1. It has been proved that 1-aspartic acid is synthesized from fumaric acid and ammonium chloride by yeast and no aspartic acid is synthesized in the absence of yeast or ammonia.
2. The best yield for the present is 75.599/a of the theoretical.
3. It is presumed that there are 2 mechanisms in reference to the synthesis of l-aspartic acid:
a) Fumaric acid+NH3 → l-aspartic acid
b) Fumaric acid+NH³ → l-aspartic acid succinic acid+NH³
Fumaric acid → succinic acid+NH³ → l-aspartic acid.

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1. The hydrogen ion concentration of cane molasses wort has been investigated by gas chain method for distillery purpose. It varies from pH 5.06-5.93 at 20° Bolling.
2. On heating or reservation, the pH diminishes 0.3-0.56.
3. The buffer capacity has been shown by electrometric titration curve.
4. The titrable acidities of cane molasses wort by electrometric method were 18-36c.c. of 1/1.0 n NaOH on 100c.c. of wort, and by ordinary indicator method using litmus paper were 20-35c.c. and when used phenolphthalein as an indicator were 36-74c.c. of the same.
5. It is observed that the cane molasses wort ferments with good results on the pH range of 3.5-6.0 and the optimal range is pH 4.0-5.0 by the yeast No. 396 of our laboratory which is the powerful and widely distributed species in this land.

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(1) The reduction potentials of acetylacetone, acetonylacetone, benzoylacetone, dibenzoylmethane and diphenyltriketone were measured with the dropping mercury cathode and the polarograph.
(2) In order to show the relation of reduction potentials of these compounds to their concentrations and hydrogen ion concentrations, the socalled theoretical values of R. P. were calculated by the Nernst formula of the reversible reduction type assuming two atoms of hydrogen taking part in the reduction, and were compared with the observed values at 25°C
π=0.05911/2logk'/[H'][Reducible compound]
EXPERIMENTS.
(3) Results of one part of the experiments were given in Fig. 5 (in original paper) showing PH reduction potential curves.
(4) For acetylacetone, taking the reduction potential (-1.097 V) of 1.033•10^-2 molar solution in the mixture as a basis of a calculation we found
logk'=31.09
For acetonylacetone
logk'=32.94
(-1.152 V for 1.0 10^-3 molar solution in the mixture [0.01 n HCl 0.1 n KCl]) For benzoylacetone
logk'=22.70
(-0.901 V for 1.0 10^-3 molar solution in the mixture [0.01 n HCl 0.1 n KCl]) For benzoylmethane
log k'=22.90
(-0.887 V for 1.0 10^-3 molar solution of 50% alcoholic medium [0.01 n HCl 0.1 n KCl]) For diphenyltriketone,
logk'=2.46 (-0.311 V for 1.0•10^-3 molar 10% alcoholic solution of 0.1 n NH₄Cl)
(5) 1-3 diketone, such as acetylacetone, benzoylacetone, dibenzoylmethane showed two distinct reduction potentials, due to enol- and ketoforms of these compounds. Further their enol forms were always more reducible than their ketoform.
(6) The negatifying effect of ethyl alcohol to the reduction potential of benzoylacetone was tested with the result that their R. P. changes linearly with the alcoholic concentration.
(7) The solubility of benzoylacetone to water was calculated to be 2.36×10^-3 mol per liter at 25°C.
(8) The group and orientation effects on the reduction potentials of ketonic compounds were found as the following.
1, 2 diketones were more reducible than 1, 3 diketones, for example:
Diacetyl and acetylacetone 0.802 V
Benzil and dibenzoylmethane 0.616 V
1, 3 diketone was more reducible than 1, 4 diketone, although the difference was much less conspicuous than the former cases.
Acetylacetone and acetonylacetone 0.055 V
Substitution of methyl group with phenyl group made R. P. more positive as mentioned in Part IV of our papers.
Benzoylacetone and acetylacetone 0.264 V
Dibenzoylmethane and acetylacetene 0.385 V
With regard to 1, 2 diketone and 1, 2, 3, triketone, contrary to our expectation, the former was more reducible than the latter, for example.
Benzil was more reducible than diphenyltriketone. This is much noticeable as diketones were far more reducible than monoketone as was reported in our previous paper.

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(1) The electrolytic reduction potentials of ortho-, meta-, and para-nitro-phenol were measured with the dropping mercury cathode and the polaro-graph.
(2) Analogous in the case of nitrobenzene_??_Shikata: Trans. Faraday Soc., No. 61 XXI 42 (1925)_??_the first stage of reduction was thought to be the system nitrophenol-nitrosophenol.
(3) Two waves of reductions were found in slightly alkaline solution, in which the easily reducible wave was proved to be due to the reduction of the undissociated nitrophenol and the second wave to be that of the ionised nitro-phenol. It should be noticed that negatively charged nitrophenol ion was more difficultly reducible than the undissociated molecule, and this was quite contrary to the case of pyridine, that pyridine ion (cathion) was more easily reducible than the undissociated pyridine molecule at the dropping mercury cathode.
(4) Reduction potentials of these compounds in the solutions of various hydrogen ion concentrations were compared with the calculated values from the following formula at 25°C, using the 1 n calomel electrode as the standard electrode.
π=-0.05911/2 log k'/_??_H_??_²_??_Reducible compound_??_
(5) For o-nitrophenol, taking the reduction potential (0.072 V) of 10^-3 molar solution in the 0.1n HCl containing 3% ethanol as the standard,
we found log k'=-2.57
and for ionised o-nitrophenol,
log k'=0.02.
For m-nitrophenol, by taking the reduction potential (0.043 V) of 10-² molar solution in 0.1n HCI as the standard, we found
log k'=-2.55
and for ionised m-nitrophenol,
log k'=3.46.
For p-nitrophenol, i.e. 0.090V under the same conditions as the former standard, we found
log k'=-0.95
for the reduction of free molecule and
log k'=5.51
for that of p-nitrophenol ion.
(6) Concordance of the observed values with the calculated values was tolerably good in the slightly acidic solutions but the former was much more positive than the calculated value in the alkaline solution for all nitrophenols.
(7) The following series may be given for the reducibilities of isomeric nitrophenols and nitrobenzene.
o-nitrophenol>m-nitrophenol>nitrobenzene>p-nitrophenol.
_??_College of Agriculture, Kyoto Imperial University ??

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