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Camellia taliensis (W. W. Smith) Melchior, belonging to the genus Camellia sect. Thea., is mainly distributed from northern Myanmar to western and southwestern Yunnan province of China, and its leaves have been used to make various teas by the locals of its growing regions. The chemical constituents of C. taliensis are significantly related to those of cultivated tea plants, C. sinensis and C. sinensis var. assamica. The HPLC-ESI-MS analysis of black tea prepared from the leaves of C. taliensis showed a rich existence of polyphenols. Further comprehensive chemical study led to the separation and recognition of 32 compounds (1–32), including one new hydrolyzable tannin, 1-O-galloyl-4,6-tetrahydroxydibenzofurandicarboxyl-β-D-glucopyranose (1), and one new natural product (24). The known compounds referred to seven hydrolyzable tannins (2–8), 10 flavonols and glycosides (9–18), and 14 simple phenolics (19–32). Their structures were elucidated by comprehensive spectroscopic analyses. Among them, 20 compounds (2, 3, 6, 7, 8, 15, 17, 18, 20–22, 24–32) were isolated from black tea for the first time. Most isolates displayed obvious antioxidant activities on DPPH and ABTS+ assays, and the hydrolyzable tannins 1, 3–5, 7, and 8 exhibited stronger inhibitory activities on α-glycosidase than quercetin and acarbose (IC50 = 5.75 and 223.30 μM, respectively), with IC50 values ranging from 0.67 to 2.01 μM. [ABSTRACT FROM AUTHOR]

Eleven flavonoids including one new flavonol glycoside, quercetin-3-O-(2-α-L-rhamnopyranosyl)-β-D-glucuronopyranosyl methyl ester (1), were isolated for the first time from the fruits of Phyllanthus acidus (L.) Skeels (Phyllanthaceae). Their structures were determined by extensive spectroscopic data. The known flavonoids, quercetin-3-O-β-D-glucuronide methyl ester (3), quercetin-3-O-(2''-α-L-rhamnopyranosyl-6''-O-α-L-rhamno pyranosyl)-β-D-glucopyranoside (5), myricetin (9), and 6-methoxy-naringenin (11) were isolated for the first time from the genus Phyllanthus. Flavonoids 4, 6 and 9 (IC50 = 6.01, 6.32, and 7.84 μM, respectively) showed stronger α-glucosidase inhibitory activities than the positive control, acarbose (IC50 = 306.45 μM). The fruits of P. acidus might be further developed as an anti-diabetic food supplement. [ABSTRACT FROM AUTHOR]

A new seco-anthraquinone, crispuside A (1), and three new 3,4-dihydronaphthalen-1(2H)-ones, napthalenones A-C (2–4), were isolated from the roots of Rumex crispus L., along with 10 known anthraquinones (6–14) and naphthalenone (5). Their structures were fully determined by extensive spectroscopic analyses, including ECD, and X-ray crystallography in case of compound 5, whose absolute configuration was determined for the first time. The isolates 1, 6–14 were evaluated for their anti-inflammatory and anti-fungal activity against three skin fungi, e.g., Epidermophyton floccosum, Trichophyton rubrum, and Microsporum gypseum. Most of the isolates showed weak anti-fungal and anti-inflammatory activity. Only compound 9 exhibited obvious anti-fungal activity against E. floccosum (MIC50 = 2.467 ± 0.03 μM) and M. gypseum (MIC50 = 4.673 ± 0.077 μM), while the MIC50 values of the positive control terbinafine were 1.287 ± 0.012 and 0.077 ± 0.00258 μM, respectively. The results indicated that simple emodin type anthraquinone is more potential against skin fungi than its oxyglucosyl, C-glucosyl and glycosylated seco analogues. [ABSTRACT FROM AUTHOR]

