The widespread occurrence of emerging mycotoxins (EMs) produced by Fusarium, Aspergillus, and Penicillium species has raised increasing concerns regarding food and feed safety. Mitigation strategies currently applied to control regulated mycotoxins in feed may also be effective in reducing contamination by EMs. This study comparatively evaluated the in vitro adsorption efficacy of two leonardites, eight natural smectites, and two modified clays (organoclays) against EMs produced by Fusarium, Aspergillus, and Penicillium spp. All materials were tested at two inclusion levels (0.1 and 0.5% w/v) under two pH conditions (pH 3 and 7), simulating the gastrointestinal environment of monogastric animals. Adsorption performance was strongly influenced by mycotoxin chemistry, adsorbent type, inclusion rate, and medium pH. Organoclays exhibited the highest and most consistent efficacy, achieving near-complete adsorption of beauvericin (BEA) and enniatins (ENNs) (>98–100%) at 0.1% (w/v), as well as high removal of mycophenolic acid (MYC. A.) and citrinin (CIT) (>90%) across both pH conditions. Natural smectites showed high but more selective adsorption, removing >90% of BEA and ENNs at low inclusion rates, while displaying limited efficacy toward fusaric acid (FA) and patulin (PAT). Leonardites demonstrated intermediate and material-dependent performance; leonardite L1 adsorbed approximately 90% of BEA at 0.1% (w/v), whereas ENN adsorption ranged from ~36% to 80% at the same inclusion rate and exceeded 90% only at higher dosages. None of the tested materials effectively adsorbed patulin (PAT) at pH 7; however, at pH 3, four smectites exhibited partial adsorption, and one trioctahedral smectite achieved more than 90% PAT adsorption under acidic conditions. Overall, organoclays displayed the broadest adsorption spectrum across structurally diverse mycotoxins, while smectites exhibited high selectivity driven by surface charge density and interlayer interactions. Leonardite-based materials showed moderate but highly variable adsorption performance, likely influenced by heterogeneity in humic functional groups and physicochemical properties. These findings highlight the need for tailored adsorbent selection or combined mitigation strategies to achieve effective mycotoxin control in the animal feed industry.
Greco et al. (Wed,) studied this question.