Free Organic Acid Research Articles

カレーに関する研究 ＩＩＩ 市販カレーかん詰の成分，特に遊離アミノ酸，有機酸，色と官能検査について

カレーに関する研究 ＩＩＩ 市販カレーかん詰の成分，特に遊離アミノ酸，有機酸，色と官能検査について

Phosphate-Solubilizing Potentiality of the Microorganisms Capable of Utilizing Aluminium Phosphate as a Sole Phosphate Source

Eight bacteria, each of the genus Bacillus, two actinomycetes, each of the genus Streptomyces, and six fungi, one each of the genus Penicillium and Chaetomium and four of the genus Aspergillus, were isolated on AlPO4-sucrose agar from a typical Indian lateritic soil (Typic Ochragualf). All of them were capable of solubilizing Ca3(PO4)2 to a higher degree than AlPO4. Bacillus subtilis (B-7655), LAB4, Bacillus sp., LAB5, Penicillium sp., LAF2, and Aspergillus spp., LAF3 and LAF4, were solubilizing Ca3(PO4)2 very efficiently, but AlPO4 to a lesser degree. Bacillus spp., LAB1, LAB2, LAB5, LAB6 and LAB7, Chaetomium nigricolor, LAF1, and Aspergillus spp., LAF5 and LAF6, were unable to bring detectable amounts of soluble phosphorus to solution from AlPO4. Except Chaetomium, all the other organisms produced free aliphatic organic acid in detectable amounts. The organic acids produced were oxalic, succinic, citric, and 2-keto gluconic acid. 2-Keto gluconic acid, singly and in combination with succinic or citric acid, accounted for higher solubilization. Amount of free organic acids in the growth medium was not directly correlated with phosphate solubilization.

パッションフルーツ (<i>Passiflora edulis</i> Sims) 果汁中のプロテアーゼ

The detection of proteolytic enzyme in the juice of purple passion fruit (Passiflora edulis Sims) was carried out and the properties of the crude enzyme preparations were studied.1. It has been found that the optimum pH of two types of proteases in the juice of passion fruit was 2.3 and 5.7, using casein as a substrate. The former was designated as PFP-I (Passion fruit protease-I) and the latter, as PFP-II.2. The maximum activity of PFP-I against temperature was 40°C and that of PFP-II was 50°C. The thermal stability of the enzymes in the solution of pH 6 was shown to be completely inactivated at 70°C and 60°C for PFP-I and PFP-II, respectively. The activity of the enzymes was comparatively stable over a pH range of 2 to 4. Although in the sodium citrate solution at pH 6 PFP-II was inactivated after freezing for 3 days, it was suitable for both of the proteases to be stored at 5°C.3. The activity of PFP-I was inhibited by incubation with Fe++, Co++, Pb++, Ag+, Zn++ and Hg++, but activated by Mn++, Sn++ and Cd++. On the other hand, that of PFP-II was reduced by Co++, Pb++, Ag+, Ca++ and Cd++, but slightly enhanced by Fe++, Cu++, Mn++ and Zn++.4. The maximum activity of PFP-I was in the acid pH region and was unaffected by various inhibitors such as PCMB, PMSF and EDTA. Therefore, PFP-I was estimated to be an acid protease. PFP-II was considered to be a SH-protease since its activity decreased markedly by some SH-reagents alone, being increased by cysteine.5. As fruits matured, the amount of juice per fruit increased, while free organic acid in the juice decreased. The specific activity and the total activity of the proteases were increased remarkably.

Studies on the thermal conditions of grapes. III.

1. With 3-year-old fruiting Delaware grapes, the effect of night temperature during the ripening process on the maturity and quality of berries was observed. Plants grown in pots were kept in the respective controlled temperature chambers of 15°, 22°, 28° and 35°C at night (6p.m. to 8a.m.), and placed outdoors in the daytime from August 6 to Sept. 10 in 1962.2. The time of maturity when the berries got full varietal specific color was as follows; August 27 at 28°C, Sept. 3 at 22°C, and Sept. 10 at 15°C, and berries never colored well at 35°C. The pigment content of the skin on Sept. 10 was in the order of 28°≥22°>15°>35°C.3. The soluble solids content of the juice(refractometer method) increased as the berries matured. The order of the content among the different temperature treatments was 28°>22°>15°>35°C on August 27, 28°=22°>15°>35°C on Sept. 3, and 22°>15° >28°>35°C on Sept. 10. The main kinds of sugars (paper chromatographic method) were glucose and fructose. They were of nearly equal amount at the time of maturity, though glucose was surpassed by fructose with a further advance of maturity.4. The free organic acid content of the juice (titration method) decreased rapidly with the progress of maturity, the trend being more marked in the treatments of the higher temperature. However, the content became nearly the same in all the treatments when the berries overripened. The main kinds of the free organic acids were tartaric acid and malic acid. The malic acid content decreased more rapidly than the tartaric acid with an advanced maturity and with an increased temperature of treatment.5. Fully matured berries of Delaware grapes sent from the chief producing districts of Japan were compared concerning their quality in relation to the average air temperature of nearly one month before harvest. As a result, the lower the temperature within a range of 22° and 28°C, the more delayed the maturity, while the more increased the pigment content of the skin, and the more abundant both the soluble solids and the free organic acids in the juice. Furthermore, berries produced in the region of the lower temperature such as Nagano contained less glucose than fructose, and berries which matured in Kagawa under the highest temperature had the least malic acid.

