Tannery industrial effluent (TIE) contains high levels of organic matter, nitrogen, and dissolved solids, which can challenge the ability of conventional biological treatment to consistently achieve regulatory compliance. This study evaluated a two-stage cultivation system using Chlorella vulgaris (C. vulgaris) with centrifuged TIE at three C. vulgaris concentrations (CVG 10%, CVG 20%, and CVG 30%). The study evaluated pollutant removal, microalgal growth, molecular and morphological strain identification, and fatty acid methyl ester (FAME) characterization. The operational performance of the existing full-scale activated sludge (AS) system was also used as a practical benchmark to provide context for the laboratory-scale treatment. Among the tested conditions, CVG 30% exhibited the highest treatment performance, achieving removal efficiencies of 92.94±1.40% for BOD5, 91.60±0.16% for COD, 99.80±0.07% for ammonia, and 58.40±5.05% for TDS. Final BOD5, COD, and ammonia concentrations complied with regulatory discharge standards, whereas TDS remained above the permissible limit, indicating the need for additional polishing treatment. FAME analysis of the harvested biomass from the best-performing condition (CVG 30%) showed a fatty acid profile dominated by methyl linoleate (C18:2), methyl cis-11-eicosenoate (C20:1), and methyl palmitate (C16:0). Overall, two-stage C. vulgaris cultivation demonstrated potential for use as a complementary biological treatment approach for tannery wastewater, while FAME characterization provided insights into the fatty acid composition of biomass from the best-performing condition.

Precise spatiotemporal control of chemical gradients is crucial for studying microbial chemotaxis. However, traditional microfluidic platforms using poly(dimethylsiloxane) and soft lithography present a high barrier to entry due to their reliance on cleanrooms, specialized molds, and complex external pumping systems. To address these challenges, we introduce a rapid, cleanroom-free, 3D-printed microfluidic assay that simplifies the quantification of microbial chemotaxis and motility. Manufactured in under 4 h using high-resolution stereolithography 3D printing, the device maintains a standard 25 × 75 mm2 footprint for effortless microscope integration. Its monolithic, three-chamber design incorporates a central truncated-cone agar well that mechanically secures a hydrogel barrier, generating well-defined, diffusion-based transient chemical gradients without the need for external equipment. Physical characterization via visual flow tests with high-contrast dye confirmed robust leak prevention and unidirectional transient gradient formation within a quantified operational time window. As a biological proof-of-concept, the platform successfully quantified the concentration-dependent chemotactic response of Chlamydomonas reinhardtii to sodium bicarbonate, revealing peak sensitivity at 10−3M (p < 0.001) while capturing population heterogeneity. Additionally, parallel evaluations with the morphologically distinct Euglena gracilis demonstrated the platform’s architectural adaptability to diverse cell sizes and shapes. These evaluations confirmed the assay’s efficacy in isolating active chemotaxis from passive fluid drift and context-dependent motility. Ultimately, this accessible, rapid-prototyping platform provides a highly customizable tool for investigating complex microbial behavioral dynamics.

Integrating astaxanthin production by using Haematococcus lacustris with the LDP phycoremediation provides multiple benefits. However, as a highly sensitive organism, the cultivation needs to be regulated, such as selecting the most favorable media, regulating light intensity, adjusting LDP conentration, and evaluating the effect of NaCl on astaxanthin biosynthesis. In this study, we developed a new cultivation method, three-stage continuous cultivation system, by regulating the light intensity at each stage of microalgae growth. Based on the evaluation, the ideal medium was MES-volvox. The favorable light intensity for the adaptation phase was 600 lux, with the best LDP concentration of 3.75% and NaCl 1 g/L. The desirable light intensity in the three-stage cultivation system was 600 lux (days 0-6), 1,200 lux (days 6-16), and 3,500 lux (days 16-30). This system produced density, biomass, and astaxanthin content up to 91.54 × 104 cells/mL, 1 g/L, 0.83 g/L, respectively. Remarkably, the enrichment of NaCl did not reduce the density, carbohydrate, protein, or pigment content. Therefore, it may serve as a safe astaxanthin-enhancing stressor in the cultivation of this microalgae.

