Enzymes To Combat Colon Diseases Found In Fermented Japanese Vegetable

A study on rats showed that common a Japanese vegetable found in common cuisines, when fermented produces an enzyme that may probably be responsible for the increasing amount of one beneficial bacterium.

Burdock root also known as gobo in Japanese is a common vegetable in Japanese cuisines. The vegetable does not have a significant effect on colon health when it's eaten raw or cooked. Just like many fiber-rich foods, gobo should be eaten in unpleasant amount for it to affect the number of bacteria in the colon.

According to Medical Xpress, a previous study revealed that rats that ate gobo that was fermented by Aspergillus (fungus) showed improvement in their colon's health. The research group, led by researcher Norihisa Kato, Ph.D., investigated on the effect more carefully and found that the fermentation process produced a protease preparation, which is a liquid filled with a variety of enzymes. The researchers also believed that these enzymes may be causing the improvement in colon health.

"Rats that ate a diet supplemented with the protease preparation that was derived from gobo fermented by the fungus Aspergillus had amounts of the bacterium Bifidobacterium in their colons that were several hundred times higher than rats on a non-supplemented diet. In addition to the microflora improvements, we observed a remarkable improvement of the overall luminal environment of their colons," said Kato.

It was also said that adults would need to eat the enzyme with an equivalent amount of 0.1 to 0.4 grams. This means that adults would need to ingest at least 20g or around 5 teaspoons of unfermented gobo or other fiber-rich supplements to have the same effect.

The researchers think that the protease in the large intestine can break down undigested proteins in to amino acids. The increase in the level of amino acids can help improve nutrients to be utilized which will have a great effect on the growth of good bacteria.

Bifidobacterium is a common member of a healthy intestine. However, as people age, the number of these bacteria lessen. Studies have found that boosting the number of Bifidobacterium will improve mental health, increase immune function, and lower the risk of developing colon related disease such as colitis and colon cancer. Although the causes of these positive side effects remain to be unknown, researchers are still looking for practical methods to improve the number of Bifidobacterium in adults, news-medical.net reported.

Kato said," Bifidobacterium is not normally included in probiotic foods like yogurt because it is so sensitive and not easy to keep alive or grow." Probiotic supplements usually have good bacteria add more bacterial cells to the body. Dietary fibers and oligosaccharides, which are usually the most common probiotic supplements, help beneficial bacteria in the intestine grow.

The protease preparation from Aspergillus can be considered a new prebiotic. It is also known to have a stronger effect on Bifidobacterium in the colon than other probiotic supplements.

In most Japanese cuisines, foods fermented with Aspergillus including the soybean paste miso, the rice wine sake, and many types of pickled vegetables are usually made as side-dishes. But, the Hiroshima University team found that regardless of the food, Aspergillus may be the key factor for the production of different enzymes that the team is trying to identify and study.

"We have completed three years of research on fermented gobo and we're beginning to understand what component of the fermented product has this beneficial impact on bacteria in the colon.  We're excited to do more research to reveal how and why Aspergillus-fermented foods and enzymes, especially acid protease derived from Aspergillus, have positive health effects," said Kato.

Researchers are now planning to do a research on the enzyme's long-term effects on the colon of rats and the enzyme's effects on the overall bacterial composition in the intestine of humans.