The Effect of Uncaria gambir on Optical Properties and Thermal Stability of CNF/PVA Biocomposite Films

Cellulose-based film has gained popularity as an alternative to synthetic polymers due to its outstanding properties.Among all types of cellulose materials available,cellulose nanofiber(CNF)has great potential to be utilized in a diverse range of applications,including as a film material.In this study,CNF biocomposite film was prepared by using polyvinyl alcohol(PVA)as a matrix and Uncaria gambir extract as a filler.This study aims to investigate the effect of Uncaria gambir extract on the optical properties and thermal stability of the produced film.The formation of the CNF biocomposite films was confirmed using Fourier Transform Infrared Spectroscopy,their transmittance characteristics were measured using UV-Vis spectroscopy and a transmittance meter,while their reflectance was determined using a reflectance meter.The results revealed that the addition of Uncaria gambir extract to the CNF biocomposite film improved its UV-shielding properties,as indicated by the lower percentage of transmittance in the visible region,10%–70%.In addition,its reflectance increased to 10.6%compared to the CNF film without the addition of Uncaria gambir extract.Furthermore,the thermal stability of the CNF biocomposite film with the addition of Uncaria gambir extract improved to around 400℃–500℃.In conclusion,the results showed that CNF biocomposite film prepared by adding Uncaria gambir extract can be a promising candidate for optical and thermal management materials.

Uncarialines A-E,new alkaloids from Uncaria rhynchophylla and their anticoagulant activity

Uncarialines A-E(1-5),five undescribed monoterpene indole alkaloids,together with five known analogues were obtained from the stems of Uncaria rhynchophylla.Alkaloids 1-3 were unique 3,4-seco-tricyclic alkaloids with a 6/5/10 ring system,while 4 and 5 possessed a rare rearranged scaffold originated from corynantheine-type alkaloids with C-2/C-7 oxidation.Their structures were characterized by a comprehensive analysis of MS,NMR,and ECD.Their effects on blood clotting times of human plasma were evaluated and alkaloid 5 had a slight prolongation effect on both thrombin time and activated partial thromboplastin time(p<0.001).

Rapid Analysis of Four Alkaloids in Uncaria rhynchophylla by Core-Shell Column HPLC and Quantitative Analysis of Multi-Components by Single Marker(QAMS)

As a traditional herbal medicine,the major alkaloids in Uncaria rhynchophylla have been proven to have blood pressure-lowering and sedative effects.It is essential to develop an effective method for the determination of the major alkaloids in U.rhynchophylla.In this research,a rapid quantitative analysis involving multi-components analysis by a single marker strategy coupled with core-shell column HPLC was adopted to analyse four alkaloids(corynoxeine,isocorynoxeine,isorhynchophylline,rhynchophylline)in U.rhynchophylla.Isorhynchophylline was selected as the internal reference substance,the content of which was determined by the traditional external standard method.Relative correction factors(RCF)between isorhynchophylline and the other three alkaloids were calculated respectively.The results showed that the QAMS method had good robustness under different HPLC instruments.Nineteen batches of U.rhynchophylla were tested.No significant difference was observed between the results by QAMS and EMS(Correlation coefficient>0.99,p>0.05).The QAMS method could be employed as a rapid,effective technique for the quality control of U.rhynchophylla.

Synergistic effect of pinellia total alkaloids and uncaria total alkaloids on anticonvulsant action in mice and rats

