Silica gel column chromatography(CC),Sephadex LH-20 CC and high performance liquid chromatography(HPLC)were used to study the chemical constituents of the fruits of the medicine-food plant Rubus idaeus Linnaeus.A new ...Silica gel column chromatography(CC),Sephadex LH-20 CC and high performance liquid chromatography(HPLC)were used to study the chemical constituents of the fruits of the medicine-food plant Rubus idaeus Linnaeus.A new tetrahydrogenated naphthol syringic acid ester,named rubusnolicester(1),two new phenolic glycoside derivatives,4-chloro-2,6-dimethoxylphenol-1-O-β-D-glucopyranoside(2)and salicylic acid-2-O-(6'-O-acetyl)-β-D-glucopyranoside(3),together with one known salicylic acid glycoside derivative(4)and three known flavonoids derivatives(5~7),were isolated.Their structures were elucidated by HRESI-MS,NMR spectroscopy,and a comparison of optical rotation(OR).Compounds 1~7 were evaluated the inhibitory activities against the nitric oxide(NO)production induced by lipopolysaccharide(LPS)in mouse macrophage RAW264.7 cells in vitro.Compound 1 exhibited inhibitory effect with the IC50 value of(12.28±1.25)μmol/L.展开更多
Background: Medical plants are a diverse group of commercially important plants thatprovide raw materials for pharmaceuticals, perfumes, flavors, and cosmetics. They includenumerous secondary metabolites and may conta...Background: Medical plants are a diverse group of commercially important plants thatprovide raw materials for pharmaceuticals, perfumes, flavors, and cosmetics. They includenumerous secondary metabolites and may contain medications. Mahareeb is a Poaceaemedicinal plant containing compounds that prevent infections and boost herbal treatmentsfor pathogen-related diseases. Methods: In this study, the traditional herb Lemongrass(Mahareeb), used as phytomedicines in Gezira State, was examined for phytochemical,GC-MS analysis, antibacterial, antioxidant, and synergistic effects with antibiotics. Bacteriaresistant to medicines and other therapies, which included: Staphylococcus aureus (S. aureus),Salmonella typhi (Sal. typhi), Pseudomonas aeruginosa (P. aeruginosa), Escherichia coli (E. coli),and Klebsiella pneumoniae (K. pneumoniae) were examined. The antioxidant activity of theplant was compared to reference molecules using phenols, tannins, flavonoids, DPPH,reducing power, β-carotene, and ABTS IC50 (mg/mL) scavenging. The synergy ofplant-antibiotics was evaluated using disk diffusion, while GC-MS was utilized to determinebioactive components. Results: The results showed that Mahareeb extract inhibited alltested bacteria, and its inhibitory effect increased with the extract concentration. Thephytochemical screening revealed the presence of flavonoids, steroids, and Terpenoids, butno tannins or saponins were detected. The results demonstrate potential antioxidant efficacyat low concentrations compared to ascorbic acid (A.A.), butylate hydroxytoluene (BHT), andβ-carotene. Antibiotics and plant extracts inhibited testing bacteria to varied degrees. TheGC-MS analysis of Mahareeb revealed the presence of 23 bioactive compounds withretention durations of 5.348-14.123 minutes. The study proposes isolating activecomponents and developing medicines Conclusions:. Mahareeb leaf extract has potential asa supplement to antibiotics, but its efficacy is unclear due to lack of explanation forlimonene and citral suppression and lack of testing under different conditions.展开更多
Plant pathogens secrete various cell wall-degrading enzymes that compromise host cell wall integrity and facilitate pathogen invasion.This study identified VdGH7a,a glycoside hydrolase family 7(GH7)cellobiohydrolase f...Plant pathogens secrete various cell wall-degrading enzymes that compromise host cell wall integrity and facilitate pathogen invasion.This study identified VdGH7a,a glycoside hydrolase family 7(GH7)cellobiohydrolase from Verticillium dahliae,which demonstrated hydrolytic activity against 1,4-β-glucan.Notably,VdGH7a induced cell death in Nicotiana benthamiana when signal peptides were present,though this effect was inhibited by the carbohydrate-binding type-1(CBM1)protein domain.The deletion of VdGH7a substantially reduced V.dahliae pathogenicity in cotton plants,as demonstrated by the mutants’inability to penetrate cellophane membrane.These knockout mutants also exhibited reduced carbon source utilization capacity and increased sensitivity to osmotic and cell wall stresses.Through yeast two-hybrid screening,bi-molecular fluorescence complementation(BiFC),and luciferase complementation imaging(LCI),we identified that VdGH7a interacts with an osmotin-like protein(GhOLP1)in cotton.Virus-induced gene silencing of GhOLP1 resulted in decreased salicylic acid(SA)content and reduced resistance to V.dahliae in cotton,while heterologous overexpression of GhOLP1 in Arabidopsis enhanced both resistance and SA signaling pathway gene expression.These results reveal a virulence mechanism wherein the secreted protein VdGH7a from V.dahliae interacts with GhOLP1 to activate host immunity and contribute significantly to plant resistance against V.dahliae.展开更多
Camptothecin,a plant-derived pentacyclic pyrroloquinoline alkaloid,and its derivatives like topotecan and irinotecan have been used as clinical anticancer agents for decades.However,the complete biosynthetic pathway o...Camptothecin,a plant-derived pentacyclic pyrroloquinoline alkaloid,and its derivatives like topotecan and irinotecan have been used as clinical anticancer agents for decades.However,the complete biosynthetic pathway of camptothecin still remains unelucidated due to the unknown complex formation processes and corresponding enzymes for the downstream biosynthetic pathway including the committed hydrolysis of glycosides.Herein,a novel glycoside hydrolase(CaGH1)responsible for the deglycosylation of biosynthetic glycoside intermediates including both quinoline-type alkaloids pumiloside(1),(3S)-deoxypumiloside(2)and indole-type alkaloid strictosamide(3)has been functionally identified.Moreover,CaGH1 exhibits the highly strict stereoselectivity towards the substrates with 3S configuration.Furthermore,a combined strategy for the discovery of the unknown biosynthetic enzyme by employing activity-guided enzyme verification,transcriptome-based gene mining,biochemical assay in vitro,and structurally characterizing the unstable enzymatic products by derivatization,is reported.These findings not only provide a better understanding of the deglycosylation in camptothecin biosynthesis,also lay the foundation for the complete elucidation of camptothecin biosynthetic pathway and biological production of camptothecin.展开更多
3-Deoxy-D-manno–oct-2-ulosonic acid(Kdo)is widely distributed in bacteria,and the synthesis of Kdocontaining oligosaccharides is important for the development of novel antibiotics and immunological agents.We have rec...3-Deoxy-D-manno–oct-2-ulosonic acid(Kdo)is widely distributed in bacteria,and the synthesis of Kdocontaining oligosaccharides is important for the development of novel antibiotics and immunological agents.We have recently developed a strategy to achieveα-stereocontrolled glycosylation using a C3-p-tolylthio-substituted Kdo phosphite donor.The wide substrate scope and high reactivity of the donors enabled the efficient synthesis of a series of Kdo-containing glycosides with completeα-stereoselectivity and without the formation of 2,3-ene byproducts.In this study,we improved the method by replacing the leaving group diethyl phosphite with fluoride,which enhanced the stability of the donor and led to cleaner reaction.Furthermore,the substrate range was expanded by synthesizing a series of Kdo O/C/S/Nglycosides,which also opened up a new avenue for the synthesis of CMP-Kdo synthase inhibitors.展开更多
