Protection from cholera by adding lime juice to food - results from community and laboratory studies in Guinea-Bissau, West Africa. (9/138)

Epidemiological studies have shown that food plays an important role in the transmission of Vibrio cholerae, and different foods have been incriminated in many epidemic outbreaks of cholera. Storing contaminated meals at ambient temperatures allows growth of V. cholerae. Some ingredients such as lime juice may inhibit the survival of V. cholerae in foods. During an epidemic caused by V. cholerae O1 in Guinea-Bissau in 1996, a case control study was conducted in the capital Bissau, the main affected region with an attack rate of 7.4%. Cases were hospitalized patients and controls were matched for area, gender and age. Lime juice in the sauce eaten with rice gave a strong protective effect (odds ratio [OR] = 0.31, 95% confidence interval [CI] = 0.17-0.56), and tomato sauce was also protective (OR = 0.36, 95% CI = 0.24-0.54). On the other hand, use of a bucket for storage of water in the house was associated with increased risk (OR = 4.4, CI = 2.21-8.74). Laboratory experiments to elucidate the inhibitory effect of different concentrations of lime juice on survival of V. cholerae in meals showed that V. cholerae thrives in rice with peanut sauce, but lime juice inhibited its growth. Since lime juice is a common ingredient of sauces, its use should be further encouraged to prevent foodborne transmission in the household during cholera outbreaks.  (+info)

Simultaneous determination of sweeteners and preservatives in preserved fruits by micellar electrokinetic capillary chromatography. (10/138)

A micellar electrokinetic capillary method for the simultaneous determination of the sweeteners dulcin, aspartame, saccharin, and acesulfame-K and the preservatives sorbic acid; benzoic acid; sodium dehydroacetate; and methyl-, ethyl-, propyl-, isopropyl-, butyl-, and isobutyl-p-hydroxybenzoate in preserved fruits is developed. These additives are ion-paired and extracted using sonication followed by solid-phase extraction from the sample. Separation is achieved using a 57-cm fused-silica capillary with a buffer comprised of 0.05 M sodium deoxycholate, 0.02 M borate-phosphate buffer (pH 8.6), and 5% acetonitrile, and the wavelength for detection is 214 nm. The average recovery rate for all sweeteners and preservatives is approximately 90% with good reproducibility, and the detection limits range from 10 to 25 microg/g. Fifty preserved fruit samples are analyzed for the content of sweeteners and preservatives. The sweeteners found in 28 samples was aspartame (0.17-11.59 g/kg) or saccharin (0.09-5.64 g/kg). Benzoic acid (0.02-1.72 g/kg) and sorbic acid (0.27-1.15 g/kg) were found as preservatives in 29 samples.  (+info)

Methyl p-hydroxybenzoate (E-218) a preservative for drugs and food is an activator of the ryanodine receptor Ca(2+) release channel. (11/138)

1. Haloperidol is a drug used in the management of several psychotic disorders and its use has been linked to Neuroleptic Malignant Syndrome. In the present study we have investigated the effect of a commercial preparation of haloperidol, Serenase, on skeletal muscle sarcoplasmic reticulum. 2. Addition of Serenase to isolated terminal cisternae caused a rapid release of calcium. We tested whether the active Ca(2+)-releasing substance was haloperidol or another compound present in the preparation. 3. Our results show that methyl p-hydroxybenzoate, one of the preservatives and a commonly used anti-microbial agent (E-218) is an activator of Ca(2+) release (E.C. 50=2.0 mM), mediated by a ruthenium red-sensitive Ca(2+) release channel present in skeletal muscle terminal cisternae.  (+info)

Statistical analysis on toxicity of a nitrofuran derivative, 2-(2-furyl)-3-(5-nitro-2-furyl)acrylamide. (12/138)

A food additive, furylfuramide or AF-2, which had been used in Japan since 1965 and structurally is composed of 5-nitro-2-furyl radical and acrylamide, was re-examined mainly on chronic toxicity by statistically reviewing published data. The conclusions are as follows: 1) The maximum safety dosage which shows no demonstrable change in rats must be corrected at least to 1/170 of the value which has been accepted by the Ministry of Health and Welfare of Japan (MHW). 2) The minimum effective dose to bacterial growth in food can not be lowered below the standard usage level with MHW determined, because the inactivation factor in food, decreasing effectivity to 1/20, must be taken into consideration. 3) In view of these two facts, AF-2 is found to be unacceptable as a food additive. 4) Great importance must also be attached to the possibility of mutagenicity and carcinogenicity of AF-2, pointed out recently. Both neurotoxicity and dermatitis observed in tofu (soybean curd) makers are also memtioned.  (+info)

Redox potential-dependent nitrite metabolism by Salmonella typhimurium. (13/138)

