Total flavonoids of Astragalus membranaceus protect against 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine-induced neurotoxicity in mice by inhibiting ferroptosis through SLC7A11/GPX-4 signaling pathway

Parkinson’s disease(PD)is a common neurodegenerative disorder with no cure.Astragalus membranaceus is used in Chinese culture as a food supplement to boost immunity.The present study aimed to explore the neuroprotective effects of total flavonoids extracted from A.membranaceus(TFA)and their protective mechanisms.TFA offered neuroprotection against 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine(MPTP)in the mouse model of Parkinsonism,by improving behavior performance in the gait analysis and pole test,and inhibiting the decline of tyrosine hydroxylase(TH)positive neurons and TH protein expression in substantia nigra of mice.TFA also prevented 1-methyl-4-phenylpyridinium(MPP+)induced neurotoxicity in SHSY5Y cells,by increasing GSH and GSH/GSSG ratio,and reducing reactive oxygen species.In addition,the neuroprotective effects of TFA were associated with its ability to restore MPTP/MPP+induced downregulation of SLC7A11 and glutathione peroxidase 4(GPX-4).In conclusion,we demonstrated that TFA exerted significant neuroprotection against MPTP/MPP+induced neurodegeneration by inhibiting ferroptosis through the regulation of SLC7A11/GPX-4 axis,suggesting the use of TFA as a possible food supplement in the prevention of PD.

Astragalus membranaceus(Fisch.)Bge.administered by dissolving microneedles achieves systemic therapeutic effects at low doses Author links open overlay panel

Objective To determine the main components of Astragalus membranaceus(Fisch.)Bge(A.membranaceus,Huang Qi),Astragaloside IV(AIV)and Astragalus polysaccharides(AP),to characterize their properties,evaluate their in vivo efficacy,and to analyze drug diffusion using dissolving microneedle(DMN)technology in vivo.Methods Respectively,AIV-and AP-loaded DMNs comprising chitosan(CTS)and polyvinyl alcohol(PVA)were prepared via dual-mold forming.Their morphology,mechanical properties,in vivo solubility,and skin irritation characteristics were tested.In vivo efficacy was assessed in cyclophosphamide-induced immunosuppressed mice,in vivo diffusion of AIV and AP by DMNs and conventional methods was compared,and the rheological properties of AIV-CTS-PVA and AP-CTS-PVA mixtures were measured.Results Subcutaneous dissolution and absorption of AIV-CTS-PVA and AP-CTS-PVA microneedles(MNs)at low doses(50%–17%of intraperitoneal AIV injection and 12%–4%of intravenous AP injection)reduced the spleen index and acid phosphatase activity in immunosuppressed mouse models,increased the thymus index,and achieved equivalent or better systemic therapeutic effects.Compared with injections,AIV and AP achieved controllable solid-liquid conversion through delivery with CTS-PVA MNs,resulting in highly localized aggregation within 48 h,reducing the initial explosive effect of the drug,and achieving stable and slow drug release.Conclusion The present study enhances our understanding of the efficacy and remote effects of drug-loaded DMNs from a traditional Chinese medicine(TCM)perspective,thereby promoting the development of precise and efficient delivery of TCM and further expanding the drug-loading range and application scenarios for DMNs.

Network pharmacology and molecular dynamics study of the effect of the Astragalus-Coptis drug pair on diabetic kidney disease

