Microalgae Bioactive Carbohydrates as a Novel Sustainable and Eco-Friendly Source of Prebiotics: Emerging Health Functionality and Recent Technologies for Extraction and Detection

Ultrasound-driven facile fabrication of Pd doped SnO2 hierarchical superstructures: Structural, growth mechanism, dermatoglyphics, and anti-cancer activity

This research introduces a novel method that leverages Spirulina extract (S.E) as a bio-surfactant in the ultrasound-assisted synthesis (UAS) of Pd3+ (0.25-10 mol%) doped tin oxide (SnO2) self-assembled superstructures. Nanotechnology has witnessed significant advancements in recent years, driven by the exploration of novel synthesis methods and the development of advanced nanomaterials tailored for specific applications. Metal oxide nanoparticles, particularly SnO2, have garnered considerable attention due to their versatile properties and potential applications in various fields, including gas sensing, catalysis, and biomedical engineering. The study explores how varying influential parameters like S.E concentration, sonication time, pH, and sonication power can influence the resulting superstructures' morphology, size, and shape. A theoretical model for forming different hierarchical superstructures (HS) is proposed. X-ray diffraction (XRD) analysis confirms the crystalline tetragonal rutile phase of the SnO2:Pd HS. Raman spectroscopy reveals a red shift in the A1g mode, indicating phonon confinement due to various defects in the SnO2 structure. Further characterization using transmission electron microscopy (TEM), scanning electron microscopy (SEM), and X-ray photoelectron spectroscopy (XPS) provides insights into particle size, surface morphology, elemental composition, and binding energy. The study also demonstrates the application of optimized SnO2:3Pd HS in developing latent fingerprints (LFPs) on different surfaces using a simple powder dusting (PD) method, with the fingerprints (FPs) visualized under normal light. A mathematical model developed in Python-based software is used to analyze various features of the developed FPs, including pore properties such as number, position, inter-spacing, area, and shape. Additionally, an in vitro MTT assay shows concentration-dependent anticancer activity of SnO2:3Pd nanoparticles (NPs) on MCF7 cell lines, highlighting their potential as a promising cancer treatment option. Overall, the study suggests that the optimized HS can serve as multifunctional platforms for biomedical and dermatoglyphics applications, demonstrating the versatility and potential of the synthesized materials.

Reaction of Pyrrolobenzothiazines with Schiff Bases and Carbodiimides: Approach to Angular 6/5/5/5-Tetracyclic Spiroheterocycles

1H-Pyrrole-2,3-diones, fused at [e]-side with a heterocycle, are suitable platforms for the synthesis of various angular polycyclic alkaloid-like spiroheterocycles. Recently discovered sulfur-containing [e]-fused 1H-pyrrole-2,3-diones (aroylpyrrolobenzothiazinetriones) tend to exhibit unusual reactivity. Based on these peculiar representatives of [e]-fused 1H-pyrrole-2,3-diones, we have developed an approach to an unprecedented 6/5/5/5-tetracyclic alkaloid-like spiroheterocyclic system of benzo[d]pyrrolo[3',4':2,3]pyrrolo[2,1-b]thiazole via their reaction with Schiff bases and carbodiimides. The experimental results have been supplemented with DFT computational studies. The synthesized alkaloid-like 6/5/5/5-tetracyclic compounds have been tested for their biotechnological potential as growth stimulants in the green algae Chlorella vulgaris.

Effect of high-dose Spirulina supplementation on hospitalized adults with COVID-19: a randomized controlled trial

Objective

Spirulina (arthrospira platensis) is a cyanobacterium proven to have anti-inflammatory, antiviral, and antioxidant effects. However, the effect of high-dose Spirulina supplementation on hospitalized adults with COVID-19 is currently unclear. This study aimed to evaluate the efficacy and safety of high-dose Spirulina platensis for SARS-CoV-2 infection.

Study Design

We conducted a randomized, controlled, open-label trial involving 189 patients with COVID-19 who were randomly assigned in a 1:1 ratio to an experimental group that received 15.2g of Spirulina supplement plus standard treatment (44 non-intensive care unit (non-ICU) and 47 ICU), or to a control group that received standard treatment alone (46 non-ICU and 52 ICU). The study was conducted over six days. Immune mediators were monitored on days 1, 3, 5, and 7. The primary outcome of this study was mortality or hospital discharge within seven days, while the overall discharge or mortality was considered the secondary outcome.

