Effects of Different Nitrogen and Phosphorus Ratios on the Growth, Nutritional Value, and Nutrient Removal Efficiency of Wolffia globosa

Abstract

This study investigates the influence of varying nitrogen-to-phosphorus (N:P) ratios on the growth, nutritional composition, and nutrient removal efficiency of Wolffia globosa under controlled laboratory conditions. Six treatments with N:P ratios of 1:3, 1:2, 1:1, 2:1, 3:1, and a control were evaluated. The findings indicate that a balanced N:P ratio (1:1) promotes optimal growth, resulting in the highest biomass yield and specific growth rate (SGR = 0.120 g/day). In contrast, a nitrogen-rich ratio (3:1) enhanced protein accumulation and phosphorus removal, while the 2:1 ratio favored nitrogen uptake. These results reflect underlying physiological responses, including nitrogen assimilation and phosphorus uptake mechanisms regulated by nutrient balance. A trade-off was observed between biomass production and phosphorus removal efficiency, suggesting that different N:P ratios may be suited to specific application goals. This study contributes to a more comprehensive understanding of how macronutrient balance affects growth and metabolism in W. globosa and offers practical implications for optimizing its use as both a sustainable protein source and a biological agent for nutrient remediation in wastewater treatment systems.

1. Introduction

Wolffia globosa (duckweed or water meal) is an aquatic plant in the Lemnaceae family and the smallest flowering plant in the world. It has attracted significant attention, with the global duckweed protein market valued at USD 72.7 million in 2024 [1]. W. globosa has been selected as a critically important alternative protein source to address future nutritional needs, with outstanding nutritional value and minimal environmental impact. It requires minimal land, water, and energy inputs, while producing high protein yields, containing up to 40% protein in dry weight [2,3,4], comparable to many plant-based protein sources. Additionally, it contains essential amino acids, unsaturated fatty acids, and beneficial minerals, making it a valuable food source for both humans and animals [5,6,7]. With protein content equivalent to traditional protein sources but produced more efficiently and sustainably, W. globosa plays a crucial role in transitioning to a more sustainable food production system [8,9]. The appeal of W. globosa extends beyond its nutritional value to its cultivation characteristics. It has a rapid growth rate, capable of producing high biomass in a short period, especially when grown under optimal conditions [10]. Beyond being a food source, W. globosa is widely used in wastewater treatment due to its ability to absorb nutrients like nitrogen (N) and phosphorus (P), helping reduce excess nutrients in wastewater and mitigate water pollution [11,12,13]. Lemnaceae family plants are efficient at removing nitrogen and phosphorus from wastewater, with multiple studies exploring W. globosa’s phytoremediation potential [14,15]. Despite its high potential as an alternative protein source and wastewater treatment agent, research on optimal cultivation conditions, including environmental factors and nutrient composition, remains limited. Generally, W. globosa cultivation is conducted in open systems or natural ponds [16] in environments suitable for growth. However, environmental factors such as light intensity, aeration, and nutrient concentration significantly impact W. globosa growth patterns [10].

In Thailand, W. globosa is cultivated in both outdoor soil ponds and indoor systems. However, open system cultivation has significant limitations, such as environmental contamination and uncontrollable environmental changes [17]. These limitations result in unstable W. globosa production. Consequently, commercial W. globosa cultivation in closed greenhouse systems with controllable cultivation parameters has gained increased attention. Indoor cultivation methods include concrete ponds, plastic ponds, and plastic water trough systems with water recirculation, which are gaining increasing popularity. Fertilizers used in indoor cultivation typically employ commercially available balanced formulas, such as NPK 15:15:15 or 16:16:16 [18]. However, research on specific macronutrient requirements for W. globosa, particularly the effects of nitrogen and phosphorus on growth and nutritional composition, is still insufficient [7,19]. Some studies suggest that increasing phosphorus levels may stimulate protein synthesis, though, in certain cases, it may reduce biomass accumulation [20]. Conversely, appropriate nitrogen ratios can enhance chlorophyll synthesis and promote plant growth [14,15]. However, knowledge about the optimal N:P ratio for maximizing biomass yield and nutrient absorption efficiency in W. globosa remains limited [7,19,21], highlighting the need for further investigation into specific nutrient requirements and ratios.

