Publications by authors named "Yanping Zou"

13 Publications

  • Page 1 of 1

Increased M2 Isoform of Pyruvate Kinase in Fibroblasts Contributes to the Growth, Aggressiveness, and Osteoclastogenesis of Odontogenic Keratocysts.

Am J Pathol 2021 05 26;191(5):857-871. Epub 2021 Feb 26.

State Key Laboratory Breeding Base of Basic Science of Stomatology (Hubei-MOST) and Key Laboratory of Oral Biomedicine Ministry of Education, School and Hospital of Stomatology, Wuhan University, Wuhan, China; Department of Oral and Maxillofacial Surgery, School and Hospital of Stomatology, Wuhan University, Wuhan, China. Electronic address:

To investigate the role of glycolysis and the M2 isoform of pyruvate kinase (PKM2) in odontogenic keratocysts (OKCs), the glycolytic flux of primary odontogenic keratocyst fibroblasts (OKC-Fs) and normal oral mucosa fibroblasts (OM-Fs) was determined by glucose uptake, lactate production, and cell proliferation assays. Wound healing assay and Matrigel-coated chamber system were used to investigate the effects of PKM2 on migration and invasion capacities of OKC-Fs. Co-culture of OKC-Fs with osteoclast precursors (RAW264.7 cells) was used to clarify the role of glycolysis in the osteoclastogenic effects of OKC-Fs. In addition, hypoxia-inducible factor 1α and some key enzymes related to glycolysis, including PKM2, 6-phosphofructo-2-kinase/fructose-2, 6-biphosphatase 3, hexokinase 2, and lactate dehydrogenase A, were detected to assess the activation of glycolysis in OKC stroma by immunohistochemistry. Results showed that the glucose uptake and lactate production were significantly higher in OKC-Fs than OM-Fs. PKM2 was elevated in OKC-Fs compared with that in OM-Fs. PKM2 significantly regulated glycolysis, proliferation, migration, invasion, and osteoclastogenic effects of OKC-Fs. Additionally hypoxia-inducible factor 1α, 6-phosphofructo-2-kinase/fructose-2, 6-biphosphatase 3, hexokinase 2, and lactate dehydrogenase A were markedly overexpressed in OKC stroma, and correlated with PKM2. Moreover, the expression of PKM2 was regulated by oxygen concentration in vitro. In sum, PKM2-mediated glycolysis regulated the growth, aggressiveness, and osteoclastogenesis of OKC.
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http://dx.doi.org/10.1016/j.ajpath.2021.02.010DOI Listing
May 2021

Pyruvate Kinase M2 Mediates Glycolysis in the Lymphatic Endothelial Cells and Promotes the Progression of Lymphatic Malformations.

Am J Pathol 2021 01 29;191(1):204-215. Epub 2020 Oct 29.

State Key Laboratory Breeding Base of Basic Science of Stomatology (HUbei-MOST) & Key Laboratory of Oral Biomedicine, Ministry of Education, School & Hospital of Stomatology, Wuhan University, Wuhan, China; Department of Oral & Maxillofacial Surgery, School & Hospital of Stomatology, Wuhan University, Wuhan, China. Electronic address:

Metabolism plays a pivotal role in the formation of the lymphatic vasculature. Pyruvate kinase M2 (PKM2) is typically a metabolic marker of proliferating cells and maintains the growth of vascular endothelial cells. In this study, the potential status of PKM2 in lymphatic endothelial cells and the pathogenesis of lymphatic malformations (LMs) was investigated. The glycolysis index, including glucose uptake, ATP, and lactate production, stayed at a relatively high level in human dermal lymphatic endothelial cells (HDLECs) compared with human umbilical vein endothelial cells, whereas the inhibition of PKM2 by shikonin or PKM2 knockdown significantly suppressed glycolysis, migration, tubular formation, and invasion of HDLECs. Moreover, compared with lymphatic vessels in healthy skin, lymphatic vessels of LMs expressed PKM2 highly, and this expression correlated with infection of LMs. Meanwhile, the overexpression of PKM2 in HDLECs strengthened the proliferation, migration, tubular formation, and invasion of HDLECs. The findings from further experiments in a rat LM model support that targeting PKM2 by shikonin significantly impedes the progression of LMs, even in an infected LM rat model. Taken together, these results indicate that PKM2 plays a pivotal role in the activation of LECs and promotes the progression of LMs, whereas the inhibition of PKM2 can effectively suppress the pathogenesis of LM lesions in the rat model.
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http://dx.doi.org/10.1016/j.ajpath.2020.10.003DOI Listing
January 2021

The YAP signaling pathway promotes the progression of lymphatic malformations through the activation of lymphatic endothelial cells.