Results

Within seven days, there were no deaths in the Spirulina group, while 15 deaths (15.3%) occurred in the control group. Moreover, within seven days, there was a greater number of patients discharged in the Spirulina group (97.7%) in non-ICU compared to the control group (39.1%) (HR, 6.52; 95% CI, 3.50 to 12.17). Overall mortality was higher in the control group (8.7% non-ICU, 28.8% ICU) compared to the Spirulina group (non-ICU HR, 0.13; 95% CI, 0.02 to 0.97; ICU, HR, 0.16; 95% CI, 0.05 to 0.48). In non-ICU, patients who received Spirulina showed a significant reduction in the levels of IL-6, TNF-α, IL-10, and IP-10 as intervention time increased. Furthermore, in ICU, patients who received Spirulina showed a significant decrease in the levels of MIP-1α and IL-6. IFN-γ levels were significantly higher in the intervention group in both ICU and non-ICU subgroups as intervention time increased. No side effects related to Spirulina supplements were observed during the trial.

Conclusion

High-dose Spirulina supplements coupled with the standard treatment of COVID-19 may improve recovery and remarkably reduce mortality in hospitalized patients with COVID-19.

Clinical Trial Registration

https://irct.ir/trial/54375, Iranian Registry of Clinical Trials number (IRCT20210216050373N1).

Spectral insights: Navigating the frontiers of biomedical and microbiological exploration with Raman spectroscopy

Raman spectroscopy (RS), a powerful analytical technique, has gained increasing recognition and utility in the fields of biomedical and biological research. Raman spectroscopic analyses find extensive application in the field of medicine and are employed for intricate research endeavors and diagnostic purposes. Consequently, it enjoys broad utilization within the realm of biological research, facilitating the identification of cellular classifications, metabolite profiling within the cellular milieu, and the assessment of pigment constituents within microalgae. This article also explores the multifaceted role of RS in these domains, highlighting its distinct advantages, acknowledging its limitations, and proposing strategies for enhancement.

Doxorubicin-Loaded Microalgal Delivery System for Combined Chemotherapy and Enhanced Photodynamic Therapy of Osteosarcoma

Osteosarcoma (OS) is considered the most frequent type of primary malignant bone tumor. Currently, radiotherapy, photodynamic (PDT), and other therapies for osteosarcoma are limited by tumor hypoxia and single efficacy and serve side-effects. Herein, we reported a microalgal drug delivery system (SpiD), doxorubicin (DOX)-loaded Spirulina platensis (Spi) for OS therapy. The specific surface of Spirulina platensis allowed for effective loading of DOX via surface channels and electrostatic interactions. Under 650 nm laser irradiation, SpiD enabled high oxygen production by photosynthesis and enhanced reactive oxygen species (ROS) generation via chlorophyll-assisted photosensitization, synergistically killing tumor cells with the released DOX. Combined chemotherapy and enhanced PDT mediated by SpiD exerted synergic antitumor effects and resulted in potent therapeutic efficacy in orthotopic osteosarcoma mice. Furthermore, SpiD could reduce the side-effects of chemotherapy, showing excellent blood and tissue safety. Taken together, this microalgal drug delivery system provided a natural, efficient, safe, and inexpensive strategy for OS treatment.

Microalgae polysaccharides exert antioxidant and anti-inflammatory protective effects on human intestinal epithelial cells in vitro and dextran sodium sulfate-induced mouse colitis in vivo

Microalgae polysaccharides (MAPS) have emerged as novel prebiotics, but their direct effects on intestinal epithelial barrier are largely unknown. Here, MAPS isolated from Chlorella pyrenoidosa, Spirulina platensis, and Synechococcus sp. PCC 7002 were characterized as mainly branched heteropolysaccharides, and were bioavailable to Caco-2 cells based on fluorescein isothiocyanate labeling and flow cytometry analysis. These MAPS were equally effective to scavenge hydroxyl and superoxide radicals in vitro and to attenuate the H2O2-, dextran sodium sulfate-, tumor necrosis factor α-, and interleukin 1β-induced burst of intracellular reactive oxygen species and mitochondrial superoxide radicals, interleukin-8 production, cyclooxygenase-2 and inducible nitric oxide synthase expression, and/or tight junction disruption in polarized Caco-2 cells. MAPS and a positive drug Mesalazine were intragastrically administered to C57BL/6 mice daily for 7 d during and after 4-d dextran sodium sulfate exposure. Clinical signs and colon histopathology revealed equivalent anti-colitis efficacies of MAPS and Mesalazine, and based on biochemical analysis of colonic tight junction proteins, goblet cells, mucin 2 and trefoil factor 3 transcription, and colonic and peripheral pro-inflammatory cytokines, MAPS alleviated dextran sodium sulfate-induced intestinal epithelial barrier dysfunction, and their activities were even superior than Mesalazine. Overall, MAPS confer direct antioxidant and anti-inflammatory protection to intestinal epithelial barrier function.

