Effect of two different roasting techniques on the Ochratoxin A (OTA) reduction in coffee beans (Coffea arabica)

Abstract This study developed and validated a method for measuring concentrations of ochratoxin A (OTA) in coffee beverages, not coffee beans. The new method involved extraction using immunoaffinity columns and ultra-performance LC (UPLC)-MS/MS using isotope-dilution techniques. The combination of a fused-core column and UPLC significantly shortened chromatographic time to 3 min compared to reported UPLC methods. The method was sensitive, with an LOD and LOQ of 0.52 and 1.73 pg/mL, respectively. Quantitative intraday (n = 4) and interday (n = 4) biases and RSD were both below 15%. The OTA levels in 40 samples of freshly brewed coffee from chain stores, 24 samples of canned ready-to-drink coffee, and 6 beverages made from instant coffee granules ranged from 1.60 to 93.2 pg/mL (90% positive), 6.00 to 131 pg/mL (100% positive), and 21.8 to 59.0 pg/mL (100% positive), respectively. Based on published tolerable daily intake, men and women in Taiwan should consume no more than 6.3 and 5.1 fifteen gram packages of instant coffee per day, respectively. Specific suggestions were not made for brewed coffee and canned coffee because of their large variation in OTA concentrations. This study should be more relevant to actual human exposure than those studying OTA in green, roasted, and ground coffee beans alone.

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Genetic relationships among Brazilian strains of Aspergillus ochraceus based on RAPD and ITS sequences

Canadian Journal of Microbiology ◽

10.1139/w04-093 ◽

2004 ◽

Vol 50 (11) ◽

pp. 985-988 ◽

Cited By ~ 9

Author(s):

Maria Helena Pelegrinelli Fungaro ◽

Marciane Magnani ◽

Laurival Antônio Vilas-Boas ◽

Patrícia Cristina Vissotto ◽

Márcia Cristina Furlaneto ◽

...

Keyword(s):

Ochratoxin A ◽

Sequence Data ◽

Genetic Relationships ◽

Its Region ◽

Aspergillus Ochraceus ◽

Coffee Bean ◽

Coffee Beans ◽

Major Species ◽

Group A ◽

Group B

Ochratoxin A (OA) is a mycotoxin that has been found in coffee beans and coffee beverages. Its toxicological profile includes carcinogenicity, nephrotoxicity, and immunotoxicity. Aspergillus ochraceus is the major species responsible for OA production in Brazilian coffee beans. The genetic relationships among 25 A. ochraceus strains collected from Brazilian coffee-bean samples were determined based on RAPD and internal transcribed spacer (ITS) sequence data. The isolates were resolved into 2 distinct groups, one with 4 strains (group A) and the other with 21 strains (group B). Specific nucleotide variations characterizing group A and B were found for both ITS1 and ITS2 regions. Group B is a new group proposed here to accommodate the majority of the Brazilian isolates. Each group was found to contain both toxigenic and nontoxigenic strains, indicating that there is no association between molecular genotypes and the ability to produce OA.Key words: Aspergillus ochraceus, ochratoxin A, ITS region (ITS1–5.8S–ITS2), RAPD.

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Antioxidant Properties Research of Various Types of Coffee

Food Industry ◽

10.29141/2500-1922-2020-5-4-11 ◽

2020 ◽

Vol 5 (4) ◽

pp. 74-81

Author(s):

Dinara Ignatova ◽

Nadezhda Makarova

Keyword(s):

Coffea Arabica ◽

Antioxidant Properties ◽

Reducing Power ◽

Coffea Canephora ◽

Raw Material ◽

Antioxidant Compounds ◽

Common Source ◽

Coffee Arabica ◽

Coffee Beans ◽

Dpph Method

The article presents results of antioxidant compounds determination (total amount of phenolic compounds, total amount of flavonoids) and parameters of the antiradical activity (by the DPPH method) and reducing power (by the FRAP method) in different types of coffee beans depending on roasting degree (weak, medium, strong), coffee variety (Robusta and Arabica) and the importing country. The researchers used the products presented in the retail chains of Samara. The study purpose was to reveal a universal and most common source of functional substances with an antioxidant effect for the human body and use it both in its pure form and in combination with other products (BAS). According to the research results, Robusta coffee (Coffea Canephora) of medium roasting from Brazil has high indicators for all the conducted analyses and can be used as an additional source of antioxidant substances, and as a raw material for obtaining BAS. Coffee Arabica (Coffea Arabica) of medium roasting of Indonesian origin has the highest restoring power, and the highest content of phenols and flavonoids. Coffee Arabica (Coffea Arabica) of a strong degree of roasting from India has the lowest rates. All other types of coffee have average, slightly different results.

