Emulsion Formulation Assays Based on Natural Substances Stimulating Hair Growth and Evaluation of Its Biological Activity

The study aimed to identify the physicochemical parameters for stable emulsions using medicinal plant extracts and evaluate their hair growth-stimulating activity. Emulsions were prepared with Hibiscus rosa-sinensis L. flower extracts, Cannabis sativa L. seed oil, Ricinus communis L. oil, Olea europaea oil, and beeswax, and tested in vivo on Cavia porcellus L. for 28 days. The results showed that a water-oil emulsion with a 4/6 ratio, a Hydrophilic/Lipophilic Balance (HLB) of 7, and an average globule size of 2.57 ± 1.91μm, particularly with 10mg/g of Cannabis sativa L. seed oil and Hibiscus rosa-sinensis L. extract, exhibited good stability and stimulated capillary growth. The study concluded that the stability of such emulsions depends on the hydrophilic/lipophilic balance, uniformity of globule distribution, and the hydrophilic/lipophilic ratio.