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The division error of sample, the accuracy of analytical method, and the personal error of analyst were examined with the Kjeldahl method for determining nitrogen in tea.The division error was compared with the accuracy of analysis, the former was larger 1.5, 1.1, 0.3 times than the latter when the sample was divided with the original size, divided after pulverized and not thoroughly mixed, divided after pulverized and well mixed, respectively.The accuracy of analysis was computed as C. V. 0.6%, but the personal error of analyst was surprisingly large, and it might contain any systematic error.The error accompanied with a single determination by an analyst was C. V. 2.02% and that with a mean value of double determinations by an analyst was C. V. 1.97%.By correcting the addition of catalyst and digestion time, the following operation is decided as the official method for determining nitrogen in tea.Weigh 100 mg. of pulverized tea into a 100-ml. digestion, flask, add 1.5g. of the mixed catalyst (CuSO4 I : K2SO4 9) and 3 MI. of conc. sulfuric acid. Digest the content on an electric heater or gas burner. Continue heating 1.5-2.0 hours after the color of content turned transparent blueish-green.Cool, dilute with water, and make alkaline with 30% caustic soda solution. Distil the whole content with steam for 10 minutes, catch the evolving ammonia into 10 ml. of N/25 sulfuric acid. Titrate the N/25 sulfuric acid with N/25 caustic soda solution by adding 1-2 drops of the mixed indicator (a mixture of equal volume of 0.2% methyl-red alcohol solution and 0.1% methylene-blue alcohol solution) until the reddish-violet color disappeared.

A microdetermination of nitrate nitrogen in the tea leaf was investigated colorimetrically and the following method was established.Treat the hot water extract of tea with basic lead acetate and ammonium hydroxide (pH 9). After removed the excess Pb with Na2HPO4, add Amberlite IR-120, stir occationally for about 1-2 hrs., and filter the solution into a 50-ml. erlenmyer flask. Add 5 ml. of about 2 N ammonium hydroxide, 0.5ml. of 1 % manganous chloride, and 0.2 g. of zinc dust successively. Stopper the flask and agitate for about 20 minutes on a magnetic stirrer. Filter the solution, acidify the filtrate (pH 1-3) with concentrated hydrochloric acid dropwise and develop the color with 0.3 g.of Griess-Romijn reagent on a water bath (35°C) for 10 minutes and make to 50 ml. After standing an hour, measure the absorbancy of the colored solution at 522 mμ with a spectrophotometer.The recovery of added nitrate nitrogen and the coefficient of variation of this determination (tea infusion) were 98.4% and 4.03% respectively.

A new microdetermination of caffeine in the tea leaf by paper electrophoresis and ultraviolet absorption spectrophotometry was investigated.The method was as follows : Moisten powdered tea (0.5g.) with a 0.5 ml. of 5% Na carbonate solution ; extract with chloroform for 2-3 hrs. in the extracting apparatus.Transfer the extract to a 25-ml. volumetric flask and make to volume with chloroform.Subject a 0.05-0.1 ml. of the chloroform solution to paper electrophoresis (buffer solution, M/100 Na borate; voltage, 600 V.; current, 0.6-0.9 mA./cm.) for 3 hrs. After drying the paper, discriminate the position of caffeine by the aid of ultraviolet light as a dark spot. Cut the paper strip 2×3 cm. in this position and elute with hot water through a glass siphon into a 5-ml. volumetric flask and make to volume.Transfer an aliquote of this solution into 1 cm. quartz cell and measure the absorbancy at 272.5 and 305 mμ by a spectrophotometer. Estimate the absorbancy at 272.5 mμ due to the impurities of filter paper from the correction chart. Subtract the estimated value from the absorbancy at 272.5 mμ of the sample solution to obtain a corrected absorbance value of caffeine, then determine the concentration of caffeine from the calibration curve.This method was possible to determine as little as 10-40 μg. of caffeine in a 0.05-0.1 ml. of solution without a tedious procedure. The accuracy and time of analysis were almost the same as the semimicro method which was already reported by the authors.

