Saponin

Saponins are widely distributed in plants and are a particular form of glycosides. They are so-called because of their soaplike effect, which is due to their surfactant properties. They also have hemolytic properties and, when injected into the bloodstream, are highly toxic. When taken by mouth, saponins are comparatively harmless. According to the structure of the aglycone or sapo-genin two kinds of saponin are recognized, the steroidal and triterpenoid type. 

Plant materials often contain triterpenoid saponin in considerable amounts. With regard to plants with antiulcer activity, licorice root contains about 2 to 12% of glycyrrhizic acid and the seeds of the horse chestnut up to 13% of aescin. Several plants containing high amounts have been shown to possess antiulcer activity in several experimental ulcer models (Table 64.2). 

Among these, saponins isolated from the rhizome of Panax japonicus and the fruit of Kochia scoparia (that contain approximately 20% of saponins) have been demonstrated to possess gastroprotective properties. Some oleanolic acid oligoglycosides, extracted from P. japonicus and K. scoparia, showed protective effects on ethanol- and indomethacin-induced gastric damage. Moreover, a methanol extract of P. japonicus rhizome was demonstrated to possess protective activity also on stress- or HCl-induced ulcers. The protective activities of all these active saponins are not due to inhibition of gastric acid secretion but probably due to activation of mucous membrane protective factors. 

Plants Containing Saponins with Antiulcer Activity 

Caffeine-arsenic, butadiene, pylorus ligated Stress, pylorus ligated, Escherichia coll Acetic acid, pylorus ligated Ethanol, indomethacin Psychological stress Stress, HC1 

Saponins are compounds that contain sugar chains and a triterpenoid aglycone (sapogenin) in their structure (Sparg et al., 2004). They are categorized according to the number of sugar chains in their structure as 

The sapogenin content in seeds of sweet genotypes varied from 0.02% to 0.04% and in seeds of bitter genotypes from 0.14% to 2.3% (Mastebroek et ah, 2000 Gitc 1 Li -Us tiindag and Mazza, 2007). These values are higher than those in soybean and oat, but lower than in green pea and yucca (G u c 1 Li -Us t Li n d a g and Mazza, 2007). 

Saponins have been considered toxic for different organisms. Meyer et ah (1990) found toxicity to brine shrimp. Woldemichael and Wink (2001) found monodesmoside saponins hemolytically active. The hemolysis may be produced by the interaction of the saponins with membranes, producing pores that lead to rupture of the (Seeman et ah, 1973). Kuljanabhagavad et ah (2008) described mainly saponins with an aldehyde group as cytotoxic in HeLa (cervix adenocarcinoma) cell line. 

Saponins are surface-active plant constituents, which are broken down into a carbohydrate portion and an aglycone on acid hydrolysis (Formula 16.5). The carbohydrate chain consists of 1 to 8 monosaccharides or uronic acids. It is usually branched and often terminated by a pentose, e. g., arabinose. There are saponins with one carbohydrate chain (mono-desmosides) and with two chains which are independent of each other (bisdesmosides). 

Saponins contribute to the characteristic taste of soybeans and other legumes. They are heat stable in the neutral pH range. Since a considerable portion of the saponins occurs in the seed coat and in the hypocotyl, the taste of soybean products, e. g., tofu, improves when these parts are removed. 

The saponins occur in the roots of many plants, notably the genus Saponaria, whose name derives from the Latin sapo, meaning soap, because of the latherlike reaction that occurs when parts of these plants are soaked in warm water. 

This ability to generate foams finds use in beverages such as ginger beer, shandy, cream soda and cola formulations to improve and standardise heading foam characteristics. 

Saponins for beverage use are sourced from quillaia bark (Quillaia saponaria Molina) and the yuccas. Of the latter species, two main varieties are used in the United States for production of the water extract the Mohave yucca (Yucca mohavensis) and the Joshua tree (Yucca brevifolia). At the levels used these additives are colourless and tasteless the dried extract, however, possesses an acrid, astringent taste. Permitted limits are quoted in terms of the dry weight of the extract. In the European Union, subject to Directive 95/2/EC, quillaia is permitted only in non-alcoholic drinks, to a maximum level of 200 mg/1. 