Laminarin oligosaccharides(LOSs)with a specific degree of polymerization prepared through the laminarin degradation via laminarinase present more significant nutritional functions and application values.Human intestin...Laminarin oligosaccharides(LOSs)with a specific degree of polymerization prepared through the laminarin degradation via laminarinase present more significant nutritional functions and application values.Human intestinal bacteria are promising potential producers of novel carbohydrate-active enzymes with unique properties.Here,a novel glycoside hydrolase family 128(GH128)laminarinase OUC-BsLam26 from the intestinal bacterium Bacteroides sp.CBA7301 was heterologously expressed and characterized.The recombinant OUC-BsLam26 with a molecular mass of 49.86 kDa exhibits highest activity(6.60 U/mg)at 45℃ and pH 6.0,which shows noticeable temperature and pH stability.The purified OUC-BsLam26 could degrade laminarin via an endo-type mode with the generation of laminaripentaose,laminaritetraose,laminaritriose,and laminaribiose,among them,laminaritetraose is the principal product,which accounts for 45.25% of the total products,which is significantly different from the reported GH128 laminarinases.The minimum recognition substrate of OUC-BsLam26 is laminarihexaose.Furthermore,OUC-BsLam26 also could catalyze the transglycosylation process with the production of some novel glycosides.Altogether,the intestinal bacterium Bacteroides sp.CBA7301 contains laminarinase with unique product composition and OUC-BsLam26 is a hopeful bio-catalyst with the potential to produce laminaritetraose and some novel glycosides.展开更多
Background:Qingyangshen(Cynanchum otophyllum C.K.Schneid)is a folk drug for treating depression and other mental disorders induced by social defeat stress.Neuroplasticity in the hippocampus is essential for the modula...Background:Qingyangshen(Cynanchum otophyllum C.K.Schneid)is a folk drug for treating depression and other mental disorders induced by social defeat stress.Neuroplasticity in the hippocampus is essential for the modulation of cognition and emotion,and its impairment may contribute to the development and progression of depression.Our previous studies have found that Qingyangshen glycosides(QYS)can improve depression-like behavior in social failure mouse models,mainly through PGC-1α/FNDC5/BDNF signaling pathways activation,but its effects and mechanisms on hippocampal neuroplasticity remain unknown.Methods:Chronic social defeat stress(CSDS)was used to induce social defeat in mice.Morphological changes in the hippocampus were observed by H&E staining and Golgi staining.Immunofluorescence double staining was used to detect the expression of synaptophysin(SYN)and postsynaptic density protein-95(PSD-95),while western blot was employed to evaluate PSD-95,SYN,and doublecortin(DCX)proteins.The pathological processing of social defeat and the therapeutic effects of QYS on it was confirmed through behavioral assessment associated with morpho-logic observation.Results:During the whole study,the sucrose preference indices and OFT activity time of CSDS mice were significantly decreased(p≤0.05),and the tail suspension immobil-ity time was significantly increased(p≤0.05),suggesting that the mice had significant depressive symptoms.Treatment with QYS(25,50,and 100 mg/kg)significantly al-leviated depressive symptoms in CSDS mice,which was demonstrated by significantly(p≤0.05 or p≤0.01)reducing the duration of tail-hanging immobility and increasing the tendency of sucrose preference indices and OFT activity time.QYS treatment also significantly increased the expression of DCX,PSD-95,and SYN proteins,which play a crucial role in depression.Conclusions:QYS alleviated these symptoms by enhancing hippocampal neuroplasti-city through upregulating the expression of synapse-associated proteins(SAPs).The therapeutic mechanism of QYS may involve modulating the neuroplasticity of hip-pocampus neurons by altering the expression of SAPs.展开更多
Phytochemical study of the n-BuOH extract of Ilex asprella resulted in the discovery of ten new pentacyclic triterpenoid glycosides,comprising nine ursane-type glycosides(1-9)and one oleanane-type glycoside(10),along ...Phytochemical study of the n-BuOH extract of Ilex asprella resulted in the discovery of ten new pentacyclic triterpenoid glycosides,comprising nine ursane-type glycosides(1-9)and one oleanane-type glycoside(10),along with seven known compounds(11-17).Compound 1 is the first reported 19,22-epoxy ursane triterpenoid glycoside,whereas 4 and 5 are rare examples of ursane triterpenoid glycosides containing a 28,19-lactone group.The structural characterization of these compounds was achieved using spectroscopic and chemical techniques,as well as single-crystal X-ray analysis.Compounds 7,12,15,and 17 exhibited moderate cytotoxic activities against H1975 and HCC827 cancer cells.展开更多
This study investigates the pharmacokinetics and metabolic characteristics of three marinederived piericidins as potential drug leads for kidney disease:piericidin A(PA)and its two glycosides(GPAs),glucopiericidin A(G...This study investigates the pharmacokinetics and metabolic characteristics of three marinederived piericidins as potential drug leads for kidney disease:piericidin A(PA)and its two glycosides(GPAs),glucopiericidin A(GPA)and 13-hydroxyglucopiericidin A(13-OH-GPA).The research aims to facilitate lead selection and optimization for developing a viable preclinical candidate.Rapid absorption of PA and GPAs in mice was observed,characterized by short half-lives and low bioavailability.Glycosides and hydroxyl groups significantly enhanced the absorption rate(13-OH-GPA>GPA>PA).PA and GPAs exhibited metabolic instability in liver microsomes due to Cytochrome P450 enzymes(CYPs)and uridine diphosphoglucuronosyl transferases(UGTs).Glucuronidation emerged as the primary metabolic pathway,with UGT1A7,UGT1A8,UGT1A9,and UGT1A10 demonstrating high elimination rates(30%-70%)for PA and GPAs.This rapid glucuronidation may contribute to the low bioavailability of GPAs.Despite its low bioavailability(2.69%),13-OH-GPA showed higher kidney distribution(19.8%)compared to PA(10.0%)and GPA(7.3%),suggesting enhanced biological efficacy in kidney diseases.Modifying the C-13 hydroxyl group appears to be a promising approach to improve bioavailability.In conclusion,this study provides valuable metabolic insights for the development and optimization of marine-derived piericidins as potential drug leads for kidney disease.展开更多
