• Journal of Environmental Health Sciences
• /
• v.10 no.2
• /
• pp.89-97
• /
• 1984

The possible effects of garlic (Aliium sativurn L.) extract on growth and aflatoxin production by Aspergillus parasiticus R- 716 were investigated. Various solvent extracts of garlic strongly inhibited growth and sporulation by Aspergillus parasiticus R-716, and effective solvents used for extraction of garlic were chloroform, benzene, and water-chloroform. The growth and aflatoxin production decreased with the increase in extract concentration, and extract equivalent 1.5g of raw garlic weight in 25ml SLS medium completely inhibited, and at a level of 1.25g garlic, total aflatoxin was reduced 64% (472 ${\mu}g$/25ml) of that produced in the control (1, 352 ${\mu}g$/25 ml). During cultivation inhibitory rate of growth was reduced from 89.1% to 40% and aflatoxin $B_2$, $G_1$ production increased with the laps of time. Especially garlic extract appeared to have a stimulatory effect on lipid accumulation on the contrary aflatoxin production.

• Journal of Food Hygiene and Safety
• /
• v.11 no.1
• /
• pp.35-39
• /
• 1996

The effect of allyisothiocyanate, the mahor compound of radish on the growth of Aspergillus parasiticus R-716 and aflatoxin production, was investigated. An increase in the level of allylisothiocyanate results in a decrease both growth and aflatoxin per myclial weight, and the addition of 125 ppm allylisothocynate completely inhibited the growth of the strain. The addition of allylisothiocyanate to the culture of R-716 strain the production of aflatoxin. The inhibition of aflatoxin was more B-group than G-group and M-group during cultural period. The growth of strain and aflatoxin production were greatly affected by the addition of allylisothiocyanate.

• Journal of Food Hygiene and Safety
• /
• v.1 no.1
• /
• pp.23-29
• /
• 1986

In this study, th effective extraction of 5 vegetables, which have been shown to inhibit the growth of the aflatoxin production of Aspergillus parasiticus R-716, was investigated and their effects were examined. Radish, cabbage, garlic and zinger were effectively with water-chloroform, but crown daisy with n-hexane. Among them, water-chloroform extract of radish was remarkably effective, and garlic extract only inhibited the growth strongly. The growth and the aflatoxin production of the strain were showed 0.758g/25ml, 763ug/25ml with the addition of water-chloroform extract equivalent 15g of raw radish, and an increase in the level of radish extract resulted in a decrease both the growth and the aflatoxin production per mycerial weight.

• Journal of Environmental Health Sciences
• /
• v.33 no.3
• /
• pp.190-194
• /
• 2007

Aflatoxin $B_1$ is a mycotoxin produced by Aspergillus flavus and A. parasiticus and is a human carcinogen. This study was performed to investigate reduction of growth and aflatoxin production of A. parasiticus by kimchi. A. parasiticus was grown in a modified APT broth with the juice of kimchi (at a concentration of 7%) at $28^{\circ}C$ for 9 days. Aflatoxin $B_1$ was determined by use of high performance liquid chromatography (HPLC). The addition of the juice of kimchi significantly reduced mycelial growth and aflatoxin production during the incubation period (p<0.05). Reduction of mycelial growth of A. parasiticus as the result of addition of the juice of kimchi was observed to range between 64.8 to 83.4% while reduction of aflatoxin production ranged from 62.2 to 73.0%. This study indicates that kimchi could be an effective inhibitor of aflatoxin production although mycelial growth may be permitted. More research is needed to study the inhibitory effects of the metabolites of kimchi.

• Korean Journal of Microbiology
• /
• v.23 no.4
• /
• pp.259-264
• /
• 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 the Korean Society of Food Science and Nutrition
• /
• v.13 no.1
• /
• pp.117-126
• /
• 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 environmental and Sanitary engineering
• /
• v.1 no.1 s.1
• /
• pp.109-117
• /
• 1986

As a part of study on prevention from aflatoxin contamination of food and agricultural products, the effects of chloroform extract of various vegetables on the growth and the aflatoxin production by Aspergillus parasiticus R-716 were investigated. Among 15 vegetables tested, garlic, zinger. radish and cabbage were effective in inhibiting the growth of the strain, but eggplant and lettuce slightly accelated. Even though mycelial growth was permitted, 4 vegetables inhibited aflatoxin production in the order of radish, zinger, crown daisy and cabbage, on the contrary, edible burdock and red pepper increased. Especially radish was shown to reduce the aflatoxin production per mycelial weight most. With the addition of chloroform extract equivalent 30g of raw radish on solid media of rice and barley, aflatoxin production of the strain was also inhibited about $80\%$ (484ug, 191ug) of that produced in the control (1796ug, l049ug).

