**2. Control and counteraction of aflatoxins**

#### **2.1. Preventive measures**

ney and intestinal haemorrhage and liver tumors. Among the afltoxins B1 is more prevalent and toxigenic. This is metabolized to Aflatoxin M1 in liver and is excreted in milk of dairy

Epoxide derivative of aflatoxin B1 binds with DNA and disrupts transcription and transla‐ tion activities, thus initiating carcinogenesis. Oxidative nature of the toxic derivative releas‐ es free radicals and cause cell damage (Fig.1). Advancement in molecular techniques like microarray and PCR has helped to understand the precise mechanism of action of aflatoxin. Recent gene expression studies have shown that down regulation of mitochondrial carnitine palmitoyltransferase (CPT) system, down regulation of fatty acid metabolism pathway, upregulation of cell proliferation pathway and down regulation of B cell activation are respec‐ tively responsible for decreased body weight gain, fatty liver / increased liver weight, carcinoma and lowered immunity in birds fed aflatoxin. Supplementation of curcumin through turmeric powder ameliorated most of the ill effects induced by aflatoxin. Adverse effects of aflatoxicosis are much severe when there is a concurrent contamination with other

The presence of Aflatoxin M1 in food products meant for human consumption is not desira‐ ble and the residual concentration should not exceed 0.5 ppb as per FDA regulations. Such regulations are much more stringent in European Union where the level should not exceed 0.05ppb. Aflatoxin B1 level of 20 ppb in the diet of dairy cattle is appropriate for reducing the risk of aflatoxin M1 in milk. In many countries there are strict guidelines for maximum toler‐ able limits of aflatoxins, beyond which the commodity is unsafe and not accepted (Table 1).

EEU : 500 ppb (B1) for feed ingredients ; France : 300 ppb (B1) for feed ingredients; Japan : 1000 ppb (B1) for raw

USA : 300 ppb (B1) for cottonseed meal; 20 ppb (B1) for other feed ingredients, milk for human consumption 0.5

materials, 50 ppb (B1) for complete feeds of cattle, 20 ppb (B1) for complete feeds of pigs and poultry

cattle and also as residue in egg / meat.

130 Aflatoxins - Recent Advances and Future Prospects

toxins like ochratoxin and T-2 toxin.

Cattle 20 ppb, Broiler chicken 20 ppb, Finisher pig 200 ppb

Canada : 20 ppb (total aflatoxins) for livestock feeds

UK & Spain : Complete feeds 10-20 ppb(B1). Groundnut 50 ppb (B1)

South Africa : 10 ppb(total), Australia : 15 ppb (B1) for groundnut

India : 60 ppb (B1) for groundnut cake, 120 ppb (B1) for groundnut cake (export)

Beef cattle 300 ppb, Layer poultry 100 ppb

Other feed ingredients 200 ppb (B1)

**Table 1.** Suggested limits for aflatoxin.

**1.2. Limits of aflatoxin**

**Limits**

ppb.

Aflatoxins affect mainly liver and kidney and are also carcinogenic and mutagenic (Fig 1). Therefore effective control and detoxification measures need to be undertaken. Toxin pro‐ ducing fungi may invade at pre-harvesting period, harvest-time, during post harvest han‐ dling and in storage. According to the site and time of infestation, the fungi can be divided into three groups: (a) Field fungi (b) Storage fungi (c) Advanced deterioration fungi. Field fungi are generally plant pathogenic fungi; namely *Fusarium*. The storage fungi are *Aspergil‐ lus* and *Penicillium*. The advanced deterioration fungi, normally do not infest intact grains but easily attack damaged grains and requires high moisture content, that include *Aspergil‐ lus clavatus*, *Aspergillus fumigatus*.

Prevention and effective plan for reducing fungal growth and toxin production is very im‐ portant. The recommended practices include 1. Development of fungal resistant varieties of plants, 2. Suitable pre-harvest, harvest and post harvest techniques, 3. Store commodities at low temperature as for as possible, 4. Use fungicides and preservatives against fungal growth and 5. Control of insect damage in grain storage with approved insecticides.

