Salicylic acid minerals

Manufacture. Several methods have been described for the preparation of -hydroxyben2oic acid. The commercial technique is similar to that of salicylic acid, ie, Kolbe-Schmitt carboxylation of phenol. The modification includes the use of potassium hydroxide in place of caustic (51). The dried potassium phenate is heated under pressure, 270 kPa (2.7 atm) or more, with dry carbon dioxide at 180—250°C. The potassium salt [16782-08-4] of Nhydroxyben2oic acid forms almost quantitatively and can be converted to free acid by using a mineral acid. 

Another limitation to the studies in Table 1 is the small number of plant species tested. Primarily monocotyledonous plants have been studied, although McClure et al. (26) found ferulic acid inhibitory in soybean. The restriction of studies to monocots is probably because the mechanism of mineral absorption has been more fully elucidated with monocots. Harper and Balke (32) reported some minor differences in the inhibition of K+ absorption by salicylic acid among oats (Avena sativa L.), wheat (Triticum aestlvum L.), barley, and maize roots. 

The short time periods (10 min to 4 hr) over which absorption was measured (Table 1) helps support the hypothesis that certain allelochemicals inhibit mineral absorption directly. Under acidic conditions (pH 4.0) salicylic acid inhibited K+ absorption within 1 min (32). The degree of inhibition remained constant over time when salicylic acid inhibited 1C " absorption (32) and when vanillic acid inhibited P0 absorption (28). Thus, at least phenolic acids appear to inhibit absorption rapidly and consistently. 

Two studies have used single cells to study the effect of phenolic acids on mineral absorption. In sterile cell cultures of Paul s Scarlet rose, 100 pM ferulic acid inhibited Rb+ absorption in about 10 min when the cells were 4-5 days old (37). Uptake from 0.2 mM RbCl was inhibited about 25% and absorption from 5.0 mM RbCl was inhibited 45%. Absorption by 10-day-old cells was affected little. Salicylic acid at 10 pM inhibited PO - absorption by Scenedesmus, a unicellular green alga (38). These studies show that allelochemicals inhibit mineral absorption in cellular systems as well as tissue systems (Table I). 

Benzoic acid derivatives also altered the electrical potential across the cell membrane in neurons of the marine mollusk Navanax lnermls (46). Salicylic acid (1-30 mM) caused a depolarization very rapidly (1-2 min) and decreased the ionic resistance across the membrane. As pH was decreased, more salicylic acid was required to reverse the effect of pH on the membrane potential (47). This result is contradictory to the influence of pH on the amount of salicylic acid required to affect mineral absorption in roots (32). The ability of a series of salicylic and benzoic acid derivatives to increase PD correlated with their octanol/water partition coefficients and pKa values (48). The authors proposed that the organic acid anions bound directly to membranes to produce the observed results. 

Effects of Allelochemlcals on ATPases. Several flavonoid compounds inhibit ATPase activity that is associated with mineral absorption. Phloretin and quercetin (100 pM) inhibited the plasma membrane ATPase Isolated from oat roots (33). The naphthoquinone juglone was inhibitory also. However, neither ferulic acid nor salicylic acid inhibited the ATPase. Additional research has shown that even at 10 mM salicylic acid inhibits ATPase activity only 10-15% (49). This lack of activity by salicylic acid was substantiated with the plasma membrane ATPase Isolated from Neurospora crassa (50) however, the flavonols fisetln, morin, myricetin, quercetin, and rutin were inhibitory to the Neurospora ATPase. Flavonoids inhibited the transport ATPases of several animal systems also (51-53). Thus, it appears that flavonoids but not phenolic acids might affect mineral transport by inhibiting ATPase enzymes. 

Effects of Allelochemlcals on ATP Supply. Allelochemlcals might decrease the ATP content of tissue by either increasing ATP utilization or decreasing ATP production. Some allelochemlcals that inhibit mineral absorption decrease ATP content of plant tissues. Salicylic acid decreased the ATP content of oat roots in a pH dependent manner (Figure 3). This result suggested that mitochondrial production of ATP was decreased in the tissue. On the other hand, Tillberg (38) found that salicylic acid and cinnamic acid increased the ATP content of Scenedesmus. Various flavonoids inhibited ATP production by mitochondria Isolated from cucumber (Cucumls satlvus L.) hypocotyls (54). Flavones such as kaempferol were more inhibitory than the corresponding flavanones. Substituted cinnamic acids such as caffeic acid were not inhibitory. 

Alteration of Membrane Permeability. The ability of allelochemicals to alter membrane permeability and thus inhibit mineral absorption has been investigated in detail with only phenolic acids. Salicylic acid induced the efflux of PO5 (28) and 1C" (42) from barley roots, but -hydroxybenzoic acid did not cause the efflux of K+... 

In addition to minerals, organic metabolites that absorb light at 260 nm leaked from oat roots in the presence of salicylic acid at pH 4.5 but not pH 6.5 (32). 

The effect of the surface area is far from being a simple one. It was shown for titania that when the surface area changes from 110 to 12 m2/g, the average time required for a complete mineralization of organic substrates increased from 40 to 75 and 50 to 75 min for salicylic acid and phenol, respectively [135], These results clearly show that textural properties, particularly the surface area, strongly affect the photoreactivity, although a high-temperature treatment improved their crystallinity [18], Therefore, this phenomenon may be explained only in connection with the catalyst surface dehydroxylation. 

