Jennifer M. Duringer

Ecdysteroids from Vitex species: distribution and compilation of their 13C-NMR spectral data.

Iridoids and ecdysteroids are found in some genera of the family Verbenaceae. In such cases, they are used as chemotaxonomic markers for the difficult task of taxonomic identification by using morphological characteristics of plants belonging to this family. The present work describes the distribution of ecdysteroids in plants from the genus Vitex from a review of previous work on seventeen Vitex species. In addition, 13C‐NMR data of the main ecdysteroids found in this genus are described. This study attempted to summarize previous research on ecdysteroids distribution in Vitex species with the addition of 13C‐NMR analysis to further refine the characterization of these compounds in the Verbenaceae family.

Cases of ergotism in livestock and associated ergot alkaloid concentrations in feed

Ergot-induced disease in humans was known long before Biblical times and has been the root cause for countless human epidemics spanning from the early fourteenth century to the late sixteenth century. In contrast, many of these same ergot alkaloids have been utilized for their medicinal properties to mitigate migraine headaches and have had indications as anti-carcinogens. Although ergot alkaloids have been used for centuries by humans, basic pharmacokinetic data has not been documented for clinical disease in livestock. Consequently, a threshold dose and accurate dose-response data have yet to be established. Throughout the past several years, new detection techniques have emerged to detect these alkaloids at the parts per billion (ppb) level which has allowed for new efforts to be made with respect to determining threshold levels and making accurate clinical diagnoses in affected animals. This perspectives article provides a critical initial step for establishing a uniform interpretation of ergot toxicosis from limited existing data.

Uptake and transformation of soil [14C]-trinitrotoluene by cool-season grasses.

This study investigated the fate and uptake of [(14)C]-TNT from soil into orchardgrass (Dactylis glomerata), perennial ryegrass (Lolium perenne), and tall fescue (Festuca arundinacea) over a one year period in a greenhouse-controlled environment. Pots (n = 4 for each grass, containing 10 mg cold TNT/kg soil + 1.2 mg [(14)C]-TNT/kg soil and controls with no TNT) were exposed to light and temperature conditions typical of June at 45 degrees N for 369 days. Three plant harvests were made (63, 181, and 369 days), and soil and plant materials were monitored for [(14)C]-TNT and metabolite concentrations. The 11.2 mg/kg TNT dose was not phytotoxic to the plant species tested. Continual uptake of TNT into grass blades was observed over the one-year period, with a total accumulation of 1.3%, 0.9%, and 0.8% of the initial soil [(14)C]-TNT dose for orchard grass, perennial ryegrass, and tall fescue, respectively. All [(14)C]-TNT residue in plant material was incorporated as bound residue. At final harvest, radioactivity was concentrated most highly in the root > crown > blade for all species. Soil TNT was gradually reduced to aminodinitro-toluenes and then further to an unidentified metabolite(s). Overall, orchardgrass appeared to be the most efficient species at taking up TNT.

Metagenomic Insights into the RDX-Degrading Potential of the Ovine Rumen Microbiome

The manufacturing processes of royal demolition explosive (RDX), or hexahydro-1,3,5-trinitro-1,3,5-triazine, have resulted in serious water contamination. As a potential carcinogen, RDX can cause a broad range of harmful effects to humans and animals. The ovine rumen is capable of rapid degradation of nitroaromatic compounds, including RDX. While ruminal RDX-degrading bacteria have been identified, the genes and pathways responsible for RDX degradation in the rumen have yet to be characterized. In this study, we characterized the metabolic potential of the ovine rumen using metagenomic approaches. Sequences homologous to at least five RDX-degrading genes cloned from environmental samples (diaA, xenA, xenB, xplA, and xplB) were present in the ovine rumen microbiome. Among them, diaA was the most abundant, likely reflective of the predominance of the genus Clostridium in the ovine rumen. At least ten genera known to harbor RDX-degrading microorganisms were detectable. Metagenomic sequences were also annotated using public databases, such as Pfam, COG, and KEGG. Five of the six Pfam protein families known to be responsible for RDX degradation in environmental samples were identified in the ovine rumen. However, increased substrate availability did not appear to enhance the proliferation of RDX-degrading bacteria and alter the microbial composition of the ovine rumen. This implies that the RDX-degrading capacity of the ovine rumen microbiome is likely regulated at the transcription level. Our results provide metagenomic insights into the RDX-degrading potential of the ovine rumen, and they will facilitate the development of novel and economic bioremediation strategies.