**Figure 1.** Mechanism of cell damage in mycotoxin toxicity.

(adopted from Joshua M Baughman and Vamsi K Mootha, 2006) [6]

The secondary prevention of fungal growth include limiting the growth of infested fungi by re-drying the product, removal of contaminated seeds. The tertiary measures could be to prevent the transfer of fungi and their health hazardous toxins into the food/feed and to the environment. This include complete destruction of the contaminated product or diversion for fermentation to produce ethanol or detoxification / destruction of mycotoxins to the min‐ imum level. Among the mycotoxins, aflatoxin is the most well-known and thoroughly stud‐ ied and its prevention and control has been most successfully practiced in many countries.

cline in aflatoxin production as compared to control. Inoculation of chitosan, *Bacillus subtilis* and *Trichoderma harzianum* to pre-harvest maize along with *Aspergillus flavus* inhibits aflatox‐ in production. Many anti-fungal metabolites (cyclic dipeptides, phenylactic acid, caproic acid, reuterin, lactic acid, acetic acid, fungicin) have been isolated from different cultures of lactic acid bacteria. Aflastin A, an anti-microbial compound produced by *Streptomyces* Spp,. MRI 142 strain of bacteria is known to inhibit aflatoxin production by *Aspergillus parasiticus*. Iturin, an anti-fungal peptide produced by *Bacillus subtilis* had inhibitory effect an *Aspergil‐*

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133

Genetic modification of mold susceptible plants holds some promise in ensuring food safe‐ ty. This involves increasing production of compounds like anti-fungal proteins, hydroxamic acids, and phenolics that reduce fungal contamination. This may be accomplished by intro‐ ducing a novel gene to express the target compound, or enhancing the expression of such compounds by the existing genes, thereby capitalizing on the plant's own defense mecha‐ nisms. Enzymes that catalyze production of anti-fungals could be targeted for their expres‐ sion and such an approach is being actively pursued by researchers. Enhanced expression of an alpha-amylase inhibitor in *Aspergillus* could result in reduced aflatoxin synthesis. Hybrid varieties of cereals with Bt (*Bacillus thermophilus*) genes have shown reduced aflatoxin pro‐

A cluster of genes are responsible for aflatoxin production through pathway-specific tran‐ scriptional regulator. A total of 20 genes in the aflatoxin biosynthetic cluster and 3 addition‐ al genes outside the aflatoxin biosynthetic cluster responsible for aflatoxin production have been identified. Identification of critical genes governing aflatoxin formation could lead to use of non-aflatoxigenic bio-competitive strains of *Aspergillus flavus* through use of gene dis‐ ruption techniques. The advances in molecular biology could aid in early detection of myco‐ toxin production in food/feed material. DNA-chip with microarray system containing oligonucleotide primers that are homologues to genes of several fungal species responsible for the expression of mycotoxins can be employed to forecast the mycotoxin production in advance and accordingly critical anti-fungal strategies can be employed. Such PCR based molecular techniques are of value in assessing the potential for mycotoxin production. The time gap between expression of a set of genes and actual mycotoxin production is about 4-5 days. This early forecasting of extent of mycotoxin production will help in adopting imme‐

Aflatoxins in foods and feeds can be removed, inactivated or detoxified by physical, chemi‐ cal and biological means. The treated products should be health safe from the chemicals and

duction, probably due to higher resistance of plants against pest and insects.

*lus parasiticus*.

*2.2.4. Plant breeding, genetic engineering and microarray*

diate preventive anti-fungal measures.

**2.3. Counteraction / Detoxification of aflatoxins**

their essential nutritive value should not be deteriorated.

### **2.2. Fungal growth inhibition**

The inhibition of fungal growth can be achieved by physical, chemical and biological treat‐ ments. After the crop is harvested, drying and proper storage and suitable transportation of the commodities are of prime importance. Factors contribute to the growth of fungi and tox‐ in production includes high moisture content, humidity, warm temperature (25-40 °C), in‐ sect infestation and grain damage.

