[Identification and expression of uridine diphosphate glycosyltransferase(UGT) gene family from Dendrobium officinale].

Uridine diphosphate glycosyltransferase(UGT) is a highly conserved protein in plants, which usually functions in secondary metabolic pathways. This study used the Hidden Markov Model(HMM) to screen out members of UGT gene family in the whole genome of Dendrobium officinale, and 44 UGT genes were identified. Bioinformatics was used to analyze the structure, phylogeny, and promoter region components of D. officinale genes. The results showed that UGT gene family could be divided into four subfamilies, and UGT gene structure was relatively conserved in each subfamily, with nine conserved domains. The upstream promoter region of UGT gene contained a variety of cis-acting elements related to plant hormones and environmental factors, indicating that UGT gene expression may be induced by plant hormones and external environmental factors. UGT gene expression in different tissues of D. officinale was compared, and UGT gene expression was found in all parts of D. officinale. It was speculated that UGT gene played an important role in many tissues of D. officinale. Through transcriptome analysis of D. officinale mycorrhizal symbiosis environment, low temperature stress, and phosphorus deficiency stress, this study found that only one gene was up-regulated in all three conditions. The results of this study can help understand the functions of UGT gene family in Orchidaceae plants and provide a basis for further study on the molecular regulation mechanism of polysaccharide metabolism pathway in D. officinale.

UPLC-Q-Orbitrap-MS based metabolomics and analysis of the effect of Suanzaoren Decoction on serum of chronic unpredictable mild stress depression rats / 药学学报

A UPLC-Q-Orbitrap-MS based metabolomic approach combined with biochemical assay and histopathological inspection were employed to study the intervention effects of Suanzaoren Decoction (SZRD) on chronic unpredictable mild stress (CUMS) depression rats, and to clarify the metabolic regulation pathway of SZRD. The rats were randomly divided into normal control group, CUMS model group, positive drug venlafaxine group, SZRD high (24 g·kg-1) and low (12 g·kg-1) dose groups, respectively. The CUMS model was replicated by subjecting to a variety of stimulus, such as thermal stimulation, ice water swimming, ultrasonic stimulation, tail clamping, day and night reversal, plantar electric shock and so on for rats. After oral administration of drugs for 28 days, the behavioral indexes of rats in each group were observed and the hippocampus and serum samples of rats were collected for biochemical assay and histopathological inspection. Compared with the CUMS model group, low dose and high dose SZRD groups can significantly reduce the immobility time of forced swimming (P < 0.001, P < 0.001), increase the sucrose preference rate (P < 0.01, P < 0.05), the number of crossings (P < 0.05, P < 0.01) and the number of uprights (P < 0.05, P < 0.01) in the open field test, suggesting that SZRD can significantly improve the depression-like behavior of CUMS model rats. In addition, SZRD could significantly reduce the levels of serum IL-6, IL-1β and TNF-α of CUMS model rats. A total of 21 differential metabolites in serum were identified by comparison with the data from the literature and databases. In addition, low-dose SZRD and high-dose SZRD improved the 8 and 11 perturbed potential serum biomarkers that were induced by CUMS, respectively, which related to alanine, aspartic acid and glutamic acid, tryptophan and arachidonic acid metabolism. This study provides a scientific basis for expanding the clinical indications of SZRD. This experiment was approved by the Animal Ethics Committee of Shanxi University (Approval No. SXULL2020028).

