Which purity of Glabridin (40%, 90%, 98%) is best for cosmetic formulas?

As a product developer tasked with expanding our brand’s skincare portfolio, I am evaluating the cost-to-efficacy ratio of different botanical skin brighteners. I see that your factory offers Glabridin in 40%, 90%, and 98% purities. I need a comprehensive breakdown of which specification is best suited for different cosmetic applications. Our goal is to formulate a mass-market body lotion as well as a high-end targeted dark spot corrector. I need to understand exactly how each purity level impacts the final formula’s color, raw material BOM (Bill of Materials) cost, and overall melanin-inhibiting performance so we can make an informed procurement decision.