Daylily (Hemerocallis fulva Linn.) flowers improve sleep quality in human and reduce nitric oxide and interleukin-6 production in macrophages.

The flowers of daylily (Hemerocallis fulva Linn.) have been used as vegetable and medicinal herb for thousands of years in Taiwan and eastern Asia. Daylily flowers have been demonstrated to exert several biomedical properties. In this study, we provided the evidences show that daylily flowers exert anti-inflammatory activity in vitro and improved the sleep quality in vivo. We demonstrated that adult volunteers received water extract of daylily flowers improved sleep quality, sleep efficiency and daytime functioning, while sleep latency was reduced, compared to the adult volunteers received water. In addition, we demonstrated that aqueous and ethanol extracts of daylily flowers inhibited nitric oxide and interleukin-6 production in lipopolysaccharide-activated macrophages. Furthermore, the quantitative high performance liquid chromatography-based analysis showed the rutin content of the aqueous extract, ethanolic extract, ethyl acetate fractions of ethanolic extract, and water fractions of ethanolic extract were 7.27, 23.30, 14.71, and 57.43 ppm, respectively. These results indicate that daylily flowers have the potential to be a nutraceutical for improving inflammatory-related diseases and sleep quality in the future.

Freeze-dried powder of daylily bud improves bromocriptine-induced lactation disorder in rats via JAK2/STAT5 pathway.

ETHNOPHARMACOLOGICAL RELEVANCE: Milk deficiency is a prevalent problem in the world. Daylily (Hemerocallis citrina Borani), called the Chinese mother flower, is a traditional vegetable and is believed to possess a galactagogue effect in China. Flavonoids and phenols are considered as the active ingredients of daylily to promote lactation and improve depression. AIM OF THE STUDY: The aim of this study was to investigate the prolactin effects of freeze-dried powder of flower buds of H. citrina Baroni in rat and its action mechanisms. MATERIALS AND METHODS: The chemical constituents of flower buds of H. citrina Baroni treated by different drying techniques were analyzed by ultrahigh pressure liquid chromatography-mass spectrometry. Sprague-Dawley (SD) rat model induced by bromocriptine was used to evaluate the effect of freeze-dried powder of daylily buds on promoting lactation. Network pharmacology method, ELISA, qPCR, and Western blot were used to clarify the action mechanisms. RESULTS: We detected 657 compounds in daylily buds. The relative contents of total flavonoids and phenols in freeze-dried samples were higher than those in dried ones. Bromocriptine, as a dopamine receptor agonist, can significantly inhibit prolactin in rats. Daylily buds can restore the levels of prolactin, progesterone and estradiol depressed by bromocriptine, effectively improve the milk production of the rat, and promote the repair of rat mammary gland tissue. We analyzed the relationship between the chemical components of daylily buds and the genes related to lactation with network pharmacology method, revealing that flavonoids and phenols may be the active components that promoted milk production via JAK2/STAT5 pathway, which was confirmed by the results of qPCR and Western blot. Daylily buds can increase the mRNA expression of PRLR, CSN2, LALBA and FASN and the protein expression of PRLR, JAK2 and STAT5. CONCLUSION: Daylily buds can improve the insufficient lactation of rats induced by bromocriptine through PRLR/JAK2/STAT5 pathway, and the freeze-dried processing method may better retain the active components of flavonoids and phenols that promote milk in daylily.

An Investigation of the Anti-Depressive Properties of Phenylpropanoids and Flavonoids in Hemerocallis citrina Baroni.

The World Health Organization predicts that over the next several years, depression will become the most important mental health issue globally. Growing evidence shows that the flower buds of Hemerocallis citrina Baroni (H. citrina) possess antidepressant properties. In the search for new anti-depression drugs, a total of 15 phenylpropanoids and 22 flavonoids were isolated and identified based on spectral data (1D and 2D NMR, HR-ESI-MS, UV) from H. citrina. Among them, compound 8 was a novel compound, while compounds 1-4, 6, 9, 10, 15, 17, 24-26, 28, and 37 were isolated for the first time from Hemerocallis genus. To study the antidepressant activity of phenylpropanoids and flavonoids fractions from H. citrina, macroporous resin was used to enrich them under the guidance of UV characteristics. UHPLC-MS/MS was applied to identify the constituents of the enriched fractions. According to behavioral tests and biochemical analyses, it showed that phenylpropanoid and flavonoid fractions from H. citrina can improve the depressive-like mental state of chronic unpredictable mild stress (CUMS) rats. This might be accomplished by controlling the amounts of the inflammatory proteins IL-6, IL-1ß, and TNF-α in the hippocampus as well as corticosterone in the serum. Thus, the monomer compounds were tested for their anti-neuroinflammatory activity and their structure-activity relationship was discussed in further detail.