Massive palm oil production leads to the accumulation of liquid digestate of POME (LDP), which contains high levels of COD and other organic compounds. One potential alternative approach to treating this issue is through phycoremediation using Haematococcus lacustris, the highest producer of astaxanthin. Astaxanthin is a high-value keto-carotenoid pigment due to its notable antioxidant activity. However, cultivating this microalga is highly challenging, as determined by the stress applied. Therefore, in this study, we evaluated the effects of adding 1 g/L NaCl and high light intensities in H. lacustris cultivated in LDP-based media under continuous three stage cultivation system. Based on our study, low light intensity (3500 lux) produced higher biomass and carbon fixation rate than the other treatments (59.37 gCO₂/L/year). The treatment exposed to 10,000 lux yielded the highest cell density, carbohydrate content, chlorophyll-a, chlorophyll-b, total chlorophyll (90.17 ± 9.95 × 10⁴ cells/mL, 0.51 ± 0.03 g/L, 1.09 ± 0.14 mg/L, 0.48 ± 0.09 mg/L, and 1.57 ± 0.23 mg/L). Meanwhile, under 20,000 lux, it produced higher astaxanthin content than the other treatments (6.05 ± 0.68 mg/L, 6.72 ± 0.76 mg/g, and 0.67 ± 0.08%). The growth pattern was also consistent with the kinetics modelling using Logistic, Richards, and Gompertz models. Moreover, based on microbial quality analysis, the biomass complies with the standards with TPC values <5 × 10⁷ CFU/g and YMC <5 × 10⁵ CFU/g. Thus, the findings indicate that LDP-based cultivation of H. lacustris holds significant promise for further exploration to provide sufficient biomass for bioindustries applications integrated with wastewater remediation.

Euglena is one of the alternative natural resources for medicine, food, and energy, and it is important to develop its metabolic contents to fulfill human demands. Improvement of metabolic content in Euglena was conducted in several ways, such as by adding the phytohormone. Brassinolide is one of the phytohormones and is well-known for its ability to stimulate and protect the plant from stressful environments. The application of brassinolide is still lacking. In addition, previous studies have never applied this phytohormone to Euglena sp. cultures. This research aimed to analyze the effect of brassinolide on the growth, metabolic content and wax fermentation in Euglena sp. The growth rate was measured during cultivation, and the metabolic content was analyzed at the late exponential phase before entering the fermentation process. Gas Chromatography-Mass Spectrometry (GC-MS) was carried out to reveal the wax ester content after the fermentation process. The result showed that brassinolide significantly increased the growth rate and metabolic content at lower concentrations, while high concentration tends to inhibit the effect. The high metabolite content, including carbohydrate, lipid, protein, and paramylon, was 0.47 ± 0.02 g/L, 0.20 ± 0.01 g/L, 15.91 ± 1.21 × 10-3 g/L, and 145 ± 0.10 × 10-3 g/L, respectively. Interestingly, wax esters at lower brassinolide concentrations showed contrasting results compared to the control treatment. These findings provide information about the effect of brassinolide in Euglena sp., and advanced research is needed to reveal the mechanism of brassinolide in Euglena sp.

Euglena gracilis is a photosynthetic Euglenophyte capable of carbon dioxide fixation and lipid synthesis, offering a sustainable approach to renewable energy production. This study investigates the effects of mono- and multi-light spectra on the growth and fatty acid methyl ester (FAME) production of E. gracilis. The cultures were subjected to various light spectra, including red, blue, purple, red-blue, and white (control), to analyze their impact on growth rates, lipid accumulation, and FAME profiles. Growth metrics, including cell density, biomass, specific growth rate, and doubling time, were recorded, and FAME analysis was performed using GC-FID. Results indicated that purple light significantly enhanced growth, achieving the highest saturated fatty acid (SFA) content (31.7%), while red-blue light yielded the highest lipid concentration (0.680 ± 0.028 g L⁻¹). In contrast, blue light promoted the production of unsaturated fatty acids (UFA), with a composition of 74.62%. This study contributes to expanding the FAME profile database and highlights the potential of E. gracilis in Indonesia as a biodiesel source, particularly in the context of ecological modifications such as light spectrum optimization. The findings underline the organism's viability as a sustainable biofuel source, supporting efforts toward renewable energy development.

