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PubMed2003

Screening pharmaceutical preparations containing extracts of turmeric rhizome, artichoke leaf, devil's claw root and garlic or salmon oil for antioxidant capacity.

Pharmaceutical preparations derived from natural sources such as vegetables often contain compounds that contribute to the antioxidant defence system and apparently play a role in the protection against degenerative diseases. In the present study, commercial preparations containing extracts of turmeric, artichoke, devil's claw and garlic or salmon oil were investigated. The products were divided into fractions of different polarity, and their antioxidant activity was determined using the Trolox equivalent antioxidant capacity (TEAC) assay. This test is based on the efficacy of the test material to scavenge 2,2'-azino-bis(3-ethylbenzthiazoline-6-sulfonic acid) (ABTS) derived radicals. Total phenols were determined in all fractions as well as specific carotenoids in the most lipophilic fraction to assess their contribution to the antioxidant activity. For comparison, the radical scavenging effect of selected constituents of the extracts such as curcumin, luteolin, kaempferol, chlorogenic acid, harpagoside, beta-carotene and alpha-tocopherol was investigated and compared with that of Trolox. Curcumin, luteolin, kaempferol, chlorogenic acid and beta-carotene showed an antioxidant activity superior to Trolox in the TEAC assay; harpagoside was barely active. All fractions of the turmeric extract preparation exhibited pronounced antioxidant activity, which was assigned to the presence of curcumin and other polyphenols. The antioxidant activity corresponding to the artichoke leaf extract was higher in the aqueous fractions than in the lipophilic fractions. Similarly, devil's claw extract was particularly rich in water-soluble antioxidants. Harpagoside, a major compound in devil's claw, did not contribute significantly to its antioxidant activity. The antioxidant capacity of the garlic preparation was poor in the TEAC assay. That of salmon oil was mainly attributed to vitamin E, which is added to the product for stabilization. In all test preparations, the antioxidant activity was significantly correlated with the content of total phenolic compounds.

Antioxidants↗
PubMed2005

Free radical scavenging potential of Saussarea costus.

Saussurea costus (Falc.) Lipschitz from the family Asteraceae is an important medicinal drug, the roots of which are widely used in folk medicine. The antioxidant activity of the plant has been studied using its ability to scavenge DPPH, nitric oxide, superoxide radicals along with its ability to inhibit lipid peroxidation and GSH oxidation. The 1 mg mL(-1) extract had antioxidant activity with 85.2% reduction of DPPH and a 72.7% decrease in lipid peroxidation. It showed maximum inhibition of superoxide radical of 66.0%, and 58.4% inhibition of nitric oxide formation. The concentration of chlorogenic acid was 0.027% in the extract of S. costus. Thus, the therapeutic activity of the plant may be due to its antioxidant activity, probably as a result of the presence of chlorogenic acid.

Animals↗
PubMed2026

Integrated phytochemical and bioactivity profiling of Xanthium strumarium fruits from Korea and China: Implications for origin-specific quality specification.