BACKGROUND Diabetic kidney disease(DKD)is the primary cause of end-stage renal disease.The Astragalus-Coptis drug pair is frequently employed in the management of DKD.However,the precise molecular mechanism underlying its therapeutic effect remains elusive.AIM To investigate the synergistic effects of multiple active ingredients in the Astragalus-Coptis drug pair on DKD through multiple targets and pathways.METHODS The ingredients of the Astragalus-Coptis drug pair were collected and screened using the TCMSP database and the SwissADME platform.The targets were predicted using the SwissTargetPrediction database,while the DKD differential gene expression analysis was obtained from the Gene Expression Omnibus database.DKD targets were acquired from the GeneCards,Online Mendelian Inheritance in Man database,and DisGeNET databases,with common targets identified through the Venny platform.The protein-protein interaction network and the“disease-active ingredient-target”network of the common targets were constructed utilizing the STRING database and Cytoscape software,followed by the analysis of the interaction relationships and further screening of key targets and core active ingredients.Gene Ontology(GO)function and Kyoto Encyclopedia of Genes and Genomes(KEGG)pathway enrichments were performed using the DAVID database.The tissue and organ distributions of key targets were evaluated.PyMOL and AutoDock software validate the molecular docking between the core ingredients and key targets.Finally,molecular dynamics(MD)simulations were conducted to simulate the optimal complex formed by interactions between core ingredients and key target proteins.RESULTS A total of 27 active ingredients and 512 potential targets of the Astragalus-Coptis drug pair were identified.There were 273 common targets between DKD and the Astragalus-Coptis drug pair.Through protein-protein interaction network topology analysis,we identified 9 core active ingredients and 10 key targets.GO and KEGG pathway enrichment analyses revealed that Astragalus-Coptis drug pair treatment for DKD involves various biological processes,including protein phosphorylation,negative regulation of apoptosis,inflammatory response,and endoplasmic reticulum unfolded protein response.These pathways are mainly associated with the advanced glycation end products(AGE)-receptor for AGE products signaling pathway in diabetic complications,as well as the Lipid and atherosclerosis.Molecular docking and MD simulations demonstrated high affinity and stability between the core active ingredients and key targets.Notably,the quercetin-AKT serine/threonine kinase 1(AKT1)and quercetin-tumor necrosis factor(TNF)protein complexes exhibited exceptional stability.CONCLUSION This study demonstrated that DKD treatment with the Astragalus-Coptis drug pair involves multiple ingredients,targets,and signaling pathways.We propose a novel approach for investigating the molecular mechanism underlying the therapeutic effects of the Astragalus-Coptis drug pair on DKD.Furthermore,we suggest that quercetin is the most potent active ingredient and specifically targets AKT1 and TNF,providing a theoretical foundation for further exploration of pharmacologically active ingredients and elucidating their molecular mechanisms in DKD treatment.

Extraction of Astragalus Polysaccharides and Ganoderma lucidum Mycelia Polysaccharides and Their in Vitro Antioxidative Effects

[Objectives]To explore the extraction and in vitro antioxidant effects of astragalus polysaccharides(APS)and Ganoderma lucidum mycelia polysaccharides(GLMPS).[Methods]By studying the polysaccharides of the herbal medicinal material Astragalus membranaceus and the fungal medicinal material Ganoderma lucidum mycelia,two polysaccharides were mixed according to different proportions and concentrations by using the principle of traditional Chinese medicine compound combination.The effect of polysaccharides on the scavenging ability of hydroxyl radical system was determined by salicylic acid method.[Results]When the compound ratios of GLMPS and APS were 1∶1,1∶4,1∶5,4∶1,and 5∶1,the scavenging effect of compound polysaccharides was better than that of single-component polysaccharides,and with the increase of concentration,the scavenging effect increased.When the ratio of GLMPS and APS was 5∶1,the hydroxyl radical scavenging rate of the compound polysaccharide reached 59.77%,which was 18.72%higher than that of single GLMPS and 28.58%higher than that of single APS.The scavenging effect of compound polysaccharide is closely related to the compound ratio and concentration.[Conclusions]APS and GLMPS can obtain better hydroxyl radical scavenging ability than single-component polysaccharides through compounding in appropriate proportions.In addition,within a suitable concentration range,as the concentration increases,the scavenging ability also increases.