Data are presented showing the variation of the flavanolic constituents of tea leaves at the positions in plucked shoots and on the stages of growth under various seasons.For this investigation the following samples were used:(a) Crops harvested at interval of 3-5 days throughout flush. (b) Shoot of four types, i. e. two leaves and a bud, three leaves and a bud, three leaves and a bud remo-ved coarser part and soft triple banjhi. (c) Component parts of shoots.(-)-Epicatechin gallate, (-)-epicatechin, (-)-epigallocatechin gallate and (-)-epigallo-catechin in the above, samples were determined by paperchromatographic method and further proportional variations of flavanolic constituents in (b) and (c) were observed.The results were as follows : From the beginning to the end of flush, the decreasing of (-)-epicatechin gallate and the increasing of (-)-epigallocatechin were characteristic of variation. The relatively earlier pluckings, especially in the second season were rich in (-)-epigallocatechin gallate. Younger shoots and leaves were rich in galloyl flavanols and poor in free flavanols than more developed ones. The differences of the total content were not always definite except low value in banjhi and the fourth leaf. Stem was distinctly poor in flavanols except (-)-epicatechin. The samples of the second or the third season contained more flavanols than that of the first. Especially galloyl flavanols were accumulated in midsummer.It is concluded that the most notable figures of variation with growth are the decreasing of galloyl flavanols and the increasing of (-)-epigallocatechin, so long as the shoot is developing or the leaf is expanding.

A method for the quantitative determination of flavanols in tea leaf and green tea is described. Separated flavanols on two-dimensional chromatogram are revealed by spraying dilute diazosulfanilic acid solution and eluted by hot water. To these eluates is added diazosulfanilic acid buffered with sodium acetate and after sufficient color development the absorbances of them are measured spectrophotometrically.

As a substitute for the Lowenthal method for the determination of tea tannin, a colorimetric method using Mitchell's ferrous tartrate reagent was investigated.The reagent consisted of FeSO4 . 7H2O (100 mg.) and Rochelle salt (500 mg.) in 100 ml. of water. Tea tannin and ferrous tartrate produced a reddish violet color, having a maximum absorption at 540 mμ, which was most intensive in the buffer solution of pH 7.5. The absorbance of the colored solution was kept constant for 4 hours, and a slight decrease in absorbance was observed with the temperature rise of 20◊. Since the individual catechins gave different coloration and intensity with ferrous tartrate, the amount of tea tannin adopted was calculated by the Lowenthal method.The recommended procedure is as follows: The sample solution containing tea tannin is prepared by extracting powdered tea (100 mg.) with water (100 ml.) in a boiling water bath for 30 minutes and filtering. Five ml. of the sample solution and the same quantity of the reagent are transferred into a 25-ml. volumetric flask and filled to the mark with Sorensen's phosphate buffer (pH 7.5). Then the absorbance is measured at 540 mμ against a blank solution substituting water for the reagent, and the amount of tea tannin is determined from the calibration curve.The variation coefficient of the determination was about 2 %.By the continuous variation method, it seemed that an Fe reacted with one molecule of gallic acid, two of (-)-epigallocatechin, and three of (-)-epicatechin respectively.

A method for the quantitative determination of flavanols in tea leaf and green tea is described. Separated flavanols on two-dimensional chromatogram are revealed by spraying dilute diazosulfanilic acid solution and eluted by hot water. To these eluates is added diazosulfanilic acid buffered with sodium acetate and after sufficient color development the absorbances of them are measured spectrophotometrically.

Tea seeds were sawn in sand in the dark or in the light. After germination the chemia constituents of the seedlings were compared.Caffeine, a specific component of tea, was proved to be not contained in the root and seed, nevertheless it was contained 1.8-3 times as much in the leaf and stem grown in the dark as in the light. It was confirmed that the caffeine synthesis did not necessitate sunlight.The nitrogenous constituents were contained most abundantly. in the leaf, and more less in the root, stem, and cotyledon in the decreasing order.As for the composition of nitrogen fractions, one-third of nitrogen in the leaf or stem in the light, half of nitrogen in the leaf in the dark and in the root in the light, two-thirds of nitrogen in the cotyledon in the dark or light, and three-forths of nitrogen in the stem and root in the dark were in soluble form. The dark treatment generally increased the soluble nitrogen/total nitrogen ratio in the nitrogen fractions. And the caffeine-free soluble fraction was remarkably variable in the soluble nitrogen fractions.From the calculation of the weight of each fraction per seedling, it was presumed that the amount of nitrogen in each fraction in the seedling grown in the dark was nearly equal to that of the corresponding fraction in the seed, while in the light one-tenth of the soluble nitrogen in the seed and one-third of that migrated into the seedling and transformed to the caffeine nitrogen and insoluble nitrogen respectively.Sixteen spots of amino acids and amides except unidentified ones were detected by paper-chromatography. Theanine, a specific amide of tea, was contained in a very small amount in the seed, but after germination appeared in every part of seedling grown both in the dark and in the light, and especially occurred in the root most abundantly. Alanine, aspartic acid and arginine were also found in every part in all cases, and the former two were contained abundantly in the leaf and stem, the latter in the root respectively. Glutamine and threonine were presumed to be prevailing components and the former was found in large quantity in the stem, the latter in all parts of seedling grown in the dark. Asparagine had a trend to be contained abundantly in the dark.As for catechins, the leaf in the light contained (-)-epigallocatechin and its gallate, (-)-epicatechin gallate. (±)-gallocatechin, gallic acid and theogallin. The former two occurred more abundantly. The light→dark treatment reduced catechins, especially (-)-epigallocatechin gallate was decreased.

