Microbial synthesis of plant polyphenols / 生物工程学报

Plant polyphenols are phenylpropanoid derivatives including phenolic acids, stilbenes, curcumins and flavonoids. These compounds display a variety of biological and pharmacological activities such as antioxidation, vasorelaxation, anti-coagulation, anti-inflammation, anti-tumor and anti-virus, conferring a huge application potential in the sectors of drugs, foods, cosmetics, and chemicals. Microorganisms have become important hosts for heterologous synthesis of natural products due to the advantages of fast growth, easiness of culture and industrial operation. In recent years, the development of synthetic biology has boosted the microbial synthesis of plant natural products, achieving substantial progress. In this review, we summarize the synthesis of plant polyphenols in engineered Escherichia coli, Saccharomyces cerevisiae and other microorganisms equipped with the designed biosynthetic pathways of polyphenols. We also discuss the optimization strategies such as precursor engineering, dynamic regulation, and co-cultivation to improve the production of polyphenols and propose future prospects for polyphenol pathway engineering.

Main chemical constituents in aerial parts of Glycyrrhiza uralensis by UPLC-Q-Exactive Orbitrap-MS / 中国中药杂志

Chemical constituents from aerial parts of Glycyrrhiza uralensis were analyzed and identified using ultra-high performance liquid chromatography coupled with hybrid quadrupole-orbitrap mass spectrometry(UPLC-Q-Exactive Orbitrap-MS). The chromatographic column of Waters Acquity UPLC BEH-C_(18)(2.1 mm×100 mm, 1.7 μm) was adopted, with acetonitrile-water(0.5% formic acid) as mobile phase at a flow rate of 0.2 mL·min~(-1). Data was collected in positive and negative modes of electrospray ionization(ESI). A total of 55 compounds, including 42 flavonoids, 9 stilbenes, 2 coumarins, 1 lignin and 1 phenolic acid, which were characterized in the aerial parts of G. uralensis based on accurate molecular mass information of molecular and product ions provided by UPLC-Q-Exactive Orbitrap-MS based on comparison with standard substances and references. It is an effective and accurate method to provide chemical information of constituents in aerial parts of G. uralensis, and can provide a reference for further study on pharmacodynamic material basis and resources development and utilization.

Sorting and cryopreservation of goat sperm with or without phenolic compounds / Seleção e criopreservação de espermatozoides caprinos com ou sem compostos fenólicos

The objectives of this study were to evaluate goat sperm sorting in continuous Percoll® density gradients and gamete freezability, in the presence or absence of phenolic antioxidants. For this, semen pools were sorted, frozen, and evaluated. The non-selected group (NSg) presented lower progressive motility (PM), linearity (LIN), straightness (STR), and wobble (WOB) than the selected groups, and straight line velocity (VSL) compared to those with catechin or resveratrol. The amplitude of lateral head displacement (ALH) was higher in NSg, and quercetin reduced the mitochondrial membrane potential (MMP). After thawing, the NSg presented lower PM than the selected groups, VSL and VAP (average path velocity) than the selected group with or without catechin, LIN and WOB than the selected with or without catechin or resveratrol, and STR than the selected with catechin. Moreover, NSg presented higher ALH and BCF than the samples selected with or without catechin. Plasma membrane integrity and intact and living cells were higher in the selected groups, and MMP was lower in the NSg and the selected group with quercetin. Thus, centrifugation in Percoll® continuous density gradients is a viable methodology to select goat sperm compatible with the freezing, especially in the presence of catechin or resveratrol.(AU)

