Since Fuller first defined probiotics in 1989, these live bacteria have been recognized for their ability to benefit the host by improving the balance of intestinal flora. The two core elements of probiotic supplements are "adequate quantity" and "health benefits." However, live bacteria are sensitive to storage conditions and can easily become inactive at room temperature, making it difficult to ensure their quantity under normal transportation conditions. Moreover, live bacteria may pose safety risks for individuals with immune deficiencies or the elderly, potentially causing sepsis.

In 2011, Japanese scholar Taverniti introduced the concept of "non-viable microorganisms " also known as paraprobiotics. The key features of paraprobiotics include:

• Intact cell structure but without the ability to proliferate.
• Retention of bioactive components of the cell wall.
• No need for cold chain storage; heat-inactivated strains can be stably preserved for 24 months at RT.

Paraprobiotics are typically obtained through heat treatment, preserving the molecular structure of bacterial cell wall compounds such as peptidoglycan, lipoteichoic acid, polysaccharides, and cell surface proteins. These molecules offer health benefits to humans, including immune modulation, intestinal microbiota regulation, cancer-fighting assistance, and antibacterial activity. Compared to traditional probiotics, paraprobiotics have higher safety, better stability, and a broader range of applicability.