1. The yield of tea leaves was influenced by a slight variation of the plucking time, so, it does not show the correct value unless it is adjusted.2. The yield was observed that it was closely correlated with the maturity (indicated by the ratio of bhanji shoot) and the number of shoots by a uniformity trial of sampling on the tea garden of the variety "Tamamidori".3. The observed values of dry and fresh yield were adjusted by the maturity and number of shoots, both at mean and at the presumed best plucking time, as well as the effect of adjustment was tested by the reduction of variance or coefficient of variation of the sample.4. The adjustment by the multiple regression of maturity and number of shoots proved more effective than by the single regression of each. The reduction of coefficient of variation by the adjustment is shown in the following table.From the result, the adjustment by the number of shoots was more effective, compared with each of the single regressions. However, some kinds of experiments may need not any adjustment by the number of shoots, or may need by other factors, but no case would be expected in which the yield would not be adjusted by the maturity5. The estimated yield with its confidence limits at the presumed 'best plucking time was calculated, and this figure would be recognized the most reasonable value in this sample.

The carbohydrates in the tea leaves were divided into eight fractions. The component sugars of each fraction have been investigated by two-dimensional multiple development paper chromatography. The following sugars were detected as the components: glucose, fructose, sucrose and two unknown oligosaccharides as free sugars; glucose, rhamnose, galactose, and arabinose as the component of glycosides; glucose, galactose, arabinose, xylos e, mannose, rhamnose, galacturonic acid and four unknown uronic acids as the component of water-soluble polysaccharides; ribose and desoxyribose as the component of nucleic acids; and glucose, galactose, arabinose, xylose, fructose, rhamnose, glucuronic acid and another unknown uronic acid as the component of hemicelluloses.

It was an well-known fact that the ordinary tea leaves contained about 5% of nitrogen in spring and about 3% in summer, but the reason why the depression of the nitrogen content occurred during these seasons has not yet been confirmed.With the purpose of solving this problem, some experiments were performed from 1952 to 1954, by comparing summer crops one of which harvested with regular plucking, the others had not been plucked or checked the flushing with MH-30 spraying in the preceeding season.In these experiments, the yield and nitrogen content of the regularly plucked tea bush decreased in the order of 1st, 2nd, and 3rd season, and tannin content varied in the reverse direction as many chemical analyses had shown previously.The bush unplucked in the preceeding season produced lower yield and the crop was poorer in nitrogen content and higher in tannin than the control. But, as the total amount of the chemical component harvested in the crop depended upon the yield, both nitrogen and tannin deprived were larger in the control.The bush which was checked its flushing by MH spraying in spring could not produce so rich leaves in nitrogen in summer as the control bush had produced in spring.The chemical analyses of mature leaves also showed the fact that the nitrogen did not seemed to be reserved in the leaves during the season when the flushing had been checked.As the results of 3-year's experiments, any proof for explaining the reason why the summer crop had lower nitrogen content was not obtained from the point of view of nitrogen absorbing. period from the tea root.

