Microalgae Based Natural Dye Chemical Obtaining
1. Introduction
Paint technologies have been used for both aesthetic and functional purposes throughout human history, and today they have become a sector that includes multidisciplinary scientific and industrial application areas, reaching a market volume of billions of dollars on a global scale. Paints are of critical importance not only for the purpose of coloring surfaces, but also for protecting surfaces, providing resistance against environmental effects and increasing chemical-physical stability [1]. The chemical compositions of these materials used in many different sectors such as industry, automotive, construction, furniture, electronics, textile, defense and food determine their performance properties as well as their environmental and toxicological profiles. For this reason, multi-faceted evaluation of the structural components of paint chemicals and the potential effects of these components on the environment and human health has become both a scientific and sectoral necessity today [2].
Paints are basically composed of various chemical components such as pigments (coloring agents), binders (film-forming polymers), solvents (fluidizers), additives (driers, stabilizers, flow regulators, etc.) and fillers. These components directly affect the performance parameters of the paint such as physical and chemical durability, coating quality, drying time and resistance to environmental conditions. However, a significant portion of these chemical contents pose serious risks to human health and the environment. Pigments containing volatile organic compounds (VOCs), formaldehyde, isocyanates, phthalates, heavy metals such as lead, chromate, cadmium and arsenic are of high toxicological importance in environments with intense environmental exposure [3].
VOCs are released into the atmosphere during application and drying stages; when inhaled, they can cause serious health problems in vital systems such as the nervous system, respiratory system and liver. These compounds, which accumulate in high concentrations especially in closed areas, can cause headaches, nausea, eye-nose-throat irritation, neurotoxicity and in some cases, carcinogenic effects. Scientific studies have clearly shown that pigments containing heavy metals pose long-term health threats due to bioaccumulation effect when in contact with skin or inhaled; they have kidney damage, bone deformations, weakened immune system and negative effects on fertility. In addition, it has been reported that such chemicals have disruptive effects on the endocrine system and can cause developmental problems especially in children by affecting hormonal balance [4].
When evaluated from an environmental perspective, paint wastes contain pollutants released into the air, water and soil environment during both production and application stages. Uncontrolled disposal of paint residues leads to the accumulation of toxic substances in underground and surface waters; this disrupts the biological processes of aquatic creatures and threatens the ecosystem balance. In addition, these pollutants negatively affect human health indirectly by entering the food chain. High-performance paints, especially those used in the textile and automotive industries, are considered among the substances that create permanent pollution in the environment together with microplastics [5].
In the face of all these risks, paint manufacturers and implementing companies are under increasing pressure to develop sustainability-oriented strategies. Regulatory frameworks such as the European Green Deal and REACH limit the use of toxic chemicals and direct manufacturers to environmentally friendly alternatives. In this context, solutions such as water-based paints, low VOC formulations, biodegradable binders, pigments of natural origin (e.g. plant or mineral origin) and photocatalytic active coatings come to the fore. At the same time, high-performance, low-toxicity paint systems developed thanks to nanotechnological approaches are also considered as a rising trend in the sector [6].
For companies, turning to paint technologies that are sensitive to the environment and human health is not only an ethical responsibility, but also an economic and strategic necessity. Brands that develop environmentally friendly products, reduce their ecological footprint and minimize toxic effects both comply with legal regulations and increase their potential to be the choice of conscious consumers. Especially for export-oriented companies, compliance with international certifications becomes an important advantage in market competition [7].
Production of Microalgae Based Natural Dye Chemicals
In line with the increasing global trends towards the development of environmentally friendly and sustainable products in recent years, microalgae have attracted attention as an innovative and environmentally compatible source in the field of natural pigment and dye production. Microalgae, which are photosynthetic microorganisms, are increasingly preferred in bioindustrial processes due to their high biomass production capacity, fast growth rates, ability to be cultivated in different environments and potential to produce biologically active compounds. It is stated that microalgae-derived pigments constitute a sustainable alternative to traditional synthetic dyes because they do not contain toxic solvents and heavy metals and are biodegradable [8].
The natural pigments contained in microalgae are collected in various classes such as chlorophylls, carotenoids (β-carotene, lutein, astaxanthin), phycobilins (phycocyanin, phycoerythrin), and these pigments offer versatile usage advantages with both their coloring properties and antioxidant, antimicrobial and UV protective effects. For example; phycocyanin obtained from Spirulina platensis is a natural pigment with a blue color and can be used in the cosmetics, food and textile sectors. While Haematococcus pluvialis stands out with its astaxanthin production in red tones; Chlorella vulgaris and Dunaliella salina contribute to the search for natural colors with their chlorophyll and β-carotene production in green and orange tones [9].
