Contents

Chapter 1 Definition, Typology and Occurrence of Alkaloids 1 2. Occurrence in nature 12 2.1. The Dogbane botanical family (Apocynaceae) 13 2.2. The Aster botanical family (Asteraceae) 17 2.3. The Logan botanical family (Loganiaceae) 19 2.4. The Poppy botanical family (Papaveraceae) 21 2.5. The Citrus botanical family (Rutaceae) 22 2.6. The Nightshade botanical family (Solanaceae) 25 2.7. The Coca botanical family (Erythroxylaceae) 27 2.8. The Borage botanical family (Boraginaceae) 28 2.9. The...

Regulation of stimulation

Many alkaloids are generally known to have stimulating properties, such as caffeine, cathine, theobromine and theophylline. These alkaloids are considered in many different medical applications. Caffeine is a known inhibitor of phosphodiesterase. Caffeine has an effect on calcium-mediated signalling namely it causes an increase of cAMP activity. Caffeine also has a competitive effect on the central adenosine receptor and is thought to increase analgesic activity. It is also known to be somewhat...

Aberrations in cells

Pyrrolizidine alkaloids are toxic to foreign organisms (Figure 89). This problem was largely studied in the Serious livestock poisoning episodes are mentioned in literature from the effects of the pyrrolizidine alkaloid of the Senecio genus especially Senecio riddellii, Senecio douglasii and Senecio jacobaea411. The toxicity of pyrrolizidine alkaloids to livestock was considered coincidental. Johnson and Molyneux501 and Johnson et al.502 have stated that experimental feedings of pyrrolizidine...

Alkaloids in biology

For many years, the nature of alkaloids in biology was a mystery. It has been difficult to understand the function of these compounds in plant metabolism. There are many explanations for why plants, animals and micro-organisms produce alkaloids. Nowadays, when genomes, DNA and genes serve as the basis for biological explanations, this issue is of great importance and still open for discussion and for deep scientific analysis. Despite the advanced research in the field, a final comprehensive...

Alkaloids in plant protection

Many investigations have been carried out with the purpose of investigating the possibility of using alkaloids in plant protection617'618'619'620'621. Organic farming requires new possibilities to protect plants without strong synthetic pesticides. Natural botanicals and natural compounds extracted from plants are considered as possibilities. Alkaloids are considered useful for this purpose. Quinolizidine alkaloids, pure or in mixtures of plant extract, can be used to protect plants against...

Capillary zone electrophoresis

Capillary electrophoresis is suitable for use to separate a wide spectrum of both large and small biological molecules. This method was used for analysis of opium alkaloids such as thebanine, codeine, morphine, papaverine and narcotine. 2.9.4. Choice of method and confidence There exists a long list of different methods of quinolizidine alkaloid analysis (Table 21). These methods are of a chemical and biological nature. The development of methods of alkaloid analysis has been a long and...

Causers of locoism

Indolizidine alkaloids are also known as active biotoxins. Swansonine is especially cited in literature as a cause of locoism. This is a neurological lesion, especially in horses, cattle and sheep508. According to Elbein and Molyneux509 swansonine is toxic due to the imbibition of a-mannosidase, an enzyme needed for proper functioning of mammalian cells. It is also known that swansonine inhibits several hydrolases. In addition, Astragalus lentiginous produces lentiginosine, which is an alkaloid...

Definition Typology and Occurrence of Alkaloids

Abstract Alkaloids are a group of molecules with a relatively large occurrence in nature around the Globe. They are very diverse chemicals and biomolecules, but they are all secondary compounds and they are derived from amino acids or from the transamination process. Alkaloids are classified according to the amino acids that provide their nitrogen atom and part of their skeleton. Similar alkaloids can have quite different biosynthetic pathways and different bioimpacts. Alkaloids are derived...

Discussion of case study results

The QAs occur in all the legume species included in this study but not in all individuals. This suggests additional evidence of the evolutionary role of secondary compounds, which are important for plant survival and reproductive fitness7 325. Thus, the mechanism for production of QAs has hereditary characteristics740'746'747. In some respects, the occurrence of alkaloids in legumes was disputed by previous literature. However, there was no dispute over whether QAs occur in Fabaceae. Bohlmann...

