What are the biochemical components of hibiscus oil?

Thehibiscus is a perennial plant belonging to the Malvaceae family and can grow up to five meters high. Its cultivation dates back to ancient times. Back then, the Egyptians and Asians used its fruits for their nutritional benefits, while its colorful flowers were used as ornaments.

Hibiscus vegetable oil is found in various treatments intended for skin and hair care. It is generally obtained from a cold pressing of hibiscus seeds. From an organoleptic perspective, it is a golden yellow liquid that penetrates the skin quite easily, and has a light and sweet scent with some vegetal notes.

Thehibiscus vegetable oil possesses numerous properties, which can be explained by its composition rich in active ingredients with multiple virtues.

The hibiscus vegetable oil is rich in polyunsaturated fatty acids.

Hibiscus oil is composed of approximately 40% polyunsaturated fatty acids, such as linoleic acid. This essential fatty acid belongs to the omega-6 family and cannot be synthesized by the body. From an epidermal perspective, linoleic acid indirectly contributes to the formation of the skin barrier by triggering a cascade of biochemical reactions that ultimately lead to the stimulation of cell renewal.

It also plays a role in the synthesis process of ceramides, lipids naturally present in the skin that ensure good cohesion between the cells of the epidermis. They play an important role in protecting the skin from external aggressions and dehydration.

A deficiency in linoleic acid leads to the weakening of the epidermal barrier and an increase in insensible water loss (IWL). The skin then becomes drier, rougher, and more prone to irritations. The loss of skin hydration also promotes the appearance of wrinkles and fine lines, making them more visible.

The hibiscus vegetable oil contains monounsaturated fatty acids.

Hibiscus oil also contains monounsaturated fatty acids, such as oleic acid, at approximately 20%. Belonging to the omega-9 family, it can be synthesized by the body from other fatty acids. Oleic acid is naturally present in the hydrolipidic film of the skin. This acts as a shield to keep the skin hydrated and protect it from external aggressions. This fatty acid thus has beneficial properties for skin protection, as it helps to strengthen the hydrolipidic film.

The hibiscus vegetable oil is concentrated in saturated fatty acids.

Certain saturated fatty acids, such as stearic acid and palmitic acid, also make up the composition of hibiscus vegetable oil, at about 20%. They give it a creamy texture and, their structure being very similar to that of the compounds of the epidermis, they increase its ability to penetrate the skin, giving it a dry touch.

Hibiscus oil, an extract containing a high amount of tocopherols (Vitamin E).

The tocopherols (vitamin E) are natural antioxidants. They protect skin cells from free radicals, reactive oxygen species responsible for premature skin aging. In the case of hibiscus vegetable oil, tocopherols work by transforming hydrogen peroxide (H₂O₂), which causes damage to DNA and proteins, into water (H₂O). These active ingredients thus serve as excellent allies to prevent the appearance of wrinkles and fine lines. Furthermore, tocopherols help to limit the oxidation and rancidity of hibiscus oil, providing it with a better stability over time.

Phytosterols in hibiscus oil.

Finally, hibiscus oil contains phytosterols, compounds that contribute to maintaining the skin's barrier function and have soothing properties. These molecules also have anti-inflammatory activity and regulate certain inflammation processes. However, the mechanism by which these molecules work has not yet been fully elucidated, and further research is still needed.

• HEINRICH M. & al. Hibiscus sabdariffa L. - a phytochemical and pharmacological review. Food Chemistry (2014).