ESI-Mass spectrometric and HPLC elucidation of a new ergot alkaloid from perennial ryegrass hay silage associated with bovine reproductive problems

This case report involves four dairies in the Willamette Valley, Oregon, which experienced reproductive problems associated with the presence of a large, previously unidentified, peak eluting at 5 min in a standard ergovaline high-performance liquid chromatography assay of perennial ryegrass silage fed to those animals. Mycotoxin analysis of the silage was negative, as was serological screening of the herds for infectious bovine rhinotracheitis, bovine diarrhea virus and Leptospirosis, including culturing of urine for Leptospira hardjo hardjobovis. Prolactin concentrations were low in most cattle, consistent with ingestion of ergot alkaloids. We believe that this peak represents a novel ergot alkaloid-related compound due to its extractability with Ergosil, its detectability due to fluorescence, and its chromatographic retention between ergovaline (mw = 533) and ergotamine (mw = 581). Its molecular weight was calculated as 570 owing to the predominance of a m/z 593.5 ion in the full scan ESI(+)MS and its deduced tendency to complex with Na+ (as m/z 593) or K+ (as m/z 609) ions. We offer rationales for elucidation of the structure of this compound, with the closest starting point comprising an m.w. of 566—a fructofuranosyl-(2-1)-O-beta-D-fructofuranoside derivative of 6,7-secoergoline from Claviceps fusiformis. This m.w. requires modifications, such as reduction of two double bonds in the secoergoline component to give the target 570 m.w. Despite the lack of a definitive structure, the analysis herein provides a starting point for eventual elucidation of this apparently new ergot alkaloid, and to guide and encourage further investigation as to its association with endophyte toxicosis in livestock.

No Association between Mycotoxin Exposure and Autism: A Pilot Case-Control Study in School-Aged Children

Evaluation of environmental risk factors in the development of autism spectrum disorder (ASD) is needed for a more complete understanding of disease etiology and best approaches for prevention, diagnosis, and treatment. A pilot experiment in 54 children (n = 25 ASD, n = 29 controls; aged 12.4 ± 3.9 years) screened for 87 urinary mycotoxins via liquid chromatography-tandem mass spectrometry to assess current exposure. Zearalenone, zearalenone-4-glucoside, 3-acetyldeoxynivalenol, and altenuene were detected in 9/54 (20%) samples, most near the limit of detection. No mycotoxin/group of mycotoxins was associated with ASD-diagnosed children. To identify potential correlates of mycotoxin presence in urine, we further compared the nine subjects where a urinary mycotoxin was confirmed to the remaining 45 participants and found no difference based on the presence or absence of mycotoxin for age (t-test; p = 0.322), gender (Fisher’s exact test; p = 0.456), exposure or not to selective serotonin reuptake inhibitors (Fisher’s exact test; p = 0.367), or to other medications (Fisher’s exact test; p = 1.00). While no positive association was found, more sophisticated sample preparation techniques and instrumentation, coupled with selectivity for a smaller group of mycotoxins, could improve sensitivity and detection. Further, broadening sampling to in utero (mothers) and newborn-toddler years would cover additional exposure windows.

Endophyte Mycotoxins in Animal Health

Fescue toxicosis and perennial ryegrass staggers are two of the most common toxic plant diseases plaguing livestock in the United States, and result from consumption of forage containing the endophyte-produced mycotoxins ergovaline and lysergic acid (fescue toxicosis) and lolitrem B (ryegrass staggers). Our group has developed analytical assays for detecting these compounds, which serve a dual purpose (1) high-performance liquid chromatography-fluorescence assays are used to measure these compounds in feed material in order to promote “safe feed” through diagnostic testing in a service laboratory environment, and (2) highly sensitive and specific liquid chromatography-tandem mass spectrometry assays are utilized to study the fate and metabolism of these compounds in a diversity of livestock matrices so that a more refined understanding as to the etiology of the diseases these compounds cause can be achieved. A discussion applying these techniques to both current and anticipated studies is given, with an emphasis on impacts to trade and food safety regulation.

