Medicagenic acid

Figure 3.10 HPLC/MS/MS tandem mass spectrum of 3-Glc-28-Glc medicagenic acid obtained using an ion-trap mass analyzer. The spectrum illustrates the successive loss of two hexoses, the deprotonated aglycone, and a characteristic ftagment ion associated with medicagenic acid saponins.

A remarkable number of insecticidal plants seem to have been recognized first as fish poisons. This group has received special scientific attention for example, the already mentioned rotenone and other rotenoids of Perris and Lonchocarpus species (3-6), the lupine alkaloids of Sophora species (13), and a saponin (medicagenic acid) from Medlcago sativa leaves ( ). 

Levy, M., Zehavi, U., Naim, M., Itzhack, P. An improved procedure for the isolation of medicagenic acid 3-0-B-D-glucopyranoside from alfalfa roots and its antifungal activity on plant pathogens. J Agric Food Chem... 

The profile of the incorporation of from acetate into medicagenic acid (102) in Medicago media suggested that it is the first saponin synthesized in the germinating seeds. 

O-glucoside of medicagenic acid (78) Alfalfa Cryptococcus neoformans MFC 4 [129]... 

G. HMBC experiment performed on the derivatized saponin (256 experiments of 2K, reverse mode without decoupling in the carbon dimension experiment is not phased). Part of the map corresponding to the high field resonances (methyls) is shown below. The observed correlations allow assignment of most of the carbons of the triterpene (medicagenic acid). Carbon assigned by means of HMQC appear as squares on the formula and carbon assigned by means of HMBC appear as circles. 

Although there are also substantial amounts of the soya -saponins present in alfalfa, these do not apparently contribute to chick growth or egg production inhibition and are not precipi-table with cholesterol. (Reshef, et al., 1976) The ability to complex with cholesterol also apparently accounts for the fungistatic activity of the saponins of both medicagenic acid and hederagenin. 

The saponin contents of a number of vegetable food products are presented in table 5. Most of the food products contained levels of saponin similar to that in the white LPC. However, the commercial sample of alfalfa sprouts contained a level of saponin far exceeding any of the food products or any of high saponin alfalfa meal samples analyzed at the laboratory. This apparant high saponin content of the alfalfa sprouts may be due in part to the shortened carbohydrate side chain attached to the medicagenic acid aglycone. The alfalfa sprouts bearing a resemblance to alfalfa roots in this respect. Further studies will be needed to confirm this possibility. 

Tabopda TK, Mitaine-Offer AC, Miyamoto T, Tanaka C, Ngadjui BT, Miijolet JF, Duchamp O, Lacaille-Dubois MA (2011) Three new medicagenic acid saponins from Poly gala micrantha Guill Perr. Helv Chim Acta 94 914—922... 

Celosins (A-G), oleanolic acid, celosin (H-J), 3-0-P-D-xylopyranosyl-(l - 3)-P-D-glucuronopyranosyl-polygalagenin 28-0-P-D-glucopyranosyl ester, 3-0-P-D-glucuronopyranosyl-medicagenic acid... 

P-D-xylcopyranosyl-(l 4)-a-L-rhamnopyranosyl-(l 2)-P-D-fucopyranosyl ester, and 3-O-P-D-glucuronopyranosyl-medicagenic acid 28-O-a-L-arabinopyranosyl-(l 3)-[P-D-xylopyranosyl-(l 4)]-a-L-rhamnopyranosyl-(l 2)-P-D-fucopyranosyl ester... 

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