Furylfuramide Research Articles

Deactivation of furyl furamide (AF-2) by rat-liver microsomes and its implication in short-term tests for mutagenicity/carcinogenicity

The genetic activity of AF-2 in both bacteria and yeast rapidly disappeared in the presence of rat-liver microsomal fraction (S9 mix). Incubation of AF-2 with S9 mix even for 10 min at 37°C was sufficient to inactivate it completely. Data available in the literature suggest that activation of AF-2 is necessary for its geno-toxic effect. The activation step may involve reduction of the nitrofuran to an amino group probably by the enzyme reductase I. Most cultured cell systems, such as bacteria, yeast, Neurospora, mammalian cells and human lymphocytes, can probably bring about this reduction. However, the rapid disappearance of the genetic activity of AF-2 in the presence of rat-liver homogenate suggests that rat-liver microsomes may further metabolize the reduction products to inactive forms. Thus, it becomes necessary to test even those chemicals that are mutagenic per se, with mammalian microsomal preparations before their mutagenic/carcinogenic potentialities can be assessed in short-term tests.

A Bacteriological Study on the Preservability of Vienna Sausage (II)

Furylfuramide (FF) and sorbic acid (SOA) were examined for inhibitory effects on growth in vitro of 75 strains of 15 genera of bacteria isolated from vienna sausage.The results obtained are summarized as follows.(1) FF (5ppm) and SOA (0.2%) had the inhibitory effects on the growth of Acinetobacter, Alcaligenes, Bacillus, Corynebacterium, Flavobacterium, Micrococcus, Staphylococcus, etc. at 30°C, but failed to inhibit the growth of Comamonas, Lactobacillus, Leuconostoc, Streptococcus, etc.(2) FF and SOA generally displayed a stronger growth-inhibiting effect during incubation at 10°C than that at 30°C.They failed to inhibit the growth of Comamonas, Lactobacillus, Leuconostoc, and Streptococcus during incubation at 10°C.(3) In general, the inhibitory effects of FF and SOA were enhanced when the pH of the culture medium used was less than 5.9.The tendency was more remarkable in SOA than in FF.(4) The minimum growth-inhibiting concentrations of FF and SOA for the isolated bacteria were as follows: 0.16-0.62ppm for Acinetobacter, 5.0-5.0<ppm for Alcaligenes, 0.16ppm for Bacillus, 5.0ppm for Corynebacterium, 0.62-2.5ppm for Elavobacterium, 0.31-1.25ppm for Micrococcus, 5.0ppm for Pseudomonas, and 0.62-5.0 ppm for Staphylococcus.(5) The pH of the medium of a bacterial culture changed distinctly in value when bacterial growth was not inhibited by either chemical.It hardly changed when both chemicals showed an inhibitory effect on the growth of bacteria in the culture.This tendency was more remarkable in the bacterial culture at 30°C than that at 10°C.

Determination of Furylfuramide by Gas Chromatogaphy

Determination of Furylfuramide by Gas Chromatogaphy

ニトロフラン誘導体の食品防腐剤としての研究-XVI.

The effects of furylfuramide (FF) on the germination and successive outgrowth of two bacterial spores were investigated by measuring the change in optical density of spore suspensions under several exposing systems to FF, in order to substantiate the microscopic observations which suggested that this drug acted to inhibit the outgrowth not at germination, but during the stage from “swelling” to “emergence” in the developmental process of the bacterial spore. The results obtained were summarized as follows: 1. FF did not inhibit the germination in physiological germinant solution even at ten times more than MIC for both microbes, although in PGY medium the time required to reach minimum optical density was prolonged in proportion to the concentration of FF in the case of B. coagulans. 2. When the dormant spores were exposed to FF in phosphate buffer, it had no effectiveness on either germination or outgrowth, but when the microbes were exposed in physiological germinant, the effect of FF was shown as the prolongation of the lag phase of the outgrowth in the medium without FF.

ニトロフラン誘導体の食品防腐剤としての研究-XIV

The effect of furylfuramide (FF) on germination and outgrowth of two bacterial spores was studied in a slide culture, in order to define the point at which FF acts to prevent the developmental process, from a morphological point of view. Concentrations of FF higher than minimal inhibitory concentration (MIC) did not interfere with the reduction of refractility. However, the developmental process stopped there, and the germinated spores eventually lysed before elongation occurred, shedding the empty spore coats. At less than MIC, many distorted cells appeared and gradually lysed. The bacteriostatic action of FF was shown as a result of the prolongation of their outgrowth. FF acted to arrest the development of bacterial spores not at germination, but after the stage from “swelling” to “emergence”. A discrepancy between the two organisms existed in that many refractile spores of B. coagulans, isolated from spoiled fish sausage, still remained on the culture after 35 hours at 37°C, but not in the case of B. subtilis.