Study on Extraction and Antioxidant Activity of Flavonoids from Hemerocallis fulva (Daylily) Leaves.

Hemerocallis fulva is a medical and edible plant. In this study, we optimized the ultrasound-assisted extraction (UAE) process of extracting flavonoids from Hemerocallis fulva leaves by single-factor experiments and response surface methodology (RSM). The optimum extraction conditions generating the maximal total flavonoids content was as follows: 70.6% ethanol concentration; 43.9:1 mL/g solvent to sample ratio; 61.7 °C extraction temperature. Under the optimized extraction conditions, the total flavonoid content (TFC) in eight Hemerocallis fulva varieties were determined, and H. fulva (L.) L. var. kwanso Regel had the highest TFC. The cytotoxicity of the extract was studied using the Cell Counting Kit-8 (CCK-8 assay). When the concentration was less than 1.25 mg/mL, the extract had no significant cytotoxicity to HaCaT cells. The antioxidant activity was measured via chemical antioxidant activity methods in vitro and via cellular antioxidant activity methods. The results indicated that the extract had a strong ABTS and •OH radical scavenging activity. Additionally, the extract had an excellent protective effect against H2O2-induced oxidative damage at a concentration of 1.25 mg/mL, which could effectively reduce the level of ROS to 106.681 ± 9.733% (p < 0.001), compared with the 163.995 ± 6.308% of the H2O2 group. We identified five flavonoids in the extracts using high-performance liquid chromatography (HPLC). Infrared spectroscopy indicated that the extract contained the structure of flavonoids. The results showed that the extract of Hemerocallis fulva leaves had excellent biocompatibility and antioxidant activity, and could be used as a cheap and potential source of antioxidants in the food, cosmetics, and medicine industries.

Exploring the Extraction Methods of Phenolic Compounds in Daylily (Hemerocallis citrina Baroni) and Its Antioxidant Activity.

Daylily is a valuable plant resource with various health benefits. Its main bioactive components are phenolic compounds. In this work, four extraction methods, ultrasonic-assisted water extraction (UW), ultrasonic-assisted ethanol extraction (UE), enzymatic-assisted water extraction (EW), and enzymatic-assisted ethanol extraction (EE), were applied to extract phenolic compounds from daylily. Among the four extracts, the UE extract exhibited the highest total phenolic content (130.05 mg/100 g DW) and the best antioxidant activity. For the UE extract, the DPPH value was 7.75 mg Trolox/g DW, the FRAP value was 14.54 mg Trolox/g DW, and the ABTS value was 15.37 mg Trolox/g DW. A total of 26 phenolic compounds were identified from the four extracts, and the UE extract exhibited a higher abundance range of phenolic compounds than the other three extracts. After multivariate statistical analysis, six differential compounds were selected and quantified, and the UE extract exhibited the highest contents of all six differential compounds. The results provided theoretical support for the extraction of phenolic compounds from daylily and the application of daylily as a functional food.

Hemecitones A and B: two phenanthrenes with cytotoxicity from Hemerocallis fulva (L.) L.

Two new phenanthrenes, Hemecitones A and B, were isolated from Hemerocallis fulva (L.) L. Their structures were determined by UV, IR, HR-ESI-MS, 1D and 2D NMR analysis. The in vitro cytotoxic activities of compounds 1 and 2 were studied against breast carcinoma MDA-MB-231, hepatocellular carcinoma HepG2 and lung carcinoma A549 cell lines. And compounds 1 and 2 exhibited anti-proliferative effects against these least one of the three types of cell lines with IC50 ranging from 12.57 ± 2.34 to 31.22 ± 1.36 µM.[Formula: see text].

Optimization of ultrasonic-assisted extraction of polysaccharides from Hemerocallis citrina and the antioxidant activity study.

