Facilitating astaxanthin precursor accumulation in Limnospira platensis through nitrogen-doped carbon dots synthesized from bovine serum albumin.

BACKGROUND

Astaxanthin is widely recognized as one of the most potent natural antioxidants. However, the large-scale production of astaxanthin remains a significant challenge due to the limitations of current chemical and biosynthetic methods. To address these challenges, this study explores the use of nitrogen-doped carbon dots (N-CDs) to enhance the accumulation of astaxanthin precursors (such as β-carotene and zeaxanthin) in Limnospira platensis.

RESULTS

The N-CDs exhibited excellent dispersibility, strong blue photoluminescence, and no detectable cytotoxicity. By optimizing cultivation parameters such as N-CDs concentration (10 mg L-1), temperature (26 °C), light intensity (4500 lx), and nitrogen-limited medium (NaNO3 1.25 g L-1), effective improvements in biomass yield and bioactive compound accumulation were achieved. Under these optimized conditions, the biomass yield (1.48 ± 0.06 g L-1), β-carotene accumulation (1.20 ± 0.01 g kg-1), and zeaxanthin accumulation (0.43 ± 0.02 g kg-1) increased by 140.32%, 96.72%, and 95.45%, respectively, compared to the control.

CONCLUSION

These findings demonstrate that N-CDs can serve as a cost-effective strategy for enhancing bioactive compound production in Limnospira platensis, offering a novel and efficient approach for biotechnological applications related to natural antioxidant production. © 2026 Society of Chemical Industry.