Occurrence of ochratoxin A in black pepper, coriander, ginger and turmeric in India.
Ochratoxin A (OA) contamination of black pepper, coriander seeds, powdered ginger and turmeric powder was estimated using indirect competitive ELISA. Samples (1 g) were extracted with 0.5% potassium chloride (KCl) in 70% methanol (5 ml) and diluted subsequently to give two-fold to ten-fold step-wise dilutions in phosphate-buffered saline containing 0.05% Tween 20 and 0.2% bovine serum albumin (PBS-T BSA). For extracts from the spices analysed, ELISA estimates of OA concentrations were compared with those made by HPLC. All estimates were within 1-2 standard deviation of the ELISA values. More than 90% of OA added to spice samples was recovered from samples containing between 5 and 100 microg/kg OA. Extracts of OA-free spice samples contained substances that interfered with ELISA, presumably because of non-specific reactions. This effect was avoided by preparing all the test solutions in extracts of OA-free spice samples. In 126 samples obtained from retail shops, OA was found to exceed 10 microg/kg in 14 (in the range of 15-69 microg/kg) of 26 black pepper samples, 20 (in the range of 10-51 microg/kg) of 50 coriander samples, two (23 microg/kg and 80 microg/kg) of 25 ginger samples and nine (in the range of 11-102 microg/kg) of 25 turmeric samples. This is the first record in India of the occurrence of OA in what are some of the most widely used spices in Indian cooking.
Thirumala-Devi
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International Crops Research Institute for the Semi-Arid Tropics, Patancheru, Andhra Pradesh, India.
Mayo
M A
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Reddy
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Tangni
E K
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Larondelle
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Reddy
D V
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Emmanuel
K E
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D019661:Apiaceae / Q000737:chemistry; D002273:Carcinogens / Q000032:analysis*; D002851:Chromatography, High Pressure Liquid / Q000379:methods; D003474:Curcumin / Q000737:chemistry; D004797:Enzyme-Linked Immunosorbent Assay / Q000379:methods; D005506:Food Contamination; D020939:Zingiber officinale / Q000737:chemistry; D006801:Humans; D009183:Mycotoxins / Q000032:analysis; D009793:Ochratoxins / Q000032:analysis*; D010946:Plants, Medicinal; D017365:Spices / Q000032:analysis*
D002273:Carcinogens; D009183:Mycotoxins; D009793:Ochratoxins; C025589:ochratoxin A; D003474:Curcumin