Rumex L., a genus in Polygonaceae family with about 200 species, is growing widely around the world. Some Rumex species, called "sorrel" or "dock", have been used as food application and treatment of skin diseases and hemostasis after trauma by the local people of its growing areas for centuries. To date, 29 Rumex species have been studied to contain about 268 substances, including anthraquinones, flavonoids, naphthalenes, stilbenes, diterpene alkaloids, terpenes, lignans, and tannins. Crude extract of Rumex spp. and the pure isolates displayed various bioactivities, such as antibacterial, anti-inflammatory, antitumor, antioxidant, cardiovascular protection and antiaging activities. Rumex species have important potential to become a clinical medicinal source in future. This review covers research articles from 1900 to 2022, fetched from SciFinder, Web of Science, ResearchGate, CNKI and Google Scholar, using “Rumex” as a search term ("all fields") with no specific time frame set for the search. Thirty-five Rumex species were selected and summarized on their geographical distribution, edible parts, traditional uses, chemical research and pharmacological properties. [ABSTRACT FROM AUTHOR]

The separable nonlinear least-squares (SNLLS) problems considered in this article frequently appear in a wide range of research fields, such as machine learning, computer vision, system identification, and signal processing. The variable projection algorithm proposed by Golub and Pereyra, which reduces the dimension of the parameters by projecting the linear parameters out of the problem, is quite valuable in solving SNLLS problems. Previous implementations of the variable projection algorithm are based on matrix factorization. In this article, we propose an iterative implementation of the variable projection algorithm. Compared with previous implementations based on matrix decomposition, the proposed method can effectively avoid suffering from large condition number of the matrix or even matrix decomposition failure when dealing with ill-posed SNLLS problems. Numerical experiments on real-world data and synthetic data show the efficiency and robustness of the proposed iterative variable projection algorithm. [ABSTRACT FROM AUTHOR]

Phyllaciduloids E (1) and F (2), two new cleistanthane diterpenoids, were isolated from the leaves of Phyllanthus acidus (L.) Skeels (Phyllanthaceae). Their planar structures were established by spectroscopic analysis and comparison with literature values. The relative configurations of phyllaciduloids E and F were confirmed by DFT-NMR chemical shift calculations and subsequent CP3 probability methods. Phyllaciduloids E and F were evaluated for their cytotoxicity. However, no significant activities were detected at concentrations up to 40 μM. [ABSTRACT FROM AUTHOR]

The broad learning system (BLS) is an emerging flat network, which has demonstrated its outstanding performance in classification and regression problems. The regularization plays an important role in the performance of the BLS. In real applications, since the BLS network is usually expanded dynamically, a predetermined regularization parameter may reduce the performance of the network. Using a fixed regularization in some cases, the classification accuracy of the BLS decreases dramatically when we expand the network. To alleviate this problem, we propose a method that automatically finds appropriate regularization parameters for different datasets, which is based on the weighted generalized cross-validation (WGCV). The experimental results indicate that the WGCV method improves the performance of the BLS, and alleviates the accuracy decrease of the incremental learning algorithm. [ABSTRACT FROM AUTHOR]

A novel highly oxygenated norbisabolane sesquiterpene, namely phyllanthacidoid U (1), along with nine known sesquiterpenes (2–10) was isolated from the roots and stems of Phyllanthus acidus (L.) Skeels (Phyllanthaceae), collected from Xishuangbanna, Yunnan province, China. Their structures were elucidated by means of extensive spectroscopic analysis and by comparison of their data with reported values in literatures. Instead of the C-13 ester O-glycosyl found mostly in the titled plant growing in Thailand, compound 1 possessed a rare N-β-glucosamine-2-N-acetate moiety linked directly to the carbonyl at C-13 through an amido bond. Moreover, the acyl group at C-10 in 1 was (Z)-2-(2-hydroxyethyl)-pent-2-enedioyl group, instead of benzoic or p-hydroxybenzoic moieties found commonly in the reported norbisabolane sesquiterpenes. The known sesquiterpene 5 displayed stronger anti hepatitis B virus (HBV) activity with IC50 values of 1.69 ± 0.22 and 2.79 ± 0.69 μM towards HBV surface antigen (HBsAg) and HBV excreted antigen (HBeAg) secretion, respectively. [ABSTRACT FROM AUTHOR]

