The application of Sapindus mukurossi extract in sebum-control shampoos

Sapindus mukurossi extract (SME) is a potential ingredient in cleaning products, but its polyphenols and pigments can easily lead to product browning and affect the amount of addition. D301 resin was used to adsorb polyphenols and oxidative decolorization to achieve industrial decolorization and increase the amount of additives. After optimizing the decolorization conditions, the color of SME was stable at high temperature and significantly reduced the lipid synthesis of SZ95 cells. Further evaluation found that shampoo containing 10% SEMs significantly reduced scalp sebum levels within 4 weeks without affecting skin moisture and transepidermal water loss (TEWL).

Sapindus mukurossi, a fruit from a deciduous tree in the Sapindaceae family, is widely cultivated in Southern China. Before the advent of modern synthetic detergents, its peel was commonly used to make soap due to its high saponin content. Saponin, a natural plant surfactant, exhibits antibacterial, anti-inflammatory and antioxidant properties, along with effective decontamination and foaming abilities. It is now widely used in daily care products, cosmetics, and other industries.

In industrial production, saponins are typically extracted using traditional methods like water or alcohol extraction. However, these extracts also contain impurities such as polyphenols, flavonoids and pigments, which can cause browning due to oxidation, particularly by polyphenols. This browning significantly limits the use of S. mukorossi extract (SME) in high-end products. Therefore, developing an effective decolorization process is crucial to minimize color impact and enhance the applicability of SME in various industries.

In a new study published in the Volume 1, Issue 2 of Journal of Dermatologic Science and Cosmetic Technology, a team of researchers from China and Germany developed a decolorization process involving resin adsorption and oxidative decolorization was developed to address this issue. The researchers also investigated SME's sebum-control efficacy using the SZ95 model and clinical studies.

“SME was prepared by adsorbing polyphenols on the D301 resin and oxidation decoloring oxidation,” shares Jing Wang, senior and co-corresponding author of the study. “D301 resin was found to have the best adsorption selectivity for polyphenols in SME.”

In particular, optimal decolorization conditions were determined to be at pH 7.8 at 73 °C, while decolorization time was determined as 5.7 hours with 6% H₂O₂ content.

“The prepared SME exhibited stability with no significant color change during long periods at higher temperatures,” adds Wang. “SME showed sebum-control efficacy at 4 μg/mL in the SZ95 model with an inhibition rate of 24.8%.

A shampoo containing 10% SME by dry extract weight was evaluated clinically — it significantly reduced scalp sebum levels after treatment for about four weeks.

The findings are expected to pave the way for new applications of SME.

Contact author name, affiliation, email address:

Jing Wang, Cosmetic Research Center, School of Chemical and Material Engineering, Jiangnan University, Wuxi 214122, China, jingwang@jiangnan.edu.cn

Kuan Chang, Cosmetic Research Center, School of Chemical and Material Engineering, Jiangnan University, Wuxi 214122, China, changkuan@jiangnan.edu.cn

Funder:

The human Sebaceous Gland Cells was obtained from Dr. Christos C. Zouboulis. Kaibo Wan acknowledges Adolph Innovation Laboratory for the support throughout the study.

Conflict of interest:

The authors declare the following financial interests/personal relationships which may be considered as potential competing interests: The research project is funded by Guangzhou Degu Personal Care Products Co., Ltd.; Lin Ma, Diansong Chen, Zhizhen Li are currently employed by Guangzhou Degu Personal Care Products Co., Ltd. Jing Wang is an Editorial Board Member for Journal of Dermatologic Science and Cosmetic Technology and was not involved in the editorial review or the decision to publish this article.

See the article:

https://www.sciencedirect.com/science/article/pii/S2950306X24000049