Kunijiro Yoshitama

Flavonoids in the leaves of twenty-eight polygonaceous plants

Flavonoids in the leaves of twenty-eight species belonging to the Polygonaceae were studied. Thirty-three kinds of flavonoids were isolated, and eighteen kinds were obtained as crystals. Quercetin glycosides were commonly found in the family. In the quercetin glycosides, 3-O-rhamnoside was most frequently found: 3-O-glucuronide is also distributed widely. Myricetin glycosides were rare. Methylated flavonols were found in some species of the sectionsEchinocaulon andPersicaria. Eleven kinds ofC-glycosylflavones were found in the present survey, andC-glycosylflavones were distributed in all species of the genusRheum and in almost all species of the section Tiniaria.Rumex Acetosella andPolygonum suffultum are exceptional, the former contains flavone glycoside and the latterC-glycosylflavones only, as main components.

Chromatographic and spectral characterization of 3′-glycosylation in anthocyanidins

Abstract The caffeyl ester of cyanidin 3,7,3′-triglucoside was isolated from red petals of garden cineraria, Senecio cruentus . Chromatographic and spectral characteristics of the anthocyanin as well as the products of deacylation and partial hydrolysis are described. The results with this pigment and a similar one based on delphinidin show that anthocyanins having a sugar residue at the 3′(or 5′)-position are characterized by the position of the visible max and by the high values for E 440 / E vis max and E UV max / E vis max when compared with other glycosides.

Concerning the structure of cinerarin,a blue anthocyanin from garden cineraria Studies on anthocyanins,LXVI

A purplish-blue anthocyanin was isolated from the flower of garden cineraria (Senecio cruentus DC.). The pigment retains a stable blue color within the range of pH 3.5-7; but it differs in other characteristics from the known blue anthocyanins. This pigment is composed of delphinidin, glucose and caffeic acid in a molecular ratio of 1∶3∶2, respectively and is tentatively called “cinerarin”. The blue flower color of cineraria seems to be manifested solely by cinerarin, and it becomes likely that the caffeic acid involved in the molecule plays an essential role in the blueness of this pigment.

Blue and purple anthocyanins isolated from the flowers ofTradescantia reflexa

Blue and purple anthocyanins were isolated from the flowers ofTrandescantia reflexa. Both anthocyanins retain their specific colors firmly in the range of pH 3.5-7. Structural studies have revealed that the blue and purple pigments are tricaffeyl 3,7,3′-triglucoside of delphinidin and ferulylcaffeyl 3,7,3′-triglucoside of cyanidin, respectively.

Further evidence for the glycoside structure of cinerarin

The glycoside structure of cinerarin, a dicaffeoyltriglucoside of delphinidin isolated from cineraria, was further studied. Alkaline degradation products of methylated anthocyanin characterized the deacylcinerarin as 3,7,3′-triglucosidyldelphinidin.

Distribution pattern of anthocyanins in the polygonaceae

A survey of anthocyanins in the flowers and other organs of thirty-three species of three genera belonging to the Polygonaceae has been carried out. There are thirteen anthocyans. Cyanidin glycosides, especially the 3-glycoside (chrysanthemin), are present most commonly and peonidin glycosides including the arabinosylglucoside are found with low frequency. The distribution of malvidin 3,5-diglucoside (malvin) is confined to the species belonging to the sectionEchinocaulon of the genusPolygonum. It is noted that cyanidin itself occurs in the stems ofPolygonum perfoliatum andP. senticosum.