Astragalus adscendens extract shows antidiabetic effects through controlling oxidative stress,inflammation and apoptosis in streptozotocin-induced diabetic rats

Objective:To assess the effect of oral treatment of methanolic extract of the aerial parts of Astragalus adscendens in streptozotocin-induced diabetic rats.Methods:In order to induce diabetes,rats intraperitoneally received streptozotocin at 65 mg/kg.Sixty adult male Wistar rats were allocated into six groups(10 rats per each)including the healthy control group,the diabetic group as well as the diabetic group treated with Astragalus adscendens methanolic extract at 50,100,and 200 mg/kg per day or glibenclamide(0.6 mg/kg/day)for 28 d.The effects of Astragalus adscendens methanolic extract on the levels of glucose,insulin,alanine aminotransferase,alkaline phosphatase,aspartate aminotransferase,bilirubin,creatinine,urea,uric acid,total protein,albumin,triglyceride,cholesterol,α-amylase,oxidant/antioxidant enzymes,and inflammatory cytokines were evaluated.Real time-PCR was also used for measuring the gene expression of caspase-3,Bcl2,and Bax.Results:The levels of glucose,cholesterol,triglyceride,creatinine,urea,uric acid,alanine aminotransferase,aspartate aminotransferase,alkaline phosphatase,bilirubin,and malondialdehyde considerably declined(P<0.001)in diabetic rats after treatment with Astragalus adscendens methanolic extract especially at a dose of 200 mg/kg.In addition,treatment with Astragalus adscendens methanolic extract noticeably increased the level of insulin,total protein,and albumin as well as improved the activities of catalase,glutathione peroxidase,and superoxide dismutase,as well as the expression levels of TNF-α,IL-1β,caspase-3,Bcl2 and Bax(P<0.001)compared to the diabetic control group.The extract also inhibitedα-amylase in a dose-dependent manner with an IC_(50)value of 19.6μg/mL.Conclusions:Astragalus adscendens methanolic extract shows potent antidiabetic,anti-inflammatory,anti-apoptotic,and antioxidant effects in diabetic rats.However,more studies are needed to verify the underlying mechanism of the effect of this plant extract and test its efficacy in clinical trials.

Green synthesis,characterization,acaricidal,larvacidal,and repellent activities of copper nanoparticles of Astragalus sinicus against Hyalomma anatolicum

Objective:To green synthesize and characterize copper nanoparticles(Cu NPs)using Astragalus sinicus,as well as evaluate the acaricidal,larvacidal,and repellent activities of Cu NPs against Hyalomma anatolicum(H.anatolicum),one of the most prevalent ticks infesting cattle in Saudi Arabia.Methods:Cu NPs were green synthesized by adding the Astragalus sinicus extract to a copper sulfate solution.The acaricidal,larvicidal,and repellent activities of Cu NPs against H.anatolicum were assessed via the adult immersion test,the larval packet test,and the vertical movement behavior of tick larvae,respectively.The effects of Cu NPs on acetylcholinesterase as well as oxidative enzyme activities were examined.Results:The green synthesized Cu NPs displayed a spherical form with a size range of 15-75 nm.After exposure of adult H.anatolicum to different concentrations of Cu NPs,the viability rate of adult H.anatolicum and the mean number,weight,and hatchability of eggs were noticeably reduced,in comparison to the control group(P<0.001).In addition,the viability rate of larvae considerably declined(P<0.001)with the LC_(50)and LC_(90)values of 11.30 and 20.34μg/m L,respectively.The maximum repellent activity of Cu NPs was observed at 50,100,and 200μg/m L with complete repellent activity after 60,120,and 180 min of exposure,respectively.Cu NPs,mainly at 1/2 LC_(50)and LC_(50)concentrations,markedly suppressed the acetylcholinesterase activity of the larval stage of H.anatolicum(P<0.001).Moreover,Cu NPs,mainly at LC_(50)dose,significantly elevated malondialdehyde level while declining glutathione-S-transferase level in H.anatolicum larvae(P<0.001).Conclusions:Cu NPs show potent acaricidal,larvicidal,and repellent activities against adults and larvae of H.anatolicum.However,further studies must be performed to clarify the precise mechanisms and the efficacy of Cu NPs in practical use.