BACKGROUND: Geographic origin influences the phytochemical composition and biological activities of medicinal plant resources. Xanthium strumarium L. (XS) fruit is widely used in East Asian traditional medicine. However, current pharmacopeial standards primarily recognize Chinese-derived material, despite the availability and traditional use of XS in Korea. To address this gap and support origin-informed quality specification, we compared fruits from Korea (XS-K) and China (XS-C) using chloroplast genome sequencing, targeted phytochemical profiling (high-performance liquid chromatography (HPLC) for selected phenolics and gas chromatography-flame ionization detection (GC-FID) for fatty acids and phytosterols, and multivariate chemometric analysis. RESULTS: Chloroplast genome analysis revealed high overall similarity but localized divergence around the rpoC2 locus and a greater mutation burden in XS-C, supporting origin-associated genomic differentiation. Phytochemical profiling revealed distinct origin-dependent metabolic signatures. XS-K showed higher levels of phytosterols, chlorogenic acid, 4,5-dicaffeoylquinic acid (4,5-DCQ), and xanthatin was detected only in XS-K, whereas XS-C exhibited greater abundance of total fatty acids, particularly oleic acid. Unsupervised clustering and log2 fold-change ranking confirmed clear compositional separation, and variable importance in projection (VIP) analysis identified chlorogenic acid, β-sitosterol, oleic acid, 4,5-DCQ, and xanthatin as major discriminators between origins. Bioactivity assays demonstrated that XS-K exerted stronger antioxidant effects in ABTS, DPPH and FRAP assays, stronger skin-related enzyme inhibition, and greater antibacterial activity against Staphylococcus aureus, consistent with its enriched phenolic and sterol profile. CONCLUSION: Together, chloroplast sequence variation, targeted metabolite quantification, and screening bioassays consistently distinguished XS-K from XS-C. These findings support the use of candidate markers for the origin-based authentication and quality control of XS fruit-derived ingredients. © 2026 The Author(s). Journal of the Science of Food and Agriculture published by John Wiley & Sons Ltd on behalf of Society of Chemical Industry.

Fruit↗
PubMed2005

Free radical scavengers and antioxidants from Lemongrass (Cymbopogon citratus (DC.) Stapf.).

Methanol, MeOH/water extracts, infusion, and decoction of Cymbopogon citratus were assessed for free radical scavenging effects measured by the bleaching of the 1,1-diphenyl-2-picryl-hydrazyl (DPPH) radical, scavenging of the superoxide anion, and inhibition of the enzyme xanthine oxidase (XO) and lipid peroxidation in human erythrocytes. The extracts presented effect in the DPPH and superoxide anion assay, with values ranging between 40 and 68% and 15-32% at 33 and 50 microg/mL, respectively, inhibited lipid peroxidation in erythrocytes by 19-71% at 500 microg/mL and were inactive toward the XO at 50 microg/mL. Isoorientin, isoscoparin, swertiajaponin, isoorientin 2' '-O-rhamnoside, orientin, chlorogenic acid, and caffeic acid were isolated and identified by spectroscopic methods. Isoorientin and orientin presented similar activities toward the DPPH (IC(50): 9-10 microM) and inhibited lipid peroxidation by 70% at 100 microg/mL. Caffeic and chlorogenic acid were active superoxide anion scavengers with IC(50) values of 68.8 and 54.2 microM, respectively, and a strong effect toward DPPH. Caffeic acid inhibited lipid peroxidation by 85% at 100 microg/mL.

Antioxidants↗
PubMed1994

Dietary effects on the uptake of benzo[a]pyrene.

It has been established that exposure to polycyclic aromatic hydrocarbons (PAHs), or more specifically benzo[a]pyrene (B[a]P), either by inhalation through cigarette smoking or by contact through occupational exposure of the lungs or skin, can result in cancerous lesions. It appears that the general population consumes more B[a]P from food than from smoking. Despite this, epidemiological studies have not implicated B[a]P from foods as a causative factor in some human cancers. This lack of an epidemiological correlation between cancer incidence and intake of dietary PAHs/B[a]P could be due to some 'protective' or 'detoxification' mechanism. Despite the abundance of literature regarding the food content of B[a]P, there are few data concerning its uptake from foods. In the present study we investigated the intestinal absorption of B[a]P from foods using bile duct cannulated rats and radioactive B[a]P. [14C]B[a]P was first added to solvents such as water, corn oil, liquid paraffin or 50% ethanol, which were the administered by gavage to rats fed diets with or without added carbon. Additionally, food polyphenols such as quercetin and chlorogenic acid were also tested for their effect on the absorption of B[a]P. The results indicated that the excretion of B[a]P in the bile was reduced by water, carbon, quercetin and chlorogenic acid but was potentiated by corn oil. To complement the in vivo studies, some in vitro tests to investigate the efficiency of B[a]P extraction from different foods using water or oil as solvents were also performed. These tests indicated that extraction of B[a]P from foods was affected by the solvent. It is postulated that reduced solubility, physical adsorption and the formation of chemical adducts between B[a]P and some food ingredients, play a sporadic, although still not well determined, role in reducing the absorption of B[a]P from the gut. The results of these studies suggest that B[a]P absorption from the intestinal tract is markedly affected by dietary components, and that this may be a factor that contributes to the lack of an epidemiological correlation between some human cancers and the B[a]P content of foods.