For establishing the sampling method of foliar analysis by which the tea plant was diagnosed, the variations of inorganic constituents (ash, N, P2O5, K2O, CaO, etc.) of tea leaves in the year, region, variety, and development in the first. season were determined.The annual variation : At the middle of every month, the mature leaves of two varietics (Benihomare and Tamamitlori) wcre analyzed. These constituents generally reached high levels in autumn, then declined and kept constant, lcvels throughout winter season.The regional variation : From ten tea experiment stations in the principal tea-producing prefecturesin Japan, the winter old leaf, spring young leaf, and spring old leaf of Yabukita variety were collected and analyzed. The regional variation of soil constituents was very large, i. e., the max. values of P2O5 and MnO were 60 times and 20 times larger than the min. ones of the respective constituents. On the leaf constituents, the variations of N and ash were small, while those of MnO and CaO were large. It was better to adopt the winter old leaf as. the sample for analyzing N or CaO owing its low regional variation, and for analyzing K2O or MnO any kind of leaves would be adopted. Significant correlations were observed between N, IMO and P2O5 contents of soil and those of leaves. The contents of these three constituents in soil influenced upon those of young spring leaf in the case of the former two, and upon that of winter and spring old leaves in the case of the latter one. The tea plant whose old leaf lost larger N content during the period from winter to spring flushed new shoots which were poor in N in spring. The loss of N above-mentioned seemed to be a factor indicating the nutritional status of the plant. Concerning the content of constituents, N, P2O5 and K2O were most abundantly contained in young leaf, CaO and MnO more in old leaves, and ash least in winter old leaf.The varietal variation : The three kinds of leaves as the same as in the investigation of regional variation were sampled from twenty tea varieties cultured in the field of our station. The analytical results showed that the varietal variations of N and ash were small and the coefficients of variation did not exceed 10%, whale those of MnO and CaO were large as in the case of regional variation. So many significant correlations among the constituents did not exist as in the regional variation, as there were some varieties having special composition of constituents.The variation in the development of young leaf : The constituents of young leaf of Tamamidori variety were determined every five days in the first season. The result indicated that the inorganic constituents such as P2O5, K2O, and CaO were kept at fairly constant levels during a wide range of maturity of leaf. It is unnecessary to pay so much attention for sampling tea leaf as in the analyses of organic constituents.

(1)ベーパークロマトグラフィによる茶葉タンニンの分離方法を設定するために,展開剤の選定,展開温度,展開剤の含水量について試驗した。展開されたタンニンは硫酸第二鐵によつて呈色させた. (2) その結果,茶葉タンiニンには供試した7種の溶剤の中,η一ブタノールの水飽和液が最も好結果を示した. (3) この方法によつて茶樹品種C-8, U-17,藪北の3種の茶葉タンニンの比較を行つたが,藪北は他の2種しとはタンニンの組成が違うことが分つた.

Throughout the second and third plucking seasons in 1955, the growth of shoot, yield of leaves, qualities of tea, and amount of chemical constituents in the leaves were surveyed, using three green tea. varieties (Yabukita, Miyoshi, Natsumidori, and Tamamidori) and one black tea variety (Benihomare).The relation between the maturity of leaves, which was indicated by the ratio of bhanji leaves and called in Japanese as Debirakido %, and the above-mentiored observed data was investigated and it was proved that the best plucking time could not be decided after the.leaves had exceeded over 90% of Debiraki in every tea variety.

With the determination of tea tannin by the Lowenthal method and the colorimetric method using ferrous tartrate, the extraction rates of tannin in the green tea with several solvents, the temperature effect on the extraction of catechin fractions, and the reduction of tannin content by the filtration of infusion were investigated.The preparations of determining solutions were carried out as follows: in the Lowenthal method, 500 mg. of powdered tea was infused with ca. 70ml. of hot water for 90 min. and in the colorimetric method, 100 mg. of sample was treated in the same way for 30min. After cooling, both infusions were filled up to 100 ml. and filtered, then the tannin content in the filtrates was determined.Tea tannin, especially ester-type catechins, most of which consisted of (-)-epi-gallocatechin gallate, were less extractable in hot water than in aq. acetone and other organic solvents.The infused tannin content increased as the extraction temperature rose till 60°C., then reached almost a constant level.At a low temperature, the extraction rate of ester-type catechins was remarkably small, however, at a high temperature (over 80°C.)pyrogallol-type catechins seemed to be decomposed yielding gallic acid and (±)-gallocatechin.The tannin content was considerably lower in the first 20 ml. of filtrate through. several filter papers than in the succeding 20-40ml.

Data are presented showing the relationship of flavanolic constituents to tea leaves to the position in plucked shoots and to the stages of growth at various seasons. The results indicate that with the development of tea leaves, there is an increase of (–)-epigallocatechin and decrease of (–)-epigallocatechin gallate and (–)-epicatechin gallate. This suggested that past common data on the variation of tannin content is not always sufficient for such α subject.