Objetivou-se avaliar a separação de espermatozoides caprinos em gradientes de densidade contínuos de Percoll® e a congelabilidade espermática, com ou sem antioxidantes fenólicos. Para tal, pools seminais foram selecionados, congelados e avaliados. O grupo não selecionado (gNS) apresentou menor motilidade progressiva (MP), linearidade (LIN), retilinearidade (STR) e oscilação (WOB) do que os selecionados, bem como menor velocidade linear progressiva (VSL) do que os com catequina ou resveratrol. A amplitude de deslocamento lateral de cabeça (ALH) foi maior no gNS e a quercetina reduziu o potencial de membrana mitocondrial (PMM). Após a descongelação, o gNS manifestou menor MP do que os selecionados, menor VSL e VAP (velocidade média da trajetória) do que os com ou sem catequina, menor LIN e WOB do que os com ou sem catequina ou resveratrol, e menor STR do que os com catequina, além de maior ALH e BCF do que os com ou sem catequina. A integridade da membrana plasmática e as células intactas e vivas foram maiores nas amostras selecionadas e o PMM foi inferior no gNS e no selecionado com quercetina. Portanto, a centrifugação em gradientes contínuos de densidade de Percoll® é uma metodologia viável para selecionar espermatozoides caprinos compatíveis com a congelação, especialmente na presença de catequina ou resveratrol.(AU)

Simultaneous rapid detection of ten stilbenes in serum of mice by UPLC-MS/MS / 中国中药杂志

Stilbenes is a class of natural polyphenols with 1,2-diphenylethylene as the skeleton structure which have structural and active diversity. However, there are fewer studies on their metabolic process, which limits the in-depth research and development of such components. An UPLC-MS/MS method simultaneously determining contents of ten stilbenes was firstly established in this study and applied to study the ten stilbenes of peony seed coats in the serum of C57 mice.Piceatannol was the internal standard, and methanol was used for protein precipitation, UPLC-MS/MS with negative ion mode was used for analysis, and the method was validated.The serum samples were collected and detected after mice being oral administered with 800 mg·kg~(-1) peony seed coat extracts for 8 weeks. The results showed that suffruticosol A, suffruticosol B, suffruticosol C, trans-ε-viniferin, cis-gnetin H, trans-suffruticosol D and trans-gnetin H were detected in serum samples, and the highest is suffruticosol A. The method is simple and quick with high specificity and sensitivity, and it is suitable for quantitative determination of ten stilbenes in the serum of mice.

Research progress on chemical composition and pharmacological effects of Rhei Radix et Rhizoma and predictive analysis on quality markers / 中草药

Rhei Radix et Rhizoma is a kind of traditional Chinese medicinal material in China, which has unique efficacy and rich resources. It is mainly distributed in the alpine mountains of temperate and subtropical Asia. Its genuine producing areas are Gansu Province, Qinghai Province, Sichuan Province, and Tibet Autonomous Region. In recent years, with the continuous in-depth study of Radix et Rhizoma by scholars at home and abroad, many kinds of chemical constituents, extensive pharmacological effects and application and development of Radix et Rhizoma have attracted much attention, and have broad application prospects and considerable market value. Based on the analysis of its chemical composition and traditional efficacy combined with modern pharmacological action, and according to the theory of quality marker, the quality markers of Radix et Rhizoma were predicted and analyzed from the aspects of the chemical composition and traditional medicinal properties, traditional efficacy, new clinical uses, plasma composition, measurable components, effective components in different compatibility, and the effect of storage time and so on, which provides a scientific basis for the quality evaluation of Radix et Rhizoma and establishment of its quality control system.

Prenylated stilbenes and flavonoids from the leaves of Cajanus cajan / 中国天然药物

Three new prenylated stilbenes, named as cajanusins A-C (1-3), and one new natural product cajanusin D (4), along with six known derivatives (5-10) were isolated from the leaves of Cajanus cajan. Their structures were fully elucidated by means of extensive spectroscopic methods and comparison with data in the reported literatures. The new compounds of 1 and 2 were evaluated for in vitro cytotoxic activities against a panel of human cancer cell lines.

Protective effects of stilbene glycoside on 1-methyl-4-phenyl-1,2, 3,6-tetrahydropyridine induced mice model of Parkinson's disease / 中华老年医学杂志