Anoectochilus roxburghii from different planting sources was used as the research object,and the biological activity of its extracts was compared.The results showed that the whole plant extracts of A.roxburghii plante...Anoectochilus roxburghii from different planting sources was used as the research object,and the biological activity of its extracts was compared.The results showed that the whole plant extracts of A.roxburghii planted in bag culture (BAG),greenhouse cultivation (GRE) and tissue culture seedlings (TIS) were rich in active ingredients such as A.roxburghii polysaccharides and A.roxburghii glycosides.In vitro experiments showed that Anoectochilus roxburghii extracts from different planting sources had good antioxidant capacity,tyrosinase inhibition ability and hyaluronidase inhibition ability.Among them,the GRE Anoectochilus roxburghii whole plant extract had the strongest scavenging ability on DPPH free radical,ABTS free radical and hydroxyl free radical,and the inhibitory effect on tyrosinase activity and hyaluronidase activity was significantly higher than that of BAG and TIS.At the same time,it also verified that the extract of Anoectochilus roxburghii has antioxidant,whitening,anti-inflammatory and other skin care effects,which provides a theoretical basis for the development and application of Anoectochilus roxburghii extract in the field of cosmetics.展开更多
Five new flavan-4-ol glycosides jixueqiosides A-E(1-5)and two new flavan glycosides jixueqiosides F and G(6 and 7),along with twelve known flavan-4-ol glycosides(8-19),were isolated from the roots of Pronephrium penan...Five new flavan-4-ol glycosides jixueqiosides A-E(1-5)and two new flavan glycosides jixueqiosides F and G(6 and 7),along with twelve known flavan-4-ol glycosides(8-19),were isolated from the roots of Pronephrium penangianum.Comprehensive spectral analyses,X-ray single-crystal diffraction,and theoretical electronic circular dichroism(ECD)calculations established structures and absolute configurations.A single crystal structure of flavan-4-ol glycoside(14)was reported for the first time,while the characteristic ECD and NMR data for all isolated flavan-4-ol glycosides(1-5,8-19)were analyzed,establishing a set of empirical rules.Activity screening of these isolates showed that 8 and 9 could inhibit the proliferation of MDA-MB-231 and MCF-7 cells with IC50 values of 7.93±2.85μmol·L^(-1)and 5.87±1.58μmol·L^(-1)(MDA-MB-231),and 2.21±1.38μmol·L^(-1)and 3.52±1.55μmol·L^(-1)(MCF-7),respectively.Western blotting and flow cytometry analyses demonstrated that 8 and 9 dose-dependently induced apoptosis in MDA-MB-231 cells by up-regulating BAX,activating caspase-3 and down-regulating BCL-2.Additionally,compound 8 affected autophagy-related proteins,increasing the ratio of LC3-II/LC3-I and Beclin-1 levels to inhibit MDA-MB-231 cell proliferation.Moreover,anti-inflammatory studies indicated that 2,3,7,13,14,and 18 moderately inhibited tumor necrosis factor-α(TNF-α),interleukin-6(IL-6),and nitric oxide(NO)release.展开更多
Food-derived polysaccharides are gaining popularity across diverse food applications due to their wideranging bioactivities and distinctive properties.The specific targeting of glycoside hydrolases towards glycosidic ...Food-derived polysaccharides are gaining popularity across diverse food applications due to their wideranging bioactivities and distinctive properties.The specific targeting of glycoside hydrolases towards glycosidic bonds lays the groundwork for synthesizing and exploring specific structural segments of polysaccharides,offering crucial implications in the food industry.However,macromolecular polysaccharides demonstrate limited biological activities as their active centers are tightly enveloped,posing challenges for traversing cell membrane barriers.By selectively cleaving partial glycosidic linkages in polysaccharides,glycoside hydrolases decrease the polymerization of polysaccharide molecules and effectively change the structural characteristics,where a series of smaller polysaccharide fragments can be generated for improving the bioactivities and properties in some respects.This review examines the role of glycoside hydrolases in degrading food-derived polysaccharides,the structure-function relationships,reaction conditions,and the current application status of degraded polysaccharides is discussed in particular.In addition,we also highlight challenges and future directions worth attention in the application of enzymes and polysaccharides.Overall,the present review will provide an efficient method for producing bioactivity-enhanced polysaccharides,which can improve the effectiveness and safety of functional foods to safeguard human wellness.展开更多
The high content of cyanogenic glycosides(CG)in cassava tubers affects food safety.CG are involved in the plant growth and development and protect cassava leaves from herbivorous predators.However,the regulatory mecha...The high content of cyanogenic glycosides(CG)in cassava tubers affects food safety.CG are involved in the plant growth and development and protect cassava leaves from herbivorous predators.However,the regulatory mechanism of CG biosynthesis remains poorly understood.Here,yeast one-hybrid assays were performed using a mixed cDNA library of cassava tubers and leaves as prey and the promoter of MeCYP79D2 as bait.MeCYP79D2,a cytochrome P450 protein,is the rate-limiting enzyme for CG synthesis in cassava.From this information,a candidate regulator of MeCYP79D2 was selected and identified as transcription factor MePHD1.2.MePHD1.2,located in the nucleus and exhibiting an inhibitory transcription activity directly bound to an AT-rich motif in the promoter of MeCYP79D2.In cassava,the transcriptional activity of MeCYP79D2 was considerably enhanced in mephd1.2 mutant lines leading to increased linamarin and lotaustralin contents.Deletion of MePHD1.2 promoted the production of CGs in cassava and decreased transcription inhibition on MeCYP79D2,exposing a novel regulatory module governing biosynthesis of CGs.展开更多
Abstract： In the present study, we established an ultra performance liquid chromatography coupled with time-of-flight mass spectrometry （UPLC-QTOF-MSE） method to simultaneously quantify 33 components in Ginkgo bilo...Abstract： In the present study, we established an ultra performance liquid chromatography coupled with time-of-flight mass spectrometry （UPLC-QTOF-MSE） method to simultaneously quantify 33 components in Ginkgo biloba leaf extracts （GBEs）, including 17 flavonol glycosides, five terpene trilactones （TTLs）, four polyphenols and seven carboxylic acids. This optimized method was successfully applied to analyze the explicit compositions of GBE samples collected from different places. Furthermore, the data were processed through unsupervised principal component analysis （PCA） and supervised orthogonal partial least squared discrimination analysis （OPLS-DA） to evaluate the quality and compare the differences between the samples according to the contents of the 33 chemical constituents. Bilobalide, protocatechuic acid, shikimic acid, quinic acid, ginkgolide B, ginkgolide J, kaempferol-3-O-rutinoside, isorhamnetin-3-O-rutinoside, quercetin-3-O-ct-L-rhamnopyranocyl-2＂-（6＇＂-p-coumaroyl）-β-D-glucoside and rutin were recognized as characteristic chemical markers that contributed most to control the quality of GBEs. Based on the fact that GBEs should be standardized with the characteristic components as quality control chemical markers, it is most important to maintain the quality of GBEs stable and reliable, and this method also provided a good strategy to further rectify and standardize the GBEs market.展开更多
