Mycotoxins
719
were added to irradiated maize, wheat, and barley grains, FB 1 was produced only on maize, not on
the other two.
55
The preservative compounds benzoic acid, BHA, and carvacrol have been shown to inhibit or retard
the mycelial growth of a number of Fusarium spp., with benzoic acid being the most effective followed
by carvacrol and BHA.
93 The simultaneous effect on fumonisin production is unclear.
Prevalence in Corn and Feeds
It has been observed since the mid-1980s that leukoencephalomalacia (LEM) in horses, pulmonary
edema (PE) of porcines, and esophageal cancer (EC) in humans occur in areas of the world where
high levels of fumonisins are found in grain-based foods.
102 For example, the highest rate of human
EC in southern Africa occurs in the Transkei where high levels of FB 1 and FB 2 are found in corn.
Concomitant with the occurrence of the fumonisins is the presence of Fusarium spp., especially
F. moniliforme. The incidence of fumonisin FB 1 in a high-risk county in China was about two
times higher than in a low-risk area, although the differences were not statistically significant.
102
Trichothecenes (mainly deoxynivalenol) in addition to fumonisins were found in corn from the highrisk area. From corn and corn-based products from four states in America, FB 1 was found in 65% of
34 samples while FB 2 was found in only 29%.
37 The upper level for FB 1 was 2679 µg/kg, and 797
µg/kg for FB 2 . Fusarium numbers ranged from 10
2 to >10
5 .
The incidence and prevalence of FB 1 in corn and some corn products in six countries are summarized
in Table 30–2. The highest levels found were in corn from an area in the Transkei, South Africa, where
EC occurred at high rates. The range for these six samples was 3020–117,520 ng/g with a mean of
53,740 ng/g.
89 These levels exceeded those found in 12 samples of moldy corn from the same general
area, where the mean was 23,900 ng/g.
70 Overall, FB 1 was found at lower levels in corn grits, while
in corn meal levels tended to be higher (Table 30–2).
Feed samples from 11 U.S. states were examined for FB 1 .
72 Of the 83 equine feeds that were
associated with equine LEM, 75% contained >10 µg/g with a range of <1.0–126 µg/g. Of the 42
associated with porcine PE syndrome, 71% contained >10 µg/g with a range of <1.0–330 µg/g. On
the other hand, all 51 samples of nonproblem feeds had <9 µg/g of FB 1 , with 94% of the 51 being
<6 µg/g.
72 Of 71 retail samples of corn-based and other grain products in Michigan, 11 contained
fumonisins including 10 of 17 corn-based products.
65 The highest level of FB 1 found using ELISA
was 15.6 µg/g in blue corn meal.
65 Based on literature reports of FB 1 in maize, it has been estimated
that people in the Netherlands may be exposed to an intake of 1000 ng/day.
25
When Fusarium-contaminated corn that was associated with outbreaks of mycotoxicosis in various
animals in Brazil was examined for FB 1 and FB 2 , 20 of 21 samples revealed FB 1 levels that ranged
from 200 to 38,500 ng/g, and 18/21 had an FB 2 range of 100–12,000 ng/g.
88 Except for one isolate
from this corn, all were acutely toxic to ducklings. In a 1996–1997 study of fumonisins in Spanish
beers, 14 were positive at levels from 4.76 to 85.53 ng/ml.
95
Physical/Chemical Properties of FB 1 and FB 2
The chemical structure of FB 1 and FB 2 is indicated below.
26 The two differ only by FB 1 having an
–OH group in lieu of an H on carbon 10. These toxins differ from most others in this chapter in two
ways: they do not possess cyclic or ring groups, and they are water soluble. On the other hand, they
are heat-stable, as are many other mycotoxins. In one study, lyophilized culture materials containing
FB 1 were boiled for 30 minutes and then oven dried at 60
◦ C for 24 hours without loss of toxic
activity.
2
719
were added to irradiated maize, wheat, and barley grains, FB 1 was produced only on maize, not on
the other two.
55
The preservative compounds benzoic acid, BHA, and carvacrol have been shown to inhibit or retard
the mycelial growth of a number of Fusarium spp., with benzoic acid being the most effective followed
by carvacrol and BHA.
93 The simultaneous effect on fumonisin production is unclear.
Prevalence in Corn and Feeds
It has been observed since the mid-1980s that leukoencephalomalacia (LEM) in horses, pulmonary
edema (PE) of porcines, and esophageal cancer (EC) in humans occur in areas of the world where
high levels of fumonisins are found in grain-based foods.
102 For example, the highest rate of human
EC in southern Africa occurs in the Transkei where high levels of FB 1 and FB 2 are found in corn.
Concomitant with the occurrence of the fumonisins is the presence of Fusarium spp., especially
F. moniliforme. The incidence of fumonisin FB 1 in a high-risk county in China was about two
times higher than in a low-risk area, although the differences were not statistically significant.
102
Trichothecenes (mainly deoxynivalenol) in addition to fumonisins were found in corn from the highrisk area. From corn and corn-based products from four states in America, FB 1 was found in 65% of
34 samples while FB 2 was found in only 29%.
37 The upper level for FB 1 was 2679 µg/kg, and 797
µg/kg for FB 2 . Fusarium numbers ranged from 10
2 to >10
5 .
The incidence and prevalence of FB 1 in corn and some corn products in six countries are summarized
in Table 30–2. The highest levels found were in corn from an area in the Transkei, South Africa, where
EC occurred at high rates. The range for these six samples was 3020–117,520 ng/g with a mean of
53,740 ng/g.
89 These levels exceeded those found in 12 samples of moldy corn from the same general
area, where the mean was 23,900 ng/g.
70 Overall, FB 1 was found at lower levels in corn grits, while
in corn meal levels tended to be higher (Table 30–2).
Feed samples from 11 U.S. states were examined for FB 1 .
72 Of the 83 equine feeds that were
associated with equine LEM, 75% contained >10 µg/g with a range of <1.0–126 µg/g. Of the 42
associated with porcine PE syndrome, 71% contained >10 µg/g with a range of <1.0–330 µg/g. On
the other hand, all 51 samples of nonproblem feeds had <9 µg/g of FB 1 , with 94% of the 51 being
<6 µg/g.
72 Of 71 retail samples of corn-based and other grain products in Michigan, 11 contained
fumonisins including 10 of 17 corn-based products.
65 The highest level of FB 1 found using ELISA
was 15.6 µg/g in blue corn meal.
65 Based on literature reports of FB 1 in maize, it has been estimated
that people in the Netherlands may be exposed to an intake of 1000 ng/day.
25
When Fusarium-contaminated corn that was associated with outbreaks of mycotoxicosis in various
animals in Brazil was examined for FB 1 and FB 2 , 20 of 21 samples revealed FB 1 levels that ranged
from 200 to 38,500 ng/g, and 18/21 had an FB 2 range of 100–12,000 ng/g.
88 Except for one isolate
from this corn, all were acutely toxic to ducklings. In a 1996–1997 study of fumonisins in Spanish
beers, 14 were positive at levels from 4.76 to 85.53 ng/ml.
95
Physical/Chemical Properties of FB 1 and FB 2
The chemical structure of FB 1 and FB 2 is indicated below.
26 The two differ only by FB 1 having an
–OH group in lieu of an H on carbon 10. These toxins differ from most others in this chapter in two
ways: they do not possess cyclic or ring groups, and they are water soluble. On the other hand, they
are heat-stable, as are many other mycotoxins. In one study, lyophilized culture materials containing
FB 1 were boiled for 30 minutes and then oven dried at 60
◦ C for 24 hours without loss of toxic
activity.
2