https://cyberleninka.org/article/n/132565.pdf

Discovery and resupply of pharmacologically active plant-derived natural products: A review.

Switchgrass (Panicum virgatum L.)—a perennial, warm-season (C4) species—evolved across North America into multiple, divergent populations. The resulting natural variation within the species presents considerable morphological diversity and a wide range of adaptation. The species was adopted as a crop—initially as a forage—only in the last 50 yr. Its potential uses have recently been expanded to include biofuels. Management of switchgrass for biofuels is informed by an understanding of the plant's biology. Successful establishment requires attention to seed dormancy and weed control as well as proper depth and date of planting. The plant's growth rate is closely tied to temperature, but timing of reproductive development is linked to photoperiod. Accordingly, the period of vegetative growth can be extended by planting lower-latitude cultivars at higher latitudes. This strategy may provide a yield advantage, but cold tolerance can become limiting. Switchgrass is thrifty in its use of applied N; it appears a...

The Biology and Agronomy of Switchgrass for Biofuels

ContextThe recent discoveries of ricin, a deadly biologic toxin, at a South Carolina postal facility, a White House mail facility, and a US senator’s office has raised concerns among public health officials, physicians, and citizens. Ricin is one of the most potent and lethal substances known, particularly when inhaled. The ease with which the native plant (Ricinus communis) can be obtained and the toxin extracted makes ricin an attractive weapon.ObjectivesTo summarize the literature on ricin poisoning and provide recommendations based on our best professional judgment for clinicians and public health officials that are faced with deliberate release of ricin into the environment.Literature AcquisitionUsing PubMed, we searched MEDLINE and OLDMEDLINE databases (January 1950-August 2005). The Chemical and Biological Information Analysis Center database was searched for historical and military literature related to ricin toxicity. Book chapters, unpublished reports, monographs, relevant news reports, and Web material were also reviewed to find nonindexed articles.ResultsMost literature on ricin poisoning involves castor bean ingestion and experimental animal research. Aerosol release of ricin into the environment or adulteration of food and beverages are pathways to exposure likely to be exploited. Symptoms after ingestion (onset within 12 hours) are nonspecific and may include nausea, vomiting, diarrhea, and abdominal pain and may progress to hypotension, liver failure, renal dysfunction, and death due to multiorgan failure or cardiovascular collapse. Inhalation (onset of symptoms is likely within 8 hours) of ricin is expected to produce cough, dyspnea, arthralgias, and fever and may progress to respiratory distress and death, with few other organ system manifestations. Biological analytic methods for detecting ricin exposure are undergoing investigation and may soon be available through reference laboratories. Testing of environmental samples is available through federal reference laboratories. Currently, no antidote, vaccine, or other specific effective therapy is available for ricin poisoning or prevention. Prompt treatment with supportive care is necessary to limit morbidity and mortality.ConclusionHealth care workers and public health officials should consider ricin poisoning in patients with gastrointestinal or respiratory tract illness in the setting a credible threat. Poison control centers and public health authorities should be notified of any known illness associated with ricin exposure.

https://jamanetwork.com/journals/jama/articlepdf/201818/jcr50010.pdf

Ricin poisoning: a comprehensive review

https://zenodo.org/record/1004771/files/Cushnie%20et%20al%20%282014%29%20post-peer%20reviewed%20version.pdf

Alkaloids: an overview of their antibacterial, antibiotic-enhancing and antivirulence activities.

