Journal of Agricultural Research voi. xxii, no. i 



obtained in this manner was insufficient for a thorough investigation, 

 which must be deferred until a new lot of material is extracted. It was 

 nearest in color to the "lemon yellow" of Ridgway's ^ color standards 

 and melted to a cherrj^-red liquid at 220° to 222° C. A\Tien hydrolyzed it 

 produced quercetin and apparently only one sugar, glucose, although the 

 latter point is to be more thoroughly investigated. The osazone of the 

 sugar melted at 204° to 206° and was evidently glucosazone. The 

 quercetin obtained by hydrolysis was identified by its general properties 

 and by combustions both of the free flavonol and of the acetyl deriva- 

 tive. The latter melted at 191° to 193.5° and had the properties of 

 penta-acetylquercetin. A sample weighing 0.4650 gm. gave 0.2735 &^- 

 of quercetin, or 58.81 per cent by quantitative hydrolysis; theory requires 

 58.98 per cent. The results of combustions are given in Table III. 



Table III. — Combustions of the quercetin obtained by hydrolysis of the glucosid of brown 

 maize husks and of its acetyl derivative 



Penta- 

 acetyl- 

 quercetin. 



Weight of sample (gm.) 



Weight of carbon dioxid (gm.). 



Weight of water (gm.) 



Percentage of carbon 



Percentage of hydrogen 



0.1570 



.3400 



• 0537 

 59.06 



3-83 



Theory requires: For quercetin, carbon 59.59 per cent, hydrogen 3 .34 per cent; for penta-acetylquercetin, 

 carbon 58.59 per cent, hydrogen 3.90 per cent. 



The glucosid is not one of the well-known ones but bears considerable 

 similarity to one which Heyl ^ recently isolated from the pollen of rag- 

 weed, probably Ambrosia artemisiijolia L., although he gives only the 

 common name. 



SUMMARY 



In accord \vith the expectation that the broAvn-husked t5'pe of maize 

 would be found to contain a flavonol, we have been able to isolate from 

 brown husks both free quercetin and a quercetin glucosid of which a 

 further investigation will be made. 



The two compounds in question are both lemon yellow in color. If 

 they account for the truly brown color of the husks of this type, it must 

 be through their tinctorial quality, probably through their adsorption 

 on some colloid component of the brown tissues. 



It is very probable that the quercetin glucosid is the counterpart in 

 the brown type of the anthocyanin of the purple type. The pigment 

 of the latter will probably be found to be allied to cyanin. 



I RiDGWAY, Robert, color standards and color nomenclature. 43 p., 53 pi. (col.) Washington, 

 D. C. 1912. 



' Heyl, Frederick W. the yellow coloring substances of ragweed pollen. In Jour. Amer. 

 Chem. Soc, v. 41, no. 8, p. 1285-1289. 1919. 