Effects of Astragalus membranaceus on Energy Metabolism and Expression of CNTF Protein in Skeletal Muscle of Exercise-induced Fatigue Rats

[Objectives]This study was conducted to investigate the effects of Astragalus membranaceus in different groups on energy metabolism and CNTF protein expression in skeletal muscle of exercise-induced fatigue rats.[Methods]Thirty-five clean male SD rats were randomly divided into a normal group,and low-,meddle-and high-dose groups of A.membranaceus aqueous solution,with 7 rats in each group.The low-dose,medium-dose and high-dose groups were given by gavage at 0.65,1.3 and 2.6 g/kg,respectively,while the normal group and the model group were given normal food and water.The weight of rats was observed.The contents of serum urea,lactate,muscle glycogen,liver glycogen and CNTF expression were detected.[Results]After modeling,compared with the normal group,the serum lactate and urea contents of rats in the model group significantly increased(P<0.01),while the muscle glycogen content(P<0.01)and liver glycogen content(P<0.05)of the skeletal muscle significantly decreased.Compared with the model group,the low-,meddle-and high-dose groups of A.membranaceus significantly reduced the levels of lactate and urea in serum(P<0.01),while the levels of muscle glycogen and liver glycogen in the skeletal muscle significantly increased(P<0.01,P<0.05).[Conclusions]This study provides a good research foundation for the treatment of exercise-induced fatigue using traditional Chinese herb A.membranaceus in modern clinical practice.

Mechanism prediction of Astragalus mongholicus Bunge and Angelica sinensis Diels in treating interstitial lung disease based on network pharmacology and molecular docking

Objective:To investigate the mechanism by which Astragalus mongholicus Bunge(AM),and Angelica sinensis Diels(AS)act in interstitial lung disease(ILD)based on computational prediction.Methods:We screened the ingredients of AM and AS in PubMed,the Web of Science,China National Knowledge Infrastructure(CNKI)Databases,etc.Then obtained the potential effective components.By sharing the same molecular with ILD,we got the possible target genes for ILD treatment and constructed components–targets–disease network with Cytoscape software.The CTD(Comparative Toxicogenomics Database)database was used for GO and KEGG enrichment analysis of these target genes.Results:59 active ingredients that can be druggable were chosen from AM,67 active ingredients were chosen from AS.77 overlapping target genes for AM and ILD and 36 overlapping target genes for AS and ILD were acquired.The hub targets of AM were PTGS2,PTGS1,CDK2,MAOA,ESR1,TOP2A,GSK3B,ESR2,PPARG,NOS2,The hub targets of AS were PTGS2,GABRA1,PTGS1,CHRM1,SLC6A2,ADRA1B,ADRAIA,ADRB2,CHRM3,GABRA2,CHRM2.Quercetin,kaempferol,daidzein,pavilion,7-Hydroxycoumarin,and 5-Hydroxycoumarin were the main active ingredients which have more effective targets.Prediction of the protein-protein interaction network showed PTGS2,GSK3B,PPARG,etc.,were the important predicted targets.The enriched KEGG pathways,including the Immune System,Metabolism of lipids and lipoproteins,Cytokine Signaling in the Immune system,Generic Transcription Pathway,The interleukin pathway,Metabolism of proteins,PI3K-Akt signaling pathway,Metabolic pathways,Innate Immune System,Neuroactive ligand-receptor interaction,Metabolism,GPCR downstream signaling,Amine ligand-binding receptors,Class A/1,Calcium signaling pathway.Molecular docking showed that quercetin,kaempferol,daidzein,pavilion,7-Hydroxycoumarin,5-Hydroxycoumarin had good binding activities with PTGS2 and GSK3B,which mainly mediated PI3K/Akt and other important signaling pathways in the pathogenesis of ILD.Conclusion:The components in AS and AM share some common targets,such as PTGS2.AM and AS may ameliorate ILD through the PI3K-Akt signaling pathway which is mediated by GSK3B.PTGS2,PPARG may also be vital target genes in the treatment of ILD with AM and AS.

