The Quantitative Analysis and Identification of Steroidal Sapogenins of the Dioscorea Plant

The results for the quantitative analysis and identification of steroidal sapo-genins of 16 species of Dioscorea rhizomes are given in Table 1. The amount of steroidal sapogenin varies from 0.073%–5.93%, its highest content of diosgenin is 5.93% in D. zingiberensis C. H. Wright. 2. The results observed from paper chromatography, thin layer chromatography and gas-liquid chromatography revealed that except the sapogenin of D. chingii Pr. and Br. is similar to tokorogenin, all other sapogenins after recrystallization yield a spot identical to diosgenin or yamogenin. Meanwhile, in most Dioscorea sample, a spot identical to △ 3, 5-diene-25D-spirostane was shown by using thin layer chromatography and gas-liquid chromatography. (Table 2). 3. The results observed from infrared spectrum and gas-liquid chromatography revealed that the sapogenins of D. collettii, Hook. f; D. collettii. Hook, f. var. hypoglauca, Pei and Ting. and D. tokoro Makino. contained 25L-spirostane. (A900≤ A920 cm-1).     

Isolation and Identification of Steroidal Saponins from Dioscorea parviflora Ting

Four steroidal saponins were isolated from rhizomes of Dioscorea parvi- flora Ting collected from Yunnan Province. Their chemical structures have been elucidated by means of chemical and spectrometric analyses as gracillin [Ⅰ]; deltonine [Ⅱ]; protogracillin [Ⅲ] and deltoside [Ⅳ]. Deltoside is the first time obtained in pure state from Dioscorea plants.     

The Identification and Isolation of Steroidal Saponin from Dioscorea gracillima Miq.

Two trisaecharides of diosgenin (A, B) had been isolated from the rhizome of Dioseorea gracillima Maq. (collected from Jiangsi, Lu Shan). By means of acetylafion, acid hydrolysis, IR, MS and 13C-NMR etc. saponin A and saponin B were identifieated as dioscin and gracillin, respectively. Its yieldingratio is 3:1 (A:B).     

Isolation and Identification of Steroidal Saponins from Dioscorea panthaica Prain et Burkill

Two steroidal saponins have been isolated from the rhizomes of Dioscorea panthaica Prain et Burkill. collected from Sichuan province. They were identified as 3-0-{α-L- rhamnopyranosyl (1→4)- [α-L-rhamnopyranosyl (1→2) ]-β-D-glucopyranosyl } -diosgenin (dioscin) and 3-O-{β-D-glucopyranosyl (1→3)-[α-L-rhamnopyranosyl (1→2)]-β-D-glucopyranosyl}-diosgenin (gracillin) on the basis of mp., m. mp., TLC. acetylation, acid hydrolysis, IR, MS, and 13C NMR.     

Identification and Isolation of Steroidal Saponins of Dioscorea zingiberensis Wright

Two diosgenin trisaccharides (A,B) and two furostanolic tetrasacharides of diosgenin (C, D) had been isolated from Dioscorea zingiberensis wright. By means of acetylation, acid hydrolysis, enzymolysis, IR, MS, 1H-NMR and 13C-NMR, saponin A was proved to be a new compound of structure: diosgenin-3-O- [ β-D-glucopyranosyl (1 → 2) ]-O- [ α-L-rhamnopyra- nosyl (1→3)]-O-β-D-glucopyranoside was provisionally named zingiberenin A; saponin B may be suggested as the steric isomer of gracillin; saponin C was identified as 26-O-β-D- glucopyranoside of A and saponin D as 26-O-β-D-glucopyranoside of B. The last two components named proto-zingiberenin A and proto-zingiberenin B respectively.     

弯蕊开口箭中的多羟基甾体皂甙元

从弯蕊开口箭(Tupistra wattii Hook. f.)的新鲜根茎中分离出2个新的多羟基甾体皂甙元,分别命名为弯蕊皂甙元B (wattigenin B) (1) 和弯蕊皂甙元C (wattigenin C) (2), 同时分离到2个已知的甾体皂甙元--凯替皂甙元kitigenin (3)和铃兰皂甙元B (convallagenin B) (4).通过波谱解析鉴定了这4个皂甙元的结构,并测定了它们在体外对肿瘤细胞K562和A2780a的细胞毒活性.化合物1～4为首次从该种植物中分离得到.     