Advances in oligosaccharides production from brown seaweeds: extraction, characterization, antimetabolic syndrome, and other potential applications

Brown seaweeds are a promising source of bioactive substances, particularly oligosaccharides. This group has recently gained considerable attention due to its diverse cell wall composition, structure, and wide-spectrum bioactivities. This review article provides a comprehensive update on advances in oligosaccharides (OSs) production from brown seaweeds and their potential health applications. It focuses on advances in feedstock pretreatment, extraction, characterization, and purification prior to OS use for potential health applications. Brown seaweed oligosaccharides (BSOSs) are extracted using various methods. Among these, enzymatic hydrolysis is the most preferred, with high specificity, mild reaction conditions, and low energy consumption. However, the enzyme selection and hydrolysis conditions need to be optimized for desirable yield and oligosaccharides composition. Characterization of oligosaccharides is essential to determine their structure and properties related to bioactivities and to predict their most suitable application. This is well covered in this review. Analytical techniques such as high-performance liquid chromatography (HPLC), gas chromatography (GC), and nuclear magnetic resonance (NMR) spectroscopy are commonly applied to analyze oligosaccharides. BSOSs exhibit a range of biological properties, mainly antimicrobial, anti-inflammatory, and prebiotic properties among others. Importantly, BSOSs have been linked to possible health advantages, including metabolic syndrome management. Metabolic syndrome is a cluster of conditions, such as obesity, hypertension, and dyslipidemia, which increase the risk of cardiovascular disease and type 2 diabetes. Furthermore, oligosaccharides have potential applications in the food and pharmaceutical industries. Future research should focus on improving industrial-scale oligosaccharide extraction and purification, as well as researching their potential utility in the treatment of various health disorders.[Figure: see text].

Applications of Microalgae in Foods, Pharma and Feeds and Their Use as Fertilizers and Biostimulants: Legislation and Regulatory Aspects for Consideration

Microalgae are a rich resource of lipids, proteins, carbohydrates and pigments with nutritional and health benefits. They increasingly find use as ingredients in functional foods and feeds as well as in cosmetics and agricultural products including biostimulants. One of their distinct advantages is their ability to grow on wastewaters and other waste streams, and they are considered an environmentally friendly and cheap method to recover nutrients and remove pollutants from the environment. However, there are limits concerning their applications if grown on certain waste streams. Within, we collate an overview of existing algal applications and current market scenarios for microalgal products as foods and feeds along with relevant legislative requirements concerning their use in Europe and the United States. Microalgal compounds of interest and their extraction and processing methodologies are summarized, and the benefits and caveats of microalgae cultivated in various waste streams and their applications are discussed.

Identification and Characterization of a Novel Microalgal Strain from the Antofagasta Coast Tetraselmis marina AC16-MESO (Chlorophyta) for Biotechnological Applications

The wide rocky coastline of the Antofagasta hosts an intertidal ecosystem in which the species that inhabit it are routinely exposed to a wide range of physical and chemical conditions and have therefore evolved to tolerate extremes. In the search for new species of potential biotechnological interest with adaptations to a wide range of environmental conditions, the isolation and characterization of microalgae from these ecosystems is of great interest. Here, a new microalgal strain, Tetraselmis marina AC16-MESO, is described, which was isolated from a biofilm collected on the intertidal rocks of the Antofagasta coast (23°36'57.2″ S, 70°23'33.8″ W). In addition to the morphological characterization, 18S and ITS sequence as well as ITS-2 secondary structure analysis revealed an identity of 99.76% and 100% with the species Tetraselmis marina, respectively. The analyses of the culture characteristics and biochemical content showed similarities with other strains that are frequently used in aquaculture, such as the species Tetraselmis suecica. In addition, it is tolerant of a wide range of salinities, thus allowing its culture in water of varying quality. On the other hand, added to these characteristics, the results of the improvement of the lipid content in stressful situations of salinity observed in this study, together with other antecedents such as the potential in bioremediation already published for this strain by the same research group, present a clear example of its biotechnological plasticity. It is noteworthy that this strain, due to its characteristics, allows easy collection of its biomass by decantation and, therefore, a more cost-efficient harvesting than for other microalgal strains. Therefore, this new strain of Tetraselmis marina, first report of this species in Chile, and its morphologically, molecularly and biochemically description, presents promising characteristics for its use in biotechnology and as feed for aquaculture.

