• Korean Journal of Microbiology
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• v.23 no.4
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• pp.259-264
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• 1985

The research was carried out for the purpose of finding effects of gerbal saponins on aflatoxin synthesis by Aspergillus parasitics NRRL 2999. A. parasiticus with $10^6$ conidia were grown at $30^{\circ}C$ for 9 days on the enriched medium that is optimum for the frowth and aflatoxins production by the mold. The inhibitory effect on the growth and aflatoxins produced by the mold occurred in the presence of 0.36% of crude red-ginseng saponin showing both the growth and aflatoxins production come to 62.3% (growth), 38.7% (aflatoxin $B_1$) and 22.9% (aflatoxin $G_1$) of the control. Thd next effective saponin to inhibit the growth and aflatoxins production was from burdock seeds. However, saponin extracted from honeysuckle flowers had no inhibitory effect. The mold caused no changes in the pH of the medium when it contained red-ginseng saponin. Red-ginseng saponin was more effective than the white-ginseng in inhibiting both the growth and aflatoxin production.

• Journal of Life Science
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• v.19 no.1
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• pp.65-74
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• 2009

The objective of this study was to examine the effects of steam flaking treatment of corn grains imported from USA and India on in vitro gas production, microbial growth and contents of aflatoxin $B_1$ and ochratoxin A. Each treatment was composed of total 4 treatments including (1) USCW (US com-whole type), (2) USCF (US corn-flaked type), (3) IDCW (India corn-whole type) and (4) IDCF (India orn-flaked type) with 4 replications $\times$ 6 incubation times (3, 6, 9, 12, 18 and 24 hr). Mycotoxin (aflatoxin $B_1$ & ochratoxin A) contents in test corns tended to increase gradually with increasing logistics periods from the harbor, hopper, silo to processing line. The contents of aflatoxin $B_1$ in India corn (IDCW) and US corn (USCW) were 11.71 and 1.78 ppb, respectively when measured at the hopper. After steam flaking, both contents of aflatoxin $B_1$ in USCW and IDCW were 0.00 ppb. It means that Aspergillus flavus could be decreased by steam flaking. However, this trend was not observed in ochratoxin content. The gas production rate of USA corns (USCW & USCF) was significantly (p<0.05) higher than India corns (IDCW & IDCF), and that of steam flaked corns (USCF & IDCF) was higher $1.5{\sim}2%$ than whole corns (USCW & IDCW) after 3 hr incubation in in vitro experiment. pH value was optimally maintained for microbial growth during whole incubation times with the value of 6.05 to 6.54, and was not significantly different between treatments, but USCF was somewhat lower than other treatments. pH value decreased following 12 hr of incubation but gas production increased rapidly during the same period. In addition, in vitro microbial growth rates also increased with up to 18 hr of incubation period, thereafter experienced a decrease with extended incubation time. In conclusion, US corn was superior to India corn by origin based on the results of in vitro and mycotoxin contents. And steam flaking process of imported corns tended to decrease mycotoxin contents such as aflatoxin $B_1$ and ochratoxin A as well as improve in vitro gas production and microbial growth rates.

• Asian-Australasian Journal of Animal Sciences
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• v.24 no.7
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• pp.1011-1018
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• 2011