The saponins are an important class of glycosides widely distributed in plants. Saponin solutions foam easily. Given intravenously they are poison- 

Strain, in Organic Chemistry (H. Gilman, ed.), 2nd ed., p. 1454. Wiley, New York, 1943 L. Kofler, Die Saponine Springer, Vienna, 1927 R. Tschesche, Fortschr. Chem. org. Naturstoffe 1, 1 (1945) L. F. Fieser and M. Fieser, Natural Products Related to Phenanthrene, 3rd ed. Reinhold, New York, 1949. 

Two classes are recognized, the so-called neutral saponins (digitalis saponins), which have as aglycons substances derived from cyclopentano-perhydrophenanthrene, and the acid saponins, which have as aglycons substances derived from triterpene. The aglycons are called sapogenins. Most of the investigations have been devoted to the determination of the structures of the neutral saponins. 

The formulas of a typical neutral saponin, sarsasaponin from Radix sarsaparillae 25), and the acid saponin of sugar beets Beta vulgaris), the glucuronide of oleanolic acid 26), are given. 

Saponin, derived from the bark of the quillaja (Quillaja saponarid) tree, is also used as an adjuvant. Saponins are nontoxic when administered orally. 

Biopharmaceuticals in Plants Toward the Next Century of Medicine 

These are not true triterpenes since their C27 ring skeletons cannot be broken down into isoprene units, although they have a common biosynthetic origin to triterpenes via the mevalonic acid pathway. They are sometimes referred to as nortriterpenes. Some including 

A subgroup of the steroidal saponins are the glycoalkaloids, in which the aglycone is a steroidal alkaloid (contains a nitrogen atom). The most common source of these compounds is the Solanum genus, including the common potato Solanum tuberosum. 

Saponins can also be classified according to the way the aglycones are bonded to their sugar moieties  

The pharmacological activities of saponins were recently reviewed by Lacaille-Dubois and Wagner (1996). Apart from the local detergent and wound-healing effects, saponins have a range of systemic effects according to their chemical structures (see Table 6.1). 

Due to their detergent effects noted earlier, saponins are capable of increasing permeabiUty of membranes. They can cause haemolysis by destroying the membranes of red blood cells, thus releasing the haemoglobin—a major concern when saponins are injected as this may lead to anaemia and renal failure due to the sudden influx of haemoglobin into the bloodstream. 

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Saponins dismpt red blood cells and may produce diarrhea and vomiting. They may also have a beneficial effect by complexing with cholesterol [57-88-5] and thus lowering semm cholesterol levels (24,25). In humans, intestinal microflora seem to either destroy saponins or inactivate them in small concentrations. 

Alginates, alkaloids, glycerides, gutta, phenols, rosins, rubber, saponins sterols, tall oils, tannins, terpenes, waxes... 

Soybeans and peanuts also contain saponins, which are glucoside derivatives of triterpenoid alcohols (37). Saponins range from 0.09 to 0.32% in 457 soybean varieties (38). 

Sapogenins and Saponins. Steroids isolated from a variety of plant sources that contain a spiroketal between hydroxyl moieties at C16 and C26 and a carbonyl at C22 are called sapogenins (33). 

Saponins. Although the hypocholesterolemic activity of saponins has been known since the 1950s, thek low potency and difficult purification sparked Htde interest in natural saponins as hypolipidemic agents. Synthetic steroids (292, 293) that are structurally related to saponins have been shown to lower plasma cholesterol in a variety of different species (252). Steroid (292) is designated CP-88,818 [99759-19-0]. The hypocholesterolemic agent CP-148,623 [150332-35-7] (293) is not absorbed into the systemic ckculation and does not inhibit enzymes involved in cholesterol synthesis, release, or uptake. Rather, (293) specifically inhibits cholesterol absorption into the intestinal mucosa (253). As of late 1996, CP-148,623 is in clinical trials as an agent that lowers blood concentrations of cholesterol (254). 

