Guoyin Kai

Shanghai Normal University, Ling-ch’uan, Guangxi Zhuangzu Zizhiqu, China

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Publications (56)135.1 Total impact

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    ABSTRACT: The dietary polyphenols as aldose reductases inhibitors (ARIs) have attracted great interest among researchers. The aim of this review is to give an overview of the research reports on the structure-activity relationship of dietary polyphenols inhibiting aldose reductases (AR). The molecular structures influence the inhibition of the following: (1) The methylation and methoxylation of the hydroxyl group at C3, C3', and C4' of flavonoids decreased or little affected the inhibitory potency. However, the methylation and methoxylation of the hydroxyl group at C5, C6, and C8 significantly enhanced the inhibition. Moreover, the methylation and methoxylation of C7-OH influence the inhibitory activity depending on the substitutes on rings A and B of flavonoids. (2) The glycosylation on 3-OH of flavonoids significantly increased or little affected the inhibition. However, the glycosylation on 7-OH and 4'-OH of flavonoids significantly decreased the inhibition. (3) The hydroxylation on A-ring of flavones and isoflavones, especially at positions 5 and 7, significantly improved the inhibition and the hydroxylation on C3' and C4' of B-ring of flavonoids remarkably enhanced the inhibition; however, the hydroxylation on the ring C of flavones significantly weakened the inhibition. (4) The hydrogenation of the C2˭C3 double bond of flavones reduced the inhibition. (5) The hydrogenation of α=β double bond of stilbenes hardly affected the inhibition and the hydroxylation on C3' of stilbenes decreased the inhibition. Moreover, the methylation of the hydroxyl group of stilbenes obviously reduced the activity. (6) The hydroxylation on C4 of chalcone significantly increased the inhibition and the methylation on C4 of chalcone remarkably weakened the inhibition.
    Critical Reviews in Food Science and Nutrition 01/2015; 55(1):16-31. · 4.82 Impact Factor
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    ABSTRACT: Tanshinone is widely used for treatment of cardio-cerebrovascular diseases with increasing demand. Herein, key enzyme genes SmHMGR (3-hydroxy-3-methylglutaryl CoA reductase) and SmDXR (1-deoxy-D-xylulose 5-phosphate reductoisomerase) involved in the tanshinone biosynthetic pathway were introduced into Salvia miltiorrhiza (Sm) hairy roots to enhance tanshinone production. Over-expression of SmHMGR or SmDXR in hairy root lines can significantly enhance the yield of tanshinone. Transgenic hairy root lines co-expressing HMGR and DXR (HD lines) produced evidently higher levels of total tanshinone (TT) compared with the control and single gene transformed lines. The highest tanshinone production was observed in HD42 with the concentration of 3.25 mg g(-1) DW. Furthermore, the transgenic hairy roots showed higher antioxidant activity than control. In addition, transgenic hairy root harboring HMGR and DXR (HD42) exhibited higher tanshinone content after elicitation by yeast extract and/or Ag(+) than before. Tanshinone can be significantly enhanced to 5.858, 6.716, and 4.426 mg g(-1) DW by YE, Ag(+), and YE-Ag(+) treatment compared with non-induced HD42, respectively. The content of cryptotanshinone and dihydrotanshinone was effectively elevated upon elicitor treatments, whereas there was no obvious promotion effect for the other two compounds tanshinone I and tanshinone IIA. Our results provide a useful strategy to improve tanshinone content as well as other natural active products by combination of genetic engineering with elicitors.
    Functional & integrative genomics. 06/2014;
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    ABSTRACT: Acrylamide (AA) was firstly detected in food in 2002, and since then, studies on AA analysis, occurrence, formation, toxicity, risk assessment and mitigation have been extensively carried out, which have greatly advanced understanding of this particular biohazard at both academic and industrial levels. There is considerable variation in the levels of AA in different foods and different brands of the same food; therefore, so far, a general upper limit for AA in food is not available. In addition, the link of dietary AA to human cancer is still under debate, although AA has been known as a potential cause of various toxic effects including carcinogenic effects in experimental animals. Furthermore, the oxidized metabolite of AA, glycidamide (GA), is more toxic than AA. Both AA and GA can form adducts with protein, DNA, and hemoglobin, and some of those adducts can serve as biomarkers for AA exposure; their potential roles in the linking of AA to human cancer, reproductive defects or other diseases, however, are unclear. This review addresses the state-of-the-art understanding of AA, focusing on risk assessment, mechanism of formation and strategies of mitigation in foods. The potential application of omics to AA risk assessment is also discussed.