The fact that microalgae-derived dyes are highly biodegradable, do not harm human health and have a low carbon footprint in terms of environmental impact, especially in the textile and packaging sector, supports the applicability of these technologies on an industrial scale. In addition, the fact that not only pigments but also valuable by-products such as proteins, lipids and carbohydrates are obtained from microalgae biomass makes these systems compatible with the principles of circular economy [10].
In this context, microalgae-based natural dye production offers an important window of opportunity for the dye industry in terms of both sustainability and innovation. Especially for synthetic dye producers, microalgae-based solutions have become the focus of R&D investments in order to develop alternatives that minimize toxicology risks, comply with regulations, and appeal to ecological markets. Collaborations in this field in the industry are increasing with the establishment of high-capacity cultivation systems, process optimizations, and the development of advanced technological formulations that will increase the stability of natural pigments [11].
In this study, it is aimed to evaluate the natural green pigment obtained by extraction of chlorophyll pigment from Chlorella vulgaris microalgae as a dye raw material. This approach, especially aimed at developing environmentally friendly, biodegradable and non-toxic dyes, aims to contribute to the dissemination of sustainable production technologies. The study reveals the potential of microalgae-based dyes as an alternative to traditional synthetic dyes and contributes to biotechnological pigment production processes.
2. Material and Methods
2.1. Selection and Cultivation of Microalgae Species
microalgae to be used for dye chemical production can be selected according to the desired pigment type and the targeted application area. For example; Spirulina platensis → Phycocyanin (blue pigment), Haematococcus pluvialis → Astaxanthin (red pigment) and Chlorella vulgaris and Dunaliella salina → Chlorophyll and β- carotene (green/orange pigments). Microalgae are cultured in open systems (e.g. raceway ponds) or in closed photobioreactors under controlled conditions. Parameters such as nutrient medium, pH, temperature, light intensity and CO₂ gas level are adjusted to optimize pigment production. In particular, secondary pigments such as carotenoids and phycobilin Synthesis of metabolites may increase due to light stress and nitrogen limitation.
2.2. Harvesting and Drying of Biomass
Microalgae cultures are collected as biomass during the harvesting phase by methods such as centrifugation , filtration or flocculation . The wet biomass obtained is dried at low temperature (e.g. freeze drying-lyophilization) to maintain pigment stability. This process prevents oxidation of the pigment and extends its shelf life.
2.3. Pigment Extraction
Extraction process is applied to obtain pigments from dried biomass . Water or buffer solutions are used for hydrophilic pigments such as phycocyanin and chlorophyll. Solvents such as ethanol, acetate, hexane are used for lipophilic pigments such as carotenoids and astaxanthin. Green solvents (e.g. ethanol, supercritical CO₂) are preferred within the framework of the environmentally friendly approach. Ultrasonic homogenization, soxhlet extraction , microwave assisted extraction or enzymatic cell destruction techniques can be used. The extracted pigments are brought to concentrated pigment form by evaporating the solvent.
2.4. Paint Formulation
extract obtained is converted into paint chemicals by combining it with suitable carrier agents according to the application area. At this stage: Water -based dispersions, Biopolymer carriers (e.g. PVA, chitosan , cellulose derivatives), Stabilizers and emulsifiers (e.g. glycerol , lecithin ) and Natural resins and binders are used. The formulation is optimized in terms of properties such as viscosity, pH , color intensity, heat and UV stability. The product can be prepared in liquid form or as a spray/sol-gel formulation .
2.5. Application and Characterization
The obtained dye chemical is applied to the target surface (e.g. textile fabric, paper, bioplastic, wood, food packaging) and its performance is tested. The dye is characterized by parameters such as color intensity , light and heat resistance , friction resistance , toxicological safety tests (e.g. Ames test, cytotoxicity test). At the end of this process, the obtained microalgae based paint chemical, is an environmentally friendly, biodegradable, non- toxic and multi-purpose usable product. It also reduces industrial waste production, lowers carbon footprint and contributes to the principle of sustainability.
