PRODUCTION OF AFLATOXIN IN PRE-PACKAGED LUNCHEON MEAT AND CHEESE AT REFRIGERATOR TEMPERATURES1

1971 ◽  
Vol 34 (7) ◽  
pp. 349-351 ◽  
Author(s):  
L. S. Oldham ◽  
F. W. Oehme ◽  
D. C. Kelley
Keyword(s):  
Public Health ◽  
Thin Layer ◽  
Thin Layer Chromatography ◽  
Aspergillus Flavus ◽  
Aflatoxin Production ◽  
Aflatoxin Concentration ◽  
Luncheon Meat ◽  
The Common ◽  
Meat Samples ◽  
Layer Chromatography

Information is lacking on the ability of the common mold contaminant, Aspergillus flavus, to grow and produce aflatoxin in perishable foods at normal refrigerator temperatures. Because of public health interests we investigated the possibility of certain perishable foods contaminated with the mold developing an aflatoxin concentration under conditions of refrigeration. Cheddar cheese and luncheon-meat samples were inoculated with A. flavus ATCC 15517 and were refrigerated for 12 days at 4.4 or 7.2 C or incubated at 25 C for 12 days, Uninoculated cheese and meat samples were handled in the same manner. All samples were quantitatively analyzed by thin-layer chromatography for presence of aflatoxin. All samples; except those inoculated and incubated at 25 C, were negative for aflatoxin production. This indicated the mold would, not produce detectable aflatoxin in the tested foods when kept at normal refrigeration temperatures for 12 days.

EXPERIMENTAL PRODUCTION OF AFLATOXIN ON BRICK CHEESE1

1972 ◽  
Vol 35 (10) ◽  
pp. 585-587 ◽  
Author(s):  
C. N. Shih ◽  
E. H. Marth
Keyword(s):  
Thin Layer ◽  
Thin Layer Chromatography ◽  
Aspergillus Flavus ◽  
Aspergillus Parasiticus ◽  
Solvent System ◽  
Experimental Production ◽  
Mold Growth ◽  
Layer Chromatography ◽  
Plastic Containers ◽  
Chloroform Methanol

Brick cheese was placed in plastic containers and all surfaces except the top were sealed with wax. The top was inoculated with Aspergillus flavus or Aspergillus parasiticus and cheese was incubated in a humid chamber at 7.2, 12.8, and 23.9 C for up to 14 weeks after mold growth was evident. After incubation each cheese was cut horizontally into four layers, each approximately 1 cm thick. Each layer of cheese was extracted with a monophasic-biphasic solvent system (chloroform, methanol, and water). The extract was purified, concentrated, and aflatoxins were measured by thin-layer chromatography and fluorometry. No aflatoxins were produced by either mold at 7.2 C. At 12.8 C, A. parastticus developed aflatoxins B1 and G1 after 1 week of incubation. Aflatoxin produced by this mold persisted through 4 weeks of storage and then was not detectable. Aspergillus flavus did not form aflatoxin at 12.8 C. Both molds produced aflatoxin on cheese at 23.9 C; A. parasiticus did so after 1 week and A. flavus after 14 weeks. In some instances, aflatoxin was found in cheese 4 cm from the surface. It is reasonable to assume that cheese will not become contaminated with aflatoxin if the food is held at or below 7 C.

Detection of Cashew Nut Shells in Coffee, Tea, and Chicory

1974 ◽  
Vol 57 (3) ◽  
pp. 761-762
Author(s):  
Pratima Sengupta ◽  
Asit R Sen ◽  
Nomita Ghoshdastidar ◽  
Bidhan R Roy
Keyword(s):  
Acetic Acid ◽  
Thin Layer ◽  
Thin Layer Chromatography ◽  
Silica Gel ◽  
Ether Extract ◽  
Cashew Nut ◽  
The Common ◽  
Cashew Nut Shell ◽  
Layer Chromatography ◽  
Ground Coffee

Abstract Thin layer chromatography has been investigated for the identification of cashew nut shell, one of the common adulterants in ground coffee, tea, and chicory. The ether extract of the sample is applied to silica gel C plates and developed with benzene-dioxane-acetic acid (90+25+4) . Cashew nut shell shows 3 distinctive spots (Rf 0.7, 0.54, and 0.34) with diazotized benzidine which are totally absent in tea, coffee, and chicory. The spots have been identified as anacardic acid, cardol, and anacardol, respectively.