Effect of Furyl Furamide on the Keeping Quality and Bacterial Contamination of Horse Mackerel during Transport under Ice-Chilled Condition

Bacteriological survey was conducted 3 times during July and August in 1967, with respect to the contamination of sea water in Nagasaki Port and the sea waters in the holds of fishing boats. To one of the fish hold in each boat was added furyl furamide (FF) for keeping the quality of fishcatch and the others being non-treated control.In addition, the skins and muscles of horse mackerel samples which had been either treated or non-treated with FF were examined, and the tests were done before and after transport from Nagasaki to Tokyo by rail of rapid service under chilled condition.Results obtained may be summarized as follows:1. The sea water in Nagasaki Port being employed for landing such fishcatch as horse mackerel and common mackerel was found to be highly contaminated showing high plate counts and coliform numbers. Moreover, it was noted that Vibrio parahaemolyticus, one of the most important causative organisms of food poisoning in Japan could be detected throughout the present survey.2. Fairly high bacterial numbers were recorded in the sea water of the control fish holds, while addition of FF at 5ppm to the holds resulted in marked decreases in the number of indicator organisms, and almost no V. parahaemolyticus was detected in the sea water of FF treated fish holds.3. No V. parahaemolyticus was detected in the fish samples when tested immediately after being landed at Nagasaki, whereas the presence of this organism was confirmed in the control samples of the first experiment. Interestingly, almost no Vibrio was detected in the samples which had been treated with FF.

Studies on the Preservation of Cooked Beans

Bacteriological examination was conducted on cooked beans packed in film under vacuum, and the effect of sorbic acid (SOA) and furylfuramide (FF) was investigated for the preservation of the product. Three-layered plate method was very useful for bacteria counting, preventing the rapid spreading of colonies of Bacillus strains. More than thirty strains belonging to B. pumilus, B. megaterium, B. cereus, B. subtilis, B. licheniformis, B. circulans, B. coagulans, Clostridium acetobutyricum, and C. bifermentans were isolated from the products prepared with or without SOA and stored at 37°C for a few days, one and six months. For preventing the growth of non-spore forming bacteria found in the products pasteurized at 85°C for 45min., 1500μg/ml SOA or 10μg/ml FF was necessary at pH 5. 8. The effectiveness of these preservatives decreased significantly with the increase in the number of inoculated bacteria. Some strains isolated from the product, especially of Clostridium, exhibited an ability to decompose SOA. By addition of 1000μg/g SOA or 2.5μg/g FF, the product was preserved for 21 days at 37°C without any spoilage in appearance and without increase in number of bacteria more than 10102-103/g. About half of added FF was lost by heat-treatment and the rest disappeared rapidly during the storage, while SOA decreased to only a limited extent.

Factors Affecting the Stability of Chlortetracycline, Tylosin and Furylfuramide Against Low Level of Ionizing Radiation

SUMMARY— Effect of low levels of ionizing radiation (0.01–0.2 Mrad) on the stability of chlortetracycline (CTC), furylfuramide (FF) and tylosin (Tl) were investigated. Tl in the phosphate buffer of pH 6–8 was very sensitive to low‐level radiation, while either FF or CTC exhibited fairly high resistance at the same dose levels. Removal of dissolved oxygen in the test solution by aerating with nitrogen gas enhanced the inactivation of TI and FF at 0.05–0.1 Mrad of radiation, but it had an opposite effect on the inactivation of CTC. Much higher TI and CTC activities were retained after irradiation at 0.1 or 0.2 Mrad when the drugs were added to albumin, gelatin, broth or minced meats of five species of fish; the retention of FF did not change.The remaining activity of Tl at 0.1 or 0.2 Mrad of radiation was more or less influenced by adding various sugars and amino acids. The presence of sugars (mono‐ or disaccharides) did not change retention of TI markedly, but gave a weak protective effect. Tryptophane, histidine, phenylalanine, methionine and tyrosine exhibited a fairly high protective action on the inactivation of TI after irradiation.