The extensive chemical investigation on the branches and leaves of Terminalia chebula var. tomentella (Combretaceae) led to the isolation of two new lignan glucosides with a furofuran skeleton, termitomenins F (1) and G (2). In addition, 19 known compounds including five lignan glucosides (3–7), six hydrolyzable tannins (8–13) and eight simple phenolics (14–21) were also identified. Their structures were determined by comprehensive spectroscopic analyses. It is noted that 8 and 9 were C-glycosidic hydrolyzable tannins with one hexahydroxydiphenoyl and one gallagyl group linked to an open-chain glucosyl C-1/O-2/O-3 and O-4/O-6, respectively, which were rarely found in plants. Nine known compounds, 6–9, 13, and 18–21, were procured from the titled plant for the first time, while 3–5, 10–12 and 14–17 were also found in the fruits. Notably, the known hydrolyzable tannins 8–13 exhibited stronger α-glucosidase inhibitory activities with IC50 values ranging from 0.10 to 3.12 μM, than the positive control, quercetin (IC50 = 9.38 ± 0.33 μM). [ABSTRACT FROM AUTHOR]

Background: Management errors during pre-hospital care, triage process and resuscitation have been widely reported as the major source of preventable and potentially preventable deaths in multiple trauma patients. Common tools for defining whether it is a preventable, potentially preventable or non-preventable death include the Advanced Trauma Life Support (ATLS®) clinical guideline, the Injury Severity Score (ISS) and the Trauma and Injury Severity Score (TRISS). Therefore, these surrogated scores were utilized in reviewing the study's trauma services. Methods: Trauma data were prospectively collected and retrospectively reviewed from January 1, 2018, to December 31, 2018. All cases of trauma death were discussed and audited by the Hospital Trauma Committee on a regular basis. Standardized form was used to document the patient's management flow and details in every case during the meeting, and the final verdict (whether death was preventable or not) was agreed and signed by every member of the team. The reasons for the death of the patients were further classified into severe injuries, inappropriate/delayed examination, inappropriate/delayed treatment, wrong decision, insufficient supervision/guidance or lack of appropriate guidance. Results: A total of 1913 trauma patients were admitted during the study period, 82 of whom were identified as major trauma (either ISS > 15 or trauma team was activated). Among the 82 patients with major trauma, eight were trauma-related deaths, one of which was considered a preventable death and the other 7 were considered unpreventable. The decision from the hospital's performance improvement and patient safety program indicates that for every trauma patient, basic life support principles must be followed in the course of primary investigations for bedside trauma series X-ray (chest and pelvis) and FAST scan in the resuscitation room by a person who meets the criteria for trauma team activation recommended by ATLS®. Conclusion: Mechanisms to rectify errors in the management of multiple trauma patients are essential for improving the quality of trauma care. Regular auditing in the trauma service is one of the most important parts of performance improvement and patient safety program, and it should be well established by every major trauma center in Mainland China. It can enhance the trauma management processes, decision-making skills and practical skills, thereby continuously improving quality and reducing mortality of this group of patients. [ABSTRACT FROM AUTHOR]