For the determination of individual flavanols in tea leaf or green tea a paperchromatographic method is proposed from results of investigations of various estimating, conditions.A weighed sample (1-2g. of fresh leaf or 100-200mg. of powderd tea) is extracted with acetone and an aliquot of the solution (corresponds to ca.2 mg. of fresh leaf) is subjected to chromatography. Two-dimensional ascending chromatography is carried out on 23×19cm. Whatman No.1 paper using phenol-water (3:1) and a butanol-acetic acid-water mixture (4:1:2). The dried chromatogram is sprayed uniformly with a minimum volume of diluted diazotized sulfanilic acid.The preparation of diazotized sulfanilic acid is as follows:To a solution of sulfanilic acid in 1.75% hydrochloric acid (0.5%) is added an equal volume of 0.5% aqueous sodium nitrite solution. This reagent is used for the preliminary revelation of flavanols after being diluted to 1/5-1/10 concentration with deionized water and for color reaction of the estimating solution after mixing with 2.5 volume of sodium acetate buffer (2%).The detected spots are cut out and the flavanols are eluted from the paper with 9ml. of hot water. To these eluates is added 0.35ml. of diazosulfanilic acid solution buffered with sodium acetate and make up to 10ml. with water. The colored eluates are placed in a bath at 35°C. for 30 min. and after being cooled to room temperature the absorbances at 420mμ of them are measured spectrophotometrically. The calibration curve by use of each standard flavanol is available for the determination.This method will ensure the determination of 10-50μg. of catechins with 1.5-9.3% of coefficients of variation.

In 1959, the experiment was designed by combining the gibberellin spraying and manuring, and each plot was given with the same treatment through all plucking seasons.The results of experiment were as follows: the growth rate of tea shoot sprayed with gibberellin was faster, and in 1st, 2nd, and 3rd plucking seasons the amount of growth per day were 3.9, 3.9, 6.3 mm. in the sprayed plots and 2.5, 2.2, 3.5 mm. in the unsprayed plots respectively.The number of shoot and number of leaf were not affected by gibberellin spraying, and both the sprayed and unsprayed shoot increased one leaf in 5 days in 1st season, 4 days in 2nd season and 3 days in 3rd season.The yield and weight of shoot were larger in the sprayed plots and the former of whole shoot and of P+3L showed an increase of 8% and 5% over the unsprayed plots.Of the chemical constituents, chlorophyll was reduced which coincided with the results of the preceding experiments, but total nitrogen, caffeine, tannin, and crude fibre contents showed no significant difference between the sprayed and the unsprayed.The qualities of black tea made with the sprayed leaves were better than those of the unsprayed, but the increase of the plucking cycle in a year could not be expected.

A tentative method for paper chromatographic study of tea catecbins was established after several meetings of tea chemical engineers.The procedure is as follows :1. Preparation of sample solution.Add 10 c.c. of boiling water to 1g. of sample, keep in a boiling water bath for 5min. Drop 0.02 c.c. of this infusion on the original point of filter paper.2. Two dimensional development.Filter paper : Toyo No.3, 20×20cm.Developing temperature : 20°C (Unless 20°C. adopted, describe the temperature used.)Original point of development : Near a corner of the paper 2cm from either edge.The-first run :Developing solvent : Phenol containing 25% (vol.) water.Developing distance : Reach the solvent front 2cm, below the upper edge of the paper.Developing direction : Along the fibre arrangement, of the paper.After the first run is over, dry the paper in an electric heater, cut off the contaminated part of the paper by phenol front. The second run :After standing one night, perform the second run.Developing solvent : n-Butanol : acetic acid : water (4:1:2 vol.).Developing distance : Same length as the first run.Coloring reagent :A 1% solution of MOHR'S salt plus same volume of methanol.

