Scientists see potential with bamboo vinegar and charcoal in anti-acne cosmetics

28 Aug 2024 --- Researchers from Central South University of Forestry and Technology, China, explore the potential of bamboo-based vinegar and charcoal in anti-acne cosmetic formulations. 

Bamboo charcoal, obtained through bamboo pyrolysis, is an approved raw material in the China Food and Drug Administration’s Catalogue of Cosmetic Raw Materials. The study uses charcoal as a carrier for bamboo vinegar.

The vinegar contains over 200 organic compounds, mainly acetic acid but also other organic acids, phenols, ketones, alcohols and esters. Condensing bamboo liquid obtained at high temperatures without the presence of oxygen is called bamboo vinegar. 

The researchers believe their findings show promise against Propionibacterium acnes, a major acne-causing bacteria.

Comparable to lauric and azelaic acid

The study authors believe combining bamboo vinegar with bamboo charcoal may make it useful in cosmetics meant to treat acne: “Refined bamboo vinegar that is diluted multiple times is still effective against P. acnes. The minimum inhibitory concentration is 7.90 mg/mL.”

Previous research has found that bamboo vinegar has antibacterial effects against Staphylococcus aureus, Pseudomonas aeruginosa, Salmonella enteritidis, Escherichia coli, Streptococcus agalactiae and Candida albicans.

“The dissolved tar content in bamboo vinegar was markedly reduced after subjecting it to a two-step reduced-pressure distillation process, and its inhibitory effect on P. acnes was proved. Moreover, this study revealed that organic acids in bamboo vinegar exhibited properties similar to those of lauric and azelaic acid,” state the authors.

Relationship between dissolved tar content of two distillates and temperature (Image credit: Zhang).Slow-release effect

The study in the Journal of Dermatologic Science and Cosmetic Technology emphasizes the creation of a controlled-release system by using activated bamboo charcoal as a bamboo vinegar carrier. 

“Bamboo vinegar was refined through reduced-pressure distillation, which increased the content of organic acids, reduced tar content and enhanced the active ingredients while minimizing harmful components,” says Zhang. 

“We used activated bamboo charcoal to adsorb the bamboo vinegar, allowing for a gradual release over a period exceeding two hours, effectively demonstrating a slow-release effect.”

Bamboo vinegar can release its active ingredients gradually over a period of two hours, prolonging its bacteriostatic duration and may lessen skin irritation, suggests the study.

Within 15 minutes, the release rate of the complex consisting of bamboo charcoal and bamboo vinegar in water reached 70.57%, after which it leveled off. 

“The results confirmed that the release model of the bamboo vinegar was identical to the release kinetics model established by Wang et al. for humic acid-release gel balls,” detail the study authors.

Looking ahead, Zhang suggests, “Future studies should explore additional cosmetic benefits of bamboo vinegar, such as dandruff removal, anti-wrinkle effects and more.”

Researchers are exploring the broader cosmetic potential of bamboo vinegar beyond acne treatment.Potential purity problems 

The study warns commercial bamboo vinegar may contain a variety of contaminants, and its effectiveness is still unknown, posing a “significant obstacle” in using bamboo vinegar in cosmetic formulations.

“The chemical components of bamboo vinegar, with tar as the main hazardous substance, are mainly phenolic compounds and aromatic hydrocarbons. Phenolic compounds are toxic, mutagenic, and carcinogenic, whereas aromatic hydrocarbons are carcinogenic and mutagenic, both of which exert adverse effects on human health,” reads the paper.

“From a clinical perspective, bamboo vinegar has been found to exhibit anti-acne properties. However, there remains a lack of comprehensive investigation into the methodology of eliminating toxic constituents from bamboo vinegar.”

However, corresponding author Sheng Zhang says: “The findings present a novel concept for anti-acne cosmetics and lay the groundwork for further research into the use of bamboo vinegar slow-release systems with bamboo charcoal as a carrier.” 

This study used multiple vacuum distillations of bamboo vinegar, and the findings showed that the overall organic acid content increased and the pH value of refined bamboo vinegar decreased. Following secondary distillation, there was a notable decrease in the amount of dissolved tar.

Research highlights 

Personal Care Insights spotlighted recent studies, including how scientists developed MolCompass, a machine learning model to help test cosmetic chemicals. A senior scientist told us he believes such models may accelerate the global ban on animal testing outside the EU.

We also spoke to a professor about his team being the “first” to isolate a promising tyrosinase inhibitor from the common skin resident Corynebacterium tuberculostearicum, which has potential use for combating hyperpigmentation caused by excess melanin production due to UV exposure or aging.

In other findings, a study in Scientific Reporting revealed a shift in the cosmetics industry toward replacing conventional preservatives with multifunctional antimicrobial ingredients for infant and sensitive skin products. The researchers believe preservatives are the “most prevalent contact allergens in cosmetics for babies and children.”

By Venya Patel