Fate of Aflatoxin B1 during the Cooking of Korean Polished Rice

2005 ◽  
Vol 68 (7) ◽  
pp. 1431-1434 ◽  
Author(s):  
JE WON PARK ◽  
CHAN LEE ◽  
YOUNG-BAE KIM

The fate of aflatoxin B1 (AFB1), a mycotoxin known to occur in polished rice, during rice cooking was evaluated to determine reduction in AFB1 residues and mutagenic potentials. The amounts of AFB1 in three lots of naturally contaminated polished rice from Korea were analyzed by high-performance liquid chromatography after washing and after steaming. An in vitro mutagenicity assay with Salmonella Typhimurium TA100 was used to confirm the results of the chemical analyses. Cooking significantly reduced AFB1 (mean reduction, 34%) in naturally contaminated polished rice and reduced mutagenicity by ca. 27%. Processing factors (reflecting the removal of AFB1 residues during processing) for cooked rice were estimated at 0.66 to 0.73, as determined chemically and toxicologically, respectively. The revised Korean provisional daily intake of AFB1 from consumption of rice as a dietary staple (0.58 to 3.94 ng/kg of body weight per day) is still higher than that reported for foods in general in the United States (0.26 ng/kg of body weight per day). Thus, Koreans probably consume higher amounts of foodborne AFB1 than do Americans and thus are at higher risk for AFB1-induced health consequences.

2005 ◽  
Vol 68 (10) ◽  
pp. 2107-2111 ◽  
Author(s):  
JE WON PARK ◽  
SOO-HYUN CHUNG ◽  
CHAN LEE ◽  
YOUNG-BAE KIM

Ochratoxin A (OTA), a mycotoxin widespread in cereals, occurs in polished rice that is consumed as cooked rice after washing and steaming. Cooking decreases OTA levels in food to varying extents, but little is known about how cooking changes the biological activity of this mycotoxin. We therefore evaluated the fate of OTA during rice cooking to determine the OTA residues and cytotoxic potential in vitro. Water-washed rice, ordinary cooked rice, and pressure-cooked rice were prepared from three polished rice lots naturally contaminated with OTA. Residual OTA in each sample was analyzed by high-performance liquid chromatography (HPLC), whereas in vitro cytotoxicity of OTA to C6 glioma cells, susceptible to low levels (nanograms per milliliter) of OTA, was used to confirm the chemical analysis. OTA concentration, as determined by HPLC analysis, in the cooked rice by both types of cookers was significantly lower than (59 to 75%) in the raw polished rice and water-washed rice. The cytotoxicity of the OTA that remained in the pressure-cooked rice from three lots was markedly decreased (approximately 20%, P < 0.05) when compared with other samples in respective lots. This confirms that cooking lowers OTA residues. Although washing polished rice with water had little effect on OTA levels, pressure steaming appeared to be the critical cooking step not only to reduce OTA residues in polished rice before reaching the consumer as the dietary staple of cooked rice, but also to diminish cytotoxicity of OTA.


2011 ◽  
Vol 1 (1) ◽  
pp. 4 ◽  
Author(s):  
Hansen W. Murcia ◽  
Gonzalo J. Díaz ◽  
Sandra Milena Cepeda

Cytochrome P450 enzymes (CYP) are a group of monooxygenases able to biotransform several kinds of xenobiotics including aflatoxin B1 (AFB1), a highly toxic mycotoxin. These enzymes have been widely studied in humans and others mammals, but there is not enough information in commercial poultry species about their biochemical characteristics or substrate specificity. The aim of the present study was to identify CYPs from avian liver microsomes with the use of prototype substrates specific for human CYP enzymes and AFB1. Biochemical characterization was carried out in vitro and biotransformation products were detected by high-performance liquid chromatography (HPLC). Enzymatic constants were calculated and comparisons between turkey, duck, quail and chicken activities were done. The results demonstrate the presence of four avian ortholog enzyme activities possibly related with a CYP1A1, CYP1A2, CYP2A6 (activity not previously identified) and CYP3A4 poultry orthologs, respectively. Large differences in enzyme kinetics specific for prototype substrates were found among the poultry species studied. Turkey liver microsomes had the highest affinity and catalytic rate for AFB1 whereas chicken enzymes had the lowest affinity and catalytic rate for the same substrate. Quail and duck microsomes showed intermediate values. These results correlate well with the known in vivo sensitivity for AFB1 except for the duck. A high correlation coefficient between 7-ethoxyresorufin-Odeethylase (EROD) and 7-methoxyresorufin- O-deethylase (MROD) activities was found in the four poultry species, suggesting that these two enzymatic activities might be carried out by the same enzyme. The results of the present study indicate that four prototype enzyme activities are present in poultry liver microsomes, possibly related with the presence of three CYP avian orthologs. More studies are needed in order to further characterize these enzymes.


