Exploration of microalgae from Tasik Tun Telanai reveals Ankistrodesmus sp. as a high-lipid-yielding species despite non-optimized cultivation and extraction

Sustainable use of local microalgal resources holds strong potential for bioenergy, food security, and carbon-reduction efforts. To address the need for locally sourced, high-lipid microalgae with global relevance, we evaluated the lipid recovery of strains under practical, non-optimized conditions, which may improve the economic feasibility of microalgal-derived products. Among the isolates, Ankistrodesmus sp., a freshwater microalga from Tasik Tun Telanai of Universitas Jambi, was identified as the highest-lipid-yielding species. Ankistrodesmus sp. was observed to have the highest resilience and most consistent growth, producing a notably higher lipid content of 34.58 ± 2.95% dry weight (DW) compared with Chlamydomonas sp. (7.00 ± 0.25% DW) and Coelastrum sp. (8.92 ± 0.13% DW) under the same non-optimized cultivation and extraction conditions. GC-MS analysis revealed that its lipid is primarily composed of hydrocarbons (47.12%), followed by fatty acids (30.07%) and fatty alcohols (14.74%). The hydrocarbons mainly consisted of pentacosane isomers (34.94%), while monounsaturated fatty acids predominated, with oleic acid isomers (C 18 H 34 O 2 ) accounting for 11.1% of total lipids. Brine Shrimp Lethality Test (BSLT) preliminary data showed no toxicity for Ankistrodesmus sp. and Chlamydomonas sp. lipids (LC 50 > 1000 ppm), supporting potential feed and food applications, whereas Coelastrum sp. lipids showed low toxicity (LC 50 = 264.96 ppm). This study finds that Ankistrodesmus sp. is a highly promising local microalgal strain capable of producing high lipid yields without cultivation or extraction optimization, supporting its potential for scalable biofuel and sustainable bioproduct development. • First characterization of microalgae and lipids from Tasik Tun Telanai. • Ankistrodesmus sp. identified as a highly lipid-rich local microalgae strain. • Lipid profile of Ankistrodesmus sp. dominated by long-chain hydrocarbons. • Non-fatty-acid lipid classes detected in Ankistrodesmus sp. for the first time. • First toxicity assessment shows Chlamydomonas sp. and Ankistrodesmus sp. lipids are non-toxic.