Toxic natural products

Other Lethal Agents. There are a number of substances, many found in nature, which are known to be more toxic than nerve agents (6). None has been weaponized. Examples of these toxic natural products include shellfish poison, isolated from toxic clams puffer fish poison, isolated from the viscera of the puffer fish the active principle of curare "heart poisons" of the digitaUs type the active principle of the sea cucumber active principles of snake venom and the protein ricin, obtained from castor beans (See Castor oil). 

Effect of Rotenone and Antimycin A on Electron Transfer Rotenone, a toxic natural product from plants, strongly inhibits NADH dehydrogenase of insect and fish mitochondria. Antimycin A, a toxic antibiotic, strongly inhibits the oxidation of ubiquinol. 

What does the following reaction show about toxic natural products ... 

Gerwick, W. H., Proteau, P. J., Nagle, D. G., Hamel, E., Blokhin, A., and Slate, D. L., Structure of curacin A, a novel antimitotic, antiproliferative, and brine shrimp toxic natural product from the marine cyanobacterium Lyngbya majuscula, J. Org. Chem., 59, 1243, 1994. 

Solenopsis ants produce piperidine alkaloids which resemble the plant alkaloid coniine. These alkaloids are strong deterrents and inhibit several cellular processes, such as electron transport chains (Table IV) 28,494). Many insects indicate the content of toxic natural products by warning colors (aposematism) or by the production of malodorous pyrazines 4,17,231,494). 

A Papua New Guinea eolleetion of the marine cyanobacterium Lyngbya majuscula yielded two new toxic natural products, hermitamides A 89 and B 90. Hermitamides 89 and 90 exhibited LD50 values of 5 pM and 18 pM, respectively, in the brine shrimp (Artemia salina) bioactivity experiment, and IC50 values of 2.2 pM and 5.5 pM to Neuro-2a neuroblastoma cells in tissue culture. Hermitamide A was mildly ichthyotoxic to goldfish, with an LD50 value of 19 pM, while hermitamide B was inactive at 25 pM. 

Contents indude metabolic processes, microbial processes, biodegradation and bioaccumulation, aquatic and soil biochemistry, organometallics, inorganic and organic toxic compounds, and toxic natural products. 

The fargefs for natural biological toxins include ion channels and receptors for transmitfers. At least four parts of fhe volfage-gafed sodium charmels are binding sifes for extremely toxic natural products. " Tetrodotoxin (Fig. 30-16), which is found in the puffer fish, certain newts, and venom of fhe blue-ringed octopus, and also the shellfish poison saxitoxin (Fig. 

In conclusion, of the two basic resistance-conferring biochemical phenomena encountered in many other producers of secreted self-toxic natural products, elimination of inhibitory action and export of inhibitor, only the first one seems to be verified in the producers of ACAGAs. In these organisms, suppression of antibiotic action can be achieved either via inactivation of the toxic agent by group transfer or by modification of... 

The story told by the dead king, of being murdered by his brother using hebona juice, leaves an indelible picture in the mind. Perhaps the reason for this is that the story was so well and succinctly told, or it may have been that the use of a natural product as a weapon made the story more horrible. The latter explanation may account for the success of the modern murder mystery. We are used to its victims being dispatched with a variety of natural poisons from curare-tipped darts to tetrodotoxin-poisoned meals. Compounds such as curare and tetrodotox-in are toxic natural products of wide diversity and have many curious structures, chemically speaking. However, these compounds, which are extracted from leaves or puffer fish, are not included in the present survey. More commonplace exam-... 

Natural products, including herbal products derived from naturcd products, are exempt from regulation as food additives by the FDA because the chemiccds they contain occur naturally and have not been added by people. However, the majority of toxic chemicals we eat (including many that can cause cancer) occur naturally in our food. In fact, many toxic natural products are much more potent than any of the food additives that have ever been used. Yet media coverage of chemicals in food usually focuses on chemicals that have been added to food. The natural chemicals present in foods often only make the news when an accidental poisoning has occurred, such as when someone dies from eating deathcap mushrooms (Amanita phalloides. ... 

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