In vitro oral bioaccessibility and total content of Cu, Fe, Mn and Zn from transgenic (through cp4 EPSPS gene) and nontransgenic precursor/successor soybean seeds

Influence of Dietary Fibre and Protein Fractions on the Trace Element Bioaccessibility of Turnip Tops (Brassica rapa) Growing under Mediterranean Conditions

The objective of this work was to study the influence of three dietary fibre fractions (pectin, gum arabic and cellulose) and three protein fractions (casein, lactalbumin and soy) on the trace element bioaccessibility (Fe, Mn, Ni, Se and Zn) of turnip tops (B. rapa subsp. Rapa) growing under Mediterranean conditions. Then, it aimed to promote the use of this vegetable not only for direct fresh consumption but also as a main ingredient in the development of food mixtures. The results showed that soluble fibre fractions, such as pectin and gum arabic, can enhance the bioaccessibility of trace elements, such as Fe, Mn, Se and Zn. This effect was not proved for cellulose (an insoluble fibre fraction), in which, at best, no bioaccessibility effect was observed. Regarding the protein fractions, with the exception of Se, caseins and lactalbumin had a neutral effect on improving the trace element bioaccessibility. This did not hold true for soy protein, in which a considerable improvement in the bioaccessibility of Fe, Mn, Se and Zn was determined.

In Vitro Assessment of the Physiologically Relevant Oral Bioaccessibility of Metallic Elements in Edible Herbs Using the Unified Bioaccessibility Protocol

In this work, the total content of seven metallic elements (Fe, Cu, Zn, Mg, Pb, Ni, and Co) in common edible herbs was determined and related to their bioaccessibility by an in vitro human digestion model. Specifically, the unified bioaccessibility protocol developed by the BioAccessibility Research Group of Europe (BARGE) was used to determine the release of each element during gastric and gastrointestinal digestion. The results show that Fe, Zn, and Mg are released during gastric digestion (34-57% Fe, 28-80% Zn, 79-95% Mg), but their overall bioaccessibility is reduced in the gastrointestinal tract (<30%). On the contrary, Cu is more bioaccessible during gastrointestinal digestion (38-60%). Pb, Ni, and Co exhibited similar bioaccessibility in both gastric and gastrointestinal fluids. Principle component analysis of the data shows that the classification of the nutritional value of herbs differs between the total and the gastrointestinal concentration, suggesting that the total concentration alone is not an adequate indicator for drawing secure conclusions concerning the nutritional benefits of edible plant species.

Trace Elements in Soy-Based Beverages: A Comprehensive Study of Total Content and In Vitro Bioaccessibility

Soy-based beverages are one of the most consumed plant-based beverages, which have been used as a substitute for dairy products. Soy is a source of several nutrients (vitamins, minerals, and phenolic compounds, etc.) and its consumption is usually associated with several benefits, such as the prevention of cardiovascular diseases, cancer, and osteoporosis. However, non-essential trace elements can be found in these beverages. Thus, a comprehensive study concerning trace elements Al, As, Cd, Co, Cr, Cu, Fe, Li, Mn, Ni, Pb, Sb, Se, Sn, Sr, and Zn in soy-based beverages was proposed. In vitro digestion allowed to simulate the gastrointestinal juice (bioaccessibility) and the Caco-2 cells culture model was applied for the bioavailability assay. Trace elements measures were performed by inductively coupled plasma optical emission spectrometry (ICP OES). Multivariate analysis classified soy-based beverages according to their soy source (isolate protein, hydrosoluble extract, and beans); Al, Cu, Fe, Mn, Sr, Se, and Zn bioaccessible fractions corresponded to approximately 40%-80% of their total content, and soy-based beverages were found to be a good Fe, Se, and Zn source. However, our results showed risk exposure assessment from daily consumption of one glass of soy-based beverage can contribute to 3.5% and 0.9% of Al Provisional Tolerable Weekly Intake (PTWI) for children and adults, respectively.

Mineral and Trace Elements in Nutritious Flours: Total Contents, In Vitro Bioaccessibility and Contribution to Dietary Intake

The consumption of fruits, vegetables, and cereals in the form of flour has been an alternative for the intake of nutrients, currently seen in a society that seeks a healthier diet. Thus, the assessment of total contents and bioaccessibility is important to better understand the actual intake of nutrients or contaminants present in foods. The objective of this study was to determine the total content and estimate the bioaccessible fraction of Cu, Fe, and Zn in nutritious flours by inductively coupled plasma optical emission spectrometry (ICP OES) after microwave acid digestion. Bioaccessibility was assessed using the in vitro method, taking into account the entire gastrointestinal tract (Unified Bioaccessibility Method (UBM)). The following concentration ranges, in μg g^-1, were found: Ca (341-6275), K (2984-13,953), P (476-6110), Na (< 0.39-2995), Fe (1.4-167), Cu (< 0.01-59.6), and Zn (< 0.07-30.3). Principal component analysis (PCA) and hierarchical cluster analysis (HCA) showed a tendency towards the formation of three groups. The bioaccessible fractions for Cu, Fe, and Zn were considered low, ranging from 0.96 to 40% in the gastrointestinal phase and from 4.1 to 100% in the gastric phase.

