Investigation of the anti-inflammatory properties of Calendula nanoemulsion on skin cells

Essential oils and extracts are used in the medical field, perfumes, cosmetics and food additives. Calendula belongs to a composite family and contains small amounts of volatile essential oils, saponins, and so on. Due to these properties, there is a growing inclination and interest to use this material in the hygiene and cosmetics industry. In this study, the production of nanoemulsions was conducted using Tween 80 and Span 80 as emulsifiers. The optimum operation condition was determined using the design expert method. The obtained results showed that the optimum values of the emulsification process were 9·1, 3·4%, 4·7%, 3 min and 102 nm for hydrophile–lipophile balance (HLB), surfactant concentration, extract concentration, sonication time and nanoemulsion size, respectively. Sonication time and HLB were the main factors in the emulsification process. Also, by applying three samples (3, 5 and 7% of Calendula extract) on albino rats, the authors found that all samples had positive effects for healing and ameliorating the wounds. According to the results, the nanobioemulsion of Calendula extract showed an anti-inflammatory effect on skin cells. Therefore, Calendula nanoemulsion should be proposed to cosmetic and pharmaceutical industries instead of chemical and synthetic nanomaterials.