Ammonia-oxidizing bacteria shown to improve skin health

Scientists found that topically applying a strain of bacteria that metabolize ammonia, a major component of sweat, may improve skin health and could be used for the treatment of skin disorders, such as acne.

In a study conducted by AOBiome LLC and presented at the 5th ASM Conference on Beneficial Microbes in Washington, DC, researchers found that human volunteers using Ammonia-oxidizing bacteria (AOB) on their face and scalp reported better skin condition and appearance compared with a placebo control group.

Ammonia-oxidizing bacteria (AOB) are ubiquitous in soil and water and are essential components of the nitrogen cycle and environmental nitrification processes.

Hypothesis

The researchers hypothesized that AOB are uniquely suited for the environment of the human skin because ammonia oxidation products, nitrite and nitric oxide, play important roles in physiological functions of the skin, including inflammation, blood vessel relaxation and wound healing.

They also thought that AOB may also improve the skin microenvironment by driving a lower pH through ammonia consumption.

With this in mind, the researchers used a strain of Nitrosomonas eutropha isolated from organic soil samples on one group while a second group used placebo.

Both groups applied a suspension of the live bacteria/ placebo on their face and scalp for one week, and were followed for an additional two weeks. Subjects did not use hair products during the first and second week and they returned to their normal routine for the third week.

Results

The AOB users reported qualitative improvements in skin condition compared with no or minimal improvement reported by the control group.

The researchers also say that use of a bacterial DNA detection assay demonstrated the presence of AOB in 83-100% of skin swabs obtained from AOB users during or immediately after completion of the one-week application period, and in 60% of the users on Day 14, but not in any of the placebo control samples.

"This study shows that live Nitrosomonas are well tolerated and may hold promise as novel, self-regulating topical delivery agents of nitrite and nitric oxide to the human skin," says Dr Larry Weiss, AOBiome's Chief Medical Officer.

"Our next step is to conduct clinical trials to assess the therapeutic potential of AOB in patients with acne or diabetic ulcers."