The fresh leaves of Metapanax delavayi (Araliaceae) have been used as a common wild vegetable for salad and soup, and also herbal tea by the local people living in its growing areas of Yunnan province, China. Detailed chemical investigation led to the identification of a new triterpenoid saponin, 3-O-α-L-arabinopyranosyl-28-O-β-D-glucopyranosyl-(1→6)-O-β-D-glucopyranosyl-3β-hydroxyolean-12-ene-28,29-dioic acid (1) from the fresh leaves, together with 11 known compounds, including six triterpenoid saponins (2–7), two caffeoylquinic acid derivatives (8–9), and three flavonoid glycosides (10–12). Their structures were determined on the basis of spectroscopic analysis and acidic hydrolysis. Compounds 3–5 and 8–12 were isolated from M. delavayi for the first time. Moreover, the known saponins 3-O-β-D-xylopyranosyl-3β-hydroxyolean-12-ene-28,29-dioic acid (3) and yiyeliangwanoside IV (5) exhibited protective effects on HepG2 cells damaged by the alcohol intakes, at a concentration of 1.0 µg/mL. The results indicated M. delavayi is an ideal dietary vegetable and herbal tea with potential hepatoprotective activity. [ABSTRACT FROM AUTHOR]

Dasiphora fruticosa L. (Rosaceae), also known as Potentilla fruticosa L. (syn.), is a hardy deciduous shrub widely distributed in the north temperate regions of the world. Three methylene bisflavan-3-ols (1-3), together with a procyanidin dimer, (-)-afzelechin-(4α→8)-(-)-afzelechin (4) were isolated for the first time from the branches and leaves of the titled plant, in addition to 11 known compounds (5-15). Their structures were elucidated by means of extensive spectroscopic analysis and by comparison with data reported in the literatures. Methylene 6,8-bis(7-O-glucosyl) catechin (1) was determined to be a new dimeric flavan-3-ol glycoside through a methylene linkage between C-8 and C-8 of two units. At a concentration of 128 μg/mL, the known compounds 9 – 13 exhibited antibacterial activities on Escherichia coli, Staphylococcus aureus subsp. aureus, Salmonella enterica subsp. enterica, and Pseudomonas aeruginosa. Compound 12 also showed certain glucose uptake stimulating activity. [ABSTRACT FROM AUTHOR]

Objective To investigate the expression heterogeneity of transforming growth factor-β-induced protein (TGFBI) in glioblastoma (GBM) multiform and the mechanism of its promotion on malignancy of glioma stem cells (GSCs) in vitro. Methods Using The Cancer Genome Atlas (TCGA), Chinese Glioma Genome Atlas (CGGA), REMBRANDT and Oncomine database to analyse the potential associations between grades, subtypes, overall survival (OS) of GBM and the expression level of TGFBI and the correlation between TGFBI and tumor-associated macrophages (TAMs) marker CD11b and CD163. Treating human monocytes cell line U937 with sequential peripheral blood mononuclear cells and IL-4 to get Primed- and M2-TAMs, quantitative real-time polymerase chain reaction (qRT-PCR) were used to detect the expression level of markers for M1 -, M2 - TAMs and TGFBI. Performing immunofluorescent and immunohistochemical stain to reveal the distribution of TGFBI, M2-TAMs and GSCs in specimen of GBM patients, adding rhTGFBI to the culture medium to see its impacts on the sphere formation and invasion capacity of NCH-421K. Results According to the RNA-seq and microarray data of GBM patients in each database, expression level of TGFBI positively correlated to GBM grades and negatively to OS, Furthermore, expression level of TGFBI were strongly correlate with either pan TAMs marker CD11b or M2-TAMs marker CD163, and as the induction of U937-derived M2-TAMs, the expression level of M2-TAMs marker and TGFBI increased accompanied by decreasingly M1-TAMs marker. Also, we found an obvious co-location between TGFBI and CD163, SOX2 in frozen and paraffin sections of GBM specimens. Lastly, we demonstrate that rhTGF86BI could enhance the sphere formation and invasion capacity of NCH-421K in vitro. Conclusions M2-TAMs secrete TGFBI to promote the sphere formation and invasion capacity of GSCs in GBM. [ABSTRACT FROM AUTHOR]