Aim To investigate the chemical composition of Ranunculus sieboldii Miq..Methods Repeated column chromatography over silica gel, polyamide and RP-18 followed by gelfiltration on sephadex LH-20 were used to isolate che...Aim To investigate the chemical composition of Ranunculus sieboldii Miq..Methods Repeated column chromatography over silica gel, polyamide and RP-18 followed by gelfiltration on sephadex LH-20 were used to isolate chemical constituents, and their structures wereelucidated by extensive spectroscopic methods (UV, IR, MS, ~1H NMR, ^(13)C NMR) including 2D NMR(COSY, HMQC, HMBC, NOESY) techniques and by direct comparing spectral data with those reported inliterature. Results Five flavonoid glycosides named apigenin-4'-O-α-L-rhamnopyranoside (1),apigenin-7-O-β-D-glucopyranosyl-4'-O-α-L-rhamnopyranoside (2), apigenin-8-C-α-L-arabinopyranoside(3), apigenin-8-C-β-D-ga-lactopyranoside (4) , tricin-7-O-β-D-glucopyranoside (5), together withtricin (6), luteolin (7), scopoletin (8), esculetin (9), scoparone (10), ferulic acid (11),protocatechuic acid (12) , and tematolide (13) were isolated from the 95% etha-nolic extract of itswhole plant, and their cytotoxic activities were preliminarily tested. Conclusion Compounds 1-12were obtained from this genus and compound 13 from this species for the first time. Furthermore,compound 1 was for the first time isolated from nature while the ^(13)C NMR data of compounds 2 and3 are reported for the first time. The bioassay revealed that compound 1 was active against BEL-7407and A549 cell lines (IC_(45) 43, 77 μg·mL^(-1)), 8 and 10 showed inhibitory activities on KB celllines (IC_(50) 78, 44 μg·mL^(-1)) and HL-60 cell lines (Ic_(50) 85, 85 μg·mL^(-1)), while 7exerted moderate cytotoxic activities on KB, BFL-7407, A549 and HL-60 cell lines with their IC_(50)being 51, 55, 44 and 10 μg·mL^(-1) , respectively.展开更多
Parvifloside (1), a new furostanol pentaglycoside, was isolated from the fresh rhizomes of Dioscorea parviflora C. T. Ting. On the basis of spectroscopic and chemical methods, its structure was elucidated as (25R)-26...Parvifloside (1), a new furostanol pentaglycoside, was isolated from the fresh rhizomes of Dioscorea parviflora C. T. Ting. On the basis of spectroscopic and chemical methods, its structure was elucidated as (25R)-26-O-β-glucopyranosyl-furost-5-en-3β,22ξ,26-triol 3-O-β-D-glucopyranosyl (1→3)-β-D-glucopyranosyl (1→4)-[α-L-rhamnopyranosyl (1→2)]-β-D-glucopyranoside. Six prosapogenins (2-7)were obtained from the enzymatic degradation of 1by cellulase, but only 3 and 4 were obtained by β-glucosidase. The structures of all compounds were determined by spectroscopic data. The activity of the isolated compounds on deformation of mycelia germinated from Pyricularia oaryzae P-2b conidia was evaluated.展开更多
Two new phenylpropanetriol glycosides, named as meliadanoside A (3 - methoxy- 5 - hydroxy-9- (1' - O-β-D-glucopyranosyl) - threo - phenylpropanetriol ) and meliadanoside B (4- hydroxy-7, 8- (2', 1' - O- ...Two new phenylpropanetriol glycosides, named as meliadanoside A (3 - methoxy- 5 - hydroxy-9- (1' - O-β-D-glucopyranosyl) - threo - phenylpropanetriol ) and meliadanoside B (4- hydroxy-7, 8- (2', 1' - O- β- D -glucopyranosyl) - phenylpropanetriol), were isolated from the water-soluble extract of the fruits of Meliatoosendan Sieb. et Zucc., along with threo-guaiacylglycerol. Their structures were elucidated by spectroscopic and chendcal analysis.展开更多
Introduction The plants of genus Cistanche G. Beck, which belong to Orobanchaceae family, include about twenty species, and there are four species and one variety are distributed in the northwest part of China. The d...Introduction The plants of genus Cistanche G. Beck, which belong to Orobanchaceae family, include about twenty species, and there are four species and one variety are distributed in the northwest part of China. The dried fleshy stem of Cistanche genus plant known as ＇Roucongrong＇ in Chinese traditional medicine, has long been used for kidney deficiency, female infertility, morbid leucorrhea, and neurasthenia. Studies on active components and pharmacological activities show that it possesses significant activities in enhancing potency, anti-fatigue, immuno-modulability, etc, and phenylethanoid glycosides are the major active components. Due to excessive exploitation, its natural resources are facing with exhaustion. In order to improve this situation, the plant has been cultivated on a large scale in the northwest part of China. Up to now, the chemical investigations of the cultivated Cistartcbe salsa have not been undertaken. In this paper we report seven phenylethanoid glycosides from the cultivated Cistanche salsa： echinacoside （1）, cistanoside A （2）, acteoside （3）, isoacteoside （4）, 2＇-acetylacteoside （5）, tubuloside B （6）, and eutigoside A （7）. Among them, compound 7 isolated fronl family Orobanchaceae was reported previously, and compounds 1, 2, 3, 4, 5 and 6 from the cultivated Cistanche salsa are reported for the first time.展开更多
[Objective] The paper was to study the effect of potato extract on its phenolic metabolism,SAGs accumulation and allelopathic autotoxicity.[Method] With water treatment as control,the effects of aqueous extracts of po...[Objective] The paper was to study the effect of potato extract on its phenolic metabolism,SAGs accumulation and allelopathic autotoxicity.[Method] With water treatment as control,the effects of aqueous extracts of potato bud,leaf-stem and tuber on its morphological characteristics,phenolic metabolism,glycoside alkaloids accumulation and allelopathic autotoxicity were studied.[Result] After the treatment of aqueous extract,the germination rate of potato reduced,germination was delayed,the plants became smaller,and the growth of root slowed down;the content of phenolic substances in roots,stems and leaves of potato increased,glycoside alkaloids accumulated,the activity of PPO and PAL increased.The effects of aqueous extract treatment on germination,growth,phenolic metabolism,glycoside alkaloid content and allelopathic autotoxicity successively were bud extractleaf-stem extracttuber extractcontrol.Treatment of aqueous extract did not affect the distribution of phenolic substances and glycosidic alkaloid in potato.[Conclusion] Phenolic substances and glycosidic alkaloid involved in the allelopathic autotoxicity of aqueous extract of potato,which had inhibition effect on germination and growth of potato.展开更多
文摘Silica gel column chromatography(CC),Sephadex LH-20 CC and high performance liquid chromatography(HPLC)were used to study the chemical constituents of the fruits of the medicine-food plant Rubus idaeus Linnaeus.A new tetrahydrogenated naphthol syringic acid ester,named rubusnolicester(1),two new phenolic glycoside derivatives,4-chloro-2,6-dimethoxylphenol-1-O-β-D-glucopyranoside(2)and salicylic acid-2-O-(6'-O-acetyl)-β-D-glucopyranoside(3),together with one known salicylic acid glycoside derivative(4)and three known flavonoids derivatives(5~7),were isolated.Their structures were elucidated by HRESI-MS,NMR spectroscopy,and a comparison of optical rotation(OR).Compounds 1~7 were evaluated the inhibitory activities against the nitric oxide(NO)production induced by lipopolysaccharide(LPS)in mouse macrophage RAW264.7 cells in vitro.Compound 1 exhibited inhibitory effect with the IC50 value of(12.28±1.25)μmol/L.