    Food and chemical toxicology: an international journal published for the British Industrial Biological Research Association 04/2014; · 2.99 Impact Factor
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    ABSTRACT: Tanshinone is a group of active diterpenes which are widely used in the treatment of cardiovascular disease. In this study, methyl jasmonate (MJ) and salicylic acid (SA) were used to investigate their effects on tanshinone accumulation and biosynthetic genes expression in the hairy roots of geranylgeranyl diphosphate synthase (SmGGPPS) overexpression line (G50) in Salvia miltiorrhiza. High performance liquid chromatography (HPLC) analysis showed that total tanshinone content in G50 was obviously increased by 3.10-fold (11.33 mg/g) with MJ at 36 h and 1.63 times (5.95 mg/g) after SA treatment for 36 h in comparison to their mimic treatment control. Furthermore, Quantitative reverse transcription PCR (qRT-PCR) analysis showed that the expression of SmIPPI, SmGGPPS, SmCPS and SmKSL increased significantly with MJ treatment. However, the expression of SmIPPI reached the highest level at 144 h while those of SmGGPPS, SmCPS and SmKSL only increased slightly with SA treatment. The two elicitor treatments suggested that tanshinone accumulation positively correlated to the expression of key genes such as SmGGPPS, SmCPS and SmKSL. Meanwhile the study also indicated that it was a feasible strategy to combine elicitor treatment with transgenic technology for enhancement of tanshinone, which paved the way for further metabolic engineering of tanshinone biosynthesis.This article is protected by copyright. All rights reserved
    Biotechnology and Applied Biochemistry 04/2014; · 1.35 Impact Factor
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    ABSTRACT: Acrylamide (AA) was firstly detected in food in 2002, and since then, studies on AA analysis, occurrence, formation, toxicity, risk assessment and mitigation have been extensively carried out, which have greatly advanced understanding of this particular biohazard at both academic and industrial levels. There is considerable variation in the levels of AA in different foods and different brands of the same food; therefore, so far, a general upper limit for AA in food is not available. In addition, the link of dietary AA to human cancer is still under debate, although AA has been known as a potential cause of various toxic effects including carcinogenic effects in experimental animals. Furthermore, the oxidized metabolite of AA, glycidamide (GA), is more toxic than AA. Both AA and GA can form adducts with protein, DNA, and hemoglobin, and some of those adducts can serve as biomarkers for AA exposure; their potential roles in the linking of AA to human cancer, reproductive defects or other diseases, however, are unclear. This review addresses the state-of-the-art understanding of AA, focusing on risk assessment, mechanism of formation and strategies of mitigation in foods. The potential application of omics to AA risk assessment is also discussed.
    Food and Chemical Toxicology. 01/2014;
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    ABSTRACT: The inhibitory effects of dietary polyphenols against α-amylase have attracted great interest among researchers. The aim of this review is to give an overview of the research reports on the structure-activity relationship of polyphenols inhibiting α-amylase. The molecular structures that influence the inhibition are the following: (1) The hydroxylation of flavonoids improved the inhibitory effect on α-amylase; (2) Presence of an unsaturated 2,3-bond in conjugation with a 4-carbonyl group has been associated with stronger inhibition; (3) The glycosylation of flavonoids decreased the inhibitory effect on α-amylase depending on the conjugation site and the class of sugar moiety; (4) The methylation and methoxylation of flavonoids obviously weakened the inhibitory effect; (5) The galloylated catechins have higher inhibition than nongalloylated catechins; the catechol-type catechins were stronger than the pyrogallol-type catechins; the inhibition activities of the catechins with 2,3-trans structure were higher than those of the catechins with 2,3-cis structure; (6) Cyanidin-3-glucoside showed higher inhibition against than cyanidin and cyanidin-3-galactoside and cyanidin-3,5-diglucoside had no inhibitory activity; (7) Ellagitannins with β-galloyl groups at glucose C-1 positions have higher inhibitory effect than the α-galloyl and nongalloyl compounds and the molecular weight of ellagitannins is not an important element.