A Preliminary Phylogenetic Study of the Subgenus Pogonophace ( Astragalus ) in China Based on ITS Sequence Data

The internal transcribed spacers (ITS) (including ITS1, 5.8S rRNA gene and ITS2) of Caragana roborovskyi and eight species of subgenus Pogonophace ( Astragalus) were sequenced, and analyzed together with other ITS data (from GenBank) of 48 species representing Astragalus and 12 related genera. The results of phylogenctic analyses suggest that the subgenus Pogonophace is not a monophyletic group. Sect. Sesbanella (Astragalus hoantchy and A. dshimensis) and other species of Pogonophace are nested within different major clades in the phylogenetic tree. The species of sections Bibracteola, Phyllolobium and Trichostylus compose a monophyletic group with a close relationship to subtribe Coluteinae instead of Astragalus. Astragalus tribulifolius and A. tanguticus might be a vicariant species pair as inferred by the ITS data.

ISOFLAVONES FROM ASTRAGALUS MEMBRANACEUS

Two new isoflavones (8, 3'-dihydroxy-7,4'-dimethoxyisoflavone, odoratin-7-0-[3-D-glu-copyranoside) and four known isoflavones (formononetin, 7,3'-dihydroxy-8,4'-dimethoxyisoflavone, calycosin, calycosin-7-0-(3-D-glucopyranoside) were isolated from the roots of Astragalus mem-branaceus (Fisch.) Bunge. Their structures were established by spectral analysis.

Genetic Variability of Astragalus sinicus L. Based on ISSR Markers

Genetic relationships among 22 accessions of Astragalus sinicus L. col ect-ed from different provinces of China were analyzed by inter-simple sequence repeat （ISSR） markers. The results showed that 10 highly reproducible ISSR fragments a-mong 40 primers were screened. Using these primers, a total of 684 ISSR frag-ments from 500 to 3 000 bp were amplified, and 59.2% of them showed polymor-phic by unweighted pair-group method with arithmetic （UPGMA） analysis. It revealed that the 22 accessions had a similarity range from 0.63 to 0.95, and existed biolog-ical diversities. Based on cluster and principal coordinate analyses, al accessions could be divided into four distinct groups.

Study on Pollinating Insects of Astragalus membranaceus (Ficsh) Bunge

[Objective The aim was to study species and pollinating characters of Astragalus membranaceus(Ficsh)Bunge pollinating insects and lay a theory foundation for the breeding of Astragalus membranaceus(Ficsh)Bunge.[Method] With Astragalus membranaceus(Ficsh)Bunge as research object,the species of pollinating insect and pollination behavior were investigated.[Result] There were 16 pollinating insect species,among which,Bombus ignitus,Bombus lucoru,Apis sp.,Betasyrphus serarius(wiedemann)and Colias erate(Esper)we...

Adaptability Comparison of Chinese Milk Vetch (Astragalus sinicus) Varieties for Double-rice Cropping System in Hunan

Five Chinese milk vetch（Astragalus sinicus） varieties were selected to make a comparison in order to screen effective varieties which could suit for the double-rice cropping system of Hunan Province. The results showed that the growth period of Xiangzi 2 is shorter than that of Xiangfei 2, Xiangfei 3 and Yujiangdaye,and is similar to that of Xinyang Chinese milk vetch. The full-bloom stage of Xiangzi 2 is also similar to Xinyang variety and obviously earlier than that of the other three varieties. The fresh grass yield of Xiangzi 2 in full-bloom stage is 23 842.5kg/hm^2, which increases by 39.9% compared with Xinyang variety. Nitrogen content in the fresh grass of Xiangzi 2 is higher than that of the other four varieties. In conclusion, Xiangzi 2 is an extremely early-blossoming and early-maturing Chinese milk vetch variety with moderate fresh grass yield, high nutrient contents, stable characters and wide adaptability. So, Xiangzi 2 is suitable for planting in double-rice cropping region in Hunan Province and other same latitude regions which have similar ecological conditions.