The tea leaves have been sampled during the rapid-growing period of the shoots. A slight difference of harvesting time had susceptible influence on the maturity of the leaves, as well as on their physical and chemical properties. As it is verey difficult to decide the best plucking time technically, the calculation of chemical constituents in the tea leaves is not available unless the maturity of the leaves is adjusted to a standard level. Then, the relation between the chemical constituents (tannin and total nitrogen) and the maturity of the leaves (indicated by the ratio of the bhanji shoot) was researched by a uniformity trial of sampling of the variety "Tamamidori" on the tea garden.In regard to the chemical constituents, no adjustment by the maturity of leaves was necessary for total nitrogen, as far as these surveys were concerned, but it is easily presumed that some adjustment to this constituent would be required if the sampling conditions would be varied. Whereas, an adjustment by the maturity of the leaves was necessary for tannin, even in the case.of these samples having such a narrow range of maturity.For the most reasonable tannin value, the data were adjusted by the maturity of the leaves at the best plucking time and the confident limits of the adjusted values were also calculated.The sample size for obtaining a balanced sampling to the accuracy of the chemical determination of tannin and total nitrogen was calculated; it was found to be satisfied with 10 samples when the maturity of the sample did not exceed so far from that of the leaves at the best plucking time.

The sample form of tea shoot for analyzing the chemical components was investigated. In the 1st plucking season 1956, the tea shoot of variety "Tamamidori"was plucked (P4-3L) in 10 plots on the same day, divided into individual leaves, and analyzed the total-N and tannin contents.By comparing the coefficient of variation (C. V.) of analytical values of respective. samples, it was proved that the C. V. of whole plucked shoot was the smallest among others, and if the tannin value was adjusted by the maturity of shoot (Debiraki-do), its C. V. was reduced less 1/2 than that of the unadjusted.In the case of day-after-day sampling of the same variety in the 3rd plucking season, the variation of chemical contents of individual leaves was complicated, but in the whole plucked shoot, not separated into parts, the total-N content kept a stable level during 20-70%o of Debiraki-do, and tannin content could be easily adjusted by a primary regression equation upon Debiraki-do.From the result of these two experiments, any advantage could not be recognized by dividing the shoot into individual leaves.The ratios of chemical content of individual leaves to whole shoot were as follows: the 1st leaf '117 (total-N), 125 (tannin) ; the 2nd leaf 104, 108 ; the 3rd leaf 93, 89, and these figures were nearly constant in spite of the maturity of shoot and the plucking season.

A study was made of the enzymic oxidation of various flavanols, alone or in combination of them. The results confirmed that the oxidation of mixtures containing the catechol flavanols and (–)-epigallocatechin developed remarkable red colors. In addition to the current information some other courses producing the theaflavin-like substance were found. Furthermore it was suggested that there exist several kinds of substance occupying the similar position on the chromatogram as spot Y of Roberts.

For determining chlorophyll-a and -b in made tea or tea leaf, the following experiments were performed.1. To extract chlorophyll completely from made tea, three or more successive extractions with acetone containing 10% water were necessary, but when the sample was fresh leaf, undild. acetone should be used at the first time and never had to give heating before extraction, unless otherwise the decomposition of chlorophyll could not be avoided.2. By circular paper chromatography of the acetone extract with the mixed solvents of petroleum ether : benzene (4 : 1) or benzene : carbon tetrachloride : ether (10: 10 : 1), chlorophyll-a, -b, carotenoids and two unidentified pigments were separated clearly, and these pigments could be eluted by ether.3. The ether solution of chlorophyll was estimated by measuring the optical density with a spectral monochromate near 660 mμ. The measurement was greatly interfered by the unidentified pigments but not by the carotenoids.4. The two unidentified pigments which were contained in an appreciable quantity in made tea seemed to be the degradation pro-ducts of chlorophyll-a, and -b whose absorption spectra agreed well with those of phaeophorbide-a, and -b and the color was greyish green and yellowish green respectively.5. In Gyokuro, some amounts of chloro-phyll-a and -b were contained, but in Seneha and pan-parched tea a trace of chlorophyll-a and a small amount of chlorophyll-b. were merely detected and in black tea both chlorophyll-a and -b completely disappeared.It was presumed that the fresh green color of Gyokuro and.Tencha was due to the undecomposed chlorophyll but the dark green color of Sencha and pan-parched tea was characterized by the phaeophorbide-like pigments.