    Critical reviews in food science and nutrition 01/2013; 53(5):497-506. · 3.73 Impact Factor
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    ABSTRACT: The dietary polyphenols as α-glucosidases inhibitors have attracted great interest among researchers. The aim of this review is to give an overview of the research reports on the structure-activity relationship of dietary polyphenols inhibiting α-glucosidases. The molecular structures that influence the inhibition are the following: (1) The hydroxylation and galloylation of flavonoids including catechins improve the inhibitory activity. (2) The glycosylation of hyroxyl group and hydrogenation of the C2=C3 double bond on flavonoids weaken the inhibition. (3) However, cyaniding glycosides show higher inhibition against than cyanidin. Proanthocyanidins oligomers exhibit a stronger inhibitory activity than their polymers. (4) The hydroxylation on B ring and the glycosylation of stilbenes reduce the inhibitory activity. (5) Caffeoylquinic acids display strong inhibition against α-glucosidases. However, hydroxycinnamic acid, ferulic acid, and gallic acid hardly inhibited α-glucosidases. (6) The coupled galloyl structures attached to C-3 and C-6 of the 4C(1) glucose core of ellagitanin gave basic inhibitory activity. (7) The mono-glycosylation of chalcones slightly lowers the inhibition. However, the diglycosylation of chalcones significantly decreased the activity.
    Critical reviews in food science and nutrition 01/2013; 53(8):818-36. · 3.73 Impact Factor
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    ABSTRACT: Tropane alkaloids (TA) including hyoscyamine, anisodamine, scopolamine and anisodine, are used medicinally as anticholinergic agents with increasing market demand, so it is very important to improve TA production by metabolic engineering strategy. Here, we report the simultaneous introduction of genes encoding the branch-controlling enzyme tropinone reductase I (TRI, EU424321) and the downstream rate-limiting enzyme hyoscyamine-6β-hydroxylase (H6H, EF187826) involved in TA biosynthesis into Anisodus acutangulus hairy roots by Agrobacterium-mediated gene transfer technology. Transgenic hairy root lines expressing both TRI and H6H (TH lines) produced significantly higher (P < 0.05) levels of TA compared with the control and single gene transformed lines (T or H lines). The best double gene transformed line (TH53) produced 4.293 mg g(-1) TA, which was about 4.49-fold higher than that of the control lines (0.96 mg g(-1)). As far as it is known, this is the first report on simultaneous introduction of TRI and H6H genes into TA-producing plant by biotechnological approaches. Besides, the content of anisodine was also greatly improved in A. acutangulus by over-expression of AaTRI and AaH6H genes. The average content of anisodine in TH lines was 0.984 mg g(-1) dw, about 18.57-fold of BC lines (0.053 mg g(-1) dw). This is the first time that this phenomenon has been found in TA-producing plants.
    Molecular BioSystems 09/2012; 8(11):2883-90. · 3.35 Impact Factor
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    ABSTRACT: The aphid is one of the most serious pests that causes damage to crops worldwide. Lectins from Araceae plant had been proved useful to control the aphid. Herein, the full-length cDNA of Monstera deliciosa agglutinin (mda) gene was cloned and then introduced into tobacco and the influence of the expression of mda in transgenic tobacco against peach-potato aphids (Myzus persicae) was investigated. Among 92 regenerated plants, 59 positive tobacco lines were obtained. Real-time PCR assays and aphid bioassay test revealed that there is a positive correlation between the expression level of mda and the inhibitory effect on peach-potato aphids. The average anti-pests ability of mda transgenic tobacco was 74%, which was higher than that of other reported lectins from Araceae plant. These results indicated that MDA is one of promising insect resistance proteins selected for the control of peach-potato aphids.