Aim To investigate the synergistic effect of the combination of pinellia total alkaloid （PTA） and uncaria total alkaloid （UTA）, and explore the mechanism of anticonvulsant action. Methods Anticonvulsant and toxic effect profiles of combinations of PTA with UTA, alone and at three fixed ratios of 1：4, 1 ：1, 4：1, were evaluated in maximal electroshock （MES）-induced seizures and acute toxicity test in mice. Respective ED50 and LD50 were calculated with Bliss＇s method. Their synergistic effect were evaluated by isobolographic analysis and allowed the determination of benefit indices （BI） for respective combinations. The model of convulsive rats kindled by penicillin topically injected into cortex was used to investigated the content of Glu, Asp, Gly and GABA in hippocampus using high performance liquid chromatography （HPLC）. Results Combinations of PTA and UTA at the ratio of 4：1 were synergistic in MES test and antagonistic in acute toxicity test, showing the best profile for combinations of PTA with UTA. In contrast, the ratios of 1 ：4 and 1 ： 1, despite synergistic in MES test, were additive in acute toxicity test. The 4：1 combination and two drugs alone significantly decreased Glu level and increased GABA level in the hippocampus, but the GABA level in the 4：1 combination group was higher than that in the two drugs alone groups. They did not have significant influence on the levels of ASp and Gly. Conclusion Combinations of PTA and UTA at 4：1 ratio demonstrated synergistic effect in anticonvulsant action and antagonistic effect in toxicity. The anticonvulsant mechanism might be related to decreasing the excitability of Glutamatergic neurons and increasing the inhibition of GABAergic neurons.

Study on Germination Rate of Uncaria rhynchophylla (Miq.) Jacks

[Object] The research aimed to find out seed germination conditions and regulations.[Method] Seeds were soaked by clear water and 4 chemical agents of different concentrations(NaHCO3,KHCO3,K2CO3,NaClO)then conducted germination test in illumination box.[Result] Seed germination number and absolute germination rate(above 80%)in water treatment group was obviously higher than other treatments.[Conclusion] No dormancy phenomenon in mature embryo and no inhibition in seed coat,so conventional moist treatment can induct seed germination.

UFLC‑PDA‑MS/MS Profling of Seven Uncaria Species Integrated with Melatonin/5‑Hydroxytryptamine Receptors Agonistic Assay

Uncariae Ramulus Cum Uncis(Gou-Teng),the dried hook-bearing stems of several Uncaria plants(Rubiaceae),is a wellknown herbal medicine in China.The clinical application of Gou-Teng is bewildered for the morphological and chemical similarity between diferent species.In order to discern their chemical and biological diference,an ultra-fast liquid chromatography equipped with ion trap time-of-fight mass spectrometry(UFLC-IT/TOF-MS)combining with melatonin(MT1 and MT2)and 5-hydroxytryptamine(5-HT1A and 5-HT2C)receptors agonistic assay in vitro was conducted on seven Uncaria species.As a result,57 compounds including 35 indole alkaloids,ten favonoids,fve triterpenoids,fve chlorogenic analogues,and two other compounds were characterized based on their MS/MS patterns and UV absorptions.Specifcally,cadambine-type and corynanthein-type alkaloids were exclusively present in U.rhynchophylla and U.scandens,whereas corynoxine-type alkaloids were commonly detected in all the seven Uncaria plants.Three Uncaria species,U.rhynchophylla,U.macrophylla,and U.yunnanensis showed obviously agnostic activity on four neurotransmitter receptors(MT1,MT2,5-HT1A,and 5-HT_(2C)).This frst-time UFLCMS-IT-TOF analyses integrated with biological assay on seven Uncaria plants will provide scientifc viewpoints for the clinical application of Gou-Teng.

Indole Alkaloids Inhibiting Neural Stem Cell from Uncaria rhynchophylla

Uncaria rhynchophylla is commonly recognized as a traditional treatment for dizziness,cerebrovascular diseases,and nervous disorders in China.Previously,the neuro-protective activities of the alkaloids from U.rhynchophylla were intensively reported.In current work,three new indole alkaloids(1–3),identified as geissoschizic acid(1),geissoschizic acid N4-oxide(2),and 3b-sitsirikine N4-oxide(3),as well as 26 known analogues were isolated from U.rhynchophylla.However,in the neural stem cells(NSCs)proliferation assay for all isolated compounds,geissoschizic acid(1),geissoschizic acid N4-oxide(2),isocorynoxeine(6),isorhynchophylline(7),(4S)-akuammigine N-oxide(8),and(4S)-rhynchophylline N-oxide(10)showed unexpected inhibitory activities at 10 μM.Unlike previous neuro-protective reports,as a warning or caution,our finding showcased a clue for possible NSCs toxicity and the neural lesions risk of U.rhynchophylla,while the structure–activity relationships of the isolated compounds were discussed also.