From stimulators to inhibitors and destroyers of growth

Waller and Nowacki16 distinguished the role of alkaloids in plants as growth stimulators and inhibitors and also as protective agents and reservoirs of nitrogen. Some alkaloids are known neurotransmitters in animals and can also be considered part of the signalling system. This system is constructed as a part of cell and metabolic operations controlled by functional mechanisms of biological membranes, channels, receptors and enzymes. It is known that some alkaloids, for example purine and...

Haemoglobinization of leukaemia cells

The biological activity of alkaloids can be demonstrated by fagaronine (Figure 82), an alkaloid isolated from Fagara zanthoxyloides Lam. (Rutaceae). This alkaloid alone has been tested by many research groups as biological agent of the haemoglobinization of human leukaemic cells372'373'374'375'376. One of the characteristics of leukaemic cells is escaping the normal regulatory pathway controlling cell proliferation and differentiation. As early as in 1972, Messmer et al.372 reported on...

Life regulation through the high and low cytotoxicity

Alkaloids from the plant family Amaryllidaceae are known to have a wide range of biological activities. They have analgesic, antiviral, anti-malarial, antineoplastic properties and display effects on the CNS. Elgorashi et al.354 have studied 25 Amaryllidaceae alkaloids for possible inhibitory activity of their acetylcholinesterase enzyme (AChE). This enzyme is biologically very important. According to the cholinergic hypothesis Alzheimer's disease symptoms result from AChE activity, which...

Lysinederived alkaloids

Lupinine From Lysine

L-lysine furnishes alkaloids with at least four different nuclei. It is a protein amino acid, one of the most important alkaloid precursors. L-lysine-derived alkaloids have a basic skeleton with C5N (the piperidine nucleus) and C5N +____ (indolizidine, quinolizidine and pyridon nuclei). 2.6.1. Pelletierine, lobelanine and piperine synthesis pathway Alkaloids with the piperidine nucleus, such as pelletierine (Punica grana-tum), lobelanine (Lobelia inflata) and piperine (Piper nigrum), have a...

Material and methods

This case study was carried out in the Research and Teaching Laboratory of Applied Botany under the auspices of the Department of Biology of the University of Joensuu, Finland (N 62 36' E 29 40') from 1999 to 2003 as a part of the larger project, Quinolizidine alkaloids in arctic and sub-arctic flora. This large project explores the broader problem of QAs occurring in plants growing in northern ecosystems. This case study presents and discusses the research results from the first part of this...

Methods of alkaloid analysis

These analytical dilemmas interfere with the methods of alkaloid analysis. Each group of alkaloids has its own methods of extraction, isolation and crystallization, as well as detection in structure, molecule and dynamicity. Not all these stages are still possible in the majority of alkaloids. In recent years, many techniques have been used in alkaloid detection. There are atomic and molecular electronic spectroscopy, vibration spectroscopy and electron and nuclear spin orientation in magnetic...

Methods of analysis

This presentation of basic alkaloid synthesis pathways clearly reveals the diversity and complicity of this process in nature. Moreover, the large number of different pathways and synthesis routes proves the status of alkaloids as a phenomenon of the metabolic activity of organisms. Here, we have seen only the basic pathways and routes. In reality, each alkaloid has its own synthesis route. It is possible to find or to place it on one of the basic pathways. Certainly, experimental data is...

Quinolizidine alkaloids

The third structural group of alkaloids, from the same a, are quinolizidine alkaloids (QAs). It is a large group of compounds with very different The structural development of quinolizidine alkaloids is presented in Figure 54. The a (l-lysine) provides the basic components of the quinolizidine nucleus and skeleton. The is cadaverine and is synthesized in the same way as piperidine alkaloids (by the activity of PLP). The transformation from to also occurs through the activity of diamine oxidase...

