Lavandula angustifolia NAMNAŻANA W KULTURACH IN VITRO NA POŻYWKACH ZAWIERAJĄCYCH AgNP i AuNPs – ALTERNATYWNE ROZWIĄZANIE DLA SYNTETYCZNYCH KONSERWANTÓW W KOSMETYKACH

Abstract

We determined the preservation properties of Lavandula angustifolia propagated on media with gold or silver nanoparticles with a particle size of 13 and 30 nm. Cosmetic emulsions prepared by using lavender tissue that was propagated on media containing AuNPs and AgNPs showed increased preservative capacities when compared with the control ones. In the case of control cosmetic emulsions, which had no added plant tissues or dehydroacetic acid and benzoic acid (DHA BA), bacterial and fungal colonies appeared after the second week of the experiment. The addition of lavender tissue propagated on media without AuNPs or AgNPs protected the tasted samples from microbial contamination; in this case, bacterial contamination was detected after 4 weeks and fungal contamination after 6 weeks. The addition of lavender tissue propagated on medium containing AgNPs with a particle size of 13 nm at a concentration of 1 mg · dm−3 prolonged the time of detection of bacteria colonies to 8 weeks (0.9) and this result was close and comparable to the effect of DHA BA. Higher concentrations of AgNPs in the culture medium, as well as a larger particle diameter (30 nm), resulted in the decreased preservative capacity of plant tissues. The presence of AuNPs in the culture media showed a positive effect on the antimicrobial activity of lavender; however, to a lesser degree than in the case of AgNPs. Disintegrated fragments of lavender tissue propagated on media containing 1 mg ∙ dm−3 AgNPs with particle size of 13 nm can be used to preserve short shelf life cosmetic emulsions.