The present study discussed the optimization of the ultrasonic-assisted extraction of polysaccharides from daylily polysaccharides (DPs). The extracted crude polysaccharides were further separated and purified, and the antioxidant activities including 1,1-diphenyl-2-111 picrylhydrazyl (DPPH) radical scavenging, 2,2'-azinobis-(3-ethylbenzthiazoline-6-sulphonate) (ABTS) radical scavenging, hydroxyl radical scavenging, and ferric-reducing antioxidant power (FRAP) activities of the obtained fractions were also evaluated. The results showed that the optimal ultrasonic-assisted extraction parameters with DPs yield of 15.25 ± 1.13% were water to powder ratio of 25 ml/g, extraction power of 694 W, extraction temperature of 71°C, extraction time of 38 min, and three times extraction. By DEAE Sepharose Fast Flow column, four water-soluble polysaccharide fractions (DP-1, DP-2, DP-3, and DP-4) were successfully obtained. Monosaccharide component analysis showed that the four obtained fractions were all hetero-polysaccharides that mainly contained rhamnose, arabinose, fructose, galactose, glucose, galacturonic acid, and glucuronic acid in different molar ratios. All the four DP fractions did show obvious antioxidant activities in vitro, and the DP-3 component had relatively high ABTS free radical scavenging activity. Overall, our research showed that DPs could provide cheap raw materials for the development of natural antioxidants in medicines, functional foods, and even cosmetics. PRACTICAL APPLICATION: This article deals with the optimization of the ultrasonic-assisted extraction of polysaccharides from daylily and its antioxidant activities. The results showed that the optimal ultrasonic-assisted extraction yield of DPs was 15.25 ± 1.13%. By DEAE Sepharose Fast Flow column, four water-soluble polysaccharide fractions were successfully obtained, and all the four DP fractions did show obvious antioxidant activities in vitro. Daylily polysaccharides could provide cheap raw materials for the development of natural antioxidants in medicines, functional foods, and even cosmetics.

Systematic identification metabolites of Hemerocallis citrina Borani by high-performance liquid chromatography/quadrupole-time-of-flight mass spectrometry combined with a screening method.

Hemerocallis citrina Borani is an important crop and its flower buds are widely consumed in East Asian areas as a vegetable, as well as in traditional Chinese medicine, due to its health-promoting properties. Metabolites present in plant-derived foods or medicines are in part responsible for their desirable flavor profiles and health benefits. Nevertheless, detailed information about these compounds in H. citrina is scarce. Therefore, this study aimed to investigate the metabolites by high-performance liquid chromatography/quadrupole time-of-flight mass spectrometry (HPLC-Q-TOF-MS). In this study, a total of 144 compounds, including 14 amides, 25 polyphenols, 44 flavonols, 35 anthraquinones, 15 naphthols, and 11 other components, were detected by the established screening method and were identified by their precise m/z values, characteristic tandem mass spectrometry (MS/MS) data and fragmentation pathways of references, 111 of which were reported in this plant for the first time. The distribution of identified ingredients in different parts of H. citrina was determined. Interestingly, colchicine, which had been reported as a toxic compound in the fresh flower buds in previous studies and various news reports, was not found. This work marks the first comprehensive study of metabolites from commercial flower buds and different parts of H. citrina.

Ethyl Acetate Fraction of Hemerocallis citrina Baroni Decreases Tert-butyl Hydroperoxide-Induced Oxidative Stress Damage in BRL-3A Cells.

The main purposes of this study were to screen the antioxidant activities of various fractions of Hemerocallis citrina Baroni and test their hepatoprotective effects in vitro. Antioxidant assays (2,2-diphenyl-1-picrylhydrazyl (DPPH), 2,2'-azino-bis(3-ethylbenzothiazoline-6-sulfonic acid) (ABTS), and reducing power experiments) and tert-butyl hydroperoxide- (t-BHP-) induced BRL-3A oxidative damage experiments were performed in vitro. The H. citrina ethyl acetate fraction (HCEA) was determined to have strong antioxidant activity because of its high flavonoid and polyphenol content. Ultraperformance liquid chromatography- (UPLC-) photodiode array (PDA)/mass spectrometry (MS) analysis showed that the main components of the HCEA were flavonoids and caffeic acid derivatives. A total of 17 compounds were identified. HCEA also effectively protected the liver against t-BHP-induced oxidative stress injury and significantly reduced reactive oxygen (ROS) accumulation. Moreover, HCEA significantly reduced levels of alanine aminotransferase (ALT), aspartate transaminase (AST), and lactate dehydrogenase (LDH). Further studies have shown that HCEA inhibits t-BHP-induced apoptosis by increasing B-cell lymphoma-2 (BCL-2) activity and decreasing caspase-3 and caspase-9 activity. Moreover, HCEA enhanced the activity of antioxidant enzymes superoxide dismutase (SOD) and catalase (CAT), as well as the total antioxidant capacity (T-AOC), and increased the antioxidant level of glutathione (GSH) in BRL-3A cells. HCEA increased the antioxidant capacity of cells by increasing the gene expression of AMP-activated protein kinase (AMPK), extracellular signal-regulated kinase (ERK), P38, nuclear factor, erythroid 2 like 2 (Nrf2), SOD, glutamate-cysteine ligase catalytic subunit (GCLC), glutamate-cysteine ligase modifier subunit (GCLM), and heme oxygenase 1 (HO-1), which are associated with antioxidant pathways to protect against oxidative stress. In conclusion, HCEA protected BRL-3A cells against t-BHP-induced oxidative stress damage via antioxidant and antiapoptosis pathways. Therefore, H. citrina Baroni may serve as a potential hepatoprotective drug.