Dairy farming has a detrimental effect of wastewater that can pollute the environment, leading to eutrophication from increased nitrogen and phosphorus levels. Microalgae have significant potential for treating such wastewater. This study aimed to examine the influence of dairy farm wastewater concentrations on Euglena gracilis, particularly its growth, biomass, and lipid production and to develop a growth model for it. This study cultivated Euglena gracilis in Cramers & Myers (CM) medium for 18 days with wastewater concentrations of 0%, 10%, 25%, and 50%. The highest cell density, biomass, and lipid content were 64.5 x 10⁴ cells/mL, 0.560 g/L, and 0.175 g/L, respectively, in the 0% wastewater treatment. The 10% concentration yielded the best results, achieving a cell density, biomass, and lipid content of 27.0 x 10⁴ cells/mL, 0.290 g/L, and 0.127 g/L, respectively. The mathematical approach used shows that the Gompertz Model growth curve produces better simulation data than the Logistic Model. The Gompertz Model can describe Euglena gracilis cultivation with higher accuracy by accounting for the lag phase. Optimal wastewater concentration, to increase microalgae productivity, is an important aspect that can support a circular bioeconomy by using biomass as a raw material for high value products.

This study investigated the potential of anaerobic digestate effluent (ADE) as a nutrient source for cultivating Euglena sp. and Chlorella sp. ADE was applied at varying dilution levels to create distinct carbon-to-nitrogen (C/N) ratios and assess their effects on microalgal growth and nutrient removal. The research included an acclimatisation phase using a mixture of 75% Walne medium and 25% ADE to facilitate adaptation, followed by cultivation with ADE dilutions without added nutrients. This mixture supported optimal initial growth, indicating ADE’s viability as a nutrient source. Post-acclimatisation, three ADE dilution treatments established distinct C/N ratios: P1 (8.24 ± 1.32), P2 (6.47 ± 1.15), and P3 (4.39 ± 0.41), with P0 (Walne medium) as control. One-way ANOVA and Duncan’s Multiple Range Test (DMRT) revealed significant differences among treatments. Both species adapted to ADE, showing optimal growth at a C/N ratio of 6.47 ± 1.15 (P2). Under controlled conditions (28 ± 1 °C, pH 7.5 ± 0.2, 20 days cultivation), P2 achieved the highest cell density and pollutant removal. Euglena sp. removed 81.44 ± 1.40% Chemical Oxygen Demand (COD), 84.25 ± 0.79% Biological Oxygen Demand (BOD₅), 61.16 ± 2.60% Total Suspended Solid (TSS), and 88.86 ± 2.25% Ammonium (NH₄⁺-N), while Chlorella sp. achieved 89.02 ± 0.84% COD, 87.33 ± 1.34% BOD₅, 64.73 ± 3.33% TSS, and 89.45 ± 1.29% NH4⁺-N. P2’s superior performance was attributed to its balanced nutrient profile and reduced inhibitory effects associated with higher organic and ammonium levels in less-diluted ADE. These findings support ADE as a sustainable medium for microalgal cultivation, enabling biomass production and effective wastewater treatment. Optimising dilution enhances growth and environmental outcomes, underlining microalgae’s role in the circular bioeconomy and sustainable agriculture.

Elevating blood glucose levels in fish is a common approach employed to assess the efficacy of feed additives in reducing blood sugar. Glucose induction (GI) can induce oxidative stress and metabolic problems in fish, causing damage to their development and health. The potential of Euglena sp. as a microalgal source of bioactive chemicals that enhance health requires additional investigation for its application as a functional feed. Rasbora lateristriata, with significant economic potential, is an appropriate model for this study due to the clear observability of its glucose metabolism response. This study investigates the impact of incorporating Euglena sp. as a dietary supplement on growth performance, digestive histology, and the reduction of body sugar levels. Five experimental diets and treatments were developed in this research: baseline feed (C); basal feed with glucose induction (CN); basal feed with 1% Euglena (E1); basal feed with 1% Euglena and glucose induction (GIE1); and basal feed with 2% Euglena and glucose induction (GIE2). The results indicate that Euglena sp. feed can enhance growth performance by improving digestive efficiency and mitigating metabolic stress. The E1 treatment yielded the maximum growth in terms of weight gain (WG), specific growth rate (SGR), and ultimate length, with values of 46.67 ± 0.17% (seven times the control), 2.08 ± 0.08 (seven times the control), and 53.67 ± 2.17 mm, which is 19% more than the control. The following ranking includes GIE1 and GIE2, both GI treatments that induce metabolic stress; however, they yield excellent results compared to the control group when Euglena sp. is incorporated. The intestinal histology showed the best results in treatment, with Euglena sp. being added as E1, GIE1, and GIE2, which had absorbance areas of 81,403.32 µm2, 66,622.22 µm2, and 51,166.50 µm2, respectively. The GIE1 treatment led to the greatest reduction in blood sugar, with GIE2 following closely behind. Furthermore, Euglena sp. shows promise as a functional feed by increasing growth rates, improving digestion, lowering blood glucose levels, and speeding up the recovery from metabolic stress in living things. This suggests that it should be studied more for possible future uses.