文摘Background: Medical plants are a diverse group of commercially important plants thatprovide raw materials for pharmaceuticals, perfumes, flavors, and cosmetics. They includenumerous secondary metabolites and may contain medications. Mahareeb is a Poaceaemedicinal plant containing compounds that prevent infections and boost herbal treatmentsfor pathogen-related diseases. Methods: In this study, the traditional herb Lemongrass(Mahareeb), used as phytomedicines in Gezira State, was examined for phytochemical,GC-MS analysis, antibacterial, antioxidant, and synergistic effects with antibiotics. Bacteriaresistant to medicines and other therapies, which included: Staphylococcus aureus (S. aureus),Salmonella typhi (Sal. typhi), Pseudomonas aeruginosa (P. aeruginosa), Escherichia coli (E. coli),and Klebsiella pneumoniae (K. pneumoniae) were examined. The antioxidant activity of theplant was compared to reference molecules using phenols, tannins, flavonoids, DPPH,reducing power, β-carotene, and ABTS IC50 (mg/mL) scavenging. The synergy ofplant-antibiotics was evaluated using disk diffusion, while GC-MS was utilized to determinebioactive components. Results: The results showed that Mahareeb extract inhibited alltested bacteria, and its inhibitory effect increased with the extract concentration. Thephytochemical screening revealed the presence of flavonoids, steroids, and Terpenoids, butno tannins or saponins were detected. The results demonstrate potential antioxidant efficacyat low concentrations compared to ascorbic acid (A.A.), butylate hydroxytoluene (BHT), andβ-carotene. Antibiotics and plant extracts inhibited testing bacteria to varied degrees. TheGC-MS analysis of Mahareeb revealed the presence of 23 bioactive compounds withretention durations of 5.348-14.123 minutes. The study proposes isolating activecomponents and developing medicines Conclusions:. Mahareeb leaf extract has potential asa supplement to antibiotics, but its efficacy is unclear due to lack of explanation forlimonene and citral suppression and lack of testing under different conditions.
基金supported by the Project of Sanya Yazhou Bay Science and Technology City,China(SCKJ-JYRC-2022-75)the Natural Science Foundation of Hainan Province,China(322QN398).
文摘Plant pathogens secrete various cell wall-degrading enzymes that compromise host cell wall integrity and facilitate pathogen invasion.This study identified VdGH7a,a glycoside hydrolase family 7(GH7)cellobiohydrolase from Verticillium dahliae,which demonstrated hydrolytic activity against 1,4-β-glucan.Notably,VdGH7a induced cell death in Nicotiana benthamiana when signal peptides were present,though this effect was inhibited by the carbohydrate-binding type-1(CBM1)protein domain.The deletion of VdGH7a substantially reduced V.dahliae pathogenicity in cotton plants,as demonstrated by the mutants’inability to penetrate cellophane membrane.These knockout mutants also exhibited reduced carbon source utilization capacity and increased sensitivity to osmotic and cell wall stresses.Through yeast two-hybrid screening,bi-molecular fluorescence complementation(BiFC),and luciferase complementation imaging(LCI),we identified that VdGH7a interacts with an osmotin-like protein(GhOLP1)in cotton.Virus-induced gene silencing of GhOLP1 resulted in decreased salicylic acid(SA)content and reduced resistance to V.dahliae in cotton,while heterologous overexpression of GhOLP1 in Arabidopsis enhanced both resistance and SA signaling pathway gene expression.These results reveal a virulence mechanism wherein the secreted protein VdGH7a from V.dahliae interacts with GhOLP1 to activate host immunity and contribute significantly to plant resistance against V.dahliae.
基金financially supported by the National Key Research and Development Program of China(No.2020YFA0908000)CAMS Innovation Fund for Medical Sciences(No.CIFMS-2023I2M-2–006)。
文摘Camptothecin,a plant-derived pentacyclic pyrroloquinoline alkaloid,and its derivatives like topotecan and irinotecan have been used as clinical anticancer agents for decades.However,the complete biosynthetic pathway of camptothecin still remains unelucidated due to the unknown complex formation processes and corresponding enzymes for the downstream biosynthetic pathway including the committed hydrolysis of glycosides.Herein,a novel glycoside hydrolase(CaGH1)responsible for the deglycosylation of biosynthetic glycoside intermediates including both quinoline-type alkaloids pumiloside(1),(3S)-deoxypumiloside(2)and indole-type alkaloid strictosamide(3)has been functionally identified.Moreover,CaGH1 exhibits the highly strict stereoselectivity towards the substrates with 3S configuration.Furthermore,a combined strategy for the discovery of the unknown biosynthetic enzyme by employing activity-guided enzyme verification,transcriptome-based gene mining,biochemical assay in vitro,and structurally characterizing the unstable enzymatic products by derivatization,is reported.These findings not only provide a better understanding of the deglycosylation in camptothecin biosynthesis,also lay the foundation for the complete elucidation of camptothecin biosynthetic pathway and biological production of camptothecin.
基金supported by the National Key R&D Program of China(Nos.2022YFF1203005,2022YFC2303700)supported by the National Natural Science Foundation of China(Nos.81930097,82151223).
文摘3-Deoxy-D-manno–oct-2-ulosonic acid(Kdo)is widely distributed in bacteria,and the synthesis of Kdocontaining oligosaccharides is important for the development of novel antibiotics and immunological agents.We have recently developed a strategy to achieveα-stereocontrolled glycosylation using a C3-p-tolylthio-substituted Kdo phosphite donor.The wide substrate scope and high reactivity of the donors enabled the efficient synthesis of a series of Kdo-containing glycosides with completeα-stereoselectivity and without the formation of 2,3-ene byproducts.In this study,we improved the method by replacing the leaving group diethyl phosphite with fluoride,which enhanced the stability of the donor and led to cleaner reaction.Furthermore,the substrate range was expanded by synthesizing a series of Kdo O/C/S/Nglycosides,which also opened up a new avenue for the synthesis of CMP-Kdo synthase inhibitors.