Animals↗
PubMed2005

Characterization of a metal-chelating substance in coffee.

A metal-chelating substance in brewed coffee was separated and characterized by its chemical structure. This substance was a brown polymer. The contents of sugars, amino acids and phenolics in the substance were evaluated. This polymer contained small amounts of sugars and amino acids in its partial structure. After being decomposed by alkaline fusion, the decomposition products were identified by HPLC and GC-MS. Several phenolics were detected in the decomposed products. To characterize this substance, various types of model compounds were prepared by roasting chlorogenic acid, sucrose, and (or) protein with cellulose powder. Among these model compounds, the polymer-forming ability was highest in the model prepared from all four of materials, but the metal-chelating ability was the highest in the model prepared from chlorogenic acid and cellulose. These results suggest that this metal-chelating substance was a melanoidin-like polymer formed by the decomposition and polymerization of sugars, amino acids and phenolics.

Chelating Agents↗
PubMed1996

Cytotoxic components of bardanae fructus (goboshi).

Bardanae Furctus (Goboshi) extract showed potent in vitro cytotoxicity and in vivo antitumor activity against human hepatoma HepG2 cells and mouse sarcoma 180 cells, respectively. In this study, the cytotoxicities of four fractions and three major components (arctiin, arctigenin, and chlorogenic acid) isolated from Goboshi extract were examined. Arctiin and arctigenin, which were contained in the ethylacetate fraction and n-butanol fraction, respectively, showed strong cytotoxicity against HepG2 cells, but little toxicity against Chang liver cells. Chlorogenic acid isolated from the water fraction did not affect the viability of these cells. The cytotoxicity of arctigenin against Chang liver cells was markedly potentiated by treatment with glutathione (GSH) synthesis inhibitor, L-buthionine-(S,R)-sulfoximine (BSO). On the other hand, in HepG2 cells, the cytotoxicity of arctigenin was hardly changed by BSO. The cytotoxicity of arctigenin against HepG2 cells increased in an exposure-time dependent manner. These characteristics of arctigenin were similar to those of Goboshi extract, as previously observed. We therefore conclude that the principal cytotoxic components of Goboshi extract are arctiin and its aglycone arctigenin.

Animals↗
PubMed2006

Phenolic acids in Fructus Xanthii and determination of contents of total phenolic acids in different species and populations of Xanthium in China.

OBJECTIVE: To study the chemical constituents of Fructus Xanthii and to determine the contents of total phenolic acids (TPA) in fruits of Xanthium from different populations for evaluating the quality of them. METHODS: Components in Fructus Xanthii were isolated and purified by various column chromatographies and the contents of TPA were determined by ultraviolet spectrophotometry with chlorogenic acid (CHA) as reference substance. RESULTS: Six caffeoylquinic acids along with caffeic acid and ferulic acid were isolated from Fructus Xanthii. The contents of TPA of the samples collected from 29 populations in China varied from 0.31% to 1.44%. Among the samples originated from two species and 1 variety of Xanthium, the contents of TPA in X. sibiricum var. subinerme samples with an average of 0.36% were relatively lower than those in other 2 species. While the content of TPA in Sample 3 collected from Shanghai was 1.44% and the highest among all the samples, and that in Sample 12 from Xinjian of Jiangxi Province was 0.38% and the lowest among the X. sibiricum samples. CONCLUSION: 5-O-caffeoylquinic acid, 1,4-di-O-caffeoylquinic acid and 4,5-di-O-caffeoylquinic acid were isolated from Xanthium plant for the first time. The difference of contents of TPA in samples from different species and different populations in China was relatively significant. Fructus Xanthii in Shanghai and Sanming of Fujian Province were considered high quality if contents of TPA were used as reference for quality evaluating.