A Simple Method for the Separation of Furyl Furamide in Foods

According to the methods by Arai et al. and Kanno et al. for the chemical assay of 2- (2-furyl) -3- (5-nitro-2-furyl) acryl amide (furyl furamide, FF), FF in a food can be extracted with acidulated toluene-butyl acetate mixture, followed by separation of FF in the solvent fraction by means of an alumina column chromatography. However, the recovery of FF in the aforementioned methods was not so high as 80 to 90% sometimes being as low as 60%.In the present study, a new simple method was devised for the separation of FF in foods by means of partition column chromatography, and by this method, fairly high recovery of FF was obtained as can be seen in Table 2 and Fig. 5. Outline of the new method is as follows:(1) About 3g of the minced sample was mixed with 2g of alumina, 3g of silica gel and 1g of sodium sulfate (anhydrous).(2) The mixture was packed in a glass tube of 1.3cm in diameter tightly, followed by the addition of 5g of silica gel on the top of sample mixture.(3) The column thus prepared was subjected to partition chromatography of ascending method using the mixture of toluene, ethyl acetate and ethanol (2: 2: 1) as a solvent.(4) After development, the FF band of yellow colored portion in the column was taken out to elute with methanol.(5) FF in the eluate was determined colorimetrically according to the method by Kanno et al.

Effect of Furyl Furamide on the Keeping Quality and Bacterial Contamination of Horse Mackerel during Transport under Ice-Chilled Condition

Effect of Furyl Furamide on the Keeping Quality and Bacterial Contamination of Horse Mackerel during Transport under Ice-Chilled Condition

数種食品防腐剤の嫌気性菌に対する発育抑制効果と培地成分の影響

Effect of components of culture media for anerobic bacteria on the sensitivity of various Clostridia to chlortetracycline (CTC), tylosin (TI), furyl-furamide (FF) and nitrofurazone (NFS) have been examined. Test organisms were 9 strains of stock Clostridia including Clostridium perfringens, Cl. tetani, Cl. histolyticum, Cl. sporogenes and 3 types of Cl. botulinum, in addition, 10 strains of Clostridia isolated from fish sausages and fish hams, species names of which were shown in Table 2. Culture media employed in this experiment were the thioglycollate medium (TGC), the brain heart infusion medium containing 0.1% agar (BHI+A), and the BHI medium covered with sterile liquid paraffin (BHI+P) which were adjusted to pH 7. Minimal inhibitory concentrations (MIC) of test drugs were determined in the respective medium containing binary dilution series of each drug after being incubated at 37°C for 24, 48, 72 and 96 hours. Results obtained may be summarized as follows: 1. As to CTC, no significant difference in MIC values was observed according to the kind of culture medium, while these values varied markedly by the length of incubation period which might be due to the instability of CTC in the culture media (Figs. 1 and 2). 2. In the case of TI, much higher MIC values were noted in the TGC medium than those obtained in both of the BHI media in spite of the stability of the drug in the TGC medium, whereas no appreciable change could be seen depending upon the length of incubation period (Table 1). 3. In the TGC medium, FF gave highest MIC values (Table 1), in addition, these values increased greatly according as the incubation period increased. These phenomena might be due to rapid inactivation of the drug by the action of reducing agents in the medium (Fig. 2). To the contrary, MIC values were fairly low when determined in either BHI-A or BHI-P medium, moreover, almost no appreciable change was noted by the length of incubation period (Tables 1 and 2). 4. Growth inhibitory effect of NFS to various Clostridia was found to be the lowest among 4 drugs so far tested, especially almost no activity was observed in the TGC medium which might be explained by the rapid destruction of the drug in the medium during incubation (Fig. 2).

防腐剤フリルフラマイドの微生物的定量法の検討-II

As part of the determination method of furylfuramide (FF) in fish products, the prepara-tion of the test solution for a microbioassay of FF which has been added to ground fish meat or fish sausage was studied, and following results were obtained. The removal of water-soluble components from fish flesh shows no discernible effect of interference on the recovery of FF (Table 1). When the ground meat of whale is stored at 3±1°C, the amount of FF decreased to one-tenth of the initial amount after 96 hours (Table 2). The decrease of FF is also recognized in the case of storage test of homogenated meat (Table 3), however, the recovery of FF seems to differ with different proportion of fish meat and water (Tables 4 and 5). In the preparation of supernatant to be tested from homogenate, the speed of centrifugation affects on the amount of FF in supernatant (Table 6). On the basis of the results presented above, the following method of preparation of test solution was recommended: To one part of sample such as fish sausage, is added three parts of DMF buffer solution, and the mixture blended for 1 minute by homogenizer. The homogenate obtained is centri-fuged at 6000 r.p.m. for 15 minutes, and the supernatant is subjected to the determination of FF.