Regulation of microtubules of the spindle apparatus

Alkaloids such as vinblastine and vincristine are known to bind to the microtubules of the spindle apparatus. They are active agents that influence DNA synthesis and amino acid metabolism. They are also known to reduce mitosis at metaphase. Vinblastine and vincristine also have some immunosuppressive activity. There are many applications of these alkaloids. They have been used in the treatment of Hodgkin's disease, cancers and blood disorders. Vincristine is a basis for the development of...

Regulation of Na ions and channels

As previously mentioned in this book, alkaloid biological activity is rather diverse, and alkaloids, therefore, have biological significance as histological regulators of metabolism. This significance is pertinent to the development of the applications. One such important role of some alkaloids is their influence on Na+ channels and interaction with receptors. Aconitine, ajmaline, sanguinarine (Figure 93) and sparteine have clinical uses in this respect. Aconitine causes an influx of Na+ ions...

Root cultures

In vitro production of alkaloids is possible also with the use of another in vitro technique organ culture. Root cultures are the most common concerning alkaloids, as this part of plants is of great importance for alkaloid synthesis. Root cultures that produce alkaloids have been studied as far back as the 1950s658, but this subject did not come under wide scrutiny until the Root cultures with the ability to produce alkaloids have importance nowadays in biotechnology and genetic...

Selective effectors of death

One of the most known toxic alkaloid is strychnine. Vanderkop467 and Sterner et al.468 are examples of those who have studied its toxicity, although it is practically rather evident. This alkaloid has been used as a strong rodenticide225. It is also known for being dangerous to humans. One general characteristic of strychnine is its chemical stability. This is some kind of exception in the alkaloids, which are generally flexible heterogeneous compounds. In cases of poisoning this alkaloid can...

Sesquiterpene pyridine alkaloids

Compounds belonging to this group of alkaloids are sourced from the Celas-traceae and Hippocrateaceae families and contain the sesquiterpene nucleus. More than 220 alkaloids are known in this group58. Sesquiterpene pyridine Claisen reaction neophilic addition dehydration and enolization Claisen reaction neophilic addition dehydration and enolization Figure 60. Structural development of acridone alkaloids. Figure 60. Structural development of acridone alkaloids. alkaloids can be divided into...

Skeleton diversity

The skeleton nucleus of the alkaloid is the main criterion for alkaloid precursor determination. Many skeletons are produced in the process of alkaloid synthesis. Figure 24 illustrates some nuclei and skeletons supplied in the synthesis. Alkaloid Indole alkaloids Quinoline alkaloids Ergot alkalo Indolizine alkaloids Piperidine alkaloids Indolizine alkaloids Piperidine alkaloids Simple L-Tyrosine alkaloids Quinazoline ADP NAD L -Tryptophan ATP QH NADH2 -- - Tryptophan yAnthranilic C o Tyucinee...

Taxonomic Index

Amaryllidaceae S6, 51, 52, 62, 15C, 151 Aspergillus terreus 43, 56 Aspergilus niger 156 Aspidosperma megalocarpon 18, 38 Aster 17, 18 Asteraceae 17, 34, 39, 103 Astragalus 30, 216, 217, 225, 227 Astragalus alpinus 220, 221, 222, 225, 228 Astragalus arenarius 220, 221, 222, 225, 227, 228 Astragalus cicer 220, 221, 222, 225, 227, 228 Astragalus frigidus 220, 221, 222, 225, 227, 228 Astragalus glycyphyllos 220, 221, 222, 225, 227, 228 Astragalus lentiginous 168 Atropa 25, 26 Atropa belladonna 25,...

The Berberry botanical family Berberidaceae

L-tyrosine-derived alkaloids occur also in the Berberry botanical family (Berberidaceae Torr., Gray, Juss.) (Table 12). Berberine is produced particularly by the Berberry genus (Berberis L.) and the Mahonia genus (Mahonia Nutt.). These alkaloids are found in such species as the common berberry (Berberis vulgaris L.), native to Euroasia the Japanese berberry (Berberis thunbergii DC.), native to Asia and the Chita (Berberis aristat DC.) in the Himalayas. It is also present in Holly (Mahonia...

