76 STUDIES ON APPLES. 
trated at the lowest possible temperature. Alcohol was added and 
resulting gelatinous precipitate after filtering off was dissolved in 
water. After digesting for one hour with 1 per cent hydrochloric acid 
at 60° C., and filtering, two precipitates were formed on fractional 
precipitation of the filtrate with alcohol. The first, after repeated 
solution and precipitation with water and alcohol respectively, was a 
white weakly acid mass, precipitated by barium chlorid and lead ace- 
tate, of strongly dextro-rotatory power ([@]p=-+ 167.4°), and yielding 
20 per cent of mucic acid on oxidation. The second, after purifica- 
tion in the same way, was an amorphous white substance, precipitated 
by lead acetate, but not by barium chlorid, showing less dextro- 
rotation ([@]p»>=+ 123.8°), and gave no muciec acid on oxidation, but 
yielded with phloroglucin and hydrochloric acid an intense color 
reaction denoting pentoses or pentosans. 
Tromp de Haas and Tollens“” gave the ultimate composition and 
products of hydrolysis by sulphuric acid of pectins from many 
sources. Their results showed that the relation of hydrogen and 
oxygen in these bodies was nearly 1 to 8, as required by the carbohy- 
drate formula, and that the pectin bodies which they-studied contained 
no complex which gave rise to dextrose, but that complexes were pres- 
ent which yielded pentose sugars and galactose on hydrolyzing with 
acids. 
Tollens’ in a later paper says that pectin bodies may probably be 
regarded as glucosides, since the acid reaction, combination with bases, 
and slightly higher oxygen-hydrogen ratio of extracted pectins indi- 
cate the presence of carboxyl groups. The pectin in the plant may 
not have acid properties, but may exist as a lactone. 
Andrlik® discusses the action of dilute hydrochloric acid in the cold 
on beet mare. A pectin of specific rotatory power ([@]p=+214.4° to 
220) was extracted, and purified by repeated precipitation with alco- 
hol. The longer the acid acted on the beet marc, the more insoluble 
in water was the pectin dissolved. 
Bourquellot and Hérissey,/ and later Bourquellot’ alone, studied the 
extraction of pectins with hot water, and the effect of two enzyms on 
the dissolved bodies. A 1 per cent solution of pectins from gentian 
root was gelatinized by a solution of pectase within 40 minutes, and 
also by limewater, sodium hydroxid followed by hydrochloric acid, 
neutral and basic lead acetates, ferric chlorid, magnesium sulphate, and 
ammonium sulphates, but not by sodium sulphate. The pectin was 
not reducing and was dextro-rotatory ([@]p>=+82.3°). Acidified water 
extracted a more dextro-rotatory body ([a@],)=+145.3' 
“#Ann. Chem. (Liebig), 1895, 286: 278. 
bIbid., 1895, 286: 292. 
¢Zts. Gacker-Ind. Bohm., 1894, 19: 101, throngh Chem. Centrbl. 1895, 66: 1, 833. 
a@J, pharm. chim., 1898, [6] 7: 473; 1898, [6] 8: 145; 1899, [6] 9: 281. 
‘Compt. rend., 1899, 128: 1241. 
