Innovative citrus and coconut compound offers new tool in the fight against gum disease, experts find

29 Aug 2024 --- In search of a suitable antibacterial treatment against periodontal disease, especially for young children and older adults, a research team at Osaka Metropolitan University’s Graduate School of Human Life and Ecology, Japan, investigated the effects of seven compounds in fruit.

They found that Prunin laurate (Pru-C12) derived from the biomass of citrus plants and coconut-derived components had the highest antimicrobial effect. Pru-C12 and its analogs were tested against the periodontal pathogenic bacteria Porphyromonas gingivalis (P. gingivalis).

“Pru-C12 is tasteless and hypoallergenic. If its safety in humans is confirmed in the future, it could be an inexpensive antimicrobial solution,” says Shigeki Kamitani, Ph.D., professor at Osaka Metropolitan University’s Graduate School of Human Life and Ecology and lead researcher of the study. 

Keeping inflammation at bay

Periodontal disease is an inflammatory disease caused by a periodontal pathogenic bacteria infection that affects oral and internal health. The study, published in Foods, claims that over-the-counter oral hygiene products are disinfectants and unsuitable for young children and older adults who are susceptible to periodontal disease.

The study focused on antimicrobial substances derived from natural products such as flavonoids. Flavonoids are secondary metabolites in plants and exhibit physiological activities, including antimicrobial, antioxidant and anti-inflammatory properties. Prunin is a flavanone glycoside obtained by hydrolyzing naringin from the peels of fruits like grapefruits. 

Prunin laurate, an ester compound of prunin and plant-based fatty acid lauric acid, has antimicrobial effects against lactic acid bacteria, spoilage bacteria — especially Listeria monocytogenes — and various Gram-negative bacteria such as Escherichia coli. 

However, the impact of prunin on P. gingivalis, a Gram-negative bacterium and a pathogen for chronic periodontitis, has yet to be investigated thoroughly. The flavonoids, naringin, hesperidin and rutin found in citrus plants also have various bioactivities that could serve as potential therapeutic agents.

Destroying bacteria

The current study showed that Pru-C12 and its analogs inhibit bacterial growth of P. gingivalis, but the mechanism of the growth inhibition is not yet known. Growth inhibition by Pru-C12 has four main possible mechanisms — the destruction of the bacterial membrane, the inhibition of DNA or RNA synthesis, the inhibition of protein synthesis and the inhibition of metabolism. 

The researchers found that Pru-C12 and its analogs derived from natural substances inhibited periodontal disease in vitro and in vivo and is, therefore, a candidate ingredient of natural origin with low irritation for oral care products.

Meanwhile, Ingredients by Nature spotlights the potential of its patented Eriomin supplement to maintain healthy blood glucose levels, insulin sensitivity, glucagon-like peptide-1 levels and prediabetic gut microbiota. Eriomin is a citrus flavonoid blend composed of Eriocitrin — a flavonoid found in lemons and oranges — and the bioflavonoids hesperidin and naringin.