Development of ointment formulations prepared with Achyrocline satureioides spray-dried extracts

Achyrocline satureioides spray-dried extracts, prepared with colloidal silicon dioxide, microcrystalline cellulose + colloidal silicon dioxide (1:1), and beta-cyclodextrin + colloidal silicon dioxide (1:1), were incorporated in a glyceryl monostearate base. The influence of the spray-drying adjuvants on the formulations' physical characteristics, such as spreading properties, oil indexes, viscosities, and the pH determination, were evaluated. The results indicated that the adjuvants influenced the ointments' physical parameters at different levels, although all of them maintained their plastic flow and presented antithixotropic behavior. The presence of colloidal silicon dioxide alone, in the dried extract, imparted the lowest oil index value and an intermediary spreading area to the ointment. The colloidal silicon dioxide content reduction and the substitution of part of it by beta-cyclodextrin or microcrystalline cellulose enhanced the ointments' oil index values, while the best spreading area was reached by the ointment prepared with the spray-dried extract containing colloidal silicon dioxide and microcrystalline cellulose.