Ants, stinging

Carboxylic acids with one acid group are known as monobasic acids while those with two acid groups are dibasic acids. All acids with more than one acid group are in the class of polybasic acids. The simplest organic acid, formic acid, is responsible for the irritation of bee and ant stings. Vinegar is a 5% solution of acetic acid in water. The acetic acid is responsible for the characteristic sour taste. Citric acid, found in citrus fruits and used in soft drinks, is a tribasic acid with three carboxylic acid groups. The dibasic acid, adipic acid, is a major component of nylon. 

Venoms causing anaphylaxis or other allergic reactions originate almost exclusively from social Hymenoptera, most often honeybees and vespids (fig. 1) [1], occasionally from bumble bees [2], in America [3] and in Australia [4], also from ants. Stings by other insects like mosquitoes, bedbugs, fleas, horse flies and midges can very rarely also cause systemic allergic reactions. These are however not due to venoms but to... 

Brown SG, Wu QX, Kelsall GR, et al Fatal anaphy- 11 laxis after jack jumper ant sting in southern Tasmania. Med J Aust 2001 175 644-647. 

Merck Co., Inc. Bee, wasp, hornet, and ant stings, Merck Web site. Available online. URL http //www.merck.com/mmhe/ sec24/ch298/ch298g.html. Accessed on March 19, 2008. 

Venoms from the fire ants Solenopsis invicta and 5. geminata are free of detectable histamine but possess histamine-release activity. This activity can account for the edema, itch, redness, warmth, and possibly the pain and burning sensations resulting from fire ant stings. And it can be attributed to the piperidines which constitute the major component of the venom. It has actually been proved that 6-methyl-2-n-undecylpiperidines (Ic and Id), components of S. geminata, possess the histamine-release activity (75). Due to some of the above-mentioned various activities the piperidine alkaloids play roles as defensive compounds. In addition to 2-alkyl-6-methylpiperidines, their N-methyl derivatives (3) are found in S. pergandei, S. carolinensis, and S. conjurata, and 1-piperideine derivatives (6 and 7) in S. sp. A (Puerto Rico) and S. xyloni (Table I). 

Methanoic acid is present in stinging nettles and ant stings. Ethanoic acid, however, is the most well known as it is the main constituent of vinegar. Like other acids, ethanoic acid affects indicators and will react with metals such as magnesium. However, whereas the mineral acids such as hydrochloric acid are called strong acids, ethanoic acid is a weak acid (Chapter 8, p. 120). Even though it is a weak acid, it will still react with bases to form salts. For example, the salt sodium ethanoate is formed when ethanoic acid reacts with dilute sodium hydroxide. 

The inhibition of the enzyme tyrosinase may very well be a key to the control of melanoma, and some of the known inhibitors include eommon substances. Thus, vitamin C, among other common and uncommon substances, has been listed as an enzyme inhibitor for tyrosinase in M.K. Jain s Handbook of Enzyme Inhibitors, 1965-1977 (1982). In addition to ascorbic acid (vitamin C), these other substances include the following halide ion (e.g., from the chloride of common salt, or from iodides and fluorides) butyric acid (from rancid butter) lactic acid (the end product of cancer cell metabolism, found naturally in sour milk products) oxalic acid (ordinarily considered toxic, although it occurs naturally in rhubarb and wood sorrel, etc.) formic acid (a component of ant stings) tyrosine itself and deadly cyanide (which is a chemically bound component of laetrile), as found in almonds (notably bitter almonds), in apricot seeds, and in certain legumes such as beans, etc., although the heat from cooking may drive off the cyanide content. 

The Sigma catalog lists tyrosinase, the enzyme involved in melanoma. As mentioned elsewhere, among the inhibitors listed in the handbooks of enzyme inhibitors are ascorbic acid, or vitamin C, halide ion (the halides being chlorides, notably, but also fluorides, bromides, and iodides), butyric acid (a component of rancid butter), lactic acid (the final product of anaerobic glycolysis, as occurs in cancer cell metabolism, and a component also of sour milk and buttermilk), oxalic acid (e.g., as found in rhubarb and in wood sorrel), formic acid (a component of ant stings), even tyrosine itself, and toxic cyanide ion. And, as has been indicated, alpine sunflower/yueea extract may possibly serve as an enzyme inhibitor for tyrosinase. 

Wasp stings are alkaline, and can be neutralised with vinegar. Why Ant stings and nettle stings contain methanoic add. How would you treat them ... 

Formic acid (also called methanoic acid) is the simplest carboxylic acid. Its chemical formula is HCOOH or HCO2H. It is an important intermediate in chemical synthesis and occurs naturally, most notably in the venom of bee and ant stings. In fact, its name comes from the Latin word for aat, formica, referring to its early isolation by the distillation of ant bodies. Esters, salts, and the anion derived from formic acid are referred to as formates. 

As we have seen, acids have different strengths depending on how much they dissociate in water. Because the dissociation of strong acids in water is essentially complete, the reaction is not considered to be an eqnilibrimn situation. However, because weak acids in water dissociate only slightly, the ion products reach equilibrium with the undissociated weak acid molecules. For example, formic acid HCHO2, the acid found in bee and ant stings, is a weak acid. Formic acid is an organic acid or a carboxylic acid in which the H written on the left of the formula dissociates to form formate ion. 

A red ant sting contains formic acid that irritates the skin. 

Many carboxylic acids are still named by their common names, which use prefixes form, acet, propion, butyr. These prefixes are related to the natural sources of the simple carboxylic acids. For example, formic acid is injected under the skin from bee or red ant stings and other insect bites. Acetic acid is the oxidation product of the ethanol in wines and apple cider. A solution of acetic acid and water is known as vinegar. Butyric acid gives the foul odor to rancid butter (see Table 14.1). 

What carboxylic acid is responsible for the pain of an ant sting ... 

Fox, R.W., and Lockey, R.F., 1982, Neurologic sequelae following the imported fire ant sting. J. Allergy Clin. Immunol. 70 120-124. 

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