Anti-aging potential of a cream containing milk thistle extract: Formulation and <i>in vivo</i> evaluation

Abstract

This study was designed to formulate and evaluate antı-agıng effects of a topical cream (water in oil (w/o) emulsion) containig extract of milk thistle (Silybum marianum) against its vehicle (Base) as control. Base containing no extract and a formulation containing 4% concentrated extract of Silybum marianum was developed by entrapping in the inner aqueous phase of w/o emulsion. Both the base and formulation were stored at 8°C 0.1°C (in refrigerator), 25°C 0.1°C, 40°C 0.1°C and 40°C 0.1°C with 75% RH (in incubator) for a period of 8 weeks to predict their stability. The evaluation parameters consisted of colour, smell, type of emulsion, electrical conductivity, liquefaction and pH. The expected organoleptic stability of creams was acheived from 8 weeks in-vitro study period. The formulation and base were evaluated for effects on skin moisture and transepidermal water loss (TEWL). The base showed insignificant (p≥0.05) while formulation showed significant effects on skin moisture and TEWL. The surface evaluation of living skin (SELS) parameters SEr, SEsc, SEsm and SEw were also evaluated which showed significant decline proving that the formulation possesses potential antiaging effects.

Key words: Silybum marianum, W/O emulsion, emulsion stability, transepidermal water loss (TEWL), surface evaluation of living skin (SELS).