Aflatoxin-contaminated feed cause mortality, suppression of the immune system, reduced growth rates and losses in feed efficiency. This research study was planned to investigate the immunomodulatory and growth promoting effect of milk thistle as feed additive against aflatoxin $B_1$ in broiler chicks at NWFP Agricultural University Peshawar, Pakistan. Two hundred and forty (240) day old broilers chicks were randomly assigned into four major groups AfF, aflatoxin free feed; Aflatoxin $B_1$ was present in the feed at the levels of 80-520 ${\mu}g/kg$ of the feed in the remaining three groups. Aflatoxin contaminated feed was provided for 5 weeks. Group AfB was supplemented with toxin binder "Mycoad" at 3 g/kg of feed and group AfT was supplemented with milk thistle at10 g/kg of feed. Each group was further sub divided into two sub-groups, vaccinated against ND (Newcastle disease), IB (Infectious bronchitis) and IBD (Infectious bursal diseases) according to recommended schedule of vaccination or non vaccinated. Each sub group carried three replicates with 10 chicks per replicate. Chicks were reared in pens in an open sided house. Supplementary heat was provided to all the chicks during brooding period. Mean body weight gain and dressing percentage were significantly (p<0.05) higher in group AfF, followed by AfT, AfB and Af. Weight gain and dressing percentage was the same in group AfB and AfT, while it was significantly lower in group Af. Feed intake, breast, thigh and leg weight were found significantly (p<0.05) higher in group AfF, followed by AfB, AfT and Af. Significantly lower (better) FCR value was recorded in group AfT. Water intake was significantly (p<0.05) higher in group AfT and AfF as compared to other groups. Mortality was significantly (p<0.05) higher in group Af. Mean bursa and thymus weights were found significantly (p<0.05) higher in group AfF, AfB and AfT followed by Af, while higher spleen weight was recorded in group AfT. Mean antibody titer against ND, IB and IBD was significantly (p<0.05) higher in group AfT, as compared to other groups. It is concluded that milk thistle at 10 g/kg of feed could effectively be utilized as immunostimulant and growth promotant in the presence of immunosuppressant aflatoxin $B_1$ in the feed.

• Journal of the Korean Society of Food Science and Nutrition
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• v.13 no.1
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• pp.117-126
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• 1984

Aflatoxins are toxic and carcinogenic secondary metabolites which are produced by trains of A. flavus and A. parasiticus during their growth on foods and feedstuffs. Aflatoxins are a group of closely related heterocyclic compounds of which $B_1$, $B_2$, and $G_2$ are the major members. Aflatoxins are synthesized via a polyketide pathway in which the general steps are acetate, an-thraquinones, xanthone and aflatoxins. Aflatoxin formation is favored by high moisture or high $a_w$(0.95${\sim}$0.99). The limiting $a_w$ for aflatoxin production on agricultural commodities is 0.83. Optimum temperature for aflatoxin production by the molds is $25{\sim}30^{\circ}C$ and the incubation time for the maximum production of the toxin is 7${\sim}$15 days. The limiting temperatures for aflatoxin production are ${\leq}7.5^{\circ}C\;and\;\geq40^{\circ}C$. Cycling temperatures may or may not stimulate aflatoxin production depending on the amplitude of cycling, substrate and strains of molds. Aflatoxin pro-ducing molds are aerobic organisms and thus have a requirement for oxygen. A decreasing $O_2$ concentration and/or increasing concentrations of $CO_2$ or $N_2$ depress the mold growth and aflatoxin formation. A. flavus grows competitively or associatively in the presence of other microorganisms and occasionally loses the competition with other microorganisms. Some lactic acid bacteria have been shown to reduce growth and aflatoxin production by A. parasiticus. Carbon source is the most important nutritional factors affecting aflatoxin formation by the molds. Sucrose, fructose and glucose are the most favorable carbon sources. Food substrates of plant derived products which have high carbohydrate content such as agricultural commodities and their products are most vulnerable to contamination by aflatoxins.

• Journal of the korean veterinary medical association
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• v.26 no.9
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• pp.543-553
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• 1990

This report describes the cellular changes induced in the livers of ducklings by a sin91e administration of aflatoxin B$_1$ produced by Korean Industrial Strain of the Aspergillus flavus, in order to examine the toxicity of the minimum dose of

• Journal of Food Hygiene and Safety
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• v.13 no.3
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• pp.313-317
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• 1998

This study was perfonned to investigate the possible effect of Bacillus subtilis which is the predominant species of bacteria in Korean soy sauce, soy paste, and Meju (soybean cake) on the growth and aflatoxin production of Aspergillus parasiticus ATCC 15517. The microorganisms were grown in a modified APT broth and incubated at $30^{\circ}C$ for 12 days. Aflatoxins were determined using high performance liquid chromatography (HPLC). A remarkable inhibition of the growth of Aspergillus parasiticus was observed during the incubation period when in the presence of B. subtilis (mixed culture). Dry mycelial weight in the mixed culture was significantly reduced by 85.3% in comparison to the control at the end of the incubation period (p<0.01). Lower levels of aflatoxins were found in the mixed culture than in the monoculture. At the end of the incubation period aflatoxin production was significantly inhibited by more than 50% (p<0.05). These results indicate that B. subtilis mainly inhibites the growth and aflatoxin production of toxigenic Aspergillus in Meju, soy sauce and soy paste. Although its effect on aflatoxin production was less pronounced, we could expect more inhibition by another bacteria related with fermentation in Meju.

