Transfer pattern of hormesis into personal care product mixtures from typical hormesis-inducing compounds

Some personal care products (PCPs) and their chemical components showed a hormetic effect in the freshwater photobacterium Vbrio qinghaiensis sp. -Q67 (Q67) after long-term exposure. However, how hormesis transfers between chemical components and PCP mixture, and which chemical component plays a major role remain unknown. 'lb this end, according to the seven compounds detected in one skin lotion (SKS) and their concentration ratios, many mixture rays were constructed to simulate the SKS. Of these seven compounds, three presented monotonic concentration-response curves (CRC) to Q67 at 0.25 and 12 h (called a S-shaped compound). The other four compounds showed hormetic CRCs after 12 h and monotonic CRCs at 0.25 h (called a J-shaped compound). Based on their mixture ratios, we designed one ternary mixture ray of all S-shaped compounds, one quaternary mixture ray of all J-shaped compounds, and four quaternary mixture rays of one J-shaped and three S-shaped compounds. It was shown that SK5 could be approximately simulated by the mixture ray of the seven compounds detected in SK5 and only the mixture rays containing at least one hormesis-inducing compound produced hormesis to Q67 at 12 h. Based on the concentration ratios of various compounds and comparison of four hormetic characteristic parameters to those of various mixture rays, it was found that the compound betaine (BET) is a key compound affecting the hormesis of mixtures. Additionally, we studied the hormesis mechanism of BET on Q67 via quorum sensing (QS). This preliminarily indicated that the autoinducer-2 triggered the QS pathway. This study elucidated the transfer pattern of hormesis into mixtures, which would be an efficient method to identifying the potential components that affect hormesis transfer in mixtures. We expect that this study will provide new insights into hormesis and its mixtures.

Automated summary

This study investigates the transfer of hormesis between chemical components and personal care product mixtures and identifies a key compound, betaine, affecting hormesis transfer. The study finds that only mixture rays containing at least one hormesis-inducing compound produce hormesis to the freshwater photobacterium Q67. The study also suggests that betaine triggers the quorum sensing pathway, contributing to hormetic effects. This research provides new insights into hormesis and its mixtures, and offers an efficient method to identify potential components that affect hormesis transfer in mixtures.