Aqueous and Ethanol Extracts of Daylily Flower (Hemerocallis fulva L.) Protect HUVE Cells Against High Glucose.

The content of several phenolic acids and flavonoids in aqueous extract (AE) and ethanol extract (EE) of daylily flower (Hemerocallis fulva L.) was analyzed. The effects of AE or EE at 0.5%, 1%, or 2% in HUVE cells against high glucose-induced cell death, oxidative, and inflammatory damage were examined. Results showed that seven phenolic acids and seven flavonoids could be detected in AE or EE, in the range of 29 to 205 and 41 to 273 mg/100 g, respectively. Compared with the control groups, high glucose raised the activity of caspase-3 and caspase-8; suppressed Bcl-2 mRNA expression and increased Bax mRNA expression; and induced HUVE cells apoptosis. The pretreatments from AE or EE at 1% or 2% reduced caspase-3 activity and Bax mRNA expression, and enhanced cell viability. High glucose decreased glutathione content; stimulated the production of reactive oxygen species, interleukin-6, tumor necrosis factor-alpha, and prostaglandin E2 ; raised the activity of cyclooxygenase-2 and nuclear factor kappa B p50/65 binding; and reduced the activity of glutathione peroxidase, glutathione reductase, and catalase in HUVE cells. AE pretreatments at 1% and 2% reversed these changes. These novel findings suggested that daylily flower was rich in phytochemicals, and could be viewed as a potent functional food against diabetes.

Eight new γ-lactam alkaloids from the roots of the Hemerocallis minor Mill.

Eight new γ-lactam alkaloids, hemerominors A-H (1-8), including two pair of epimers (1-4), together with six known compounds (9-14) were isolated from the roots of Hemerocallis minor Mill. The structures of 1-8 were established on the basis of extensive NMR studies and HR-MS measurements as well as comparison with literature data. The absolute configurations of 1-8 were determined by CD spectral analysis and modified Mosher's method. All of compounds were evaluated for their inhibitory effects against LPS-induced NO production in RAW264.7 macrophages. Among them, compound 13 exhibited moderate inhibitory activity against NO production and with IC50 value of 18.0 µM.

Effects of phenolic constituents of daylily flowers on corticosterone- and glutamate-treated PC12 cells.

BACKGROUND: Daylily flowers, the flower and bud parts of Hemerocallis citrina or H. fulva, are well known as Wang-You-Cao in Chinese, meaning forget-one's sadness plant. However, the major types of active constituents responsible for the neurological effects remain unclear. This study was to examine the protective effects of hydroalcoholic extract and fractions and to identify the active fractions. METHODS: The extract of daylily flowers was separated with AB-8 resin into different fractions containing non-phenolic compounds, phenolic acid derivatives and flavonoids as determined using UPLC-DAD chromatograms. The neuroprotective activity was measured by evaluating the cell viability and lactate dehydrogenase release using PC12 cell damage models induced by corticosterone and glutamate. The neurological mechanisms were explored by determining their effect on the levels of dopamine (DA), 5-hydroxy tryptamine (5-HT), γ-aminobutyric acid (GABA), noradrenaline (NE) and acetylcholine (ACh) in the cell culture medium measured using an LC-MS/MS method. RESULTS: Pretreatment of PC12 cells with the extract and phenolic fractions of daylily flowers at concentrations ranging from 0.63 to 5 mg raw material/mL significantly reversed corticosterone- and glutamate-induced neurotoxicity in a dose-dependent manner. The fractions containing phenolic acid derivatives (0.59% w/w in the flowers) and/or flavonoids (0.60% w/w) exerted similar dose-dependent neuroprotective effect whereas the fractions with non-phenolic compounds exhibited no activity. The presence of phenolic acid derivatives in the corticosterone- and glutamate-treated PC12 cells elevated the DA level in the cell culture medium whereas flavonoids resulted in increased ACH and 5-HT levels. CONCLUSION: Phenolic acid derivatives and flavonoids were likely the active constituents of daylily flowers and they conferred a similar extent of neuroprotection, but affected the release of neurotransmitters in a different manner.