The Borage botanical family Boraginaceae

Forget-me-not) family (Boraginaceae Lindl.) contains L-ornithine (Figure 11 and 15) derived alkaloids, such as indicine-N-oxide in the heliotrope (Heliotropium indicum) and southern hound's tongue (Cynoglosum creticum) species (Table 8). Farsam et al.46 reported on new alkaloids from Table 8 General botanical characteristics of the Borage family312,313,316 Botanical Forms and Parts Characteristics Rarely shrubs or trees Lianas (rarely) Regular Calyx 5-parted Regular...

The Coca botanical family Erythroxylaceae

Alkaloids also occur in many other plant families. It is relevant to mention the Coca plant family (Erythroxylaceae L.), distributed in the tropics and endemic to South America, especially in the regions of Peru and Bolivia, where the coca bush (Erythroxylum coca) has been known for at least 5000 years109. Typical characteristics of this family are elliptic, light green leaves (4-7 x 3-4 cm), small, white flowers and small, reddish-orange drupes318. Nowadays, it is distributed in the Andean...

The Coffee botanical family Rubiaceae

Madder) botanical family (Rubiaceae Juss.) (Table 15) consists of more than 400 genera and over 6000 species. It grows in the tropics and the sub-tropics. Plants belonging to this family include trees, bushes and liane. The Coffee plant family contains two major purines of adenine- guanine-derived alkaloids, the so-called purine alkaloids. Purine is a nitrogenous base of nucleotide, which consists of just purine and pentose sugar (D-ribose or 2 deoxy-D-ribose). Typical purine...

The effects of stress and endogenous security mechanisms

In biology today, the basic question concerning alkaloids is connected with the relation between their internal and external roles. It appears that the external role is only secondary, and the endogenous use of alkaloids as genetically coded is the primary function. H ft et al.344 have studied the sources of alkaloid formation and changes in Tabernaemontana pachysiphon plants. In this research the endogenous factors were leaf age, plant age, leaf position in the crown and teratological leaf...

The intermedia

The intermedia is a compound formed from the precursor in each alkaloid synthesis pathway. In the case of non-protein aminoacids as precursors of alkaloids, the intermedia is generally a biogenic amine (e.g., putrescine in hygrine and other pyrrolidine and tropane alkaloid pathway (Figure 33), dihydronicotinic acid in the nicotine pathway (Figure 47) or nicotinamide in the ricinine pathway (Figure 48) and the amide formation compound in peganine or the dictamnine pathway). Generally speaking,...

The Lily botanical family Liliaceae

The Lily botanical family (Liliaceae Adans., Juss.) (Table 14) is spread worldwide and contains more than 200 genera and around 3500 species. Some genera of this family produce L-tyrosine-derived alkaloids. The genus Kreysigia yields autumnaline, floramultine and kreysigine. The genus Colchicum (Colchicum L.) produces colchicine. Stereoidal alkaloids in this family are found in the Hellebore genus (Veratrum Bernch.). Jervine, cyclopamine (Figure 18), cycloposine, protoveratrine A and...

The Poppy botanical family Papaveraceae

The Poppy botanical family (Papaveraceae) contains L-tyrosine (Figure 12) derived alkaloids such as morphine, codeine, thebanine, papaverine, narcotine, narceine, isoboldine and salsolinol. The Poppy family is relatively large, comprising 26 genera and about 250 species. The family is distributed in the sub-tropical and temperate regions of the northern hemisphere (Table 5). The opium poppy (Papaver somniferum L.) is a known source of opium from its latex. The Poppy family alkaloids have strong...

True alkaloids

True alkaloids derive from amino acid and they share a heterocyclic ring with nitrogen. These alkaloids are highly reactive substances with biological activity even in low doses. All true alkaloids have a bitter taste and appear as a white solid, with the exception of nicotine which has a brown liquid. True alkaloids form water-soluble salts. Moreover, most of them are well-defined crystalline substances which unite with acids to form salts. True alkaloids may occur in plants (1) in the free...

