Query: Saponins

title: The biological action of saponins in animal systems: a review.
abstract: Saponins are steroid or triterpenoid glycosides, common in a large number of plants and plant products that are important in human and animal nutrition. Several biological effects have been ascribed to saponins. Extensive research has been carried out into the membrane permeabilising, immunostimulant, hypocholesterolaemic and anticarcinogenic properties of saponins and they have also been found to significantly affect growth, feed intake and reproduction in animals. These structurally diverse compounds have also been observed to kill protozoans and molluscs, to be antioxidants, to impair the digestion of protein and the uptake of vitamins and minerals in the gut, to cause hypoglycaemia, and to act as antifungal and antiviral agents. These compounds can thus affect animals in a host of different ways both positive and negative.

title: Biological activities and distribution of plant saponins.
abstract: Plant saponins are widely distributed amongst plants and have a wide range of biological properties. The more recent investigations and findings into their biological activities were summarized. Isolation studies of saponins were examined to determine which are the more commonly studied plant families and in which families saponins have been identified.

title: Saponins as Insecticides: a Review
abstract: Chaieb, I. 2010. Saponins as insecticides: a review Tunisian Journal of Plant Protection 5: 3950. Saponins are heterosides (substances containing in their structure one or more sugar molecule) of plan t origin. This type of molecules has an interesting p esticide potential and this review constitutes an inventory of principal researches realized in this direction. In the first part of this review, saponi ns are defined and their different structural families are presented. The biological significance and princip al sources of saponins were also outlined. The second part of this review focused on insecticidal activit ies of saponins. In fact, these substances are known by their toxicity to harmful insects (anti feeding, disturbance of the moult, growth regulation, mortal ity. the insecticidal activity of saponins is d ue to their interaction with cholesterol, causing a distu rbance of the synthesis of ecdysteroids. These substances are also protease inhibitors or cytotoxi c to certain insects. The third part of the review gave an idea on the limits which can slow down the use o f saponins as insecticides: saponins have a strong toxicity to mammals because of their cytotoxic and haemolytic activities. The second constraint is the loss of molecule activity due to degradation of sug ars associated with the aglycone. The hydrophilic nature of saponins limits their penetration through the lipophilic insect cuticle. The structural complexity of saponins limits the exact identificat ion and synthesis of active molecules.

title: Triterpenoid saponins.
abstract: Triterpenoid saponins are naturally occurring surface active glycosides of triterpenes. They can be divided into two major groups a) monodesmosides in which the aglycone has a singly attached linear or branched chain set of sugars and (b) bisdesmosides in which there are two sets of sugars. They are widely distributed in plant kingdom, certain marine organisms and marine flora and fauna. Their structural diversity, occurrence as complex mixtures, novel bioactivities of relevance to the pharmaceutical industry and agriculture, and usefulness as ingredients of cosmetics, allelochemicals, food and feeding stuff has generated great interest in the study of these molecules. With the introduction of advanced methods of isolation and structure determination there has been increased activity in these molecules. In recent years, the discovery of novel triterpenoid saponins with important biological activity, enhanced stability and toxicity has also led to the exploration the structure activity relationships. The great structural diversity of saponins due to their various biosynthetic origins, the challenges of identification, the novel biological activities, possibility of developing potent herbal drugs for human society, novel biosynthetic processes and semi and total synthesis of saponins are now opening up new opportunities or newer trends for exploitation of novel saponins. Several reviews on triterponoied saponins have been published in recent years [1 5] This review is concerned with the latest developments in isolation and structure elucidation of triterpenoied saponins and contains a compilation of the 13C NMR data of the novel aglycones of triterpenoid saponins, published during mid 1996 March, 2007 and arranged skeleton wise, together with the biological activities reported.

title: Saponins as cytotoxic agents: a review
abstract: Saponins are natural glycosides which possess a wide range of pharmacological properties including cytotoxic activity. In this review, the recent studies (2005 2009) concerning the cytotoxic activity of saponins have been summarized. The correlations between the structure and the cytotoxicity of both steroid and triterpenoid saponins have been described as well as the most common mechanisms of action.