γ-Lactam alkaloids from the flower buds of daylily.

Four new alkaloids, hemerocallisamines IV-VII, were isolated from the methanol extract of flower buds of daylily. The chemical structures of the new compounds were elucidated on the basis of chemical and physicochemical evidence. The absolute stereochemistry of the hemerocallisamines IV-VI was elucidated by the application of the modified Mosher's method, HPLC analysis, and optical rotation. In the present study, the isolated alkaloids significantly inhibited the aggregation of Aß42 in vitro. This is the first report about bioactive alkaloids with a γ-lactam ring from daylily. In addition, isolated nucleosides showed accelerative effects on neurite outgrowth under the non-fasting condition.

An evaluation of novel biological activity in a crude extract from Hemerocallis fulva L. var. sempervirens M. Hotta.

Hemerocallis fulva L. var. sempervirens M. Hotta (kwanso) represents an exceptional resource for identifying and developing new phytomedicines for the treatment and prevention of disease. The aim of this study was to conduct a detailed investigation of the biological activities of kwanso. Our study resulted in four major findings. First, kwanso scavenges hydroxyl radicals generated by H(2)O(2)/UV light system in vitro in a dose-dependent manner. Second, hepatic glutathione levels were significantly increased when kwanso was orally administered to mice. Third, the oral administration of kwanso to mice showed a tendency to suppress hepatic injury induced by acetaminophen. Finally, kwanso slightly inhibited cytochrome P450 3A activity. These results provide useful evidence in support of the development of kwanso as a candidate raw material for the treatment and prevention of disease.

Antioxidative caffeoylquinic acids and flavonoids from Hemerocallis fulva flowers.

Tumor necrosis factor-α (TNF-α)-induced reactive oxygen species (ROS) production in HepG2 was used to screen hepatocyte protective compounds from the flowers of Hemerocallis fulva. Three new polyphenols, n-butyl 4-trans-O-caffeoylquinate (1), kaempferol 3-O-{α-L-rhamnopyranosyl(1→6)[α-L-rhamnopyranosyl(1→2)]}-ß-D-galactopyranoside (2), and chrysoeriol 7-O-[ß-D-glucuronopyranosyl(1→2)(2-O-trans-feruloyl)-ß-D-glucuronopyranoside (3), together with four caffeoylquinic acid derivatives (4-7), eight known flavones (8-15), one naphthalene glycoside, stelladerol (16), one tryptophan derivative (17), adenosine (18), and guanosine (19) were isolated from the bioactive fractions of the aqueous ethanol extract of H. fulva flowers. The structures of isolated compounds were characterized by means of spectroscopic data. Compounds 1-3 were described as first isolated natural products. Among the above-mentioned compounds, the caffeoylquinic acid derivatives are the major components with potent free radical scavenging activity in HepG2 cells and are for the first time isolated from H. fulva flowers. A convenient ultraperformance liquid chromatography (UPLC) method was also developed to simultaneously separate and identify caffeoylquinic acids and flavonoids promptly.

Enhancement of lipolytic responsiveness of adipocytes by novel plant extract in rat.

