BOTANICAL CORE: ABSTRACT/SUMMARY The overall purpose of the Botanical Core of the proposed University of Mississippi (UM) Botanical Dietary Supplements Research Center (BDSRC) is to ensure product integrity and advance chemistry research on the Spirulina-based product, Immulina™, using a combination of bioassay- and chemical-based approaches. Researchers affiliated with the proposed UM BDSRC have generated evidence that supports reproducible and mechanistically plausible effects of Immulina™ for enhancing host responses that may promote resilience against respiratory viral infections such as influenza which resulted in 959,000 patient hospitalizations and 79,400 deaths in United States alone. The Botanical Core will be headed by Amar Chittiboyina, PhD, a medicinal chemist with extensive research experience in natural product chemistry as well as standardization methodologies. The specific aims of the Botanical Core are to: 1. Ensure the unambiguous identification and develop additional safety testing on Arthrospira (Spirulina) platensis raw material that will be used in the production of sufficient quantities of Immulina™ for the proposed research projects; 2. Develop and validate a selective in vitro bioassay for quantitation of the toll-like receptor 2-dependent activity exhibited by the Braun-type lipoproteins in Immulina™; 3. Advance chemistry research on Immulina™ by establishing chemical-based authentication and standardization approaches, characterization of immune-inhibitory substances and detailed structural analysis of the active immune-enhancing Braun-type lipoproteins; and 4. Perform additional stability studies, provide sufficient quantities of well-characterized and safe ImmulinaTM for use in the proposed UM BDSRC research projects, and explore collaborative opportunities with other CARBON units. Expected outcomes include (1) achieving a higher level of product integrity and quality assurance of Immulina™ used in the proposed UM BDSRC projects; (2) design of an improved biological standardization method that will selectively detect only TLR2 agonists such as the Braun-type lipoproteins in Immulina™; (3) providing chemical-based authentication and standardization methods that will complement the bioassay-based standardization method and provide a robust system to fully characterize Immulina™ product material; and (4) to provide sufficient quantities of standardized Immulina™ working closely with other researchers from the UM BDSRC and collaborating with other units of CARBON on future efficacy studies of ImmulinaTM.