Growth Behavior, Biomass Composition and Fatty Acid Methyl Esters (FAMEs) Production Potential of Chlamydomonas reinhardtii, and Chlorella vulgaris Cultures

The production of biomolecules by microalgae has a wide range of applications in the development of various materials and products, such as biodiesel, food supplements, and cosmetics. Microalgae biomass can be produced using waste and in a smaller space than other types of crops (e.g., soja, corn), which shows microalgae's great potential as a source of biomass. Among the produced biomolecules of greatest interest are carbohydrates, proteins, lipids, and fatty acids. In this study, the production of these biomolecules was determined in two strains of microalgae (Chlamydomonas reinhardtii and Chlorella vulgaris) when exposed to different concentrations of nitrogen, phosphorus, and sulfur. Results show a significant microalgal growth (3.69 g L-1) and carbohydrates (163 mg g-1) increase in C. reinhardtii under low nitrogen concentration. Also, higher lipids content was produced under low sulfur concentration (246 mg g-1). It was observed that sulfur variation could affect in a negative way proteins production in C. reinhardtii culture. In the case of C. vulgaris, a higher biomass production was obtained in the standard culture medium (1.37 g L-1), and under a low-phosphorus condition, C. vulgaris produced a higher lipids concentration (248 mg g-1). It was observed that a low concentration of nitrogen had a better effect on the accumulation of fatty acid methyl esters (FAMEs) (C16-C18) in both microalgae. These results lead us to visualize the effects that the variation in macronutrients can have on the growth of microalgae and their possible utility for the production of microalgae-based subproducts.

The Recent Development of Acoustic Sensors as Effective Chemical Detecting Tools for Biological Cells and Their Bioactivities

One of the most significant developed technologies is the use of acoustic waves to determine the chemical structures of biological tissues and their bioactivities. In addition, the use of new acoustic techniques for in vivo visualizing and imaging of animal and plant cellular chemical compositions could significantly help pave the way toward advanced analytical technologies. For instance, acoustic wave sensors (AWSs) based on quartz crystal microbalance (QCM) were used to identify the aromas of fermenting tea such as linalool, geraniol, and trans-2-hexenal. Therefore, this review focuses on the use of advanced acoustic technologies for tracking the composition changes in plant and animal tissues. In addition, a few key configurations of the AWS sensors and their different wave pattern applications in biomedical and microfluidic media progress are discussed.

Nanoparticles from Microalgae and Their Biomedical Applications

Over the years, microalgae have been a source of useful compounds mainly used as food and dietary supplements. Recently, microalgae have been used as a source of metabolites that can participate in the synthesis of several nanoparticles through inexpensive and environmentally friendly routes alternative to chemical synthesis. Notably, the occurrence of global health threats focused attention on the microalgae application in the medicinal field. In this review, we report the influence of secondary metabolites from marine and freshwater microalgae and cyanobacteria on the synthesis of nanoparticles that were applied as therapeutics. In addition, the use of isolated compounds on the surface of nanoparticles to combat diseases has also been addressed. Although studies have proven the beneficial effect of high-value bioproducts on microalgae and their potential in medicine, there is still room for understanding their exact role in the human body and translating lab-based research into clinical trials.