In pond water, carbaryl degraded very rapidly to 1-naphthol. The latter degraded, presumably by Flavobacterium sp., into hydroxycinnamic acid, salicylic acid, and an unidentified compound (HSDB, 1989). Four d after carbaryl (30 mg/L and 300 ng/L) was added to Fall Creek water, >60% was mineralized to carbon dioxide. At pH 3, however, <10% was converted to carbon dioxide (Boethling and Alexander, 1979). Under these conditions, hydrolysis of carbaryl to 1-naphthol was rapid. The authors could not determine how much carbon dioxide was attributed to biodegradation of carbaryl and how much was due to the biodegradation of 1-naphthol (Boethling and Alexander, 1979). Hydrolysis half-lives of carbaryl in filtered and sterilized Hickory Hills (pH 6.7) and U.S. Department of Agriculture Number 1 pond water (pH 7.2) were 30 and 12 d, respectively (Wolfe et al., 1978). 

A pure culture of Arthrobacter sp. was capable of degrading isofenphos at different soil concentrations (10, 50, and 100 ppm) in less than 6 h. In previously treated soils, isofenphos could be mineralized to carbon dioxide by indigenous microorganisms (Racke and Coats, 1987). Hydrolyzes in soil to salicylic acid (Somasundaram et al., 1991). 

Traditionally, lead compounds have been discovered in one of two ways. The hrst is one of trial and error. This is the way many plant and animal products and minerals have been found to be effective in the treatment of some medical disorder. For example, no one knows when the hrst person learned that chewing on the bark of the willow tree [Salix alba) helped relieve pain and reduce fever, but willow bark has been used in many cultures for untold centuries for just that purpose. Today we know that the active ingredient in willow bark is a derivative of salicylic acid (CgH4(OH)COOH), which today is sold commercially as aspirin or one of its analogs. Drug researchers continue to rely heavily on the study of folk medicines—a science known as ethnopharmacology—for the discovery of new plant and animal products that may have medical applications in the modern world. Indeed, scientists have discovered that the medical... 

The reaction of salicylic acid with formaldehyde in the presence of catalytic amounts of strong mineral acid results in the condensation product... 

The esters of salicylic acid account for an increasing fraction of the salicylic acid produced, about 15% in the 1990s. Typically, the esters are commercially produced by esterification of salicylic acid with the appropriate alcohol using a strong mineral acid such as sulfuric as a catalyst. To complete the esterification, the excess alcohol and water are distilled away and recovered. The cmde product is further purified, generally by distillation. For the manufacture of higher esters of salicylic acid, transesterification of methyl salicylate with the appropriate alcohol is the usual route of choice. However, another reaction method uses sodium salicylate and the corresponding alkyl halide to form the desired ester. 

Salicylates give salicylic acid with mineral acids. When strongly heated gives C02 and phenol. Salicylic acid or salicylates mixed with soda-lime and heated give phenol, recognised by its smell. 

The physical and chemical characters of margarine, after melting and filtering, are naturally related to the fatty substances used in its preparation. For its analysis, use is made of the methods indicated for the various oils and fats (see Fatty Substances, Vol. I), and its distinction from butter is effected by the methods described for butter. Further, the methods there given are used for testing for various extraneous matters (flour, mineral substances), preservatives (salicylic acid, boric acid, etc.) and colouring matters. 

Miners JO, Grgurinovich N, Whitehead AG, Robson RA, Birkett DJ. Influence of gender and oral contraceptive steroids on the metabolism of salicylic acid and acetylsalicylic acid. Br J Clin Pharmacol 1986 22(2) 135-142. 

Iron(III) chloride solution intense violet-red colouration with neutral solutions of salicylates or with free salicylic acid the colour disappears upon the addition of dilute mineral acids, but not of a little acetic acid. The presence of a large excess of many organic acids (acetic, tartaric, and citric) prevents the development of the colour but the addition of a few drops of dilute ammonia solution will cause it to appear. 

Wet Tests.—The presence of iron in solution may readily be detected by a considerable number of sensitive reactions. Thus ferrous iron gives a green precipitate of ferrous hydroxide upon addition of excess of ammonium hydroxide. With potassium ferricyanide and a trace of acid, a deep blue precipitate—Turnbull s blue—is obtained. With potassium ferrocyanide a white precipitate is obtained in the entire absence of any ferric salt. Ferric iron, on the other hand, is usually characterised by its deep yellow or brown colour. Addition of concentrated hydrochloric acid deepens the colour. With excess of ammonium hydroxide, brown flocculent ferric hydroxide is precipitated. With potassium ferrocyanide solution, a deep blue colour is obtained in acid solution, whilst with potassium ferricyanide there is no action. Potassium thiocyanate gives in acid solution a deep red colour, which is not d troyed by heat. Salicylic acid gives a violet colour, provided no free mineral acid is present. 

A colorimetric method of estimating small quantities of uranium in solution depends upon the red colour obtained when a uranyl salt is treated with sodium salicylate. Free mineral acid, iron, acetic add, alcohol, or acetone must be absent, but neutral alkali salts do not interfere. 

Mineral oil—a mixture of liquid hydrocarbons obtained from petroleum. These are useful as levigating agents to wet and incorporate solid substances (e.g., salicylic acid, zinc oxide) into the preparation of ointments that consist of oleaginous bases as their vehicle. There are two types of mineral oils listed in the US. Pharmacopeia/National Formulary (USP/NF). Mineral oil USP is also called heavy mineral oil with a specific gravity between 0.845 and 0.905 and a viscosity of not less 34.5 cSt (cSt = mm /s) at 40°C. Light mineral oil, NF has a specific gravity between 0.818 and 0.880 and a viscosity of not more than 33.5 cSt. Table 2 lists the commercially available mineral oil fractions. 

The addition of dilute mineral acids to moderately concentrated solution of salicylates produces a white crystalline precipitate of the salicylic acid which when washed with cold water and dried, has the melting point of salicylic acid (1). 

Mineral surfaces can also activate molecules for photodecomposition by com-plexation reactions involving metal ions. For example, the reaction of substituted salicylic acid on Fe oxides ... 

---