Exploring the common mechanism of Yindan Xinnaotong soft capsule in the treatment of stroke and coronary heart disease through HIF1α-MMP9-mediated HIF1α signaling pathway / 药学学报

Coronary heart disease (CHD) and stroke are the most well-known cardiovascular diseases, which share many common pathological basis. Yindan Xinnaotong soft capsule (YDXNT) is a commonly used Chinese patent medicine in the treatment of stroke and CHD. However, its action of mechanism of co-treatment for stroke and CHD is still unclear. The aim of this study was to explore the common mechanism of YDXNT in co-treatment of CHD and stroke using network pharmacology, experimental verification and molecular docking. An integrated literature mining and databases of IPA, ETCM, HERB, Swiss Target Prediction, OMIM and GeneCards were used to screen and predict active ingredients and potential targets of YDXNT in co-treatment of CHD and stroke. The protein-protein interaction network, GO analysis and pathway analysis were analyzed by IPA software. The effect of YDXNT on core targets was verified by immunofluorescence. UPLC-QTOF/MS and molecular docking were used to screen and predict the main active constituents of YDXNT and their interactions with core targets. A total of 151 potential targets are predicted for YDXNT in co-treatment of CHD and stroke. Hypoxia-inducible factor-1α (HIF1α)-matrix metalloproteinase-9 (MMP9)-mediated HIF1α signaling pathway serves as one of the common mechanisms. YDXNT could reduce the increase of mitochondrial fluorescence intensity and the protein expression of HIF1α and MMP9 in HL-1 and HA induced by oxygen and glucose deprivation/reperfusion (OGD/R) in a dose-dependent manner. Baicalin may be the material basis for treating stroke and CHD with YDXNT. In conclusion, the HIF1α signaling pathway is one of the common key mechanisms of YDXNT in the co-treatment of stroke and CHD. The study provides support and basis for the in-depth scientific connotation of the traditional Chinese medicine theory of "same treatment to different diseases".

A study on the rapidly non-destructive detection method of Huoxiang Zhengqi oral liquid using near infrared spectroscopy / 药学学报

Based on near infrared spectroscopy and high performance liquid chromatography, this paper established the regression relationship between near infrared spectroscopy and index component content of Huoxiang Zhengqi oral liquid, so as to realize the rapid detection of index component content based on near infrared spectroscopy. Magnolol, honokiol and hesperidin were used as the quality indexes of Huoxiang Zhengqi oral liquid. After using the first derivative and normalization pretreatment method, characteristic variables were screened by CARS, and the correction model was finally established by partial least-squares regression (PLSR) method. The method accuracy was evaluated with the external validation, and the prediction results were tested for significance. The results indicated that when the near infrared spectrum was scanned through the bottle, the model's correlation coefficients of prediction (Rp) were higher than 0.99, the root mean square errors of the prediction models (RMSEP) were all less than 0.008 4, and the relative standard errors of prediction set (RSEP) were all less than 2.83%. There was no significant difference in the predicted results between these two kinds of model. The models established in the non-destructive way have good performance and high prediction accuracy. The rapid and nondestructive way has application value in the quality control of Huoxiang Zhengqi oral liquid.

Different combinations of GABA, BMP7, and Activin A induced the in vitro differentiation of rat pancreatic ductal stem cells into insulin-secreting islet-like cell clusters.

AIMS: We investigated the in vitro differentiation of adult rat PDESCs into ß-like cells through supplementation of different combinations of GABA, BMP7, and Activin A in basic culture media. MATERIALS AND METHODS: The PDESCs were cultured using different inducement combinations for 28 days and microscopy, dithizone (DTZ) staining, immunohistochemical staining, real-time PCR, and glucose-stimulated insulin secretion (GSIS) assay were used to delineate the differentiation inducement potential of these combinations. KEY FINDINGS: The results show that after 28 days, the PDESCs were differentiated into ICCs containing insulin-secreting ß-like cells in different groups treated with A + B, A + G, B + G, and A + B + G but not in the control group. Upon DTZ staining the cells in ICCs were stained crimson red, demonstrating the presence of ß-like cells in ICCs and the immunohistochemistry showed the expression of Pdx1 and insulin in ICCs. Further, on 28 d the expression of Pdx1 and insulin mRNA was high in inducement groups as compared to the control group and ß-like cells in ICCs also secreted insulin and C-peptide upon glucose stimulation. Thus, the supplementation of GABA, BMP7, and Activin A in different combinations in basic culture media can induce the in vitro differentiation of PDESCs into ICCs containing ß-like cells. SIGNIFICANCE: The in vitro development of ß-like cells is a herald for cell therapy of diabetic patients and our results are a step closer towards finding the cure for diabetes.

