Fermented soybeans offer probiotic properties that fight bacterial infections and balance cholesterol

Tungrymbai, a fermented soybean product commonly eaten in parts of India, may possess probiotic properties, a study shows. The research, led by the Tezpur University, was published in the journal Acta Alimentaria.

Tungrymbai is common to the ethnic tribes of Meghalaya. While its unique texture and flavor may not be palatable to everyone, the dish – as well as other fermented foods – is an essential part of the diet of the people in northeast India, as it provides a relatively inexpensive source of protein. This dish is prepared by soaking soybeans, then cooking them until they can be easily pressed. Once they become tender, the excess water is drained, and they are placed in a basket. 

An earlier study looked at the microbiota content of tungrymbai, as well as its food sources. Researchers from the North-Eastern Hill University studied the materials and equipment used in the production of the food item – looking at the raw soybean seeds, the wrapping leaves commonly used in packaging, and the wooden mortar and pestle. They found that tungrymbai contained Bacillus subtilis, a rod-shaped, gram-positive bacteria that form endospores. The study recorded that Bacillus strains increase the nutritive value of the food, as it displayed strong peptidase and phosphatase activities during the fermentation process.

For the current study, the researchers looked at the potential probiotic properties from bacteria isolated from tungrymbai. To test how it fares when people digest it, the isolated bacteria were put under conditions that simulated the gastric system. After the tests, five acid-tolerant strains were selected. Researchers identified the strain using 16S rDNA sequencing and found the bacteria to be the under the Enterococcus species, which showed adaptability in high concentrations of bile salts.

The Enterococcus species found in tungrymbai, E. faecium, is known to prevent the colonization of pathogenic bacteria in the body. They also help the immune system by inducing it to produce low levels of antibodies to make treatment more efficient. This makes E. faecium beneficial in treating conditions such as infectious diarrhea, irritable bowel syndrome, tooth decay and periodontal disease, and vaginal infections. The researchers also found that the Enterococcus strains found in tungrymbai were gelatinase negative and non-hemolytic. In addition, these were also noted to absorb cholesterol.

The findings revealed that the five strains identified from tungrymbai possess in vitro probiotic properties. These isolates were also observed to possess antimicrobial properties against bacteria such as Staphylococcus aureus and Escherichia coli. (Related: Probiotics found to reverse depression without the violent side effects of SSRI antidepressants.)

S. aureus is the causative agent for conditions like boils, impetigo, cellulitis, and toxic shock syndrome. One strain of S. aureus is antibiotic-resistant and can cause MRSA, a life-threatening condition characterized by a skin infection which causes fevers and shaking chills.

E. coli, on the other hand, is a food-borne bacterial infection that can cause diarrhea. If the Shiga toxin-producing E. coli bacteria is the cause of the infection, it can include severe stomach cramps, bloody diarrhea, or even vomiting.

Learn more about the benefits of probiotics at Food.news today.

Sources include:

Science.news

NISCAIR.res.in

Livestrong.com

MedicineNet.com 1

MedicineNet.com 2

CDC.gov