Euglena sp. contains several metabolites that play a role in various sectors, likely biofuels, food, feed, and pharmaceuticals. Multiple treatments are required to increase the content of Euglena sp.to support its use. In this study, a chemical stimulant in the form of lignosulfonate was added to Euglena sp. in order to increase its natural potency as measured by lipid, carbohydrate, protein, paramylon content, and biomass productivity. Lignosulfonate is a macromolecular polyelectrolyte and anionic surfactant that is unique and multifunctional. This lignosulfonate can act as an emulsifier, dispersing agent, binder, and stabilizer of lipids in Euglena sp. cells. In addition to the lignosulfonate chemical stimulator, it can affect the growth process of Euglena sp. so that it can produce good-quality cells. The method used was a Completely Randomized Factorial Design (CRD) with three treatments and three replications. The results obtained indicated that the addition of lignosulfonate was significantly changed the cell and protein density tests. Therefore, the optimal concentration of lignosulfonate can be used as an agent to increase the growth rate and metabolites of Euglena sp. significantly. Keywords: Biofuel Euglena sp. Growth rates lignosulfonate Metabolites

Accurately predicting growth phases in microalgae cultivation is crucial for optimizing biomass production. IoT systems provide convenience in monitoring the cultivation environment in real time. However, the specific challenge of predicting microalgae growth phases still needs to be effectively addressed using IoT-based sequential monitoring data. This study introduces a novel architecture, the Feature-Enhanced Multistream Recurrent Neural Network (FEM-RNN), integrated with an IoT microalgae monitoring system to predict the growth phase of cultured microalgae, especially Euglena sp. species. The proposed method utilizes a dual channel architecture of recurrent neural networks to assess temporal environmental data, i.e., turbidity, temperature, and light intensity, acquired by the IoT system. One channel leverages all input features, while the other is specified for turbidity data. The proposed model was evaluated using a primary dataset collected by an IoT monitoring system from microalgae cultivation in outdoor environments. Three versions of FEM-RNN, i.e., utilizing the base model of Vanilla RNN, LSTM, and GRU, have been assessed in various sizes of window data. The performance of the FEM-RNN models increases with expanding the window size. All the variant models demonstrate high performance at window size 60, and the LSTM-based FEM-RNN demonstrates outstanding performance and stability beginning at the window size. At the size of the window, model performance has been compared to the traditional model, namely Vanilla RNN, LSTM, and GRU models, as well as CNN, Transformer, and SVM. The results show that the proposed model outperforms the conventional models, with an accuracy of 0.978, 0.989, and 0.951 for FEM-RNN based on Vanilla RNN, LSTM, and GRU, respectively. The results indicate that the FEM-RNN effectively predicts the microalgae growth phase utilizing IoT-based monitoring data.

Data imputation is crucial for handling missing data in order to ensure the correctness and reliability of the microalgae cultivation monitoring system, particularly for further analysis using the monitoring data. This paper presents a hybrid model called PCHIP-HW, which combines the Piecewise Cubic Hermite Interpolating Polynomial (PCHIP) and Holt-Winters (HW) methods for data imputation. The imputation consists of two stages: the initial stage uses PCHIP, while the latter stage involves decomposition using Holt-Winters, resulting in the generation of season, trend, and level. The second imputation stage involves using PCHIP interpolation to estimate the missing data values for the trend and level of the initial missing data position. Therefore, the interpolation is done based on the missing data index. Afterwards, the imputed data is combined with the season to create the final imputed data. An evaluation was conducted by examining the performance of the PCHIP-HW model under different artificial of the missing value ranges in comparison to the PCHIP approach. The results indicate that PCHIP-HW outperforms traditional PCHIP in all evaluated ranges of missing values. The excellence of PCHIP-HW is evident in its ability to handle empty data and process microalgae data effectively. The outstanding capability enables the generation of complete data for various advanced analysis objectives.

