Of saponin

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). 

There has been considerable discussion regarding the mode of action of the sea cucumber and starfish saponins. Both the triterpene and steroidal glycosides inhibit both Na/K ATPase and Ca/Mg ATPase 06) possibly as a result of their aglycone structures. However, their detergent properties cause membrane disruption which will influence the activity of membrane-bound enzymes such as the ATPases. In investigating the actions of saponins on multilamellar liposomes, it was found that cholesterol serves as the binding site for such saponins and that cholesterol-free lip-somes are not lysed by saponins 107). 

ARAI I, KOMATSU Y, HIRAI Y, SHINGU K, IDA Y, YAMAURA H, YAMAMOTO T, KUROIWA Y, SASAKI K, TAGUCHI s (1997) Stimulative effects of saponin from kikyo-to, a Japanese herbal medicine, on pancreatic exocrine secretion of conscious rats. Planta Med. 63 419-24. 

Oleszek, W., Junkuszew, M., and Stochmal, A., Determination and toxicity of saponins from Amaranthus emeritus seeds, J. Agric. Food Chem., 47, 3685, 1999. Schliemaim, W. et al., Betalains of Celosia argentea. Phytochemistry, 58, 159, 2001. Stintzing, F.C., Schieber, A., and Carle, R., Amino acid composition and betaxanthin formation in fruits from Opuntia ficus-indica, Planta Med., 65, 632, 1999. 

Li da W, Lee EB, Kang SS, Hyun JE, Whang WK. Activity-guided isolation of saponins from Kalopanax pictus with anti-inflammatory activity. Chem Pharm Bull (Tokyo) 2002 50 900-903. 

Liming H U and Schlosser E (1976), Role of saponins in antifungal resistance. VI. Interactions Avena sativa-Drechslera avenacea , J Plant Dis Protect, 83, 317-327. 

Price K R, Johnson IT and Fenwick G R (1987), The chemistry and biological significance of saponins in food and feeding stuffs , Crit Rev Food Sci Nutr, 26, 27-133. 

Figure 3.8 Comparative saponin profiles for two cultivars of alfalfa and one cultivar of M. truncatula obtained by reverse-phase HPLC/PDA/MS using electrospray ionization and an ion trap mass spectrometer. The profiles illustrate the increased complexity of saponins in M. truncatula and offer a richer source for bio-prospecting of natural products.

HPLC/PDA/MS/MS characterization of saponins. We then applied this approach to... 

COSTELLO, C.E., Application of tandem mass spectral approach to structural determination of saponins. In Advances in Experimental Medicine and Biology (G. R. Waller and K. Yamaski, eds.), 405, Plenum Publishing, New York. 1996, pp. 317-329... 

HUHMAN, D.V., SUMNER, L.W., Metabolioc profiling of saponins in Medicago sativa and Medicago truncatula using HPLC coupled to an electrospray ion-trap mass spectometer, Phytochemistry, in press. 

A more detailed understanding of the biochemical pathways and enzymes involved in saponin biosynthesis will facilitate the development of plants with altered saponin content. In some cases, enhanced levels of saponins or the synthesis of novel saponins may be desirable (for example, for drug production 4 or improved disease resistance3,5,6), while for other plants, reduction in the content of undesirable saponins would be beneficial (for example, for legume saponins that are associated with antifeedant properties in animal feed7). This chapter is concerned with recent progress that has been made in the characterization of the enzymes and genes involved in the synthesis of these complex molecules and focuses on triterpenoid saponins. 

Cui, M., Song, F., Zhou, Y., Liu, Z., and Liu, S. (2000). Rapid identification of saponins in plant extracts by electrospray ionization multi-stage tandem mass spectrometry and liquid chromatography/tandem mass spectrometry. Rapid Commun. Mass Spectrom. 14, 1280-1286. 

Glensk, M., Czekalska, M., and Cisowski, W. (2001). Resolution of saponins from a ginseng preparation by 2D TLC with an adsorbant gradient. /. Planar Chromatogr. 14,454-456. 

Samukawa, K., Yamashita, H., Matsuda, H., and Kubo, M. (1995). Simultaneous analysis of saponins in ginseng radix by high performance liquid chromatography. Chem. Pharm. Bull 43, 137-141. 

Zhang, H., and Cheng, Y. (2006). Solid-phase extraction and liquid chromatography-electrospray mass spectrometric analysis of saponins in Chinese patent medicine of formulated Salvia miltiorrhizae and Panax notoginseng. J. Pharm. Biomed. Anal. 40,429 32. 

Wang J. (1982). [Quantitative determination of saponins in the roots of Panax notoginseng, P. ginseng, and P. quinquefolius.] Yaozue Tongbao. 17 244—45. 

Legumes Cardiovascular disease Presence of saponin which decreases cholesterol absorption from the gut... 

Unlike fungal saponinases, little is known about hydrolytic enzymes secreted by phytopathogenic oomycetes or their role in pathogenicity [75, 76]. Although innate resistance is believed to be the main mechanism by which oomycetes avoid the toxicity of saponins (see above), some oomycetes have been found to produce saponin hydrolases [77], as well as other glycosyl hydrolases [76]. 

Watanabe M et al (2005) Cloning and characterization of saponin hydrolases from Aspergillus oryzae and Eupenicillium brefeldianum. Biosci Biotechnol Biochem 69(11) 2178 Osbourn A (1996) Preformed antimicrobial compounds and plant defence against fungal attack. Plant Cell 8 1821... 

Kendall, W. A. and Leath, K. T. (1976). Effect of saponins on palatability of alfelfa to meadow voles. Agronomy Journal 68,473-476. 

Wang, D. M., K. Kubota and A. Kobayashi. Optical isomers of methyl jasmonate in tea aroma. Biosci Biotech Biochem 1996 60(3) 508-510. Kitagawa, I., S. Kobayashi, H. Sage-saka and T. Uemura. Extraction of saponins from tea leaves. Patent-Japan Kokai Tokkyo Koho-07 61,998 1995 9 pp. 

The distribution and structural elucidation of saponins have been reviewed. Glucuronides with a free carboxy-group and carbohydrate residues at C-2 and C-4 are readily cleaved with acetic anhydride in refluxing pyridine to give the genuine aglycone (see Vol. 7, p. 145). Details of the mass spectra of a series of permethylated oleanane saponins have been discussed. 

Fig. 1A-C. Examples of different classes of saponins A the triterpenoid saponin avenacin A-1 from roots of Avena spp B the steroidal saponin gracillin, from Costus speciosus C the steroidal glycoalkaloid a-tomatine from tomato (Lycopersicon spp.)...

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