#### *2.2.1. Physical methods*


#### *2.2.2. Chemical methods*


#### *2.2.3. Biological methods*

Anti-fungal enzymes, chitinase and Beta -1,3 glucanase found in plant seeds, may act as de‐ fense against pathogenic fungi as chitin and glucan are major polymeric components of many fungal cell walls. Such polysaccharides in fungal cell wall could be enzymatically hy‐ drolysed into smaller products resulting in killing of mycelia or spore of fungi. It is foreseen that seeds rich in such anti-fungal enzymes likely to resist the infestation of fungi. Use of non-toxigenic biocompetitive *Aspergillus* strains to out-compete the toxigenic isolates has been found effective in reducing pre-harvest contamination with aflatoxin in peanut and cotton. However, the aflatoxin contamination process is so compelx that a combination of approaches will be required to eliminate toxin production.

Application of non-toxigenic strains of *Aspergillus flavus* and *Aspergillus parasiticus* to soil in maize plots, favoured the reduction in colonization of toxigenic fungi in subsequent years. When the weather conditions were suitable for fungal growth and resulted in 65-80% de‐ cline in aflatoxin production as compared to control. Inoculation of chitosan, *Bacillus subtilis* and *Trichoderma harzianum* to pre-harvest maize along with *Aspergillus flavus* inhibits aflatox‐ in production. Many anti-fungal metabolites (cyclic dipeptides, phenylactic acid, caproic acid, reuterin, lactic acid, acetic acid, fungicin) have been isolated from different cultures of lactic acid bacteria. Aflastin A, an anti-microbial compound produced by *Streptomyces* Spp,. MRI 142 strain of bacteria is known to inhibit aflatoxin production by *Aspergillus parasiticus*. Iturin, an anti-fungal peptide produced by *Bacillus subtilis* had inhibitory effect an *Aspergil‐ lus parasiticus*.

#### *2.2.4. Plant breeding, genetic engineering and microarray*

environment. This include complete destruction of the contaminated product or diversion for fermentation to produce ethanol or detoxification / destruction of mycotoxins to the min‐ imum level. Among the mycotoxins, aflatoxin is the most well-known and thoroughly stud‐ ied and its prevention and control has been most successfully practiced in many countries.

The inhibition of fungal growth can be achieved by physical, chemical and biological treat‐ ments. After the crop is harvested, drying and proper storage and suitable transportation of the commodities are of prime importance. Factors contribute to the growth of fungi and tox‐ in production includes high moisture content, humidity, warm temperature (25-40 °C), in‐

**•** Use of fungicides (acetic acid, propionic acid, benzoic acid, citric acid and their sodium

**•** Addition of herbal extracts (garlic, onion, clove oil, turmeric powder, thyme) : 0.25-0.5%

Anti-fungal enzymes, chitinase and Beta -1,3 glucanase found in plant seeds, may act as de‐ fense against pathogenic fungi as chitin and glucan are major polymeric components of many fungal cell walls. Such polysaccharides in fungal cell wall could be enzymatically hy‐ drolysed into smaller products resulting in killing of mycelia or spore of fungi. It is foreseen that seeds rich in such anti-fungal enzymes likely to resist the infestation of fungi. Use of non-toxigenic biocompetitive *Aspergillus* strains to out-compete the toxigenic isolates has been found effective in reducing pre-harvest contamination with aflatoxin in peanut and cotton. However, the aflatoxin contamination process is so compelx that a combination of

Application of non-toxigenic strains of *Aspergillus flavus* and *Aspergillus parasiticus* to soil in maize plots, favoured the reduction in colonization of toxigenic fungi in subsequent years. When the weather conditions were suitable for fungal growth and resulted in 65-80% de‐

**•** Drying seeds and commodities to the safe moisture level (< 9-11%).

**•** Maintenance of the container or store house at low temperature and humidity.

**2.2. Fungal growth inhibition**

132 Aflatoxins - Recent Advances and Future Prospects

sect infestation and grain damage.

**•** Keep out insects and pests from the storage.

salts, copper sulfate): 0.2–0.4 % in feed.

approaches will be required to eliminate toxin production.

