Production and characterization of nanoparticles containing methanol extracts of Portuguese Lavenders

Lavenders (Lavandula species) are aromatic plants of great economic value for fragrance, pharmaceutical and cosmetic industries. Their biological activities and application on therapy can be compromised due to bioactive compounds physicochemical instability. Therefore, nanotechnology can be used as a way of achieving this stabilization.The antioxidant profile of different extracts from Lavandula stoechas ssp. luisieri and L. pedunculata were established by lipid peroxidation inhibition and the antioxidant activity confirmed by the free radical scavenging method. Methanol extracts of L. stoechas ssp. luisieri and L. pedunculata, due to their high antioxidant activity, phenolic content (1387.21 and 1044.19 mg gallic acid equivalents gsample−1, respectively) and flavonoid amount (482.4 and 360.0 mg rutin equivalents gsample−1) were selected for encapsulation. The produced polymeric poly (lactic-co-glycolic) acid (PLGA) nanoparticles observed by scanning electron microscopy (SEM) showed a well-defined spherical shape and a high encapsulation efficiency (>96%) when the concentration of the extracts main component, rosmarinic acid, was used as indicator of encapsulation efficiency.The epidermal permeation of both extracts through human epidermis and their in vitro cytotoxicity in human keratinocytes studies were suggestive of low risks of toxicity. In conclusion, the current study provides data for promising new cosmetic or dermatological formulations for the pharmaceutical industry, as anti-aging and antioxidant agents.