Phytochemistry and acute toxicity from the roots of Lippia alba.

Lippia alba (Mill.) N.E. Brown (Verbenaceae), also known as Lippia geminata HBK or Lantana alba (Mill.), is a shrub about 3 m tall. In Brazilian traditional medicine, it is commonly known as Erva-Cidreira, Chá do Tabuleiro, and Salsa Limão. The present work was conducted in order to compare the phytochemistry of the roots and leaves and to determine the acute toxicity of the aqueous extracts from the roots of L. alba. The main components in the leaf extract were citral, β-citral, carvone, hemimelitene, germacrene D, and d-limonene. The main components in the root extract were durene, carvone, patchoulane and hemimellitene. To our knowledge, this is the first report of a phytochemical analysis of the root extract from Lippia alba. The LD50 for the aqueous root extract was calculated to be 1156.25 mgkg−1. The animals presented stimulant and depressive behaviors, showing moderate toxicity, most likely due to the presence of iridoids and phenylpropanoids.

Preliminary Phytochemical Profile and Characterization of the Extract from the Fruits of Xylopia frutescens Aubl. (Annonaceae)

Abstract The chemical composition of essential oils extracted from Xylopia frutescens Aubl. (Annonaceae) fruit (collected in Pernambuco, Brazil) was examined by TLC and GC/MS. TLC analysis detected compounds from the flavonoid and terpenoid groups. GC/MS detected 23 terpenoid compounds, in which the principal components were germacrene D (24.2%), linalool (12.1%), β-pinene (8.0%), cis-sabinene hydrate (7.9%), trans-pinocarveol (7.8%), α-copaene (7.0%) and limonene (5.6%). Other constituents found were sabinene, m-cymene, 1,8-cineole, β-ocimene, perillene, cis-sabinol, α-campholenal, isopinocamphone, terpinen-4-ol, verbenone, trans-carveol, carvone, perillyl alcohol, α-cubebene, β-cadinene and elemol. Most of these compounds have not been detected in fruit extracts of X frutescens before; therefore this study represents the most comprehensive analysis to date of the chemical components in the fruits of this plant.

Survival and development of potato psyllid (Hemiptera: Triozidae) on Convolvulaceae: Effects of a plant-fungus symbiosis (Periglandula)

Plant species in the family Solanaceae are the usual hosts of potato psyllid, Bactericera cockerelli (Šulc) (Hemiptera: Psylloidea: Triozidae). However, the psyllid has also been shown to develop on some species of Convolvulaceae (bindweeds and morning glories). Developmental success on Convolvulaceae is surprising given the rarity of psyllid species worldwide associated with this plant family. We assayed 14 species of Convolvulaceae across four genera (Convolvulus, Calystegia, Ipomoea, Turbina) to identify species that allow development of potato psyllid. Two populations of psyllids were assayed (Texas, Washington). The Texas population overlaps extensively with native Convolvulaceae, whereas Washington State is noticeably lacking in Convolvulaceae. Results of assays were overlain on a phylogenetic analysis of plant species to examine whether Convolvulaceae distantly related to the typical host (potato) were less likely to allow development than species of Convolvulaceae more closely related. Survival was independent of psyllid population and location of the plant species on our phylogenetic tree. We then examined whether presence of a fungal symbiont of Convolvulaceae (Periglandula spp.) affected psyllid survival. These fungi associate with Convolvulaceae and produce a class of mycotoxins (ergot alkaloids) that may confer protection against plant-feeding arthropods. Periglandula was found in 11 of our 14 species, including in two genera (Convolvulus, Calystegia) not previously known to host the symbiont. Of these 11 species, leaf tissues from five contained large quantities of two classes of ergot alkaloids (clavines, amides of lysergic acid) when evaluated by LC-MS/MS. All five species also harbored Periglandula. No ergot alkaloids were detected in species free of the fungal symbiont. Potato psyllid rapidly died on the five species that harbored Periglandula and contained ergot alkaloids, but survived to adulthood on seven of the nine species in which ergot alkaloids were not detected. These results support the hypothesis that a plant-fungus symbiotic relationship affects the suitability of certain Convolvulaceae to potato psyllid.