Importance of the work: A cost-efficient, phosphate fertilizer-based medium could improve the economic feasibility of Euglena gracilis Klebs, 1883 production for food industry applications. Objectives: To assess the effect of different phosphate fertilizer types on the growth and antioxidant activity of the indigenous isolate E. gracilis IDN22. Materials and Methods: Batch cultivation (150 L) of the local isolate E. gracilis IDN22 was conducted in separate tanks for each treatment, using media supplemented with various phosphate fertilizers: triple super phosphate (TSP), diammonium phosphate (DAP), monoammonium phosphate (MAP) and fused magnesium phosphate (FMP). Technical replicates (n = 3) were collected for the analysis. The observed variables were: cell growth (measured using a Neubauer counting chamber); biomass production (using the filtration method); pigment concentration and productivity (analyzed using spectrophotometry); and antioxidant activity (assessed using the 2,2 diphenyl-1-picrylhydrazyl method based on half maximal inhibitory concentration (IC50) values). Results: The DAP treatment produced the highest cell density in the exponential phase on day 13, while the MKP treatment had the highest growth rate (µmax = 0.736). In contrast, the FMP treatment had the highest values for biomass content, pigment productivity and absolute pigment. In addition, the MKP treatment had the highest antioxidant activity (IC50 = 4.172 mg/mL), while FMP had the lowest antioxidant activity (IC50 = 12.647 mg/mL). Main finding: The findings offer a scientific basis for selecting fertilizers that support sustainable and efficient microalgae production for food industry applications.

Microalgae Spirulina (Arthrospira platensis) contains high protein content (55–70 %), consisting of approximately 20 % phycocyanin compounds as a photosynthetic pigment. Phycocyanin has antioxidant and anti-inflammatory properties. This study provides valuable insights involved mass transfer modelling and stability test of phycocyanin extract, leading to several important findings. Phycocyanin yield increases with temperature until 55 °C, beyond which denaturation reduces yield, highlighting the need for optimal temperature control during extraction. In the study at temperatures ranging from 30 °C to 50 °C, the mass transfer coefficients (kca) values ranged from 0.0229/min to 0.2592/min, the effective diffusivity (De)​ values ranged from 0.112 to 0.0519 cm²/min or 1.87 × 10⁻⁸ to 8.64 × 10⁻⁸ m²/s, and the equilibrium constants (K) values ranged from 106 to 572. The mathematical modelling of mass transfer phenomena was validated through comparison with experimental data, and all models showed R-squared (R²) values greater than 0.99, indicating a strong fit. Statistical analysis confirms temperature significantly impacts mass transfer parameters (kca, De, K) in phycocyanin extraction (p < 0.05). Narrow confidence intervals for kca and De indicate high precision, while K shows greater variability, suggesting additional influencing factors besides the temperature. The mass transfer parameter constants increased with temperature due to enhanced molecular collisions, which accelerate solute diffusion and transport within the extraction medium. The degradation behavior of phycocyanin over seven days demonstrates that light exposure significantly accelerates the degradation process of bioactive compounds derived from microalgae. According to the kinetic modelling, the highest R² value among the three reaction rate models was observed for the first-order reaction rate equation, hence indicates that the first-order reaction rate equation accurately represents the degradation of phycocyanin pigment.

The feasibility of microalgae-derived products became a major issue on an industrial scale. Mixed culture is one of the improvements that can be made. The mixed culture of Glagah Strain Consortium and Monoraphidium sp. was investigated in terms of biomass, lipid, protein, and carbohydrates production, as well as productivity. Glagah Strain Consortium is a local consortium strain composed primarily of Cylindrospermopsis sp., Cyclotella sp., Corethron sp., Golenkinia sp., Chlamydomonas sp., and Syracosphaera sp., native to Glagah Lagoon in Yogyakarta, Indonesia. The mixed culture of Glagah Strain Consortium and Monoraphidium sp. was compared to the monocultures of Glagah Strain Consortium only and Monoraphidium sp. only. It is then found that mixed cultures can increase lipid productivity up to 0.1808±0.010 g/L/day, which is greater than monocultures. Mixing the culture with Monoraphidium sp. was shown to increase production and productivity of lipid, biomass, protein, and carbohydrates, though not as much as Monoraphidium sp. monoculture. Further research is needed to understand the mechanisms in the mixed culture and to increase the culture's production and productivity.

