Leaves extract of a Lamiaceae genus Lepechinia: screening issue and development of a new active cosmetic ingredient

Apoptosis is a physiological process leading to a programmed cell death [1]. The survivin protein, an inhibitor of apoptosis (IAP), is not expressed in differentiated tissues except the skin, especially by keratinocytes of the basal layer [2], so survivin is involved in cutaneous aging by its implication in cellular mecanism (apoptosis of keratinocytes). Screening of hundred plant extracts resulted in the selection of leaves extract of a Lamiaceae as the best activator of survivin (ELISA measurement in keratinocytes lysates after 16h of treatment with extract at 3.125µg/mL). The impact of the extraction process was studied in a second time (biological activity and organoleptical caracteristics): discoloration, type of solvent, temperature, and fractionation study.

Even if active carbon did not affect the biological activity, we chose to test different extraction solvents on the plant material, to reduce the cost and number of steps. We have demonstrated that the active compounds are extracted by the alcoholic or hydroalcoholic solvents with intermediate polarity (examples: 37% overexpression of survivin rate with ethanol/water (50/50 v/v) extract, or +15% with butanol extract).

This study allowed us to make the choice of the best solvent of extraction according to criteria of technical and economic practicability. More, in a worry of security and respect for environment, we turned to green techniques.

References: [1] Bowen, A.R et al. (2003)J. Investig. Dermatol. 120:48–55.

[2] Deveraux, Q.L. et al. (1999) Genes Dev. 13:239–252.