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L Stoloff

Publications and source records attributed to L Stoloff.

At least 37 records · Page 2Linked to original sources
PubMed1979

Extraction, cleanup, and quantitative determination of aflatoxins B1 ANd M1 in beef liver.

A method for the determination of aflatoxin B1 in eggs was applicable for aflatoxin B1 in liver, but ineffective for aflatoxin M1 in liver because of poor recovery of added aflatoxin and interferences in thin layer chromatography. The method was modified by the addition of citric acid to the extracting solvent and ammonium sulfate to the extract solution for removing protein. The elution system for silica gel column cleanup was also changed by substituting methanol for acetone, and adding a step for confirmation of aflatoxin M1 identity. The method has been used successfully for survey and research on aflatoxin residues in animal tissues.

Aflatoxins↗
PubMed1978

Matthew.

Explore the source record for details and available documents.

Deafness↗
PubMed1978

Survey for aflatoxin B1 in chicken eggs.

Samples of egg products were obtained during January and July 1977 from 35 establishments located in the southern part of the United States. Of the 112 samples analyzed, aflatoxin B1 was found in 1 sample of liquid egg white at a level of 0.06 ng/g. No aflatoxin was found in 101 samples of shell eggs offered for sale to consumers in Alabama, Georgia, South Carolina, and North Carolina in the late fall of 1977.

Aflatoxins↗
PubMed1977

Aflatoxin and zearalenone occurrence in dry-milled corn products.

Eighty-two corn dry-milling establishments in 20 states were surveyed concerning control practices for preventing the use of corn contaminated with aflatoxin or zearalenone. Prime products and by-products from each establishment were analyzed for these mycotoxins to determine whether a correlation exists between control practices and product contamination. No zearalenone was detected in any product; there was little awareness of the potential for contamination with this mycotoxin. No correlation was found between control practices and aflatoxin contamination encountered, but there was a positive correlation between aflatoxin contamination and the geographical source of the corn. Reported experimental findings in regard to the distribution of aflatoxin between prime product and by-product were generally corroborated.

Aflatoxins↗
PubMed1977

Thin layer chromatographic determination of aflatoxin B1 in eggs.

A method for determining aflatoxin in dairy products was modified for eggs, initially by additional cleanup steps. The modified method proved practical for use in survey analyses and was sufficiently sensitive to detect aflatoxin B1 at levels less than 1 ng/g in eggs from hens on experimentally contaminated feed and in spiked eggs; interfering compounds in eggs received from many different producing areas were eliminated. Although recovery was greater than 75% when the aflatoxin was extracted immediately after spiking, recovery was usually less than 30% when the aflatoxin was extracted after more than 24 hr. Adding sodium chloride, sodium sulfate, or urea to the extracting solvent remedied this defect, which is thought to be related to the binding of aflatoxin to egg protein.

Aflatoxins↗
PubMed1976

Survey for aflatoxins and zearalenone in 1973 crop corn stored on farms and in country elevators.

A total of 315 marketable and 57 obviously damaged corn samples were collected at 116 different farms and country elevators located in the United States in countries selected from among those producing more than 1 million bushels of corn in 1972. The samples were analyzed for aflatoxins and zearalenone. The most striking correlations observed were between geographical area and mycotoxin contamination. Aflatoxin contamination was most frequently encountered in the Southeast-Appalachia areas with a 44% incidence of marketable corn with detectable aflatoxins. Zearalenone was most frequently encountered in the Corn Belt with 10% incidence in marketable corn from that region. When mycotoxin contamination was found in an establishment, most of the samples from that establishment were contaminated. There was no correlation between mycotoxin contamination and storage practices nor could the observed contamination of marketable corn be related to the contamination of the obviously damaged grain. These observations plus correlations with the geographic incidence and aflatoxin level distribution of published field contamination data suggest the possibility of a common contamination mode.

Aflatoxins↗
PubMed1976

A review of sampling plans and collaboratively studied methods of analysis for aflatoxins.

Aflatoxins are the only food contaminants being monitored routinely on an international scale with methods operating at the order of magnitude of 10 mug/kg. At this concentration level, methods of analysis which can achieve coefficients of variation of 30-40% with recoveries of 70% or greater in interlaboratory collaborative studies can be considered eligible for referee status. In most cases, sample reproducibility is the variable limiting the reliability of methods of analysis. The inherent uncertainty of the identity of chromatographically separated entities requires the application of confirmatory tests to verify that the characteristic measured results from the presence of aflatoxin. The methods are also inoperable without a verification of the identity, purity, and concentration of the reference standards used. Screening methods which reliably eliminate negative samples from further consideration are indispensible for the practical operation of monitoring programs.

Aflatoxins↗
PubMed1975

Stability of aflatoxin M in milk.

This three-part study was designed to determine aflatoxin M recovery from pasteurized and/or stored cow's milk. (a) Aflatoxin M was added to samples of raw Holstein milk at a concentration of 2.0 mug/liter. Half of each sample then was pasteurized at 63 C for 30 min, and both raw and pasteurized portions were stored at 4 C up to 17 days. (b) Samples of raw milk, pasteurized (77 C, 16 s) skim milk, dry cottage cheese curd, and cottage cheese whey were taken from a commercial operation in an area in which natural contamination had been encountered. (c) Milk from a cow dosed with aflatoxin B1 was stored frozen (-18 C) in bulk and in assay-size sample containers for 120 days. Aflatoxin M was recovered completely after either storage or pasteurization in (a) and (b). In (c), a recovery deficiency was detectable after 68 days of storage, which increased to 45% of the original value by 120 days. These observations differ from those of others in that loss of aflatoxin M was significant after pasteurization or storage of raw milk, totaling 87% loss after 120 days of frozen storage. Aflatoxin M partitioning between curd and whey in the preparation of cottage cheese agrees with more recent studies, but differs from previous reports. Three possible explanations for the differences are offered.

Aflatoxins↗