Caffeic Acids↗
PubMed2003

Caffeic acid derivatives in the roots of yacon (Smallanthus sonchifolius).

Five caffeic acid derivatives were found in the roots of yacon, Smallanthus sonchifolius (Poepp. and Endl.) H. Robinson, Asteraceae, as the major water-soluble phenolic compounds. The structures of these compounds were determined by analysis of spectroscopic data. Two of these were chlorogenic acid (3-caffeoylquinic acid) and 3,5-dicaffeoylquinic acid, common phenolic compounds in plants of the family Asteraceae. Three were esters of caffeic acid with the hydroxy groups of aldaric acid, derived from hexose. The structure of the aldaric moiety was determined by hydrolysis and comparison of NMR spectra with those of standard aldaric acids. The compounds were novel caffeic acid esters of altraric acid: 2,4- or 3,5-dicaffeoylaltraric acid, 2,5-dicaffeoylaltraric acid, and 2,3,5- or 2,4,5-tricaffeoylaltraric acid.

Asteraceae↗
PubMed1994

Increased disease susceptibility of transgenic tobacco plants with suppressed levels of preformed phenylpropanoid products.

It has been proposed that natural products synthesized by plants contribute to their resistance to pests and pathogens. We show here that transgenic tobacco plants with suppressed levels of the phenylpropanoid biosynthetic enzyme phenylalanine ammonia-lyase (L-phenylalanine ammonia-lyase, EC 4.3.1.5) and correspondingly low levels of chlorogenic acid, the major soluble leaf phenylpropanoid product, exhibit more rapid and extensive lesion development than wild-type plants after infection by the virulent fungal pathogen Cercospora nicotianae. These observations provide direct evidence that phenylpropanoid products contribute to disease limitation. No induction of transcripts encoding phenylalanine ammonia-lyase or the lignin branch pathway enzyme caffeic acid O-methyltransferase was observed during the infection and there was no perturbation in the pattern of soluble phenylpropanoids. Hence, increased disease susceptibility does not involve inhibition of a pathogen-induced response but likely reflects inhibition of the developmental accumulation of chlorogenic acid. Demonstration of the contribution of such preformed protectants to plant health identifies attractive targets for manipulation by breeding or gene transfer to reduce the quantitative impact of disease.

Disease Susceptibility↗
PubMed2005

Apples increase nitric oxide production by human saliva at the acidic pH of the stomach: a new biological function for polyphenols with a catechol group?

Dietary inorganic nitrate is secreted in saliva and reduced to nitrite by bacterial flora. At the acidic pH of the stomach nitrite is present as nitrous acid in equilibrium with nitric oxide (*NO), and other nitrogen oxides with nitrating and nitrosating activity. *NO in the stomach exerts several beneficial effects, but nitrosating/nitrating species have been implicated as a possible cause of epithelial neoplasia at the gastroesophageal junction. We investigated the effects of apple extracts on *NO release by human saliva at pH 2. A water extract obtained from apple homogenate increased *NO release caused by acidification of saliva. Data show that polyphenols were responsible for this activity, with chlorogenic acid and (+)-catechin the most active and concentrated species. However, ferulic acid, a hydroxycinnamic acid with only one aromatic hydroxyl group, did not increase *NO release. Fructose, the most representative sugar in apples, was also inactive. Interestingly, ascorbic acid in saliva induced a SCN(-)-enhanced burst of *NO but, unlike apple, the release was transient. The simultaneous addition of ascorbic acid and apple extract caused a burst of *NO followed by the increased steady-state level characteristic of saliva containing apple extract. Chlorogenic acid and (+)-catechin, but not ferulic acid, formed o-semiquinone radicals and nitrated polyphenols, suggesting the scavenging of *NO(2) by o-semiquinones. Our results propose that some apple polyphenols not only inhibit nitrosation/nitration but also promote *NO bio-availabilty at the gastric level, a previously unappreciated function.

