Heat Stress Resistance in Chlorella vulgaris Enhanced by Hydrolyzed Whey Proteins

Plant biologists have long used various model organisms, such as Arabidopsis thaliana, to study biological processes. The emergence of algal model organisms in recent years greatly facilitated plant research due to their compact genomes with a very low level of functional redundancy and their physiological properties. Here, the green microalga Chlorella vulgaris has been used as a model organism to study the effect of whey hydrolysates against heat stress in vascular plants. Cell density in culture, as well as chlorophyll and carotenoid concentrations, were monitored during an initial growth phase, followed by a heat stress phase and a subsequent recovery phase. Results showed that whey hydrolysates promoted the recovery of heat-stressed C. vulgaris and showed improved growth rates and generation times after heat stress compared to cells grown in BG-11 only. Similarly, the production of chlorophyll a, chlorophyll b, total chlorophyll and total carotenoids was improved in comparison to cells grown only in BG-11. The results may aid the development of novel biostimulants that protect crops from climate change due to higher throughput and shorter study times compared to traditional plant models.