the isolation of levoglucosan from the enzymic hydrolysates of waxy

in water falls off rapidly from 0°to room tempera- ture. It has been difficult to secure sufficient repro- ducibility to give satisfactory quantitati...
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as fast as 20' as a t 25', but upon addition of chloroform to prevent freezing and cooling with solid carbon dioxide it appeared to be instantane-

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were constant. The products of this hydrolysis were dextrin B-lal and maltose, the yields being 62 and 30% of the weight of dextrin B-la, reOW. spectively. Dextrin B-lal rotated 146.0' in The only hypothesis that seems t o accord with water and had a reducing power by the Goreall of these results is the one suggested by Liebhaf- Steele method equivalent to 12% of t h a t of glusky,' that the reactive halogen is in the form of cose. On treatment with the amylase of Asperhydrate. If these hydrates contain a number of gillus oryzae, the reducing power of dextrin R-la1 molecules (of water, like the solid Cl2.6H20, they increased about sixfold and the rotation decreased could involve the large heat of formation required t o +3S0. This hydrolysate after fermentation to explain the large negative temperature coef- with yeast did not reduce Fehling solution and ficient of the reaction. There is, of course, was levorotatory. After removal of the yeast and ample evidence that the number of "icebergs" concentration of the solution, a solid was obtained D in water; in water falls off rapidly from 0' t o room tempera- by addition of ethanol; [ C U ] ~ ~-32' ture. yield, 4.2% of the weight of dextrin A . This It has been difficult to secure sufficient repro- solid was acetylated and from the resulting prodducibility to give satisfactory quantitative data, uct levoglucosan triacetate was isolated ; yield, and since this may take some time, it seems ap- 0.6% of t h a t calculated for levoglucosan on the propriate 1.0 publish the above preliminary re- basis of waxy corp starch; [ c Y ] * ~ D-65.5' in sults. CHClB (c, 1); m. p. 110-111°,7 (mixed m. p. unchanged). On deacetylation, levoglucosan was (1) 1% A. Liebhafsky, Chef#. Rev., 17, 89 (1935). obtained in pure crystalline form and characterDEPARTMENI OF CHEMISTRY ized. Levoglucosan was also obtained from 1-NIVERSITY UF CALIFORNIA BERKELEY, C:ALIF J. H. HILDEBRANDthe hydrolysate resulting from the action of the RECEIVED APRIL 15, 1946 amylase from Aspergillus oryzae on dextrin B - l a without prior fermentation. Isolation was efTHE ISOLATION OF LEVOGLUCOSAN FROM THE fected both by distillation and by fractional crystallization after acetylation. Further work will ENZYMIC HYDROLYSATES OF WAXY CORN have to be carried out to determine whether the STARCH 1,G-anhydro linkage is formed during enzymic Sir: Waxy corn ~ t a r c h ' *has ~ , ~been subjected to fission of the substrate or actually occurs in waxy the consecutive action of @-amylase, a-amylase, starch. (7) Zemplbn, Gerecs and Valatin, Ber , 73, 576 (1940) @-amylase,and an amylase prepared from AsperRESEARCH FOUNDATION gillus oryzae in order to obtain information on its CORNINDUSTRIES EDNAM. MONTGOMERY XEW YORK17, N.Y. structure. REGIONAL RESEARCH LABORATORY The starch, pasted a t 80°, was first treated with SORTHERN BUREAU OF AGRICULTURAL A N D INDUSTRIAL CHEMISTRY @-wheat amylase4 free from a-amylase and mal- AGRICULTURAL RESEARCH ADMINISTRATIOT tase. Dextrin A5 and maltose, the end-products U. S. DEPARTMENT OF AGRICULTURE of this hydrolysis, were isolated in yields of 49 and PEORIA5, ILLISOIS G E. HILBLRT 4870, respcctively. RECEIVED MARCH4, 1946 Dextrin A was then subjected to the action of a-malt-amylase,8 free from @-amylase and maltase, until no further increase in the reducing 6-CHLOROVANILLIN FROM THE CHLORITE OXIDATION OF LIGNIN power of the hydrolysate occurred. From this hydrolysate, dextrin B-1 was separated by the Sir: addition of ethanol to a concentration of 85% by I n a fundamental study of the reaction of lignin volume; after two reprecipitations the new dex- with sodium chlorite in acid solution, the original trin was dialyzed continuously against distilled filtrate from the preparation of holocellulose from water for nine hours. The liquor remaining after black spruce (Picea mariana) by means of sodium dialysis waij concentrated and the dextrin R-la chlorite in dilute acetic acid according to Wise and was recovered by precipitation with ethanol; co-workers' , 2 was investigated. The filtrate was yield, 44% of the weight of dextrin A ; [ff]"D further acidified with sulfuric acid and fraction+lCiO.l"' in water; reducing power 3.5 and S.006 ated. The steam lion-volatilc aldehyde fraction of that of glucose by Shaffer-Hartniann and Gore- was itlcntified as 6-chlorovanillin, colorless plates Steele methods, respectively. from ethanol melting a t 167-168'. (Anal. Dextrin %la was next submitted to the action Calcd. for CsH703Cl: C, 51.49; H, 3.78; C1, of @-amylaseuntil the rotation and reducing power 19.00; CH30, 16.63. Found: C, 51.34; H , 3.76; (1) Hixon and Sprague, I x d . E x g , Chem., 34, 959 (1942). C1, 19.19; CH30, 16.70.) The oxime, prepared ( 2 ) hfacMasters a n d Hilbert, ibid., 36, 958 (1944). by heating with a solution of hydroxylamine hy(3) Schopmeyer, Felton and Ford, ibid., 3 6 , 1168 (1943). (4) Hanes, Biochem. J . , 30, 174 (1936). ( 5 ) Cf.Haworth, Kitchen and Peat, J. Chem. SOL.,619-625'(1913). ( 6 ) Hanes, Ccn. J. Re.wnrch, 13B, 185-208 (1935).

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(1) Wise, Ind. Eng. Chem., Anal. E d . , 17, 63-64 (1045). (2) Wise, Murphy and D'Addieco, Paper Trade J.,122, No. 2, 35

(1946).