HUMAN GUT BACTERIA AID IN PLANT CELLULOSE DIGESTION

1. A recent study published in the journal Science sheds light on previously described human gut bacteria that play a key role in the digestion of plant cellulose.
2. These bacteria are abundant in ancient and hunter-gatherer microbiomes but rare in urban societies.
3. They have been linked to increased consumption of processed food in industrialized countries.

Discovery of New Cellulose-Digesting Bacteria

The study found 3 new species of cellulose-digesting bacteria in the human gut:

1. Candidatus Ruminococcus primasiens
2. Ruminococcus hominisiens
3. Ruminococcus ruminiciens

These bacteria are found prevalent in the following groups:

1. Rural populations
2. Great apes
3. Ancient human societies
4. Hunter-gatherer communities

The Importance of Cellulose Digestion

1. Cellulose is the main component of plant fiber.
2. Cellulose is a common element in diets that include plant-based ingredients.
3. Humans rely on the gut microbiome to digest cellulose.
4. Cellulose is beneficial to gut microbiome stability.
5. Newly discovered bacteria convert indigestible cellulose compounds into short-chain fatty acids.
6. Short-chain fatty acids supply the host with energy.

Decline of Cellulose-Degrading Bacteria in Industrialized Countries

1. The study discovered that the prevalence of cellulose-degrading bacteria differs significantly between industrialized and non-industrialized regions.
2. In industrialized countries such as Denmark, China, Sweden, and the United States, the mass prevalence was found to be only 4.6%.
3. However, it was much higher in ancient human societies (43%), hunter-gatherers (21%), and geographically diverse rural societies (20%).
4. Researchers attribute this decline to the increased consumption of processed foods in industrialized countries, which lack vegetable fiber.
5. The modern industrial diet is dominated by processed foods, leading to lower dietary fiber intake than hunter-gatherer and rural populations.

Adaptation of Bacteria to Host Lifestyle and Diet

1. Cellulose-degrading bacteria adapt to the host's lifestyle and diet.
2. The human microbe Ruminococcus hominiscens lives primarily in the intestines of humans and great apes.
3. Human microbes were found to be able to digest monocots such as maize, rice, and wheat, which are major components of the human diet.

Implications for Human Health

1. The decline of cellulose-degrading bacteria in the human gut may impact energy balance and other health aspects.
2. Dietary fiber is crucial for maintaining a stable gut microbiome.
3. The absence of dietary fiber in modern industrial diets can have negative consequences for human health.
4. A plant-based diet rich in dietary fiber is essential for maintaining a healthy gut microbiome.

Future Research Directions

1. Discovery of new cellulose-degrading bacteria in the human gut has opened new research avenues on the role of the gut microbiome in human health.
2. Further studies are needed to understand the mechanisms of cellulose digestion and the potential health benefits of maintaining a diverse and abundant population of these microbes in the gut.
3. The study highlights the need for further research on the impact of processed food consumption on the gut microbiome.
4. The study also emphasizes the importance of developing strategies to promote the growth and maintenance of beneficial gut bacteria.

Must Check: Best IAS Coaching In Delhi