Light and Nutrient Conditions Influence Fucoxanthin Production of the Microalgae _Cyclotella meninghiana_  
[PERSON]  
1 Guangdong Provincial Key Laboratory of Marine Disaster Prediction and Prevention, Shantou University, Shantou 515063, China; [EMAIL_ADDRESS] (S.C.); 2 [EMAIL_ADDRESS] (J.C.); [EMAIL_ADDRESS] (Y.L. ); 20 [EMAIL_ADDRESS] (YS. ); 2 [EMAIL_ADDRESS] (K.C. ); [EMAIL_ADDRESS] (H.D. ); [EMAIL_ADDRESS] (W.L.) [PERSON]  
1 Guangdong Provincial Key Laboratory of Marine Disaster Prediction and Prevention, Shantou University, Shantou 515063, China; [EMAIL_ADDRESS] (S.C.); 2 [EMAIL_ADDRESS] (J.C.); [EMAIL_ADDRESS] (Y.L. ); 20 [EMAIL_ADDRESS] (YS. ); 2 [EMAIL_ADDRESS] (K.C. ); [EMAIL_ADDRESS] (H.D. ); [EMAIL_ADDRESS] (W.L.) [PERSON]  
1 Guangdong Provincial Key Laboratory of Marine Disaster Prediction and Prevention, Shantou University, Shantou 515063, China; [EMAIL_ADDRESS] (S.C.); 2 [EMAIL_ADDRESS] (J.C.); [EMAIL_ADDRESS] (Y.L. ); 20 [EMAIL_ADDRESS] (YS. ); 2 [EMAIL_ADDRESS] (K.C. ); [EMAIL_ADDRESS] (H.D. ); [EMAIL_ADDRESS] (W.L.) [PERSON]  
2 South China Sea Environmental Monitoring Center, State Oceanic Administration, Guangzhou 510300, China; [EMAIL_ADDRESS]  
[PERSON]  
1 Guangdong Provincial Key Laboratory of Marine Disaster Prediction and Prevention, Shantou University, Shantou 515063, China; [EMAIL_ADDRESS] (S.C.); 2 [EMAIL_ADDRESS] (J.C.); [EMAIL_ADDRESS] (Y.L. ); 20 [EMAIL_ADDRESS] (YS. ); 2 [EMAIL_ADDRESS] (K.C. ); [EMAIL_ADDRESS] (H.D. ); [EMAIL_ADDRESS] (W.L.) Key words and phrases:Fucoxanthin, phrases:Fucoxanthin, phrases:Fucoxanthin, phrases:colon,  
The trade-based production of fucoxanthin relies on brown macroalgae [17]. In industrial applications, seaweed has the disadvantages of scarcity, low growth rates, less fucoxanthin, and poor product quality, making it an expensive and unsustainable original material for practical production [18; 19; 20]. The fucoxanthin production in macroalgae is still reliant on collection from wild populations (68% of macroalgae production units) and is limited by fucoxanthin yields (less than 3.7 mg g\({}^{-1}\) DW) and long incubation periods [21; 8; 22]. Microalgae are characterized by their high biomass productivity, fast growth rate, accessibility and cultivation, ease of scale-up, and continuous supply of stocks, which can help them to scale up industrial production, improve the controllability and sustainability of production, and utilize resources more efficiently [23; 24]. Numerous studies have highlighted the variance in fucoxanthin levels between macroalgae and microalgae, noting that microalgae possess a notably greater fucoxanthin concentration compared to macroalgae (up to 100 times that of seaweed) [6; 23; 24; 25; 26; 27]. These characteristics make microalgae more suitable than macroalgae as promising candidates as a reliable source of commercially produced fucoxanthin [6; 24]. Previous studies have shown that the amassment of fucoxanthin in microalgae is critically influenced by light and nutrients, with the cumulative content varying among different species [28; 29; 30]. For instance, among the cells of _Isochrysis galbana_ under different nitrogen concentrations, those in medium containing 4 mM nitrogen (N-NO\({}_{3}\)) had the largest fucoxanthin content, which was 18.8 mg g\({}^{-1}\)[31]. Similarly, research conducted on _Odontella aurita_ revealed that cells under initial high nitrogen plus supplementary nitrogen conditions maximized the fucoxanthin accumulation: a maximum productivity of 6.01 mg L\({}^{-1}\) d\({}^{-1}\)[32]. Another study obtained a maximum yield of 50.5 mg L\({}^{-1}\) of fucoxoxanthin from _Poterioochromomas mallamentnsis_ CMBB-1 by coupling light with high-cell-density fermentation [28]. Microalgae may act as a consistent and dependable supplier of natural goods, with their effectiveness amplified by the corresponding target compounds [33]. Consequently, exploring how various environmental elements influence the build-up of fucoxanthin in microalgae becomes crucial.