Automated infrared ashing with palladium nitrate as an ashing aid for the determination of selenium in plant foods by inductively coupled plasma mass spectrometry

Based on the automatic light wave ashing instrument, palladium nitrate was used as an ashing aid for the first time to collect selenium in the process of food ashing pre-treatment, and a method for the determination of selenium in food by ashing method was established with inductively coupled plasma mass spectrometry. At the same time, the effects of magnesium nitrate, rhodium nitrate, and nickel nitrate as ashing aids on selenium collection were investigated using certified plant standard materials. The capture of selenium by magnesium nitrate, rhodium nitrate, and nickel nitrate as ashing aids did not exceed 50%. Using palladium nitrate as an ashing aid, six food standard materials were measured, with selenium recovery rates ranging from 97 to 106%. A complete analysis cycle can be completed within an hour. The method detection limit of selenium was 0.021 μg g-1, and the relative standard deviation of five measurements was less than 7%. The experimental results show that palladium nitrate is an excellent ashing aid for capturing selenium, and it is far superior to the other three aids. In addition, the mechanism of palladium nitrate as an ashing aid for capturing selenium was discussed.

Ionomic Approaches for Discovery of Novel Stress-Resilient Genes in Plants

Plants, being sessile, face an array of biotic and abiotic stresses in their lifespan that endanger their survival. Hence, optimized uptake of mineral nutrients creates potential new routes for enhancing plant health and stress resilience. Recently, minerals (both essential and non-essential) have been identified as key players in plant stress biology, owing to their multifaceted functions. However, a realistic understanding of the relationship between different ions and stresses is lacking. In this context, ionomics will provide new platforms for not only understanding the function of the plant ionome during stresses but also identifying the genes and regulatory pathways related to mineral accumulation, transportation, and involvement in different molecular mechanisms under normal or stress conditions. This article provides a general overview of ionomics and the integration of high-throughput ionomic approaches with other "omics" tools. Integrated omics analysis is highly suitable for identification of the genes for various traits that confer biotic and abiotic stress tolerance. Moreover, ionomics advances being used to identify loci using qualitative trait loci and genome-wide association analysis of element uptake and transport within plant tissues, as well as genetic variation within species, are discussed. Furthermore, recent developments in ionomics for the discovery of stress-tolerant genes in plants have also been addressed; these can be used to produce more robust crops with a high nutritional value for sustainable agriculture.

Organic Selenium as Antioxidant Additive in Mitigating Acrylamide in Coffee Beans Roasted via Conventional and Superheated Steam

Selenium is an essential micronutrient with significant antioxidant activity promising in mitigating the formation of acrylamide during high-temperature roasting. In this study, green coffee beans pretreated with selenium (Se-coffee) were investigated on their selenium uptake, selenium retention in green and roasted beans, antioxidant activities, and formation of acrylamide during conventional and superheated steam roasting. Comparisons were made with positive (pretreated without selenium) and negative (untreated) controls. The acrylamide formation was significantly inhibited in Se-coffee (108.9-165.3 μg/kg) compared to the positive and negative controls by 73.9% and 52.8%, respectively. The reduction of acrylamide by superheated steam roasting only observed in the untreated coffee beans (negative control) by 32.4% parallel to the increase in its antioxidant activity. Selenium pretreatment significantly increased antioxidant activity of the roasted Se-coffee beans after roasting although soaking pretreatment significantly reduced antioxidant activity in the green beans. Acrylamide reduction in the roasted coffee beans strongly correlated with the change in antioxidant capacities after roasting (∆FRAP, 0.858; ∆DPPH, 0.836). The results indicate that the antioxidant properties of the organic selenium suppressed acrylamide formation during coffee roasting.

Radiochemical neutron activation analysis for the determination of selenium in Mentha spicata L. samples collected from Djelfa, Algeria region

Selenium (Se) has been a focus of attention as an important micronutrient with its impact on human health, with there being consequences either due to excess or deficiency in intake. Radiochemical neutron activation analysis (RNAA) is well established method for determination of a number of elements at trace level concentrations with high sensitivities. In this work, we used the RNAA method for determination of selenium content in Mentha spicata L. The result of this study was compared with those samples from India and Serbia. The result obtained show that, Se concentration obtained in M. spicata L., is close to the minimal FAO recommendation.

Neutron activation analysis of major and trace elements in Arabica and Robusta coffee beans samples consumed in Algeria

The Algerian neutron activation analysis laboratory is highly involved in nutrition applications in the framework of research activities using the Es-Salam research reactor. The main objective of this work is to contribute, by using nuclear analytical techniques, for studying a large number of natural food samples consumed in Algeria related to nutrition and human health. The present study focuses on the analysis of the most popular beans consumed worldwide, namely, the coffee species of Arabica and Robusta, based on the international markets. Chemical content of samples was assessed by instrumental neutron activation analysis (INAA) and k 0-INAA techniques, through the irradiation of samples during 6 h at a thermal neutron flux of 4.5×1013cm−2s−1 of Es-Salam research reactor. A total of 17 elements were assessed such as, (Br, Ca, Ce, Co, Cr, Cs, Fe, K, La, Na, Rb, Sc, Sm, Sr, Zn, Lu and Th) obtained by using INAA and k 0-INAA methods, While we used the radiochemical neutron activation analysis (RNAA and k 0-RNAA) to determine Selenium at low level concentrations, the accuracy of the method was evaluated by analyzing CRM and SRM. QC/QA was evaluated by using the statistical parameter U-score. Results were compared with those obtained for samples from Brazilian, Caribbean, Indian and Kenyan coffee beans reported in the literature. The daily intake of essentials and toxic elements was determined and compared with the recommended values. The probable cumulative intake of toxic elements was found to be well below the tolerance limits.