Therefore, this study aims to investigate the effects of different N:P ratios on growth, nutritional composition, and nutrient removal efficiency of W. globosa. The findings will be crucial for developing optimal culture medium formulations to enhance commercial Wolffia cultivation in the future.

2. Materials and Methods

2.1. Plant Material and Experimental Setup

W. globosa was sourced from an indoor concrete pond commercial farm located in Nakhon Ratchasima province, Thailand. Upon receiving the samples, they were initially placed in plastic containers filled with clean water, positioned in a shaded area with continuous air circulation. Prior to the experiment, a meticulous selection process was conducted, carefully separating W. globosa with light green coloration and removing all other contaminants, retaining only the specimens with fresh, vibrant green appearance. The experiment was conducted under controlled conditions using five different nutrient treatments with varying N:P ratios: T1 (1:1:0.5), T2 (2:1:0.5), T3 (3:1:0.5), T4 (1:2:0.5), and T5 (1:3:0.5). This study followed a completely randomized design (CRD), with each treatment replicated three times (

Table 1. Nutrient formulations used in W. globosa cultivation experiment.

Treatment	Ratio	Nitrogen (g)	Phosphorus (g)	Potassium (g)
T1	1:1:0.5	0.69	0.69	0.28
T2	2:1:0.5	0.92	0.46	0.28
T3	3:1:0.5	1.03	0.35	0.28
T4	1:2:0.5	0.46	0.92	0.28
T5	1:3:0.5	0.35	1.03	0.28

).

2.2. Preparation of Nutrient Solutions

The nutrients used in this experiment were food-grade nutrients, selected based on the primary nutrients (NPK) used for W. globosa cultivation. The fertilizers chosen for the experiment comprised urea (CH₄N₂O) (46-0-0), monocalcium phosphate monohydrate (Ca(H₂PO₄)₂ H₂O) (0-46-0), and potassium sulfate (K₂SO₄) (0-0-50+S). These fertilizers were precisely weighed and mixed to achieve the desired N:P:K ratios, as shown in Table 1. Nutrient solutions were prepared at a concentration of 0.11 g/L, equivalent to 1.65 g per 15 L of water in each experimental tray.

2.3. Cultivation Method

The experimental trays were made of black plastic, measuring 34 × 46 × 10 cm³, and were used for cultivation (see Supplementary Figure S1). Nutrient-mixed water was added to all experimental groups (n = 15), according to the experimental design in Figure 1. The stocking rate of W. globosa was set at 200 g/m². Given the tray surface area of 0.15 m², 30 g of W. globosa were placed in each experimental tray. These trays were positioned to receive natural light during morning hours (06:00–10:00 am) with continuous air circulation.

2.4. Growth Performance of W. globosa

Growth performance evaluation was conducted through a sampling process throughout the 15-day experimental period. Samples were collected every three days to track the growth characteristics of W. globosa. During each sampling interval, the entire biomass from each experimental tray was carefully collected using a fine mesh net to ensure comprehensive and uniform sampling. The collected biomass was weighed using a digital scale with 0.01 g precision to record the wet weight. After weighing, W. globosa was carefully returned to its original tray to maintain the continuity of the cultivation process and minimize the impact on the growth environment.

At the end of the 15-day experimental period, the collected weight data were used to calculate growth rate and specific growth rate (SGR) for comparative analysis across different experimental groups. The specific growth rate (SGR) calculation formula according to the method of Phatarpekar et al. [22] is as follows:

$$\mathrm{SGR}=(\mathrm{In}{W}_t-\mathrm{In}{W}_0)/t$$

(1)

where W_t is the final weight (g), W₀ is the initial weight (g), and t is the experimental period in days. Growth rates were compared among experimental groups.

2.5. Nutritional Composition Analysis of W. globosa

W. globosa samples were collected using a fine mesh net at every point in the tray. Water samples were collected before drainage for nutrient removal efficiency analysis. Water gradually drained through the outlet, with a fine mesh placed over the outlet to prevent W. globosa from escaping. Collected W. globosa samples were transferred to pre-weighed containers and their wet weight was measured from each tray. A total of 50 g (wet weight) of W. globosa was placed in sealed plastic bags and stored in a refrigerator at 4 °C for subsequent nutritional analysis. A total of 50 g (wet weight) of W. globosa from each experimental group was dried at 70 °C for 48 h and used for nutritional analysis. The assessment included measuring moisture, crude protein, fat, ash, and crude fiber content. Crude protein content was determined by Kjeldahl technique. Moisture, ash, and crude fiber content were analyzed using the AOAC [23] method, while the fat content was determined using the Gerhardt Soxtherm methods [24].