Salmonellae are generally resistant to the inhibitory effects of NaNO2. Removal of the lipopolysaccharide of Salmonella typhimurium by ethylenediaminetetraacetic acid pretreatment did not result in subsequent inhibtion of growth by NaNO2, indicating that lipopolysaccharide does not function to exclude NaNO2 from the cell. NaNO2 disappeared from the medium while the cells were growing, but, after stationary phase was reached, no further losses were observed unless the pH was maintained above 7.0. Similar losses were observed in a cell-free system if the redox potential of the medium was between -250 and -175 mV. If the disrupted cell suspension was first heated in a boiling water bath for 15 to 18 min, no NaNO2 loss was observed regardless of the redox potential. S. typhimurium is capable of metabolizing NaNO2, possibly by means of a nitrite-reducing enzyme function which is redox controlled.  (+info)

Killer toxin of Kluyveromyces phaffii DBVPG 6076 as a biopreservative agent to control apiculate wine Yeasts. (14/138)

The use of Kluyveromyces phaffii DBVPG 6076 killer toxin against apiculate wine yeasts has been investigated. The killer toxin of K. phaffii DBVPG 6076 showed extensive anti-Hanseniaspora activity against strains isolated from grape samples. The proteinaceous killer toxin was found to be active in the pH range of 3 to 5 and at temperatures lower than 40 degrees C. These biochemical properties would allow the use of K. phaffii killer toxin in wine making. Fungicidal or fungistatic effects depend on the toxin concentration. Toxin concentrations present in the supernatant during optimal conditions of production (14.3 arbitrary units) exerted a fungicidal effect on a sensitive strain of Hanseniaspora uvarum. At subcritical concentrations (fungistatic effect) the saturation kinetics observed with the increased ratio of killer toxin to H. uvarum cells suggest the presence of a toxin receptor. The inhibitory activity exerted by the killer toxin present in grape juice was comparable to that of sulfur dioxide. The findings presented suggest that the K. phaffii DBVPG 6076 killer toxin has potential as a biopreservative agent in wine making.  (+info)

Antimicrobial characteristics of chitosans against food spoilage microorganisms in liquid media and mayonnaise. (15/138)

Four different kinds of chitosans were prepared by treating crude chitin with various NaOH concentrations. The antimicrobial activities of the chitosans were tested against four species of food spoilage microorganisms (Lactobacillus plantarum, Lactobacillus fructivorans, Serratia liquefaciens, and Zygosaccharomyces bailii). The initial effect of the chitosans was biocidal, and counts of viable cells were significantly reduced. After an extended lag phase, some strains recovered and resumed growth. The activities of chitosan against these microorganisms increased with the concentration. Chitosan-50 was most effective against L. fructivorans, but inhibition of L. plantarum was greatest with chitosan-55. There was no significant difference among the chitosans in their antimicrobial activity against S. liquefaciens and Z. bailii. The addition of chitosan to mayonnaise significantly decreased the viable cell counts of L. fructivorans and Z. bailii during storage at 25 degrees C. These results suggest that chitosan can be used as a food preservative to inhibit the growth of spoilage microorganisms in mayonnaise.  (+info)

Decreased sperm number and motile activity on the F1 offspring maternally exposed to butyl p-hydroxybenzoic acid (butyl paraben). (16/138)

Butyl p-hydroxybenzoic acid (butyl paraben, BP) is widely used as a preservative in food and cosmetic products. Routledge et al showed that BP is weakly estrogenic in both in vitro and in vivo (rat uterotrophic) analyses. We investigated whether maternal exposures to BP during gestation and lactation periods affected the development of the reproductive organs of the F1 offspring. Pregnant Sprague-Dawley rats were injected subcutaneously with 100 or 200 mg/kg of BP from gestation day (GD) 6 to postnatal day (PND) 20. In the group exposed to 200 mg/kg of BP, the proportion of pups born alive and the proportion of pups surviving to weaning were decreased. The body weights of female offspring were significantly decreased at PND 49. The weights of testes, seminal vesicles and prostate glands were significantly decreased in rats exposed to 100 mg/kg of BP on PND 49. In contrast, the weights of female reproductive organs were not affected by BP. The sperm count and the sperm motile activity in the epididymis were significantly decreased at doses of 100 and 200 mg/kg of BP. In accordance with the sperm count in the epididymis, the number of round spermatids and elongated spermatids in the seminiferous tubule (stage VII) were significantly decreased by BP. Testicular expression of estrogen receptor (ER)-alpha and ER-beta mRNA was significantly increased in 200 mg/kg of BP treated group at PND 90. Taken together, these results indicated that maternal exposure of BP might have adverse effects on the F1 male offspring.  (+info)