Rapid determination of active components in Ginkgo biloba leaves by near infrared spectroscopy combined with genetic algorithm joint extreme learning machine / 中国中药杂志

Near-infrared spectroscopy(NIRS) combined with band screening method and modeling algorithm can be used to achieve the rapid and non-destructive detection of the traditional Chinese medicine(TCM) production process. This paper focused on the ginkgo leaf macroporous resin purification process, which is the key technology of Yinshen Tongluo Capsules, in order to achieve the rapid determination of quercetin, kaempferol and isorhamnetin in effluent. The abnormal spectrum was eliminated by Mahalanobis distance algorithm, and the data set was divided by the sample set partitioning method based on joint X-Y distances(SPXY). The key information bands were selected by synergy interval partial least squares(siPLS); based on that, competitive adaptive reweighted sampling(CARS), successive projections algorithm(SPA) and Monte Carlo uninformative variable(MC-UVE) were used to select wavelengths to obtain less but more critical variable data. With selected key variables as input, the quantitative analysis model was established by genetic algorithm joint extreme learning machine(GA-ELM) algorithm. The performance of the model was compared with that of partial least squares regression(PLSR). The results showed that the combination with siPLS-CARS-GA-ELM could achieve the optimal model performance with the minimum number of variables. The calibration set correlation coefficient R_c and the validation set correlation coefficient R_p of quercetin, kaempferol and isorhamnetin were all above 0.98. The root mean square error of calibration(RMSEC), the root mean square error of prediction(RMSEP) and the relative standard errors of prediction(RSEP) were 0.030 0, 0.029 2 and 8.88%, 0.041 4, 0.034 8 and 8.46%, 0.029 3, 0.027 1 and 10.10%, respectively. Compared with the PLSR me-thod, the performance of the GA-ELM model was greatly improved, which proved that NIRS combined with GA-ELM method has a great potential for rapid determination of effective components of TCM.

A preliminary pharmacophylogenetic study of Solanaceae medicinal plants containing tropane alkaloids / 中国中药杂志

The Solanaceae plants distributed in China belong to 105 species and 35 varietas of 24 genera. Some medicinal plants of Solanaceae are rich in tropane alkaloids(TAs), which have significant pharmacological activities. In this paper, the geographical distribution, chemical components, traditional therapeutic effect, pharmacological activities, and biosynthetic pathways of TAs in Solanaceous plants were summarized. Besides, the phylogeny of medicinal plants belonging to Solanaceae was visualized by network diagram. Fourteen genera of Solanaceae plants in China contain TAs and have medical records. TAs mainly exist in Datura, Anisodus, Atropa, Physochlaina, and Hyoscyamus. The TAs-containing species were mainly concentrated in Southwest China, and the content of TAs was closely related to plant distribution area and altitude. The Solanaceae plants containing TAs mainly have antispasmodic, analgesic, antiasthmatic, and antitussive effects. Modern pharmacological studies have proved the central sedative, pupil dilating, glandular secretion-inhibiting, and anti-asthma activities of TAs. These pharmacological activities provide a reasonable explanation for the traditional therapeutic efficacy of tropane drugs. In this paper, the geographical distribution, chemical components, traditional therapeutic effect, and modern pharmacological activities of TAs-containing species in Solanaceae were analyzed for the first time. Based on these data, the genetic relationship of TAs-containing Solanaceae species was preliminarily discussed, which provided a scientific basis for the basic research on TAs-containing solanaceous species and was of great significance for the development of natural medicinal plant resources containing TAs.

[New variety breeding of Dioscorea alata, cultivar "Wenshanyao No.1].

