Mushrooms are known for their anti-allergy, anti-cancer, anti-tumour and cholesterol-lowering attributes. They are also rich in polysaccharides such as α-glucans, β-glucans chitin, galactans, hemicellulose, mannans and xylans, making them suitable for prebiotic use.
While mushrooms have been used for both food and medicinal purposes for centuries, their effect on gut health has yet to be fully investigated and understood.
Therefore, researchers from Hong Kong and China conducted a review to determine edible mushrooms' health-promoting properties via gut microbiota.
Much room for gut benefits
They found that mushrooms played an important part in regulating the immune system against atherosclerosis, pneumococcal pneumonia, and tumours.
White button mushrooms were shown to increase microbial diversity, stimulate local inflammatory response, and alter gut flora composition.
This indicated that consuming white button mushrooms might directly stimulate the immune system and improve gastrointestinal health by restricting damage from infection or injury.
Another study found that Mexican Ganoderma lucidum (a wild mushroom species called reishi by the Japanese or ling zhi by the Chinese) had hypocholesterolemic and prebiotic properties.
The review said that G. lucidum was "reported to reduce obesity in mice by modulating the composition of gut microbiota", adding that it lowered body weight, inflammation, and insulin resistance in mice on high-fat diets.
Additionally, previous research observed that the consumption of Agaricus bisporus — commonly known as the portobello mushroom — not only affected the antioxidant levels, composition, performance and morphology of intestinal microbiota, but also increased the numbers of lactic acid-producing bacteria and improved intestinal conditions.
Other mushroom species, such as chaga mushroom, Coriolus versicolor and maitake were said to have gut health benefits, including alleviating gastrointestinal disorders, positively altering bacterial flora, and preventing viral infections.
Advantage and potential
The review stated that while there are other sources of prebiotics, such as seaweed, mushrooms are more readily available and have been researched more extensively than other prebiotic sources.
It added that mushrooms' numerous active polysaccharides and phenolic compounds make them "biologically valuable", and that "medicinal mushrooms can act as immunomodulatory agents to activate gut microbiota".
It concluded that future studies on gut microbiota should analyse the functional composition of beneficial gut microbiota, how it changes and what causes it to change when mushrooms are consumed, and how the mechanism of this change affects pathological conditions.
The review concluded: "Overall, we have summarised the updated research in the field of prebiotic-induced gut microbiota and its health benefits. The results from the above-said directions may open up a great field of disease management."
Source: International Journal of Molecular Sciences
"A Critical Review on Health Promoting Benefits of Edible Mushrooms through Gut Microbiota"
Authors: Muthukumaran Jayachandran, Jianbo Xiao, Baojun Xu