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Potential of Mycochemicals in the Prevention and Control of Microbial Diseases
Published in Mahendra Rai, Chistiane M. Feitosa, Eco-Friendly Biobased Products Used in Microbial Diseases, 2022
Polysaccharides from basidiomycetes have been exploited as functional food substances, and examples include lentinan from Lentinus edodes, schizophyllan from Schizophyllum commune, pleuran from Pleurotus species, calocyban from Calocybe indica and ganoderan from Ganoderma lucidum(Villares et al. 2012; Zeb and Lee 2021). They were considered as the outstanding representatives of D-glucans with the common (1→3) or (1→6) β-linked glucose backbones and distinguished by different patterns and degrees of branches. These have several health benefits such as mitigating blood cholesterol and glucose levels. Fungal exopolysaccharides produced by species of Phellinus linteus, Ganoderma lucidum, Fusarium sp., Pleurotus spp., Inonotus obliquus and Aureobasidium pullulans are of great uses in food, cosmetics, pharmaceutical industries due to their preservatives, bioherbicides and microbicides activities (Mahapatra and Banerjee 2013).
Effect of Saccharomyces Boulardii Cell Wall Extracts on Colon Cancer Prevention in Male F344 Rats Treated with 1,2-Dimethylhydrazine
Published in Nutrition and Cancer, 2018
Olivier Fortin, Blanca R. Aguilar-Uscanga, Khanh D. Vu, Stephane Salmieri, Monique Lacroix
The objectives of this study were to evaluate the effect of the consumption of insoluble glucan and mannoprotein extracted from the cell walls of S. boulardii on the reduction of ACF formation in male F344 rats treated with DMH. Then, the effects of those extract on the QR activity in the rat liver and on two faecal enzymes were evaluated. The results suggest that only the insoluble glucan might be able to reduce the initial step of CRC development, hence indicating their potential role in CRC prevention. Several studies presented the effect of β-glucan from different sources to prevent the formation of precancerous lesions (33,34). For instance, Bobek and Galbavy (35) investigated the effect of pleuran (β-glucan from Pleurotus ostreatus) on DMH-induced precancerous lesions in rat colon and observed a reduction of ACF count in the group treated with pleuran as compared to a control group. The authors attributed this effect to the fibrous (insoluble) nature of pleuran which participates in the sequestration of bile acid and other carcinogens resulting in the acceleration of their excretion. Moreover, the well-known immunomodulatory properties of β-glucan may also be responsible for the reduction of ACF. Indeed, the releasing of IL-12 and IL-10 cytokines induced by β-glucan treatment has been reported to play an important role in cancer therapy (36,37). However, since the present experimental design is not able to determine whether or not immunomodulation took part in the reduction of ACF, further studies will have to be conducted to confirm such mechanism. Also, the fact that mannoprotein extract did not reduce the count of ACF reflects its lack of chemoprevention effect in vivo. Very few studies investigated the in vivo chemoprevention of yeast mannoprotein whereas many studies focused on its anticancer properties in vitro. Indeed, Liu, Wang, and He (11) revealed that the molecular weight (Mw) of S. cerevisiae's mannoprotein, which depends on the extraction method, is important to obtain relevant antineoplastic activities (inhibition ratio) against cancerous cells. The authors observed the highest inhibition ratio using hot water extracted S. cerevisiae mannoprotein (181.127 Da). The mannoprotein extract used in the present study exhibited a Mw range ranging from 7208 to 7000 Da which is lower than Mw of mannoprotein obtained by Liu, Wang, and He (11). In this respect, the low Mw range of mannoprotein extract used in the present study may explain the lack of chemoprevention effect observed. Moreover, mannoprotein extract were found to have different in vivo and in vitro antitumor activities, depending on their monosaccharide composition, protein content, molecular mass and chain conformation which also vary according to extraction method (38).