To breed a new yam cultivar of Dioscorea alata, the different and excellent germplasm resources were investigated within artificially cultivated population and some superior individuals, with a higher yield and medicinal properties, were selected. Considering results of the yield and medicinal properties during 2006-2013 cropping season, strains and lines were established and selected. As a result, the yield of the new developed cultivar (Wenshanyao No. 1, WSY01-1) reached 2217. 0 kg per 667 m2 (fresh weight) and 348.3 kg per 667 m2 (dry weight), and increased 23.8% and 23.9% comparing with control cultivars (landraces). Comparing with control cultivars, the level of polysaccharide, allantoin, and dioscin increased 36.9%, 48.3%, 20.9%, and reached 12.2%, 1.30%, 579.7 µg · g(-1), respectively. This result showed that the systematic selection method can significantly improve yield and medicinal properties of D. alata, and the developed " Wenshanyao No. 1" exhibits wide spreading prospects.

Research advances in cell models of hepatitis B virus / 临床肝胆病杂志

Hepatitis B virus (HBV) infection has become the main cause of hepatocellular carcinoma. A series of cell models for HBV infection are established to lay a good foundation for the research on the pathogenesis and treatment of HBV. In this review, we summarize culture models for a single type of cells, co-culture models for multiple types of cells, and other animal models, which are mainly for HBV transfection and infection. We also discuss the methods of cell model construction for HBV infection and their virological characteristics. It provides reliable evidence of models for scientific interpretation of advantages of traditional Chinese medicine in the prevention and treatment of chronic hepatitis B.

Application of near infrared spectroscopy combined with particle swarm optimization based least square support vactor machine to rapid quantitative analysis of Corni Fructus / 药学学报

A novel method was developed for the rapid determination of multi-indicators in corni fructus by means of near infrared (NIR) spectroscopy. Particle swarm optimization (PSO) based least squares support vector machine was investigated to increase the levels of quality control. The calibration models of moisture, extractum, morroniside and loganin were established using the PSO-LS-SVM algorithm. The performance of PSO-LS-SVM models was compared with partial least squares regression (PLSR) and back propagation artificial neural network (BP-ANN). The calibration and validation results of PSO-LS-SVM were superior to both PLS and BP-ANN. For PSO-LS-SVM models, the correlation coefficients (r) of calibrations were all above 0.942. The optimal prediction results were also achieved by PSO-LS-SVM models with the RMSEP (root mean square error of prediction) and RSEP (relative standard errors of prediction) less than 1.176 and 15.5% respectively. The results suggest that PSO-LS-SVM algorithm has a good model performance and high prediction accuracy. NIR has a potential value for rapid determination of multi-indicators in Corni Fructus.

Promotion of Function of Endothelial Progenitor Cells with Shexiang Baoxin Pill Treatment under Shear Stress / 生物医学工程学杂志

The aim of this study was to investigate whether shear stress could promote function of endothelial progenitor cells (EPCs) with Shexiang Baoxin Pill (SBP) treatment in vitro, and to study whether shear stress contributed to vascular injury repair by EPCs. EPCs were isolated and characterized; EPCs' proliferation, migration, adhesion, tube formation and eNOS protein level in vitro were investigated by culturing confluent EPCs in 4 mg/mL SBP under physiological shear stress (15 dyne/cm2) for up to 24 hours. Afterwards, EPCs were transfused into rats after wire-induced carotid artery injury augmented re-endothelialization. The results showed that, compared to the SBP group, the shear stress+SBP group obviously enhanced EPCs proliferation, migration, adhesion, tube formation and eNOS protein expression in vitro (P<0.01). After one week, immunofluorescence staining showed that endothelial regeneration rate obviously enhanced in shear stress+SBP group (P<0.01). The present study demonstrates that shear stress can promote function of endothelial progenitor cells treated with SBP, which improves the vascular injury repair potentials of EPCs.

