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Ripe Pu-er tea, a special microbial postfermented tea originated from Yunnan Province, China, since ancient times, is made from green Pu-er tea prepared from the leaves of Camellia sinensis var. assamica (Theaceae). Chemical investigation on thearubigin (n-BuOH-soluble) fraction of the commercial ripe Pu-er tea, led to the identification of four new flavan-3-ol derivatives, 8-carboxymethyl-(+)-catechin (1), 8-carboxymethyl-(+)-catechin methyl ester (2), 6-carboxymethyl-(+)-catechin (3), and 6-carboxyl-(-)-gallocatechin (4), together with 18 known compounds, including other three flavan-3-ol derivatives (5-7), 10 flavonoid glycosides (8-17), two hydrolyzable tannins (18 and 19), two quinic acid derivatives (20-21), and a purine alkaloid (22). Flavonoid glycosides 8-11 are reported from tea plants for the first time. The thearubigin fraction of ripe Pu-er tea was qualitatively analyzed by HPLC, and gallic acid was found to be the major component. Compounds 4, 6-17, 21 and 22 were tested for their acute activities on insulin sensitivity in differentiated 3T3-L1 adipocytes, but none of them showed significant bioactivity at a concentration of 10 mu M.

During the process exploring anti-viral compounds from Phyllanthus species, eight new highly oxygenated bisabolane sesquiterpenoid glycoside phyllaemblicins G1–G8 (1–8) were isolated from Phyllanthus emblica, along with three known compounds, phyllaemblicin F (9), phyllaemblic acid (10) and glochicoccin D (11). Phyllaemblicin G2 (2), bearing a tricyclo [3.1.1.1] oxygen bridge ring system, is an unusual sesquiterpenoid glycoside, while phyllaemblicins G6–G8 (6–8) are dimeric sesquiterpenoid glycosides with two norbisabolane units connecting through a disaccharide. All the structures were elucidated by the extensive analysis of HRMS and NMR data. The relative configuration of phyllaemblicin G2 was constructed based on heteronuclear coupling constants measurement, and the absolute configurations for all new compounds were established by calculated electronic circular dichroism (ECD) using time dependent density functional theory. The sesquiterpenoid glycoside dimers 6–9 displayed potential anti-hepatitis B virus (HBV) activities, especially for the new compound 6 with IC50 of 8.53 ± 0.97 and 5.68 ± 1.75 μM towards the HBV surface antigen (HBsAg) and HBV excreted antigen (HBeAg) secretion, respectively.

Pu-er ripe tea is a special microbial post-fermented tea made from Pu-er raw tea, a kind of green tea produced from the leaves of Camellia sinensis var. assamica. It is one of the most consumed teas in the past two decades in China, due to its special flavor, taste, and beneficial effects. This work aimed to obtain diverse catechin structures from Pu-er ripe tea, which led to the isolation of four new phenylpropanoid-substituted flavan-3-ols, puerins C-F (1-4), together with four known flavan-3-ols, (+)-catechin (5), (-)-epicatechin (6), (±)-gallocatechin (7), and (-)-epigallocatechin (8). Their structures were elucidated on the basis of detailed spectroscopic analysis, including 1D and 2D NMR, mass and CD spectra. Compounds 1-4, which could be formed in the post-fermentative process of Pu-er tea, were isolated for the first time from tea and Theaceae plant.

NSFC [21002105]; 973 Program of Ministry of Science and Technology of P. R. China [2011CB915503]; Fourteenth Candidates of the Young Academic Leaders of Yunnan Province [2011CI044]; West Light Foundation of the Chinese Academy of Sciences; Korean Chemical Society

To investigate the clinical significance of transforming growth factor-beta 1 (TGF-β1) in children with primary IgA nephropathy (IgAN).Thirty children who were diagnosed with primary IgAN by renal biopsy between May 2008 and October 2012 were included in the study. Thirty healthy children were used as the control group. Urinary and blood TGF-β1 levels were measured using enzyme-linked immunosorbent assay, and the protein expression of TGF-β1 in the renal tissue was measured by immunohistochemistry. The correlation between TGF-β1 levels in blood, urine, and renal tissue and their relationship with clinical indices were analyzed.Children with primary IgAN had significantly higher urinary and blood TGF-β1 levels than the control group (P0.01). Urinary TGF-β1 level was positively correlated with the pathological grade of renal tissue (r=0.557, P=0.001), and a significant positive correlation was also found between the TGF-β1 expression in the renal tissue and the pathological grade of renal tissue (r=0.682, P0.01). There was no correlation between TGF-β1 levels in blood and renal tissue (r=0.038, P=0.844).Urinary TGF-β1 level is significantly positively correlated with the pathological severity of disease in children with primary IgAN. Clinical measurement of urinary TGF-β1 may be of great practical value in predicting the progression and prognosis of chronic nephropathy.