Antioxidants↗
PubMed2002

Effect of maturity on chlorophyll, tannin, color, and polyphenol oxidase (PPO) activity of sugarcane juice (Saccharum officinarum Var. Yellow Cane).

A study was conducted to determine the effect of sugarcane maturation on the contents of chlorophyll, tannin, and polyphenol oxidase (PPO) activity and on color change of sugarcane juice. The maturation period of the cane studied was between 3 and 10 months after planting. Different parts of the cane, namely, the top, middle, and bottom portions, were analyzed. Results obtained indicated that there were significant (P < 0.01) decreases in total chlorophyll a and b and tannin contents during maturity followed by slower rates of decrease of both parameters at the end of maturity stages. There were no significant differences (P > 0.05) in chlorophyll and tannin contents between the middle and bottom portions. On the other hand, the top portion of the stem had a significantly (P < 0.01) lower concentration of chlorophyll and a significantly (P < 0.01) higher content of tannin. PPO activity of sugarcane juice was determined using chlorogenic acid as a substrate. There was a highly significant difference (P < 0.01) in PPO activity of cane juice during maturity. PPO activity was high at the early development stage, decreased during maturation, and then remained relatively constant at the end of maturity. PPO activity was higher when chlorogenic acid was used as substrate. There were also significant differences (P < 0.01) in juice color (L*, a*, b* values) from different portions at different maturity stages. At the early stages, the color of extracted juice was dark, and then the juice turned to yellowish green during maturity. The decrease in green color or the increase in the yellow color could be associated with the decline in chlorophyll. The overall color change (DeltaE) at maturity indicated that the color of the middle and bottom portions was lower than that of the top portion.

Catechol Oxidase↗
PubMed1998

Short-term ingestion of chlorogenic or caffeic acids decreases zinc but not copper absorption in rats, utilization of stable isotopes and inductively-coupled plasma mass spectrometry technique.

The amount of dietary trace elements absorbed from a meal depends, among other factors, on the quantities of certain minor plant constituents present in the meal. These substances can act as ligands and bind trace elements in the digestive tract in available or unavailable forms for absorption. The present study was designed to investigate the extent to which different polyphenols (PP) may influence Zn and Cu absorption in rats. Different PP of nutritional interest (chlorogenic acid, caffeic acid, catechin and rutin) were studied using meals extrinsically-labelled with stable isotopes 67Zn and 65Cu. Male Wistar rats were fed on a non-labelled semi-synthetic diet containing (mg/kg) 38 Fe, 35 Zn and 7.5 Cu for 8 d. PP were dissolved in dimethyl sulfoxide as the solvent and added to the meal at 1 g/kg during 3 d before isotope administration and until the end of the experiment (a further 3 d). The control group received the dimethyl sulfoxide only. After overnight food deprivation, rats were fed on the labelled test meals (4 g diet +0.1 mg 67Zn and 0.1 mg 65Cu) with 0.5 mg Dy as a faecal marker. Faeces and urine pools were collected for 3 d and analysed for 67Zn and 65Cu isotopic enrichment using the inductively-coupled plasma mass spectrometry technique. Zn absorption was significantly less in rats fed on chlorogenic acid or caffeic acid than in the control group. Catechin ingestion non-significantly inhibited 67Zn absorption. However, the PP studied were without effect on Cu absorption. The study illustrates the effect of metal-binding phenolic compounds on mineral nutrition in the rat, and the possible importance of the effects of different foods rich in these compounds on mineral absorption in man.