ISORHYNCHOPHYLLIC ACID,A NEW AIKALOID FROM UNCARIA SINENSIS

From the hook of Uncaria sinensis, a new alkaloid, isorhynchophyllic acid was isolated and its structure was elucidated by spectral data and chemical reaction.

Cryopreservation of Cat’s Claw (<i>Uncaria tomentosa</i>)

Uncaria tomentosa presents tomentum that resembles cat’s claws, hence its common name, is a plant that produces various secondary metabolites that are traditionally used in alternative medicine. The natural distribution of this species has been affected by indiscriminate harvesting from its habitat. In the present research, cryopreservation (liquid nitrogen, LN, -196&degC) was evaluated as an option for ex situ conservation of this species. The following techniques were evaluated: vitrification and encapsulation-dehydration of apices, vitrification of cell suspensions, and seed desiccation and vitrification. Preculture conditions and exposure times to LS and PVS2 were evaluated. Apex survival was the highest (82%) with preculture in 0.25 M sucrose followed by incubation for 20 and 30 min in LS and PVS2, respectively, prior to cooling in LN. The encapsulation-dehydration technique was evaluated by using sucrose preculture and different capsule moisture contents. Survival of apices cooled in LN was not significantly different between treatments and varied from 31.8% to 52.9% for capsule moisture contents between 22.7% and 20.3%. For cell suspensions precultured in 0.5 M sucrose, cell multiplication and formation of calli with very good appearance were observed in 61.1% of the cultures following vitrification. For cryopreservation of seeds, germination was 89.5% using the desiccation technique and 67.6% to78.1% using vitrification.

Pseudotargeted metabolomics for exploring the changes of neurotransmitters profile in aging rat brain and the potential neuroprotective effect of alkaloids from Uncaria rhynchophylla

Background:Aging is an essential risk factor for most neurodegenerative diseases,including Alzheimer’s disease and Parkinson’s disease.However,changes in the levels of neurotransmitters that are associated with aging are not well understood.Methods:Methods such as liquid-liquid extraction,protein precipitation,and solid-phase extraction,using 20 different extraction solvents,were evaluated to optimize the extraction of neurotransmitters.A pseudotargeted metabolomics approach was developed to detect neurotransmitters in brain tissues using ultra-high-performance liquid chromatography coupled with tandem triple quadrupole mass spectrometry.Alkaloids that crossed into the brain were used to evaluate the effect of glutamic acid-induced excitatory neurotoxicity in SH-SY5Y cells.Results:The overall extraction efficiency using protein precipitation was high.The changes in neurotransmitters’levels in the brain exhibited changes during the different growth cycles.The levels of seven neurotransmitters(aspartic acid,tyrosine,isoleucine,leucine,tryptophan,valine,andγ-aminobutyric acid)were significantly different.Meanwhile,alkaloids could reduce the excitatory neurotoxicity of glutamic acid-induced SH-SY5Y cells via suppression of oxidative stress.Conclusion:Significant differences were observed in neurotransmitter profiling between 1-and 8-month-old rats,and the discrepant neurotransmitters were associated with aging.Seven indole alkaloids from Uncaria rhynchophylla,which could cross the blood-brain barrier,were screened and used to explore their protective effects against aging.Uncaria rhynchophylla alkaloids exhibited a neuroprotective effect by inhibiting oxidative stress,indicating that the alkaloid could be a potential therapeutic candidate for neurological disorders caused by glutamic acid toxicity.