    Integrative Biology 06/2012; 4(8):937-44. · 4.32 Impact Factor
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    ABSTRACT: Diabetes is characterized by an elevated level of glucose in the blood. This glucose can form covalent adducts with plasma proteins through a non-enzymatic process known as glycation. It has been suggested that the increasing glycation can influence the ability of plasma proteins to bind to small molecules. Herein, the difference between healthy human plasma proteins (HPP) and type II diabetes plasma proteins (TPP) in binding small molecules was investigated. TPP showed about 1-10 times lower affinities for polyphenols than HPP. The values of lg K(a)(HPP) are positive proportional to the values of lg K(a)(TPP) with excellent linear relationship. The glycation of HPP decreased the affinities for HPP by about 1.17 to 16.6 times. The difference between HPP-polyphenol interaction and TPP-polyphenol interaction was bigger for the more lipophilic polyphenols. The affinities for TPP or HPP slightly decreased with increasing hydrogen bond donor numbers of polyphenols and hardly changed with hydrogen bond acceptor numbers.
    Integrative Biology 03/2012; 4(5):502-7. · 4.32 Impact Factor
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    Jianbo Xiao, Guoyin Kai
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    ABSTRACT: The interactions between polyphenols, especially flavonoids and plasma proteins, have attracted great interest among researchers. Few papers, however, have focused on the structure-affinity relationship of polyphenols on their affinities for plasma proteins. The aim of this review is to give an overview of the research reports on the characterization, influence on the bioactivity, and the structure-affinity relationship for studying the affinities between polyphenols and plasma proteins. The molecular properties that influence the affinities of polyphenols for plasma proteins are the following: 1) One or more hydroxyl groups in the B-ring (e.g., 3',4' dihydroxylated B ring catechol group) of flavonoids enhanced the binding affinities to proteins. However, the hydroxyl group in the C-ring will weaken the binding interaction. 2) The presence of an unsaturated 2,3-bond in conjugation with a 4-carbonyl group, characteristic of flavonols structure, has been associated with stronger binding affinity with plasma proteins; 3) The glycosylation of flavonoids decreases the affinities for plasma proteins by 1-3 orders of magnitude depending on the conjugation site and the class of sugar moiety; 4) The methylation of hydroxyl groups in flavonoids slightly enhanced the affinities for plasma proteins by 2-16 times; 5) The galloylated catechins have higher binding affinities for plasma proteins than do non-galloylated catechins and the pyrogallol-type catechins have higher affinities than do the catechol-type catechins. The affinity of the catechin with 2,3-trans structure was lower than those of the catechin with 2,3-cis structure; 6) The gallotannins with more gallol groups presented a much higher percentage of binding to plasma proteins. α-D-Gallotannin showed a greater affinity for plasma proteins than does the natural stereoisomer, β-D-gallotannin; 7) The binding degree of chlorogenic acid with only one caffeoyl group was lower than the binding degrees of caffeoyl quinic acids with more caffeoyl groups. The methylation of phenolic acid decreased the affinity for BSA.
    Critical reviews in food science and nutrition 01/2012; 52(1):85-101. · 3.73 Impact Factor
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    ABSTRACT: The molecular structure/property-affinity relationships of dietary polyphenols non-covalently binding to total plasma proteins of type II diabetes (IIDTPP) were investigated by comparing the binding constants obtained from the fluorescence titration method. An additional methoxy group in flavonoids increased their binding affinities for IIDTPP by 1.38 to 15.85 times. The hydroxylation at the 4' position (Ring B) of flavonols and the 5 position (Ring A) of isoflavones weakened the binding affinities; however, hydroxylation at other positions on flavonoids slightly enhanced or little affected the binding affinities for IIDTPP. The glycosylation of flavonoids slightly decreased or little affected the affinities for IIDTPP by less than 1 order of magnitude. The hydrogenation of the C2[double bond, length as m-dash]C3 double bond of flavone, 6-hydroxyflavone, 6-methoxyflavone and myricetin decreased the binding affinities. The galloylation of catechins significantly improved the binding affinities with IIDTPP approximately 10 to 1000 times. The esterification of gallic acid increased its binding affinity. The hydrophobic force played an important role in the binding interaction between polyphenols and IIDTPP.
