Sweet clover, Melilotus

E. S. P. Bromfield, L. R. Barran, and R. Weathcroft, Relative genetic structure of a population of Rhizobium meliloti isolated directly from soil and from nodules of alfalfa (Medicago. sativa) and sweet clover (Melilotus alba). Mol. Ecol. 4 183-188 (1995). 

Coumarin glycosides are found throughout the plant kingdom (Burrows and Tyrl, 2001). Seeds of Aesculus glabra (Ohio buckeye) contain the coumarin esculin, which is a mild neurotoxin. Sweet clovers Melilotus spp.) contain coumarins that are considered harmless unless moldy conditions exist, in which fungal activity produces the double coumarin dicoumarol. Dicoumarol is a... 

Coumarin was first isolated by Vogel in 1820 by extraction from tonka beans (Dipteryx odorata). It was subsequently identified in a large number of plants belonging to many different families. Its better known occurrences are in sweet clover (Melilotus alba and M. officinalis), sweet woodruff (Asperula odorata), vanilla leaf (Trilisa odoratissima), vanilla beans (Vanillaplanifolia), cassia (Cinnamorum cassia), lavender (Lavendula officinalis) and balsam of Peru (Myroxylon pereirae) (Perone, 1972 Maries et al, 1987 Boisde Meuly, 1993 Budavari, 1998). 

Sweet clover (Melilotus officinalis Desr) honey has a delicious flavor and is considered one of the best honeys. 

Indian tobacco Lobelia inflata Sweet clover Melilotus officinalis... 

Coumarin occurs in lavender, woodruff [Asperula), tonka beans, and sweet clover (Melilotus). Coumarin can be extracted from sweet clover with hot water. Reference (Sethna 1945)... 

The first anticoagulant rodenticide was dicoumarin (19). Its anticoagulant effect was first observed on cattle. Coumarin has an odour reminiscent of hay. When mown sweet clover (Melilotus albe) becomes mouldy, dicoumarin is formed from coumarin, and cattle fed with such mouldy, sweet clover hay bleed to deat when injured because of reduced blood coagulation (Campbell and Link, 1941 Stahmann et al., 1941). Dicoumarin, 3,3 -methylene-bis(4-hydroxycoumarin), is obtained by the condensation of 2 moles of 4-hydroxycoumarin (20) and 1 mole of formaldehyde in aqueous solution. 

Flowers of the three main forage plants in the study site were collected and analyzed for radionuchdes (gamma-emitting nuchdes and tritium). These flowers came from salt cedar (Tamarix ramosissima), white sweet clover Melilotus albus), and rabbit brush Chrysothamnus nauseosus). Results from this study indicated that there were no signiflcant differences in the amounts of radionuclides found in the flowers of these three plants. Figure 8.2 shows a series of boxplots of the floral sample concentrations. Detailed results from these experiments can be found in Flaarmann [23]. 

Red clover. Trifolium pratense, 580 Sweet clover, Melilotus spp., 519 Trefoil clovers, Lotus spp., 521 Trifolium spp., 180,580 White clover. Trifolium repens, 580 Coffee, Coffea arabacia, 2,65,489 Collards, Brassica spp., 249, 298, 772,796 Copper accumulator plant, 173 Becium homblei, 175 Aeolanthus spp., 175 Elsholtzia spp., 175... 

Although free coumarins are known to occur in plants, most simple coumarins occur as glucosides. The involvement of such glucosides in the biosynthetic sequence is a unique feature among higher plants. The -D-glucoside of o-coumarinic acid (7) (Fig. 9.2) is found in plants such as sweet clover (Melilotus alba) and lavender Lavandula officinalis). Usually, free coumarin (1) is formed by hydrolysis of the glucoside and subsequent lactonization of the Z-o-coumarinic acid (8). A similar situation probably is true for umbelliferone and scopoletin (Haslam, 1974). 

Dicoumarol is formed from melilotic acid (Fig. 299) by some microorganisms, e.g., Aspergillus fumigatus. The carbon of the methylene bridge may originate from a formaldehyde-equivalent. Dicoumarol is the toxic factor of decaying sweet clover (Melilotus officinalis). It inhibits blood coagulation. 

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