2.6. Nutrient Removal Efficiency

Water samples were collected before and after W. globosa cultivation from each treatment group for analysis of nitrogen (N) concentration using the 4500-N B. Macro-Kjeldahl Method and phosphorus (P) concentration using the 4500-P E. Ascorbic Acid Method [25]. Nutrient removal efficiency was calculated using initial and final nutrient concentrations as follows:

$$\mathrm{Nitrogen} \mathrm{removal} \mathrm{efficiency} (\%)=\left[{\displaystyle \frac{\left(\mathrm{Initial} \mathrm{N} – \mathrm{Final} \mathrm{N}\right)}{\mathrm{Initial} \mathrm{N}}}\right]\times 100$$

(2)

$$\mathrm{Phosphorus} \mathrm{removal} \mathrm{efficiency} (\%)=\left[{\displaystyle \frac{\left(\mathrm{Initial} \mathrm{P} – \mathrm{Final} \mathrm{P}\right)}{\mathrm{Initial} \mathrm{P}}}\right]\times 100$$

(3)

2.7. Statistical Analysis

Statistical analysis of W. globosa growth was performed using one-way analysis of variance (ANOVA) and comparison of mean differences between experimental groups using Scheffé’s test with a 95% confidence level (p < 0.05) for accepting statistical significance. All statistical calculations and analyses were performed using IBM SPSS statistics version 22.

3. Results

3.1. Evaluation of Growth Performance of W. globosa

In this study, we investigated the influence of different nitrogen-to-phosphorus (N:P) ratios on the growth dynamics of W. globosa, with particular attention to biomass accumulation and specific growth rate and observed that the growth of W. globosa differed significantly among treatments by day 10 of the experiment (

Table 2. Growth performance of W. globosa cultivated with different N:P ratios over a 10-day period.

Treatment	Culture Periods (day)					SGR (g/day)
	0	3	6	9	10
T1	30.21 ± 0.74	35.93 ± 4.00	47.50 ± 3.18	77.03 ± 3.33 a	98.73 ± 0.81 a	0.120
T2	30.21 ± 0.74	35.40 ± 4.16	46.47 ± 2.68	64.5 ± 3.25 ab	77.90 ± 2.97 b	0.095
T3	30.21 ± 0.74	34.63 ± 4.01	41.97 ± 5.36	56.40 ± 3.44 b	71.40 ± 4.93 b	0.089
T4	30.21 ± 0.74	36.80 ± 3.14	48.47 ± 3.00	75.80 ± 6.41 a	92.37 ± 4.50 a	0.115
T5	30.21 ± 0.74	34.70 ± 1.05	47.83 ± 5.46	71.07 ± 3.25 a	90.97 ± 3.00 a	0.113

Note: values within the same column with different superscripts are significantly different (p < 0.05).

). T1 exhibited the highest biomass accumulation (98.73 g), though not significantly different (p > 0.05) from T4 (92.37 g) and T5 (90.97 g). However, T1 showed a significant difference (p < 0.05) compared to T2 (77.90 g) and T3 (71.40 g), which exhibited lower growth. Regarding specific growth rate (SGR), the results indicated that the optimal N:P ratio for enhancing W. globosa growth was 1:1 (T1), yielding the highest SGR (0.120 g/day). Conversely, T3 had the lowest SGR (0.089 g/day), suggesting that excess nitrogen may reduce W. globosa growth efficiency.

3.2. Nutritional Composition Analysis

In this study, we conducted a detailed assessment of the chemical composition changes in W. globosa, with particular attention to protein, fat, carbohydrate, fiber, and ash content, and observed the following significant statistical differences among experimental treatments (

Table 3. Nutritional composition of W. globosa cultivated under different N:P ratios.