    Integrative Biology 09/2011; 3(11):1087-94. · 4.32 Impact Factor
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    ABSTRACT: The four tropane alkaloids have played a pivotal role in controlling diseases such as the toxic and septic shock, the organophosphorus poison and the acute lung injury. Here, the elicitation effect of different elicitors on the production of tropane alkaloids and the molecular mechanism of enzyme genes in the pathway was firstly demonstrated in hairy roots of Anisodus acutangulus. The results showed ethanol, methyl jasmonate and Ag(+) could improve the accumulation of tropane alkaloids up to 1.51, 1.13 and 1.08 times after 24 h treatment, respectively (P < 0.05), whereas salicylic acid decreased the average content of tropane alkaloids. Furthermore, expression profile analysis results revealed that up-regulation of hyoscyamine-6b-hydroxylase (AaH6H) and little regulation of tropinone reducase II (AaTR2) elicited by ethanol, increased expression of putrescine N-methyltransferase I (AaPMT1) elicited by Ag(+), elevated expression of tropinone reducase I (AaTR1) elicited by methyl jasmonate, respectively, resulted in tropane alkaloids improvement. Our results showed that hairy root culture of A. acutangulus in combination with elicitors was a promising way for production of tropane alkaloids in the future.
    Molecular Biology Reports 05/2011; 39(2):1721-9. · 2.51 Impact Factor
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    ABSTRACT: Zero-dimensional nanostructures such as ZnO#ZnS QDs heterojunctures (QDHJs) are green nanoparticles and have gained a tremendous amount of attention. However, very little information is available on the effects of these heterojunctures on the transportation of drugs in blood. Herein, stilbenes were studied for their affinities for common bovine plasma proteins (CBPP) in the presence and absence of QDHJs with different diameters. The affinities of QDHJs for CBPP improved with increasing QDHJs size. QDHJs improved the affinities of resveratrol and polydatin for CBPP by 14.74% to 22.36% and 12.56% to 21.34% depending on the size of QDHJs. The number of binding sites (n) between resveratrol and polydatin for CBPP in the presence of QDHJs were 1.04 ± 0.03 and 1.06 ± 0.04, which were obviously higher than those in the absence of QDHJs (n = 0.89 and 0.92). QDHJs in blood will decrease the free concentration of stilbenes and weaken their pharmacological effects.
    Molecular BioSystems 05/2011; 7(8):2452-8. · 3.35 Impact Factor
  • Jianbo Xiao, Guoyin Kai, Xiaoqing Chen
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    ABSTRACT: Recently, investigations of biological toxicity of cadmium QDs and their toxic interaction with plasma proteins have attracted great interest. In this work, flavonoids were studied for the affinities for human serum albumin (HSA) in the presence and absence of CdTe G-QDs by fluorescence quenching method. CdTe G-QDs obviously enhanced the binding affinities of kaempferol, genistein and biochanin A by 3.78 to 154.88 times depending on the QDs concentration. However, the affinity of kaempferide for HSA was slightly weakened in the presence of G-QDs. The non-methylated flavonoids were more sensitive to G-QDs than their methylated forms. The affinities of kaempferide and kaempferol for HSA at first were slightly improved and then obviously decreased with increasing G-QDs concentration. For genistein, the affinities for HSA decreased with increasing G-QDs concentration. However, the G-QDs concentration showed no obvious effect on the affinity of biochanin A. The binding affinities of flavonoids for HSA improved with increasing QDs size.
    Nanotoxicology 05/2011; 6(3):304-14. · 7.84 Impact Factor
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    ABSTRACT: As more and more genetically modified (GM) crops are approved for commercialization and planting, the development of quick and on-spot methods for GM crops and their derivates is required. Herein, we established the polymerase chain reaction and agarose gel electrophoresis-free system for the identification of seven GM maize events (DAS-59122-7, T25, BT176, TC1507, MON810, BT11, and MON863) employing a loop-mediated isothermal amplification (LAMP) technique. The LAMP assay was performed using a set of four specific primers at 60-65 °C in less than 40 min, and the results were observed by direct visual observation. In these developed assays, the specificity targeted at each GM maize event based on the event-specific sequence was well confirmed, and the limits of detection were as low as four copies of maize haploid genomic DNA with an exception of 40 copies for MON810 assay. Furthermore, these developed assays were successfully used to test six practical samples with different GM maize events and contents (ranged from 0.0 to 2.0%). All of the results indicated that the established event-specific visual LAMP assays are more convenient, rapid, and low-cost for GM maize routine analysis.
