AGBICULTURAL CHEMISTRY — AGKOTECHNY. 311 



pp. 327, 328).— The compound previously noted (E. S. R.. 26, p. 208), which 

 melts at over 200" C, can be separated by treatment of the apple skins with 

 ether into an insoluble substance " of high melting point, and a waxy substance 

 crystallizing in needles, melting point GS.5°. On distillation under diminished 

 pressure, the oil obtained by extracting the skins with'ether yields a crystalline 

 substance of low melting point having an odor of apples and a yellow oil which 

 readily solidifies. The behavior of the skins on distillation is also described." 



The study of the ripening of fruit, A. Contino (Staz. Sper. Agr. Hal., Jf5 

 (1912), No. 5-6, pp. 460-472; abs. in Chem. Ahs., 7 {1913), No. 19, p. 3373).— 

 " Kaki plums wore u.sed. One sample was analyzed immediately; the second 

 sample was kept in air 1 month; the third sample was preserved in paraffin. 

 Results showed that the second sample had lost in weight through respiration. 

 The constituents, however, remained the same as in the sample preserved with 

 paraffin, except in the case of pectins, of which the third sample contained three 

 times as much as the second sample. The formation of pectins, therefore, has 

 nothing to do with the atmosi)heric oxygen but is brought about by the intemial 

 decomposition of the tannin. The fruit contained no sucrose." 



The constituents of hops, F. B. Power. F. Ttjtin, and H. Rogerson (Jour. 

 Chem. Soc. [London], 103 (1913), No. 609, pp. 1267-1292).— The material used 

 in this investigation consisted of good Kentish hops, harvested in 1011. The 

 air-dried hops contained 30.48 per cent of moisture. 2.4 per cent of tannin, and 

 7.919 per cent of ash. 



The work emphasizes the fact that the bitterness of hops is not due to a 

 single substance but to a number of products, some of these soluble in alcohol 

 and others soluble in water. One of these, which was a well-definetl. crystal- 

 line, bitter substance, termed humulol. CnHisOi, was isolated from the resin. 

 It is phenolic in character, melts at V.)0° C.. is fawn-colored, and on hydrolysis 

 with potassium hydroxid yields among other products an acid. CisHi.Or.. melting 

 point 210°. and p-hydroxybeuz:ildeIiyde. Another crystalline compound, desig- 

 nated as xanthohumol, CisIIhOj (melting point 172°), which is tasteless and 

 possesses an orange-yellow color, was also isolate<l. 



That hops contain a yellow coloring matter resembling quercitrin and myri- 

 cylpalmitate could not be confirmed. It is shown that the alcoholic extract, 

 which consisted of a dark green, oily resin (equivalent to 34.1 per cent of the 

 weight of the hops), contained " ceryl alcohol, CirHsr.O. hentriacontane, CsiHm; 

 a phytosterol. C27H46O; a phytosterolin (phytosterol glucosid), CasHsoOa; a mix- 

 ture of volatile fatty acids, consisting of formic, acetic, butyric, and valeric 

 acids, together with a hexenoic acid, CeHioO- (boiling ix)int 204 to 208°), 

 which was identified as B-isopropylacrylic acid, and apparently a little nonoic 

 acid, C»HisOj, was also present; saturated and unsaturated nonvolatile acids, 

 comprising palmitic, stearic, and cerotic acids, and an acid, C20H40O2 (melting 

 point 62.5 to 63°), which is apparently an isomerid of arachidic acid; further- 

 more, cluytinic acid, CnH^Oj (melting point 69°), the methyl ester of which 

 melts at 47°, and linolic acid." 



*' From the portion of the extract which was soluble in water there were iso- 

 lated small amounts of cholin. C5H15O1.N, and 1-asparagin, C4HSO3N2. both of 

 which had pi'eviously been observed to be present, although no evidence of the 

 identity of the last-mentioned substance api^ears to haVe hitherto been recorded. 

 The aqueous liquid also contained, besides tannin, a quantity of potassium 

 nitrate and a sugar which yielded d-phenylglucosazone (melting point 208°), 

 together with dark-colored, amorphous material which possessed an intensely 

 bitter taste. A volatile base, having a conin-like odor, was also obtained, but 

 the amount was so extremely small that it could not be further characterized." 