弯蕊开口箭中的多羟基甾体皂甙元

从弯蕊开口箭(Tupistra wattii Hook．f．)的新鲜根茎中分离出2个新的多羟基甾体皂甙元,分别命名为弯蕊皂甙元B(wattigenin B)(1)和弯蕊皂甙元C(wattigenin C)(2),同时分离到2个已知的甾体皂甙元——凯替皂甙元kitigenin(3)和铃兰皂甙元B(convallagenin B)(4)。通过波谱解析鉴定了这4个皂甙元的结构,并测定了它们在体外对肿瘤细胞K562和A2780a的细胞毒活性。化合物1～4为首次从该种植物中分离得到。     

Isolation and Indentification of Steroidal Saponins from Dioscorea zingiberensis Wright

Four known steroidal compounds were isolated from the rhizomes of Dioscorea zingiberensis Wright gathered from Hubei Province. Their structures were identified by means of spectroscopic analyses as Epi-smilagenin[Ⅰ]; 3-O-(β-D glucopyranosyl) diosgenin[Ⅱ]; 3-O-[β-D-glucopyranosyl (1→ 4)-β-D-glucopyranosyl-diosgenin[Ⅲ]; 3-O {β-D glucopyranosyl (1→ 3)-[α-L-rhamnopyranosyl (1 →2)]-β-D glucopyranosyl} diosgenin [Ⅳ].     

The Effect of Photoperiod on Steroidal Sapogenins and other Constituents in Dioscorea deltoidea Wall

Dioscorea vines were cultured under different light periods(viz. 18 h light and 6 h darkness and vice versa), for 3 monthsand the effects on the composition and percentage of steroidalsapogenins present, at different stages of growth, were studied. Total sapogenins from different parts of the vine were estimatedat different times and it was found that the percentage of theseincreased in leaves and tubers during growth as also did theamount of phenolic components. New information regarding the nodal ganglion (nodal plexus)is brought to light, namely that this complex glandular tissueappears to be a seat of bio-chemical synthesis. Nodal gangliahave been analysed at different growth phases of the vine andthe amounts of different constituents recorded.     

Cholestane and spirostane glycosides from the rhizomes of Dioscorea septemloba

Cholestane glycosides, dioseptemlosides A (1) and B (2), together with six spirostane glycosides, dioseptemlosides C-H (3-8), were isolated from the rhizomes of Dioscorea septemloba. Their structures were established on the basis of physical data, spectroscopic analysis (HRESIMS, 1D and 2D NMR), and chemical methods. Spirostane aglcones containing hydroxyl group at C-7, as found in compounds 4-7, were reported in the family Dioscoreaceae for the first time. These compounds did not show considerable inhibitory anti-tumor activities at a concentration of 10 microM.     

Isolation and Identification of Steroidal Saponins and Sapogenins from Aspidistra zongbayi K. Y. Lang et Z. Y. Zhu

Two steroidal saponins were isolated from the n-BuOH extract of the rhizome of Aspidistra zongbayi K. Y. Lang et Z. Y. Zhu. Their structures were elucidated as 3-O-{β-D-glucopyr-anosyl (l→2)-[β-D-xylopyranosyl (1→3)]-β-D-glucopyranosyl (l→4)-β-D-glactopyranosyl}-diosgenin (aspidistrin) and proto-aspidistrin by physical and chemical methods. Three steroidal sapogenins were isolated from the acid-treated n-BuOH extract. They were identified as△3.5 deoxyfigogenin, diosgenin and gentrogenin, β-sitosterol was isolated from the rhizome of this plant also.     

Studies on the Steroidal Saponins of Dioscorea tokoro Makino Collected from Zhejiang

Six steroidal saponins were isolated from rhizome of Dioscorea tokoro Makino (collected from Zhejiang). By means of acetylation, acid hydrolysis, IR, MS, and 13C-NMR etc., five of them were identical with yononin (A) (yield 0.0069%), dioscin (C) (0.04%), gracillin (D) (0.03%), protodioscin (E) (0.5%), protogracillin (F) (0.2%), respectively. Because of low yield, saponin B was not identified.     

Growth and Production of Steroidal Sapogenins and Glycoalkaloids in Solanum jasminoides Paxt., Suspension Cultures

Fumarate reductase was highly purified from the cytosol fraction of the cells of baker’s yeast, which were anaerobically cultured, with a yield of 6% by .7 steps. The purified enzyme is homogeneous in disc-gel electrophoresis, and has a molecular weight of 58,800. Its isoelectric point is 5.3. The enzyme contains 1 molecule of non-covalently bound FAD per molecule of protein. Non-heme iron was not detected. The amino acid composition was determined. The spectra of the enzyme showed absorption peaks at 273, 380 and 456 nm with shoulders at 370, 440 and 478 nm. The fluorescence spectra showed excitation peaks at 452 and 368 nm and an emission peak at 500 nm. Double-reciprocal plots of the reaction rate against the FADH₂ and FMNH₂ concentrations curved upwards. The hill coefficient values and S_0.5 for FADH₂ and FMNH₂ were estimated to be 1.6 and 0.21 µm, and 1.5 and 0.38 µm, respectively. The Km for fumarate was 0.2 mm.     