**•** Use of fumigants – ammonia: 0.2-0.4%

**•** Gamma-irradiation of large-scale commodities. **•** Dilution of the contaminated feed with safe feed.

*2.2.1. Physical methods*

*2.2.2. Chemical methods*

*2.2.3. Biological methods*

Genetic modification of mold susceptible plants holds some promise in ensuring food safe‐ ty. This involves increasing production of compounds like anti-fungal proteins, hydroxamic acids, and phenolics that reduce fungal contamination. This may be accomplished by intro‐ ducing a novel gene to express the target compound, or enhancing the expression of such compounds by the existing genes, thereby capitalizing on the plant's own defense mecha‐ nisms. Enzymes that catalyze production of anti-fungals could be targeted for their expres‐ sion and such an approach is being actively pursued by researchers. Enhanced expression of an alpha-amylase inhibitor in *Aspergillus* could result in reduced aflatoxin synthesis. Hybrid varieties of cereals with Bt (*Bacillus thermophilus*) genes have shown reduced aflatoxin pro‐ duction, probably due to higher resistance of plants against pest and insects.

A cluster of genes are responsible for aflatoxin production through pathway-specific tran‐ scriptional regulator. A total of 20 genes in the aflatoxin biosynthetic cluster and 3 addition‐ al genes outside the aflatoxin biosynthetic cluster responsible for aflatoxin production have been identified. Identification of critical genes governing aflatoxin formation could lead to use of non-aflatoxigenic bio-competitive strains of *Aspergillus flavus* through use of gene dis‐ ruption techniques. The advances in molecular biology could aid in early detection of myco‐ toxin production in food/feed material. DNA-chip with microarray system containing oligonucleotide primers that are homologues to genes of several fungal species responsible for the expression of mycotoxins can be employed to forecast the mycotoxin production in advance and accordingly critical anti-fungal strategies can be employed. Such PCR based molecular techniques are of value in assessing the potential for mycotoxin production. The time gap between expression of a set of genes and actual mycotoxin production is about 4-5 days. This early forecasting of extent of mycotoxin production will help in adopting imme‐ diate preventive anti-fungal measures.

#### **2.3. Counteraction / Detoxification of aflatoxins**

Aflatoxins in foods and feeds can be removed, inactivated or detoxified by physical, chemi‐ cal and biological means. The treated products should be health safe from the chemicals and their essential nutritive value should not be deteriorated.

#### *2.3.1. Physical methods*

Physically, aflatoxin contaminated seeds can be removed by hand picking or photoelectric detecting machines, but this is labor intense and expensive. Heating and cooking under pressure can destroy nearly 70% aflatoxin. Dry roasting can reduce about 50-70% of aflatox‐ in and sunlight drying of aflatoxin contaminated feed could reduce the toxin level by more than 70%.

kg of clay. This binder reduces the AFM1 content of milk by 58% in cows given a diet conta‐

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Probiotic strain of *Lactobacillus acidophilus* CU028 has shown to bind aflatoxin. Probiotic fer‐ mented milk containing *Lactobacillus casei* and *Lactobacillus rhamnosus* strains alone or in combination with chlorophyllin exhibited protective effect against aflatoxin B1- induced hepatic damage. Acid treated lactic acid bacteria were able to bind high dosage of aflatoxin

Dual cultivation of *Aspergillus niger*, *Mucor racemosus*, *Alternaria alternata*, *Rhizopus oryzae* and *Bacillus stearothermophilus* with toxigenic strain of *Aspergillus flavus* results in 70-80% degra‐ dation of aflatoxins. Certain microbes are also able to metabolize mycotoxins (*Corynebacteri‐ um rubrum*) in contaminated feed or to biotransform them(*Rhizopius*, *Trichosporon mycotoxinivorans*, *Rhodotorula rubra, Geotrichum fermentans*). However, these biological proc‐ esses are generally slow and have a varied efficiency. Ruminants are considered to be rela‐ tively resistant to aflatoxins, due to biodegrading and biotransforming ability of rumen microbes compared to monogastric animals. This would be a great asset in biological detoxi‐ fication of aflatoxins and with the help of genetic engineering techniques, benefits of this can

*Saccharomyces cerevisiae* 1 8 3 3 *Condida krusei* 4 5 1 1

*Trichosporon mucoides* 1 - - - *Candida catenulanta* 1 - - -

*Lactobacillus plantarum* - - 4 1 *Lactobacillus fermentum* - - - 1 *Pediococcus acidilactici* - - 1 -

**Table 2.** Aflatoxin binding ability of different strains of yeast and bacteria.

**Number of aflatoxin B1 binding strains Percentage of binding <15 15-39 40-59 >60**

minated with AFB1 at a concentration of 0.05% of dry mater.

in gut conditions.

