Water-pepper

Polygonum hydropiper L. La Lian (Water pepper) (whole plant) Persicarin, rhamnazin, isotadeonal, quercimeritrin, tadeonal.33 Improve indigestion, treat dysentery and enteritis. 

The hot-tasting sesquiterpene dialdehyde polygodial was first isolated from water pepper (Polygonum hydropiper, Fukuyama etal., 1982). 

Smartweed The water pepper (Persloarla hydropiper) aUo any of several speclea of persicarla having acrid juice. 

A variety of drimane-type sesquiterpenes occur in the plant Polygonum hydropiper which is also known as water pepper [88-90]. The main constituents of the leaves and seed are (-)-polygodial (22) and (-)-tadeonal drime-7-en-l 1,12-dial. These compounds were found to be cytotoxic and inhibit plant growth [91]. The synthesis of polygodial (22), an antifeedant and antimicrobial agent [92], can be formed in a few steps from (2E, 6E)-famesyl pyrophosphate, 53 [93]. The intermediate of the reaction is drimenol (54) (Scheme 1). 

Colourless liquid with a characteristic ammo-niacal smell m.p. 9 C, b.p. 106°C. Miscible with water. It is present in pepper as the alkaloid piperine from which it can be obtained by healing with alkali. It can also be prepared by the reduction of pyridine, either electrolytically or by other means. Piperidine is a strong base, behaving like the aliphatic amines. 

Elavored carbonated beverages, or soft drinks, were developed by apothecaries and chemists in the early nineteenth century by the addition of flavored symps to fountain-dispensed carbonated water. The introduction of proprietary flavors began in the late 1880s. Charles H. Hires introduced his root beer extract in 1876, Vemors s Ginger Ale was marketed by James Vernor in 1880, R. S. La2enby perfected the formula for Dr. Pepper in 1885, and John S. Pemberton developed the formula for Coca-Cola in 1886. Brad s Drink was introduced in 1896 and was later renamed Pepsi-Cola in 1898. 

Lachrymator A lachrymator is an irritant that causes tearing (watering of the eyes). Examples include onions, tear gas, and pepper spray (capsaicin). Some typical lachrymating chemicals are thionyl chloride (SOClj) and acrolein (CHj=CH-CHO). Certain chemicals may say lachrymator on the label so treat these with respect. Use these only in a fume hood. Goggles or safety glasses are not adequate protection for lachrymators, because the fumes can still reach your eyes directly or through inhalation. 

You can t remove the "hot" taste of chili peppers by drinking water because the compound responsible is nonpolar and water-insoluble. 

Dried or freeze dried samples can be extracted with water-immiscible solvents such as EtOAc or diethyl ether. For quantitative extraction, dried samples are preferably rehydrated at different times for example, 5 to 10 min for dried mangoes, 30 min for lyophihzed red peppers and pasta. Rehydration is followed by extraction with acetone or MeOH. Bixin and norbixin from a mix dry powder of annatto and com can quantitatively be extracted with MeOH followed by acetone. In order to improve pigment recovery, extruded foods require pre-digestion with enzymes to liberate the pigment from the matrix. ... 

Grapes, wine, raisins, tomatoes, potatoes, cereals (grain and straw), cucurbits (cucumbers and melons), lettuce, peppers, soil, water... 

Plants (rice, citrus, apple, pear, peach, apricot, grape, cotton, tea, tomato, cucumber, eggplant, pepper, squash), soil and water... 

Buprofezin and its metabolites, p-OH-buprofezin and BF12, are hydrophobic under neutral conditions. Having the organic base part in their chemical structure, these compounds form water-soluble salts under strongly acidic conditions. The change in solubilities of these compounds influences the cleanup procedure. Four different residue analytical methods have been developed to measure buprofezin and its metabolites in plants (rice, citrus and tomato cucumber, pepper, tomato, squash and eggplant), soil and water ... 

Why won t water relieve the burning sensation of chili peppers See p. 83. 

Question 7.2 Why Won t Water Relieve the Burning Sensation of Chili Peppers 83... 

Don t reach for that glass of water to cool the effect of spicy chili peppers A few rules of chemistry will suggest a better remedy. 

The effects on germination of microspores depend on the concentration and the distance from the object glass with microspores moistened with nutrient medium lavender oil (active matter) inhibit or not the process, while the volatile exretions from other plant species have no inhibitory, but stimulatory effects. Only water extract from red pepper demonstrates weak activity. 

In chemistry, the term complex can mean many things. The belief, which I shared, that complexes of the metal halides with monomers or with alkyl halides are important in CP induced me to undertake several difficult but fruitful investigations. Complexes between RX and MtXn were well known [see References in [24]] and they were being studied at about that time by several workers, such as H. C. Brown at Purdue University with regard to the A1 halides and Fairbrother at Manchester University was concerned with similar systems and with the ionisation of trityl halides by metal halides. I was concerned with TiCl4, my then favourite catalyst , and its interaction with the alkyl chlorides which were used as solvents for CP. The theory first suggested by Pepper [46] and adopted by us was that if a CP was initiated in an alkyl chloride RC1, and there was no evident effect of water, then the initiation was most likely akin to a Friedel-Crafts alkylation. This was represented by the equations (7) and (8) ... 

Relatively few attempts have been made to demonstrate the presence of ions in the polymerization of styrene, the most extensively studied of all monomers. Pepper [11] made conductivity studies on stannic chloride solutions in various solvents with and without monomer and added water, using open systems. He concluded that his results shed little light on the question of whether chain-carrying cations were present (which, indeed, he presumed) or on their concentration. Brown and Mathieson [12] found that for the polymerization of styrene by chloroacetic acids in nitromethane, the conductivity was indistinguishable from zero when no water was added, although the reaction rate was appreciable, and with increasing amounts of added water the conductivity increased, but the polymerization rate decreased. Therefore their results gave no useful information on the question of the participation of carbonium ions. 

A carbonium ion is formed by proton-transfer from the complex acid to the olefin. The polymerisation is initiated by the carbonium ion, and the growing end of the polymer consists of an ion-pair. For reactions in alkyl halide solvents the situation was less clear. Early experiments [8] suggested that the addition of water had little or no effect. This prompted Pepper [8] to suggest that the alkyl halide solvent itself was acting as co-catalyst ... 

The system styrene-sulphuric acid merits some special discussion. Gandini and Plesch [6, 7] were unable to reproduce the results of Pepper and his collaborators [8]. When a phial containing styrene was broken into a solution of sulphuric acid in methylene or ethylene dichloride at 20 °C only traces of polymer were obtained, apparently very rapidly, and thereafter no further polymerisation and no colour developed. These results are in essential agreement with those of Tsuda [9] who also found the polymerisation to be inhibited by water. 

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