基金supported by the National Natural Science Foundation of China(32072159)Natural Science Foundation of Hainan Province(322QN338)+4 种基金Young Talent of Lifting Engineering for Science and Technology in Shandong,China(SDAST2021qt18)Qingdao Science and Technology Plan Key Research and Development Project(22-3-3-hygg-28-hy)Fundamental Research Funds for the Central Universities(202262003)Taishan Scholar Project of Shandong Province(tsqn202312099)Support Program for Youth Innovation Technology in Colleges and Universities of Shandong Province(2023KJ041)。
文摘Laminarin oligosaccharides(LOSs)with a specific degree of polymerization prepared through the laminarin degradation via laminarinase present more significant nutritional functions and application values.Human intestinal bacteria are promising potential producers of novel carbohydrate-active enzymes with unique properties.Here,a novel glycoside hydrolase family 128(GH128)laminarinase OUC-BsLam26 from the intestinal bacterium Bacteroides sp.CBA7301 was heterologously expressed and characterized.The recombinant OUC-BsLam26 with a molecular mass of 49.86 kDa exhibits highest activity(6.60 U/mg)at 45℃ and pH 6.0,which shows noticeable temperature and pH stability.The purified OUC-BsLam26 could degrade laminarin via an endo-type mode with the generation of laminaripentaose,laminaritetraose,laminaritriose,and laminaribiose,among them,laminaritetraose is the principal product,which accounts for 45.25% of the total products,which is significantly different from the reported GH128 laminarinases.The minimum recognition substrate of OUC-BsLam26 is laminarihexaose.Furthermore,OUC-BsLam26 also could catalyze the transglycosylation process with the production of some novel glycosides.Altogether,the intestinal bacterium Bacteroides sp.CBA7301 contains laminarinase with unique product composition and OUC-BsLam26 is a hopeful bio-catalyst with the potential to produce laminaritetraose and some novel glycosides.
基金Guizhou Administration of TCM,Traditional Chinese medicine,Ethnic Medicine Science and Technology Research Special Project,Grant/Award Number:QZYY-2022-008Subsidy Fund for Scientific Research and Innovation Exploration Project,National Natural Science Foundation of China of Guizhou University of Traditional Chinese Medicine,Grant/Award Number:2018YFC170810502+1 种基金Science and Technology Fund Project of Guizhou Provincial Health Commission,Grant/Award Number:gzwkj2023-147Development of animal models for drug discovery-brain diseases.National Research and Development Project of China,MOST,Grant/Award Number:2023YFF0724802.
文摘Background:Qingyangshen(Cynanchum otophyllum C.K.Schneid)is a folk drug for treating depression and other mental disorders induced by social defeat stress.Neuroplasticity in the hippocampus is essential for the modulation of cognition and emotion,and its impairment may contribute to the development and progression of depression.Our previous studies have found that Qingyangshen glycosides(QYS)can improve depression-like behavior in social failure mouse models,mainly through PGC-1α/FNDC5/BDNF signaling pathways activation,but its effects and mechanisms on hippocampal neuroplasticity remain unknown.Methods:Chronic social defeat stress(CSDS)was used to induce social defeat in mice.Morphological changes in the hippocampus were observed by H&E staining and Golgi staining.Immunofluorescence double staining was used to detect the expression of synaptophysin(SYN)and postsynaptic density protein-95(PSD-95),while western blot was employed to evaluate PSD-95,SYN,and doublecortin(DCX)proteins.The pathological processing of social defeat and the therapeutic effects of QYS on it was confirmed through behavioral assessment associated with morpho-logic observation.Results:During the whole study,the sucrose preference indices and OFT activity time of CSDS mice were significantly decreased(p≤0.05),and the tail suspension immobil-ity time was significantly increased(p≤0.05),suggesting that the mice had significant depressive symptoms.Treatment with QYS(25,50,and 100 mg/kg)significantly al-leviated depressive symptoms in CSDS mice,which was demonstrated by significantly(p≤0.05 or p≤0.01)reducing the duration of tail-hanging immobility and increasing the tendency of sucrose preference indices and OFT activity time.QYS treatment also significantly increased the expression of DCX,PSD-95,and SYN proteins,which play a crucial role in depression.Conclusions:QYS alleviated these symptoms by enhancing hippocampal neuroplasti-city through upregulating the expression of synapse-associated proteins(SAPs).The therapeutic mechanism of QYS may involve modulating the neuroplasticity of hip-pocampus neurons by altering the expression of SAPs.
基金supported by the Qi-Huang Chief Scientist Project of the National Administration of Traditional Chinese Medicine(2020).
文摘Phytochemical study of the n-BuOH extract of Ilex asprella resulted in the discovery of ten new pentacyclic triterpenoid glycosides,comprising nine ursane-type glycosides(1-9)and one oleanane-type glycoside(10),along with seven known compounds(11-17).Compound 1 is the first reported 19,22-epoxy ursane triterpenoid glycoside,whereas 4 and 5 are rare examples of ursane triterpenoid glycosides containing a 28,19-lactone group.The structural characterization of these compounds was achieved using spectroscopic and chemical techniques,as well as single-crystal X-ray analysis.Compounds 7,12,15,and 17 exhibited moderate cytotoxic activities against H1975 and HCC827 cancer cells.
基金supported by the Special Project for Marine Economic Development of Department of Natural Resources of Guangdong Province(No.GDNRC[2024]25)National Natural Science Foundation of China(Nos.82274002,U20A20101)+1 种基金Guangdong Local Innovation Team Program(No.2019BT02Y262)Science and Technology Innovation Project of Guangdong Medical Products Administration(Nos.S2021ZDZ042,2023ZDZ06,2024-ZDZ08,2024A1515012477)。
文摘This study investigates the pharmacokinetics and metabolic characteristics of three marinederived piericidins as potential drug leads for kidney disease:piericidin A(PA)and its two glycosides(GPAs),glucopiericidin A(GPA)and 13-hydroxyglucopiericidin A(13-OH-GPA).The research aims to facilitate lead selection and optimization for developing a viable preclinical candidate.Rapid absorption of PA and GPAs in mice was observed,characterized by short half-lives and low bioavailability.Glycosides and hydroxyl groups significantly enhanced the absorption rate(13-OH-GPA>GPA>PA).PA and GPAs exhibited metabolic instability in liver microsomes due to Cytochrome P450 enzymes(CYPs)and uridine diphosphoglucuronosyl transferases(UGTs).Glucuronidation emerged as the primary metabolic pathway,with UGT1A7,UGT1A8,UGT1A9,and UGT1A10 demonstrating high elimination rates(30%-70%)for PA and GPAs.This rapid glucuronidation may contribute to the low bioavailability of GPAs.Despite its low bioavailability(2.69%),13-OH-GPA showed higher kidney distribution(19.8%)compared to PA(10.0%)and GPA(7.3%),suggesting enhanced biological efficacy in kidney diseases.Modifying the C-13 hydroxyl group appears to be a promising approach to improve bioavailability.In conclusion,this study provides valuable metabolic insights for the development and optimization of marine-derived piericidins as potential drug leads for kidney disease.
