Development and application of LC/MS based analysis for marine algal toxins in Hood Canal

Harmful algal toxins have been well recognized as public health threats (James et al., 2010; Van Dolah, 2000), and a multitude of measures to prevent harmful algal blooms (HABs) derived health risks have been proposed and implemented (Trainer and Hardy, 2015). Coastal communities such as the Skokomish Indian Tribe, consuming a large amount of shellfish to meet their dietary needs are particularly vulnerable to such risks. Washington Department of Health (DOH) has been monitoring marine algal toxins in Puget Sound including coastal areas by collecting shellfish samples followed by mouse-based toxin analysis. To address on-going and future marine algal toxin issues in Hood Canal in the face of changing climate, the Skokomish Indian Tribe launched a research project to develop chemical analysis protocols for representative toxins using LC/MS and monitor algal bloom events. Eight toxins were selected for method development and monitoring Protocols for solid phase extraction combined with LC/MS analysis were developed. Multiple reaction monitoring (MRM) protocols for individual toxin compounds were developed and used to quantify toxin concentrations against standard curves established using certified toxin standard materials. From June through September 2017, we conducted weekly monitoring of algal toxin concentrations in sea water and phytoplankton samples from 13 monitoring sites, including Sequim Bay. No okadaic acid and dinophysistoxin-2 were detected throughout the sampling period, while a few alga toxin compounds were fluctuating over time. The details of spatial and temporal distributions of selected algal toxins in Hood Canal obtained from Summer of 2017 will be presented with a discussion about future directions for this initiative. The newly developed algal toxin analysis using LC/MS offers a promising tool to address some of public health and environmental issues associated with marine algal toxins in Hood Canal as well as possibly in the Salish Sea

Mechanistic investigations of the reactions of nickel and iron complexes. Part I. Reactions of pyramidal Ni(Tim)-complexes. Part II. Reactions of aquapentacyanoferrate(II) and their importance to the environment

With the intention of creating a five-coordinate nickel thiolate complex which could serve as a structural model for the Factor 430-coenzyme M complex, the synthesis of 2, 3, 9, 10-tetramethyl-1, 4, 8, 11-tertaaza-1, 3, 8, 10-cyclotetradecatetraene-nickel(II)-thiolate complexes have allowed for the discovery of an unusual deprotonation reaction leading to a novel macrocyclic product. Kinetic investigations of this reaction lead to a proposed mechanism implicating tautomerization in the rate determining step. A primary isotope effect of $\sim$6 is observed when the protons involved in tautomerization are substituted by deuterium. Labeling the positions involved in deprotonation also exhibits an effect on the reaction rates, however this effect is smaller and assigned to largely secondary isotope effects. The analysis of temperature dependence on the reaction rates gave activation parameters of: $\Delta$H$\ddagger$ = 47.1 kJ/mol, $\Delta$S$\ddagger$ = $-$197 J/mol, $\Delta$G$\ddagger$ = 105.7 kJ/mol. An unusual solvent dependence is observed and may be explained by the formation of solvent adducts. Support for this notion involves the serendipitous crystallization of a six-coordinate methanol adduct. The formation of solvent adducts is expected to affect the displacement of the metal out of the N\sb4-plane of the macrocycle. The degree of displacement may explain the solution state paramagnetism of the complexes, and is expected to influence the reaction rates. Kinetic studies of the decomposition of aquapentacyanoferrate(II), intending to probe the oxidation of this complex, have shown that the rate of oxidation to be accelerated by catalytic amounts of iron(II), manganese(II) and lead(II) ions. A synergistic effect on the reaction rate was noted for a mixture of Pb\sp{+2} and Fe\sp{+2}. By allowing the system to react under simulated environmental conditions, biphasic behavior was noted in the decomposition of the complex as a result of KFe\sp{\rm (II)} (Fe\sp{\rm (III)}(CN)\sb6\rbrack\cdotxH\sb2O (Prussian Blue) formation. A speculative mechanism for the decomposition of aquapentacyanoferrate(II) is proposed, based on the results of this work. The release of cyanide as a consequence of the formation of Prussian Blue is discussed

Stone Magnolias

Volume: 53Start Page: 3End Page:

Molecular Analysis: A New Look at Umbrella Magnolias

Volume: 57Start Page: 22End Page: 2

Major clades and a revised classification of Magnolia and Magnoliaceae based on whole plastid genome sequences via genome skimming

With more than 300 species, the Magnoliaceae family represents a major Magnoliid lineage that is disjunctly distributed in Asia and the New World. The classification of Magnolia s.l. has been highly controversial among taxonomists, varying from one genus with several subgenera, sections, and subsections to several (up to 16) genera. We conducted a comprehensive phylogenetic study of Magnoliaceae on the basis of sequences of the complete chloroplast genomes with a broad taxon sampling of 86 species. The phylogenetic analyses strongly support 15 major clades within Magnolia s.l. due to the non-monophyly of subgen. Magnolia, the previous subgeneric treatment that recognizes three subgenera, is not supported. Based on the phylogenetic, morphological, and geographic evidence, we recognize two subfamilies in Magnoliaceae: Liriodendroideae and Magnolioideae, each with one genus, Liriodendron and Magnolia, respectively. Magnolia is herein classified into 15 sections: sects. Magnolia, Manglietia, Michelia, Gwillimia, Gynopodium, Kmeria, Maingola, Oyama, Rytidospermum, Splendentes, Talauma, Tuliparia, Macrophylla, Tulipastrum, and Yulania