Objective To investigate the protective effects of stilbene glycoside(2,3,5,4'-tetrahydroxy-stilbene-2-O-β-D-glucoside,TSG) on 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP)-induced mice model of Parkinson's disease(PD).Methods Mice were randomly divided into the blank control group,the negative control group,the TSG high-dose group,the TSG low-dose group and the positive drug group(n=20 each).Mice were weighted daily to observe the changes of body weight,and mice motor and behavior function were tested by open field test.Level changes of α/β synuclein in brain cortex,cerebellum,midbrain,and hippocampal were detected by Western blot.Results Compared with the blank control group,the negative control group showed that the body weight was decreased (P ＜ 0.05).Compared with the negative control group,the body weight was increased in the TSG high-and low-dose groups and the positive drug group (P ＜ 0.05).The spontaneous behavior was impaired in the negative control group.Compared with the blank control group,the negative control group showed that the open field test showed traveled distance over a 10-min period was significantly shortened at 1 st,7th,28th days after testing(all P＜0.05).The trajectory of motor axons indicated that mice in the negative control group showed dyskinesia,but the groups of positive drug and high-and low-dose of TSG could reverse this dyskinesia.Compared with the blank control group,brain α/β synuclein protein levels were increased in the negative control group,and decreased in positive drug and TSG high-and low-dose groups (P ＜0.05).Conclusions Stilbene glycosides exert neuroprotective effects in MPTP-induced mice model of PD.

Increasing pinosylvin production in Escherichia coli by reducing the expression level of the gene fabI-encoded enoyl-acyl carrier protein reductase

Background: The plant secondary metabolite pinosylvin is a polyphenol from the stilbene family, which have positive effects on human health. Biotechnological production is an attractive alternative for obtaining this stilbene. In Escherichia coli, malonyl-CoA is the precursor for both stilbene and fatty acid syntheses. In this study, with the aim of increasing pinosylvin production, we evaluated a novel approach that is based on reducing the expression of the gene fabI, which encodes the enzyme enoyl-acyl carrier protein reductase that is involved in fatty acid synthesis. Results: A recombineering method was employed to eliminate the chromosomal -35 promoter sequence and the upstream region of the gene fabI in E. coli strain W3110. Analysis, employing RT-qPCR, showed that such modification caused a 60% reduction in the fabI transcript level in the mutant strain W3110Δ-35fabI::Cm compared to the wild type W3110. Synthetic genes encoding a mutant version of 4-coumaroyl-CoA ligase from Streptomyces coelicolor A3 with improved catalytic activity employing cinnamic acid as substrate and a stilbene synthase from Vitis vinifera were cloned to generate the plasmid pTrc-Sc4CL(M)-VvSTS. The production performance of strains W3110Δ-35fabI::Cm/pTrc-Sc4CL(M)-VvSTS and W3110/pTrc-Sc4CL(M)- VvSTS was determined in shake flask cultures with Luria-Bertani medium supplemented with 10 g/L glycerol and 3 mM cinnamic acid. Under these conditions, the strain W3110Δ-35fabI::Cm/pTrc-Sc4CL(M)-VvSTS produced 52.67 mg/L pinosylvin, a level 1.5-fold higher than that observed with W3110/pTrc-Sc4CL(M)-VvSTS. Conclusion: A reduction in the transcript level of fabI caused by the elimination of the -35 and upstream promoter sequences is a successful strategy to improve pinosylvin production in E. coli.

Effect of Resveratrol on Oral Cancer Cell Invasion Induced by Lysophosphatidic Acid / 치위생과학회지

The aim of the current study was to demonstrate the potential therapeutic efficacy of resveratrol in oral cancer patients. Lysophosphatidic acid (LPA) intensifies cancer cell invasion and metastasis, whereas resveratrol, a natural polyphenolic compound, possesses antitumor activity, suppressing cell proliferation and progression in various cancer cell lines (ovarian, gastric, oral, pancreatic, colon, and prostate cancer cells). In addition, resveratrol has been identified as an inhibitor of LPA-induced proteolytic enzyme expression and ovarian cancer invasion. Furthermore, resveratrol was shown to inhibit oral cancer cell invasion by downregulating hypoxia-inducible factor 1α and vascular endothelial growth factor expression. Recently, we demonstrated that LPA is important for the expression of transcription factors TWIST and SLUG during epithelial-mesenchymal transition (EMT) in oral squamous carcinoma cells. In this study, we treated serum-starved cultures of oral squamous carcinoma cell line YD-10B with resveratrol for 24 hours prior to stimulation with LPA. To identify an optimal resveratrol concentration that does not induce apoptosis in oral squamous carcinoma cells, we determined the toxicity of resveratrol in YD-10B cells by assessing their viability using the MTT assay. Another assay was performed using Matrigel-coated cell culture inserts to detect oral cancer cell invasion activity. Immunoblotting was applied for analyzing protein expression of SLUG, TWIST1, E-cadherin, and GAPDH. We demonstrated that resveratrol efficiently inhibited LPA-induced oral cancer cell EMT and invasion by downregulating SLUG and TWIST1 expression. Therefore, resveratrol may potentially reduce oral squamous carcinoma cell invasion and metastasis in oral cancer patients, improving their survival outcomes. In summary, we identified new targets for the development of therapies against oral cancer progression and characterized the therapeutic potential of resveratrol for the treatment of oral cancer patients.