Physicochemical Characteristics, Microstructure and Health Promoting Properties of Green Banana Flour

This study aimed to investigate the proximate composition, mineral content, functional properties, molecular structure, in vitro starch digestibility, total phenolic content (TPC), total flavonoid content (TFC) and antioxidant activity (DPPH, FRAP) of green banana flour (GBF) cultivars grown in South Africa. With proximate composition, Finger Rose and Pisang Awak had the highest protein (4.33 g/100 g) and fat (0.85 g/100 g) content, respectively. The highest ash content (3.50 g/100 g) occurred with both Grand Naine and FHIA-01 cultivars. Potassium and copper were the most abundant and least minerals, respectively. Pisang Awak cultivar had the highest water absorption capacity (67.11%), while Du Roi had the highest swelling power (0.83 g/g) at 90 °C. Scanning electron microscopy (SEM) images revealed that starch granules from all GBF cultivars were irregular in shape and they had dense surfaces with debris. All the GBF cultivars had similar diffraction patterns with prominent peaks from 15°-24° diffraction angles. The resistant starch (RS) and amylose content of the FHIA-01 cultivar indicates that the GBF has the potential to lower risks of type 2 diabetes and obesity. The highest TPC, TFC and antioxidant activity occurred with the Grande Naine cultivar. Based on their functional characteristics, the Grand Naine and FHIA-01 GBF cultivars could potentially be used as raw materials for bakery products as well as for the fortification of snacks.

Proteomics analysis reveals that foreign cp4-epsps gene regulates the levels of shikimate and branched pathways in genetically modified soybean line H06-698

Although genetically modified (GM) glyphosate-resistant soybeans with cp4-epsps gene have been widely planted all over the world, their proteomic characteristics are not very clear. In this study, the soybean seeds of a GM soybean line H06-698 (H) with cp4-epsps gene and its non-transgenic counterpart Mengdou12 (M), which were collected from two experiment fields in two years and used as 4 sample groups, were analyzed with label-free proteomics technique. A total of 1706 proteins were identified quantitatively by label-free quantification, and a total of 293 proteins were detected as common differential abundance proteins (DAPs, FC is not less than 1.5) both in two groups or more. Functional enrichment analysis of common DAPs identified from four groups, shows that most up-regulated proteins were clustered into stress response, carbon and energy metabolism, and genetic information processing. Further documentary analysis shows that 15 proteins play important roles in shikimate pathways, reactive oxygen species (ROS) and stress response. These results indicated that the change of protein abundance in different samples were affected by various factors, but except shikimate and branched pathways related proteins, only ROS and stress-related proteins were found to be stably regulated by cp4-epsps gene, and no unexpected and safety-related proteins such as antinutritional factors, allergenic proteins, and toxic proteins were found as DAPs. The influence of foreign genes in genetically modified plants is worthy of attention and this work provides new clues for exploring the regulated proteins and pathways in GM plants.

Manganese in the Diet: Bioaccessibility, Adequate Intake, and Neurotoxicological Effects

Manganese (Mn) is an essential element that participates in several biological processes. Mn serves as a cofactor for several enzymes, such as glutamine synthetase and oxidoreductases, that have an important role in the defense of the organisms against oxidative stress. The diet is the main source of Mn intake for humans, and adequate daily intake levels for this metal change with age. Moreover, in higher amounts, Mn may be toxic, mainly to the brain. Here, we provide an overview of Mn occurrence in food, addressing its bioaccessibility and discussing the dietary standard and recommended intake of Mn consumption. In addition, we review some mechanisms underlying Mn-induced neurotoxicity.

Maize cultivars relieve health risks of Cd-Polluted Soils: In vitro Cd bioaccessibility and bioavailability

Dietary grain ingestion is the primary route of human exposure to the adverse effects of Cd; therefore, an understanding of the transfer characteristics of Cd in a system involving soil, grain, and humans is crucial for health risk alleviation and pollution control. In this study, Cd bioaccessibility and bioavailability for humans from grains of sweet maize (Zea mays convar. saccharata var. rugosa) cultivars grown on a contaminated field (1.05 mg Cd kg^-1 soil) were assessed by combining a simulated in vitro digestion method with a Caco-2 cell model. Results showed that cultivars differed significantly in grain Cd concentration, bioaccessibility, and bioavailability with the corresponding values of 0.07 to 0.20 mg kg^-1 DW (dry weight), 4.10 to 6.20%, and 0.01 to 0.04 µg g^-1grain, respectively. The estimated daily intake of Cd through sweet maize grain was within the range of 0.04 and 0.25 μg kg^-1 body weight, which is lower than the tolerable limit recommended by the Joint FAO/WHO Expert Committee on Food Additives (JEFCA). Conclusively, results from the present study indicate that most grain Cd remains non-bioaccessible and thus might not present adverse health effects in humans. Therefore, sweet maize cultivars could be used to produce healthy food crops in low-to-moderately Cd-contaminated soil.