文摘Anoectochilus roxburghii from different planting sources was used as the research object,and the biological activity of its extracts was compared.The results showed that the whole plant extracts of A.roxburghii planted in bag culture (BAG),greenhouse cultivation (GRE) and tissue culture seedlings (TIS) were rich in active ingredients such as A.roxburghii polysaccharides and A.roxburghii glycosides.In vitro experiments showed that Anoectochilus roxburghii extracts from different planting sources had good antioxidant capacity,tyrosinase inhibition ability and hyaluronidase inhibition ability.Among them,the GRE Anoectochilus roxburghii whole plant extract had the strongest scavenging ability on DPPH free radical,ABTS free radical and hydroxyl free radical,and the inhibitory effect on tyrosinase activity and hyaluronidase activity was significantly higher than that of BAG and TIS.At the same time,it also verified that the extract of Anoectochilus roxburghii has antioxidant,whitening,anti-inflammatory and other skin care effects,which provides a theoretical basis for the development and application of Anoectochilus roxburghii extract in the field of cosmetics.
基金supported by the National Natural Science Foundation of China(No.81874369)the Excellent Youth Project of the Hunan Provincial Department of Education(No.22B0388)the Project of Hunan Administration of Traditional Chinese Medicine(No.B2023143)。
文摘Five new flavan-4-ol glycosides jixueqiosides A-E(1-5)and two new flavan glycosides jixueqiosides F and G(6 and 7),along with twelve known flavan-4-ol glycosides(8-19),were isolated from the roots of Pronephrium penangianum.Comprehensive spectral analyses,X-ray single-crystal diffraction,and theoretical electronic circular dichroism(ECD)calculations established structures and absolute configurations.A single crystal structure of flavan-4-ol glycoside(14)was reported for the first time,while the characteristic ECD and NMR data for all isolated flavan-4-ol glycosides(1-5,8-19)were analyzed,establishing a set of empirical rules.Activity screening of these isolates showed that 8 and 9 could inhibit the proliferation of MDA-MB-231 and MCF-7 cells with IC50 values of 7.93±2.85μmol·L^(-1)and 5.87±1.58μmol·L^(-1)(MDA-MB-231),and 2.21±1.38μmol·L^(-1)and 3.52±1.55μmol·L^(-1)(MCF-7),respectively.Western blotting and flow cytometry analyses demonstrated that 8 and 9 dose-dependently induced apoptosis in MDA-MB-231 cells by up-regulating BAX,activating caspase-3 and down-regulating BCL-2.Additionally,compound 8 affected autophagy-related proteins,increasing the ratio of LC3-II/LC3-I and Beclin-1 levels to inhibit MDA-MB-231 cell proliferation.Moreover,anti-inflammatory studies indicated that 2,3,7,13,14,and 18 moderately inhibited tumor necrosis factor-α(TNF-α),interleukin-6(IL-6),and nitric oxide(NO)release.
基金supported by the Jiangsu Province University Basic Science(Natural Science)Research Major Project(24KJA360007)Nanjing University of Chinese Medicine TCM First-Class Discipline"Leading Plan"Scientific Research Project(ZYXYL2024-001)+3 种基金Jiangsu Provincial TCM Science and Technology Development Program Project(MS2021004)High Level Key Discipline Construction Project of the National Administration of Traditional Chinese Medicine-Resource Chemistry of Chinese Medicinal Materials(ZYYZDXK-2023083)National Administration of Traditional Chinese Medicine Chinese Medicine Innovation Team and Talent Support Program Project(ZYYCXTD-D-202005)2022 Student Innovation Training Program Project(103152022075).
文摘Food-derived polysaccharides are gaining popularity across diverse food applications due to their wideranging bioactivities and distinctive properties.The specific targeting of glycoside hydrolases towards glycosidic bonds lays the groundwork for synthesizing and exploring specific structural segments of polysaccharides,offering crucial implications in the food industry.However,macromolecular polysaccharides demonstrate limited biological activities as their active centers are tightly enveloped,posing challenges for traversing cell membrane barriers.By selectively cleaving partial glycosidic linkages in polysaccharides,glycoside hydrolases decrease the polymerization of polysaccharide molecules and effectively change the structural characteristics,where a series of smaller polysaccharide fragments can be generated for improving the bioactivities and properties in some respects.This review examines the role of glycoside hydrolases in degrading food-derived polysaccharides,the structure-function relationships,reaction conditions,and the current application status of degraded polysaccharides is discussed in particular.In addition,we also highlight challenges and future directions worth attention in the application of enzymes and polysaccharides.Overall,the present review will provide an efficient method for producing bioactivity-enhanced polysaccharides,which can improve the effectiveness and safety of functional foods to safeguard human wellness.
基金supported by grants from the National Natural Science Foundation of China(32460505)China Agriculture Research System(CARS-11)+2 种基金the Chinese Academy of Tropical Agricultural Sciences for the Science and Technology Innovation Team of the National Tropical Agricultural Science Center(CATASCXTD202301)Additional support was provided by the Hainan Province Graduate Innovation Research Project(Hyb2020-09)the Key Laboratory of Tropical Fruits and Vegetables Quality and Safety for State Market Regulation(KF-2023016).
文摘The high content of cyanogenic glycosides(CG)in cassava tubers affects food safety.CG are involved in the plant growth and development and protect cassava leaves from herbivorous predators.However,the regulatory mechanism of CG biosynthesis remains poorly understood.Here,yeast one-hybrid assays were performed using a mixed cDNA library of cassava tubers and leaves as prey and the promoter of MeCYP79D2 as bait.MeCYP79D2,a cytochrome P450 protein,is the rate-limiting enzyme for CG synthesis in cassava.From this information,a candidate regulator of MeCYP79D2 was selected and identified as transcription factor MePHD1.2.MePHD1.2,located in the nucleus and exhibiting an inhibitory transcription activity directly bound to an AT-rich motif in the promoter of MeCYP79D2.In cassava,the transcriptional activity of MeCYP79D2 was considerably enhanced in mephd1.2 mutant lines leading to increased linamarin and lotaustralin contents.Deletion of MePHD1.2 promoted the production of CGs in cassava and decreased transcription inhibition on MeCYP79D2,exposing a novel regulatory module governing biosynthesis of CGs.
