Pre-clinical and cellular safety assessment of oral administered DHA rich microalgae oil from Schizochytrium sp. (Strain ATCC-20889): acute, sub-chronic and genotoxicity

Abstract

The lack of toxicity data for DHA-rich oil from Schizochytrium sp. (Strain ATCC-20889) leads to its exclusion from the Qualified Presumption of Safety list. Therefore, present study addresses toxicity evaluation of DHA-rich microalgae oil using ex-vivo (cytotoxicity assay) and in-vivo methods (acute (OECD 423 guidelines), sub-chronic (OECD 452 guidelines), and genotoxicity assay). The ex-vivo results showed >90% cell viability of Caco-2 cells after 48 h of treatment (200 µg/mL of DHA). Additionally, the in-vivo acute toxicity study found that microalgae oil was nontoxic and classified under category 5 molecule according to OECD 423 guidelines with a highest degree of safety at 2000 mg/kg b.w. The in-vivo sub-chronic study revealed no significant mortality and changes in feed intake, body weight, haematological, biochemical, neurological, and urine parameters after repeated 180-days administration of DHA-rich microalgae oil at 250 mg/kg, 500 mg/kg, and 1000 mg/kg. Moreover, histopathology evaluation, comet assay, chromosomal aberration, and micronuclei assay also confirmed the nontoxic behavior of DHA-rich oil. Thus, the results from the ex-vivo and in-vivo studies indicate that DHA-rich oil from Schizochytrium sp. (Strain ATCC-20889) is safe for use as a novel food, and can be included in infants, adults, pregnant women, and children formula.

Keywords:

• Acute oral toxicity
• 180-day sub-chronic oral toxicity
• Docosahexaenoic acid
• Genotoxicity
• ATCC-20889

Acknowledgement

The authors are thankful to Department of Science and Technology for providing fund for Improvement of S&T Infrastructure (DST-FIST) to Department of Pharmaceutical sciences, Guru Nanak Dev University. (Letter no. SR/FST/LSI-657/2016(C). Authors are also grateful to Indian Council of Medical Research, New Delhi for providing the financial support under the ICMR-SRF scheme (project no. 2020–8721).

Disclosure statement

No potential conflict of interest was reported by the author(s).

Data availability statement

Data available within the article or its supplementary materials.

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Funding

The author(s) reported there is no funding associated with the work featured in this article.