Bioaccessibility of Cd, Cu, Fe, Mn, Pb, and Zn in Hazelnut and Walnut Kernels Investigated by an Enzymolysis Approach

Abstract

Bioaccessibility of four essential (Fe, Cu, Mn, Zn) and two toxic (Cd, Pb) elements in kernels of four walnut and four hazelnut cultivars was investigated using sequential enzymolysis approach and atomic absorption spectrometry. It was found that the assimilable part of elements was not dependent on nut cultivar. The bioaccessible fraction of Cu, Mn, and Zn was definitely higher for hazelnuts (62% Cu, 39% Mn, 58% Zn) than for walnuts (14% Cu, 21% Mn, 15% Zn). Bioaccessible Fe was 20-24% from its total content for both nut types. Solubility in the simulated intestinal juice is affected by both formation of stable soluble complexes and back sorption of dissolved elements on nut solid residues. Lead shows strong insolubility due to the high sorption affinity of lead ions to the insoluble fraction of nuts. Thus, walnuts and hazelnuts could act as effective biosorbents for lead detoxication.

Bioaccessibility versus Bioavailability of Essential (Cu, Fe, Mn, and Zn) and Toxic (Pb) Elements from Phyto Hyperaccumulator Pistia stratiotes: Potential Risk of Dietary Intake

“…35,43 Moreover, Pb can also be re-adsorbed on solid residues in chyme. 27 The Pb BAC pattern of control feed in our experiment was in accordance with this presumption. On the contrary, Pb BAC from PS biomass under intestinal conditions was twice as high as that in an artificial stomach environment.…”

“…The main part of Pb in plant material is organically bound in the form of strong complexes (biomacromolecules), which are not dissociated even in a stomach environment. 27 Up to 99% of Pb can be insoluble because of chelation with polyphenols, phytosterols, or di-and monoacylglycerols. 38 When the Pb bioaccessible fractions from PS were compared to those from other biological materials (Table 7), considerably low levels (5−9%) were observed in our experiment.…”

Assessment of the Safe Consumption of Nuts in Terms of the Content of Toxic Elements with Chemometric Analysis

“…Moreover, Cd stress was related to changes in total fatty acids content in all classes [ 28 ]. The in vitro bioaccessibility of Cd from hazelnuts and walnuts was between 26 and 27% in the gastric juice and between 42 and 45% in the intestinal juice [ 29 ]. However, a lower bioavailability of Cd in nuts was determined by Moreda-Piñeiro et al The authors obtained the following results for macadamia nuts (4.4%), pecans (2.2%), hazelnuts (3.5%), peanuts (2.2%), pine nuts (2.3%) and pistachios (1.4%) [ 3 ].…”

Effect of conservation methods on the bioaccessibility of bioelements from in vitro‐digested edible mushrooms

“…nuts, cereals, and leguminous food products (rice, pulses, and cereal groats), it turns out that the bioavailability of bioelements from mushroom material is higher for the majority of analyzed samples, which confirms that mushrooms are a dietetically valuable food. 20,37,38 Chemometric analysis It is possible that a large amount of data generated in our experiments can lead us to the wrong interpretation of the results; we therefore performed chemometric analysis on the sun-dried, dryer-dried, lyophilized, frozen, and fresh samples of three different mushroom species. The objects were described by parametersbioelements analyzed in them (Mg, Zn, Cu, and Fe).…”

“…The daily adult requirement (RDA) for zinc is 11 mg, for iron 8 mg, for copper 0.9 mg, and for magnesium 350 mg, therefore, due to the content in edible mushrooms, they can be their source. 20,21 The evaluation of the release of bioelements and their potential bioavailability therefore seems to be a very important issue. In vivo experiments on bioavailability are the ideal research models involving animals and humans but they are often timeconsuming and expensive; it is therefore important to find a fast and effective in vitro method to assess bioavailability, which will allow us to obtain reliable results, especially in the case of mushrooms.…”