Glycosides, particularly of phenoHc compounds, are widely distributed in plant tissues (2,10). Glycosides of anthocyanidins, flavones, flavanols, flavanones, flavanonols, stilbenes and saponins, gaUic acid derivatives, and condensed tannins are all common. 

Berkman and Egloff explain that some additives increase the flexi-bihty or toughness of bubble walls, rather than their viscosity, to render them more durable. They cite as illustrations the addition of small quantities of soap to saponin solutions or of glycerin to soap solution to yield much more stable foam. The increased stability with ionic additives is probably due to elec trostatic repulsion between charged, nearly parallel surfaces of the hquid film, which acts to retard draining and hence rupture. 

The effective surface viscosity is best found by experiment with the system in question, followed by back calculation through Eq. (22-55). From the precursors to Eq. (22-55), such experiments have yielded values of [L, on the order of (dyn-s)/cm for common surfactants in water at room temperature, which agrees with independent measurements [Lemhch, Chem. Eng. ScL, 23, 932 (1968) and Shih and Lem-lich. Am. Inst. Chem. Eng. J., 13, 751 (1967)]. However, the expected high [L, for aqueous solutions of such sldn-forming substances as saponin and albumin was not attained, perhaps because of their non-newtonian surface behavior [Shih and Lemhch, Ind. Eng. Chem. Fun-dam., 10, 254 (1971) andjashnani and Lemlich, y. Colloid Inteiface ScL, 46, 13(1974)]. 

Alkaloid- and saponin-containing drugs, as well as bearberry leaves, as a moderately fine powder (particle size ca. 0.5 mm). 

These methods are employed for the detection and determination of antibiotics and substances with similar effects, like alkaloids, insecticides, fungicides, mycotoxins, vitamins, bitter principles and saponins [14]. 

A skinned fiber is a muscle fiber, the sarcolemma of which has been mechanically removed or which is made freely permeable to small molecules, such as Ca2+, Mg2+, EGTA, ATP, soluble enzymes and others by a chemical agent (saponin, (3-escin or Staphylococcus a-toxin). The organization of the sarcoplasmic reticulum (SR) and myofibrils is kqrt as they are in the living muscle. 

The first soaps were probably the saps of plants such as Chloro-galum pomeridianum, the roots of which can be crushed in water to form a lather. Other plants, such as soapbark (Quillaja saponaria), soapberry (Sapindus mukorossi), and soapwort (Saponaria officinalis) also contain the same main ingredient, a compound called saponin, which forms the foamy lather. 

Saponin can also be used in fishing a toxin, it is introduced into streams to stupefy fish and make them easy to catch.)... 

Saponins la 7,411,430 -, bioautographic determination la 109 Sarcosine Ia435 lbl24 Scandium cations, detection la 144 Scanner, optical trains la 30,39 S-Chamber (small chamber) la 126,127 SCHiFF s bases lb 52 Scintillators la 12 Scopolamine lb 231,252,255,323 Scopoletin lb 216-218,365 Screening process lb 45 Sebacic acid la 178,233,249,308 Sebuthylazine lb 418 Selectivity, enhancement by derivatiza-tion la 55... 

Sandwich chamber 126,127 Sapogenins 43,195, 206, 411 -, steroid 69, 206 -, trifluoroacetates 69 Saponins 7,109, 411, 430 Sarcosine 435 Scandium cations 144 Scanners, optical trains 30, 39 S-chamber see Sandwich chamber Scintillators 12 Sebacic acid 178,233,249, 308 Selectivity... 

E. C. (1988b). Incorporation of the major outer membrane protein of Neisseria gonorrhoeae in saponin-Upid complexes (Iscoms) Chemical analysis, some structural features, and comparison of their immunogenicity with three other antigen delivery systems, Inf. Immun., 56, 432-438. 

MTX exceeds any other marine toxins known in the mouse lethality (0.13 ig/kg) and is 80 times more potent than commercial saponin (Merck) in hemolytic activity. According to Terao (72), MTX induced severe pathomorphological change in the stomach, heart and lymphoid tissues in mice and rats by i.p. injection of 200... 

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