*2.3.4. Biotransformation*

be better realized.

*Candida parapsilosis*

**Yeast**

**Bacteria**

**Isolates**

The addition of binding agents can reduce the bioavailability of these compounds in ani‐ mals, and limit the presence of toxin residues in animal products. In case of aflatoxin B1 (AFB1), hydrated sodium calcium aluminosilicates (HSCAS) and phyllosilicates derived from natural zeolites have a high affinity, both i*n vitro* and *in vivo*. Zeolites, which are hy‐ drated aluminosilicates of alkaline cations are able to adsorb AFB1. Bentonites have been shown to be effective for the adsorption of AFB1. Other clays, such as kaolin, sepiolite and montmorillonite, bind AFB1 but less effectively than HSCAS and bentonite. Activated char‐ coal has mixed results against AFB1.

Although clays are effective against aflatoxins, caution should be exercised to make sure that their inclusion level is not too high and they are free from impurities such as dioxin. When the level of inclusion is very high, which is actually required for them to be effective, there are chances that these compounds can bind minerals and antibiotics like monensin. Some of the binders are not biodegradable and could pose environmental problem.

#### *2.3.2. Chemical methods*

A variety of chemical agents such as acids, bases (ammonia, caustic soda), oxidants (hydro‐ gen peroxide, ozone, sodium hypochlorite), reducing agents (Bisulphites), chlorinated agents and formaldehyde have been used to degrade mycotoxins in contaminated feeds par‐ ticularly aflatoxins. However, these techniques are not totally safe, are expensive and not well accepted by consumers.

#### *2.3.3. Biological / microbiological methods*

The biological decontamination of mycotoxins using yeast *Saccharomyces cerevisiae* and lactic acid bacteria has received much attention. Yeast and lactic acid bacterial cells are known to bind different toxins on the cell wall surface. This will be of immense value in reducing the mycotoxin hazards (Table 2), and effective binding strains of these microbes could eventual‐ ly be used to minimize aflatoxin exposure and improving overall health in animals.

To tackle the high inclusion levels of clays, cell walls of specific yeasts were studied for their ability to bind aflatoxins. The wealth of data to date has shown that beta-glucans (esterified glucomannans), specific sugars present in the inner cell wall of yeast, can bind aflatoxins. The levels of inclusion of yeast-based binders are much lower than clay-based binders. About 500 gm of glucomannans from yeast cell-wall have the same adsorption capacity as 8 kg of clay. This binder reduces the AFM1 content of milk by 58% in cows given a diet conta‐ minated with AFB1 at a concentration of 0.05% of dry mater.

Probiotic strain of *Lactobacillus acidophilus* CU028 has shown to bind aflatoxin. Probiotic fer‐ mented milk containing *Lactobacillus casei* and *Lactobacillus rhamnosus* strains alone or in combination with chlorophyllin exhibited protective effect against aflatoxin B1- induced hepatic damage. Acid treated lactic acid bacteria were able to bind high dosage of aflatoxin in gut conditions.

#### *2.3.4. Biotransformation*

*2.3.1. Physical methods*

134 Aflatoxins - Recent Advances and Future Prospects

coal has mixed results against AFB1.

*2.3.2. Chemical methods*

well accepted by consumers.

*2.3.3. Biological / microbiological methods*

than 70%.

