Quillaic acid

Quillaia Quillaja saponaria (Rosaceae) Quillaic acid... 

Quillaia bark or soapbark is derived from the tree Quillaja saponaria (Rosaceae) and other Quillaja species found in Chile, Peru, and Bolivia. The bark contains up to 10% saponins, a mixture known as commercial saponin , which is used for its detergent properties. Quillaia s surfactant properties are occasionally exploited in pharmaceutical preparations where it is used in the form of quillaia tincture as an emulsifying agent, particularly for fats, tars, and volatile oils. The bark contains a mixture of saponins which on hydrolysis liberates quillaic acid (Figure 5.62) as the aglycone, together with sugars, uronic acids, and acids from ester functions. 

The only vaccine adjuvants currently licensed by the FDA are aluminium salts. All other adjuvants are considered experimental and must undergo special preclinical testing. In the search for well-characterized adjuvants, the saponins from Quillaja saponaria, having quillaic acid as aglycone were shown to be potent immune adjuvants, such as Quil A (a purified mixture of 23 saponins), Iscoprep 7 0 3 which is a mixture of well characterized saponin fraction QH-A, QH-B, QH-C in a ratio 7 0 3 and the pure saponins QS-7, QS-17, QS-18, QS-21 (31) [41] (see Fig. (2)) and QS-L1 (32) [42]. 

The complex mixture of bisdesmosidic triterpene saponins, derived from gypsogenin (quillaic acid), of the extracts 1-3 reveals major dark-brown bands in the R, range 0.05-0.15 four to eight minor brown or violet zones are found in the R,- range 0.2-0.75 ( A), All zones are more easily characterized by their hemolytic reactions (—>B). 

China bark Murillo bark. Inner dried bark of Quillaja saponaria Molina, Rosaceae. Habit. South America (Peru, Chile) cultivated in Northern Hindustan. Constit Quillaic acid, quillajasaponin, sucrose, tannin. 

Pachorukow, Arbeiteti des Pharmakologischen Institute zu Dorpat I, 5 (1888) Cofman-Nicoresti, Pharm. J. Ill, 03 (1923), found the total saponin content of quillay bark to be about 9 or 10%. The saponin is built from quillaic acid, a sugar and possibly other Substances. 

In 1995, Liu et al. reported the isolation of three new saponins from the roots of G. oldhamiana [78], which has been used as a substitute for the well-known traditional Chinese medicinal herb Sterllaria dichotoma var. lanceo-lata in the treatment of fever, consumptive disease, and infantile malnutrition. The most polar saponin was a bisdesmoside and its structure was established as shown in Fig. (26). The other two saponins were monodesmosides derived from C-28 methyl esters of quillaic acid and gypsogenin and having identical sugar moieties at C-3. 

Two acylated saponins, tram- and cw-/ -methoxycinnamoyl triterpene glycosides, have recently been isolated from Silene jenisseensis (Caryophyllacea) [71]. Since these saponins contain quillaic acid as their aglycone (Fig. 11), they should be expected to have immunostimulating properties. However, no apparent immunostimulating activity was detected by an in vitro chemiluminescent granulocyte assay [4,71]. 

Segetalic acid, vaccaric acid, quillaic acid, gypsogenin, gypsogenic acid, 3,4-secogypsogenic acid... 

The adjuvant activity of saponins has been known for more than 50 years [10]. Commercially available saponins frequently consist of highly heterogeneous preparations of varying composition, sometimes being little more than crude extracts of the bark of the South American soap tree, Quillaja saponaria (Rosaceae), which may be contamined with tannins. The major components, however, are bidesmo-sidic quillaic acid triterpene-saponins [10]. 

The structure of QS-21 (3) is that of a quillaic acid substituted at position three by a branched trisaccharide and at position 28 by a linear tetrasaccharide and a dimeric fatty acyl group (3,5-dihydroxy-6-methyloctanoic acid) attached to the 4-position of the first sugar of the tetrasaccharide (fucose) by an ester linkage. A further sugar (arabinofuranose) is attached to the fatty acyl group. 

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