3. Conclusion and Discussion
In this study, selected microalgae species (e.g. Spirulina platensis , Haematococcus pluvialis and Chlorella vulgaris ) different extraction methods were used to successfully isolate natural pigments and convert them into environmentally friendly paint chemical formulations . The pigments obtained have stood out as an alternative to industrial paint chemicals with their high color density, biodegradable structure and non -toxicity.
Applied characterization tests, it was observed that microalgae- derived dye formulations were resistant to UV rays, and their heat and light stability were comparable to traditional synthetic dyes. It was determined that especially phycocyanin , β- carotene and astaxanthin pigments gave promising results in terms of color permanence. It was observed that pigment stability was positively correlated with the type of carrier matrix (e.g. PVA, chitosan) and natural antioxidants added to the formulation .
The study also evaluated the effects of extraction method and process parameters on pigment yield. In particular, in processes performed using ultrasonic -assisted extraction and ethanol -based solvents, up to 20% higher pigment yield was obtained compared to conventional methods. This finding indicates the environmentally friendly and economically sustainable scalability of the process.
Microalgae Based paint products have not shown any cytotoxic or mutagenic effects in toxicological analyses, making them a safe alternative for both industrial and consumer products. In this respect, the products are suitable even for sensitive areas of use such as food packaging, textile products, bioplastic surface coatings, cosmetic pigments and children's products.
In addition, the microalgae production process reduces environmental CO₂ through photosynthetic carbon fixation . The reduction of emissions and the ability to obtain value-added components such as proteins, lipids and polysaccharides as by-products make biodye technology quite attractive within the framework of the circular economy. Thus, microalgae -based dye systems should be considered as an economical, functional and sustainable solution not only for the environment and human health, but also for the industry.
integrate such biotechnological products into existing production lines. Cost/performance optimization can be achieved by reformulating existing paint lines or switching to natural- based solvents. In addition, microalgae can be used in the context of green certifications, carbon credit systems and eco-labeling programs. based paint products are expected to add value to brands.
4. References
[1] Soleymani, S. (2015). The effects of plant dyes, watercolours and acrylic dyes on the physical, chemical and biological stability of Japanese tissue paper used in paper conservation (Doctoral dissertation, University of Canberra).
[2] Pagnin, L., Guarnieri, N., Izzo, F.C., Goidanich, S., & Toniolo, L. (2023). Protecting Street Art from Outdoor Environmental Threats: What Are the Challenges?. Coatings , 13 (12), 2044.
[3] Tozlu, H. (2012). Investigation of Some Additives Used in the Production of Polymer Containing Materials (Doctoral dissertation).
[4] Guarnotta, V., Amodei, R., Frasca, F., Aversa, A., & Giordano, C. (2022). Impact of chemical endocrine disruptors and hormone modulators on the endocrine system. International journal of molecular sciences , 23 (10), 5710.
[5] Forero-López, AD, Colombo, CV, Loperena, AP, Morales-Pontet, NG, Ronda, AC, Lehr, IL, ... & Botté, SE (2024). Paint particle pollution in aquatic environments: Current advances and analytical challenges. Journal of Hazardous Materials , 135744.
[6] Hanus, M. J., & Harris, A. T. (2013). Nanotechnology innovations for the construction industry. Progress in materials science , 58 (7), 1056-1102.
[7] Esty, D.C., & Winston, A. (2009). Green to gold: How smart companies use environmental strategy to innovate, create value, and build competitive advantage . John Wiley & Sons.
[8] Silva, SC, Ferreira, IC, Dias, MM, & Barreiro, MF (2020). Microalgae-derived pigments: A 10-year bibliometric review and industry and market trend analysis. Molecules , 25 (15), 3406.
[9] Sandesh Kamath, B. (2007). Biotechnological production of microalgal carotenoids with reference to astaxanthin and evaluation of its biological activity (Doctoral dissertation, University of Mysore).
[10] Cheirsilp, B., Maneechote, W., Srinuanpan, S., & Angelidaki, I. (2023). Microalgae as tools for bio-circular-green economy: Zero-waste approaches for sustainable production and biorefineries of microalgal biomass. Bioresource Technology , 387 , 129620.
[11] Dubey, S.K., Dey, A., Singhvi, G., Pandey, M.M., Singh, V., & Kesharwani, P. (2022). Emerging trends of nanotechnology in advanced cosmetics. Colloids and surfaces B: Biointerfac es , 214 , 112440.
Erdi Buluş
Öğretim Görevlisi / Lecturer
İstanbul Arel Üniversitesi / Istanbul Arel University
ArelPOTKAM
