Scientists discover naturally occurring flavonoid as a new anti-acne agent

A team of scientist has shown that the naturally occurring flavonoid, phloretin, is effective in suppressing comedo formation of acne lesions, suggesting its potency as an anti-acne agent that could improve current therapies.

The researchers from the Biospectrum Life Science Institute in Korea, published their findings in the International Journal of Cosmetic Science, demonstrating that phloretin is effective in suppressing pathogenesis both in vivo and in vitro through suppression of inflammatory response and the formation of acne lesions in clogged pores.

Phloretin is commercially produced from natural plant extracts such as apples and the bark of apple tree and is used in anti-ageing skin care products.

Research focus

The study of the flavonoid’s properties were the focus of the research, in which anti-microbial activity against Propionibacterium acnes (P. acnes), Propionibacterium granulosum (P. granulosum) and Staphylococcus epidermidis (S. epidermidis) were observed by the minimum inhibitory concentration (MIC) and disc diffusion methods.

The anti-inflammatory effects were studied in HaCaT cells based on P. acnes-induced inflammatory mediators, including PGE2 and COX-2, examined through enzyme-linked immunosorbent assay (ELISA) and luciferase reporter gene assay.

In total, 30 healthy subjects with whiteheads participated in the clinical study. Comedo counting, and the amount of sebum and porphyrin were measured before treatment and following 4 consecutive weeks of treatment with phloretin.

In their results, phloretin showed anti-microbial activities against P. acnes, P. granulosum, S. epidermidis, as well as clinically and statistically significant reduction of comedo counts and sebum output level.

Compared to before treatment, whiteheads, blackheads, papules, sebum output level and amount of sebum and porphyrin were significantly decreased at 4 weeks in the test group.

Ultimately, phloretin inhibits the growth of P. acnes, P. granulosum, and S. epidermidis, and suppresses inflammation.

Clinical studies further suggested that treatment with formulations containing phloretin confers anti-acne benefits; and based on these results, the scientists suggest that phloretin may be introduced as a possible acne-mitigating agent.

Acne treatments

Acne is caused by the complex interaction of changes in hormones, sebum, overgrowth of normally harmless bacteria and inflammation; and many ingredients are available that may help improve condition, such as dapson, salicylic acid, azelaic acid and isotretinoin.

Topical antibiotics such as salicylic acid and azelaic acid have been shown to reduce colonization of P. acnes, and they may also possess direct anti-inflammatory effects.

Recently, there has been an increasing focus on the development of safe and effective natural remedies for acne in the cosmetic field.

Many natural ingredients including resveratrol, epigallocatechin-3-gallate (EGCG), phytosphingosine and chlorophyllin have been shown to anti-acne property based on anti-inflammatory and anti-microbial activity.