High temperature and UV-C treatments affect stilbenoid accumulation and related gene expression levels in Gnetum parvifolium

Background: Gnetum parvifolium stems and roots have been used for a long time in traditional Chinese medicines. Stilbenes are bioactive compounds present in G. parvifolium plants, and they possess antioxidative and anticancer properties. However, little is known about the responses of G. parvifolium stilbene biosynthetic pathways to stress conditions. Therefore, we investigated stilbene biosynthesis, including the expression of relevant genes, in G. parvifolium exposed to high-temperature and ultraviolet-C treatments. Results: High temperatures did not influence the accumulation of total stilbenes in stems but decreased stilbene concentrations in roots at 3 h, with a subsequent restoration to control levels. In contrast, ultraviolet irradiation induced the accumulation of total stilbenes in stems but not in roots. We also observed that high temperatures inhibited the production of resveratrol and piceatannol in G. parvifolium stems and roots, whereas ultraviolet treatments initially inhibited their accumulation (up to 6 h) but induced their production at later time points. Analyses of specific genes (i.e., PAL, C4H, 4CL, STS, and CYP) revealed that their expression levels generally increased in stress-treated stems and roots, although there was some variability in the expression profiles during treatments. Conclusions: Our results indicated that high temperatures and ultraviolet irradiation differentially affect the biosynthesis of specific stilbenes in G. parvifolium stems and roots. Therefore, cultivating G. parvifolium seedlings under optimal stress conditions may increase the biosynthesis of specific stilbene compounds.

Simultaneous determination of thirteen components in Polygoni Multifori Caulis by UPLC-MS/MS / 中国中药杂志

A comprehensive analytical method based on UPLC-MS/MS was developed for the simultaneous determination of thirteen components including three stilbenes (stilbeneglucoside, polydatin, resveratrol), four anthraquinones (emodin, physcion, emodin-8-β-D-glucopyranoside, aloe-emodin), five flavonoids (epicatechin, rutin, hyperoside, astragalin,quercetin) and one phenolic acid (gallic acid) in Polygoni Multifori Caulis.The separation was carried out on a Waters BEH C18 column（2.1 mm×100 mm,1.7 μm）with gradient elution of acetonitrile-water (0.1% acetic acid) at a flow rate of 0.25 mL•min⁻¹, and column temperature was 35 ℃. The target compounds were analyzed by multiple reaction monitoring (MRM) mode. TOPSIS analysis ware performed to evaluate the samples from different areas and commercial herbs according to the contents of thirteen components. The correlation coefficients of all the calibration curves were higher than 0.991 5. The average recoveries ranged from 95.24% to 102.3%, and the relative standard deviations were less than 5%. The result of TOPSIS analysis showed that the comprehensive quality of Polygoni Multifori Caulis sample from Guangzhou was better. The developed method with good repeatability and accuracy was suitable for the simultaneous determination of multiple functional substances, which provided a new basis for the comprehensive assessment and overall control of the quality of Polygoni Multifori Caulis.

