An Algal Nutrient-Replete, Optimized Medium for Fast Growth and High Triacylglycerol Accumulation

Area of Science:

• * Biotechnology and Algal Research
• * Sustainable Bio-production

Background:

• * Microalgae offer sustainable solutions for global energy and product demands.
• * Chromochloris zofingiensis is a promising alga for co-producing biofuel precursors and astaxanthin.
• * Standardized experimental conditions are needed for efficient microalgal cultivation.

Purpose of the Study:

• * To design a defined, nutrient-replete medium for fast-growing Chromochloris zofingiensis.
• * To optimize nutrient conditions for mixotrophic growth, biomass, and astaxanthin production.
• * To establish a standard medium for replicable experiments and industrial applications.

Main Methods:

• * Inductively coupled plasma mass spectrometry (ICP-MS) to analyze cellular ionome.
• * Growth curve analysis with glucose (+Glc) to assess nutrient requirements.
• * Iterative adjustment of nutrient concentrations, particularly phosphorus, sulfur, and iron.

Main Results:

• * Identified high phosphorus and sulfur requirements for mixotrophic growth.
• * Developed the Chromochloris-Optimized Ratio of Elements (CORE) medium.
• * CORE medium supports rapid growth, high biomass, and lipid accumulation without toxicity.

Conclusions:

• * The CORE medium provides a standardized, nutrient-replete condition for C. zofingiensis.
• * Ionomics-informed media design enables replicable bioproduction.
• * This approach can be adapted for other microalgae species and industrial biofuel production.