Chemotaxonomical investigations of theSymphytum officinale polyploid complex andS. asperum (Boraginaceae): The pyrrolizidine alkaloids

By means of thin layer chromatography in conjunction with mass spectrometry the pyrrolizidine alkaloid patterns derived fromSymphytum asperum, several cytotypes ofS. officinale agg. and the artificial hybrids of the former taxa, were compared. The obtained patterns were not essentially affected by variation in cytotype, harvesting times and -location of plants. Lycopsamine, acetyl-lycopsamine and symphytine or their isomers were generally found in theS. officinale cytotypes, echimidine and symphytine inS. asperum. The interspecific hybrids contained all alkaloids mentioned. The definite lack of echimidine in the 2 n=40 cytotype proves that it is conspecific withS. officinale and does not belong to a hybrid-swarmS. asperum × S. officinale with 2 n=48. Part I of this series of contributions.     

Galanthamine production by Leucojum aestivum L. shoot culture in a modified bubble column bioreactor with internal sections

Shoot culture of summer snowflake (Leucojum aestivum L.) was successfully cultivated in an advanced modified glass‐column bioreactor with internal sections for production of Amaryllidaceae alkaloids. The highest amounts of dry biomass (20.8 g/L) and galanthamine (1.7 mg/L) were achieved when shoots were cultured at 22°C and 18 L/(L·h) flow rate of inlet air. At these conditions, the L. aestivum shoot culture possessed mixotrophic‐type nutrition, synthesizing the highest amounts of chlorophyll (0.24 mg/g DW (dry weight) chlorophyll A and 0.13 mg/g DW chlorophyll B). The alkaloids extract of shoot biomass showed high acetylcholinesterase inhibitory activity (IC₅₀ = 4.6 mg). The gas chromatography–mass spectrometry (GC/MS) profiling of biosynthesized alkaloids revealed that galanthamine and related compounds were presented in higher extracellular proportions while lycorine and hemanthamine‐type compounds had higher intracellular proportions. The developed modified bubble‐column bioreactor with internal sections provided conditions ensuring the growth and galanthamine production by L. aestivum shoot culture.     

细叶石斛有效成分分析及其水溶性提取物的血管舒张活性

对细叶石斛(DendrobiumhancockiiRofle)茎上部、茎中部、茎下部和根中的多糖、生物碱和矿质元素含量进行了分析,并研究了其水溶性提取物对SD大鼠胸主动脉血管的舒张效应。结果表明,细叶石斛中总多糖含量较高,并含有较多的钾、钙、镁、铁、锰、锶、钛和铜等元素,与细茎石斛〔D.moniliforme(L.)Sw.〕及铁皮石斛(D.officinaleKimuraetMigo)相比,其水溶性多糖和生物碱的含量较低,而且不同部位中的含量存在差异。细叶石斛水溶性提取物强烈拮抗苯肾上腺素所致的大鼠胸主动脉血管收缩作用,对内皮完整和无内皮功能的2种样本均引起类似的浓度依赖性舒张效应,相关系数有显著意义(>r0.01),两者的IC50分别为0.309和0.404g L。     

Produits neutres et alcaloides de Myrtopsis macrocarpa,M. myrtoidea,M. novae-caledoniae et M. sellingii

Stems and leaves of Myrtopsis macrocarpa, M. myrtoidea, M. novae-caledoniae and M. sellingii yielded terpenes, sterols, coumarins, alkaloids (furoquinolines and quinolones) and amides. A new quinolone (8-methoxy flindersine) occurs in Myrtopsis macrocarpa, a new amide (N-benzoyltryptamine) in M. myrtoidea, two new coumarins (myrsellin and myrsellinol) and a new dihydrofuroquinoline (myrtopsine) in M. sellingii. Structures of the new compounds are proposed from chemical and spectroscopic evidence.     

Alkaloids,limonoids and furocoumarins from three Mexican Esenbeckia species

The chemical constituents of three Mexican Esenbeckia species have been determined. Rutaevin was the main limonoid present in the seeds of all three species, E. litoralis, E. flava and E. berlandieri. The husks, leaves, wood and bark contained a wide array of known furocoumarins and furoquinoline alkaloids. In addition, 1-hydroxy-3-methoxy-N-methylacridone was obtained from E. litoralis bark and a new natural 2-quinolone alkaloid, formulated as 3,3-diisopropyl-N-methyl-2,4-quinoldione, was obtained from E. flava wood. The structure was assigned from spectroscopic considerations and conversion to N-methylhaplofoline.     