Simplified Method for Microscale Production and Quantification of Aflatoxin in Broth1

1984 ◽  
Vol 47 (7) ◽  
pp. 526-529 ◽  
Author(s):  
WEI-YUN J. TSAI ◽  
JIMMY D. LAMBERT ◽  
LLOYD B. BULLERMAN
Keyword(s):  
Solvent Extraction ◽  
Thin Layer ◽  
Thin Layer Chromatography ◽  
Frozen Storage ◽  
Aflatoxin Production ◽  
Production Studies ◽  
Simplified Method ◽  
Tlc Plates ◽  
Layer Chromatography ◽  
Yeast Extract Sucrose

A simplified method for aflatoxin production studies is described. The mold was cultured in 4-dram (15 ml) vials containing 5 ml of yeast extract sucrose broth, and aflatoxin levels were determined by direct spotting of the broth on thin layer chromatography (TLC) plates and quantitating by spectrodensitometry. Equivalent levels of aflatoxins were produced in vials as compared to flasks. When compared to conventional TLC after solvent extraction, direct spotting was rapid, economical and statistically equivalent. Heating broth cultures (121°C, 15 s) before TLC improved the release of aflatoxin from mycelial mats. Aflatoxins were unstable in YES broth during 3 months of frozen storage.

scholarly journals The reaction of iodobenzene-p-sulphonyl chloride (pipsyl chloride) with certain amino acids and peptides, and with insulin

1967 ◽  
Vol 102 (3) ◽  
pp. 815-824 ◽  
Author(s):  
J. C. Fletcher
Keyword(s):  
Amino Acids ◽  
Thin Layer ◽  
Acid Hydrolysis ◽  
Thin Layer Chromatography ◽  
Cysteic Acid ◽  
Buffer System ◽  
The Common ◽  
Layer Chromatography ◽  
Derivatives Of

1. A system of separation using buffered Celite columns is described that enables the pipsyl derivatives of most of the common amino acids to be separated. 2. The reaction of pipsyl chloride with several amino acids not included in previous studies has been investigated. In particular, knowledge of the acid-soluble pipsyl derivatives of arginine, histidine, lysine, tyrosine and cysteic acid has been extended. 3. Reproducible factors have been obtained that enable corrections to be applied for the breakdown of pipsylamino acids on acid hydrolysis. 4. The reaction of pipsyl chloride with peptides has been studied under various conditions. 5. The extent of the reaction between pipsyl chloride and insulin depends on the nature of the solvent-buffer system, and under the best conditions so far found is about 75% complete. 6. In an Appendix, the separation of pipsylamino acids by thin-layer chromatography is described.

Susceptibility of Strawberries, Blackberries, and Cherries to Aspergillus Mold Growth and Aflatoxin Production

1982 ◽  
Vol 65 (3) ◽  
pp. 659-664 ◽  
Author(s):  
Gerald C Llewellyn ◽  
Thomas Eadie ◽  
William V Dashek
Keyword(s):  
Acetic Acid ◽  
Thin Layer ◽  
Thin Layer Chromatography ◽  
Mycelial Growth ◽  
Methylene Chloride ◽  
Aflatoxin Production ◽  
Solvent System ◽  
Mold Growth ◽  
Tlc Plates ◽  
Layer Chromatography

Abstract The susceptibility of blackberries, cherries, and strawberries to Aspergillus growth and aflatoxin production has been examined. Three aflatoxigenic isolates of Aspergillus, A. flavus ATCC 15548 and NRRL 3251 as well as A. parasiticus NRRL 2999, were cultured on homogenates of the fruits for 14 days at 28 ± 2°C. Percent mycelial growth and spore infestation were determined each day with a calibrated grid. At day 14 each culture was frozen at –5°C until aflatoxins were extracted with methylene chloride and water. Aflatoxins were separated by thin layer chromatography (TLC) with benzene-methanol-acetic acid (90 + 5 + 5). This extraction and solvent system provided satisfactory separations of the aflatoxins and was free of background interference on the TLC plates. Although all fruits served as substrates for both Aspergillus growth and aflatoxin production, cherries appeared to be a more favorable substrate than did blackberries, and the latter was more favorable than strawberries. Whereas A. flavus produced both B1 and G1 on all substrates, it yielded B2 and G2 only on cherries. Although A. parasiticus NRRL 2999 synthesized B1, B2, G1, and G2 on both blackberries and cherries, no aflatoxins were detected on strawberries. In contrast, A. flavus NRRL 3251 failed to produce detectable levels of aflatoxin on any substrate. All substrates supported both mycelial growth and subsequent sporulation with cherries > blackberries > strawberries.

Aspergillus parasiticus Growth and Aflatoxin Synthesis on Florunner Peanuts Grown in Gypsum-Supplemented Soil

1993 ◽  
Vol 56 (7) ◽  
pp. 593-594 ◽  
Author(s):  
CINDY L. C. REDING ◽  
MARK A. HARRISON ◽  
CRAIG K. KVIEN
Keyword(s):  
Thin Layer ◽  
Thin Layer Chromatography ◽  
Fungal Biomass ◽  
Aspergillus Parasiticus ◽  
Calcium Supplementation ◽  
Fungal Growth ◽  
Growing Season ◽  
Aflatoxin Production ◽  
Layer Chromatography

Five levels of gypsum supplementation (0, 550, 1100, 2200, and 4400 kg ha−1) were applied to peanut fields 35 d after planting. After the growing season, peanuts were harvested, ground, and inoculated with 1 × 107 Aspergillus parasiticus (NRRL 5139) conidia. After 14 d at 25°C, aflatoxin was extracted and quantified by thin-layer chromatography. Fungal growth was assayed using a modified chitin assay. Peanuts from gypsum-supplemented fields at each level of supplementation supported significantly less aflatoxin production when compared to control peanuts (no calcium supplementation). Results from the chitin assay showed a decrease in fungal biomass which correlated with the decreased aflatoxin synthesis.

