conditions, which provides opportunities to modify, control, and thereby maximize the formation of targeted compounds.

Producción de pigmentos procedentes de Arthrospira maxima cultivada en fotobiorreactores

El cultivo de cianobacterias, como Arthrospira, puede realizarse en sistemas abiertos y sistemas cerrados o fotobiorreactores. El objetivo de la presente investigación fue evaluar la producción de pigmentos de Arthrospira maxima cultivada en dos tipos de fotobiorreactores. El cultivo se realizó de forma discontinua (Batch) bajo ambiente controlado, en fotobiorreactores helicoidales y cilíndricos, durante 30 días, en medio Zarrouk. La determinación de los pigmentos se realizó en las fases de crecimiento exponencial y estacionario. Para los pigmentos liposolubles, la biomasa se sometió a extracción con acetona 90%, y posterior determinación por Cromatografía Líquida de Alta Eficiencia, y para la extracción de los pigmentos ficobiliproteínicos se ensayaron cuatro métodos: 1. regulador de fosfatos/enzimas; 2. solución alcalina, previo tratamiento con CaCl2; 3. buffer de fosfato, previo tratamiento con hielo seco y 4. agua (4ºC), y posterior determinación por Espectrofotometría UV-Visible. Los mayores valores de pigmentos liposolubles fueron obtenidos en los cultivos realizados en fotobiorreactor helicoidal durante la fase exponencial (clorofila a 11,08±0,006 µg mL-1; β-caroteno 1,82±0,003 µg mL-1; zeaxantina 0,72±0,002 µg mL-1); mientras que los mayores contenidos de los pigmentos ficobiliproteínicos se obtuvieron en fotobiorreactor cilíndrico, durante la fase estacionaria, utilizando el buffer de fosfato tratado con hielo seco para la extracción. Dentro de las ficobiliproteínas, fue la ficocianina la que se encontró en mayor proporción (FC = 77,74±0,767 mg L-1), seguido por la aloficocianina y ficoeritrina. Se concluye que la biomasa de Arthrospira maxima presenta potencial biotecnológico por sus altos contenidos de pigmentos.

Carbon dioxide capture strategies from flue gas using microalgae: a review

Global warming and pollution are the twin crises experienced globally. Biological offset of these crises are gaining importance because of its zero waste production and the ability of the organisms to thrive under extreme or polluted condition. In this context, this review highlights the recent developments in carbon dioxide (CO2) capture from flue gas using microalgae and finding the best microalgal remediation strategy through contrast and comparison of different strategies. Different flue gas microalgal remediation strategies discussed are as follows: (i) Flue gas to CO2 gas segregation using adsorbents for microalgal mitigation, (ii) CO2 separation from flue gas using absorbents and later regeneration for microalgal mitigation, (iii) Flue gas to liquid conversion for direct microalgal mitigation, and (iv) direct flue gas mitigation using microalgae. This work also studies the economic feasibility of microalgal production. The study discloses that the direct convening of flue gas with high carbon dioxide content, into microalgal system is cost-effective.

Strategies to enhance the production of photosynthetic pigments and lipids in chlorophycae species

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Microalgae are source of valuable compounds as lipids, proteins, carbohydrates, pigments among others.

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Culture stress conditions increase biomass and high values compounds in microalgae.

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Nitrogen and salt stress increase lipids in microalgae.

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Two stages culture and electromagnetic fields enhancing microalgae biomass and pigments content.

Microalgae are a major natural source for a vast array of valuable compounds as lipids, proteins, carbohydrates, pigments among others. Despite many applications, only a few species of microalgae are cultured commercially because of poorly developed of cultivation process. Nowadays some strategies of culture have been used for enhancing biomass and value compounds yield. The most strategies applied to microalgae are classified into two groups: nutrimental and physical. The nutrimental are considered as change in media composition as nitrogen and phosphorous limitation and changes in carbon source, while physical are described as manipulation in operational conditions and external factors such as application of high-light intensities, medium salinity and electromagnetic fields. The exposition to electromagnetic field is a promising technique that can improve the pigments and biomass yield in microalgae culture. Therefore, is important to describe the advantages and applications of the overall process. The aim of this review was to describe the main culture strategies used to improve the photosynthetic and lipids content in chlorophyceae species.

Bicarbonate-based Integrated Carbon Capture and Algae Production System with alkalihalophilic cyanobacterium

An extremely alkalihalophilic cyanobacteria Euhalothece ZM001 was tested in the Bicarbonate-based Integrated Carbon Capture and Algae Production System (BICCAPS), which utilize bicarbonate as carbon source for algae culture and use the regenerated carbonate to absorb CO2. Culture conditions including temperature, inoculation rate, medium composition, pH, and light intensity were investigated. A final biomass concentration of 4.79 g/L was reached in tissue flask culture with 1.0 M NaHCO3/Na2CO3. The biomass productivity of 1.21 g/L/day was achieved under optimal conditions. When pH increased from 9.55 to 10.51, 0.256 M of inorganic carbon was consumed during the culture process. This indicated sufficient carbon can be supplied as bicarbonate to the culture. This study proved that a high biomass production rate can be achieved in a BICCAPS. This strategy can also lead to new design of photobioreactors that provides an alternative supply of CO2 to sparging.