[Breeding of new Curcuma wenyujin variety "Wenyujin No. 1"].

In order to breed and spread a new cultivar of Curcuma wenyujin, the C. wenyujin germplasm resources were investigated in authentic regions. Better varieties were chosen by comparing the yield, economic characters and quality differences between different cultivars. The results showed that the character of new selected cultivar was stable, the yield of zedoary, turmeric and curcuma was reached 313.7, 177.9, 91.2 kg per 667 m2, respectively, it increased 11.6%, 10.2%, 14.2% comparing with farmer varieties. The volatile oil contents in zedoary and turmeric was 4.0%, 3.0%, respectively. The target ingredients (germacrone) content was stable. It is demonstrated that the new cultivar "Wenyujin No. 1" has value for extension at authentic regions.

Effectiveness of cysteine proteases on protein/pigment film removal.

OBJECTIVE: Theaflavin (TF) from the black tea can react to human salivary proline-rich proteins (PRPs) to form stains on exposed dental surfaces. Here, we employed a model of protein/pigment film using TF and dephosphorylated bovine ß-casein (Dß-CN), which has an extended conformation, similar to that of salivary PRPs, on a sensor surface to assess the efficacy of cysteine proteases (CPs) including papain, stem bromelain, and ficin, on removing TF bound to Dß-CN and the control TF readsorption on the residual substrate surfaces was also measured. METHODS: The protein/pigment complex film was built by using a quartz crystal microbalance with dissipation (QCM-D). The efficacies of CPs were assessed by Boltzman equation model. The surface details were detected by grazing angle infrared spectroscopy spectra, atomic force microscopy images, and contact angles. RESULTS: The efficacy order of CPs on hydrolyzing protein/pigment complex film is ficin>papain>bromelain. The results from grazing angle infrared spectroscopy spectra, atomic force microscopy images, and contact angles demonstrated that TF bound on the Dß-CN was effectively removed by the CPs, and the amount of TF readsorption on both the residual film of the Dß-CN/TF and the Dß-CN was markedly decreased after hydrolysis. CONCLUSION: This study indicates the potential application of the CPs for tooth stain removal and suggests that these enzymes are worthy of further investigation for use in oral healthcare.

Effects of dietary inclusion of fermented cottonseed meal on growth, cecal microbial population, small intestinal morphology, and digestive enzyme activity of broilers.

Two experiments were conducted to test the feeding value of fermented cottonseed meal (FCSM) in broilers. In experiment 1, 480 1-day-old male yellow-feathered broilers were allocated into 4 dietary treatments with 6 replicates (20 birds per replicate) to examine the effects of FCSM on the growth response of chickens. Experimental feeding was performed for 6 weeks in two phases (starter, days 0 to 21; finisher, days 22 to 42). FCSM was used at 0, 40, 80, and 120 g/kg levels to replace soybean meal in the basal diet. The dietary inclusion of 40 and 80 g/kg FCSM increased (quadratic (Q): p<0.01) the body weight gain of broilers in the starter and in the overall feeding periods. Experiment 2 determined the effect of FCSM on the cecal microbial populations, intestinal morphology, and digestive enzyme activity of broilers. The number of lactobacilli in the cecal digesta increased at day 21 (p<0.01) and day 42 (linear (L): p=0.01). Coliform bacteria counts decreased (L: p<0.05) with the increasing inclusion of FCSM at day 21. The inclusion of FCSM increased (L-Q: p<0.05) villus height in the duodenum and linearly elevated (p<0.05) villus height and the villus height to crypt depth ratio in the jejunum at day 21. Similar improvement (L: p<0.05) was noted in jejunal villus height at day 42. The inclusion of FCSM improved (p<0.05) the activities of amylase and protease at day 21, as well as protease at day 42. In conclusion, the appropriate inclusion of FCSM improves growth, cecal microflora, intestinal morphology, and digestive enzyme activity in yellow-feathered broilers.