title: Saponins: Properties, Applications and Processing
abstract: Saponins are a diverse group of compounds widely distributed in the plant kingdom, which are characterized by their structure containing a triterpene or steroid aglycone and one or more sugar chains. Consumer demand for natural products coupled with their physicochemical (surfactant) properties and mounting evidence on their biological activity (such as anticancer and anticholesterol activity) has led to the emergence of saponins as commercially significant compounds with expanding applications in food, cosmetics, and pharmaceutical sectors. The realization of their full commercial potential requires development of new processes/processing strategies to address the processing challenges posed by their complex nature. This review provides an update on the sources, properties, and applications of saponins with special focus on their extraction and purification. Also reviewed is the recent literature on the effect of processing on saponin structure/properties and the extraction and purification of sapogenins.

title: Antifungal Activity of C 27 Steroidal Saponins
abstract: As part of our search for new antifungal agents from natural resources, 22 C 27 steroidal saponins and 6 steroidal sapogenins isolated from several monocotyledonous plants were tested for their antifungal activity against the opportunistic pathogens Candida albicans, Candida glabrata, Candida krusei, Cryptococcus neoformans, and Aspergillus fumigatus. The results showed that the antifungal activity of the steroidal saponins was associated with their aglycone moieties and the number and structure of monosaccharide units in their sugar chains. Within the 10 active saponins, four tigogenin saponins (compounds 1 to 4) with a sugar moiety of four or five monosaccharide units exhibited significant activity against C. neoformans and A. fumigatus, comparable to the positive control amphotericin B. The antifungal potency of these compounds was not associated with cytotoxicity to mammalian cells. This suggests that the C 27 steroidal saponins may be considered potential antifungal leads for further preclinical study.

title: Biosynthesis of triterpenoid saponins in plants.
abstract: Many different plant species synthesise triterpenoid saponins as part of their normal programme of growth and development. Examples include plants that are exploited as sources of drugs, such as liquorice and ginseng, and also crop plants such as legumes and oats. Interest in these molecules stems from their medicinal properties, antimicrobial activity, and their likely role as determinants of plant disease resistance. Triterpenoid saponins are synthesised via the isoprenoid pathway by cyclization of 2,3 oxidosqualene to give primarily oleanane (beta amyrin) or dammarane triterpenoid skeletons. The triterpenoid backbone then undergoes various modifications (oxidation, substitution and glycosylation) mediated by cytochrome P450 dependent monooxygenases, glycosyltransferases and other enzymes. In general very little is known about the enzymes and biochemical pathways involved in saponin biosynthesis. The genetic machinery required for the elaboration of this important family of plant secondary metabolites is as yet largely uncharacterised, despite the considerable commercial interest in this important group of natural products. This is likely to be due in part to the complexity of the molecules and the lack of pathway intermediates for biochemical studies. Considerable advances have recently been made, however, in the area of 2,3 oxidosqualene cyclisation, and a number of genes encoding the enzymes that give rise to the diverse array of plant triterpenoid skeletons have been cloned. Progress has also been made in the characterisation of saponin glucosyltransferases. This review outlines these developments, with particular emphasis on triterpenoid saponins.

title: Saponins in Tribulus terrestris Chemistry and Bioactivity
abstract: Tribulus terrestris is a valuable herb known for its application in the folk medicine in many parts of the world. Furostanol and spirostanol saponins of tigogenin, neotigogenin, gitogenin, neogitogenin, hecogenin, neohecogenin, diosgenin, chlorogenin, ruscogenin and sarsasapogenin type are frequently found in this plant. Four sulphated saponins of tigogenin and diosgenin type are also isolated. Extracts and steroidal saponins have been found to possess various pharmacological activities. Preparations based on the saponin fraction of T. terrestris are used for treatment of infertility and libido disorders in men and women, as well as for treatment of cardiac diseases. Food supplements containing T. terrestris extracts are on sale in USA and Europe with claim of a general stimulating action.

title: Alfalfa Saponins and Their Implication in Animal Nutrition.
abstract: Alfalfa (Medicago sativa L. is of immense importance as livestock fodder for both developed and lesser developed countries as it contains a high amount of protein, and yield of dry matter is also very high. The main antinutritional components present in this plant are saponins, and their unfavorable effects on animal performance have restricted the optimum use of this high protein plant as an animal feed. The occurrence, chemistry, analysis, and consequences of intake of alfalfa saponins are reviewed. The information synthesized may lead to planning of more detailed studies on isolation and characterization of saponins and sapogenins to gain a better understanding of the biological activities of the aglycon and carbohydrate moieties of saponins.