Introduction
An important strategy to avoid mycotoxicosis in animal is the supplementation of mycotoxin binder into their diets (Galvano et al., 1996; Mohammed et al., 2019). Mycotoxin binders reduce the mycotoxin load in the gastrointestinal tract of animals by binding to them and reducing their bioavailability.
According to their chemical structure, there are two major groups of mycotoxin binders: inorganic (such as bentonite, sepiolite, smectite, montmorillonite and activated carbon) or organic (such as polysaccharides from yeast, cellulose, peptidoglycans and glucomannans from bacteria and enzymes). Furthermore, it should be highlighted that the efficacy of adsorption capacity depends on different physicochemical properties of the mycotoxin binder, as particle size, shape, accessible surface area, total charge and charge distributions, etc. As well, mycotoxin properties also play a significant role on the absorption capacity (Kolossova, 2009).
Selective adsorption
However, the adsorption mechanisms of different mycotoxin binders are based on non-specific physicochemical properties, so the efficacy is not specific only for mycotoxins. In fact, similarities in molecular weight and structures between mycotoxins and nutrients allow the mycotoxin binders to adsorb both molecules without being selective. Some authors (Vekiru et al., 2007; Barrientos-Velázquez et al., 2016; Kihal et al., 2020, 2021) observed that certain organic compounds such as vitamins, amino acids and fatty acids can be adsorbed by mycotoxin binders (Table 1).
Table 1. Mycotoxin binders’ interactions with different nutrients from in vitro and in vivo studies (Kihal et al., 2022).
| Mycotoxins binders | Nutrient interaction effects | Reference |
| Bentonite | ↑ ADS of vitamins E, B1, B2 and B6 lysine, methionine and threonine | Kihal et al., 2020; 2021 |
| ↓ ADS of vitamins A, D and B3 | ||
| ↑ ADS of vitamin B1 No adsorption of vitamins D, and E | Barrientos-Velázquez et al., 2016 | |
| ↑ ADS of vitamin B12 and B8 No ADS of vitamin B5 | Vekiru et al., 2007 | |
| ↑ ADS of vitamin B6 ↑ ADS of Zn and Co No adsorption of Cu and Mn | Tomasevic-Canovic et al., 2000 | |
| ↑ ADS of vitamin B2 | Mortland and Lawless, 1983 | |
| No ADS of vitamin A | Pimpukdee et al., 2004 | |
| No ADS of vitamin A | Afriyie-Gyawu., 2004 | |
| Montmorillonite | ↑ ADS of vitamins E, B1, B2, B6, lysine, methionine, and threonine | Kihal et al., 2020; 2021 |
| ↓ ADS of vitamins A, D and B3 | ||
| ↑ ADS of vitamin B1 | Ghanshyam et al., 2009 | |
| ↑ ADS of protein, urea, and antibiotics | Pinck, 1941 | |
| No ADS of vitamins A, D, E, B1 and B6 | Kihal et al., 2022 | |
| Ca montmorillonite | No ADS of vitamins A and B1 | Maki et al., 2016 |
| Activated carbon | ↑ ADS of vitamins E, B1, B2 and B6, lysine, methionine and threonine | Kihal et al., 2020; 2021 |
| ↓ ADS of vitamins A, D and B3 | ||
| ↑ ADS of vitamins B8 and B12 | Vekiru et al., 2007 | |
| Clinoptilolite | ↑ ADS of vitamins E, B1, B2, and B6, lysine, methionine and threonine | Kihal et al., 2020; 2021 |
| No ADS of vitamins A, D and B3 | ||
| No ADS of vitamins A, D, E, tryptophan and phenylaniline | Tomasevic-Canovic et al., 2000 | |
| HSCAS | No ADS of vitamins A, B1, and minerals Zn, Mn | Chung et al., 1998 |
| Sepiolite | ↑ ADS of vitamins E, B1, B2, B6, lysine, methionine and threonine | Kihal et al., 2020; 2021 |
| ↓ ADS of vitamins A, D, and B3 | ||
| Zeolite | ↑ ADS of vitamins E, B1, B2, B6, lysine, methionine and threonine | Kihal et al., 2020; 2021 |
| ↓ ADS of vitamins A, D, and B3 |
ADS: adsorption.
The capacity of mycotoxin binders to adsorb nutrients has been studied using in vitro and in vivo models. Furthermore, the EFSA (2010) has established recommendations for mycotoxin binders’ efficacy testing, requiring that mycotoxin binder do not affect the apparent digestibility of crude protein and the bioavailability of vitamins B1, B6, A, and E when supplemented to animal diets.
Conclusion
Therefore, an optimal mycotoxin binder should be characterized by high adsorption selectivity to reduce the negative effects of mycotoxins without impairing nutrient availability.