scholarly journals Efficacy of the Visual, Minicolumn, and Thin Layer Chromatography Methods to Test Farmers Stock Peanuts for Aflatoxin1

1986 ◽  
Vol 13 (2) ◽  
pp. 74-77 ◽  
Author(s):  
T. B. Whitaker ◽  
J. W. Dickens
Keyword(s):  
Thin Layer ◽  
Thin Layer Chromatography ◽  
Computer Models ◽  
Visual Method ◽  
Aflatoxin Concentration ◽  
Layer Chromatography

Abstract This study estimated the efficacy of the visual A. flavus (VAF), minicolumn (MCL), and thin layer chromatography (TLC) methods to detect farmers stock peanuts which contain aflatoxin. Aflatoxin tests on grade samples from each of 2300 lots of farmers stock peanuts was used to estimate the distribution of farmers stock lots according to their aflatoxin concentration (lot distribution). This lot distribution (with an average aflatoxin concentration of 59.5 parts per billion) was incorporated into each of the 3 computer models that simulate the testing of farmers stock peanuts for aflatoxin when the VAF, MCL, and TLC methods are used. The number of lots accepted and the average aflatoxin concentration (AA) in the accepted lots was predicted. Results indicate that when a given percentage of the lots are accepted, lots accepted by the VAF method have less aflatoxin than those lots accepted by either the MCL or TLC methods. When the present visual method was used to test the above lot distribution, 75.8% of the lots tested were accepted and the AA in the accepted and rejected lots were 4.1 and 232.8 parts per billion, respectively.

Performance of the Visual, Minicolumn and TLC Methods in Detecting Aflatoxin in 20 Contaminated Lots of Farmers Stock Peanuts

1984 ◽  
Vol 11 (2) ◽  
pp. 77-83 ◽  
Author(s):  
J. I. Davidson ◽  
J. W. Dickens ◽  
V. Chew ◽  
T. H. Sanders ◽  
C. E. Holaday ◽  
...  
Keyword(s):  
Thin Layer ◽  
Thin Layer Chromatography ◽  
Coefficient Of Variation ◽  
Visual Methods ◽  
Acceptance Level ◽  
Mean Values ◽  
Analytical Results ◽  
Aflatoxin Concentration ◽  
Layer Chromatography ◽  
Standard Grade

Abstract Standard grade samples (16) from each of 20 selected minilots were used to evaluate three methods for detecting minilots of farmers stock peanuts with unacceptable concentrations of aflatoxin. A visual, a minicolumn and a modified thin layer chromatography (TLC) method were used to compare analytical results, variation, and probability of acceptance for minilots having mean aflatoxin concentrations ranging from 8–255 ppb. Mean values obtained by each of the three methods increased linearly with mean aflatoxin concentrations of the minilots and variation for each method as determined by the variance and coefficient of variation (CV) was very large. The CV for all three methods decreased as aflatoxin concentration increased. Overall performances of the three methods were similar in accepting and rejecting these minilots on the basis of the 1.8 kg grade samples. The greatest difference in the three methods occurred at the zero acceptance level where the modified TLC, minicolumn and visual methods rejected 97, 98 and 88%, respectively, of the minilots with more than 60 ppb aflatoxin. At this acceptance level the TLC, minicolumn and visual methods also rejected 55, 50 and 30%, respectively, of the minilots with less than 30 ppb aflatoxin.

scholarly journals Estimation of the total antioxidant potential in the meat samples using thin-layer chromatography

2020 ◽  
Vol 18 (1) ◽  
pp. 50-57
Author(s):  
Paweł Piszcz ◽  
Magdalena Tomaszewska ◽  
Bronisław K. Głód
Keyword(s):  
Thin Layer ◽  
Thin Layer Chromatography ◽  
Antioxidant Properties ◽  
Antioxidant Potential ◽  
Animal Origin ◽  
Antioxidative Properties ◽  
Total Antioxidant ◽  
Meat Samples ◽  
Total Antioxidant Potential ◽  
Layer Chromatography

AbstractThere is limited literature on the antioxidative properties of food of animal origin. Measurements of antioxidative properties are usually performed using the reaction of reduction of colored 2,2-diphenyl-1-picrylhydrazyl (DPPH) radials. Changes of the DPPH color are tracked photometrically. These measurements are interfered by both, the tested samples and reduced DPPH. This study aims to demonstrate the ability to separate different forms of DPPH (DPPH• and DPPH-H) by thin-layer chromatography (TLC). Further, it has been practically applied in the study of the determination of antioxidative properties of the meat samples. It was found that TLC can be used for the separation of different forms of DPPH as well as for measurement of TAP (total antioxidant potential) values related to the DPPH•. The strongest antioxidant properties were observed for pork neck extracted in buffer pH 2 and for smoked salmon fish extracted in acetone, the lowest for veal and turkey fillet extracted in methanol.

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