The Nightshade botanical family Solanaceae

The Nightshade plant family (Solanaceae Pers.), containing 90 genera and more than 2000 species distributed in all continents, particularly is abundant in alkaloids (Table 7). The plant species belonging to this family grow especially in the tropics and sub-tropics. However, the majority of the species occur in Central and South America. The L-ornithine (Figures 11 and 15) derived alkaloids occur in many species of this family. Hyoscyamine and hyoscine and cuscohygrine are in the genus...

Alkaloids as secondary metabolism molecules

The precursors of true alkaloids and protoalkaloids are aminoacids (both their precursors and postcursors), while transamination reactions precede pseudoalka-loids (Tables 1 and 10). It is not difficult to see that from all aminoacids only a small part is known as alkaloid precursors (Table 19). Both true and proto alkaloids are synthesized mainly from the aromatic amino acids, phenylalanine, tyrosine (isoquinoline alkaloids) and tryptophan (indole alkaloids). Lysine is the Table 19 Amino acids...

Cell cultures

Alkaloids can be produced by using cell culture techniques in the same or a similar way as with other molecules624. Alkaloids such as ajmalicine, serpentine (C. roseus) and berberine (Coptis japonica) can produce remarkable quantities of alkaloids in in vitro cultures625 626. Generally, cell cultures produce species-specific alkaloids. In some cases cell cultures can produce more alkaloids than the whole plant, in relation to dry weight. This occurs, for example, in the cases of nicotine,...

List of Figures

1 Contemporary scheme of morphine. 2 2 Some alkaloids isolated by pharmaceutists Pierre Joseph Pelletier and Joseph Beiname Caventou during 1817-1821. 3 3 Schemes of taxol, vinblastine, vincristine and vincamine 5 4 An example of a true alkaloid 11 5 An example of protoalkaloids 11 6 An example of a pseudoalkaloid 12 7 The raw extraction of quinolizidine alkaloids 13 8 L-tryptophan with its aromatic side chain 15 9 The devil's-pepper genus, Rauwolfia serpentina 15 10 L-phenylalanine is a...

Mushroom

Alkaloids occur in many other botanical families. Moreover, there are alkaloids derived from L-tryptophan which occur in mushrooms genera Psilocybe mushrooms (Psilocybe), Conocybe mushrooms (Conocybe), Haymaker's mushrooms (Panaeolus) and Stoparia mushrooms (Stoparia). Serotonin, psilocin and psilocybin are basic alkaloids derived from these mushrooms (Figure 19). They are powerful psychoactive and neurotransmitter compounds. Recreational use of hallucinogenic mushrooms has been reported in...

Nicotinic acidderived alkaloids

Alkaloids derived from nicotinic acid contain a pyridine nucleus. Nicotinic acid itself is synthesized from L-tryptophan via N-formylkynurenine, L-kynurenine, 3-hydroxykynurenine, 3-hydroxyanthranilic acid and quinolinic acid. The pyridine nucleus is passed to alkaloids via dihydronicotinic acid, moving from dihydropyridine to nicotine and nornicotine (Figure 47). Dihydronicotinic acid is synthesized by the enzymatic activity of NADP and subsequently becomes 1,2-dihydropyridine by a reduction...

Applications

Abstract Alkaloid applications can be found in different areas. Some alkaloids are still used in modern medicine today as natural or modified compounds. Their use is connected to the regulation of Na+ ions and channels, mescaric, cholinergic receptor, acetylcholine esterase, opioid and opiate receptors, glycine and other receptors, as well as the regulation of micro-tubules of the spindle apparatus. Moreover, alkaloids are used in the regulation of microbial and schizonticide activity and as...

Influence on DNA

The phenethylisoquinoline alkaloids present in some members of the Lily family (Liliaceae) are known to be toxic. Wang and Wang457 have researched the activity of veratridine on rats. This alkaloid causes persistent opening of the voltage-gate Na+ channel and reduces its single-channel conductance by 75 . However, its toxicity is concentration dependent. The toxicity of iso-quinoline alkaloid berberine is low in concentrations 0.05 for living plant cells464. In these concentrations berberine...

