Unilever files patent on prebiotic scalp care formula targeting dandruff

Writing in its international patent filing​​, Unilever outlined a novel use of trehalose in a formulation that promoted scalp health, more specifically as a prebiotic to inhibit the fungus Malassezia restricta ​typically found at higher levels in cases of dandruff. The composition, it said, could be used in a range of leave-on or rinse-off products, including hair creams, hair serums, foams and even shampoos.

‘Effectively’ treating the common scalp disorder dandruff​

The personal care major said that were already several prebiotic topical skin care compositions designed to interact with existing microorganisms on the body’s surface – many created by other major beauty players. However, there remained a clear need for a composition that targeted scalp care, more specifically dandruff, it said.

“[Dandruff] is a common scalp disorder affecting many people with the symptoms of shedding, itching and visible flakes on the scalp,”​ Unilever wrote in its patent filing.

And in dandruff cases, levels of the fungus Malassezia restricta​ were “significantly higher”​ compared to a healthy scalp, it said, so reducing the levels of this fungus was considered “one of the effective approaches to effectively treat dandruff”.​

Unilever’s patent outlined one such method to achieve this – using the disaccharide threhalose as a prebiotic that interacted with Staphylococcus hominis​ naturally present on the scalp’s surface to inhibit ailment-inducing microorganisms, in this case Malassezia restricta​ [M. restricta​].

“We have found that disaccharides, preferably trehalose, is effective against ​M. restricta as [a] prebiotic and thereby inhibits dandruff to promote scalp health,” ​the company wrote.​

Unilever previously filed a separate international patent on a rinse-off shampoo it said also targeted dandruff​ by reducing the level of Malassezia restricta​ on the scalp. Filed in 2020, that formulation used a combination of the well-known anti-fungal agent piroctone olamine and coconut oil.

Beyond scalp care – deodorants, sunscreens and wipes​

Unilever said use of the disaccharide as a prebiotic also offered promise beyond scalp care, for topical beauty products targeting other ailment-inducing microorganisms, most notably Staphylococcus aureus ​that was associated with various adverse effects on skin health. ​Beauty formulation opportunities included deodorants, lipsticks, mascara, sunscreen lotions, skin lotions and even body wipes.

“Trehalose, in the presence of ​S. hominis, is effective against the ailment inducing microorganisms like ​Malassezia restricts and ​Staphylococcus aureus,” ​Unilever said. “Therefore, it is clear (…) that trehalose can effectively be used as a prebiotic for inhibiting ailment-inducing microorganisms when applied on an external surface of a human body.”​

The company previously filed a separate international patent in 2020 on a ‘microbiome balancing’ topical formula that used saccharide isomerate as a prebiotic​. This formula, it said, could also be used in a range of products, including deodorants, hand sanitisers, body lotions and sprays and even toothpaste.

In its latest patent filing, Unilever said the topical composition preferably contained trehalose at 0.1 – 5% by weight of the composition, no matter what product formulation it was used in. For leave-on formulations, the topical was preferably an emulsion and for rinse-off formulations, an acceptable surfactant base was required.

Unilever outlined specific formulation requirements for use in deodorants and sunscreens in its patent.

Source: WIPO International Patent No. WO/2022/008163​​
Filed on: June 11, 2021. Published on: January 12, 2022.
Title: “Use of trehalose as prebiotic for inhibiting ailment inducing microorganisms”​
Inventor: Unilever – CC. Chu, M. Pu, Q. Yin and X. Yue