Raisins and Currants as Conventional Nutraceuticals in Italian Market: Natural Occurrence of Ochratoxin A

Abstract

The healthy consumers make a strong pressure to natural products that can prevent the chronic diseases and improve the general health status, and therefore an important aspect that have to be considered is the safe level of the nutraceuticals. This study reports the occurrence of Ochratoxin A (OTA) and associated fungal contamination in 35 samples of dried vine fruits imported in the European community potentially used for the development of new nutraceutical supplements. High pressure liquid chromatography analysis identified 18 samples as contaminated by OTA with an average level of 2.6 μg/kg. OTA was measured in 4 samples of currants (mean value of 6.6 μg/kg) and 13 samples of raisins (mean value of 1.4 μg/kg). In one sample of currants and one of raisins from Turkey OTA exceeded the limits set by European Commission of 10 μg/kg, being contaminated with 12.61 and 15.99 μg/kg, respectively. All the positive samples were confirmed by Orbitrap Q Exactive through their molecular weight and the corresponding fragmentation. The worldwide consumption of dried vine fruits contributed to OTA exposure in several group of consumers. In particular, considering the potential nutraceutical approach, this consumption may be represent a severe risk for healthy consumers that consider these products like healthy and salutistic for their contents in antioxidants, flavonoids, and polyphenols. Data reported in this study confirmed the need to regularly monitor mycotoxin levels in these food products and optimize the process of fruits drying in order to reduce the development of toxigenic molds.

Genetic Diversity, Ochratoxin A and Fumonisin Profiles of Strains of Aspergillus Section Nigri Isolated from Dried Vine Fruits

“…13 with 10.6 µg/kg; Table 1 ). This finding corresponds well with results of numerous investigations which indicated that, despite the high incidence of OTA in the analysed samples, only a low percentage of the contaminated samples exceeded the maximum tolerable values [ 50 , 52 , 53 , 54 , 55 , 56 ]. Nonetheless, high levels of OTA in dried vine fruits, exceeding the critical threshold value of 10 μg/kg, were documented elsewhere [ 31 , 43 , 51 , 57 , 58 , 59 ].…”

Recent Advances in Mycotoxin Analysis and Detection of Mycotoxigenic Fungi in Grapes and Derived Products

“…Mycotoxin determination becomes technically a demanding issue, if not particularly delicate, when one bears in mind that the legislative permitted levels for these substances in grapes and derived products are on the order of a few parts per billion. Taking as an example OTA reports on grape products, there are reports of up to 10 ng/mL in grapes juices and wines [61,72] or even higher than 10 ng/mL values for dried grape products [51], when the EU maximum permitted levels are at 2 and 10 ng/mL for the two commodities, respectively. Furthermore, it should be taken in consideration that the legislative levels are set principally for the mycotoxin most often and abundantly detected in a certain commodity, and neglect minor levels of other mycotoxins that may be present and could create an additional danger to human health due to synergistic effects and an augmented mycotoxin burden.…”

“…Dried grapes account for, among others, mainly raisins, currants, and golden raisins, with the difference lying in the grape variety of origin: The first one refers to dried grapes as a generalized term, currants are produced more often from dried Black Corinth grapes, and the latter are made with the Sultanina white grapes from the Eastern Mediterranean, also known as Thompson Seedless in the rest of the world [50]. Numerous reports on dried grapes addressed mycotoxins and the relevant producer fungi, with most of them referring to OTA [51,52]. However, other mycotoxins were also studied, such as AFBs [53,54], FBs [55,56], Alternaria spp.…”

Are dietary supplements containing plant-derived ingredients safe microbiologically?

“…They can also cause acute and chronic poisoning, allergies, diseases of the respiratory and digestive systems, and liver damage. Plant-based products have repeatedly been shown to contain moulds which may produce mycotoxins posing a threat to human health (Bugno et al, 2006, Benedict et al, 2016, Rajeshwari and Raveesha, 2016, Fanelli et al, 2017). Bugno et al (2006) tested a total of 91 samples of medicinal plants to determine contamination by potentially toxigenic moulds.…”