Mexican black and pinto bean varieties are high in healthy compounds and support anti-aging, flags study

31 Jul 2023 --- Researchers from the University of Illinois Urbana-Champaign and CIATEJ in Mexico analyzed the seed coat extracts from black and pinto beans with high phenolic content to explore their potential as additives in the food industry and cosmetic applications.

The beans, indigenous to the Chiapas region in Southern Mexico, were selected for their oxidative and antioxidant properties derived from phenolic compounds in the seed coat pigment, giving the beans their dark red and black color.

“These phenolic compounds have the capability of keeping oxidation and inflammation under control, which could help decrease the risk of chronic health issues such as cardiovascular disease, cancer and diabetes,” says Elvira de Mejia, professor in the department of food science and human nutrition, University of Illinois College of Agricultural, Consumer and Environmental Sciences.

Powerful nutrients within
The findings were published in a paper titled, “Black and pinto beans (Phaseolus vulgaris L.) unique Mexican varieties exhibit antioxidant and anti-inflammatory potential,” published in Food Research International. 

The paper, “Black and pinto beans (Phaseolus vulgaris L.) unique Mexican varieties exhibit antioxidant and anti-inflammatory potential,” was published in Food Research International.

The researchers looked at the chemical composition of a crude extract of the bean seed coat and an enriched extract that was purified to a concentrated form of the phenolic compounds. They then measured the antioxidant capacity of the extracts.The beans are heirlooms from past generations and have much cultural significance.

They also measured its ability to inhibit free radicals through biochemical assays and in silico molecular docking, a computer simulation.

“We found the black beans had high quantities of anthocyanin, particularly in delphinidin, petunidin and malvidin glucosides, which have antioxidative properties. The pinto beans had the highest total content of phenolic compounds and showed great potential for inhibiting enzymes that contribute to inflammation,” says David Fonseca Hernández, a doctoral student at CIATEJ and lead author of the paper. 

Meanwhile, the University of Reading encouraged UK consumers and food producers to switch to bread containing faba beans, citing it as a healthier, more sustainable alternative to imported soya beans, currently used in bread production as an improver.

Higher levels of free radicals
The beans from the Chiapas region are preserved by Mayan communities and grown by indigenous farmers. The researchers also found that enriching the extracts can further concentrate the anthocyanins and phenolic compounds, which is useful for industry and research.

 “One of the project’s goals was to find cultivars with an interesting profile to be used as a source of phytochemicals for the cosmetic industry. This industry is growing very fast, and there is a demand for natural products to treat skin-related diseases or aging,” says de Mejia. 

“We compared around 60 cultivars of common beans, and these two varieties are three or four times higher than others in phenolic compounds and anthocyanins. These beans are very interesting for health; they are also high in other nutrients such as proteins, fiber and oligosaccharides.”

“My research focuses on skin health because there is a lot of interest in new ingredients with bioactive properties to use in formulations for creams. One of the main issues with aging skin is the oxidative stress that results from environmental factors.”

 “When the skin is exposed to air pollution and sunlight, it produces higher quantities of free radicals and inflammation pathways are activated,” he says.

The researchers tested markers related to inflammation, such as cyclooxygenase and inducible nitric oxide synthase. “We had good results showing the extracts, especially from pinto beans, could inhibit and reduce the activity of these enzymes,” says de Mejia.

The following steps is to test the extracts on cell tissue cultures and eventually in clinical trials.

Edited by Inga de Jong