• Korean Journal of Veterinary Research
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• v.36 no.4
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• pp.887-894
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• 1996

Cyclopiazonic acid(CPA) known as stimulating the release of intracellular calcium, aflatoxin $B_1(AFB_1)$ causing gastrointestinal hemorrhage frequently were used as model toxic mycotoxins in these studies. First of all, the effects of various mycotoxins on the platelet aggregation response were determined. The effects of mycotoxins on the ATP release from platelet by aggregating factors were investigated. The results and conclusions obtained from these studies are : 1) CPA promoted ADP, collagen, thrombin, A.A. and PAF-induced rabbit platelet aggregation. $AFB_1$ inhibited collagen, A.A. and PAF-induced rabbit platelet aggregation only. 2) CPA increased both aggregation and disaggregation time, whereas $AFB_1$ decreased in a dose dependent manner. 3) CPA increased ADP, thrombin, A.A. and PAF-induced ATP release. $AFB_1$ increased A.A.-induced ATP release and decreased PAF-induced release in a dose dependent manner. In conclusion, CPA promoted platelet aggregation by the increase of ATP. Antiaggregating effects of AFB1 may be due to decreases of ATP. These data provide the basis for the future study of roles of ATP release in platelet aggregation.

• Journal of Environmental Health Sciences
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• v.21 no.3
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• pp.48-55
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• 1995

This study was performed to investigate the inhibitory effect of Aloe vera on the growth and aflatoxin production of Aspergillus parasiticus. Spore suspension of A. parasiticus ATCC 15517 was inoculated on the yeast-extract sucrose broth containing 0.1%, 0.5%, 1.0% and 10.0% of chloroform extract of Aloe vera and then incubated at 30$\circ$C for 7 days. Mycelial weight was 160.7 mg/5ml in control group and decreased by the addition of the extract with no significance. The mold caused decrease in pH of the media with and without the extract. pH in the group contained 10.0% of the extract showed significantly higher value of 5.10 than that of 4.90 in control group (p<0.05). Fluorescence spots of four aflatoxins were observed under the 365 nm of UV light after extraction of the media and TLC. In the result of separation and determination by HPLC, the aflatoxins were produced in the order of $B_1, G_1, B_2$ and $G_2$ in all groups. Production of aflatoxins $B_1, B_2$ and $G_1$ was reduced by the addition of the extract and decreased as amount of the extract increased. The production of aflatoxins $B_1$ and $B_2$ significantly reduced when the media contained more than 1.0% of the extract, and $G_1$ more than 0.5%, respectively(p<0.05). No reduction and no significant difference among groups were observed in case of aflatoxin $G_2$. With the above result, the extract of Aloe vera reduced the production of aflatoxin by A. parasiticus though it did not inhibit mycelial growth.

• Korean Journal of Food Science and Technology
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• v.18 no.5
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• pp.345-350
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• 1986

Crude saponins of soybean and Azuki bean (2.0 mg/plate)were most effective against Trp-p-2, and also all of legume saponins (2.0 mg/plate)were excellent effective against aflatoxin $B_1$. Crude saponins of taro, burdock and ginseng were remarkably effective at ranging from 1.0 mg to 2.0 mg per plate against MeIQ. Especially ginseng saponin was excellent effective and arrow root saponins was remarkably effective against MeIQ, respectively. Plant saponins of taro, lotus burdock, arrow root and ginseng except for dodok were most effective activities against aflatoxin $B_1$.

• Applied Biological Chemistry
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• v.31 no.2
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• pp.182-186
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• 1988

The maximal production of aflatoxin $B_1$, and $G_1$ by A. flavus ATCC 15517 was reduced by 98% and 99% respectively, in the mixed culture with A. awamori var. fumeus in comparison with that in the monoculture of A. flavus. An important cause for the reduction in aflatoxin formation was found that A. awamori var. fumeus excreted aflatoxin degrading factor(s) into the medium during the growth which precipitated by the addition of ammonium sulfate $(0{\sim}80%)$.