Biological activities and distribution of plant saponins.

Epidemiological evidence suggests that flavonoids may play an important role in the decreased risk of chronic diseases associated with a diet rich in plant-derived foods. Flavonoids are also common constituents of plants used in traditional medicine to treat a wide range of diseases. The purpose of this article is to summarize the distribution and biological activities of one of the most common flavonoids: luteolin. This flavonoid and its glycosides are widely distributed in the plant kingdom; they are present in many plant families and have been identified in Bryophyta, Pteridophyta, Pinophyta and Magnoliophyta. Dietary sources of luteolin include, for instance, carrots, peppers, celery, olive oil, peppermint, thyme, rosemary and oregano. Preclinical studies have shown that this flavone possesses a variety of pharmacological activities, including antioxidant, anti-inflammatory, antimicrobial and anticancer activities. The ability of luteolin to inhibit angiogenesis, to induce apoptosis, to prevent carcinogenesis in animal models, to reduce tumor growth in vivo and to sensitize tumor cells to the cytotoxic effects of some anticancer drugs suggests that this flavonoid has cancer chemopreventive and chemotherapeutic potential. Modulation of ROS levels, inhibition of topoisomerases I and II, reduction of NF-kappaB and AP-1 activity, stabilization of p53, and inhibition of PI3K, STAT3, IGF1R and HER2 are possible mechanisms involved in the biological activities of luteolin.

Distribution and biological activities of the flavonoid luteolin.

https://nph.onlinelibrary.wiley.com/doi/pdf/10.1111/j.1469-8137.2010.03269.x

Multiple functional roles of flavonoids in photoprotection.

Ginsenosides are a special group of triterpenoid saponins that can be classified into two groups by the skeleton of their aglycones, namely dammarane‐ and oleanane‐type. Ginsenosides are found nearly exclusively in Panax species (ginseng) and up to now more than 150 naturally occurring ginsenosides have been isolated from roots, leaves/stems, fruits, and/or flower heads of ginseng. Ginsenosides have been the target of a lot of research as they are believed to be the main active principles behind the claims of ginsengs efficacy. The potential health effects of ginsenosides that are discussed in this chapter include anticarcinogenic, immunomodulatory, anti‐inflammatory, antiallergic, antiatherosclerotic, antihypertensive, and antidiabetic effects as well as antistress activity and effects on the central nervous system. Ginsensoides can be metabolized in the stomach (acid hydrolysis) and in the gastrointestinal tract (bacterial hydrolysis) or transformed to other ginsenosides by drying and steaming of ginseng to more bioavailable and bioactive ginsenosides. The metabolization and transformation of intact ginsenosides, which seems to play an important role for their potential health effects, are discussed. Qualitative and quantitative analytical techniques for the analysis of ginsenosides are important in relation to quality control of ginseng products and plant material and for the determination of the effects of processing of plant material as well as for the determination of the metabolism and bioavailability of ginsenosides. Analytical techniques for the analysis of ginsenosides that are described in this chapter are thin‐layer chromatography (TLC), high‐performance liquid chromatography (HPLC) combined with various detectors, gas chromatography (GC), colorimetry, enzyme immunoassays (EIA), capillary electrophoresis (CE), nuclear magnetic resonance (NMR) spectroscopy, and spectrophotometric methods.

Ginsenosides: Chemistry, biosynthesis, analysis and potential health effects

Barberry (Berberis vulgaris L. family Berberidaceae) is well known in Iran and various parts of this plant including its root, bark, leaf and fruit have been used as folk medicine. The two decades of research has demonstrated different pharmacological and therapeutic effects of B. vulgaris and its isoquinoline alkaloids (particularly berberine). Studies carried out on the chemical composition of the plant show that the most important constituents of this plant are isoquinoline alkaloids such as berberine, berbamine and palmatine. Berberine represents one of the most studied among the naturally occurring protoberberine alkaloids. In addition to B. vulgaris (barberry), berberine is present in many other plants and is used for the treatment of different diseases. This article reviews the traditional uses and pharmacological effects of total extract and the most active ingredient of B. vulgaris (berberine).

Pharmacological and therapeutic effects of Berberis vulgaris and its active constituent, berberine.

Methanol, methanol-water (1:1) and water extracts were prepared from seventy-seven Vietnamese medicinal plants and tested for their antiproliferative activities against human HT-1080 fibrosarcoma cells. Among them, fifteen extracts including seven methanol extracts of Caesalpinia sappan, Catharanthus roseus, Coscinium fenestratum, Eurycoma longifolia, Hydnophytum formicarum and Streptocaulon juventas (collected at two areas), six methanol-water (1:1) extracts of Cae. sappan, Cat. roseus, Co. fenestratum, H. formicarum and S. juventas (at two areas), and two water extracts of Cae. sappan and S. juventas exhibited antiproliferative activities in a concentration-dependent manner. Their antiproliferative activities against human cervix HeLa adenocarcinoma, human lung A549 adenocarcinoma, murine colon 26-L5 carcinoma, murine Lewis lung carcinoma (LLC) and murine B16-BL6 melanoma cells were then examined. Co. fenestratum showed selective activity against lung carcinoma and/or lung metastatic cell lines, A549, LLC and B16-BL6, while H. formicarum and S. juventas showed selective activity against human tumor cell lines, HeLa and A549. Characteristic morphological change and DNA fragmentation indicated the antiproliferative activity to be due to the induction of apoptosis.