Static magnetic fields and its biomedical effects / 生物医学工程学杂志

Nowadays, health care products based on static magnetic fields (SMF) and merchandise of magnetic therapy are popular around the world. But the biomedical effects of SMF to animals or human beings remain a widely concerned controversy. In this paper, the recent researches in China and abroad about the biomedical effects of SMF were reviewed in three levels: the cellular, animal and human levels. Nevertheless, these data were not consistent with each other and even some contradicts others' researches. So, it is necessary to do more and further studies on SMF dosing regiman, sham control magnetic device and blinding procedures to obtain the optimal magnetic intensity, the desired therapeutic effects in practical cases and prepare for applying the SMF in biomedical fields more effectively in the future.

Overview of acupuncture development in Ontario Canada / 中国针灸

The history of acupuncture in Ontario, Canada was traced, and the current status as welI as the prospection were introduced in this paper. Statistics showed that the history of acupuncture in Ontario started in the 1880s, and it was only popular in China Town and Chinese community. In the 1970s, it gradually merged into the mainstream of the society, and entered into a growing period. With the tide of Chinese immigration in the 1980s and 1990s, acupuncture matured rapidly. In 2006, the "Traditional Chinese Medicine Act" was passed in Ontario, it was considered as a milestone in the history of acupuncture. At present, just like the other 23 health care professions, acupuncture has already be included into the legislation system, and become a component of Ontario's health care system. At the same time, the law and regulation may also promote the establishment of "pure Chinese Medicine" in Ontario.

Effect of Astragalus membranaceus var. mongholicus seed extracts on seed germination and seedling growth of different Codonopsis pilosula caltiver / 中国中药杂志

<p><b>OBJECTIVE</b>To reveal the allelopathy effect of Astragalus membranaceus var. mongholicus seeds and provide information for the intercrop production.</p><p><b>METHOD</b>The A. membranaceus. var. mongholicus seeds were soaked in distilled water for different time (12, 24, 36, 48, 60 h) , and then the seed extracts were used to study their effects on the seed germination, seedling growth and development of two Codonopsis pilosula.</p><p><b>RESULT</b>The A. membranaceus var. mongholicus seeds contained some allelopathy compounds. Their soaked liquid had significantly influence on the seed germination and seedling growth of C. pilosula. The seed germination rate, germination power, germination index and vigor index of two C. pilosula calrivar were improved and then inhabited with soaking time elongation. The extract soaking for 24 h significantly improved the germination traits but the extract for 60 h appeared different degrees of inhibiting vigor. The seed extracts soaking ranging between 12 and 60 h all significantly improved the above plant growth of C. pilosula but significant inhibited their radicle growth in length. And with the soaking time elongation the facilitation effect weakened and the inhibiting effect enhanced, especially more significant in the C. pilosula caltivar (Baitiaodangshen).</p><p><b>CONCLUSION</b>The A. membranaceus var. mongholicus seeds have allelopathic compounds and the endogenous inhibitor can be extracted when soaked for more than 24 h in water with intact seeds, resulting in improvement of seed germination rate. The C. pilosula could be intercropped in A. membranaceus var. mongholicus field, however, when intercroped it should notice that the intercrop proportion should vary with the caltivar.</p>

[Efficacy of Yanshu injection (a compound Chinese traditional medicine) combined with concurrent radiochemotherapy in patients with stage III nasopharyngeal carcinoma].