Inhibition of platelet aggregation and thrombosis by indole alkaloids isolated from the edible insect Protaetia brevitarsis seulensis (Kolbe)

Protaetia brevitarsis seulensis (Kolbe) has been temporarily registered as a food material by the Ministry of Food and Drug Safety of Korea (MFDS). The current study aimed to discover small antithrombotic molecules from this edible insect. Five indole alkaloids, 5‐hydroxyindolin‐2‐one ( 1 ), (1R,3S)‐1‐methyl‐1,2,3,4‐tetrahydro‐β‐carboline‐3‐carboxylic acid ( 2 ), (1S,3S)‐1‐methyl‐1,2,3,4‐tetrahydro‐β‐carboline‐3‐carboxylic acid ( 3 ), (3S)‐1,2,3,4‐tetrahydro‐β‐carboline‐3‐carboxylic acid ( 4 ) and L‐tryptophan ( 5 ), were isolated from the insect. Among them, compounds 1 and 2 prolonged aPTT and PT and impaired thrombin and FXa generation on HUVEC surface. Moreover, these compounds inhibited platelet aggregation. Antithrombotic effects of compounds 1 and 2 were further confirmed in pre‐clinical models of pulmonary embolism and arterial thrombosis. Collectively, these results demonstrated that compounds 1 and 2 could be effective antithrombotic agents and serve as new scaffolds for the development of antithrombotic drug.     

HPLC-NMR/HPLC-MS analysis of the bark extract of Stauranthus perforatus

A combination of HPLC-MS and HPLC-NMR techniques has been used to analyse the cytotoxic fractions of the dichloromethane extract of bark of Stauranthus perforatus. Six furanocoumarins (byakangelicol, heraclenin, heraclenol, imperatorin, isopimpinellin and xanthotoxin) and nine quinoline alkaloids (two known compounds, veprisine and 5-hydroxy-1-methyl-2-phenyl-4-quinolone, along with seven novel compounds, stauranthine, 3',4'-dihydroxy-3',4'-dihydroveprisine, 3',4'-dihydroxy-3',4'-dihydrostauranthine, 3',6'-dihydroxy-3',6'-dihydroveprisine, 3',6'-dihydroxy-3',6'-dihydrostauranthine, 6'-hydroxy-3'-ketoveprisine and 6'-hydroxy-3'-ketostauranthine) have been identified in the fractions.     

Traits of transgenic Atropa belladonna doubly transformed with different Agrobacterium rhizogenes strains

Hairy root cultures of Atropa belladonna L. were established by infection either with Agrobacterium rhizogenes ATCC 15834 or MAFF 03-01724, and transgenic plants were obtained from both hairy root cultures. Doubly transformed roots were induced by re-infection of the leaf segments of transgenic Atropa belladonna plants (A. rhizogenes 15834) with MAFF 03-01724. Shoots and viviparous leaves were regenerated from the doubly transformed roots. The genetic transformation was determined by the opine assay (agropine, mannopine and/or mikimopine) and polymerase chain reaction. Physiological changes and tropane alkaloid biosynthesis in the hairy roots (singly and doubly transformed) were investigated. The alkaloid content in the doubly transformed root strain was intermediate as compared to the root strains which were singly transformed. On the other hand endogenous IAA levels in doubly transformed roots were significantly decreased compared to both singly transformed roots.Abbreviations BA benzyladenine - IAA indoleacetic acid - NAA naphthaleneacetic acid - PCR polymerase chain reaction - t-ZR trans-zeatin     

Structures of Sarcorucinine D and Pachyaximine A,B

In this paper, three new alkaloids, sarcorucinine D (1), and paehyaximine A, B (2, 3) were isolated from Sarcococca ruscifolia Stapf and Pachysandra axillaris Franch, respectively. The structures of sarcorucinine D (1) and pachyaximine A, B (2, 3) were elucidated to be 3β-hydroxyl-20α-dimethylamino-5α-pregnane (1); and 3β-methoxyl-20α-dimethylamino-pregne-5-ne (2); and 3β-methoxyl-16-hydroxyl-20α-dimethylaminopregne-5-ne (16-hydroxyl-pachyaxi- mine A) (3), respectively.     

Occurrence of N-cyano alkaloids in asian Strychnos species

The isolation of N-cyano-sec.-pseudostrychnine and N-cyano-sec.-pseudobrucine from the leaves of Strychnos wallichiana Steud. ex. DC. is reported. N-Cyano-sec.-pseudostrychnine and a N-cyano-sec.-pseudo-colubrine have been found among the alkaloids obtained from the stem bark of S. ignatii Berg.