Pediatr Res 2021 01 12;89(1):110-117. Epub 2020 Apr 12.

The State Key Laboratory Breeding Base of Basic Science of Stomatology (Hubei-MOST) and Key Laboratory of Oral Biomedicine Ministry of Education, School and Hospital of Stomatology, Wuhan University, Wuhan, China.

Background: To investigate whether the YAP/TAZ (Yes-associated protein/transcriptional coactivator with PDZ binding motif) pathway contributes to the pathogenesis of lymphatic malformations (LMs).

Methods: YAP, TAZ, CTGF (connective tissue growth factor), and Ki-67 were detected in LMs by immunohistochemistry. The colocalization of YAP and Ki-67 was analyzed by double immunofluorescence. Pearson's correlation and cluster analyses were performed to analyze the relationships between these proteins. Human dermal lymphatic endothelial cells (HDLECs) were used for mechanistic investigation. Rat models of LMs were established to investigate the role of the YAP pathway in LM development.

Results: Compared with those in normal skin, the expression levels of YAP, TAZ, CTGF, and Ki-67 were significantly upregulated in lymphatic endothelial cells (LECs) of LMs. Interestingly, YAP and CTGF presented much higher expression levels in infected LMs. In experiments in vitro, lipopolysaccharide (LPS) enhanced the expression of YAP in a concentration- and time-dependent manner via the increased phosphorylation of Erk1/2 (extracellular signal-regulated kinase 1/2). Moreover, the proliferation, invasion, and tubule formation of HDLECs increased significantly in accordance with the activation of the YAP signaling pathway. Furthermore, LM rat models validated that LPS facilitated the development of LMs, which was dependent on the activation of YAP.

Conclusions: The data reveal that activation of the YAP signaling pathway in LECs may play a crucial role in the progression of LMs.

Impact: Compared with that in normal skin, the YAP signaling pathway was activated in LECs of LMs. Inhibiting the YAP signaling pathway attenuated the proliferation, invasion, and tubule formation of HDLECs. Additionally, the activation of the YAP signaling pathway could promote LM development in a rat model. Activation of the YAP signaling pathway in LECs may play a crucial role in the progression of LMs. The YAP signaling pathway was activated in LMs. Inhibition of the YAP signaling pathway could promote regression of the lesions.
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http://dx.doi.org/10.1038/s41390-020-0863-0DOI Listing
January 2021

Hydrostatin-SN10 Ameliorates Pancreatitis-Induced Lung Injury by Affecting IL-6-Induced JAK2/STAT3-Associated Inflammation and Oxidative Stress.

Oxid Med Cell Longev 2019 18;2019:9659757. Epub 2019 Nov 18.

Department of Gastroenterology, The First Affiliated Hospital of Jinzhou Medical University, Jinzhou 121001, China.

Hydrostatin-SN1 (peptide sequence, DEQHLETELHTLTSVLTANGFQ), a kind of peptides extracted from snake venom, has been reported to have anti-inflammatory effect, but its truncated mutant hydrostatin-SN10 (peptide sequence, DEQHLETELH) on pancreatitis-induced acute lung injury has not been well documented. Interleukin- (IL-) 6-induced Janus Kinase 2/Signal Transducer and Activator of Transcription 3 (JAK2/STAT3) pathway is involved with inflammatory and oxidative stress activities and may be associated with the pathogenesis of lung injury, and related molecules were measured. Taurocholate-induced pancreatitis associated with acute lung injury was established and treated with hydrostatin-SN10. Pancreatitis was confirmed by measuring the serum levels of amylase, lipase, and trypsinogen and urinary amylase. Lung injury was determined by histologically assessing acinar cell changes. The related molecules of IL-6-induced JAK2/STAT3-associated inflammation and oxidative stress were quantitated by real time-PCR, Western blot, and/or immunochemical assay. Hydrostatin-SN10 reduced the levels of serum amylase, lipase, and trypsinogen and urinary amylase when compared with the model group ( < 0.05). Hydrostatin-SN10 significantly inhibited the IL-6-stimulated JAK2/STAT3 pathway and reduced the number of apoptotic cells via the downregulation of caspase 3 and BAX (proapoptotic) and upregulation of Bcl2 (antiapoptotic) ( < 0.05). IL-6 induced the increase in the levels of JAK2 and STAT3, which was reversed by hydrostatin-SN10 treatment ( < 0.05). In addition, hydrostatin-SN10 reduced the expression of IL-6 and TNF- (tumor necrosis factor-) and increased the level of IL-10 ( < 0.05). On the other hand, hydrostatin-SN10 treatment increased the levels of superoxide dismutase (SOD) and reduced glutathione (GSH) and the levels of malondialdehyde (MDA) and alanine aminotransferase (ALT) ( < 0.05). These results suggest that hydrostatin-SN10 may inhibit pancreatitis-induced acute lung injury by affecting IL-6-mediated JAK2/STAT3 pathway-associated inflammation and oxidative stress.
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http://dx.doi.org/10.1155/2019/9659757DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6885838PMC
May 2020

