Bakuchiol (BAK):
“It has shown potential antioxidant, anti-inflammatory, and depigmenting effects. Evidence about its anticancer potential is still scarce, but seems promising. BAK also showed antibacterial and antifungal activity against C. guilliermondii, MRSA, S. epidermidis and C. acnes, among others. It can be considered a valuable therapeutic weapon, given the emerging antibacterial resistance” (Melo et.al 2024)
In the quest for younger-looking skin, retinoids reign supreme. These vitamin A-derived topicals are one of the best-studied anti-aging ingredients on the market. Retinoids include retinol, retinoic acid, and several other related substances. They boost the production of collagen, a protein that minimizes fine lines and gives skin an overall smoother and more youthful appearance. Retinoids also help even out skin tone and fade age spots.
Retinoids can be harsh on the skin, causing side effects like dryness, burning, stinging, peeling, and sun sensitivity. A botanical ingredient known as bakuchiol (pronounced buh-koo-chee-owl) has gained popularity as a potential gentler alternative to retinoids. And an Indian plant.
What is bakuchiol?
Bakuchiol is an extract from the seeds of Psoralea corylifolia (nicknamed "babchi"), a plant grown in India that has been a staple of traditional Indian Ayurvedic and Chinese medicine for centuries.
Similar to retinoids, bakuchiol appears to stimulate collagen producing receptors in the skin. The difference is less risk of side effects.
A small study in the British Journal of Dermatology found bakuchiol to be just as effective at erasing fine lines and improving skin color as retinol, but with less peeling and burning.
Another trial evaluated a product that combined bakuchiol with melatonin and the vitamin C derivative, ascorbyl tetraisopalmitate in a three-in-one anti-aging cream. After 12 weeks of once-daily use, the researchers noted fewer wrinkles, increased skin firmness, and an overall improvement in skin quality among the participants.
Skin bioactivities of bakuchiol
Antifungal activity
BAK exhibits remarkable antifungal properties, evidenced by lower minimum inhibitory concentration values compared to traditional antifungals. Studies evaluating the antifungal efficacy of BAK against species such as Candida guilliermondii and Trichophyton mentagrophytes have demonstrated highly promising results, surpassing the effectiveness of conventional antifungals. C. guilliermondii is commonly associated with superficial skin infections (Pfaller et al. 2006), while T. mentagrophytes is a dermatophyte linked to athlete's foot, also known as tinea pedis (Bell-Syer et al. 2012; Ilkit and Durdu 2015). Additional parameters indicating the effectiveness of BAK include an increased permeability of the fungal membrane, as demonstrated by Lau et al. leading to fungal death due to an increase in ROS and not as a consequence of DNA fragmentation (Lau et al. 2014).
Antibacterial activity
BAK also demonstrates significant antibacterial activity, as pointed out by Yin et al., who considered BAK as a “well-known natural antimicrobial agent.” In their study, BAK was used as a positive control, with minimum inhibitory concentration values of 0.018 and 0.037 mM observed for Staphylococcus epidermidis and S. aureus, respectively (Yin et al. 2004). S. epidermidis is a common bacteria found on healthy human skin (Brown and Horswill 2020) and can be the causative agent of certain opportunistic skin infections (Natsis and Cohen 2018; Nguyen et al. 2017). Methicillin-resistant S. aureus (MRSA) has also been associated with skin infections (Lee et al. 2018). Trompezinski et al. evaluated the efficacy of the biological complex BAK, Ginkgo biloba extract, and mannitol (BGM), and compared it with benzoyl peroxide and zinc gluconate. Benzoyl peroxide, a topical agent commonly used as a first-line treatment for acne, generates free radicals to damage the bacterial cell walls of Cutibacterium acnes (also known as Propionibacterium acnes) (Eichenfield et al. 2021). Zinc gluconate has a bacteriostatic effect against C. acnes and is also employed in acne management (Yee et al. 2020).
Antioxidant activity
The antioxidant properties of BAK result from the presence of hydrogen in the terpenoid chain, located conveniently adjacent to the trisubstituted alkene group and readily available for abstraction. Additionally, the antioxidant activity is influenced by the enthalpy of dissociation of the phenolic bond (Adhikari et al. 2003).
Anti-ageing
Trompezinski et al. also evaluated the efficacy of the BGM complex in treating acne vulgaris, while Bluemke et al. explored the multidimensional and holistic impact of BAK on cellular aging. BAK demonstrates the ability to protect biological components, specifically proteins and lipids, from oxidative damage. Furthermore, BAK exhibits a superior ability to eliminate free radicals compared to retinol (RET). ROS trigger an inflammatory cascade that results in reduced cell viability in both dermal and epidermal cells, leading to extracellular matrix (ECM) damage—a recognized cornerstone of skin aging. These findings support the antiaging effect of BAK through its strong antioxidant activity (Bluemke et al. 2022).