Medicinal Flowers. XXXV. Nor-oleanane-type and acylated oleanane-type triterpene saponins from the flower buds of Chinese <i>Camellia japonica</i> and their inhibitory effects on melanogenesis¹⁾

Abstract

The methanolic extract and its 1-butanol-soluble fraction from the flower buds of Camellia japonica, cultivated in Yunnan Province, China, showed inhibitory effects on melanogenesis in theophylline-stimulated B16 melanoma 4A5 cells. From the 1-butanol-soluble fraction, a new 28-nor-oleanane-type and three new oleanane-type triterpene saponins, sanchakasaponins A-D, were isolated together with four known triterpene saponins. Their chemical structures were elucidated on the basis of chemical and physicochemical evidence. The inhibitory effects on melanogenesis in theophylline-stimulated B16 melanoma 4A5 cells and structure-activity relationships of the saponins were investigated.Key words Camellia japonica; sanchakasaponin; medicinal flower; triterpene oligoglycoside; melanogenesis inhibitorThe Theaceae plant, Camellia japonica L., has been widely cultivated as an ornamental plant in Japan, China, and Taiwan. The flower buds of C. japonica have been used for the treatment of blood stagnation, vomiting of blood and bleeding due to internal and external injury, and also as an anti-inflammatory, tonic, and stomatic in Japanese folk medicine and Chinese traditional medicine. As chemical constituents of this plant, saponins in the fruit and seeds, [2][3][4][5] flavonol glycosides in the leaves, 6) and triterpenes, 7) several hydrolyzable tannins, 8) acylated anthocyanins, 9) and purin alkaloids 10) in the flower have been reported. In the course of our studies on bioactive constituents of the flower buds of Camellia species, we have isolated triterpene saponins from C. sinensis L. (chakasaponins I-VI, floratheasaponins A-J), [11][12][13][14][15][16] C. oleifera ABEL (yuchasaponins A-D), 17) and C. sasanqua THUNB. (sasanquasaponins I-V). 18)Furthermore, antiallergic, antidiabetic, antiobestic, and gastroprotective effects of these saponins have also been reported. Additionally, we have reported the isolation of triterpene saponins, camelliosides A-D, with gastroprotective and platelet-aggregating effects from the flower buds of C. japonica cultivated in Japan. 19,20) As a continuation of our studies on bioactive constituents from the flower buds of C. japonica, we found the methanolic extract and its 1-butanol-soluble fraction of C. japonica cultivated in Yunnan Province, China to have significant inhibitory effects on melanogenesis in theophylline-stimulated B16 melanoma 4A5 cells. From the 1-butanol-soluble fraction, we have isolated a new 28-nor-oleanane-type triterpene saponin, sanchakasaponin A (1), and three new acylated oleanane-type triterpene saponins, sanchakasaponins B (2), C (3), and D (4), together with four known triterpene saponins (Fig. 1). In this paper, we describe the isolation and structural elucidation, inhibitory effects on melanogenesis in theophylline-stimulated B16 melanoma 4A5 cells, and structure-activity relationships of the new triterpene saponins.The methanolic extract (10.0% from the dried flower buds of C. japonica cultivated in Yunnan Province, China) with the inhibitory effect on melano...

Medicinal Flowers. XXXX.¹⁾ Structures of Dihydroisocoumarin Glycosides and Inhibitory Effects on Aldose Reducatase from the Flowers of <i>Hydrangea macrophylla</i> var. <i>thunbergii</i>

“…[2][3][4][5][6] However, a full chemical analysis of the flowers from this plant has not yet been performed. In the course of our chemical and pharmacological studies on Hydrangea plants [2][3][4][5][6][7][8] and medicinal flowers, [9][10][11][12][13][14] we recently reported the isolation and structure elucidation of secoiridoid glycosides named hydrangeamines A and B with a pyridine ring from the flowers of H. macrophylla var. thunbergii cultivated in Nagano prefecture, Japan.…”

Separation of nine novel triterpene saponins from Camellia japonica seeds using high‐performance countercurrent chromatography and reversed‐phase high‐performance liquid chromatography

“…Camellia japonica L. (Theaceae) is an evergreen shrub and one of the best‐known species of the genus Camellia along with tea tree ( C. sinensis ). In Asian countries, including Korea, China, and Japan, C. japonica is cultivated as a popular ornamental tree and its seeds are a good source of cooking oil, and used in cosmetics and traditional medicine …”

“…Several studies have been performed to identify the flavonoids in the flowers and leaves of C. japonica, and extensive phytochemical works have revealed that oleanane‐type saponins are the characteristic compounds of the seeds of C. japonica and C. sinensis. Although saponins are regarded as the main components in C. japonica , their high‐performance liquid chromatography (HPLC) analysis has rarely been reported. In general, saponins are detected by HPLC using short‐wavelength ultraviolet (UV) detection or evaporative light scattering detection (ELSD).…”

Detection and Identification of an Elm Yellows Group Phytoplasma Associated with Camellia in China

“…The flower buds of C. japonica have been used as an anti‐inflammatory in Chinese traditional medicine, and also have therapeutic efficacy for hemoptysis, blood stagnation and bleeding due to internal and external injury (Fujimoto et al. ; Kim et al. ).…”

“…It can be use as the tea, seed oil and it also has some medicinal value. The flower buds of C. japonica have been used as an antiinflammatory in Chinese traditional medicine, and also have therapeutic efficacy for hemoptysis, blood stagnation and bleeding due to internal and external injury (Fujimoto et al 2012;Kim et al 2012). In 2012, camellia plants with symptoms of yellowing, which was similar to the symptoms of tree peony yellows disease (Gao et al 2013), were observed in Tai'an in Shandong province, China.…”