Clonal diversity of Ureaplasma species and its relationship with oligozoospermia and semen quality in Chinese infertile males.

Eur J Clin Microbiol Infect Dis 2018 Oct 26;37(10):1957-1963. Epub 2018 Jul 26.

Department of Clinical Laboratory, Sir Run Run Shaw Hospital, Zhejiang University School of Medicine, Hangzhou, 310016, Zhejiang, People's Republic of China.

Whether Ureaplasma spp. are a causative agent of male infertility remains controversial. Previous studies concerning Ureaplasma spp. and male infertility have been confined to the species level of Ureaplasma. Currently, an expanded multilocus sequence typing (eMLST) scheme has been established with high discriminatory power. The aim of this study was to use eMLST to explore the distribution of Ureaplasma spp. and to analyze its role in oligozoospermia and semen quality. A total of 480 semen samples were obtained from Chinese infertile males. The associations between Ureaplasma spp. with oligozoospermia and semen characteristics were further evaluated. Phylogenetic analysis revealed that 102 Ureaplasma spp. could be separated into two clusters and seven sub-groups. Within cluster I (U. parvum), eST16 and eST41 were the most frequent clones. For cluster II (U. urealyticum), eST82 and eST147 were the most prevalent clones. Sub-groups A and C belonging to cluster I and sub-group 1 belonging to cluster II showed an association with oligozoospermia, in contrast with the Ureaplasma spp. negative group (P < 0.05). Compared with the negative group, semen motility decreased in sub-group 2, especially for non-progressive motility (P < 0.05). These results indicated that sub-groups A and C belonging to cluster I (U. parvum) and sub-group 1 belonging to cluster II (U. urealyticum) were shown to be associated with oligozoospermia. Sub-group 2 belonging to cluster II may have the ability to impair semen motility, especially for non-progressive motility.
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http://dx.doi.org/10.1007/s10096-018-3331-6DOI Listing
October 2018

Biochanin A partially restores the activity of ofloxacin and ciprofloxacin against topoisomerase IV mutation-associated fluoroquinolone-resistant Ureaplasma species.

J Med Microbiol 2017 Nov 6;66(11):1545-1553. Epub 2017 Oct 6.

Biomedical Research Center, Sir Run Run Shaw Hospital, School of Medicine, Zhejiang University, Hangzhou, Zhejiang 310016, PR China.

Purpose: This study aims to investigate the synergistic antimicrobial activity of four phytoalexins in combination with fluoroquinolones against Ureaplasma spp., a genus of cell wall-free bacteria that are intrinsically resistant to many available antibiotics, making treatment inherently difficult.

Methodology: A total of 22 958 urogenital tract specimens were assessed for Ureaplasma spp. identification and antimicrobial susceptibility. From these, 31 epidemiologically unrelated strains were randomly selected for antimicrobial susceptibility testing to determine the minimum inhibitory concentration (MIC) of four fluoroquinolones and the corresponding quinolone resistance-determining regions (QRDRs). Synergistic effects between fluoroquinolones and four phytoalexins (reserpine, piperine, carvacrol and biochanin A) were evaluated by fractional inhibitory concentration indices (FICIs).