2019 ◽  
Vol 97 (Supplement_3) ◽  
pp. 273-274
Author(s):  
Patricia M Oba ◽  
Nagait Hwisa ◽  
Xinhe Huang ◽  
Keith Cadwallader ◽  
Kelly S Swanson

Abstract Exposing ingredients to high temperatures may result in chemical reactions between amino acids and sugars, leading to the formation of Maillard reaction products (MRPs). These products may result in altered palatability, protein quality, and digestibility. This experiment quantified key MRPs in commercial pet foods, estimated daily intake of MRPs of pet animals, and correlated MRPs with macronutrient concentrations present in the foods. The analysis included 53 pet foods and treats commercially available in the United States: 11 dry dog foods, 29 wet dog foods, 2 dry dog treats, 3 wet dog treats, 2 dry cat foods, and 6 wet cat foods. Diets and treats were analyzed for dry matter, organic matter, crude protein (CP), acid-hydrolyzed fat, total dietary fiber, and gross energy using standard techniques. MRPs were analyzed using high-performance liquid chromatography and gas chromatography-mass spectrometry. All data were analyzed as a completely randomized design using the GLM procedure of SAS 9.4. On average, wet foods had higher (P < 0.001) fructoselysine (FRUC) and carboxymethyllysine (CML) than dry foods. Dry dog treats had the highest (P < 0.001) FRUC (29.64 µg/g) and CML (0.47 mg/g) concentrations of all products tested. Dry cat foods had the lowest (P < 0.001) CML (0.10 mg/g) concentrations of all commercial segments. Wet dog treats had the highest (P < 0.001) 5-hydroxymethyl-2-furfural (HMF) (10.92 µg/g) concentrations of all segments and wet cat foods had the lowest (P < 0.001) HMF (0.22 µg/g) content. Dogs and cats fed wet diets would be more likely to ingest higher amounts of CML and FRUC compared to animals fed dry diets. Dogs consuming dry treats would be more likely to ingest higher amounts of CML than wet treats. CP was negatively correlated to HMF (P = 0.0425; r = -0.27973), while TSF was positively correlated to CML (P = 0.0417; r = 0.28080).


2020 ◽  
Vol 154 (5) ◽  
pp. 627-634
Author(s):  
Nicola J Rutherford-Parker ◽  
Sean T Campbell ◽  
Jennifer M Colby ◽  
Zahra Shajani-Yi

Abstract Objectives Voxelotor was recently approved for use in the United States as a treatment for sickle cell disease (SCD) and has been shown to interfere with the quantitation of hemoglobin (Hb) S percentage. This study aimed to determine the effect of voxelotor on the quantitation of hemoglobin variant levels in patients with multiple SCD genotypes. Methods In vitro experiments were performed to assess the impact of voxelotor treatment on hemoglobin variant testing. Whole blood samples were incubated with voxelotor and then analyzed by routinely used quantitative and qualitative clinical laboratory methods (high-performance liquid chromatography [HPLC], capillary zone electrophoresis [CZE], and acid and alkaline electrophoresis). Results Voxelotor modified the α-globin chain of multiple hemoglobins, including HbA, HbS, HbC, HbD-Punjab, HbE, HbA2, and HbF. These voxelotor-hemoglobin complexes prevented accurate quantitation of multiple hemoglobin species, including HbS, by HPLC and CZE. Conclusions Technical limitations in quantifying HbS percentage may preclude the use of HPLC or CZE for monitoring patients treated with voxelotor. Furthermore, it is unclear whether HbS-voxelotor complexes are clinically equivalent to HbS. Consensus guidelines for reporting hemoglobin variant percentages for patients taking voxelotor are needed, as these values are necessary for determining the number of RBC units to exchange in acute situations.


2015 ◽  
Vol 78 (3) ◽  
pp. 561-566 ◽  
Author(s):  
MAYUMI HACHINOHE ◽  
TOMOYA OKUNISHI ◽  
SHOJI HAGIWARA ◽  
SETSUKO TODORIKI ◽  
SHINICHI KAWAMOTO ◽  
...  