/pdf/antiproliferative-activity-of-vietnamese-medicinal-plants-1b20g7jgqv.pdf

Antiproliferative activity of Vietnamese medicinal plants.

Among 288 extracts, prepared from 96 medicinal plants used in Vietnamese traditional medicine to treat gout and related symptoms, 188 demonstrated xanthine oxidase (XO) inhibitory activity at 100 μg/ml, with 46 having greater than 50% inhibition. At 50 μg/ml, 168 of the extracts were active, with 21 possessing more than 50% inhibition. At 25 μg/ml, 146 extracts exhibited inhibitory activity, with 8 showing over 50% inhibition, while 126 extracts presented activity at 10 μg/ml, with 2 having greater than 50% inhibition. The MeOH extracts of Artemisia vulgaris, Caesalpinia sappan (collected at the Seven-Mountain area), Blumea balsamifera (collected in Lam Dong province), Chrysanthemum sinense and MeOH–H2O extract of Tetracera scandens (Khanh Hoa province) exhibited strong XO inhibitory activity with IC50 values less than 20 μg/ml. The most active extract was the MeOH extract of the flower of C. sinense with an IC50 value of 5.1 μg/ml. Activity-guided fractionation of the MeOH extract led to the isolation of caffeic acid (1), luteolin (2), eriodictyol (3), and 1,5-di-O-caffeoylquinic acid (4). All these compounds showed significant XO inhibitory activity in a concentration-dependent manner, and the activity of 2 was more potent (IC50 1.3 μM) than the clinically used drug, allopurinol (IC50 2.5 μM).

Xanthine Oxidase Inhibitory Activity of Vietnamese Medicinal Plants

Bioassay-guided fractionation of the water extract of the rhizomes of Dioscorea spongiosa led to the isolation and identification of new diarylheptanoids, diospongins A - C, together with three known lignans. Their structures, including absolute stereochemistry, were determined by analyses of NMR data, chemical conversions and CD spectrum. The isolated compounds, except for diospongin A, exerted potent inhibitory activities on bone resorption induced by parathyroid hormone in a bone organ culture system.

New diarylheptanoids from the rhizomes of Dioscorea spongiosa and their antiosteoporotic activity

In vitro antiplasmodial activity of antimalarial medicinal plants used in Vietnamese traditional medicine

The methanol extract of Vietnamese ginseng (Panax vietnamensis) was found to possess hepatocytoprotective effects on D-galactosamine (D-GalN)/tumor necrosis factor-alpha (TNF-alpha)-induced cell death in primary cultured mouse hepatocytes Further chemical investigation of the extract afforded two new dammarane-type triterpene saponins, ginsenoside Rh(5) (1) and vina-ginsenoside R(25) (2), as well as eight known dammarane-type triterpene saponins, majonoside R(2) (3), pseudo-ginsenoside RT(4) (4), vina-ginsenosides R(1) (5), R(2) (6), and R(10) (7), ginsenosides Rg(1) (8), Rh(1) (9), and Rh(4) (10), and a known sapogenin protopanaxatriol oxide II (11) Their structures were elucidated on the basis of spectral analysis In addition, by the using LC-electrospray ionization (ESI)-MS method, five known saponins, ginsenosides Rb(1), Rb(2), Rc, Rd, and Re (12--16), were also identified in the extract Among the compounds isolated, majonoside R(2) (3), the main saponin in Vietnamese ginseng, showed strong protective activity against D-GalN/TNF-alpha-induced cell death in primary cultured mouse hepatocytes This demonstrates that the hepatocytoprotective effect of Vietnamese ginseng is due to dammarane-type triterpene saponins that have an ocotillol-type side chain, a characteristic constituent of Vietnamese ginseng

Quan Le Tran

Papers

Antiproliferative activity of Vietnamese medicinal plants.

Xanthine Oxidase Inhibitory Activity of Vietnamese Medicinal Plants

New diarylheptanoids from the rhizomes of Dioscorea spongiosa and their antiosteoporotic activity

In vitro antiplasmodial activity of antimalarial medicinal plants used in Vietnamese traditional medicine

Triterpene saponins from Vietnamese ginseng (Panax vietnamensis) and their hepatocytoprotective activity.