The content of the flavanolic fractions, (-)-epicatechin gallate (I), (-)-epicatechin (II), (-)-epigallocatechin gallate(III), (-)-epigallo-catechin (IV), (+)-gallocatechin (V), (+)-catechin (VI), gallic acid or (-)-gallocatechin gallate (VII) and several other polyphenols was compared in the leaf of tea plants which belonged to Assam variety (A), China variety (C) and its Japan jat (N), and their mutual hybrids.The tested clones were Akane (AN), Benitachiwase (AN), C17 (C), Benikaori (AN), Tadanishiki (A), Hatsumomiji (AN), Benihomare (A), Satsumabeni (NA), and Benifuji (AC) used for black tea, Yabukita (N), Z1 (N), Y2 (N), U4 (N), Horyoku (A), Karabeni (C), Tamamidori (N), Mie 260 (N), Asatsuyu (N) and Miyoshi (N) used for green tea. The tea plants signatured with A and C are raised in Japan from the seed of Assam and China plants. Further Caucasian, Taiwan indigenous (A), P1 (C), S52 (N), S6 (N), Koro, Seishin (C), Boh (A) and Ceylon (A) were chosen on the account of characteristic features or differences of origin.During the first, second and third flushes, shoot of each clone which consisted of three leaves and a bud was plucked from a labeled bush grown in this station and was subjected to the estimation of each flavanolic fraction. While hand-made black tea was prepared from these materials and tasted with the liquor characters.The clones for black tea were richer in all flavanolic fractions, especially in (III) and (I)+(III) except (II) than those for green tea. The latters showed higher proportion of the free flavanols (II)+(IV), although they were rather inferior with absolute quantities of (IV) to the formers. Tasting of black tea indicated a considerable correlation between the scores for color and the galloyl flavanols content (I)+(III).The relative proportion of the four predominant flavanols (I), (III), (III), (IV) to the totals (I)+(II)+(III)+(IV) in these samples were as follows : The first crop, (I) 11.7-23.1%, av. 16.7%; (II) 3.6-13.9%, av. 8.7%; (III) 39.1-65.1%, av. 51.2% ; (IV) 13.4-34.6%, av. 23.4% ; The second crop, (I) 13.0-25.9%, av. 18.7% ; (II) 4.5-10.9%, av. 7.1% ; (III) 46.5-63.2%, av. 56.9% ; (IV) 11.5-28.0%, av. 17.3% ; The third crop, (I) 10.1-20.4%, av. 15.6% ; (II) 3.9-11.6%, av. 6.0% ; (III) 43.0-66.8%, av. 58.8% ; (IV) 13.8-32.6%, av. 19.6%.Several clones, i.e. Y2, Seishin, Koro, Benikaori, P1, Caucasian differed considerably from average in flavanolic composition. However most clones resembled each other in their make-up.(+)-Catechin (VI) was not detected with only several clones. Gallic acid or (-)-gallocatechin gallate (VII) was found in certain clones.The plants related Assam variety showed generally higher total flavanol content than the Chinese and Japanese. However the varietal difference in relative proportions of the various fractions was not obvious.

茶葉並びに茶種子中に含まれる遊離糖のうち,第1報に未詳のオリゴ糖として報告した2種のものについて,その構成糖を調べた. その一は(スポットb糖)オルシン反応陽性で, n-ブタノール・酢酸・水(4:1:1)の展開ではラフィノースとほぼ似たRF値を示すが, n-ブタノール・ピリジン・水(3:2:1.5)の展開では明らかにRFは低い構成糖はラフィノースと同様にガラクトース,グルコース,フラクトースの3種であるが,ラフィノースよりもガラクトースの含有比が大ぎい. また,いま一つの糖(スポットa糖)もオルシン反応陽性で,上記両種の展開剤によりいずれもスタキオースに近いRF値を与えるが,構成糖はスタキオースの3種に対し,ガラクトース,グルコース,フラクトース,キシロースの4種から成り立つている. なお,最近CARTWRIGHT及びROBHRTS(2)は製茶の熱水浸出液より,フェノール・酢酸・水(80:2:18)とブタノール・酢酸・水(4:1:2.2)の2次元クロマトグラムによつて,グルコース,フラクトース,蔗糖の他にアラビノース,リボース,ラムノース,ラフィノース,マルトースを検出したと報じているが,この試料はおそらく紅茶と思われるので,製造工程中殊に醗酵操作などでアラピノース,リボース,ラムノースなどが遊離となる可能性も考えられる.また,ラフィノース,マルトースについては,彼等の使用した展開剤では他の二糖類,三糖類が,ラフィノース,マルトースとして同じ位置を占める懸念も多いと述べている. この実験に用いたスタキオースは,東京大学応用微生物研究所丸尾文治助教授より恵与せられたもので,厚く謝意を表する.