沙打旺(Astragalus adsurgens Pall cv.)单细胞培养再生植株

切取沙打旺无菌苗下胚轴接入固体M5培养基(MS+0.2 mg/1生物素+1 mg/1泛酸钙+1 mg/1 2,4-D+0.7 mg/1 BA+0.2 mg/l NAA)上形成愈伤组织,选用褐绿相间的愈伤组织放入液体CM2培养基(M5+1.3 g/l“1640”)中振荡暗培养。每隔15天换一次液,经过4次换液,用400目网过滤得到大量单细胞。取出单细胞进行双层静止暗培养,每隔7—10天加一次液,一个半月形成小块愈伤组织。然后转入固体M5培养基中增殖,20天形成大块愈伤组织,再转入分化培养基MF2(M5去掉2,4-D)中,一个月左右分化出苗,将苗转入生根培养基,长成完整植株。

重离子及电子辐照沙打旺(Astragalus Adsurgens Pall)干种子的辐射生物学效应

本文采用80MeV/u12C6+和50keV的电子辐照沙打旺干种子,研究沙打旺干种子不同注量的辐照生物学效应,检测其生理生化指标。结果表明:无论是碳离子辐照还是电子辐照,发芽势都随注量的增加先升高后降低,发芽率都随注量增加逐渐降低。其次,碳离子辐照样品,其超氧化物歧化酶(SOD)、谷胱甘肽过氧化物酶(GSH-Px)活性变化随注量增加先升高后降低,即存在一个峰值,过氧化氢酶(CAT)在高于5×106ions/cm2注量的离子辐照中其活性基本不发生变化;不同注量的电子辐照,样品的CAT、SOD、GSH-Px活性都是先升高后降低。第三,无论是碳离子辐照还是电子辐照样品的谷胱甘肽(GSH)含量变化不显著,与注量的变化没有明显的相关性。总而言之,本工作发现碳离子及电子辐照样品,其多个生理生化指标均随注量的增加呈先升高后降低的趋势,但GSH变化对碳离子或电子辐照都不敏感。

Effects of Astragalus Powder on Serum Lipid and Body Fat Content of Fast Large-scale Quality Chickens

[ Objective] To study the effects of astragalus powder on serum lipids and body fat contents of fast large-scale quality chickens, and thus provide a theoretical basis for its application in poultry production,[ Method ] All the 180 1-day-old healthy Liangfeng chickens were randomly divided into six groups. Group 1 was the control group, fed with basal diet; group 2, group 3 and group 4 were fed with basal diet added with 0.75%, 1.0% and 1.25% astragalus powder, respectively; group 5 and group 6 were separately fed with basal diet added with 1.0% and 1.25% astragalus pow- der, but the astragalus powder was used for 10 d and then was forbidden for 10 d in turn during the whole experiment. The content of triglyceride （TG）, total cholesterol （TCHO）, high-density lipoprotein-Cholesterol （ HDL-C）, and low-density lipoprotein-Cholesterol （LDL-C） were respectively determined when the chickens were 35-day-old and 63-day-old, while the percentage of abdominal fat （PAF） as well as intramuscular fat （IMF） and subcutaneous fat ply （SFP） was measured when the chickens were 63-day-old. [ Result] In 35-day-old chickens, the levels of TCHO were sig- nificantly or very significantly lower in group 3, group 4, and group 6 than in control group （ P 〈0.05 or 0.01 ） ; the levels of LDL-C significantly lower in group 3 and group 6 （ P〈0. 05） ; the level of HDL-C significantly higher in group 5 （P〈0.05）. In 63-day-old chickens, the levels of TCHO and LDL-C were significantly or very significantly lower in group 3, group 4, and group 5 than in control group （ P 〈 0.05 or 0.01 ） while the levels of HDL-C were significantly higher in these groups; the PAF was significantly lower in group 3 （ P 〈 0.05）. [ Condasion] Astragalus powder should re- duce the levels of TG, TCHO and LDL-C, promote HDL-C content, and also play a certain regulative role in deposition of abdominal fat.