Nineteen new highly oxygenated norbisabolane sesquiterpenoids, phyllanthacidoid acid methyl ester (1), and C-T (4-21), were isolated from Phyllanthus acidus Skeels, together with two known ones, phyllanthusols A (2) and B (3), whose sugar moiety was revised as glucosamine-N-acetate, rather than the previously assigned mannosamine-N-acetate. Compounds 2 and 3 were renamed respectively as phyllanthacidoids A (2) and B (3) to avoid confusion. All of the isolates except for 1 are glycosides, whose saccharide moieties possess a pentaoxy cyclohexane (scyllo quercitol) connecting with glucosamine-N-acetate or glucosyl moieties, which are first examples in natural products. Phyllanthacidoids N-R (15-19) with 8R configurations and/or 5,8-diketal skeleton, are unprecedented structures among norbisabolane sesquiterpenoids. Phyllanthacidoids S (20) and T (21) have the unusual tricyclo [3.1.1.1] oxygen bridge skeleton formed by a diketal system, of which the relative configurations of the aliphatic chain were assigned on the basis of heteronuclear coupling constants. The absolute configurations of compounds (1-21) were established by means of calculated electronic circular dichroism (ECD) and coupling constants. Compounds 1-5, 7-9, 10, and 14 displayed potential anti-hepatitis B virus (HBV) activities, with IC50 values of 0.8-36 mu M against HBV surface antigen (HBsAg) and HBV excreted antigen (HBeAg), and the results indicated that the S-ketal group and sugar moieties had contributions to the selectivity of HBsAg and HBeAg.

Two new highly oxygenated limonoids, flexuosoids A (1) and B (2), and three new arylnaphthalene lignan glycosides, phyllanthusmins D-F (3-5), were isolated from the roots of Phyllanthus flexuosus, in addition to three known lignans, phyllanthusmin C, arabelline, and (+)-diasyringaresinol. Their structures were elucidated on the basis of detailed spectroscopic analysis and chemical methods. Compounds 1 and 2, two new decaoxygenated limonoids with a C-19/29 lactol bridge and heptaoxygenated substituents at C-1, C-2, C-3, C-7, C-11, C-17, and C-30, represent the second example of limonoids in the Euphorbiaceae family. Most of the isolates were tested for their antifeedant, anti-herpes simplex virus 1, and cytotoxic activities. The new limonoids 1 and 2 showed promising antifeedant activity against the beet army worm (Spodoptera exigua) with EC50 values of 25.1 and 17.3 μg/cm(2), respectively. In addition, both of them displayed moderate cytotoxicity against the ECA109 human esophagus cancer cell line, along with the known lignan glycoside, phyllanthusmin C, with the IC50 values of 11.5 (1), 8.5 (2), and 7.8 (phyllanthusmin C) μM, respectively.Two new highly oxygenated limonoids, flexuosoids A (1) and B (2), and three new arylnaphthalene lignan glycosides, phyllanthusmins D-F (3-5), were isolated from the roots of Phyllanthus flexuosus, along with three known lignans. Flexuosoids A (1) and B (2) showed promising antifeedant activity against the beet army worm (Spodoptera exigua) with EC50 values of 25.1 and 17.3 μg/cm(2), respectively. In addition, both of them and the known lignan glycoside, phyllanthusmin C, displayed moderate cytotoxicity against the ECA109 human esophagus cancer cell line, with the IC50 values of 11.5, 8.5, and 7.8 μM, respectively.

6′-O-Caffeoylarbutin, an arbutin derivative, is a naturally occurring glucoside of hydroquinone from Vaccinium dunalianum. On anti-melanogenic effect assay, 6′-O-caffeoylarbutin expressed a stronger anti-melanin activity in a dose-dependent manner with about a two-fold more than that of arbutin, but with less toxicity about a two-fold lower than that of arbutin. In addition, melanin synthesis could be fully recovered after the removal of 6′-O-caffeoylarbutin. The result suggested that 6′-O-caffeoylarbutin could be a candidate natural product to serve as a skin-whitening ingredient with the merits of potent melanin inhibition, less toxicity and reversible melanin synthesis after stopping use.

Chemical investigation of the whole plants of Phyllanthus cochinchinensis (Euphorbiaceae) led to the isolation of three new phenolic glycosides, phyllanthuosides A-C, together with 12 known compounds. Their structures were established on the basis of extensive spectroscopic analysis and chemical methods. Among them, phyllanthuosides A and B are two of the rare phenolic glycosides, featuring with a C6-C3-C6 skeleton. The absolute configurations of phyllanthuosides A and B were established by calculated electric circular dichroism (ECD) using time dependent density functional theory (TDDFT). The isolates were also tested for their cytotoxicity and antimicrobial activity.

A novel C-C-coupled dimer derivative of bergenin was produced by the biotransformation of cultured mycelia of white rot fungus Pleurotus ostreatus. Its structure was elucidated by detailed spectroscopic analysis.

Three new diterpenoids - phyllanflexoids A-C (I), (II), and (III) - are isolated from roots of Phyllanthus flexuosus.