We investigated the distribution of cesium-134 (134Cs) and cesium-137 (137Cs) during polishing and cooking of rice to obtain their processing factors (Pf) and food processing retention factors (Fr) to make the information available for an adequate understanding of radioactive Cs dynamics. Polishing brown rice resulted in a decreased radioactive Cs concentration of the polished rice, but the bran and germ (outer layers) exhibited higher concentrations than brown rice. The Pf values for 100% polished rice and outer layers ranged from 0.47 to 0.48 and 6.5 to 7.8, respectively. The Fr values for 100% polished rice and outer layers were 0.43 and 0.58 to 0.60, respectively. The distribution of radioactive Cs in polished rice and outer layers was estimated at approximately 40 and 60%, respectively. On the other hand, cooked rice showed significantly lower levels of radioactive Cs than polished rice, and transfer of radioactive Cs into wash water was observed. The Pf and Fr values for cooked rice were 0.28 and 0.65 to 0.66, respectively. From these results, we can calculate that if the radioactive Cs concentration in brown rice is 100 Bq/kg, the concentrations of Cs in polished rice and cooked rice will be 47 to 48 Bq/kg and 13 Bq/kg, respectively.


2018 ◽  
Vol 81 (4) ◽  
pp. 670-676 ◽  
Author(s):  
MOHAMMAD HADI AAZAMI ◽  
MOHAMMAD HASAN FATHI NASRI ◽  
MOHSEN MOJTAHEDI ◽  
SHAHLA ROUDBAR MOHAMMADI

ABSTRACT The aim of this study was to evaluate the ability of heat-killed baker's yeast (HKBY), the cell wall of baker's yeast (CWBY), and cell wall (1→3)-β-d-glucan of baker's yeast (BGBY) to bind aflatoxin B1 (AFB1) in phosphate-buffered saline (PBS) spiked with 0.5 μg/mL AFB1. Baker's yeast (Saccharomyces cerevisiae) was heat killed by autoclaving at 121°C for 10 min. The cell wall was physically extracted, and (1→3)-β-d-glucan was extracted by a modified method. The concentration of AFB1 was determined by high-performance liquid chromatography after exposure to binders for three contact times, 30 min, 5 h, and 24 h, at room temperature. AFB1 binding by HKBY, CWBY, and BGBY was 6.30 to 46.34%. The lowest binding capacity was found for HKBY with a contact time of 30 min, and the highest binding capacity was found for BGBY with a contact time of 24 h. Among binders, CWBY had the highest binder-AFB1 complex stability during washing with PBS, and the lowest stability was found for HKBY complexes. Results of this study indicated that BGBY was the most effective binder, and more exposure to BGBY removes more AFB1 from PBS.


2021 ◽  
pp. 1-12
Author(s):  
S.B. Boni ◽  
F. Beed ◽  
M.E. Kimanya ◽  
E. Koyano ◽  
O. Mponda ◽  
...  

Aflatoxins are toxic and carcinogenic secondary metabolites, produced by Aspergillus flavus and Aspergillus parasiticus, which contaminate food and feed and threaten human and animal health. To assess the prevalence of aflatoxins in Tanzania, 180 groundnut and 200 maize samples were collected from 9 and 10 districts, respectively. Aflatoxin contamination was quantified using high performance liquid chromatography. Aflatoxins were detected in samples collected from all districts and prevalence ranged from 92 to 100% for groundnuts and 10 to 80% for maize. The mean aflatoxin level for groundnuts was 6.37 μg/kg and the highly contaminated sample had 40.31 μg/kg. For maize, the mean aflatoxin level was 12.47 μg/kg and the highly contaminated sample had 162.40 μg/kg. The estimated average probable daily intake (APDI) of aflatoxin B1 (AFB1) from groundnuts consumption was 1.88 ng/kg body weight/day, while for maize, it ranged between 151.98-272.89 ng/kg body weight/day. The APDI for both groundnut and maize exceeded the provisional maximum tolerable daily intake (PMTDI) of AFB1 for adults (1 ng/kg body weight/day), bringing about health concerns for populations in Tanzania. Another alarming finding was that 75% of the farmers who provided samples for analysis were not aware of aflatoxins or the negative health impacts from consuming contaminated products. Results reported in this paper show that aflatoxin contaminated staple crops are widely distributed in Tanzania and that the risk of human exposure is high due to diet preferences. Awareness campaigns are required to inform and protect farmers and consumers.