Triterpenoids from Uncaria rhynchophylla and Their PTP1B Inhibitory Activity

Uncaria rhynchophylla(Gouteng)is a famous traditional Chinese medicine used for psychiatric and hypotensive purposes in China.In this study,the ethyl acetate(EtOAc)part of U.rhynchophylla was revealed with protein tyrosine phosphatase 1B(PTP1B)inhibitory activity.Subsequent investigation on the EtOAc part yielded one new triterpenoid,3β-formyloxy-6β,19α-dihydroxyurs-12-en-28-oic acid(1)and four known ones,3β,6β,19α-trihydroxyurs-12-en-28-oic acid(2),2-oxopomolic acid(3),3β,19α-dihydroxy-6-oxo-olean-12-en-28-oic acid(4)and sumaresinolic acid(5).The structure of compound 1 was determined by extensive HRESIMS,IR,1D and 2D NMR spectroscopic analyses.Two ursane-type triterpenoids(2 and 3)showed selective inhibition on PTP1B with IC50 values of 48.2 and 178.7μM.The enzyme kinetic study suggested that compounds 2 and 3 were mixtype inhibitors on PTP1B with Ki values of 15.6 and 132.5μM.This investigation manifests the antidiabetic potency of U.rhynchophylla with triterpenoids as the active constituents.

Advances in Toxicity of Ramulus et Uncus Uncariae

Ramulus et Uncus Uncariae is one of the 31 regional characteristic Chinese medicinal materials identified by Guangxi Zhuang Autonomous Region in 2021,with antihypertensive,antiarrhythmic,anti-cerebral ischemia,sedative,antithrombotic,anti-tumor and other pharmacological effects,and is neurotoxic and hepatotoxic.In this article,the chemical constituents,pharmacological effects,toxic effects,toxic manifestations in whole animals and mechanism of toxicity of Ramulus et Uncus Uncariae are reviewed.

钩藤UrTSA基因克隆及组织表达特异性分析

【目的】克隆钩藤碱的合成关键酶即色氨酸合成酶α链基因(UrTSA),并分析其组织表达特异性,为探究该基因的钩藤碱生物合成机制提供理论参考。【方法】从生物项目数据库(BioProject)筛选得到钩藤碱的生物合成相关酶基因UrTSA,以钩藤的根、叶、茎钩和蒴果的cDNA为模板,PCR克隆UrTSA基因的开放阅读框(ORF),并进行生物信息学分析,结合实时荧光定量PCR检测UrTSA基因在钩藤不同组织中的表达模式。【结果】UrTSA基因的ORF为963bp,编码320个氨基酸残基,相对分子量为33924.49Da,理论等电点(pI)为9.11,不稳定指数Ⅰ为33.50,脂溶指数为102.12,总平均亲水性指数为0.117,说明UrTSA蛋白为稳定、脂溶性好的疏水蛋白。UrTSA蛋白亚细胞定位于叶绿体,不含信号肽和跨膜区,为非分泌型蛋白;不具有潜在的糖基化位点,有30个潜在的磷酸化位点,包括16个丝氨酸(Ser)、13个苏氨酸(Thr)和1个酪氨酸(Tyr);二级结构由α-螺旋(43.44%)、无规则卷曲(31.87%)、延伸链(15.94%)和β-折叠(8.75%)组成。UrTSA蛋白与其他11个植物物种的TSA蛋白具有较高的氨基酸序列相似性(69.78%~92.77%),其中与阿拉比卡咖啡(Coffeearabica)和欧基尼奥伊德斯种咖啡(Coffeaeugenioides)TSA蛋白的亲缘关系较近。UrTSA基因在钩藤的根、叶、茎钩和蒴果中均有表达,其中在蒴果、根和叶中相对表达量均极显著高于茎钩中的相对表达量(P<0.01),分别是茎钩的2.17、1.58和1.20倍。【结论】UrTSA基因具有组织表达特异性,主要在蒴果钩藤碱合成中发挥调控作用,为后续研究钩藤碱在钩藤中不同部位的累积及其生物合成途径提供思路和线索。

