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Antarctic seaweeds are vital components of polar marine ecosystems, playing a crucial role in nutrient cycling and supporting diverse life forms. The sulfur content in these organisms is particularly interesting due to its implication in biogeochemical processes and potential impacts on local and global environmental systems. In this study, we present a comprehensive characterization of seaweed collected in the Antarctic in terms of their total sulfur content and its distribution among different classes of species, including thiols, using various methods and high-sensitivity techniques. The data presented in this paper are unprecedented in the scientific literature. These methods allowed for the determination of total sulfur content and the distribution of sulfur compounds in different fractions, such as water-soluble and proteins, as well as the speciation of sulfur compounds in these fractions, providing valuable insights into the chemical composition of these unique marine organisms. Our results revealed that the total sulfur concentration in Antarctic seaweeds varied widely across different species, ranging from 5.5 to 56 g kg−1 dry weight. Furthermore, our investigation into the sulfur speciation revealed the presence of various sulfur compounds, including sulfate, and some thiols, which were quantified in all ten seaweed species evaluated. The concentration of these individual sulfur species also displayed considerable variability among the studied seaweeds. This study provides the first in-depth examination of total sulfur content and sulfur speciation in brown and red Antarctic seaweeds. [ABSTRACT FROM AUTHOR]

This document is a summary of an article titled "Elemental Mass Spectrometry for Bioanalysis" published in the journal Analytical & Bioanalytical Chemistry. The article discusses the importance and versatility of mass spectrometry (MS) as an analytical tool for characterizing matter in living and non-living systems. It focuses on elemental mass spectrometry, which involves degrading matter to its basic components, and highlights the use of inductively coupled plasma mass spectrometry (ICP-MS) as a primary source for elemental ions. The article also covers various applications of elemental mass spectrometry in fields such as environmental monitoring, food control, and biological research. The topical collection in the article includes 24 contributions that reflect current research and trends in elemental mass spectrometry for bioanalysis, covering topics such as sample preparation, elemental speciation, protein analysis, and the detection of small objects like cells and nanoparticles. The guest editors express their appreciation for the contributions and hope that the collection serves as a valuable source for readers. The article is authored by Jörg Bettmer, Mario Corte-Rodríguez, and Marcia Foster Mesko, who are experts in the field of analytical chemistry and have published extensively in this area. [Extracted from the article]

Manganese (Mn) is an essential element that, in excess, seems to be involved in the development of different neurodegenerative conditions. Gamma-oryzanol (Ory) was previously reported to possess antioxidant and neuroprotective properties. Thus, we conducted this study to test the hypothesis that Ory can also protect flies in an Mn intoxication model. Adult wild-type flies were fed over 10 days with Mn (5 mM) and/or Ory (25 μM). Flies treated with Mn had a decrease in locomotor activity and a higher mortality rate compared to those in controls. Mn-treated flies also had a significant increase in acetylcholinesterase (AChE) activity, in Mn accumulation and in oxidative stress markers. Moreover, flies treated with Mn exhibited a significant decrease in dopamine levels and in tyrosine hydroxylase activity, as well as in mitochondrial and cellular viability. Particularly important, Ory protected against mortality and avoided locomotor and biochemical changes associated with Mn exposure. However, Ory did not prevent the accumulation of Mn. The present results support the notion that Ory effectively attenuates detrimental changes associated with Mn exposure in Drosophila melanogaster, reinforcing its neuroprotective action/potential. [ABSTRACT FROM AUTHOR]

A suitable and green analytical method using microwave-induced combustion and ion chromatography with conductivity detection (IC-CD) and mass spectrometry detection (IC-MS) was proposed for the halogens and sulfur determination in pet food using a single analysis. Samples (up to 500 mg) were efficiently digested in a closed system under oxygen pressure (20 bar). Ultrapure water and 50 mmol L−1 or 100 mmol L−1 (NH4)2CO3 were evaluated as absorbing solutions. Trueness was evaluated by recovery tests using standard solution and certified reference materials. In both tests, mean recoveries ranging from 91 to 108% for all analytes were obtained using 50 mmol L−1 (NH4)2CO3 as absorbing solution. AOAC International recommended official methods for Cl and F determination in animal feed were also performed. Results for Cl using proposed method were in agreement with those obtained using AOAC official method, while the results for F were not compared between them because the concentration in the samples using AOAC official method was not detected. Precision was evaluated in terms of repeatability and the relative standard deviations (RSDs) using the proposed method were always lower than 8%. The proposed method presents several advantages when compared with AOAC International official methods such as the multielemental determination capability, lower waste generation, lower limits of detection, lower RSDs, and higher sample throughput. Sixteen samples destined to cats or dogs from different manufacturers were analyzed and the results showed a wide variation. These results indicate that an efficient quality control should be performed, and the proposed method is an excellent alternative as a new analytical tool for routine analysis of pet food. [ABSTRACT FROM AUTHOR]

A single analysis of hair for determining halogens (chlorine, bromine, fluorine, and iodine) and sulfur by ion chromatography with suppressed conductivity and mass spectrometry detection (IC-MS) was proposed. Inductively coupled plasma optical emission spectrometry (ICP OES) and inductively coupled plasma mass spectrometry (ICP-MS) were also used to compare the results. For this purpose, 300 mg of human hair were digested by microwave-induced combustion (MIC) using 20 bar of oxygen pressure. The analytes were absorbed in 100 mmol L−1 NH4OH. Trueness of the proposed method was evaluated by analysis of a CRM of human hair; by recovery tests, using standard solution at two levels (50% and 100%), and by comparison of results with those obtained by ICP OES (Cl and S) and ICP-MS (Br and I). Suitable recoveries (ranging from 92 to 105%) were obtained, and the results from CRM analysis did not differ significantly from those described in the certificate. Moreover, results obtained by IC-MS did not present significant differences (p > 0.05) from those obtained by ICP OES and by ICP-MS. Precision was evaluated in terms of repeatability and intermediate precision, and the relative standard deviations were always lower than 8%. The proposed method presented good accuracy and it is a reliable strategy for human hair analysis. Final digests obtained using the MIC method were fully compatible with all proposed determination techniques. Compared to others reported in the literature, the proposed method presents several advantages, especially given that it is possible to determine halogens and sulfur in a single analysis. [ABSTRACT FROM AUTHOR]