Study on Tissue Culture and Radiation Mutation of Astragalus membranaceus Bge. var. mongholicus(Bge.) Hsiao

[Objective] The research aimed to study the tissue culture technology and callus induction by radiation mutation of A. membranaceus Bge. [ Method ] With the different parts of Astragalus membranaceus Bge. var. mongholicus （ Bge. ） Hsiao aseptic seedling as explants （ leaves, cotyledons, hypocotyls） induced callus, and cotyledon and hypocotyls taken by the method of radiation mutation were studied. [ Result]The results showed that the three explants had relatively high callus induced rate in the medium which respectively made up of MS ＋6-BA 2.0 mg/L ＋ NAA2.0 mg/L, LS ＋6-BA2.0 mg/L ＋NAA0.1 mg/L, MS ＋ 6-BA2.0 rng/L ＋ NAA2.0 rag/L; the optimum mutation time of hypocotyls and cotyledons was 15 minutes; the growth of the callus induced from hypocotyls would be better as the mutation time increased, but when it reached a certain time the growth would be weaken, the induction rate also would be reduced. [ Conclusion] This study will provide the scientific reference in tissue culture and mutation breeding of A. membranaceus Bge.

细叶黄芪(Astragalus tenuis)单细胞培养高频率再生植株

本研究建立了一套适合于细叶黄芪单细胞悬浮培养的良好系统.在该培养系统中,细叶黄芪单细胞高频率地再生了完整植株.由细叶黄芪种子无菌苗茎段诱导产生的愈伤组织建立了细胞悬浮系.从悬浮系分离的单细胞悬浮培养2～3天开始分裂,35天形成大量的小愈伤组织.小愈伤组织继续悬浮培养即可不断地分化出大量幼芽.愈伤组织在固体分化培养基上的分化率为100％.目前已获得了大量的再生植株.本文还就2,4—D对细叶黄芪和细胞培养的影响进行了讨论.

Cellulase Extraction and Gas Chromatography Detection Technology of Swainsonine from Astragalus strictusin in Tibet

Locoweed is a poisonous plant wildly distributed in most areas of the world,which causes livestock poisoning or death with serious economic loss.The Astragalus strictus belongs to a species of Iocoweed.It is mainly distributed in Tibet of China and is a serious hazard to the local livestock industry.The objective of this study is extracting and purifying condition of Swainsonine from Astragalus strictus with the cellulase extraction method.An optimum extracting technology of SW from Astragalus strictus was investigated through the orthogonal experiment under the cellulose assistance conditions,and then the content of swainsonine was analyzed with gas chromatography （GC） method.The optimized extraction conditions were as follow：The crushed mesh is 40; solid-liquid ratio is 1∶40 （g/ml）; enzyme dosage is 3.5％; enzymatic time is 3 h.Under the above conditions,the extraction percentage of the swainsonine was 0.003 941％.The conditions for extracting swainsonine with cellulase extraction method are mild,it is easy to utilize industrial production.It is benefit for producing swainsonine from Astragalus strictus.

Effects of Ploughing Astragalus sinicus at Maturity Stage on Rice Yield and Soil Properties of Paddy Field

[Objective] The effects of ploughing Astragalus sinicus at maturity stage as green manure on paddy soil properties were studied to provide references for ad- vancing the green manure production and field sustainable development. [Methods] A three-year field positioning experiment was carried out. In the first year, five differ- ent levels （0, 2.81, 5.61, 8.42, 11.23 t/hm~） of Astragalus sinicus ploughed at matu- rity stage were designed. And in the next two years, the amounts of ploughed As- tragalus sinicus at maturity stage were based on the natural growth amounts of As- tragalus sinicus at maturity stage of the former year in each plot field. The yields of Astragalus sinicus at maturity stage were estimated and ploughed directly before rice transplanting. Rice yield, soil nutrients, biological properties and water-stable aggre- gates of paddy fields were measured as well. [Results] The effective panicles and rice yields increased significantly after ploughing Astragalus sinicus at maturity stage. Meanwhile, the organic acid content in paddy field increased and the activities of soil phosphatases, invertase and catalase were higher. The soil dissolved organic carbon also increased with the increasing application of green manure. However, excess amount of green manure inhibited the soil microbial biomass carbon content. The macro aggregates and micro aggregates gathered to middle aggregates. [Conclusion] As green manure, the use of Astragalus sinicus at maturity stage could improve soil physiochemical and biological properties, improve soil fertility and increase rice yield significantly. But the ploughing amount of Astragalus sinicus at maturity stage before rice transplanting should be less than 8.42 t/hm2 （dry weight.