Proximate Composition (%)	Treatments
	T1	T2	T3	T4	T5
Moisture	95.51 ± 0.04 ab	95.34 ± 0.06 a	95.56 ± 0.08 bc	95.71 ± 0.06 c	95.91 ± 0.07 d
Dry matter	4.50 ± 0.04 ab	4.66 ± 0.06 a	4.44 ± 0.08 bc	4.30 ± 0.06 c	4.09 ± 0.07 d
Ash	19.45 ± 0.07 c	16.60 ± 0.11 b	14.66 ± 0.15 a	22.67 ± 0.20 d	22.41 ± 0.24 d
Protein	33.36 ± 0.16 c	35.99 ± 0.62 d	38.68 ± 0.01 e	29.33 ± 0.06 b	27.52 ± 0.19 a
Fat	6.29 ± 0.22 ab	6.40 ± 0.11 a	5.60 ± 0.10 c	5.87 ± 0.03 abc	5.78 ± 0.09 bc
Carbohydrate	72.81 ± 0.19	73.67 ± 0.59	72.85 ± 0.30	73.84 ± 2.43	71.16 ± 1.07
Fiber	9.21 ± 0.07	10.02 ± 1.25	9.47 ± 0.44	11.68 ± 2.23	11.37 ± 1.02

Note: values within the same row with different superscripts are significantly different (p < 0.05).

).

Protein content analysis revealed notable variations, with T3 exhibiting the highest protein content (38.68 ± 0.01%), followed by T2 (35.99 ± 0.62%), T1 (33.36 ± 0.16%), T4 (29.33 ± 0.06%), and T5 (27.52 ± 0.19%). All groups showed statistically significant differences (p < 0.05). The T3 treatment, with a NPK ratio of 3:1:0.5, suggests a potential relationship between N:P ratios and protein synthesis.

Fat content also demonstrated statistically significant differences (p < 0.05) between experimental groups. T2 showed the highest value (6.40 ± 0.11%), followed by T1 (6.29 ± 0.22%), T4 (5.87 ± 0.03%), T5 (5.78 ± 0.09%), and T3 (5.60 ± 0.10%), with T2 and T3 showing statistically significant differences (p < 0.05).

Carbohydrate and fiber contents showed no significant differences among treatments (p > 0.05), with carbohydrate values ranging from 71.16 ± 1.07% to 73.84 ± 2.43% and fiber content ranging from 9.21 ± 0.07% to 11.68 ± 2.23%.

Ash content, representing the total mineral composition, exhibited significant differences (p < 0.05). T4 showed the highest value (22.67 ± 0.20%), followed by T5 (22.41 ± 0.24%), T1 (19.45 ± 0.07%), T2 (16.60 ± 0.11%), and T3 (14.66 ± 0.15%), with experimental groups showing lower phosphorus proportions displaying reduced ash quantities.

3.3. Analysis of Nutrient Removal Efficiency

Nitrogen and phosphorus are key nutrients with a crucial role in aquatic plant growth. Studying nitrogen and phosphorus removal efficiency provides insights into W. globosa’s ability to utilize nitrogen and phosphorus. In this study, we found that nitrogen removal efficiency (NRE) varied among experimental treatments, with T2 demonstrating the highest efficiency (48.52%), followed by T1 (47.50%) and T3 (43.55%). In contrast, T4 (21.98%) and T5 (22.73%) exhibited lower nitrogen removal efficiencies (Figure 2a). However, no statistically significant differences were detected among the treatments (p > 0.05).

Phosphorus removal efficiency (PRE) showed significant differences among treatments (p < 0.05). T3 exhibited the highest phosphorus removal efficiency (30.73%), followed by T4 (23.55%), T2 (22.41%), and T5 (16.38%). T1 displayed the lowest efficiency (6.85%), significantly lower than all other treatments (Figure 2b).

This study revealed the trade-off relationship between growth rate and nutrient removal efficiency. Specifically for phosphorus, an inverse relationship was observed between growth rates and phosphorus removal efficiency (PRE). Groups with higher growth rates exhibited lower phosphorus removal rates, conversely, groups with increased phosphorus removal efficiency demonstrated lower growth rates. However, across all experimental treatments, no clear trade-off was detected between growth and nitrogen removal efficiency (NRE) (Figure 2c).

These findings demonstrate that nutrient ratios significantly influence W. globosa growth, nutritional composition, and nutrient absorption efficiency, providing valuable insights for optimizing cultivation strategies and commercial applications.