Results: Analysis of the QRDRs suggested a vital role for the mutation of Ser-83→Leu in ParC in fluoroquinolone-resistant strains, and the occurrence of mutations in QRDRs showed significant associations with the breakpoint of levofloxacin. Moreover, diverse synergistic effects of the four phytoalexins with ofloxacin or ciprofloxacin were observed and biochanin A was able to enhance the antimicrobial activity of fluoroquinolones significantly.

Conclusion: This is the first report of the antimicrobial activity of biochanin A in combination with fluoroquinolones against a pathogenic mycoplasma, and opens up the possibility of using components of biochanin A as a promising therapeutic option for treating antibiotic-resistant Ureaplasma spp. infections.
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http://dx.doi.org/10.1099/jmm.0.000598DOI Listing
November 2017

Effects of germination on the nutritional properties, phenolic profiles, and antioxidant activities of buckwheat.

J Food Sci 2015 May 9;80(5):H1111-9. Epub 2015 Apr 9.

Wilmar (Shanghai) Biotechnology Research and Development Center Co., Ltd, No. 118 Gaodong Rd., Pudong New District, Shanghai, 200137, China.

Germination is considered to be an effective process for improving the nutritional quality and functionality of cereals. In this study, changes of nutritional ingredients, antinutritional components, chemical composition, and antioxidant activities of buckwheat seeds over 72 h of germination were investigated, and the reasons for these changes are discussed. With the prolonged germination time, the contents of crude protein, reducing sugar, total phenolics, total flavonoids, and condensed tannins increased significantly, while the levels of crude fat, phytic acid, and the activity of trypsin inhibitor decreased. Phenolic compounds, such as rutin, vitexin, isovitexin, orientin, isoorientin, chlorogenic acid, trans-3-hydroxycinnamic acid, and p-hydroxybenzoic acid increased significantly during the germination process, which may be due to the activation of phenylalanine ammonialyase. The improvement of flavonoids led to significant enhancement of the antioxidant activities of germinated buckwheat. Germinated buckwheat had better nutritional value and antioxidant activities than ungerminated buckwheat, and it represented an excellent natural source of flavonoids and phenolic compounds, especially rutin and C-glycosylflavones. Therefore, germinated buckwheat could be used as a promising functional food for health promotion.
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http://dx.doi.org/10.1111/1750-3841.12830DOI Listing
May 2015

Effect of black soybean extract on the suppression of the proliferation of human AGS gastric cancer cells via the induction of apoptosis.

J Agric Food Chem 2011 May 11;59(9):4597-605. Epub 2011 Apr 11.

Department of Cereal and Food Science, North Dakota State University , Fargo, North Dakota 58108-6050, United States.

Black soybean is known to have a health-promoting effect because of its high content of polyphenolic compounds and antioxidant activities. The objective of the present study was to investigate the chemopreventive effects of black soybean extract against human AGS gastric cancer cells and its possible mechanism in inducing apoptosis. Black soybean extract was obtained by extracting black soybean with acidified aqueous acetone, and its phytochemical constituents, as determined by HPLC-DAD methods, were demonstrated to contain various phenolics. The black soybean extract inhibited AGS cell growth in a dose-dependent manner with an IC(50) of 3.69 mg/mL as measured by the MTT assay. This growth inhibition effect was further confirmed by the CFDA-SE assay. Flow cytometry analysis showed that black soybean extract dose-dependently induced apoptosis of AGS cells. Moreover, the involvement of black soybean extract in inducing apoptosis was confirmed by the expression of Bax, Bcl-2, caspase-3, and PARP. The results of the present study indicated that black soybean extract could be used as an apoptosis inducer in AGS cells and a natural chemopreventive agent in the treatment of human gastric cancer.
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http://dx.doi.org/10.1021/jf104945xDOI Listing
May 2011

Antioxidant activity and phenolic compositions of lentil (Lens culinaris var. Morton) extract and its fractions.

J Agric Food Chem 2011 Mar 18;59(6):2268-76. Epub 2011 Feb 18.

Department of Cereal and Food Science, College of Pharmacy, Nursing, and Allied Sciences, North Dakota State University, Fargo, North Dakota 58108-6050, United States.