Subcutaneous adipocytes accumulate excess energy as triglycerides, but lipolytic response is less sensitive to catecholamines than visceral adipocytes. Obesity also induces catecholamine resistance of adipocytes. We have searched for crude drugs that could enhance the lipolytic response to noradrenalin. In this study, the lipolysis-promoting activities and action mechanisms of a novel plant extract from Hemerocallis fulva (HE) were investigated in isolated adipocytes from rat subcutaneous fat. HE exhibited no lipolysis-promoting activity alone but markedly promoted lipolysis when combined with noradrenaline; however, this synergistic activity was accompanied by no increase of intracellular cAMP production. This activity of HE was also observed when combined with cAMP analogue and was further enhanced by phosphodiesterase inhibitor. PKA inhibitor could reduce these activities of HE. These results indicate that HE is a novel lipolysis-promoting material that can sensitize the lipolytic response of adipocytes to catecholamine and suggest that HE can amplify the intra-cellular signaling pathway related to PKA or modify the other mechanism-regulating lipase activity. This characteristic material could contribute to improvement of adipose mobility in obesity-related disorder or in subcutaneous adiposity and to suppression of body fat accumulation.

In vitro and vivo antioxidant activities of daylily flowers and the involvement of phenolic compounds.

Daylily (Hemerocallis fulva Linn.) flowers were hot air-dried and freeze-dried after harvest. Antioxidant properties of water and ethanol extracts prepared from these dried flowers were evaluated in terms of total antioxidant activity, reducing capacity, and metal chelating activity. Extracts from daylily flowers exhibited strong antioxidant activity. Ethanol was more efficiency to extract antioxidants than water, and freeze-drying preserved higher activities than air-drying. Rutin, (+)-catechin, and gallic acid were identified in the extracts by HPLC, and were highly related to the antioxidant activities. The antioxidant activity was further evaluated by feeding mice with ethanol extract from freeze-dried daylily flowers for 60 days. The results demonstrated that the extract at dosage of 40-225 mg/100 g significantly increased the activity of SOD (superoxide dismutase) and reduced the lipid peroxidation in both blood and liver of rat.

Lipid peroxidation inhibitory compounds from daylily (Hemerocallis fulva) leaves.

Daylilies (Hemerocallis spp.) have been used as food and in traditional medicine for thousands of years in eastern Asia. The leaves of the plant are used in the treatment of inflammation and jaundice. In studies of the aqueous methanol extracts of fresh Hemerocallis fulva leaves, 1',2',3',4'-tetrahydro-5'-deoxy-pinnatanine (1), pinnatanine (2), roseoside (3), phlomuroside (4), lariciresinol (5), adenosine (6), quercetin 3-O-beta-D-glucoside (7), quercetin 3,7-O-beta-D-diglucopyranoside (8), quercetin 3-O-alpha-L-rhamnopyransol-(1-->6)-beta-D-glucopyranosol-7-O-beta-D-glucopyranoside (9), isorhamnetin-3-O-beta-D-6'-acetylglucopyranoside (10) and isorhamnetin-3-O-beta-D-6'-acetylgalactopyranoside (11) were isolated. All of these compounds were tested for their in vitro lipid peroxidation inhibitory activities. Compounds 3-5 and 7-11 were found to possess strong antioxidant properties, inhibiting lipid oxidation by 86.4, 72.7, 90.1, 79.7, 82.4, 89.3, 82.2, and 93.2%, respectively at 50 microg/mL. Compound 1 is novel and compounds 3-6 and 8-11 described here in are isolated for the first time from daylily leaves.

Inhibition of human tumor cell proliferation by novel anthraquinones from daylilies.

Daylilies (Hemerocallis) are used medicinally in eastern Asia and extracts of the plant had been shown to inhibit cell proliferation and induce cancer cells to undergo differentiation. In our studies of the constituents of Hemerocallis fulva var. 'Kwanzo' roots, we isolated a series of new [kwanzoquinones A (1), B (2), C (4), D (5), E (6), F (7), G (9)] and known [2-hydroxychrysophanol (3) and rhein (8)] anthraquinones. These compounds were tested in order to determine their potential roles as cancer cell growth inhibitors. Kwanzoquinones A-C and E, kwanzoquinone A and B monoacetates (1a and 2a), 2-hydroxychrysophanol, and rhein inhibited the proliferation of human breast, CNS, colon, and lung cancer cells with GI50 values between 1.8 to 21.1 microg/mL. However, upon exposure of the cancer cells to the GI50 concentrations of the bioactive anthraquinones, most of the cancer cell lines exhibited higher than anticipated levels of cell viability. Co-incubation of the anthraquinones with vitamins C and E increased the viability of breast cancer cells. In contrast, vitamins C and E potentiated the cytotoxic effects of the anthraquinones against the colon cancer cells. None of the anthraquinones inhibited the activity of topoisomerase.