4. Discussion

This study demonstrated the influence of different nitrogen-to-phosphorus (N:P) ratios on the growth, nutritional composition, and nutrient removal efficiency of Wolffia globosa. The results confirmed that optimizing N:P ratios plays a crucial role in enhancing biomass production, improving nutritional value, and increasing nutrient absorption efficiency. These findings can be applied to develop sustainable aquatic plant cultivation systems and efficient wastewater treatment processes. Besides nutrient ratios, other critical environmental factors such as light intensity, water temperature, pH, and overall water quality play significant roles in the growth and metabolism of aquatic plants [14]. For instance, light intensity affects photosynthetic rates, with W. globosa generally thriving under low light conditions [18], while temperature impacts enzyme functioning and metabolic processes [19]. pH influences nutrient solubility and absorption, and electrical conductivity can also affect growth dynamics [21]. Although these factors were not controlled or measured in this research, they should be considered in future studies to provide a more comprehensive understanding of W. globosa responses under diverse environmental conditions.

Growth rate and biomass accumulation differed significantly among experimental groups. This study investigated the growth rate of W. globosa, revealing distinct growth phases over the experimental period. The first phase, spanning days 3–6, represented the adaptation period to the new growing environment. On day 3 of the experiment, W. globosa across all treatment groups exhibited similar weights with no statistically significant differences (p > 0.05). This uniformity resulted from the plants’ initial adaptation process, with some W. globosa experiencing mortality, characterized by white-colored plants scattered throughout the experimental trays [26]. By day 6, W. globosa had successfully adapted to the new environment, demonstrating budding and dispersal across the experimental trays [27]. At this stage, no significant differences were observed between experimental groups (p > 0.05). On day 9, statistically significant differences emerged between experimental groups (p < 0.05), likely attributable to variations in nutrient formulations received by W. globosa. This study was unexpectedly concluded on day 10 (instead of the planned 15 days) due to observations in treatments T1, T4, and T5 showing a decline in growth. This decline was attributed to the high density of W. globosa filling the experimental trays, limiting further expansion. As W. globosa proliferates on water surfaces through budding and relies on wind for dispersal [26], excessive density leads to a self-suppression density-dependent response typical in these aquatic plants [28]. In terms of biomass accumulation, it was observed that treatment T1 (N:P = 1:1) yielded the highest biomass production (98.73 g) and the highest specific growth rate (SGR = 0.120 g/day), indicating that a balanced nitrogen and phosphorus ratio promotes optimal W. globosa growth [15,19]. This observation aligns with the principle that balanced N:P ratios, such as 1:1, provide sufficient nitrogen for chlorophyll synthesis and adequate phosphorus for the production of ATP and nucleic acids, facilitating efficient energy transfer, cell division, and biomass accumulation [19,21]. In contrast, T3 (N:P = 3:1), which had the highest nitrogen content, resulted in the lowest biomass accumulation (71.40 g) and the lowest SGR (0.089 g/day), possibly due to excessive nitrogen causing nutrient imbalances, limiting phosphorus absorption and restricting biomass synthesis [14]. Additionally, this experiment revealed that all groups exhibited significant growth increases between days 9 and 10 before growth began to decline. This suggests that W. globosa may reach saturation earlier than the standard 14-day harvest period typically used in conventional cultivation systems [18]. Optimizing nutrient provision could accelerate growth and shorten cultivation cycles, benefiting commercial production by increasing yield per unit time and improving system management efficiency.

The nutritional composition of W. globosa was significantly affected by N:P ratios. T3 (N:P = 3:1) had the highest protein content (38.68%), as nitrogen plays a vital role in protein synthesis via amino acid formation and nitrogen metabolism [7,21]. However, the protein content and biomass in group T3 resulted from high nitrogen levels stimulating amino acid synthesis, leading to increased protein accumulation through nitrogen absorption mechanisms [7,19,21]. This explains why group T3 (N = 3:1) had the highest protein content, despite low biomass production. It demonstrates that W. globosa tends to accumulate protein more than increasing cell numbers, indicating that elevated nitrogen levels do not necessarily promote growth in terms of biomass. Conversely, T1 (N:P = 1:1) exhibited the highest carbohydrate content (73.67%), suggesting that a balanced nitrogen and phosphorus supply enables efficient energy conversion into carbohydrates [29]. Meanwhile, T5 (N:P = 1:3), which had the highest phosphorus content, showed the highest ash content (22.41%), likely due to mineral accumulation under high phosphorus conditions [6]. In the analysis of W. globosa fat content, a narrow range of fat percentages (5.60–6.40%) was observed, which may indicate an optimal nutrient balance for lipid metabolism. This suggests that W. globosa can maintain a stable lipid profile under different nutrient conditions [30].