After‐Cooking Discoloration of Potatoes Role of the Organic Acids

SUMMARYStem‐ and bud‐end tissue from 41 samples of potatoes representing various degrees of after‐cooking discoloration were analyzed for organic acids content. The individual acids determined were glutamic, aspartic, pyroglutamic, malic, citric, orthophosphoric, oxalic, and one unidentified acid. The stem‐end tissue contained a lower concentration of all the acids except the unidentified one. The difference between the stem‐ and bud‐end was very large in some cases, notably for malic acid and citric acid.Examination of the data indicated a strong tendency for degree of blackening to be associated with low organic acid content. A statistical analysis of the data showed highly significant correlation of low citric acid, orthophosphoric acid, and oxalic acid content with blackening. Citric acid exhibited the highest degree of correlation, having an r value of 0.768.The significant correlation between low citric acid content and after‐cooking blackening was maintained in all but one case when subgroups of the samples were formed according to variety, crop year, and location grown. Of the three varieties studied statistically, Ontario and Katahdin showed correlation, whereas Kennebec did not.The interrelationships of iron, citric acid, and potassium contents were studied. Since there is always a large excess of citric acid over iron, it must be assumed that something prevents the citric acid from chelating the iron in blackening potatoes. The data indicate that potassium may be the main constituent playing this role. In the final analysis, the primary factor in the blackening phenomenon is probably the amount of free organic acid present.

遊離酸によるフェノール類並びにアミン類のアシル化の研究

Attempt was made on the acylation of free organic acid with phenol and aromatic amines by removing the water formed by the reaction through azeotropic distillation. Boric acid and p-toluenesulfonic acid were used as the catalytic agent in this reaction. By this reaction, phenyl acetate, phenyl propionate, phenyl benzoate, p-tolyl acetate, p-tolyl propionate, o-methoxyphenyl acetate, acetanilide, p-chloroacetanilide, and p-acetotoluidide were prepared. Acylation of free acid with phenol was effected by the addition of boron trioxide. Acylated products of alcohols and aromatic amines were obtained in a good yield by this method. Acylation of phenols with free acid is generally difficult and the present process is an interesting one in organic chemical reaction.

Effect of yellow mosalc virus on the free amino acid organic acid content of Phaseolus vulgaris L. leaves. A chromatographic study

Effect of yellow mosalc virus on the free amino acid organic acid content of Phaseolus vulgaris L. leaves. A chromatographic study

STUDIES ON THE ALKALI PURIFICATION PROCESS OF UNBLEACHED SULFITE PULP.

Hot alkali refining process of sulfite pulp was studied. 20 gms. of chlorinated pulp was refined in the caustic soda solutions at the consistency of 5%, with varying quantities of NaOH (4, 5, 6% against pulp) at varying temperatures (80°, 85°, 90°, 95° and 100°C) and for varying times (2 and 4 hrs) respectively. The waste liquor was subjected to potentiometric and conductometric titrations with normal solutions of HCl and NaOH. From analytical results the distribution of the original caustic soda was estimated, i. e., the combined alkali with weak acidic organic substance in the liquor, free hydroxyde in the liquor and the alkali retained in the residual fibre. Free organic acid was also estimated, when the amount of soda was insufficient. The organic matter involved three kinds of organic acid whose dissociation constants were in the orders of 10-4, 10-8 and 10-10 respectively.The amount of organic matters dissolved in the waste liquor was also estimated and the ratio with combined Na was calculated. The ratio was approximately 4.5 and the mean equivalent weight of orgainc matters was concluded to be 100 - 130.

On the Caustic Soda Boiling of Plant Bast in the Preparation of Japanese Native Paper

Refiued bast of “ Kozo” (Sirokawa) was heated at 100°C with varying quantities of caustic sod (115% against bast) for varying times (0.55.0 hrs) The waste liquor was subjected to conductonietric and poteutiometric titrations with normal solutions of hydrochloric acid and sodium hydroxide respectively. From the analytical results the distribution of the original caustic soda was estimated, i.e. the combined anlkali with weak acidic organic substance in the liquor, free hydroxide, in the liquor and the alkali retained in the residual bast fibre. Free organic acid was also estimated, when the amount of soda was insufficient. Organic matters dissolved in the liquor, was also estimated, and the ratio with combined alkali was calculated. The ratio was approximately equal to that of one hexose group against one NaOH molecule, and was almost independent of the amount of soda used and the time of boiling. Orgainc acidic substance seems to be composed of mixtures of acids, the dissociation constants of which lie between 10-510-6 and 10-810-9.