Pukyong National University

Technology Developed to Boost the Production of Functional Microalgal Materials Using Light

― Pukyong National University-Korea Research Institute of Bioscience and Biotechnology Joint Research Team Confirms Simultaneous Increases in Microalgal Cell Productivity and the Production of Fucoxanthin and Omega-3 Fatty Acids under Red-Light Conditions

― Next-Generation Platform for Optimizing Microalgae Cultivation Proposed through Image-Based Single-Cell Analysis

A research team led by Professor Hyun-Ho Shin of the Major of Aquaculture and Applied Life Sciences in the Division of Fisheries Life Sciences at Pukyong National University, together with a team led by Dr. Jun Lee of the Korea Research Institute of Bioscience and Biotechnology (KRIBB), has developed a new light-based cultivation technology capable of simultaneously enhancing microalgal growth and the production of functional materials.

The joint research team conducted cultivation experiments using the marine microalga Tisochrysis lutea, combining white, red, and blue light with plant hormones. The researchers comprehensively analyzed growth characteristics, photosynthetic capacity, fucoxanthin and fatty acid production, and cellular population structure. The findings confirmed that light wavelength is a key environmental factor that regulates not only microalgal growth, but also the morphology of cell populations and the production of functional metabolites.

The research team found that microalgae cultivated under red light exhibited approximately 1.5 times higher cell productivity than those grown under white light and approximately 1.4 times higher productivity than those grown under blue light. Under red-light conditions, the production of fucoxanthin, an antioxidant functional pigment, increased by up to 1.62%, while total fatty acid production rose by up to 14.6%. In particular, omega-3 fatty acids―including DHA, a key ingredient in health functional foods and high-quality aquaculture feed―showed the highest productivity under red-light conditions.

Fucoxanthin is a natural carotenoid that has attracted attention for its various bioactive properties, including antioxidant, anti-inflammatory, and anti-obesity effects. Omega-3 fatty acids such as DHA are also high-value biomaterials widely used in health functional foods and the aquaculture industry. This study presents a strategy for efficiently producing these functional materials simultaneously under a single set of cultivation conditions.

Going beyond conventional analyses limited to biomass or pigment content, the joint research team applied image-based single-cell cytometry to analyze real-time changes in cell morphology and population structure during cultivation. The results showed that cell aggregation decreased substantially under red light, with more than approximately 97% of the total cells maintaining a uniform single-cell state. This approach is attracting attention as a new evaluation technology that could improve not only the productivity of functional materials, but also the efficiency of future large-scale cultivation and harvesting processes.

The research team also confirmed that although plant hormones had some effects on microalgal growth and metabolism, overall productivity and cellular characteristics were primarily determined by light wavelength. These findings indicate that prioritizing the optimization of the light environment is the most effective strategy for controlling the production of functional substances in microalgae.

Professor Hyun-Ho Shin said, “This study demonstrates that light wavelength can simultaneously regulate not only microalgal growth, but also cell population structure and the production of functional materials. It is particularly meaningful in that it presents a new platform for precisely evaluating microalgal cultivation conditions by incorporating image-based single-cell analysis.”

The findings were published in Bioresource Technology, a leading international journal in the fields of biomass and bioprocessing ranked in the top 3% by JCR with an impact factor of 9, under the title “Light Spectra Shape Population Structure and the Allocation of Fucoxanthin and Fatty Acids with Secondary Phytohormone Modulation in Tisochrysis lutea.”