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PubMed2005

Protective effect of Polygonum multiflorum Thunb on amyloid beta-peptide 25-35 induced cognitive deficits in mice.

Amyloid beta protein (Abeta) may be neurotoxic during the progression of Alzheimer's disease by eliciting oxidative stress. This study was designed to determine the effect of Polygonum multiflorum Thunb water extract (PWE) on Abeta25-35-induced cognitive deficits and oxidative stress in mice. Mice were fed experimental diets comprising either 0.5 or 1% PWE for 4 weeks, and then received a single intracerebroventricular (i.c.v.) injection of Abeta25-35 (10 microg/mouse). Behavioral changes in the mice were evaluated using passive avoidance and water-maze tests. The consumption of PWE significantly ameliorated the cognitive deficits caused by i.c.v. injection of Abeta25-35. The Abeta25-35 treatment accelerated the lipid peroxidation, and PWE attenuated the Abeta-induced increase in brain levels of thiobarbituric acid reactive substances. There was an increase in glutathione peroxidase activity in PWE-treated groups. The acetylcholinesterase activity in the brain and serum was lower in PWE supplemented groups than in the only Abeta-injected group. These findings suggest that PWE exerts a preventive effect against cognitive deficits induced by Abeta25-35 accumulation in Alzheimer's disease, and that this effect is mediated by the antioxidant properties of PWE.

Acetylcholinesterase↗
PubMed2005

Neuroprotective effects of Polygonum multiflorum on nigrostriatal dopaminergic degeneration induced by paraquat and maneb in mice.

The neuroprotective effects of Polygonum multiflorum extract (PME) and its two fractions, ethanol-soluble PME (PME-I) and -insoluble PME (PME-II), on the degeneration of nigrostriatal dopaminergic neurons induced by a combination of paraquat and maneb (PQMB) were investigated in male C57BL/6 mice. The mice were treated twice a week for 6 weeks with intraperitoneal injections of PQMB. This combination caused a reduction of spontaneous locomotor activity, motor incoordination, and declines of dopamine level in the striatum and tyrosine hydroxylase-positive neurons in the substantia nigra. Administration of PME and PME-I once daily for 47 days during 6 weeks of PQMB treatment and last 8 days after PQMB significantly attenuated the impairment of behavioral performance and the decrease in striatal dopamine level and substantia nigral tyrosine hydroxylase-positive neurons in the PQMB-treated animals, whereas the administration of PME-II had no effect on these behavioral, neurochemical and histological indices. The present findings suggest that PME has a beneficial influence on parkinsonism induced by PQMB and that the effects of PME are attributable to some substance(s) included in the ethanol-soluble fraction of PME (PME-I).

3,4-Dihydroxyphenylacetic Acid↗
PubMed2005

Cycloartane type triterpenoids from the rhizomes of Polygonum bistorta.

Two new compounds, 24(E)-ethylidenecycloartanone (1) and 24(E)-ethylidenecycloartan-3alpha-ol (2) were isolated from the rhizomes of Polygonum bistorta, together with seven known compounds viz., cycloartane-3,24-dione (3), 24-methylenecycloartanone (4), gamma-sitosterol (5), beta-sitosterol (6), beta-sitosterone (7), friedelin (8) and 3beta-friedelinol (9). All the cycloartane type triterpenoids, compounds 7 and 8 are reported for the first time from this plant. A combination of 1D and 2D NMR spectroscopy and MS were mainly used to elucidate the structures of the new compounds 1 and 2.

Magnetic Resonance Spectroscopy↗
PubMed2001

Large-scale separation of resveratrol, anthraglycoside A and anthraglycoside B from Polygonum cuspidatum Sieb. et Zucc by high-speed counter-current chromatography.