OBJECTIVE: To evaluate the efficacy and toxicity of Yanshu injection (a compound Chinese traditional medicine from Sophora flauescens Ait) combined with concomitant radiochemotherapy in patients with stage III nasopharyngeal carcinoma. METHODS: Sixty patients with stage III nasopharyngeal carcinoma were randomized into Yanshu group and control group (n = 30, each). Patients in the Yanshu group received Yanshu injection in addition to intensity modulated radiation therapy (IMRT) and concomitant chemotherapy, and those in the control group were treated with IMRT and concurrent chemotherapy. RESULTS: The 1-year, 2-year, 3-year and 4-year overall survival rates were 100%, 93.3%, 86.7%, 80.0% for Yanshu group, and 96.7%, 90.0%, 83.3%, 76.7% for the control group, respectively, with no significant difference between the two groups (P = 0.565). The 1-year, 2-year, 3-year and 4-year progression-free survival rates were 96.7%, 90.0%, 83.3%, 70.0% for Yanshu group, and 90.0%, 86.7%, 76.7%, 66.7% for control group, respectively, with no significant difference (P = 0.554). However, the reaction of mucosa of oral cavity, myelosuppression and thrombocytopenia in the Yanshu group were significantly lower than that in the control group (P < 0.05). The quality of life of the patients in the Yanshu group was significantly higher than that in the control group (P < 0.05). CONCLUSIONS: Yanshu injection combined with radiochemotherapy in patients with stage III nasopharyngeal carcinoma show a good efficacy and can reduce the side effects of radiochemotherapy of nasopharygeal carcinoma, and improve the quality of life of the patients.

[Adsorption kinetic study of the interaction between human salivary alpha-amylase and the polyphenoles from the black/green tea].

OBJECTIVE: To explore the driving force of the oral astringency produced by the interaction of theaflavin (TF) and epigallocatechin-3-gallate (EGCG) to human salivary a-amylase(HSA). METHODS: The constants of the rate, equilibrium of reaction (k(a), k(d), K(A), and K(D)) and Langmuir, Freundlich adsorption isotherm (K(L), K(f), and Mm) were determined by surface plasmon resonance (SPR) technique and adsorption kinetics. RESULTS: Both of Langmuir and Freundlich models could be used for describing the binding processes of TF and EGCG onto HSA surfaces, and there were no significant differences of the correlation coefficient of determination between these two models (P > 0.05). The constants of adsorption isotherm, the rate and equilibrium constants of the association for TF were higher than those of EGCG (P < 0.05). The rate and equilibrium constants of the dissociation for TF were lower than those of EGCG (P < 0.05). The affinity of TF to HSA was higher than that of EGCG. CONCLUSION: The sorely oral astringency is much easily produced by TF from the black tea rather than EGCG from the green tea. The driving force of the oral astringency is attributed to the hydrogen bonds of hydroxyl groups and hydrophobic interaction of galloyl groups in polyphenolic structures.

Adsorption kinetic study of the interaction between human salivary alpha-amylase and the polyphenoles from the black/green tea / 华西口腔医学杂志

<p><b>OBJECTIVE</b>To explore the driving force of the oral astringency produced by the interaction of theaflavin (TF) and epigallocatechin-3-gallate (EGCG) to human salivary a-amylase(HSA).</p><p><b>METHODS</b>The constants of the rate, equilibrium of reaction (k(a), k(d), K(A), and K(D)) and Langmuir, Freundlich adsorption isotherm (K(L), K(f), and Mm) were determined by surface plasmon resonance (SPR) technique and adsorption kinetics.</p><p><b>RESULTS</b>Both of Langmuir and Freundlich models could be used for describing the binding processes of TF and EGCG onto HSA surfaces, and there were no significant differences of the correlation coefficient of determination between these two models (P > 0.05). The constants of adsorption isotherm, the rate and equilibrium constants of the association for TF were higher than those of EGCG (P < 0.05). The rate and equilibrium constants of the dissociation for TF were lower than those of EGCG (P < 0.05). The affinity of TF to HSA was higher than that of EGCG.</p><p><b>CONCLUSION</b>The sorely oral astringency is much easily produced by TF from the black tea rather than EGCG from the green tea. The driving force of the oral astringency is attributed to the hydrogen bonds of hydroxyl groups and hydrophobic interaction of galloyl groups in polyphenolic structures.</p>