Evaluation of carbon dioxide elevation on phenolic compounds and antioxidant activity of red onion (Allium cepa L.) during postharvest storage

Carbon dioxide (CO₂) is considered one of the eco-related key factors that negatively affect global climatic change. Also, CO₂ can play an important role in the postharvest quality of the agri-products. In this study, the impact of CO₂ on the quality of postharvest onions that were stored at 23 °C for 8 weeks was investigated. The weight loss, phenolic, flavonoid, flavanol, anthocyanin, antioxidant activity, and soluble sugar were analyzed during the study period. The results showed that 20% CO₂ treatment was significantly (P > 0.05) more effective than 15% CO₂ and control in inhibiting weight loss. Additionally, 20% CO₂ treatment significantly retained higher antioxidant enzyme activities such as CAT, APX, and SOD than 15% CO₂ and control. During storage, 20% CO₂ treatment significantly (P < 0.05) improved glucose, fructose, and sucrose levels by more than 15% CO₂ exposure and control groups. Besides the chlorogenic acid, kaempferol and quercetin were significantly (P < 0.05) higher in the 20% CO₂ than in the 15% CO₂ after 2 weeks of storage. In conclusion, this study's novelty comes from the broad prospects of using CO₂ for maximizing the stored onion phytochemical functionality that is usually affected by the room temperature long storage. This will help in the onion shelf-life extension by considering the quality-related attributes.

Polysaccharides from Spirulina platensis: Extraction methods, structural features and bioactivities diversity

Spirulina platensis, a well-known blue-green microalga cultivated and consumed in China and United States, is traditionally used as a food supplement and medical ingredient. Increasing evidence has confirmed that the Spirulina platensis polysaccharides (SPPs) are vital and representative pharmacologically active biomacromolecules and exhibit multiple health-promoting activities both in vivo and in vitro, such as those of anti-cancer, anti-oxidant, immunomodulatory, hypolipidemic and hypoglycemic, anti-thrombotic, anti-viral, regulation of the gut microbiota properties and other biological activity. The purpose of this review aims to comprehensively and systematically outline the extraction and purification methods, structural features, biological activities, underlying mechanisms, and toxicities of SPPs to support their potential utilization value in pharmaceuticals fields and functional foods. The structural and activities relationship of SPPs is also discussed. Besides, new valuable insights for future research with SPPs have also been proposed in the important areas of structural characterization and pharmacological activities.

The development of live microorganism-based oxygen shuttles for enhanced hypoxic tumor therapy

Hypoxia is a prominent feature of malignant tumors and contributes to tumor proliferation, metastasis, and drug resistance in various solid tumors. Therefore, improving tumor oxygenation is crucial for curing tumors. To date, multiple strategies, including oxygen delivering and producing materials, have been designed to increase the oxygen concentration in hypoxic tumors. However, the unsustainable supply of oxygen is still the main obstacle, resulting in a suboptimal outcome in treating oxygen-deprived tumors. Thus, a sufficient oxygen supply is highly desirable in the treatment of hypoxic tumors. Photosynthesis, as the main source of oxygen in nature through the conversion of light energy into chemical energy and oxygen, has been widely studied in scientific research. Moreover, photosynthetic microorganisms have been increasingly applied in cancer therapy by increasing oxygenation, which improves the therapeutic effect of oxygen-consuming tumor therapeutic tools such as radiotherapy and photodynamic therapy. In this review, we summarize recent advances in the design and manufacture of live bacteria as oxygen shuttles for a new generation of hypoxic tumor treatment strategies. Finally, current challenges and future directions are also discussed for successfully addressing hypoxic tumor issues.

Update on the application of magnetic fields to microalgal cultures

Several studies have shown that any magnetic field (MF) applied to microalgae modifies its cultivation conditions and may favor biomolecule production since it interacts with the microorganisms and affect their growth. As a result, there are changes in concentrations and compositions of biomass and biomolecules. This review aims at updating MF applications to microalga cultures that were reported by studies conducted in the last 5 years. It shows the main studies that reached positive results of carbohydrate, lipid, protein and pigment production. Effects of MFs may be positive, negative or null, depending on some factors, such as intensity, exposure time, physiological state of cells and application devices. Therefore, this review details cultivation conditions used for reaching high concentration of biomolecules, explains the action of MFs on microalgae and describes their applicability to the biorefinery concept.