Triterpenoids from the stems of Uncaria macrophylla

Nineteen triterpenoids, including eleven ursane triterpenoids and eight olenane triterpenoids, were isolated from the stems of Uncaria macrophylla Wall. by comprehensive chromatographic methods. Structure elucidation of the compounds was succeeded by extensive spectroscopic analysis. Twelve compounds were obtained from this plant for the first time, among which six compounds were obtained from the genus Uncaria for the first time.

钩藤药材的特征图谱建立、化学模式识别分析及其与不同基原、混伪品的鉴别

目的建立不同产地钩藤药材超高效液相色谱(UPLC)特征图谱,并进行化学模式识别分析,同时对钩藤不同基原样品及其混伪品进行鉴别。方法采用UPLC法建立43批不同产地钩藤药材的特征图谱,结合聚类分析及主成分分析对其进行质量分析,然后对钩藤不同基原样品及其混伪品进行鉴别。结果建立了钩藤药材UPLC特征图谱,标定了13个共有峰,并指认峰2为儿茶素、峰3为绿原酸、峰4为隐绿原酸、峰7为异绿原酸B、峰8为异去氢钩藤碱、峰9为异钩藤碱、峰10为去氢钩藤碱、峰11为异绿原酸C、峰12为钩藤碱和峰13为喜果苷。通过聚类分析可将43批钩藤药材按照产地分为5类。进一步通过主成分分析发现,江西、湖南产钩藤药材主成分综合得分较高,为0.264~2.904分。通过特征图谱可将钩藤不同基原样品及其混伪品进行有效区分。结论建立的UPLC特征图谱可用于钩藤药材的质量控制,且本研究发现江西、湖南产钩藤药材质量较优。

钩藤内生放线菌Streptomyces sp.IMW-B19化学成分研究

目的 研究钩藤内生放线菌Streptomyces sp.IMW-B19发酵产物的次生代谢产物及部分化合物的生物活性。方法 该菌株的发酵产物采用ODS、Sephadex LH-20、半制备HPLC等色谱技术进行分离纯化,并采用ESI-MS和NMR鉴定化合物的化学结构。使用人肝癌HepG2细胞评价化合物1对11β-羟类固醇脱氢酶1活性的影响。结果 共分离得到11个化合物,经多种波谱数据分析和文献对比,分别鉴定为actiphenol(1)、苯甲酸薄荷酯A(2)、cyclo(L-Pro-L-Phe)(3)、胸苷(4)、11-hydroxy-4-amorphen-15-oic acid(5)、3-吲哚甲酸甲酯(6)、苯乙酸(7)、1-(3-ethylphenyl)-ethane-1,2-diol(8)、亚油酸(9)、亚油酸甲酯(10)和2-氨基-4-甲氧基苯甲酸(11)。化合物1对11β-羟类固醇脱氢酶1具有明显的抑制作用,在20 μmol·L^(-1)时,抑制率达到86.01%。结论 从钩藤内生放线菌Streptomyces sp.IMW-B19发酵产物中共分离得到11个化合物,其中化合物4、5、8为首次从链霉菌属的放线菌中分离得到。化合物1对11β-羟类固醇脱氢酶1具有明显的抑制作用。

钩藤的药理作用及临床应用研究进展

钩藤(Uncaria rhynchophylla)是广西区域特色药材品种之一,具有息风定惊、清热平肝的功效,药用历史悠久。钩藤生物碱是钩藤的主要药效成分,对缓解药物成瘾、阿尔茨海默症、高血压等疾病具有显著功效,其方药天麻钩藤饮、复方钩藤降压片等在临床上广泛应用。随着现代医学研究技术的进步,钩藤生物碱及其方药的治病机理正在不断被发现。本文收集近十年钩藤相关研究文献,以钩藤的药效物质为基础,总结钩藤生物碱及其方药的药理研究成果,分析钩藤的临床应用情况,以期为钩藤的新药研发或新应用提供理论借鉴。