Phenolic compounds were extracted from Morton lentils using acidified aqueous acetone. The crude Morton extract (CME) was applied onto a macroresin column and desorbed by aqueous methanol to obtain a semipurified Morton extract (SPME). The SPME was further fractionated over a Sephadex LH-20 column into five main fractions (I-V). The phytochemical contents such as total phenolic content (TPC), total flavonoid content (TFC), and condensed tannin content (CTC) of the CME, SPME, and its fractions were examined by colorimetric methods. Antioxidant activity of extracts and fractions were screened by DPPH scavenging activity, Trolox equivalent antioxidant capacity (TEAC), ferric reduced antioxidant power (FRAP), and oxygen radical absorbing capacity (ORAC) methods. In addition, the compositions of active fractions were determined by HPLC-DAD and HPLC-MS methods. Results showed that the fraction enriched in condensed tannins (fraction V) exhibited significantly higher values of TPC, CTC, and antioxidant activity as compared to the crude extract, SPME, and low molecular weight fractions (I-IV). Eighteen compounds existed in those fractions, and 17 were tentatively identified by UV and MS spectra. HPLC-MS analysis revealed fraction II contained mainly kaempferol glycoside, fractions III and IV mainly contained flavonoid glycosides, and fraction V was composed of condensed tannins. The results suggested that the extract of Morton lentils is a promising source of antioxidant phenolics and may be used as a dietary supplement for health promotion.
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http://dx.doi.org/10.1021/jf104640kDOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC3063125PMC
March 2011

Comparative studies on the chemical and cell-based antioxidant activities and antitumor cell proliferation properties of soy milk manufactured by conventional and commercial UHT methods.

J Agric Food Chem 2010 Mar;58(6):3558-66

Food Science and Technology Program, Beijing Normal University-Hong Kong Baptist University-United International College, Zhuhai, China.

The aims of this work were to compare antiproliferation, antioxidant activities and total phytochemicals and individual isoflavone profiles in soy milk processed by various methods including traditional stove cooking, direct steam injection, direct ultrahigh temperature (UHT), indirect UHT, and a two-stage simulated industry method, and a selected commercial soy milk product. Various processing methods significantly affected total saponin, phytic acid, and total phenolic content and individual isoflavone distribution. The laboratory UHT and the two-stage processed soy milk exhibited relatively higher total phenolic content, total flavonoid content, saponin and phytic acid than those processed by the traditional and steam processed methods. Thermal processing caused obvious intertransformation but did not cause severe degradation except for breaking down of aglycons. Thermal processing significantly increased antioxidant capacities of soy milk determined by chemical analyses, but decreased cellular antioxidant capacities as compared to the raw soy milk. The raw and all processed soy milk exhibited antipoliferative activities against human HL-60 leukemia cells, AGS gastric tumor cells, and DU145 prostate cancer cells in a dose-dependent manner. The raw soy milk, but not the processed soy milk, exhibited a dose-dependent antiproliferative effect against colorectal adenocarcinoma Caco-2 cells. Taken together, these results indicate that various thermal processing methods change not only phytochemcials but also potential health-promoting effects of soy milk.
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http://dx.doi.org/10.1021/jf903796cDOI Listing
March 2010

Antioxidant effects of phlorotannins isolated from Ishige okamurae in free radical mediated oxidative systems.

J Agric Food Chem 2008 Aug 11;56(16):7001-9. Epub 2008 Jul 11.

Marine Bioprocess Research Center, Pukyong National University, Busan 608-737, South Korea.

Three phlorotannins, including phloroglucinol, diphlorethohydroxycarmalol, and 6,6'-bieckol, were isolated from Ishige okamurae by column chromatography. The structures of the phlorotannins were determined on the basis of spectroscopic analysis, including NMR and mass spectrometry (MS) techniques. Antioxidant effects of phlorotannins were measured by direct free radical scavenging activities using the electron spin resonance spectrometry (ESR) technique and cellular systems in vitro. The results indicated that diphlorethohydroxycarmalol and 6,6'-bieckol showed potential radical scavenging activities against the 2,2-diphenyl-1-picrylhydrazyl (DPPH), hydroxyl, alkyl, and superoxide radicals. Moreover, no cytotoxicities of the phlorotannins on human fetal lung fibroblasts cell line (MRC-5), mouse macrophages cell line (RAW264.7), and human leukemic cell line (HL-60) were observed. In addition, diphlorethohydroxycarmalol and 6,6'-bieckol significantly reduced the intracellular reactive oxygen species level assessed by 2',7'-dichlorofluorescein diacetate (DCFH-DA) assay in RAW264.7 cells, and myeloperoxide (MPO) activity in HL-60 cells and radical-mediated oxidation of cell membrane proteins in RAW264.7 cells were dose-dependently inhibited in the presence of diphlorethohydroxycarmalol and 6,6'-bieckol. In conclusion, these results suggested that phlorotannins could be used as novel functional foodstuffs or antioxidants in the cosmetic and drug industries.
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http://dx.doi.org/10.1021/jf801133hDOI Listing
August 2008