Two new oleanane-type triterpenoid saponins (1 and 2) were isolated from the methanolyzed total saponins of the seeds of Momordica cochinchinensis (Lour.) Spreng, together with 16 known compounds (3—18). Their structures were elucidated on the basis of detailed spectroscopic, including ID and 2D NMR, mass spectrometric, methanolysis and LC-MS analysis. All the isolates were tested for their cytotoxic activities against five human cancer cell lines (HL-60, SMMC-7721, PANC-1, A-549, and SW-480) and the glucose uptake activity. The known compound 6 exhibited toxic effects against HL-60 with an IC50 value of 18.1 μM, while 10 showed cytotoxicity against SMMC-7721 and A-549 cell lines, with IC50 values of 34.4 and 32.8 μM, respectively. In addition, the new compound 2 showed glucose uptake activity with a glucose consumption value of 0.29 μM at 10 μM concentration.

A micromechanically based continuum model is developed to analyze the enhancement of plastic properties of particulate-reinforced metal-matrix composites over matrix materials. The composite is idealized as uniformly distributed periodic arrays of unit cells. Each unit cell consists of a rigid inclusion surrounded by a plastically deforming material. An energy method is adopted to obtain the overall constitutive relation for the composite on the basis of the local nonuniform deformation fields. Effects of particle volume fractions and shapes (e.g. whiskers, discs, etc.) as well as the matrix properties on the flow properties of the composite are obtained. The results are in good agreement with experimental observations and finite element analyses found in the literature. An explicit expression is also proposed, providing a means for evaluating various factors affecting the strength of composites.

Camellia taliensis (W. W. Smith) Melchior, belonging to the genus Camellia sect. Thea (Theaceae), is an endemic species distributed from the west and southwest of Yunnan province, China, to the north of Myanmar. Known as a wild tea tree, its leaves have been used commonly for producing tea beverages by the local people of its growing area. One new flavan-3-ol dimer, talienbisflavan A (1), was isolated from green tea prepared from the leaves of C. taliensis collected from the east side of the Ai-Lao mountains, Yuanjiang county of Yunnan province, China. In addition, five hydrolyzable tannins (2-6), five flavonols and flavonol glycosides (9-13), three flavan-3-ols (14-16), nine simple phenolic compounds and glycosides (7, 8, and 17-23), and caffeine (24) were identified. Their structures were determined by detailed spectroscopic analysis. All of the isolated phenolic compounds were tested for their antioxidant activities by DPPH and ABTS(+) radical scavenging assays. The contents of its main chemical compositions were also compared with those collected from the Lincang area of Yunnan province by high-performance liquid chromatography analysis.

This paper presents a reasoning algorithm based on interaction with fuzzy rule matrix transformation, and applies it to completing the patterns. Then the new full patterns will be used in training and synthetic judgment. The investigation shows that the method is effective and may be widely used in Reasoning with Incomplete Knowledge.

A hairy root strain has been established from the root explants of P. japonicus var. major by using a wild strain pRi 15834 of Agrobacterium rhizogenes. Experimental data on the time-course of hairy root growth and saponin formation in suspension culture indicate that both the dry weight of the hairy roots and total saponin yield reached their maximum values on the 30th day. It means that saponin formation proceeds almost in parallel with hairy root growth. The oligosaccharins DC-DP7, DC-DP8 DC-DP9 from Dendrobium candidum, and PP-DP6, PP-DP7, PP-DP8 from Paris polyphylla var. yunnanensis all affected the hairy root growth, especially obviously stimulated saponin formation of the hairy roots.

Background Panax notoginseng is an important Chinese medicinal plant. Dammarene-type triterpenoid saponins are main pharmacologically effective compounds in P. notoginseng. This study aims to investigate the formation and accumulation of saponins in P. notoginseng roots during germination and juvenile stage. Methods P. notoginseng seeds were collected and stored in wet sand. After germination, the seedlings were transplanted into a soil nursery bed and cultivated for one year. During this period, samples were collected every month and the concentrations of ginsengnosides Rg1, Re, Rb1, Rd and notoginsengnoside R1 were determined by HPLC. Results There was little saponin in the P. notoginseng seed. The chemical composition of seed was different from that of root. After germination, Rb1, Rg1, Re, Rd and R1 appeared successively in the seedling root. And in the five-month-old root, all these five main saponins came into existence. The accumulation of saponins in P. notoginseng root was affected by seasons. Conclusion The accumulation of saponins showed a time-dependent increase after germination of P. notoginseng.

“Long-Dan” is an important traditional Chinese medicinal (TCM) herb used widely for the treatment of inflammation, hepatitis, rheumatism, cholecystitis, and tuberculosis. In the Chinese Pharmacopoeia, the roots and rhizomes of four species from the genus Gentiana (Gentianaceae) are recorded as the original materials of “Long-Dan”, called Gentianae Radix et Rhizoma. The species included G. manshurica, G. scabra, G. triflora and G. rigescens, which are distributed in different areas of China. Though iridoid and secoiridoid glucosides were reported as the main constituents in “Long-Dan”, these four different species also resulted in different minor components, which may related to their pharmacological activities. Herein, we summarized the herbal textual study, distribution, chemical constituents, biological investigation and quality control of the recorded “Long-Dan” origins in Chinese Pharmacopoeia during the period 1960 to 2011.