The Omnivore's Dilemma: A Natural History of Four Meals

The alkaloid profiles of Sophora nuttalliana and Sophora stenophylla

Plant secondary metabolites (PSM) may increase the sustainability of agriculture systems by reducing inputs, as PSM protect plants against herbivores and pathogens, act as pesticides, insecticides, and anthelmintics while also attracting pollinators and seed dispersers. Therefore, it is important to understand what affects PSM fluctuation in plant tissues. Limited research has investigated how different nitrogen (N) sources affect PSM concentration in alfalfa (Medicago sativa L., Alf), birdsfoot trefoil (Lotus corniculatus L., BFT), reed canarygrass (Phalaris arundinacea L., RCG), and endophyte-infected tall fescue (Festuca arundinacea Schreb., E+TF). We investigated how fecal manure (feces) and synthetic N fertilizer (urea, 46% H₂NCONH₂) influence N concentrations and the PSM ergovaline, gramine, saponins, and extractable condensed tannins (CT) in E+TF, RCG, Alf, and BFT, respectively. Ergovaline, saponins, and CT were not affected by fertilization. Gramine tended (P = 0.06) to be greater in control plots than in fertilized plots. Total N in E+TF and RCG was greater (P < 0.05) and tended to be greater for Alf (P = 0.08) in synthetically fertilized plots than in unfertilized plots. Seasonal variation in PSM and N was significant (P < 0.003) across all species and was species specific. Total N in E+TF was greatest in June (41.4 g kg⁻¹), while ergovaline contents were at the lowest values recorded (117.2 μg kg⁻¹), with subsequent increases to the greatest ergovaline values observed in July (680.0 μg kg⁻¹). Our results reveal the variability in PSM production by plants and highlight the complexities of predicting fluctuations of PSM in forages. As environments where plants grow vary through space and time, we recommend studies on a case-by-case basis, depending on land management objectives.

Plant Secondary Metabolites in Alfalfa, Birdsfoot Trefoil, Reed Canarygrass, and Tall Fescue Unaffected by Two Different Nitrogen Sources

Brachiaria (signalgrass) is now the most widely used tropical grass genus in Central and South America. However, Brachiaria spp. can cause hepatogenous photosensitization in livestock. Steroidal saponins, specifically protodioscin, present in Brachiaria spp. may be responsible for liver injury and subsequent photosensitization. The objective of this study was to determine the effect of ensiling Brachiaria decumbens and Brachiaria brizantha or making hay from Brachiaria decumbens on the concentrations of steroidal saponin in these grasses. Brachiaria grass had no detectable levels of the saponin protodioscin after 24 days of ensiling. In addition, in Brachiaria decumbens, the concentration of the protodioscin decreased 48% over the first three days after haymaking and then remained constant. These results suggest that livestock consuming Brachiaria either as silage or hay may have reduced risk of intoxication by protodioscin.

/pdf/the-effect-of-ensiling-and-haymaking-on-the-concentrations-3u31oyq9ja.pdf

The effect of ensiling and haymaking on the concentrations of steroidal saponin in two Brachiaria grass species.

Plant-associated toxins can be synthesized by the plant, produced by associated microorganisms, or simply incorporated and accumulated by the plant. These toxins are found in nearly all plants, many of which are generally considered “safe” to use as feed and food. Some are potent carcinogens. Others only cause mild inconvenience, such as tainted milk or replacement and loss of other desirable forages. Toxin concentrations and subsequent plant toxicity also vary between plants and even within populations, and between seasons and years. This variation in some situations is related to environmental conditions, but often the cause is unknown. This variation makes it difficult to predict toxicity and subsequent risk of poisoning. Most intoxications affect grazing livestock and wildlife; however, human and companion animal poisoning also occurs. This is generally due to plant or toxin contamination of prepared feeds, food, medicines, and herbal products. The objectives of this chapter are to introduce some common toxic plants and describe some of the pathologic changes relating to their poisoning in animals and humans, with a focus on livestock intoxication.

Stephen T. Lee

Papers

The alkaloid profiles of Sophora nuttalliana and Sophora stenophylla

Plant Secondary Metabolites in Alfalfa, Birdsfoot Trefoil, Reed Canarygrass, and Tall Fescue Unaffected by Two Different Nitrogen Sources

The effect of ensiling and haymaking on the concentrations of steroidal saponin in two Brachiaria grass species.

Selected Poisonous Plants Affecting Animal and Human Health

Allergy skin tests upon castorbean-sensitive humans and passively sensitized cynomolgus monkeys.