High-speed counter-current chromatography was successfully applied to the large-scale separation of resveratrol, anthraglycoside A and anthraglycoside B from the crude extract of Polygonum cuspidatum Sieb. et Zucc using a two-phase solvent system composed of chloroform, methanol and water. Resveratrol, anthraglycoside A and anthraglycoside B were separated from multigram quantities (5 g) of crude extract of P. cuspidatum. The separation yielded 200 mg to 1 g of these three compounds each at over 98% purity as determined by HPLC. The chemical structures of these components were identified by nuclear magnetic resonance (NMR) and MS.

Anthracenes↗
PubMed2003

Antioxidant flavonoids from leaves of Polygonum hydropiper L.

Ten flavonoid compounds were isolated from the dried leaves of Polygonum hydropiper L. (Laksa leaves), and identified as 3-O-alpha-L-rhamnopyranosyloxy-3',4',5,7-tetrahydroxyflavone; 3-O-beta-D-glucopyranosyloxy-4',5,7-trihydroxyflavone; 6-hydroxyapigenin; 6"-O-(3,4,5-trihydroxybenzoyl) 3-O-beta-D-glucopyranosyloxy-3', 4', 5, 7-tetrahydroxyflavone; scutillarein; 6-hydroxyluteolin; 3',4',5,6,7-pentahydroxyflavone; 6-hydroxyluteolin-7-O-beta-D-glucopyranoside; quercetin 3-O-beta-D-glucuronide; 2"-O-(3,4,5-trihydroxybenzoyl) quercitrin; quercetin. Evaluation of the antioxidative activity, conducted in vitro, by using electron spin resonance (ESR) and ultraviolet visible (UV-vis) spectrophotometric assays, showed that these isolated flavonoids possess strong antioxidative capabilities. Measurement of the Trolox equivalent antioxidant capacity (TEAC) values, against ABTS (2,2'-azinobis(3-ethyl-benzo-thiazoline-6-sulphonic acid) radicals and phenyl-tert-butyl nitrone (PBN) azo initiator (AI) also showed strong anti-oxidative activity. The most powerful of the antioxidants was 2"-O-(3,4,5-trihydroxybenzoyl) quercitrin (galloyl quercitrin). A combination of two flavonoid compounds was tested for synergistic anti-oxidative capacity, but no significant improvement was observed.

Antioxidants↗
PubMed2003

Investigation of heavy metal accumulation in Polygonum thunbergii for phytoextraction.

In this study, cadmium (II), lead (II), copper (II) and zinc (II) were determined in Polygonum thunbergii and soil from the Mankyung River watershed, Korea. Soil samples contained detectable lead (<17.5 g g(-1)), copper (<8.4 g g(-1)) and zinc (<24.5 g g(-1)), whereas cadmium was undetectable. Whole plants of P. thunbergii contained detectable lead (<320.8 g g(-1)), copper (<863.2 g g(-1)) and zinc (<2427.3 g g(-1)), whereas cadmium was detectable only in the stem (<7.4 g g(-1)) and root (<10.1 g g(-1)). Whole plant concentrations were very different for each metal, particularly in the case of zinc. The mean content of heavy metal in the whole plants increased in the order of cadmium (8.5 g g(-1))<lead (183.3 g g(-1))<copper (548.1 g g(-1))<zinc (1506.7 g g(-1)). Soil lead, copper and zinc were correlated with each metal's accumulation in the plants (lead, r = 0.841, P<0.005; copper, r = 0.874, P<0.001; zinc, r = 0.770, P<0.005). Lead content in roots and leaves was highly correlated (r = 0.5529, P<0.001), as was lead content in roots and stems (r = 0.5425, P<0.001). Mean bioconcentration factors for the aboveground tissues were 4.2 (lead), 14.8 (copper) and 27.7 (zinc), and for the underground tissues, were 22.2 (lead), 92.9 (copper) and 62.7 (zinc). After hydroponic growth, bioaccumulation coefficients were 2.0 (cadmium), 3.2 (lead), 17.2 (copper) and 13.1 (zinc) for whole plants. We considered these results as indicative of the ability of P. thunbergii plants to take up metal ions from a soil matrix contaminated with heavy metals.