Physically, aflatoxin contaminated seeds can be removed by hand picking or photoelectric detecting machines, but this is labor intense and expensive. Heating and cooking under pressure can destroy nearly 70% aflatoxin. Dry roasting can reduce about 50-70% of aflatox‐ in and sunlight drying of aflatoxin contaminated feed could reduce the toxin level by more

The addition of binding agents can reduce the bioavailability of these compounds in ani‐ mals, and limit the presence of toxin residues in animal products. In case of aflatoxin B1 (AFB1), hydrated sodium calcium aluminosilicates (HSCAS) and phyllosilicates derived from natural zeolites have a high affinity, both i*n vitro* and *in vivo*. Zeolites, which are hy‐ drated aluminosilicates of alkaline cations are able to adsorb AFB1. Bentonites have been shown to be effective for the adsorption of AFB1. Other clays, such as kaolin, sepiolite and montmorillonite, bind AFB1 but less effectively than HSCAS and bentonite. Activated char‐

Although clays are effective against aflatoxins, caution should be exercised to make sure that their inclusion level is not too high and they are free from impurities such as dioxin. When the level of inclusion is very high, which is actually required for them to be effective, there are chances that these compounds can bind minerals and antibiotics like monensin.

A variety of chemical agents such as acids, bases (ammonia, caustic soda), oxidants (hydro‐ gen peroxide, ozone, sodium hypochlorite), reducing agents (Bisulphites), chlorinated agents and formaldehyde have been used to degrade mycotoxins in contaminated feeds par‐ ticularly aflatoxins. However, these techniques are not totally safe, are expensive and not

The biological decontamination of mycotoxins using yeast *Saccharomyces cerevisiae* and lactic acid bacteria has received much attention. Yeast and lactic acid bacterial cells are known to bind different toxins on the cell wall surface. This will be of immense value in reducing the mycotoxin hazards (Table 2), and effective binding strains of these microbes could eventual‐

To tackle the high inclusion levels of clays, cell walls of specific yeasts were studied for their ability to bind aflatoxins. The wealth of data to date has shown that beta-glucans (esterified glucomannans), specific sugars present in the inner cell wall of yeast, can bind aflatoxins. The levels of inclusion of yeast-based binders are much lower than clay-based binders. About 500 gm of glucomannans from yeast cell-wall have the same adsorption capacity as 8

ly be used to minimize aflatoxin exposure and improving overall health in animals.

Some of the binders are not biodegradable and could pose environmental problem.

Dual cultivation of *Aspergillus niger*, *Mucor racemosus*, *Alternaria alternata*, *Rhizopus oryzae* and *Bacillus stearothermophilus* with toxigenic strain of *Aspergillus flavus* results in 70-80% degra‐ dation of aflatoxins. Certain microbes are also able to metabolize mycotoxins (*Corynebacteri‐ um rubrum*) in contaminated feed or to biotransform them(*Rhizopius*, *Trichosporon mycotoxinivorans*, *Rhodotorula rubra, Geotrichum fermentans*). However, these biological proc‐ esses are generally slow and have a varied efficiency. Ruminants are considered to be rela‐ tively resistant to aflatoxins, due to biodegrading and biotransforming ability of rumen microbes compared to monogastric animals. This would be a great asset in biological detoxi‐ fication of aflatoxins and with the help of genetic engineering techniques, benefits of this can be better realized.


**Table 2.** Aflatoxin binding ability of different strains of yeast and bacteria.

#### **2.4. Dietary manipulations**

#### *2.4.1. Hepatotropic nutrients and anti-oxidants*

Various nutritional strategies have been employed to alleviate the adverse effects of aflatox‐ ins. Addition of specific amino acids like methionine in excess of their requirement protect the chicks from growth depressing effects of AFB1, possibly through an increased rate of de‐ toxification by glutathione, a sulfur amino acid metabolite. Supplementation of phenyl ala‐ nine has shown to alleviate toxicity of ochratoxin. Addition of vegetable oil (safflower oil, olive oil) to aflatoxin contaminated feed improves the performance of chicks.

binder. They are present in over 120 countries and operates on ACE Principle- providing solutions to the animal industry which are friendly to animals, consumer and environment

Recent Advances for Control, Counteraction and Amelioration of Potential Aflatoxins in Animal Feeds

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137

and P. Mahajan2

[1] Bakutis, B., Baliukoniene, V., & Paskevicius, A. (2005). Use of biological method for

[2] Bhatnagar, D., Payne, G. A., Linz, J. E., & Cleveland, T. E. (1995). Molecular biology

[3] Byun, J. R., & Yoon, Y. H. (2003). Binding of aflatoxin G1, G2 and B2 by probiotic Lac‐ tobacillus spp. *Asian- Australasian Journal of Animal Science.*, 16(11), 1686-1689.