A New Steroidal Glycoside from Ophiopogon japonicus (Thunb.) Ker-Gawl.

To study the chemical constituents from traditional Chinese herb Ophiopogon japonicus(Thunb.) Ker-Gawl., a new steroidal glycoside, named ophiopojaponin C (1), together with two known ones,was isolated by column chromatography. Spectroscopic and chemical evidence revealed the structures to be ophiopogenin 3-O-[α-L-rhamnopyranosyl(1→2)]-β-D-xylopyranosyl(1→4)-β-D-glucopyranoside (1),diosgenin 3-O-[2-O-acetyl-α-L-rhamnopyranosyl( 1 →2)] -β-D-xylopyranosyl( 1 →3)-β-D-glucopyranoside (2),and ruscogenin 1-O-[2-O-acetyl-α-L-rhamnopyranosyl(1→2)]-β-D-xylopyranosyl(1→3)-β-D-fucopyranoside(3).     

A New Steroidal Glycoside from Ophiopogon japonicus （Thunb.） Ker-Gawl.

To study the chemical constituents from traditional Chinese herb Ophiopogon japonicus （Thunb.） Ker-Gawl., a new steroidal glycoside, named ophiopojaponin C （1）, together with two known ones, was isolated by column chromatography. Spectroscopic and chemical evidence revealed the structures to be ophiopogenin 3-O-[α-L-rhamnopyranosyl（1→2）]-β-D-xylopyranosyl（1→4）-β-D-glucopyranoside （1）, diosgenin 3-O-[2-O-acetyl-α-L-rhamnopyranosyl（1→2）]-β-D-xylopyranosyl（1→3）-β-D-glucopyranoside （2）, and ruscogenin 1-O-[2-O-acetyl-α-L-rhamnopyranosyl（1→2）]-β-D-xylopyranosyl（1→3）-β-D-fucopyranoside （3）.     

中国薯蓣属植物中的甾体皂苷及甾体皂苷元

中国薯蓣属(Dioscorea L.)植物含有约21种甾体皂苷元,其中大部分种类含有3β-羟基皂苷元,少数种类含有3α-羟基皂苷元。从薯蓣属13种植物中共分离出59个甾体皂苷成分,按化学结构可将这些甾体皂苷分为4种类型。约有17种薯蓣属植物含有甾体皂苷元(主要为薯蓣皂苷元),均为根茎组(Sect.Stenophora)种类。在查阅大量资料的基础上,对各种类所含的甾体皂苷元和甾体皂苷成分及各成分的化学结构进行了归纳和综述。     

淮山微波真空干燥特性与动力学模型

探索了淮山在不同切分方式、热烫条件、装载量、真空度、转盘转速、温度、切片厚度等干燥条件下的干燥特性,并建立了干燥动力学模型。结果表明:切分方式、装载量、真空度、温度与切片厚度对淮山干燥速率的影响显著。选用6种常用的干燥模型对不同真空度下的试验数据进行非线性回归拟合,并确定了模型参数。结果发现Page模型具有较高的拟合度(R2)与较低的残差平方和,且P <0. 01,说明该模型能较准确地表达和预测淮山微波真空干燥过程的水分变化规律。     

怀山药微型块茎愈伤组织的诱导形成及高频率再生

对怀山药微型块茎愈伤组织的诱导及高频率再生进行了研究。结果表明 :(1)光下诱导铁棍山药脱分化形成愈伤组织 ,6 -BA2 mg/L NAA2 mg/L 为最佳激素组合。KT2 mg/L 2 ,4 - D2 mg/L 有利于铁棍山药愈伤组织的增殖。附加 2 mg/L NAA能缩短 4 7号山药愈伤组织的诱导时间。KT2 mg/L NAA2 m g/L 有利于 4 7号山药愈伤组织增殖 ;(2 )不同光照条件对愈伤组织的诱导和增殖影响不同。光照是缩短 4 7号山药愈伤组织诱导时间的另一因素。暗培养有利于愈伤组织的增殖 ,对 4 7号山药来说 ,暗培养下诱导率也较高 ;(3)基因型不同 ,愈伤组织类型不同 ,诱导率和不定芽分化率也有差异 ,4 7号山药高于铁棍山药 ;(4 )KT对 4 7号山药愈伤组织分化形成不定芽起主要作用 ,2 ,4 - D2 mg/L KT2 mg/L 为最佳激素组合 ;(5 )光培养有利于不定芽的分化