Society now faces a problem with environmental pollution, primarily due to industrial pollution. Mercury is a poisonous pollutant with a widespread distribution that settles in ecosystems. Numerous traditional methods have been used to clean mercury contamination. Bioremediation is one potential and eco-friendly method of reducing toxicants by using organisms. Phycoremediation uses algae, such as Euglena sp., in its process. This research aimed to analyze the growth, productivity, photosynthetic pigments, and Superoxide dismutase activity of Euglena sp. and analyze the kinetic model of mercury content in Euglena sp. using Pseudo-First-Order and Pseudo-Second-Order equations in the Free Water Surface-Constructed Wetlands (FWS-CW) system. This research shows that Euglena sp. chlorophyll a, chlorophyll b, carotenoid, and total chlorophyll content decrease at the lowest level at a concentration of 15 ppm. SOD activity of Euglena sp. increased with the increase of mercury stress. However, it was insignificant for the concentrations of 5 ppm, 10 ppm, and 20 ppm. The growth and productivity of Euglena sp. decrease with the increase of mercury stress. These experiences happen because Euglena sp. carries out a detoxification process. The mercury phycoremediation process by Euglena sp. is more suitable with the Pseudo-Second-Order kinetic model with an R2 value of 0.43. These results indicate that Euglena sp. can potentially be a phycoremediation agent of mercury with a maximum mercury concentration of 15 ppm.

The transition from fossil fuels to sustainable renewable energy is currently growing rapidly. Euglena sp. can be the source of biofuel. Molasses, in addition to Euglena sp., can increase the levels of paramylon and wax esters produced. Therefore, this study aims to analyze cell growth, lipid profile, and wax ester content of Euglena sp. cultivated under mixotroph conditions with molasses. Euglena was cultivated under mixotrophic conditions with the addition of various concentrations of molasses (0, 10, 15, and 20 g/L) until the final log phase. Then, measurements were made on cell density, levels of lipids, proteins, and paramylon to measure the growth and metabolites profile of Euglena sp., along with lipid profile and wax ester analysis using GC-MS. The results of the study showed that 10 g/L molasses increased Euglena growth (SGR 0.1736± 0.0213 mg/ml) and carbohydrate (0.426 mg/ml) but reduced lipid accumulation (2.29 mg/ml). This treatment provides the best result before control. Molasses does not increase carbohydrates and protein but increases paramylon accumulation. The GC-MS assay detected more lipid profiles and concentrations of each lipid type in non-molasses-treated Euglena sp. compared to molasses-treated. Euglena was cultivated on molasses, which was dominated by palmitic acid and myristyl myristate with the absence of PUFA-type fatty acids in the cells, while the untreated ones were dominated by stearic acid and myristyl myristate. Thus, 10 g/L supplementation of molasses is the most effective treatment compared to others.

The potential of microalgae as a renewable feedstock for biofuel production has attracted growing interest. Among these, Euglena sp. is considered a promising candidate due to its high lipid content and flexible growth characteristics. However, large-scale cultivation remains limited by low productivity and the high cost of conventional culture media. This study examines the synergistic effect of tofu wastewater and the plant growth regulator naphthalene acetic acid (NAA) on the growth, biomass, lipid, and pigment production of Euglena sp. The experimental treatments included 2.5 ppm NAA with 35 mL of tofu wastewater (P1), 5 ppm NAA with 60 mL of tofu wastewater (P2), and 7.5 ppm NAA with 85 mL of tofu wastewater (P3). Cell growth was analyzed through the hemocytometer cell count method. The biomass measurement was done through differential analysis. Pigment amount was measured using the Pruvost method with modifications. Lipid production calculations were performed using the modified Bligh and Dyer method. The P3 treatment showed the highest specific growth rate (0.416 cells/mL/day), lipid productivity (0.157 mg/mL/day), and pigment production, including carotenoids (0.473 µg/mL/day), chlorophyll a (2.360 µg/mL/day), and chlorophyll b (0.471 µg/mL/day). Interestingly, the control group yielded the highest biomass (0.222 mg/mL/day), indicating a potential tradeoff between biomass accumulation and biochemical productivity. These results suggest that the combination of tofu wastewater and NAA offers a cost-efficient and sustainable approach to enhancing microalgal growth and metabolite production. Further studies are recommended to optimize the cultivation system and evaluate its feasibility at a commercial scale.