Animals↗
PubMed2006

Influence of sample preparation on assay of phenolic acids from eggplant.

Sample preparation is often overlooked and is frequently considered as "a means to an end". This systematic study with a phenolic-enriched substrate, eggplant (Solanum melongena L.), was undertaken to evaluate the substantial variations in the extraction techniques, solvents, and parameters as described in the published literature. Direct comparison of over 10 extraction procedures or conditions was performed to show the importance and influence of sample preparation on the assay of phenolic compounds. Chlorogenic acid (CA) was the most abundant phenolic acid accounting for >75% of the total phenolic acids content extracted from the eggplant sample. Optimum extraction of CA and total phenolics (TP) from Black Bell cultivar of eggplant were obtained when extractions were performed with a mixture of MeOH/H2O at a ratio of 80:20% v/v using a pressurized liquid extractor (PLE) at 100 degrees C. The amount of CA and TP extracted from eggplant by the previously reported procedures using a wrist shaker, rotary shaker, stirring, sonication, or reflux with different extraction solvents (acetone or varying composition of MeOH/H2O solvent mixtures) varied significantly between 5 and 95% as compared to PLE. The predominant phenolic acids in the free phenolic acid fraction of Black Beauty cultivar of eggplant were CA isomers. However, caffeic acid isomers were the major phenolic acids extracted from the base-hydrolyzed fraction. The total amount of caffeic acid extracted from the Italian Neon cultivar was more that twice that of four other eggplant cultivars (Orient Express, Calliope Zebra Stripe, Orient Charm Neon, and Black Beauty).

Caffeic Acids↗
PubMed1996

Protective effects of Acanthopanax senticosus Harms from Hokkaido and its components on gastric ulcer in restrained cold water stressed rats.

The aim of this study is to investigate the pharmacological effect of the stem bark of Acanthopanax senticosus Harms from Hokkaido (Japanese name: Ezoukogi) in place of the root bark as a restorative tonic on the stress-induced gastric ulcer. In the test, the extract of the stem bark of A. senticosus prepared with hot water was dissolved in water and used for the assay of the protective effect of gastric ulcer (erosion) on stressed rats that were restrained on cold water. The result from a single oral administration of the stem bark of A. senticosus-extract (50, 100 and 500 mg/kg, per day) dissolved in 1 ml distilled water did not show any protective effect on gastric ulcer, but the protective effect was observed in a dose-dependent manner from the oral administration of the extract (50, 100 and 500 mg/kg, per day) for 2 weeks. Pre-administration of the stem bark of A. senticosus-extract in a dose of 500 mg/kg showed the most potent inhibition without affecting either body or adrenal glands weights. Among ether, chloroform, n-butanol and aqueous residue extracts from the stem bark of A. senticosus-extract, the n-butanol extract used for oral administration for 2 weeks showed an obvious inhibition of 61.1% on gastric ulcer, compared with the control group which was treated with distilled water in the same way. Chlorogenic acid and syringaresinol di-o-beta-D-glucoside, as the major components of the n-butanol extract, showed a significantly inhibitory effect on gastric ulcer, at 21.4% and 51.3%, respectively. We suggested that the protective effect of the stem bark of A. senticosus on gastric ulcer may be partially due to those of chlorogenic acid and syringaresinol di-o-beta-D-glucoside.

Adrenal Glands↗
PubMed2004

Chemoprotective effect of plant phenolics against anthracycline-induced toxicity on rat cardiomyocytes. Part II. caffeic, chlorogenic and rosmarinic acids.

