L. A. Goldblatt

Bio: L. A. Goldblatt is an academic researcher from United States Department of Agriculture. The author has contributed to research in topics: Aflatoxin & Cottonseed. The author has an hindex of 11, co-authored 22 publications receiving 613 citations.

Determination of aflatoxins in individual peanuts and peanut sections

Abstract: Subsamples of a given lot of peanuts may vary greatly in aflatoxin content due to extreme variability in the degree of contamination of individual kernels. A micro method, adapted from the aqueous acetone procedure recently proposed by Pons and Goldblatt for the determination of aflatoxins in cottonseed products, was developed to permit accurate determination of aflatoxins in individual kernels and kernel sections. Use of this procedure permitted the topographic distribution of aflatoxins within single kernels to be mapped and indicated that the toxins are not uniformly distributed within contaminated kernels, even when the kernel contains a high level of aflatoxins. Although wrinkling or discoloration sometimes indicated that a kernel was contaminated, this type of physical damage was not found to be a reliable indication of aflatoxin content. Also it was noted that a few apparently sound and mature kernels contained high levels of aflatoxins.

Objective fluorometric measurement of alfatoxins on TLC plates

Abstract: Measurement of the solid state fluorescence of aflatoxins on silica gel-coated TLC plates on a densitometer equipped for fluorescence measurements showed a linear relationship between peak areas and concentration over a range of at least 2 to 105×10−4 μg of aflatoxins per spot. Response of individual aflatoxins was in order of B2>G2>B1>G1. Aflatoxins can be measured with a precision of ±2–4%.

Control and removal of aflatoxin

Abstract: The best approach to contain the problem of aflatoxin is prevention and enough is now known about prevention to reduce contamination drastically. Guidelines for preventing mycotoxins in farm commodities have been suggested by the U.S. Department of Agriculture. Moisture is the single most important parameter and prompt drying to safe levels is essential for control of toxigenic molds. Foreign matter and damaged seed should be removed. Provision of clean, dry, adequately cooled and ventilated storage is important and good sanitation is essential to minimize mold contamination during storage and processing: Genetic approaches which may result in resistance to elaboration of aflatoxins are under investigation. When aflatoxin is found in a sample of oilseeds the contamination generally resides in only a small proportion of the kernels, commonly less than 1%. Sorting or separation can concentrate the vast majority of aflatoxin-contaminated kernels into relatively small fractions and only a small loss is incurred as a result of their removal. Aflatoxin is frequently found deeply imbedded within individual kernels so removal by simple washing does not seem feasible. However, extraction with polar solvents such as alcohols and ketones to achieve essentially complete removal of aflatoxins appears technically feasible. Heat is relatively ineffective for destruction of aflatoxin although normal roasting, as of peanuts for the preparation of peanut butter, results in considerable reduction in aflatoxin content. Treatment withFlavobacterium aurantiacum removes aflatoxin and may be useful for beverages. Oxidizing agents readily destroy aflatoxin, and treatment with hydrogen peroxide may be useful. Treatment of defatted oilseed meals with ammonia can reduce aflatoxin content to very low or undetectable levels with only moderate damage to protein quality.

Association of official analytical chemists: 1964-1988

Abstract: In 1964, William Horowitz published the history of the Association of Official Agricultural Chemists (AOAC), of which he was the chief executive officer (Horwitz 1964). At that time the AOAC had existed for 80 years and had ventured very little beyond its stated purpose of validating and publishing standardized methods of analysis for substances important to agriculture and the public health through a highly structured system of interlaboratory testing and review. In the ensuing quarter of a century, however, the AOAC not only changed its name to Association of Official Analytical Chemists but also underwent a striking expansion and transformation. The highlights of that transformation are the subject of this account.

Liver microsomal metabolism of aflatoxin B 1 to a reactive derivative toxic to Salmonella typhimurium TA 1530.

Abstract: Summary A reduction in the survival of Salmonella tryphimurium TA 1530 was observed when the bacteria were incubated with aflatoxin B 1 , rat liver microsomes, and a reduced nicotinamide adenine dinucleotide phosphate-generating system. The lethality appeared to depend on the formation of a metabolite of aflatoxin B 1 by a mixed-function oxygenase system. The killing was very rapid; only 1% of the bacteria were able to form colonies after 2 min of incubation with large amounts of microsomes and aflatoxin B 1 . Attempts to separate the toxic metabolite from the microsomal system have not been successful. Toxic metabolites for S. typhimurium TA 1530 were also formed if aflatoxin B 1 was replaced by either aflatoxin G 1 or sterigmatocystin in the microsome-mediated toxicity assay. Except for aflatoxicol, the derivatives that were tested either had much less activity or were inactive. The livers from a number of other species of rodents and a single autopsy sample of human liver also were active in the microsome-mediated aflatoxin B 1 toxicity assay. The addition of RNA or DNA to the incubation mixture inhibited the killing of the bacteria. The RNA (which was reisolated after its incubation with aflatoxin B 1 ), liver microsomes, and a reduced nicotinamide adenine dinucleotide phosphate-generating system showed a low, broad absorption, with a maximum at 366 to 370 nm. This high wavelength absorption was not removed by Sephadex G-10 chromatography of the RNA or by extraction procedures and appeared to be attributable to covalently bound aflatoxin B 1 toxicity assay. The formation of the conjugated RNA was dependent on reduced nicotinamide adenine dinucleotide phosphate and was inhibited by the addition of aniline; the amount formed was a function of the activity of the mixed-function oxygenases in the incubation mixture. On the basis of the data presented, it is tentatively suggested that the derivative that is toxic to S. typhimurium TA 1530 and the one that reacts with nucleic acids are identical. The possible relationship of this derivative to the hepatocarcinogenicity of aflatoxin B 1 is discussed.

Aflatoxins in food: occurrence, biosynthesis, effects on organisms, detection, and methods of control.

Abstract: Aflatoxins are secondary metabolites produced by species of Aspergilli, specifically Aspergillus flavus and Aspergillus parasiticus. These molds are ubiquitous in nature and grow on a variety of substrates, thereby producing aflatoxins. Aflatoxins are of great concern due to their biochemical and biological effects on living organisms. In this article, the occurrence of aflatoxins, their biosynthesis, factors influencing their production, their effects on living organisms, and methods of detection and control in food are reviewed. Future areas of research involving mathematical modeling of factors influencing aflatoxin production and alternative methods of control, such as modified atmosphere packaging, are also discussed.

Comparison of alternative solvents for oils extraction

Abstract: A comprehensive review of the literature about use of solvents for extraction of oilseeds is presented. Mention has been found of over 70 solvents. Currently, hexane is the major solvent in use, but recent price increases and safety, environmental and health concerns, have generated interest in alternatives. Solvents vary considerably in chemical and physical properties which affect their performance in oil extraction. The choice of solvent depends upon the primary end product desired (oil or meal). Recent research on alternative solvents has focused on ethanol, isopropanol, methylene chloride, aqueous acetone, and hexane/acetone/water mixtures.