Terminalia Linn, a genus of mostly medium or large trees in the family Combretaceae with about 250 species in the world, is distributed mainly in southern Asia, Himalayas, Madagascar, Australia, and the tropical and subtropical regions of Africa. Many species are used widely in many traditional medicinal systems, e.g., traditional Chinese medicine, Tibetan medicine, and Indian Ayurvedic medicine practices. So far, about 39 species have been phytochemically studied, which led to the identification of 368 compounds, including terpenoids, tannins, flavonoids, phenylpropanoids, simple phenolics and so on. Some of the isolates showed various bioactivities, in vitro or in vivo, such as antitumor, anti HIV-1, antifungal, antimicrobial, antimalarial, antioxidant, diarrhea and analgesic. This review covers research articles from 1934 to 2018, retrieved from SciFinder, Wikipedia, Google Scholar, Chinese Knowledge Network and Baidu Scholar by using "Terminalia" as the search term ("all fields") with no specific time frame setting for the search. Thirty-nine important medicinal and edible Terminalia species were selected and summarized on their geographical distribution, traditional uses, phytochemistry and related pharmacological activities. [ABSTRACT FROM AUTHOR]

The sequential extraction method was used to determine the fraction of arsenic (As) in different-sized particulate matters (PMs) (i.e., PM2.5, PM10, and total suspended particles (TSP)). Samples were collected from Baoding, a typical medium-sized city with the serious haze pollution in China. The bioavailabilities of As in the samples were estimated based on the fraction results. A large percentage of fine particles were detected in TSP, with the average PM2.5/PM10 and PM10/TSP ratios all above 0.69. The total concentrations of As in PM2.5, PM10, and TSP samples were in the range of 4.5–296.4, 14.1–708.0, and 32.8–798.0 ng m−3, respectively. The mass percentages of As in PM2.5, PM2.5–10, and PM10–100 were calculated; the results indicated that As tended to concentrate in fine particles. PM-bound As mainly presented in the nonspecifically sorbed fraction (F1) during all of the sampling periods. The percentages of F1-As and bioavailability of As were higher in PM2.5, followed by PM10 and TSP. By contrast, the residual fraction (F5-As) contents declined in the order of TSP > PM10 > PM2.5. Significant differences in the speciation and bioavailability of As in different-sized PMs were found, and the influence of particle size on the speciation and bioavailability of As in PMs was verified. Fine particles adsorbed more As with higher bioavailability, and potentially led to more serious adverse effects on human health than the larger ones. [ABSTRACT FROM AUTHOR]

Four new protopanaxatriol-type triterpenes (1–2) and glucosides (3–4), were isolated from the rot roots of Panax notoginseng (Burk.) Chen, along with four known ones (5–8). Their structures were elucidated on the basis of extensive spectroscopic analysis (HRESIMS, NMR, UV, IR, and OR) and acidic hydrolysis. The possible transformation pathway of these compounds were also speculated from ginsenoside Rg1. Compound 1, with a unique α,β-unsaturated ketene in its side chain, showed significant inhibitory effects against NO production on Murine macrophage cells (IC50 = 4.12 ± 0.20 μM) and comparable cytotoxicities against five human cancer cell lines (myeloid leukemia HL-60, lung cancer A-549 cells, hepatocellular carcinoma SMMC7721, breast cancer MCF-7, and colon cancer SW480) to positive control, cisplatin (DDP). [ABSTRACT FROM AUTHOR]

Two new sphingofungins G (1) and H (2) with a five-membered lactone ring were identified from the solid-state fermentation of Aspergillus penicilliodes Speg., a dominant microorganism isolated previously from the post-fermentation of ripe Pu-er tea, together with six known metabolites. Their structures were elucidated by extensive spectroscopic methods. All of them were isolated from the mycelia culture of A. penicilliodes for the first time. The known compound, trypacidin, exhibited potent cytotoxities against five human cancer cell lines, e.g. myeloid leukemia HL-60, lung cancer A-549, hepatocellular carcinoma SMMC7721, breast cancer MCF-7, and colon cancer SW480, with IC50 values of 0.55, 11.45, 10.95, 3.58, and 3.49 μM, resp., while cisplatin as the positive control, with IC50 values of 8.63, 24.15, 21.99, 27.29, and 23.61 μM, resp. [ABSTRACT FROM AUTHOR]

