Species identification of stranded seaweeds on eastern seashores of Thailand and utilization as a sole carbon source for single cell oils synthesized by oleaginous yeasts

Abstract

Abstract. Chantarasiri A. 2020. Species identification of stranded seaweeds on eastern seashores of Thailand and utilization as a sole carbon source for single-cell oils synthesized by oleaginous yeasts. Biodiversitas 21: 2353-2361. Many stranded seaweeds are left to decompose on the seashore. This study aimed to identify and utilize the stranded seaweeds collected from seashores in Rayong Province on the east coast of Thailand. Seaweeds were identified as Dictyota dichotoma strain A and Padina australis strain B based on their distinctive morphology and 18S rDNA sequence analyses. The most abundant seaweed, D. dichotoma strain A, was analyzed for chemical compositions following AOAC standard methods. This seaweed was considered a low-cost carbon source for the cultivation of three oleaginous yeasts without any other nutrient supplements. All oleaginous yeasts utilized the carbon source from Dictyota medium for growth and accumulation of single-cell oils (SCOs). The oleaginous yeast, Cryptococcus albidus strain TISTR 5103 accumulated SCOs at 51% (w/w). The resulting SCOs from oleaginous yeasts comprise many fatty acids with 10 to 22 carbon atoms. This study is the first to identify stranded seaweeds in Rayong Province using morphological and genetic techniques. Results showed the potential application of stranded seaweeds as a low-cost carbon source for SCO biosynthesis of oleaginous yeasts.

The oleaginous yeast Pichia manshurica isolated from Lansium domesticum fruit in Thailand and its fatty acid composition of single cell oil

“…The lipid accumulating isolates capable of the SCO storage over 20% (w/w) of their dry cell mass was considered as oleaginous yeast. The determination of the dry cell weight of the lipid accumulating yeasts was conducted by Chantarasiri (2020). Harvested yeast cells were resuspended in 0.85% (w/v) of sterilized NaCl solution and filtered through a preweighed 0.45-µm nitrocellulose filter (Millipore, USA) using a vacuum pump (Millipore, USA).…”

“…The SCO concentration was defined as the amount of extracted SCO per liter working volume (g/L), and the SCO content was represented as a percentage of the dry cell weight (%, w/w) (Chantarasiri 2020). The positive control of this experiment was an oleaginous yeast Y. lipolytica strain TISTR 5212 (Thailand Institute of Scientific and Technological Research, Thailand).…”

“…Microbial lipids produced by oleaginous microbes are called single cell oils (SCOs). Microbe species that are considered oleaginous can accumulate more than 20% (w/w) of their dry biomass under suitable cultivation conditions (Jiru et al 2016;Gientka et al 2017;Chantarasiri 2020). These types of microbes belong to yeasts, filamentous fungi (e.g., Aspergillus oryzae, Cunninghamella echinulate, Mortierella alpina, Mortierella isabellina, and Mucor sp.…”

“…A large variety of oleaginous yeasts can be found in several environments; such as, common surfaces, fruit products, plant surfaces, and soil (Polburee et al 2015;Vincent et al 2018). The effective oleaginous yeasts belong to the genera Candida, Cryptococcus, Lipomyces, Rhodosporidium, Rhodotorula, Trichosporon, and Yarrowia (Dey and Maiti 2013;Jiru et al 2016;Gientka et al 2017;Patel et al 2017;Qin et al 2017;Ayadi et al 2018;Lopes et al 2018;Chantarasiri 2020). The lipid content of yeasts may vary and reach up to 70%, depending on the species and certain nutrient-limited conditions (Sreeharsha and Mohan 2020).…”