Alkaloids in food

Alkaloidal plants used as food are small in number. The reason for this is the bioactivity and traditional use of alkaloids in medicines and drugs. Moreover, food is checked and controlled with the purposes of keeping alkaloid-contaminated food off the market. However, cases where pyrrolizidine alkaloids were found in the honey produced by bees that had foraged on the flowers of Echium and Senecio species are documented475'495'591. In these relatively old studies, bees had been feeding only on...

Regulation of schizonticide activity

Quinidine and quinine have schizonticide activity due to the inhibition of nucleic acid synthesis through DNA intercalation. This activity is also based on carbohydrate metabolism. The action of both of these alkaloids is a result of their binding to sarcoplasmic reticular vesicles and the resulting reduced uptake of Ca2+. These alkaloids are also active on Na+ and K+-ATPase, both in an encouraging or inhibiting sense. Both alkaloids therefore have been developed as strong anti-malarial...

Alkaloids - Secrets Of Life

This book is intended to be a presentation of alkaloids from chemical, biological and ecological points of view. It is a text for chemists, biologists and ecologists alike. However, the intended audience of this work is not limited to scientists, teachers and other present and future specialists. In fact, I wrote this book because I felt the need for it as a university educator and as a scientific enthusiast on the subject. My purpose was to compose a beneficial text for an academic and...

Alkaloids as biological fertilizers

Alkaloids from many plants are considered to be used as biological fertilizers in ecological cultivation. This is very important especially in cases when more attention is given to these plants, which play not only a role in production but also in the cyclical maintenance of a field, garden or forest ecosystems614'615'616. Plants containing alkaloids, for example lupines, have the ability to establish complexes with the soil and with the rhizosphere. The excretion of many chemicals from roots...

Antiparasitic activity

A parasite is an organism living in or on, and metabolically depending on, another organism. Endoparasites live inside an organism, and ectoparasites live on the surface of the host. Parasites can be carnivorous if living with animals or herbivorous if living with plants. Analyses of parasite host suggest strong evidence of anti-carnivorous anti-herbivorous action of alkaloids. A good example is with protozoan parasites Plasmodium spp. injected into humans by mosquitoes of the genus Anopheles....

Biogenesis of alkaloids

The synthesis and structural analysis of alkaloids leads to the following basic questions why are alkaloids synthesized in an organism and on which mechanism is alkaloid formation and degradation dependent in the life cycle It is known that alkaloids have a genetic nature59 and that alkaloid content is diverse inside and between the species16. In nature the same species of plants may have both high and low alkaloid content120121. Natural hybridization has been successfully used in plant...

The Legume botanical family Fabaceae

Calabar Bean

Alkaloids derived from L-ornithine, L-lysine, and L-trypthophan occur in the Legume plant family Fabaceae Juss. Table 9 . This plant family is the third largest botanical family, with 650 genera and 18000 species in the humid tropics, sub-tropics, temperate and sub-arctic zones around the Globe118. L-ornithine-derived alkaloids such as senecionine are present in the genus Crota Crotalaria L. . The most typical alkaloids for this botanical family are L-lysine Figure 16 derived alkaloids, such as...

Pseudoalkaloids

Pseudoalkaloids are compounds, the basic carbon skeletons of which are not derived from amino acids31. In reality, pseudoalkaloids are connected with amino Figure 6. An example of a pseudoalkaloid. Acetate-derived alkaloid pinidine is extracted from the Pinus species, for example, from Pinus penderosa. Photo T. Aniszewski . Pinidine has antimicrobial activity. Figure 6. An example of a pseudoalkaloid. Acetate-derived alkaloid pinidine is extracted from the Pinus species, for example, from Pinus...