Hypocholesterolemic effects of a flavonoid-rich extract of Hypericum perforatum L. in rats fed a cholesterol-rich diet.

J Agric Food Chem 2005 Apr;53(7):2462-6

State Key Laboratory of Bioreactor Engineering, New World Institute of Biotechnology, East China University of Science and Technology, Shanghai 200237, China.

In a previous study, a flavonoid-rich extract of Hypericum perforatum L. (FEHP) was prepared and its antioxidant activity was determined by a series of models in vitro. In this study, the hypocholesterolemic effects of FEHP in rats fed a cholesterol-rich diet were tested. Forty Wistar rats fed a standard laboratory diet or a cholesterol-rich diet for 16 weeks were used. The serum lipid levels, as well as malondialdehyde (MDA) and activity of superoxide dismutase (SOD) and catalase (CAT) in serum and liver, were examined. Cholesterol-rich diet induced hypercholesterolemia was manifested in the elevation of serum lipid levels such as total cholesterol (TC), total triglycerides (TG), and low density lipoprotein cholesterol (LDL-C). Administration of middle-dose (75 mg/kg of BW/day) and high-dose (150 mg/kg of BW/day) FEHP significantly lowered the serum levels of TC, TG, and LDL-C, while increasing the serum level of high density lipoprotein cholesterol (HDL-C). Also, the content of MDA in serum and liver decreased significantly after oral administration of FEHP compared with those of rats fed a cholesterol-rich diet. In addition, FEHP increased the activity of SOD in serum and liver, but the activity of CAT was significantly elevated only in liver. These results suggested that the hypocholesterolemic effects of FEHP might be due to its abilities to lower serum TC, TG, and LDL-C levels as well as to slow the lipid peroxidation process and to enhance the antioxidant enzyme activity.
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http://dx.doi.org/10.1021/jf048469rDOI Listing
April 2005

Antioxidant activity of a flavonoid-rich extract of Hypericum perforatum L. in vitro.

J Agric Food Chem 2004 Aug;52(16):5032-9

State Key Laboratory of Bioreactor Engineering, Institute of Biochemistry, East China University of Science and Technology, Shanghai, 200237, China.

A flavonoid-rich extract of Hypericum perforatum L. (FEHP) was prepared by adsorption on macroporous resin and desorption by ethanol. Total flavonoid content of FEHP was determined by a colorimetric method. The major constituents of FEHP, including rutin, hyperoside, isoquercitrin, avicularin, quercitrin, and quercetin, were determined by HPLC analysis and confirmed by LC-MS. Different antioxidant assays were utilized to evaluate free radical scavenging activity and antioxidant activity of FEHP. FEHP was an effective scavenger in quenching DPPH and superoxide radical with IC50 of 10.63 microg/mL and 54.3 microg/mL, respectively. A linear correlation between concentration of FEHP and reducing power was observed with a coefficient of r2 = 0.9991. Addition of 150 microg of FEHP obviously decreased the peroxidation of linoleic acid during 84 h incubation, but the amount of FEHP over 150 microg did not show statistically significant inhibitory effect of peroxidation of linoliec acid (p > 0.05). FEHP exhibited inhibitory effect of peroxidation of liposome induced both by hydroxyl radical generated with iron-ascorbic acid system and peroxyl radical and showed prominent inhibitory effect of deoxyribose degradation in a concentration-dependent manner in site-specific assay but poor effect in non-site-specific assay, which suggested that chelation of metal ion was the main antioxidant action. According to the results obtained in the present study, the antioxidant mechanism of FEHP might be attributed to its free radical scavenging activity, metal-chelation activity, and reactive oxygen quenching activity.
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http://dx.doi.org/10.1021/jf049571rDOI Listing
August 2004