Cocrystals to tune oily vitamin E into crystal vitamin E

d-alpha-tocopherol (d-alpha Toc), the most biologically active form of natural Vitamin E, is oily in appearance and unstable to oxygen. Esterification and encapsulation are generally needed to stabilize and solidify d-alpha Toc for the purpose of its expanding applications. In this study, we propose a more effective way to stabilize and solidify d-alpha Toc oil in one step. By cocrystallization, the melting point of d-alpha Toc is significantly increased, such that the oily d-alpha Toc is successfully transformed into solid form at room temperature. The single crystal structure of d-croc was firstly uncovered and the molecular interaction in cocrystals was revealed. Crystalline Vitamin E shows high stability to light and temperature. Its spherical crystallization affords good powder flowability, which is extremely important as food or feed additives. Moreover, cocrystal Vitamin E remains the original form of tocopherol without esterification and thus has a great advantage on higher bioavailability. Cocrystallization of oily d-alpha Toc spares the use of acetic ester and a mass of excipients, which is of great environmental importance and greatly reduces the production cost.

Automated summary

This study introduces a more effective method to stabilize and solidify d-alpha-tocopherol oil through cocrystallization, increasing its stability and transforming it into solid form.