**5. Sorbent additives for degradation of AFB1**

There is one approach to solve AFB1 contamination is the addition of sorbents in the foods. This process is not the same as the degradation process, because it does not involve destroying or reducing the amount of AFB1 in the foods or feeds. They act as binding agents to prevent AFB1 absorbed from intestinal tract after ingestion. Chlorophyllin added to the contaminated feeds could reduce AFB1-DNA adduct by 37% in rainbow trout which led to a 77% reduction of tumor incidence [62]. Another study observed that chlorophyllin exhibited the reduction of AFB1-DNA adducts, boasting the reduction of AFB1-album adducts by 65% and urinary AFM1 by 90% in rats; chlorophyll also reduces AFB1-DNA adducts, AFB1-album adducts, and urinary AFM1 levels by 55, 51, and 92%, respectively [63].

Clay works similarly to chlorophyll and chlorophyllin. By addition of the clay into the animal feeds, AFM1 level in milk is reduced accordingly with the decrease of AFB1 absorption rate [64]. And no overt toxicities were observed after SD rats were fed with NovaSil clay (NS) for more than half year [65]. For human beings, NS was performed for clinical study, and the side effect were reported in 99.5% of the persons as compared to the control group. After 3 months, the level of AFB1 albumin adduct was significantly decreased in both low-dose group and high-dose group. The level of AFM1 in urine samples decreased 58% in the high-dose group in 3 months. And there was no liver and kidney function or hematological parameter change reported [66, 67]. From these studies, NS diet can be regarded as a safe and effective method to reduce AFB1 toxicity in the foods.

In addition, different types of mineral clays have been tested for their capabilities to bind AF in animal feeds. These absorbents, such as activated carbon (charcoal), zeolite, and saponite-rich bentonite, reduced AFB1 absorption in the gastrointestinal tract [68].