Author(s):  
GAMIL Q. OTHMAN ◽  
YASER M. AL-WORAFI ◽  
MOHAMMED M. BATTAH ◽  
ABDULSALAM M. HALBOUP ◽  
HASSAN M. HASSAN

Objective: The objective of the current study was to evaluate the quality control parameters of seven brands of levofloxacin 500 mg film-coated tablet available in the Yemeni market. Methods: Physicochemical parameters assay was performed for seven brands of levofloxacin 500 mg film-coated tablet. Each brand was subjected to official and unofficial in vitro quality control tests, including weight variation, thickness, hardness, friability, disintegration, dissolution, and content uniformity assay by High-Performance Liquid Chromatography (HPLC). Results: Out of seven, six brands of levofloxacin 500 mg film-coated tablet passed official specified assay tests according to the United States Pharmacopeia (USP) specifications. They showed a similar profile of thickness ranged between±0.01 and 0.10%, friability ranged between 0.01% and 0.34%, disintegration time ranged between 3.00 and 15.00 min, dissolution percentage ranged between 90.650 and 103.05 and content uniformity ranged between 93.62 and 107.12%. Regarding weight variation and hardness, six brands passed the weight variation test and only three brands showed optimum range (10-20 kg) of hardness test. Only one brand failed to pass the weight variation test, and four brands failed to pass the optimum range (10-20 kg) of hardness. Conclusion: There are no remarkable differences between the seven brands regarding in vitro quality control tests of content uniformity, thickness, friability, disintegration, and dissolution. Even though four brands were above the optimum range of hardiness, they showed complete disintegration and dissolution within the acceptable limit. Regular assessment of marketed drugs is required to ensure bioequivalent to their innovators.


Author(s):  
S. Lasram ◽  
Z. Hamdi ◽  
A. Ghorbel

Background: Ochratoxin A (OTA) and Aflatoxin B1 (AFB1) are toxic secondary  metabolites produced by certain mold species. In this primarily survey, we examined the OTA and AFB1 contamination of pearl millet grains distributed in Tunisia. Methods: Twenty-five pearl millet (Pennisetum glaucum L.) samples from different regions of Tunisia were analyzed by High Performance Liquid Chromatography coupled with fluorescence detector in order to evaluate the contamination with of AFB1 and OTA. Statistical tests were performed with XLSTAT 2018. Results: AFB1 and OTA were detected in 32 and 28% millet samples, respectively. Mean amounts of these mycotoxins in the contaminated samples were of 24.54±17.54 µg/kg for OTA and 22.72±23.09 µg/kg for AFB1. Approximately, 28 and 24% of analyzed samples were found above the European Union limits for AFB1 and OTA, respectively. The estimated daily intake of OTA and AFB1 were 3.76 and 3.89 ng/kg b.w. per day, respectively. No significantly (p>0.05) difference in OTA and AFB1 contamination rate was found between samples taken from different regions. Conclusion: Consumption of millet in Tunisia might be an important contributing factor to the risk of dietary exposure to OTA and AFB1


2020 ◽  
Vol 103 (5) ◽  
pp. 1378-1393
Author(s):  
Bharathi Avula ◽  
Satyanarayanaraju Sagi ◽  
Mubashir H Masoodi ◽  
Ji-Yeong Bae ◽  
Adil F Wali ◽  
...  

Abstract Background Propolis is a resinous substance produced by bees. Propolis extracts have been used for anti-inflammatory and antimicrobial activities. The use of propolis dietary supplements has been increasing in the United States and the rest of the world. Objective A simple, economic, and valid analytical method is needed for quality assessment of dietary supplements and extracts claiming to contain propolis. Methods A ultra-high performance liquid chromatography (UHPLC) quadropole time-of-flight-MS method was used to characterize the chemical composition of northern Indian propolis. Fourteen major phenolic compounds were quantified using a UHPLC-DAD method. An HPTLC method was used to develop chemical fingerprinting profiles for propolis extracts and dietary supplements. The seven propolis extracts and 14 dietary supplements purchased in the U.S. were analyzed using the UHPLC-DAD-QToF method. Results Fifty-seven compounds belonging to phenolic, coumarin, fatty acid, and terpene classes were identified in propolis extracts. Based on quantification results, the content of 14 phenolic compounds in propolis extracts varied from 19–32% in dietary supplements, a significant variation to the recommended daily intake (0.2–94 mg/day). Conclusions/Highlights The developed analytical methods can be used for quality assessment of propolis extracts and dietary supplements.


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