The chemoprotective effects of caffeic (CA), chlorogenic (CHA) and rosmarinic (RA) acids were tested against the toxicity of doxorubicin (DOX) in neonatal rat cardiomyocytes and the iron-dependent DOX induced lipid peroxidation of heart membranes, mitochondria and microsomes. The protectivity of these acids was compared with dexrazoxan, used as an adjuvant during DOX chemotherapy. The cytoprotective effects were assessed by enzyme (LDH and ASAT) and troponin I leakage, secondly by intracellular ATP content. All hydroxycinnamic acids proved non-cytotoxic, and they stabilized both membranes and the energetic status of cardiomyocytes. After preincubation of cardiomyocytes with the test compounds (100, 200 microm; 1 h) the cardiomyocytes were treated with the toxic agent, DOX (100 microm; 8 h). The test compounds protected cardiomyocytes against DOX induced oxidative stress (RA > CHA > or = CA) on all monitored parameters. Substantial preservation of monolayer integrity of the cardiomyocytes by test compounds was also found microscopically. All the acids were more effective in the assays used than dexrazoxan. RA showed the most effective cytoprotectivity. All the acids significantly reduced the iron-dependent DOX induced lipid peroxidation of heart membranes, although of the test compounds, CHA was found to be the most effective (IC(50) = 8.04 +/- 0.74/6.87 +/- 0.52 micro m for microsomes/mitochondria).

Animals↗
PubMed2001

[Determination of polyphenols in tobacco by solid phase extraction and high performance liquid chromatography].

A high performance liquid chromatographic (HPLC) method for the determination of polyphenols in tobacco was studied. Polyphenols can be extracted from tobacco sample by refluxing with 80% (volume fraction) methanol, then subjected to degrease by solid phase extraction with Sep-Pak-C18 column. Chlorogenic acid, rutin, scopoletin, caffeic acid, scopolin and other polyphenols can be separated on a Nova-Pak-C18 column (3.9 mm i.d. x 150 mm) gradiently eluted with methanol and 0.05 mol.L-1 potassium dihydrogen phosphate buffer solution as mobile phase at a flow-rate of 0.5 mL.min-1. Polyphenols were determined at the maximum wavelength of each polyphenol, for chlorogenic acid 326.1 nm, rutin 354.8 nm, scopoletin 344.0 nm, caffeic acid 323.7 nm and scopolin 365.2 nm by photodiode array detector. The main polyphenols in tobacco can be identified with UV spectroscopy. The recoveries of tobacco polyphenols were 94%-105%, and the relative standard deviations were 1.28%-1.49%. This method can be applied to the determination of polyphenols in tobacco with satisfactory results.

Chromatography, High Pressure Liquid↗
PubMed2004

Applied environmental stresses to enhance the levels of polyphenolics in leaves of hawthorn plants.

In this investigation, two species of Crataegus (hawthorn) were chosen because their polyphenolic constituents have recently received greater attention for the treatment of patients with severe heart disease. One-year-old plants of hawthorn (Crataegus laevigata and C. monogyna) were subjected to water-deficit (continuous water deprivation), cold (4 degrees C), flooding (immersion of roots of plants in water) or herbivory (leaf removal) stress treatments (each of 10 days duration) in order to assess their effects on levels of polyphenolics, namely (-)-epicatechin, catechin, chlorogenic acid, vitexin, vitexin-2"-O-rhamnoside, acetylvitexin-2"-O-rhamnoside, hyperoside, quercetin, and rutin in the leaves. The working hypothesis followed is that one or more of these stress treatment will elicit increases in the levels of these polyphenolics. Cold stress causes increases in levels of vitexin-2"-O-rhamnoside, acetylvitexin-2"-O-rhamnoside, hyperoside, and quercetin in both Crataegus species. Water-deficit stress increased the productivity of chlorogenic acid, catechin, and (-)-epicatechin in both hawthorn species. Flooding and herbivory caused no net increases, and in some cases, decreases in levels of polyphenolics. These studies indicate that either water-deficit stress or cold stress treatments, or a combination of the two, can be used to enhance the levels of desired polyphenolics in the leaves of these two hawthorn species in a photobioreactor system. These results may have significance for hawthorn in adapting to water-deficit or cold stress and are important considerations for the use of hawthorn in the treatment of heart disease in humans.

Journal Article↗