Antimicrobial properties

It is generally recognized that alkaloids have strong antimicrobial, antibacterial and antifungal biological Moreover, some studies have evidenced anti-parasitic activity in this group of compounds392 393. Caron et al.329 have investigated 34 quasi-dimeric indole alkaloids for antimicrobial activity using 8 different test micro-organisms. It was found that all of the studied alkaloids showed activity against Staphylococcus aureus and Bacillus subtilis, which are Gram-positive bacteria. Caron et...

Animals

Alkaloids are also found in the animal kingdom, especially in millipedes, salamanders, toads, frogs, fish and mammals. They occur particularly in the genera Saxidomus, Salamandra, Phyllobates, Dendrobates, Castor and Moschus. Moreover, alkaloid molecules are found in such genera as Solenopsis, Odon-tomachus, Glomeris and Polyzonium. Many alkaloids have been recently isolated from marine environment, especially from the sponges197. The discovery of ptilomycalin A from the sponges Ptilocaulis...

Eduline Circulatory System

Structural development of phenyl and phenylpropyl alkaloids. alkaloids e.g., eserine and ergot alkaloids e.g., ergotamine . Indole alkaloids form a very important group from the perspective of their application. The a for structural development of serotonin simple indole alkaloid is L-tryptophan, and the ft is 5-hydroxy-L-tryptophan Figure 64 . Serotonin is a monoamine. It is a bioactive alkaloid known as a neurotransmitter. It has been found in the cardiovascular system, in blood...

Alkaloid Index

25 2-hydroxy-4-methoxy-3- 3' -methyl-2'- butenyl -quinoline 24 2-methoxyl-3- 3-indolyl -propionic acid 31, 39 2-O,N-dimethylliriodendronine 35, 45 3 R -benzoyloxy-2 R -methyl-6 R - 11'-oxododecyl -piperidine 152 3'-hydroxy-N-methylcoclaurine 176 3-hydroxysarpagine 16 3-methoxy-tabernaelegantine C 16 3-R S-hydroxy-conodurine 16 16 3 8,13a-dihydroxylupanine 31 3 -hydroxylupanine 31 4-hydroxystachydrine 10, 11, 34 4'-O-methylnorbelladine 78, 79 4 -hydroxy-2-oxosparteine 101 4 -tigloyloxylupanine...

Tryptophanderived alkaloids

Diagram Alkaloids

Alkaloids derived from L-tryptophan hold the indole nucleus in a ring system. The ring system originates in the shikimate secondary compounds building block and the anthranilic acid pathway. It is known that the shikimate block, in general, and anthranilic acid, in particular, are precursors to many indole alkaloids. However, there are many rearrangement reactions which can convert the indole ring system into a quinoline ring. In this pathway, L-tryptophan is enzymatically transferred to...

The Ecological Role of Alkaloids

Abstract Alkaloids are a special group of secondary compounds and are part of an organism's adaptation mechanism to its living environment. They are not toxic when stored, but become toxic as a result of cell pH change. The defensive function of alkaloids is only secondary, and connected to internal immune and regulation processes. Animal responses to alkaloids are very diverse. Some animals can tolerate alkaloids relatively well, while others are harmed or even poisoned by them. Animal...

The Dogbane botanical family Apocynaceae

Some plant families are especially rich in alkaloids. The Dogbane botanical family Apocynaceae Lindl., Juss. is a good example Table 2 . This family is distributed worldwide, especially in tropical and sub-tropical areas. The Dogbane family is a large botanical taxa containing at least 150 genera and 1700 species. Alkaloids are especially abundant in the following Table 2 General botanical characteristics of the Dogbane family Opposite or verticillate with reduced stipules Pinnateveined...

Protoalkaloids

Protoalkaloids are compounds, in which the N atom derived from an amino acid is not a part of the heterocyclic31. Such kinds of alkaloid include compounds derived from L-tyrosine and L-tryptophan see Table 1 . Protoalkaloids are those Definition, Typology and Occurrence of Alkaloids Table 1 Main types of alkaloids and their chemical groups Cocaine Hyoscyamine Scopolamine hyoscine lycopsamine Acetyl-intermedine Europine Homospermidine Ilamine Anaferine Lobelanine Lobeline N -methyl pelletierine...