Abstract: Panax notoginseng (Araliaceae) is a famous traditional Chinese medicine mainly cultivated in Yunnan and Guangxi provinces of China. Two new alkaloids, rigidiusculamide E (1) and [-(α-oxyisohexanoyl-N-methyl-leucyl)2-] (2), together with two known ones, (−)-oxysporidinone (3) and (−)-4,6′-anhydrooxysporidinone (4) were isolated from the mycelia culture of Fusarium tricinctum SYPF 7082, an endophytic fungus obtained from the healthy root of P. notoginseng. Their structures were determined on the basis of extensive spectroscopic analyses. Compounds 1-4 were tested for their inhibitory effects against NO production on Murine macrophage cell line, and the new compound 2 showed significant inhibitory activity on NO production with the IC50 value of 18.10 ± 0.16 μM.Graphical Abstract: [ABSTRACT FROM AUTHOR]

Abstract: Panax, a genus of the Araliaceae family, is an important herbal group in traditional Chinese medicine (TCM). Nine species and three varieties are included in the genus of Panax, in which nearly all species have been used for medicinal purposes. Among them, Panax notoginseng (Burk) F. H. Chen, Panax ginseng C. A. Meyer and Panax quinquefolius L. are the most representative and valuable herbs world-wide, with a long history of cultivation. As the main bioactive chemical constituents, saponins with different aglycones are the major components in various Panax spp., and their pharmacological activities are mainly reflected in the effects on blood system, cardio- and cerebro-vascular systems, nervous system, metabolism, and immune regulation. Researchers of Kunming Institute of Botany (KIB), Chinese Academy of Sciences (CAS), have put many efforts into conducting the investigations on Panax species. Herein, we reviewed the research progress on Panax spp. in KIB, CAS, over the past few decades, from the aspects of history and origin, phytochemistry and pharmacological activities.Graphical Abstract: [ABSTRACT FROM AUTHOR]

Twelve indolyl diketopiperazines 1-12 were isolated from the mycelia culture of Aspergillus penicilliodes Speg., a dominant microorganism from the post fermentation process of ripe Pu-er tea. Their structures were elucidated by extensive spectroscopic methods. Among them, trypostatins C (1) and D (2) featuring with a rare methyl vinyl ketone side chain at C-2 are new compounds, while 3 and 4 were obtained for the first time from nature source. The isolates 3-12 did not show obvious cytotoxicities against five human cancer cell lines at a concentration of 40 μM. [ABSTRACT FROM AUTHOR]

Further phytochemical investigation of the steaming treated roots of Panax notoginseng (Araliaceae) led to the identification of two new dammarane-type triterpenoid saponins, notoginsenoside SP20 (1) and SP21 (2). In addition, a pair of new phenolic glycosides (3a and 3b) was also isolated together with two known compounds. Their structures were elucidated by HRESIMS, 1D- and 2D-NMR spectra. Compounds 1 and 2 showed no in vitro cytotoxicity against five human cancer cell lines (HL-60, SMMC-7712, A-549, MCF-9 and SW480). [ABSTRACT FROM AUTHOR]

Fifty-eight phenolic compounds isolated from Phyllanthus emblica were screened and compared for their in vitro and in vivo antioxidant properties, as well as hyaluronidase (HAase) inhibitory activities. Among them, 20 compounds showed to be promising antioxidants due to the stronger scavenging activity in both DPPH radical and Danio rerio reactive oxygen species assays, while nine compounds were potential HAase inhibitors with 100-fold stronger activities than that of the positive control, DSCG. The structure activity relationship was discussed. [ABSTRACT FROM AUTHOR]