Determination of ten stilbenes and their antioxidant activity of peony seed coat, seed kernel and seed coat extracts / 中国中药杂志

The seed of tree peony and herbaceous peony contained a variety of stilbenes which possess many pharmacological activities, such as antitumor, anti-inflammatory, allergy and neuraminidase inhibition. In order to develop and use peony seed resources, a simple and sensitive HPLC-DAD was developed for simultaneous determination of 10 stilbenes in peony samples, i.e.,suffruticosol A,suffruticosol B,suffruticosol C,trans-resveratrol,cis-ε-viniferin,trans-ε-viniferin,cis-suffruticosol D,cis-gnetin H,trans-suffruticosol D and trans-gnetin H. At the same time, the scavenging activity of DPPH free radicals was employed to evaluate their antioxidant effect. The results showed that the 10 stilbenes are mainly present in peony seed coat (total content of more than 16.7%) compared to peony seed kernel (total content less than 0.3%), and can be enriched in the extract of peony seed coat (total content of more than 75%) The extract of peony seed coat and 10 stilbenes exhibited significant antioxidant properties. This work provides a foundation for comprehensive utilization of the tree peony and herbaceous peony seed resources.

Resveratrol protects oxygen-glucose deprivation rat cortical neurons by regulating SIRT1/AMPK signaling pathways / 国际脑血管病杂志

Objective To investigate the effects of resveratrol on the first and double oxygen-glucose deprivation (OGD) primary cortical neuron silent information regulator 1 (SIRT1), AMP-activated protein kinase (AMPK) activity and ATP content, and its possible neuroprotective mechanism. Methods Cortical neurons were taken from the embryos of 18-day Wistar rats. An in vitro repeated ischemia model was induced by the double OGD after the success of primary culture. Trypan blue stalning was used to detect the cel survival rate. Western blot was used to detect the SIRT1 and phospho-AMPK expression. Deacetylase fluorescence assay was used to detect the SIRT1 activity. Bioluminescence assay was used to detect the ATP content. Results Compared with the control group, resveratrol (0. 5 μmol/L) preconditioning significantly increased the survival rates after the single and double OGD (al P < 0. 001), ATP content (al P = 0. 004), SIRT1 activity (single: P = 0. 001; double: P = 0. 002), and the expression levels of SIRT1 (single: P = 0. 029; double: P = 0. 023) and phospho-AMPK (al P = 0. 001). Conclusions Resveratrol has the neuroprotective effect for the first and double OGD cortical neurons. Its mechanism may be associated with upregulating the SIRT1/AMPK signaling pathways and decreasing the energy requirements.

Neuroprotection of Stilbenes from Leaves of Cajanus cajan against Oxidative Damage Induced by Corticosterone and Glutamate in Differentiated PC12 Cells / 中草药·英文版

Objective: To investigate the neuroprotective effects of four stilbenes, namely cajaninstilbene acid (CSA), longistyline A, longistyline C, and cajanolactone A, isolated from the leaves of Cajanus cajan. Methods: Neuroprotective effects of the four stilbenes were evaluated using rat pheochromocytoma cell line (PC12 cells) damage models induced by corticosterone (Cort) or glutamate. In order to elaborate whether the neuroprotective effects of stilbenes are related to anti-oxidant properties, both oxidant and anti-oxidant parameters were measured. Results: The results of MTT assay and LDH release assay demonstrated that the four stilbenes possessed neuroprotective effects. Moreover, the treatment on PC12 cells with Cort or glutamate (Glu) could significantly increase the levels of ROS and MDA with decreasing the activities of SOD and CAT. However, the four tested stilbenes could significantly alleviate such situation by dropping out the levels of ROS and MDA, as well as enhancing the activities of SOD and CAT. Conclusion: These results provide a scientific basis for further studies to explore the potential neuroprotective effects on neurodegenerative diseases.

Advances in research of chemical constituents and pharmacological activites of Cercis Linn / 中国药学杂志

METHODS: Literatures of experimental study on Cercis Linn, at home and abroad were consulted and summarized.

Neuroprotective mechanisms of resveratrol in cerebral ischemia / 国际脑血管病杂志

Resveratrol is a polyphenol phytoalexin presents in a variety of plant species.Many studies have shown that resveratrol exerts neuroprotective effects.This article reviewes the neuroprotective mechanisms of resveratrol in cerebral ischemia from the aspects of antiapoptosis,antioxidant and antiinflammatory.

Plant derived anticancer agents: A review.