Microalgae-Based PUFAs for Food and Feed: Current Applications, Future Possibilities, and Constraints

Microalgae are currently considered an attractive source of highly valuable compounds for human and animal consumption, including polyunsaturated fatty acids (PUFAs). Several microalgae-derived compounds, such as ω-3 fatty acids, pigments, and whole dried biomasses are available on the market and are mainly produced by culturing microalgae in open ponds, which can be achieved with low setup and maintenance costs with respect to enclosed systems. However, open tanks are more susceptible to bacterial and other environmental contamination, do not guarantee a high reproducibility of algal biochemical profiles and productivities, and constrain massive cultivation to a limited number of species. Genetic engineering techniques have substantially improved over the last decade, and several model microalgae have been successfully modified to promote the accumulation of specific value-added compounds. However, transgenic strains should be cultured in closed photobioreactors (PBRs) to minimize risks of contamination of aquatic environments with allochthonous species; in addition, faster growth rates and higher yields of compounds of interest can be achieved in PBRs compared to open ponds. In this review, we present information collected about the major microalgae-derived commodities (with a special focus on PUFAs) produced at industrial scale, as well genetically-engineered microalgae to increase PUFA production. We also critically analyzed the main bottlenecks that make large-scale production of algal commodities difficult, as well as possible solutions to overcome the main problems and render the processes economically and environmentally safe.

Microalgae Polysaccharides: An Alternative Source for Food Production and Sustainable Agriculture

Carbohydrates or polysaccharides are the main products derived from photosynthesis and carbon fixation in the Calvin cycle. Compared to other sources, polysaccharides derived from microalgae are safe, biocompatible, biodegradable, stable, and versatile. These polymeric macromolecules present complex biochemical structures according to each microalgal species. In addition, they exhibit emulsifying properties and biological characteristics that include antioxidant, anti-inflammatory, antitumor, and antimicrobial activities. Some microalgal species have a naturally high concentration of carbohydrates. Other species can adapt their metabolism to produce more sugars from changes in temperature and light, carbon source, macro and micronutrient limitations (mainly nitrogen), and saline stress. In addition to growing in adverse conditions, microalgae can use industrial effluents as an alternative source of nutrients. Microalgal polysaccharides are predominantly composed of pentose and hexose monosaccharide subunits with many glycosidic bonds. Microalgae polysaccharides can be structural constituents of the cell wall, energy stores, or protective polysaccharides and cell interaction. The industrial use of microalgae polysaccharides is on the rise. These microorganisms present rheological and biological properties, making them a promising candidate for application in the food industry and agriculture. Thus, microalgae polysaccharides are promising sustainable alternatives for potential applications in several sectors, and the choice of producing microalgal species depends on the required functional activity. In this context, this review article aims to provide an overview of microalgae technology for polysaccharide production, emphasizing its potential in the food, animal feed, and agriculture sector.

Influence of Process Operation on the Production of Exopolysaccharides in Arthrospira platensis and Chlamydomonas asymmetrica

Extracellular polysaccharides, or exopolysaccharides are high–molecular weight sugar-based polymers expressed and secreted by many microorganisms. As host organisms, the functions of exopolysaccharides are diverse, ranging from physical protection via biofilm formation, adhesion, and water retention to biological functions that are not entirely understood such as viral attachment inhibition. Industrial applications of exopolysaccharides can be found in food texture modification; for example, utilizing the hydrocolloidal properties of exopolysaccharides for thickening and gelling purposes to improve food quality and texture. Over the last decade, biologically active exopolysaccharides produced by microalgae have received attention for their potential as antiviral, antibacterial and antioxidative compounds and in the applications. However, relatively low yield and productivity are the limiting factors for full-scale industrial application. In this study, the well-known prokaryotic phototrophic microorganism Arthrospira platensis and the comparatively unknown eukaryotic unicellular green alga Chlamydomonas asymmetrica were used to evaluate the influence of different process parameters on exopolysaccharides formation and productivity. In addition to the essential control variables (light and temperature), the influence of operational techniques (batch and turbidostat) were also investigated. Although the two studied algae are differently affected by above parameters. The light intensity was the most influential parameter observed in the study, leading to differences in exopolysaccharides concentrations by a factor of 10, with the highest measured concentration for A. platensis of cEPS = 0.138 g L−1 at 180 μmol m−2 s−1 and for C. asymmetrica of cEPS = 1.2 g L−1 at 1,429 μmol m−2 s−1. In continuous systems, the achieved exopolysaccharides concentrations were low compared to batch process, however, slightly higher productivities were reached. Regardless of all screened process parameters, C. asymmetrica is the better organism in terms of exopolysaccharides concentrations and productivity.