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Agrobacterium-mediated insertional mutagenesis of the ochratoxigenic fungus Aspergillus westerdijkiae

Canadian Journal of Microbiology ◽

10.1139/w06-100 ◽

2007 ◽

Vol 53 (1) ◽

pp. 148-151 ◽

Cited By ~ 6

Author(s):

Marcia M Mata ◽

Marta H Taniwaki ◽

Beatriz T Iamanaka ◽

Daniele Sartori ◽

André L.M Oliveira ◽

...

Keyword(s):

Ochratoxin A ◽

Insertional Mutagenesis ◽

Aspergillus Ochraceus ◽

Agrobacterium Mediated Transformation ◽

Morphological Variations ◽

Carcinogenic Potential ◽

Coffee Beans ◽

Aspergillus Westerdijkiae ◽

Polymerase Chain ◽

First Time

Aspergillus westerdijkiae is a potent ochratoxin A (OTA) producer that has been found in coffee beans. OTA is known to have nephrotoxic effects and carcinogenic potential in animal species. Here we report for the first time the Agrobacterium-mediated transformation for Aspergillus westerdijkiae and the generation of ochratoxin-defective mutants. Conidia were transformed to hygromycin B resistance using strain AGL-1 of Agrobacterium tumefaciens. The obtained transformation frequency was up to 47 transformants per 106 target conidia. Among 600 transformants, approximately 5% showed morphological variations. Eight transformants with consistently reduced OTA production were obtained. Two of these transformants did not produce OTA (detection limit: 0.1 µg/kg); the other six mutants produced lower amounts of OTA (1%–32%) compared with the wild-type strain. By using thermal asymmetric interlaced polymerase chain reaction, we successfully identified a putative flavin adenine dinucleotide monooxygenase gene.Key words: Aspergillus ochraceus, Aspergillus westerdijkiae, Agrobacterium-mediated transformation, Agrobacterium-mediated insertional mutagenesis, ochratoxin A.

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Collaborative Study of a Method for the Determination of Ochratoxin A in Green Coffee

Journal of AOAC INTERNATIONAL ◽

10.1093/jaoac/58.2.258 ◽

1975 ◽

Vol 58 (2) ◽

pp. 258-262 ◽

Cited By ~ 2

Author(s):

Colette P Levi

Keyword(s):

Thin Layer ◽

Ochratoxin A ◽

Collaborative Study ◽

Green Coffee ◽

Average Recovery ◽

Semiquantitative Determination ◽

Chromatographic Methods ◽

Green Coffee Beans ◽

Coffee Beans

Abstract A method for the semiquantitative determination of ochratoxin A in green coffee has been studied collaboratively by 11 laboratories. The average recovery for the 7 samples spiked at 3 levels of ochratoxin A was 69.1%, ranging from 60.5 to 85.6%. This is comparable to other visual thin layer chromatographic methods of mycotoxin detection. The method has been adopted as official first action for the determination of ochratoxin A in green coffee beans.

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Ochratoxins A and B, Xanthomegnin, Viomellein and Vioxanthin Production by Isolates of Aspergillus ochraceus from Green Coffee Beans

Journal of Food Protection ◽

10.4315/0362-028x-46.11.965 ◽

1983 ◽

Vol 46 (11) ◽

pp. 965-968 ◽

Cited By ~ 13

Author(s):

MICHAEL E. STACK ◽

PHILIP B. MISLIVEC ◽

TURGUT DENIZEL ◽

REGINA GIBSON ◽

ALBERT E. POHLAND

Keyword(s):

High Performance Liquid Chromatography ◽

Liquid Chromatography ◽

Ochratoxin A ◽

High Performance ◽

Toxin Production ◽

Aspergillus Ochraceus ◽

Average Level ◽

Green Coffee ◽

Green Coffee Beans ◽

Coffee Beans

Isolates from Aspergillus ochraceus obtained from green coffee beans were cultured on rice and water. After 20 d of growth the cultures were extracted with chloroform and the extracts were analyzed by high performance liquid chromatography for ochratoxin A (OA), ochratoxin B (OB), xanthomegnin (X), viomellein (V) and vioxanthin (VX). Forty-three percent of the isolates produced OA at an average level of 397 μg of toxin/g rice, 17% produced OB at an average level of 312 μg/g, and 84% produced X, V, and VX at an average level of 281, 417 and 386 μg/g, respectively. The highest levels of toxin production were OA, 2088 μg/g; OB, 3375 μg/g; X, 1562 μg/g; V, 2514 μg/g; and VX, 2054 μg/g. VX has not previously been reported as an A. ochraceus metabolite.

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