Cancer is a major public health burden in both developed and developing countries. Plant-derived compounds have been an important source of several clinically useful anti-cancer agents including taxol, vinblastine, vincristine, the camptothecin derivatives, topotecan and irinotecan, and etoposide derived from epipodophyllotoxin are in clinical use all over the world. About 30 plant derived compounds have been isolated so far and are currently under clinical trials. Cancer chemopreventive agents, many of which are natural products, are capable of preventing or inhibiting the process of carcinogenesis. As with other pharmaceutical agents useful for disease prevention, a pharmacoeconomic analysis of a cancer chemopreventive formulation would need to be considered, and the composition of the formulation should improve over time. A number of promising new agents are in clinical development based on selective activity against cancer-related molecular targets, including flavopiridol, roscovitine, combretastatin A-4 phosphate , betulinic acid and silvestrol are in clinical or preclinical development.

Expression of autophagy-associated protein induced by β-amyloid and effect of tetrahydroxy stilbene glucoside on it in hippocampus / 中华神经科杂志

Objective To observe the effect of tetrahydroxy stilbene glucoside (TSG) on the behavior on rat model and the expressions of autophagy-associated protein Beclin-1 and LC3- Ⅱ induced by Aβ1-42 Methods Eighty rats were equally randomized into 4 groups (n =20):The control group,the sham operated group,the model group and the TSG group.The behavior of rats was measured by using Y-maze and Morris water maze.The expression of Beclin-1 and LC3- Ⅱ in rats hippocampus was detected by Western blot and RT-PCR at the time points.Results The number of electric-stimulus in hippocampus significantly increased and the Morris water maze test showed that the escape latency prolonged,swimming distance increased and the times of crossing the exact former platform location decreased both in the model and TSG groups after 21 days compared with those in control group.The mRNAs and protein expressions of Beclin-1 (0.51 ±0.03)and LC3-Ⅱ (0.68 ± 0.04) in model group were higher than that in control group (0.31 ± 0.01,0.31 ± 0.02) at that time point ( Beclin-1:t =28.2843,P ＜ 0.05 ; LC3- Ⅱ :t =37.0000,P ＜0.05).Compared to model group,the expression of the Beclin-1 and LC3- Ⅱ was decreased at 21 d in TSG group (Beclin-1:t =9.8387,P ＜ 0.05 ; LC3- Ⅱ :t =16.2698,P ＜ 0.05 ).Conclusions Autophagy self-regulated system is started through the increased expressions of Beclin-1 and LC3- Ⅱ after Aβ deposition in rats,so as to attenuate cerebral injury caused by Aβ neurotoxicity.Autophagy pathway is possible one of the mechanisms in Aβ neurotoxic injury. Tetrahydroxy stilbene glucoside from polygonum multiflorum has protective effect on it.

Resveratrol neuroprotection in cerebral ischemia / 国际脑血管病杂志

Resveratrol is a polyphenolic compounds in many plants.It has many effects inchuding antioxidation,anti-inflammation,inhibiting apoptosis,and scavenging free radicals.Resveratrol preconditioning has neuroprotective effect in ischemia-reperfusion in rats by activating silent information regulator 2 homolog 1.This effect is similar to brain ischemic preconditioning.In addition,resveratrol can also attenuate the brain infraction volume of cerebral ischemia/reperfusion in mice and improve neurological function.This article reviews the neuroprotective effect of resveratrol and its mechanisms in cerebral ischemia.

Chemical constituents from rhizome of Matteuccia orientalis / 中草药

Objective: To study the chemical constituents from 60% ethanol extract of the rhizomes of Matteuccia orientalis. Methods: Chromatographic methods were used for the isolation and purification. Structures were identified on the basis of spectroscopic analysis. Results: Eleven compounds were isolated from M. orientalis and identified as (±)-thunberginol C (1), (2S)-5, 7, 3′, 5′-tetrahydroxyflavanone (2), naringenin (3), strobopinin (4), farrerol (5), leptorumol (6), cis-3, 5-dihydroxystilbene (7), dihydropinosylvin (8), paeonol (9), 3, 4-dihydroxybenzalacetone (10), and caffeic acid methyl ester (11). Conclusion: Compounds 1-11 are isolated from the plants of Matteuccia Todaro for the first time.