Investigation of a rapid infrared heating assisted mineralization of soybean matrices for trace element analysis

A fast sample preparation procedure based on use of infrared (IR) assisted heating for mineralization of soybean derived samples has been developed for their subsequent multielement analysis by inductively coupled plasma optical emission spectrometry (ICP-OES) and flame atomic absorption spectrometry (FAAS). A cold finger was examined for refluxing of acid vapors to determine its impact on efficiency and economy of digestion. The optimized procedure, based on 1 g subsamples, 8 mL of HNO3 (65% w/w) and exposure of the mixture to a 500 W IR source for 5 min without refluxing, permitted accurate determination of all analytes in NIST SRM 1568b (rice flour). Detection limits using ICP-OES were (µg/kg) 97, 1.0, 39, 185, 0.47 and 1200 for Ca, Cu, Fe, K, Mn and P, respectively, and 18 for Zn by FAAS. The IR-assisted digestion approach provided a low cost, easy to use system having great potential for implementation in routine analysis of trace elements in soybean and similar matrices.

In vitro gastrointestinal digestion to evaluate the total, bioaccessible and bioavailable concentrations of iron and manganese in açaí (Euterpe oleracea Mart.) pulps

Açaí pulp consumption has increased in Brazil and worldwide. Recently, a high average content of manganese (450 mg/kg) was observed in açaí pulp, raising the hypothesis of toxicological effects associated to its ingestion. However, the total concentration of an element does not reflect the real benefits and risks of consuming a food. In this context, the total, bioaccessible and bioavailable concentrations of Fe and Mn were assessed in 9 açaí pulps. Fe and Mn contents ranged from 27.6 to 73 and from 145 to 1197 mg kg^-1, respectively. Fe and Mn bioaccessibilities represented from 29 to 40 and from 39 to 55% of total amounts. Fe bioavailabilities were lower than LOQ and those of Mn varied from 8 to 17% of total. A daily consumption of 100 g of açaí pulp exceeds by at least 1.5-fold the recommended Mn daily intakes for adults whereas poorly contributes to Fe intakes. Since the lowest Mn bioaccessible and bioavailable fraction corresponded to a Mn intake value higher than the tolerable upper intakes for children and that high amounts of Mn intake may impair Fe absorption, higher açaí consumption may be worrisome. Future nutritional, toxicological and speciation studies must be undertaken.

Evaluation of changes in the macro and micronutrients homeostasis of transgenic and non-transgenic soybean plants after cultivation with silver nanoparticles through ionomic approaches

An ionomic approach is conducted for evaluating the silver distribution, in different soybean plant compartments, as well as its influence on the homeostasis of some macro (P and S) and micro (Cu, Fe, Mn and Zn) nutrients. Silver is added to transgenic and non-transgenic soybean plants as nanoparticles or silver nitrate for comparative purposes. The transgenic plants translocate a higher amount of silver (100 and 65% for silver nanoparticles and silver nitrate expositions, respectively) than non-transgenic, and considering the treatments, the cultivation with silver nanoparticles results in a higher translocation rate (100 and 21% for transgenic and non-transgenic plants, respectively). In addition, significant differences are found (p < 0.05) considering those macro and micronutrients in all plant compartments, mainly in the roots of those treated plants, indicating not only that both silver forms evaluated interfere in the plant metabolism, but also their toxicities.

Boosted Electrochemical Immunosensing of Genetically Modified Crop Markers Using Nanobody and Mesoporous Carbon

The problems of environmental security and the potential risks of human health caused by transgenic crops have attracted much attention. Recent studies reveal 5-enolpyruvylshikimate-3-phosphate synthase (EPSPS) from Agrobacterium sp. strain CP4 protein (CP4-EPSPS), which shows very high resistance to herbicide glyphosate, is a typical biomarker of genetically modified (GM) crops. For this reason, it is highly anticipated to devise a sensitive and convenient strategy to detect CP4-EPSPS protein in crops. Herein, we report a simple electrochemical immunosensor by coupling nanobody, ordered mesoporous carbon (OMC), and thionine (Th). As a capture agent, the nanobody was screened out from an immunized Bactrian camel, and exhibited superior properties with respect to conventional antibody, such as higher stability and stronger heat resistance. Moreover, OMC offered an effective platform with high surface area, electrical conductivity, and biocompatibility, which greatly facilitated the assembly of redox probe Th, and further coupling of large amount of capture nanobodies. As a result, the CP4-EPSPS protein could be determined with high sensitivity and efficiency by differential pulse voltammetry (DPV) in a wide linear range from 0.001 to 100 ng·mL^-1 with a low detection limit of 0.72 pg·mL^-1, which was more than 3 orders of magnitude lower than those of previously reported works. As an example, the proposed electrochemical immunosensor was successfully applied to spiked samples, demonstrating its great potential in CP4-EPSPS screening and detection.