Biodegradation, Environmental↗
PubMed2002

Antinociceptive activity of Polygonum hydropiper.

The hexane, ethylacetate and methanol extracts of Polygonum hydropiper whole plant administered to mice at doses of 250 and 500 mg/kg, showed a significant activity on acetic acid-induced writhing. Within the tested extracts, the ethylacetate one showed the most significant activity.

Analgesics↗
PubMed2002

Process balance and product quality in the production of natural indigo from Polygonum tinctorium Ait. applying low-technology methods.

Indigo is the most important blue component in the class of natural dyes for cellulose and protein fibres. In the moderate European climate Polygonum tinctorium Ait. could be an interesting source for natural indigo (Vat blue 1). Following a cultivation of the plant material a simple procedure for the extraction of the indigo precursor indican was investigated with regard to crop and quality of dye obtained. The dependence of the crop on the storage conditions of the harvested plant material was investigated. The results quantify the distinct sensitivity of the fresh material to the time of storage before extraction with regard to the amount of natural indigo obtained, the photometrically determined indigo content in the product and the shade and colour depth observed in standardised dyeing experiments. A basic set of data is presented, which describes the process in terms of consumption of energy, water and chemicals and organic waste released from the extraction step.

Color↗
PubMed2006

[Effects of exogenous phytohormones on hairy root growth and biosynthesis of anthraquinones in the hairy root culture of Polygonum multiflorum].

The effects of exogenous phytohormones on hairy root growth and biosynthesis of anthraquinones in the hairy root cultures of Polygonum multiflorum Thunb. were studied. The results showed that the 2,4-D, NAA and 6-BA all have obvious effects on the growth of hairy root cultures and the biosynthesis of anthraquinones. The growth of hairy root and biosynthesis of anthraquinones were strongly restrained by 2,4-D. However, NAA and 6-BA of appropriate concentration were favourable to hairy root growth and anthraquinones production.

2,4-Dichlorophenoxyacetic Acid↗
PubMedDate not supplied

Beta-glucosidase-catalyzed hydrolysis of indican from leaves of Polygonum tinctorium.

In this article, a HPLC method to identify and quantify the dyes and the indigo precursors produced in Polygonum tinctorium is described. Using this technique, indican has been positively identified in extracts of P. tinctorium. Our work with two cultivars of P. tinctorium has confirmed that the quantity of indican is dependent on the cultivars, harvest period, and age of the leaves. Two enzymes, Novozym 188 (cellobiase) and Novarom G (beta-glucosidase), are compared on the basis of their activities to hydrolyze the indican at several pH values. We observed that Novarom G is more active than Novozym 188 whatever the pH and that optimum pH of both enzymes for indican hydrolysis is 3. Liberated indoxyl can be oxidized in alkaline media and transformed into indigo and indirubin.

Catalysis↗
PubMedDate not supplied

A new HPLC-ELSD method to quantify indican in Polygonum tinctorium L. and to evaluate beta-glucosidase hydrolysis of indican for indigo production.

A method to quantify the indigo precursor indican (indoxyl-beta-D-glucoside) in Polygonum tinctorium L. has been developed. Plant material was extracted in deionized water, and indican was identified and quantified using high performance liquid chromatography (HPLC) coupled to an evaporative light scattering detector (ELSD). Results confirmed that with this method it is possible to measure indican content in a short time, obtaining reliable and reproducible data. Using this method, leaf indican content was quantified every 15 days during the growing season (from May to October) in P. tinctorium crops grown in a field experiment in Central Italy. Results showed that indican increased along the growing season until flowering and was positively affected by photosynthetic active radiation (PAR). Indican is naturally hydrolyzed by native beta-glucosidase to indoxyl and glucose, the indoxyl yielding indigo. The activity of two enzymes, sweet almond beta-glucosidase and Novarom G preparation, were compared with P. tinctorium native beta-glucosidase to evaluate indigo production. Results showed that the ability to promote indigo formation increased as follows: almond beta-glucosidase <or= Novarom G.

