Crude hydrolysates

Glucose and Xylose Present in Crude Hydrolysates of Various Cellulosic Biomass by Batch or Continuous Process.183... 

Fig. 12. Fermentation of glucose and xylose present in the crude hydrolysate of corn fiber by genetically engineered Saccharomyces yeast strain 1400(pLNH32). The corn fiber hydrolysate was provided by Cargill, Inc. The major sugars present in the hydrolysate are glucose, Xylose, and-arabinose. Symbols solid square glucose solid circle xylose solid triangle ethanol open circle arabinose open triangle xylitol and arabitol open square glycerol...

It followed that the same epimerization probably occurred during acid hydrolysis of the Ginseng saponins. The chloro compound (10) was obtained from the ether insoluble fraction of the crude hydrolysate of the saponin mixture with cone. HCl. The ether soluble fraction of the hydrolysate was subjected to dehydrochlorination to give an 20-epimer of (11) named 20(S)-protopanaxadiol (26) (Chart 2), the structure of which was elucidated by correlating it with (13) as follows. The dihydro derivative (27) of (26) was oxidized to give a diketone (28) which was identical with the diketone derived from (13) via (16) 16, 17, 19). Crystalline substances (1) and (12) of the 20(R)-series were also readily obtained from the less soluble fractions of the hydrolysates of the saponin mixture and from the hydrogenated saponin mixture, respectively, while the corresponding 20 ( S)... 

As a result of this work, it was discovered that substance (11) undergoes another type of acid catalyzed ring closure on treatment with BF3 etherate at room temperature (22, 23). This affords a crystalline compound named isodehydropanaxadiol (29) in 28% yield, whose structure was deduced by mass and NMR spectroscopy. Compound (29) was also isolated from the crude hydrolysate of the saponin mixture with dilute mineral acid as one of the minor products. 

DCP and CPD esters of fatty acids (palmitic, stearic, oleic, hnoleic and linolenic) were detected only in the crude neutrahsed hydrolysates (Table 12.7). These lipophilic compounds (the main fatty acid was oleic acid) in neutrahsed hydrolysates form a layer on the surface that is easily removed by filtration and goes to the waste humins, so that in the commercial products obtained from the crude hydrolysate they may be present only in traces. 

Table 12.10 shows some examples of the detoxified hydrolysates. Today, decontamination is performed on the crude hydrolysate... 

The crude product is evaporated to dryness and then heated with a mixture of ethanol and sulphuric acid the cyano group is thus hydrolysed giving malonic acid, which then undergoes esterification to give diethyl malonate. 

The suspension of phenylacetamide may be further hydrolysed to phenylacetic acid by refluxing with stirring until the solid dissolves. The mixture becomes turbid after 30 minutes and the product begins to separate as an oil refluxing is continued for 6 hours, the mixture is cooled first with tap water and then by an ice-water bath for about 4 hours. The crude phenylacetic acid is filtered at the pump, washed with two 50 ml. portions of cold water, and dried in a desiccator. The resulting crude acid melts at 69- 70° it may be purified by recrystallisation from light p>etroleum (b.p. 40-60°) or, better, by vacuum distillation. 

Hydrolyse the acetyl-sulphap3Tidine by boiling it with 10 parts of 2N sodium hydroxide for 1 hour, and allow to cool. Precipitate the base by the addition of 50 per cent, acetic acid until the mixture is just acid to litmus (pH about 6 5) avoid a large excess of acid. Filter off the crude sulphapyridine, wash well with water, and dry at 90° to constant weight (about 12 hours any acetate formed will bo decomposed). The yield is 35 g. RecrystaUise from 90 per cent, acetone (5) the recovery of the pure compoimd, m.p. 190-191°, is about 80 per cent. 

Hydrolyse the 5 g. of 3-indoleacetamide by heating it under reflux for 4 hours with a solution of 6 g. of sodium hydroxide in 40 ml. of water. Cool to 5°, treat with decolourising carbon (if necessary), filter, render strongly acid with concentrated hydrochloric acid (pH about 1 5). Collect the acid which precipitates and dry it at 70° the crude acid weighs 4 5 g. Purify as above. 

AEBSF, an irreversible inhibitor of serine proteases, was found to completely inhibit MCA-hydrolysing activity in the concentrated crude culture filtrate at a concentration of 1 mM. We studied AEBSF inhibition of CinnAE at concentrations of 1 and 5 mM AEBSF and found activity was reduced to less than 1 % of that found in the uninhibited sample within 18 h of treatment. These results indicate that CinnAE has an active site serine residue. 

Crude dimethylaniline was being freed of impurities by treatment with acetic anhydride according to a published procedure [1]. However, three times the recommended proportion of anhydride was used, and the reaction mixture was ice cooled before addition of diluted hydrochloric acid to hydrolyse the excess anhydride. Hydrolysis then proceeded with explosive violence. 

The oxime was hydrolysed with aqueous sulfuric acid and the 2-butanone liberated was distilled out at 15 mbar from a bath at 110-115°C. Soon after release of vacuum and bath removal, the residue (crude hydroxylaminium sulfate) decomposed violently. 

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