Two new compounds, (Z,R)-1-phenylethylcinnamate (1) and (1R,2R,3R,6S)-pipoxide (2) were isolated from the aerial part ofPiper hainanense, along with 12 known compounds, including nine benzene derivatives (4–11), one isobutylamide (12), and two polyoxygenated cyclohexene derivatives (13–14). Their structures were elucidated on the basis of the HRESIMS, 1D and 2D NMR spectroscopic analyses, and ECD in cases of2and3. The absolute configuration of ellipeiopsol B (3) was determined for the first time. All these compounds1–14were reported from the titled plant for the first time. Most of the isolates were tested for their cytotoxicities against five human cancer cell lines. Four of which,2,3,9,14showed moderate bioactivities. Among them, the new compound2showed potential cytotoxicity against SMMC-7721, MCF-7, and SW-480 with IC50values of 9.7, 15.0, and 13.2 μM, respectively. [ABSTRACT FROM PUBLISHER]

A new methylene-bridged dimeric flavonol glycoside, methylenebisnicotiflorin (1), was isolated from ripe Pu-er tea, along with 10 known flavonoids (2–11) and seven known phenolic compounds (12–18). The structure elucidation was based on spectroscopic analysis. Among them, 1,3-dihydroxyphenyl-2-O-sulfate (13), 2,3,4-trihydroxybenzoic acid (16) and 3,3′,4,4′-tetrahydroxybiphenyl (18) are reported from tea plants for the first time. [ABSTRACT FROM PUBLISHER]

Fifteen known compounds including four triterpenoids (1–4), one sterol (5), one diketopiperazine alkaloid (6) and nine phenolics (7–15) were isolated from the stems ofPiper wallichii. Their structures were elucidated by means of spectroscopic analysis, and acidic hydrolysis in case of the 2-oxo-3β,19α,23-trihydroxyurs-12-en-28-oic acid β-D-glucopyranosyl ester (1). The structure of compound1was fully assigned by 1D and 2D NMR experiments for the first time. All isolates were tested for their antibacterial, antifungal, anti-inflammatory and antiplatelet aggregation bioactivities. [ABSTRACT FROM PUBLISHER]

Phytochemical investigation of the rhizomes of Panax japonicus C. A. Meyer (Araliaceae) resulted in the isolation of two new dammarane-type triterpenoid saponins, yesanchinoside R1 ( 1) and yesanchinoside R2 ( 2), together with one new natural product, 6′′′- O-acetylginsenoside Re ( 3). In addition, 25 known compounds, including 23 triterpenoid saponins, 4- 26, β-sitosterol 3- O- β- D-glucopyranoside ( 27), and ecdysterone ( 28), were also identified. The known saponins 12, 15, and 18- 22 were reported for the first time from the title plant. Their structures were elucidated on the basis of detailed spectroscopic analyses, including 1D- and 2D-NMR techniques, as well as acidic hydrolysis. [ABSTRACT FROM AUTHOR]

Arbutin (1), chlorogenic acid (2) and 6′-O-caffeoylarbutin (3) are three major components in Vaccinium dunalianum Wight with various promising bioactivities. A reliable, reproducible and accurate method for simultaneous and quantitative determination of 1–3 is developed by RP-HPLC analysis. This method should be appropriate for the quality assurance of unprocessed and processed materials of V. dunalianum. The contents of 1–3 in different parts of V. dunalianum from different origins were analysed. The content of 3 was much higher than those of 1 and 2, accounting for up to 31.76% in the dried leaf buds. Moreover, the leaf buds, flower buds and leaves showed a tendency towards higher contents of 1–3 than the other plant parts. [ABSTRACT FROM AUTHOR]

6′-O-Caffeoylarbutin, an arbutin derivative, is a naturally occurring glucoside of hydroquinone fromVaccinium 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. [ABSTRACT FROM PUBLISHER]