文摘Abstract： In the present study, we established an ultra performance liquid chromatography coupled with time-of-flight mass spectrometry （UPLC-QTOF-MSE） method to simultaneously quantify 33 components in Ginkgo biloba leaf extracts （GBEs）, including 17 flavonol glycosides, five terpene trilactones （TTLs）, four polyphenols and seven carboxylic acids. This optimized method was successfully applied to analyze the explicit compositions of GBE samples collected from different places. Furthermore, the data were processed through unsupervised principal component analysis （PCA） and supervised orthogonal partial least squared discrimination analysis （OPLS-DA） to evaluate the quality and compare the differences between the samples according to the contents of the 33 chemical constituents. Bilobalide, protocatechuic acid, shikimic acid, quinic acid, ginkgolide B, ginkgolide J, kaempferol-3-O-rutinoside, isorhamnetin-3-O-rutinoside, quercetin-3-O-ct-L-rhamnopyranocyl-2＂-（6＇＂-p-coumaroyl）-β-D-glucoside and rutin were recognized as characteristic chemical markers that contributed most to control the quality of GBEs. Based on the fact that GBEs should be standardized with the characteristic components as quality control chemical markers, it is most important to maintain the quality of GBEs stable and reliable, and this method also provided a good strategy to further rectify and standardize the GBEs market.
文摘Aim To investigate the chemical composition of Ranunculus sieboldii Miq..Methods Repeated column chromatography over silica gel, polyamide and RP-18 followed by gelfiltration on sephadex LH-20 were used to isolate chemical constituents, and their structures wereelucidated by extensive spectroscopic methods (UV, IR, MS, ~1H NMR, ^(13)C NMR) including 2D NMR(COSY, HMQC, HMBC, NOESY) techniques and by direct comparing spectral data with those reported inliterature. Results Five flavonoid glycosides named apigenin-4'-O-α-L-rhamnopyranoside (1),apigenin-7-O-β-D-glucopyranosyl-4'-O-α-L-rhamnopyranoside (2), apigenin-8-C-α-L-arabinopyranoside(3), apigenin-8-C-β-D-ga-lactopyranoside (4) , tricin-7-O-β-D-glucopyranoside (5), together withtricin (6), luteolin (7), scopoletin (8), esculetin (9), scoparone (10), ferulic acid (11),protocatechuic acid (12) , and tematolide (13) were isolated from the 95% etha-nolic extract of itswhole plant, and their cytotoxic activities were preliminarily tested. Conclusion Compounds 1-12were obtained from this genus and compound 13 from this species for the first time. Furthermore,compound 1 was for the first time isolated from nature while the ^(13)C NMR data of compounds 2 and3 are reported for the first time. The bioassay revealed that compound 1 was active against BEL-7407and A549 cell lines (IC_(45) 43, 77 μg·mL^(-1)), 8 and 10 showed inhibitory activities on KB celllines (IC_(50) 78, 44 μg·mL^(-1)) and HL-60 cell lines (Ic_(50) 85, 85 μg·mL^(-1)), while 7exerted moderate cytotoxic activities on KB, BFL-7407, A549 and HL-60 cell lines with their IC_(50)being 51, 55, 44 and 10 μg·mL^(-1) , respectively.
文摘Parvifloside (1), a new furostanol pentaglycoside, was isolated from the fresh rhizomes of Dioscorea parviflora C. T. Ting. On the basis of spectroscopic and chemical methods, its structure was elucidated as (25R)-26-O-β-glucopyranosyl-furost-5-en-3β,22ξ,26-triol 3-O-β-D-glucopyranosyl (1→3)-β-D-glucopyranosyl (1→4)-[α-L-rhamnopyranosyl (1→2)]-β-D-glucopyranoside. Six prosapogenins (2-7)were obtained from the enzymatic degradation of 1by cellulase, but only 3 and 4 were obtained by β-glucosidase. The structures of all compounds were determined by spectroscopic data. The activity of the isolated compounds on deformation of mycelia germinated from Pyricularia oaryzae P-2b conidia was evaluated.
文摘Two new phenylpropanetriol glycosides, named as meliadanoside A (3 - methoxy- 5 - hydroxy-9- (1' - O-β-D-glucopyranosyl) - threo - phenylpropanetriol ) and meliadanoside B (4- hydroxy-7, 8- (2', 1' - O- β- D -glucopyranosyl) - phenylpropanetriol), were isolated from the water-soluble extract of the fruits of Meliatoosendan Sieb. et Zucc., along with threo-guaiacylglycerol. Their structures were elucidated by spectroscopic and chendcal analysis.
文摘Introduction The plants of genus Cistanche G. Beck, which belong to Orobanchaceae family, include about twenty species, and there are four species and one variety are distributed in the northwest part of China. The dried fleshy stem of Cistanche genus plant known as ＇Roucongrong＇ in Chinese traditional medicine, has long been used for kidney deficiency, female infertility, morbid leucorrhea, and neurasthenia. Studies on active components and pharmacological activities show that it possesses significant activities in enhancing potency, anti-fatigue, immuno-modulability, etc, and phenylethanoid glycosides are the major active components. Due to excessive exploitation, its natural resources are facing with exhaustion. In order to improve this situation, the plant has been cultivated on a large scale in the northwest part of China. Up to now, the chemical investigations of the cultivated Cistartcbe salsa have not been undertaken. In this paper we report seven phenylethanoid glycosides from the cultivated Cistanche salsa： echinacoside （1）, cistanoside A （2）, acteoside （3）, isoacteoside （4）, 2＇-acetylacteoside （5）, tubuloside B （6）, and eutigoside A （7）. Among them, compound 7 isolated fronl family Orobanchaceae was reported previously, and compounds 1, 2, 3, 4, 5 and 6 from the cultivated Cistanche salsa are reported for the first time.
基金Supported by Longyuan Young Creative Research Project(GSYS08-A05)Special Fund of Agricultural Science and Technology Innovation in Gansu Province(GSAS0919)~~
文摘[Objective] The paper was to study the effect of potato extract on its phenolic metabolism,SAGs accumulation and allelopathic autotoxicity.[Method] With water treatment as control,the effects of aqueous extracts of potato bud,leaf-stem and tuber on its morphological characteristics,phenolic metabolism,glycoside alkaloids accumulation and allelopathic autotoxicity were studied.[Result] After the treatment of aqueous extract,the germination rate of potato reduced,germination was delayed,the plants became smaller,and the growth of root slowed down;the content of phenolic substances in roots,stems and leaves of potato increased,glycoside alkaloids accumulated,the activity of PPO and PAL increased.The effects of aqueous extract treatment on germination,growth,phenolic metabolism,glycoside alkaloid content and allelopathic autotoxicity successively were bud extractleaf-stem extracttuber extractcontrol.Treatment of aqueous extract did not affect the distribution of phenolic substances and glycosidic alkaloid in potato.[Conclusion] Phenolic substances and glycosidic alkaloid involved in the allelopathic autotoxicity of aqueous extract of potato,which had inhibition effect on germination and growth of potato.