[4] Cleveland, T. E., Cary, J. W., Brown, R. L., Bhatnagar, D., Yu, J., Chang, P. K., Chlan, C. A., & Rajasekaran, K. (1997). Use of biotechnology to eliminate aflatoxin in pre‐ harvest crops. *Bulletin of the Institute for Comprehensive Agricultural Sciences., Kinki*

[5] Cuero, R. G., Duffus, E., Osuji, G., & Pettit, R. (1991). Aflatoxin control in preharvest maize : effects of chitosan and two microbial agents. *Journal of Agricultural Science.*,

[6] D'Mello, J. P. F., Placinta, C. M., & Macdonald, A. M. C. (1999). Fusarium mycotox‐ ins : a review of global implications for animal health, welfare and productivity. *Ani‐*

[7] Devegowda, G., Raju, M. V. L. N., & Swamy, H. V. L. N. (1998). Mycotoxins in poul‐

[8] Dorner, T. W., Cole, R. J., & Wicklow, D. T. (1999). Aflatoxin reduction in corn through field application of competitive fungi. *Journal of Food Protection*, 62(6),

[9] Faraj, M. K., Smith, J. E., & Harran, G. (1993). Aflatoxin biodegradation :effects of

try feed: Methods of control and prevention. *Poult. Punch.*, 6, 73-81.

temperature and microbes. *Mycotoxin Research.*, 97(11), 1388-1392.

1 National Institute of Animal Nutrition and Physiology, Bangalore, India

detoxification of mycotoxins. *Botanica Lithuania.*, 7, 123-129.

to eliminate aflatoxin. *Int. News Fats oils Related Mater.*, 6, 262-271.

**Author details**

**References**

N.K.S. Gowda1\*, H.V.L.N. Swamy2

*University*, 5, 75-90.

117(2), 165-169.

650-656.

\*Address all correspondence to: nksgowda@rediffmail.com

2 Alltech Biotechnology Private Ltd., Bangalore , India

*mal Feed Science and Technology*, 80, 183-205.

Aflatoxins cause toxicity through release of free radicals and lipid peroxidation. Hence, anti‐ oxidants could aid in the overall detoxification process in liver and hence may help in allevi‐ ation of aflatoxicosis. Butylated hydroxy toluene (BHT) is effective in preventing the adverse effects of AFB1. Vitamin E and Selenium supplementation also has shown to overcome nega‐ tive effects of aflatoxin. Of late, there is a growing interest in the use of phytochemicals (cur‐ cumin, flavonoids, resveratrol, Allixin, polyphenolics) as antioxidants in increasing the activity of antioxidant enzymes (SOD, catalase, glutathione peroxidase) and neutralizing the free radicals, thus, ameliorating the mycotoxin toxicity.

#### **3. Conclusion**

Aflatoxins are common in nature, hence minimizing the contamination is not an a easy task due to the interaction of fungus with environment and feed material. This involves con‐ stant attention during the entire process of grain harvest, storage, feed manufacturing and animal production. Most effective methods (physical, chemical, biological, biotechnologi‐ cal) to improve seed production, cultivation, harvest and storage need to be adopted. Use of binders and understanding their mechanism of action is the current concept and re‐ search areas in the use of microbes for decontamination and biotransformation of aflatox‐ ins is gaining momentum. Biotechnological intervention in terms of developing transgenic fungal resistant crops and biological control using non-toxigenic, competitive fungal spe‐ cies holds a better promise in managing the problem of aflatoxicosis. Advancement in mo‐ lecular techniques using fungal oligonucleotide probes with PCR based microarray analysis would help in early forecasting / detection of potential aflatoxin production, suggesting for critical control strategies.

#### **Acknowledgements**

The first author wishes to thank and acknowledge the technical and financial support of M/S. Alltech Biotechnology Private Ltd., Bangalore in publishing this chapter. This company is a leading manufacturer and marketer of natural feed supplements including mycotoxin binder. They are present in over 120 countries and operates on ACE Principle- providing solutions to the animal industry which are friendly to animals, consumer and environment