• Journal of Environmental Health Sciences
• /
• v.20 no.4
• /
• pp.90-97
• /
• 1994

This study was performed to investigate the effect of the Panax ginseng C. A. Meyer on the growth and production of aflatoxin by Aspergillus flayus ATCC 15517. Asp. fiavus with 10$^6$ conidia was incubated at 30$\circ$C for 7 days on YES broth containing 0.1%, 0.5%, and 1.0% of ginseng extract. After incubation, dry mycelial weight, pH, and production of aflatoxin were investigated. The results were as follows:There was no significant difference in dry mycelial weight by the addition of 0.1% and 0.5% ginseng extract. However, it was decreased to the rate of 13.7% by the addition of 1.0% ginseng extract in 7 days. pH changes in cultures were similar regardless of the concentration of ginseng extract. The pH values decreased to minimum in 5 days and again increased. Aflatoxin production was reduced as the concentration of ginseng extract increased. When compared to the control, the production of total aflatoxin significantly reduced to 56.7%, 54.0%, 53.3% in the media of 0.1%, 0.5% and 1.0% of ginseng extract, respectively. No significant difference was observed among ginseng extract groups.

• Korean Journal of Microbiology
• /
• v.24 no.4
• /
• pp.352-356
• /
• 1986

A study was carried out to determine the effect of ginseng saponin an its related materials on aflatoxin production by Aspergillus parasiticus NRRL2999 in glucose-salts(GS) medium. Maximal growth of the mold and AF froduction in the medium occurred after 5 and 9 days at $28^{\circ}C$, respectively. When various concentrations of saponin added to the medium aflatoxin synthesis were significantly reduced (p<0.05) compared to the control after 9 days at $28^{\circ}C$. 0.05% of saponin inhibited aflatoxin production most effectively in the low concerntrations of saponin (0.01-0.2%) and the toxin synthesis reduced with an increasing concentrations of saponin in the high concentrations (0.03-5.0%). Various concentrations (0.01-1.0%) of saponin diol and triol in the media also caused to reduce aflatoxin synthesis by the mold (p<0.05). All saponin fractions were found to decrease aflatoxin production significantly. Saponin fraction numbers of 1,2,4 and 6 were shown to reduce aflatoxin production effectively, and the number 1 was the most effective. Addition of 0.05% of nucleic acid related materials to the medium reduced aflatoxin production (p<0.05). Aflatoxins could not be found in broth at all, but in mycelia when 0.05% of caffeine was added to the medium. Aflatoxin synthesis was well correlated with total lipid synthesis, growth and glucose uptake. When aflatoxin synthesis inhibited (5.0% of saponin) both total lipid synthesis and growth were stimulated and the efficiency of glucose utilization was reduced.

• Journal of Food Hygiene and Safety
• /
• v.7 no.1
• /
• pp.15-22
• /
• 1992

This study was conducted to determine the potential of grapefruit seed extract to support Aspergillus parasilicus growth and aflatoxin production. The grapefruit seed extract inhibited the growth and aflatoxin production of the fungi in the level of more than 4,000 ppm and 3,000 ppm in the medium, respectively. Grapefruit seed extract appears to block the conversion of acetate, averufin and versiconal acetate into aflatoxin in vitro experiments. The addition of grapefruit seed extract to the feeding experiment systems did not inhibit the incorporation of 14C-labeled versicolorin A, versicolorin A hemiacetal and sterigmatocystin into aflatoxin. In the electron microscopic examination the biocidal action of grapefruit seed extract was related to the disturbance of cell menbrane funtion, inhibiting cellular respiration.