Two new ortho benzoquinones from Uncaria rhynchophylla

The present study was designed to determine the chemical constituents of the stems and hooks of Uncaria rhynchophylla. The chemical constituents were isolated and purified from CH_2Cl_2 fraction by chromatography. Their structures were elucidated by spectroscopic analyses. Their cytotoxicity was tested using MTT method. Two new ortho benzoquinones, 3-diethylamino-5-methoxy-1, 2-benzoquinone(1) and 3-ethylamino-5-methoxy-1, 2-benzoquinone(2), together with a known compound isorhynchophyllic acid(3) were isolated from U. rhynchophylla. These compounds were evaluated for their cytotoxicity against cancer cells A549, Hep G2 and A2780. Compounds 1 and 2 were new ortho benzoquinones and showed weak antiproliferative activities on A549, Hep G2 and A2780 cells. Compound 3 significantly inhibited the proliferation of A549, Hep G2 and A2780 cells with IC_(50) values being 5.8, 12.8 and 11.8 μmol·L^(–1), respectively.

钩藤UrLAMT基因及其启动子的克隆与分析

【目的】克隆钩藤(Uncaria rhynchophylla)中马钱苷酸甲基转移酶(loganic acid methyltransferase,LAMT)基因及其启动子,对UrLAMT基因的组织表达及其对生物和非生物胁迫的响应进行分析,并对UrLAMT及其启动子的生物信息学进行分析,为进一步研究UrLAMT转录调控奠定基础。【方法】基于钩藤的转录组数据设计引物,采用PCR从钩藤cDNA中克隆UrLAMT序列,并对其进行生物信息学分析;采用实时荧光定量PCR,分析UrLAMT在钩藤不同组织(根、茎、叶、花、果实、钩)中的表达,以及对外源茉莉酸甲酯(MeJA)、遮光/复光胁迫的响应;利用FPNI-PCR技术克隆UrLAMT上游启动子序列,并验证其活性,结合酵母单杂交试验,分析相应转录因子与UrLAMT启动子的调控关系。【结果】克隆得到钩藤UrLAMT序列,其长度为1137 bp,共编码378个氨基酸。UrLAMT蛋白质相对分子质量为42.64 ku,理论等电点为5.76,为亲水性蛋白,无信号肽,不含跨膜结构,定位在细胞质中;UrLAMT基因在钩藤叶中表达量最高,其次为根;UrLAMT均能响应MeJA和光;其与短小蛇根草和长春花的进化关系较近。UrLAMT启动子序列长度为1141 bp,除核心响应元件外还含有多个光响应元件,UrLAMT启动子在酵母中与光调控转录因子HY5存在相互作用。【结论】获得了UrLAMT基因及其启动子序列,其在钩藤叶中表达量最高,可能受光诱导。

Two folate-derived analogues from an aqueous decoction of Uncaria rhynchophylla

Two new folate-derived analogues,named uncarophyllofolic acids A(1)and B(2),respectively,were isolated from the Uncaria rhynchophylla hook bearing stem(Gouteng in Chinese).The distinct stereochemical structures of 1 and 2 were determined by spectroscopic data analysis in combination with acidic hydrolysis and Marfey’s derivatization,along with comparison of their specific rotation and Cotton effect(CE)data with those of the biogenetically related known derivatives as well as theoretical calculations of electronic circular dichroism(ECD)spectra.A plausible biosynthetic pathway of 1 and 2,associating to folate metabolism and the previously reported orychophragines A-C from Orychophragmus violaceus,is discussed.