A survey of anthocyanins in sprouting leaves of some Japanese angiosperms studies on anthocyanins, LXV

Following some surveys of anthocyanins in the flowers, fruits and autumnal leaves of plants in the flora of Japan (Hayashi and Abe, 1935, 1955, 1956; Ueno, el al., 1969; Shibata, et al., 1967), an attempt has been made to clarify the nature of the red pigments appearing in the sprouting leaves of a variety of plants in early spring. This paper deals with the results of chromatographic analysis made on the sprouting leaves of 46 species belonging to 28 families in Angiospermae. Although most plants examined contained only chrysanthemin (cyanidin 3monoglucoside) in their sproutirtg leaves as in the autumnal reddening of leaves, other anthocyanins have also been found in several species, namely paeonidin glucoside hi Paeonia spp., and delphinidin derivatives in Nandina and Cayratia. Besides, it is noteworthy that the diglycoside type of cyanidin is sometimes found alone or in coulbination with chrysanthemin, e.g., in the genera Zelkova, Cercidiphyllum, Prunus, Punica and Viburnum, as seen from Table 2. Most of the plant materials were collected from March to May in the Senshun-en Garden of Tokyo Kyoiku University and the Botanical Garden of the University of Tokyo. Extracts from the fresh leaves were made with cold 1% MeOH-HC1, and a preliminary purification of anthoeyanins was made by large-scale paper chromatography using BuOH/HC1/H20 (7:2:5, v/v) and then AeOH/HC1/H20 (15:3:82, v/v). After acid hydrolysis of the anthocyanins thus separated, paper chromatography was applied for the identification of individual components, i.e., sugars (BuOH/Pyridine/H20 (6:3:1, v/v)) and organic acids (H~O/HCOOH/HCOONa (200 ml:2 m/:10 g) ). The identification of aglycones and original glycosides was made by the TLC method on a plate of mieroerystalline cellulose (Avieel) by careful comparison of these Rfvalues with those of the authentic samples, as shown in Table 1.

Anthocyanins and their distribution in the genusEpimedium

Anthocyanins contained in plants belonging to the genusEpimedium in Japan are discussed in this study. Two kinds of anthocyanin, delphinidin 3-p-coumaroyl-sophoroside-5-glucoside (cayratinin) and cyanidin 3-p-coumaroylsophoroside, were identified, and the latter is new to the literature. Only cayratinin was found in the colored petals of theEpimedium species, but cayratinin and cyanidin glucoside were contained in the stems, young leaves and autumn leaves of all the species surveyed.

PURIFICATION AND CHARACTERIZATION OF AN S-ADENOSYL-L-METHIONINE:FLAVONOID 3'-O-METHYLTRANSFERASE FROM LEAVES OF TRILLIUM APETALON MAKINO

Abstract In the leaf extract of Trillium apetalon (Liliaceae) distributed in Japan, an enzyme was demonstrated which catalyzes a m ethyl group transfer from S-adenosyl-ʟ-m ethionine (SAM) to the 3′ position of quercetin and its glycosides. The enzyme ( Trillium F3′OMT ) was purified 433-fold with a yield of 0.2% by (NH4)2SO4 precipitation and chromatographies of DEAE - cellulose, SAH-EAH-Sepharose 4B , Sephacryl S-200 and additional chrom atofocusing. Trillium F3′OMT has a pH optimum of 7.0 and a pi of 5.3. The apparent m olecular weight was estimated by Sephacryl S-200 to be about 78 kD a; SD S-PAGE profile showed that the enzyme was a dim er com posed of MW 38 kDa 2 subunits. The enzyme activity was stimulated by EDTA and dithiothreitol (DTT), but strongly inhibited by p-chlorom ercuribenzoate (PCMB) and iodoacetate. The activity was m oderately inhibited by Mg2+ and Zn2+, and strongly inhibited by Co2+, Mn2+ and Hg2+. The apparent Km values for quercetin and SAM were 10 μm and 3.6 μm , respectively. Lower substrate specificity of the glycosides compared with quercetin indicates that methylation precedes glycosylation in flavonoid biosynthesis of T. apetalon

Flavonol Glycosides from Paederia scandens var. mairei

Abstract Four kaempferol glycosides and five quercetin glycosides have been isolated from a methanolic extract of Paederia scandens var. mairei leaves and stems, in which in addition four unknown glycosides of kaempferol and quercetin are present in a trace. Nine flavonol glycosides including a new glycoside quercetin 3-O-rutinoside-7-O-xylosylglucoside (paederinin) were identified by PC, HPLC, UV spectral and NMR studies.