RECENT WORK IN AGRICULTURAL SCIENCE. 



CHEMISTRY. 



Legumin and other proteids of the pea, lentil, horse bean, and 

 vetch, T. B. Osborne and G. F. Campbell (Connecticut State Sta. 

 Ept. 1897, pp. 324-373). — The authors give in detail the methods and 

 results of extensive investigations on the proteids of these seeds. They 

 find that they all contain legumin, legumelin, and proteose, and that 

 in addition the seeds of the pea, lentil, and horse bean contain vicilin. 

 No difference was found in the reactions and properties of preparations 

 of each of these proteids from the different seeds. 



The results of the investigation are summarized as follows: 



"Legumin. — Leguuiin forms the chief proteid constituent obtainable from the 

 vetch, pea, lentil, and horse bean. In the first-named seed about 10 per cent of the 

 meal was found to consist of legumin; in the three other seeds this proteid is asso- 

 ciated with vicilin, from which we have no method for its quantitative separation. 

 From the pea about 10 per cent, from the lentil 13 per cent, and from the horse bean 

 about 17 per cent of these mixed proteids were obtained. The lentil contains the 

 least proportion of legumin, which seems to form about two-thirds of the mixed 

 proteids, while the horse bean contains the greatest, as in this seed vicilin is present 

 in relatively small amount. 



"Legumin is a globulin, for it dissolves readily in saline solutions and is precipi- 

 tated therefrom either by dialysis, dilution, or cooling. By dialysis or by cooling it 

 separates in the form of spheroids, which, after settling from the solution, unite to 

 form a plastic mass. By diluting its concentrated solutions the legumin separates 

 as a viscid translucent fluid. This fluid when treated with water becomes opaque 

 and solid, so that the legumin can be converted into a coarse meal by rubbing with 

 a glass rod under water. Conglutin from lupine seeds and amandin from almonds 

 behave similarly, as do gliadin of wheat and rye and hordein of barley when precip- 

 itated from alcoholic solutions by dilution with water. 



"Solutions containing more than 2 per cent of sodium chlorid dissolve legumin 

 abundantly, those containing less salt have a solvent power rapidly decreasing with 

 the diminishing salt content, so that a 1 per cent salt solution dissolves very little. 

 Saturation with sodium chlorid or magnesium sulphate does not precipitate legumin 

 from its solution in brine, but saturation with sodium sulphate at 34° precipitates it 

 almost completely. 



"In pure water legumin is entirely insoluble, but if the solution from which the 

 legumin is precipitated contains acid, this may combine with the legumin and the 

 resulting preparation, like other acid globulins, will then dissolve in pure water. 



"If seeds containing legumin are extracted with water, more or less of the legu- 

 min is dissolved; from the pea about 4 per cent, from the vetch 2.5 per cent, from 

 the lentil 10 per cent, and from the horse bean 16 per cent. The legumin thus dis- 

 solved is largely precipitated by dialysis in water, by the addition of acids and 

 by lime salts, and very slightly by great dilution with water. These aqueous 

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