    Journal of Agricultural and Food Chemistry 05/2011; 59(11):5914-8. · 2.91 Impact Factor
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    ABSTRACT: The relationship between the structural properties of natural polyphenols and their affinities for α-amylase were investigated by fluorescence titration analysis. The binding process with α-amylase was strongly influenced by the structural differences of the compounds under study. For instance, the methylation of the hydroxyl group in flavonoids increased their binding affinities for α-amylase by 2.14 to 7.76 times. The hydroxylation on rings A, B, and C of flavonoids also significantly affected their affinities for α-amylase. The glycosylation of isoflavones and flavanones reduced their affinities for α-amylase and the glycosylation of flavones and flavonols enhanced their affinities for α-amylase. Hydrogenation of the C2=C3 double bond of flavonoids decreased the binding affinities. The galloylated catechins had higher binding affinities with α-amylase than non-galloylated catechins and the pyrogallol-type catechins had higher affinities than the catechol-type catechins. The presence of the galloyl moiety is the most decisive factor. The glycosylation of resveratrol decreased its affinity for α-amylase. The esterification of gallic acid significantly reduced the affinity for α-amylase. The binding interaction between polyphenols and α-amylase was mainly caused by hydrophobic forces.
    Molecular BioSystems 03/2011; 7(6):1883-90. · 3.35 Impact Factor
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    ABSTRACT: Hyoscyamine 6β-hydroxylase (H6H; EC 1.14.11.11) converts hyoscyamine to scopolamine in the last step of scopolamine biosynthetic pathway. The gene encoding H6H in Anisodus acutangulus was cloned and expressed in Escherichia coli and the recombinant proteins fused with His-tag or GST-tag at its N-terminal were purified and then confirmed by Western bolt analysis. The biofunctional assay revealed that the His-AaH6H and GST-AaH6H converted hyoscyamine (40 mg/l) to scopolamine at 32 and 31 mg/l, respectively. This is the first report on AaH6H expression, purification and functional characterization facilitates further genetic improvement of scopolamine yield in A. acutangulus.
    Biotechnology Letters 03/2011; 33(7):1361-5. · 1.85 Impact Factor
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    ABSTRACT: The molecular property-affinity relationship of dietary flavonoids for bovine gamma-globulin (γ-globulin) was investigated by fluorescence titration analysis. The quenching effects of flavonoids on γ-globulin fluorescence depended on the structures of flavonoids. The magnitudes of binding constants between flavonoids and γ-globulin were within the range of 10(3)-10(5) L mol(-1). These data were much smaller than the affinities between flavonoids and purified bovine and human serum albumins. The affinities of flavonoids for γ-globulin were strongly influenced by the structural differences of the compounds under study. The affinities for γ-globulin decreased with increasing partition coefficients and increased with increasing hydrogen bond acceptor numbers of flavonoids, which suggested that the binding interaction was mainly caused by hydrogen bond forces.
    Food & function. 02/2011; 2(2):137-41.

Publication Stats

465 Citations
135.10 Total Impact Points

Institutions

  • 2007–2014
    • Shanghai Normal University
      Ling-ch’uan, Guangxi Zhuangzu Zizhiqu, China
  • 2012
    • Central South University
      • Department of Biochemistry
      Changsha, Hunan, China
  • 2004–2007
    • Fudan University
      • State Key Laboratory of Genetic Engineering
      Shanghai, Shanghai Shi, China
  • 2003–2007
    • Shanghai Jiao Tong University
      • School of Agriculture and Biology
      Shanghai, Shanghai Shi, China
  • 2004–2006
    • Shanghai University
      Shanghai, Shanghai Shi, China