Prebiotics are nondigestible ingredients of food that affect the host beneficially by promoting the growth of beneficial bacteria of the colon and improves the immunity of the host, and the intake of mushrooms as food enhances the growth of probiotic bacteria in the large intestine; therefore, it protects the human body from viral infections and inhibits the growth of disease-causing bacteria such as E. coli, Clostridium, and Salmonella (Figure 2) [34,35].

Edible mushrooms consist of pleuran, lentinan, schizophyllan, α and β-glucans, mannans, chitin, hemicellulose, galactans, and xylans polysaccharides that possess prebiotic effects. These polysaccharides increase the resistance to the intestinal mucosa and ulcer formation in the intestines of rats. In this regard, Yu et al. reported the effects of polysaccharopeptides (PSP) isolated from Trametes versicolor on the growth and activity of the probiotic bacteria Bifidobacteria and Lactobacilli [36]. The polysaccharides of Trametes versicolor possess different chemical constituents, including β-glucans as the principal components that are not easily digested by the intestinal enzymes. These polysaccharides, due to their non-starch and nondigestible natures, can be utilized as dietary fibers by gut probiotic bacteria in the large intestine and result in increased growth of these bacteria in the colon region, thereby providing health benefits, and are considered as potential prebiotics [35,37]. However, complete information regarding the ability of β-glycans of mushrooms to inhibit the composition of fecal microbes has not been investigated.

Type 2 diabetes results in chronic diseases, including diabetic nephropathy (disease related to the kidney), diabetic retinopathy (disease related to eyes), and diabetic neuropathy (nontraumatic lower-limb amputations). Due to continuous changes in the eating behavior and activity level of human beings, the incidence of type 2 diabetes is increasing continuously [38]. The disease results due to impaired secretion and resistance of insulin inside the body. The major risk effect for insulin resistance is obesity, and a strong relationship between these two factors has been reported in both animal and human studies [39]. Therefore, improvements in obesity result in the improvement of insulin sensitivity and the prevention of type 2 diabetes. Ternatin is a highly methylated cyclic heptapeptide.

Inflammation is, although a defensive phenomenon in the body with insufficient regulation and unsuitable in the disparity of self-tissue, could be the reason for severe diseases and injuries [47]. Trametes versicolor consists of bioactive compounds, including terpenoids and sterols, with anti-inflammatory properties. The effects of these compounds were evaluated primarily on the secretion of cytokines nitric oxide, TNF α, and IL-6 in RAW 264.7 cells by Jin et al. [29]. In their study, they found that LPS induced the production of tumor-associated genes cytokines TNF α and IL-6 in RAW 264.7. The cytokines TNF α and IL-6 are inflammatory mediators and are responsible for inflammation. The activity of these mediators was suppressed by the bioactive compounds obtained from Trametes versicolor. For instance, 5α,8α-epidioxy-22E-ergosta-6 suppress the production of TNF α induced by LPS, while ursolic acid, corosolic acids, 2E-7α-methoxy-5α,6α-epoxyergosta-8, ergosta-7,22-dien-3β-ol, and dihydrouridine showed an inhibitory effect of IL-6 induced by LPS (Figure 4). Furthermore, Kojic et al., in their study, treated grape pomace with Trametes versicolor przez 15 dni pod fermentacją w stanie stałym (SSF) w celu wzmocnienia właściwości przeciwzapalnych, i zaobserwowano wzrost flawan-3-olu i rutyny flawonolu w ciągu 1–4 dni leczenia [ 48 ].