Deciphering metabolomic insights into benzoic acid-mediated nutrient enrichment in Chlorella pyrenoidosa

Abstract

Chlorella pyrenoidosa, abundant in various nutrients, has importance in food health. Seeking safe and effective nutrient-promoting methods is paramount. Benzoic acid (BA) is a secondary metabolite of plants with wide functions. This study examined the impact and mechanism of BA on the biomass and nutrient of C. pyrenoidosa using the algae growth assay, biochemistry index test, and metabolomics. BA at 1 mg/L had minimal impact on algae cell growth, whereas 100 mg/L halted growth within 120 h. The highest biomass promotion was observed at 10 mg/L BA with 48 h cultivation, resulting in a 2.60 times greater biomass. Higher soluble protein and chlorophyll a (Chl-a) contents were observed 10 mg/L BA treated cells, indicating a enhanced cell activity. Metabolomics analysis demonstrated activation of carbon metabolism, and biosynthesis of cofactors, etc., and increase of metabolites like reduced glutathione, vitamine B2/B3/C, α-linolenic acid, and DHA. However, 100 mg/L BA reduced the Chl-a, and perturbed the carbon and amino acid metabolism. This study revealed the application potential of BA as a nutrient promoter of C. pyrenoidosa and enriched the biological function of BA.