Abstract Ankistrodesmus sp. belongs to a group of microalgae which plays a significant role in various applications. Availability of nutrients is one of the primary factors regulating the growth and development of microalgae. Twelve experiments were run to determine the optimum media formulation of significant nutrient components for maximum biomass and lipid productivities of Ankistrodesmus sp. IFRPD 1061 cultivation using Plackett- Burman design. All nutrients significantly affected biomass pro- ductivity. Highest lipid productivity may not only necessarily originate from biomass cells with highest lipid content but also depend on nutrient formulation of culture media. Microalgal cell growth rate plays a major role in biomass and lipid production. Some nutrients including phosphorus and sodium did not signifi- cantly affect lipid productivity, therefore, optimizing nutrient con- tents could be applied to further scale-up microalgal production. Introduction Microalgae are photosynthetic cyanobacteria and eukaryotic microorganisms that grow rapidly and can live in different environ- ments due to their unicellular or simple multicellular structure and simple growth needs. They are a potential source of many important components such as lipids, proteins, carbohydrates, and mono and polyunsaturated fatty acids. 1 Microalgae produce lipids, proteins, and carbohydrates that can be processed into both biofuels and valu- able co-products. They can replace large volumes of crude oil and supply demands for food supplements, animal feed, colorants, enzymes, and several other valuable chemicals. 2 Commercial bio- mass production of feedstock can reduce nonessential nutrient com- position, with large scale reductions in production costs. 3 Microalgal growth depends on environmental conditions including light, temperature, carbon source, salinity, pH, and nutrients. 4 One of the most important factors affecting biomass productivity is the composition of nutrients in microalgal culture. Many species of microalgae have been reported as potential alternative sources of biodiesel feedstock including Chlorella sp., Synechococcus sp., Schizochytrium sp., and Chlorococcum sp. 4,5 Moreover, Ankistrodesmus sp. offers an interesting freshwater microalgal cultivation for fast-growing (2.5 doubling a day) lipid production. 6 Several studies have highlighted the potential of Ankistrodesmus sp. for biodiesel production with high lipid pro- ductivity. 7 Preliminary screening of potential high lipid produc- tion from several fresh microalgal strains was studied. Ankistrodesmus sp. IFRPD 1061 gave highest lipid content and productivity among other fresh microalgal strains. 8 Ankistrodesmus sp. is a green phototrophic microalga which has a long crescent shape with a slight curve at both ends. 9 Characteristics of cells were observed as individually clustered or twisted around each other. Ankistrodesmus sp. follows asexual reproduction, whereby parent cells divide to produce a new cell. The parental cell wall ruptures to release 1-16 spores that develop into the new cell. 6 Microalgal cultivation can provide a diverse number of essential nutrients. Combining the abilities of microal- gae to grow rapidly and produce more biomass than plants can Correspondence: Wanida Pan-utai, Department of Applied Microbiology, Institute of Food Research and Product Development, Kasetsart University, Bangkok 10900, Thailand. Tel. +6683.136.4554 - Fax: +662.940.6455. E-mail: ifrwdp@ku.ac.th Key words: Microalgae; Nutrient; Biomass; Lipid; Plackett-Burman design. Contributions: WP and PS conceived and designed the experiments. WP and WI collected samples and performed laboratory and data analyses. WP interpreted the data and drafted the manuscript. WP, PS and WI participated in discussions and provided suggestions. All authors read and approved the final manuscript. Conflict of interest: the authors declare no potential conflict of interest. Acknowledgments: this study was partially supported by the Kasetsart University Research and Development Institute (KURDI), Thailand. Thanks to the Institute of Food Research and Product Development (IFRPD), Kasetsart University for supporting the research instrument. Partial aspects of the screening of nutrient composition are protected by petty patent numbers 1703000705 and 1703004929 under the Kasetsart University license. Received for publication: 9 September 2019. Revision received: 23 October 2019. Accepted for publication: 25 October 2019. © Copyright: the Author(s), 2019 Licensee PAGEPress, Italy Journal of Biological Research 2019; 92:8547 doi:10.4081/jbr.2019.8547 This article is distributed under the terms of the Creative Commons Attribution Noncommercial License (by-nc 4.0) which permits any noncommercial use, distribution, and reproduction in any medium, provided the original author(s) and source are credited. [Journal of Biological Research 2019; 92:8547] [page 95] Journal of Biological Research 2019; volume 92:8547 Nutrients formulation to maximize Ankistrodesmus sp. microalgal cell biomass and lipid productivities Wanida Pan-utai, 1 Penjit Srinophakun, 2 Wilasinee Inrung 3 1 Department of Applied Microbiology, Institute of Food Research and Product Development, Kasetsart University, Chatuchak, Bangkok; 2 Department of Chemical Engineering, Faculty of Engineering, Kasetsart University, Chatuchak, Bangkok; 3 Faculty of Agro-Industry, King Mongkut’s Institute of Technology Ladkrabang, Bangkok, Thailand Non-commercial use only