Chromatography, High Pressure Liquid↗
PubMed2004

Environmental factors affecting productivity, indican content, and indigo yield in Polygonum tinctorium Ait., a subtropical crop grown under temperate conditions.

Polygonum tinctorium Ait. is a herbaceous subtropical annual plant, belonging to the family Polygonaceae. Within the cells of its leaves P. tinctorium accumulates large amounts of a colorless glycoside, indican (indoxyl beta-d-glucoside), from which the blue dye indigo is synthesized. P. tinctorium is well-known in Japan, where it had been cultivated to produce natural indigo for textile dyeing, whereas it represents a potentially interesting new crop in Europe. To better understand the effects of environmental parameters on P. tinctorium crop production and indigo yield, field experiments were carried out in central Italy under temperate climate. Three lines were tested during the 2001 and 2002 growing seasons, and plant/leaf yields as well as indican contents were evaluated. The results showed that P. tinctorium grown in temperate climate conditions can be harvested three times a year. Yields of 82 and 120 t ha(-1) of fresh plant yield were obtained in 2001 and 2002, respectively. The contrasting weather conditions between the two years significantly affected biomass production, which was higher in the 2002 season, characterized by wet weather conditions. The cycle length from sowing to the last harvest was accomplished in 229-238 days when plants had accumulated 2017-2018 degrees C. Green leaves accounted for 40-45% by weight of fresh plant tissue and contained 11-20 g kg(-1) indican. The three lines did not significantly differ in the main productive parameters or in fresh leaf indican content (14.1 g kg(-1) mean value). Photosynthetic active radiation influences indican leaf production according to the model y = 0.0004x + 8.566 (P < 0.01, correlation coefficient = 0.818). Indican content ranged from 12 to 25 g kg(-1) of fresh leaves with PAR daily values from 10000 to 40000 mEinstein m(-2) (recorded in May and at the end of July-beginning of August, respectively). The results indicate that in nonlimiting rainfall conditions a very high indican content and a potentially high indigo yield can be obtained by cultivating P. tinctorium in this pioneer geographical area.

Climate↗
PubMed2001

New phenylpropanoid esters of sucrose from Polygonum lapathifolium.

Four new phenylpropanoid esters of sucrose, lapathosides A (1), B (2), C (3), and D (4), were isolated from the aerial parts of Polygonum lapathifolium together with known esters, vanicoside B (5) and hydropiperoside (6). The structures of 1-4 were determined by spectral (1D and 2D NMR and MS) analysis. Lapathoside A (1) and vanicoside B (2) showed significant inhibitory effects on the Epstein-Barr virus early antigen activation by tumor-promoters.

Animals↗
PubMed2006

A new tannin-related compound from the rhizome of Polygonum bistorta L.

A new tannin-related compound named bistortaside A (1) and a known compound have been isolated from the rhizome of Polygonum bistorta L. A new compound was elucidated as 3-methyl-gallic acid 4-O-beta-d-(6'-O-3''-methyl-galloyl)-glucopyranoside and a known compound was quercetin-3'-O-beta-d-glucopyranoside (2) on the basis of spectroscopic analysis.

Molecular Structure↗
PubMed2002

Barriers to sexual reproduction in Polygonum viviparum: a comparative developmental analysis of P. viviparum and P. bistortoides.

Polygonum viviparum is widely distributed in arctic and alpine regions of the northern hemisphere. Fruit set has never been observed in North American populations and has been reported only very rarely in Europe. Although this species is extremely well studied, the impediments to successful fruit production are unknown. We investigated the sexual reproductive process in P. viviparum growing in the southern Colorado Rocky Mountains. For comparison, we also examined this process in the sympatric congener P. bistortoides, in which reproduction is exclusively sexual. Lack of viable fruit production in P. viviparum has no single developmental explanation; defects occur in each of the processes and structures associated with sexual reproduction studied, yet, these processes and structures also appear to function normally in at least some flowers or individuals. Development is abnormal in many ovules of P. viviparum, however, comparison with P. bistortoides shows that these abnormalities do not contribute to differences in seed production between the two species. The virtual absence of sexual reproduction in P. viviparum appears to be due largely to a low rate of fertilization and to embryo/fruit abortion.