N:P ratios also influenced nutrient removal efficiency. T2 (N:P = 2:1) exhibited the highest nitrogen removal efficiency (48.52%), consistent with previous research indicating that moderate nitrogen levels enhance nitrogen absorption and protein synthesis in aquatic plants [12,14]. However, T3 (N:P = 3:1) had lower nitrogen removal efficiency (43.55%), possibly due to excessive nitrogen leading to absorption limitations [15]. This may be explained by a decline in nutrient uptake efficiency under high nitrogen conditions, resulting from feedback inhibition of nitrate transporters or transporter saturation, as reported in previous studies [12,21,31]. For phosphorus removal, T3 exhibited the highest efficiency (30.73%), suggesting that high nitrogen levels stimulate phosphorus uptake to maintain intracellular N:P homeostasis [11]. This phenomenon has been reported in duckweed species, where high nitrogen availability triggers compensatory phosphorus uptake to rebalance cellular nutrient ratios, thus explaining the observed increase in phosphorus removal efficiency under nitrogen-rich conditions [14,19,32]. In contrast, T1 (N:P = 1:1) had the lowest phosphorus removal efficiency (6.85%). A clear trade-off was observed between growth and phosphorus removal efficiency: conditions that favored high growth resulted in lower phosphorus removal, whereas conditions that maximized phosphorus removal led to reduced growth. This aligns with findings by Chikuvire et al. [32], who reported that Lemna minor exhibited decreased phosphorus removal efficiency under rapid growth conditions. Similarly, Petersen et al. [19] suggested that increasing the nitrogen-to-phosphorus ratio can enhance phosphorus absorption in aquatic plants, albeit at the cost of biomass accumulation. Notably, no clear trade-off was observed between growth and nitrogen removal efficiency. T1 exhibited both robust growth and efficient nitrogen removal (47.50%), likely because nitrogen plays a central role in plant metabolism, chlorophyll synthesis, and amino acid formation, allowing direct utilization for growth [7,32,33].

The findings indicate that different N:P ratios are suitable for distinct applications. The N:P ratio of 1:1 (T1) is optimal for maximizing biomass production and nitrogen removal, making it ideal for cultivating W. globosa as an alternative protein source while treating nitrogen-rich wastewater. The N:P ratio of 3:1 (T3), despite lower biomass yield, is more effective for phosphorus removal, making it suitable for treating high-phosphorus wastewater. The N:P ratio of 2:1 (T2) provides a balanced approach for systems requiring effective removal of both nitrogen and phosphorus.

These findings highlight the potential of W. globosa as both a sustainable protein source and an efficient wastewater treatment tool [34,35,36]. Future studies should explore additional environmental factors, such as temperature, light intensity, and micronutrient availability, which may further optimize W. globosa growth and nutritional composition. Additionally, biochemical research on nitrogen and phosphorus absorption mechanisms could improve cultivation techniques. Large-scale cultivation trials are also necessary to assess commercial viability and scalability.

5. Conclusions

Different nitrogen-to-phosphorus (N:P) ratios significantly influenced the growth, nutritional composition, and nutrient removal efficiency of W. globosa. The N:P ratio of 1:1 (T1) produced the highest biomass (98.73 ± 0.81 g) with efficient nitrogen removal (47.50%) and the highest specific growth rate (0.120 g/day), making it optimal for maximizing production while treating nitrogen-rich wastewater. The 3:1 ratio (T3) demonstrated the highest phosphorus removal efficiency (30.73%) despite yielding the lowest biomass, while the 2:1 ratio (T2) provided balanced efficiency for removing both nutrients. A distinct trade-off was observed between growth and phosphorus removal efficiency, whereas nitrogen removal efficiency did not exhibit such a relationship. Nutritionally, the 3:1 ratio yielded the highest protein content (38.68%), the 1:3 ratio (T5) had the highest ash content (22.41%), and the 2:1 ratio (T2) exhibited the highest fat content (6.40%). These variations demonstrate that nutrient ratios can be adjusted to enhance specific nutritional qualities of W. globosa. These findings provide practical insights for optimizing W. globosa cultivation based on specific objectives, whether for sustainable protein production, wastewater treatment, or dual applications. The results are particularly relevant to Thailand’s emerging W. globosa industry, offering science-based strategies to enhance production efficiency and potentially shorten cultivation cycles through targeted nutrient management.