Arctic Regions↗
PubMed2006

Acute hepatitis due to shen-min: a herbal product derived from Polygonum multiflorum.

Shen-Min is a herbal product sold as a supplement for women to enhance hair growth. It is widely available across Asia, Europe, and the United States and sold without prescription as a hair nutritional supplement. We describe a case of acute liver injury in a 28-year-old white woman who developed symptomatic hepatitis 8 weeks after starting Shen-Min. All other potential causes of acute hepatitis including viral, hypoxic/ischemic, metabolic, and autoimmune etiologies were excluded. The liver injury slowly resolved over 3 weeks after discontinuing the herbal product. Although the mechanism of Shen-Min hepatotoxicity is unknown, we suspect an idiosyncratic reaction because the patient developed a fine maculopapular rash, mild eosinophilia, and did not overdose. Shen-Min is a Chinese herbal product with a mixture of several plants and vitamins including Polygonum multiflorum, a root that has been previously associated with hepatotoxicity. Nonetheless to our knowledge this is the first reported case of herbal-induced hepatotoxicity in a patient taking Shen-Min per se. Clinicians taking care of patients with acute hepatitis of unclear etiology should be aware that the consumption of Shen-Min, a hair supplement widely available in the United States and Western countries might cause acute hepatitis.

Acute Disease↗
PubMed2005

Changes in the light sensitivity of buried Polygonum aviculare seeds in relation to cold-induced dormancy loss: development of a predictive model.

The effect of cold (stratification) temperature on changes in the sensitivity of Polygonum aviculare seeds to light was investigated. Seeds buried in pots were stored under stratification temperatures (1.6, 7 and 12 degrees C) for 137 d. Seeds exhumed at regular intervals during storage were exposed to different light treatments. Germination responses obtained for seeds exposed to different light treatments and stratification temperatures were used to develop a model to predict the sensitivity of buried seeds to light. Seed sensitivity to light increased as dormancy loss progressed, showing the successive acquisition of low-fluence responses (LFR), very low-fluence responses (VLFR), and the loss of the light requirement for germination for a fraction of the seed population. These changes were inversely correlated to stratification temperature, allowing the use of a thermal time index to relate observed changes in seed light sensitivity to stratification temperature. The rate of increase in sensitivity of P. aviculare seeds to light during stratification is inversely correlated to soil temperature, and these changes in light sensitivity could be predicted in relation to temperature using thermal-time models.

Cold Temperature↗
PubMed2003

Polygonum multiflorum extracts improve cognitive performance in senescence accelerated mice.

The objective of this study was to investigate the effects of Polygonum multflorum (PM) Thunb. on the learning and memory ability in one and seven-month-old male senescence accelerated mice (SAMP8). The mice were fed with two different diets for 18 weeks; they were casein dietary group (control group) and casein diet supplemented with PM extracts. Active shuttle avoidance test was performed to determine the learning and memory ability of the mice while the spongy degeneration and the lipofuscin, malondialdehyde, and total thiol levels of the brain were measured to evaluate the extent of the brain degeneration and oxidative status. Results of active shuttle avoidance test showed the mice fed with the PM extracts had significantly better learning and memory ability than the control group. The spongy degeneration and the lipofuscin and malondialdehyde concentrations of the mice in the PM groups were significantly lower than the control in both age groups, whereas the total thiol levels were higher but not significantly different. It was concluded that the supplement of the PM extracts could improve the learning and memory ability and reduce the brain pathological changes in mice. This might be due to the antioxidant phytochemicals of the PM extracts.

Aging↗