Fungus Penicillium citrinum, isolated from permafrost sediments, as a producer of ergot alkaloids and new quinoline alkaloids quinocitrinines

Quinocitrinines and ergot alkaloids are synthesized by the strain Penicillium citrinum VKM FW-800 as the culture grows. The major part of these secondary metabolites are secreted into the medium. In the phase of growth deceleration, these metabolites were partly absorbed by the producer cells. Zinc ions stimulated both the primary and secondary metabolic processes. Addition of this microelement into the culture medium stimulated biomass accumulation and the synthesis of clavine alkaloids and quinocitrinines.     

The influence of medium composition on alkaloid biosynthesis by <Emphasis Type="Italic">Penicillium citrinum</Emphasis>

The fungus P. citrinum produces secondary metabolites, clavinet ergot alkaloids (EA), and quinoline alkaloids (quinocitrinines, QA) in medium with various carbon and nitrogen sources and in the presence of iron, copper, and zinc additives. Mannitol and sucrose are most favorable for EA biosynthesis and mannitol is most favorable for QA. Maximum alkaloid production is observed on urea. Iron and copper additives in the medium containing zinc ions stimulated fungal growth but inhibited alkaloid biosynthesis. The production of these secondary metabolites does not depend on the physiological state of culture, probably due to the constitutive nature of the enzymes involved in biosynthesis of these substances.     

Consoramides A–C,New Zwitterionic Alkaloids from the Fungus Irpex consors

In our ongoing search for new secondary metabolites from fungi, a basidiomycete fungus Irpex consors was selected for mycochemical investigation, and three new zwitterionic alkaloids (1-3) and five known compounds (4-8) were isolated from the culture broth (16 l) of I. consors. The culture filtrate was fractionated by a series of column chromatography including Diaion HP-20, silica gel, and Sephadex LH-20, Sep-Pak C₁₈ cartridge, medium pressure liquid chromatography (MPLC), and high pressure liquid chromatography (HPLC) to yield eight compounds (1-8). The structures of the isolated compounds were elucidated by the interpretation of nuclear magnetic resonance (NMR) spectra and high-resolution mass spectrometry (HR-MS). Their antioxidant and antibacterial activities were examined. The zwitterionic structures of three new sesquiterpene alkaloids (1-3) were determined together with five known compounds identified as stereumamide E (4), stereumamide G (5), stereumamide H (6), stereumamide D (7), and sterostrein H (8). This is the first report of the zwitterionic alkaloids in the culture broth of I. consors. Three new zwitterionic alkaloids were named as consoramides A–C (1-3).     

Role of Glycols and Tweens in the Production of Ergot Alkaloids by Claviceps paspali

Several glycols and Tweens markedly stimulated the production of ergot alkaloids in submerged cultures of Claviceps paspali. The role of these compounds was investigated in shake flasks and bench-scale fermentors. 2,3-Butanediol was not utilized by the fungus, and 1,2-propanediol-1-(14)C was not incorporated into the alkaloids. Glycols and Tweens lowered the surface tension of the basal medium and promoted the utilization of metabolites. In the presence of glycols and Tweens, an increased uptake of labeled sorbitol and succinic acid took place, whereas the specific radioactivity of the alkaloids was not affected. These results indicated that glycols and Tweens are not involved directly in the biosynthetic process; they apparently acted as surface-active agents, facilitating transport of metabolites into the cells.     

The influence of medium composition on alkaloid biosynthesis by Penicillium citrinum

The fungus P. citrinum produces secondary metabolites, clavine ergot alkaloids (EA), and quinoline alkaloids quinocitrinines (QA) in medium with various carbon and nitrogen sources and in the presence of iron, copper, and zinc additives. Mannitol and sucrose are most favorable for EA biosynthesis and mannitol is most favorable for QA. Maximum alkaloid production is observed on urea. Iron and copper additives in the medium containing zinc ions stimulated fungal growth but inhibited alkaloid biosynthesis. The production of these secondary metabolites does not depend on the physiological state of culture, probably due to the constitutive nature of the enzymes involved in biosynthesis of these substances.     

Pyrrolic Metabolites from Non-toxic Pyrrolizidine Alkaloids

THERE is evidence that some or all of the cytotoxic effects of unsaturated pyrrolizidine alkaloids are, in some animals, caused by pyrrolic metabolites formed by enzymatic dehydro-genation of the alkaloids in the liver^1,2. These metabolites are dihydropyrrolizine alcohols like I in Fig. 1 or their esters II; one such alcohol has been identified³. Compared with the parent alkaloids these metabolites are highly reactive alkylating agents, capable of reacting chemically with tissue constituents^1,2,4.     

Penicillium aurantiogriseum Dierckx 1901: Producer of Diketopiperazine Alkaloids (Roquefortine and 3,12-Dihydroroquefortine), Isolated from Permafrost

Secondary metabolites of three strains of Penicillium aurantiogriseumisolated from permafrost sediments were identified. It was found that these fungi synthesized the diketopiperazine alkaloids roquefortine and 3,12-dihydroroquefortine. The strain VKM FW-766 synthesized alkaloids in the course of certain growth-related processes. When the strain was grown on a mineral medium, the time courses of the roquefortine and 3,12-dihydroroquefortine concentrations were characterized by biphasic curves.     

Alkaloids of the rutaceae: their distribution and systematic significance

The biosynthesis of the alkaloids of the Rutaceae and its relevance to their systematic value is discussed. The alkaloids are divided into groups of potential systematic significance and their distribution reviewed and analysed with respect to presently accepted taxonomic classifications for the family. It is shown that, from the alkaloid data available, Engler's classification of the major sub-families Rutoideae and Toddalioideae is untenable. An hypothesis for the phylogeny of the Rutales, based on the distribution of alkaloids and other secondary metabolites, is proposed.     

石蒜属植物生物碱成分研究进展

石蒜属为东亚特有属。该属植物富含生物碱,且此类次生代谢产物具有细胞毒、抗疟疾、抗病毒以及对乙酰胆碱酯酶的抑制作用等活性。本文概述了该属中生物碱类成分的化学结构、药理活性及其生源途径。     

Adaptation of Peganum harmala Callus to Alkaloid Production

Peganum harmala callus culture growing on a fully defined mediumcontaining the auxin 2,4-D was found to form roots and secondarymetabolites when the auxin content of the medium was reduced.The secondary metabolites included alkaloids, lignin, and ared pigment. The interrelationships between these phenomenaare discussed. Alkaloids appeared in the rootlets and the dynamicsof their production were followed. Suitable sources of N, Fe,C, and energy were essential for alkaloid synthesis; other nutrientswere needed for its maximal expression. Phosphate-free mediastimulated secondary metabolite formation while limiting growthand morphogenesis. Light raised the content of the dihydro-ß-carbolinealkaloids relative to the fully aromatic derivatives but didnot alter the total accumulation of alkaloids.     

In situ extraction strategy affects benzophenanthridine alkaloid production fluxes in suspension cultures of Eschscholtzia californica

The effect of contact between cells and extractive phase on secondary metabolite production was investigated in two-phase suspension cultures of Eschscholtzia californica. A system was designed to extract benzophenanthridine alkaloids from the cell culture, without contact between XAD-7 resins and the cells: only medium was recirculated through a column packed with the extractive phase. This strategy was compared to the classic method of addition of resins directly into the cell suspension. Removal of the product directly from the medium enabled important increases in production of alkaloids, namely a 20-fold increase in sanguinarine production and a 10-fold increase in chelerythrine, with high recovery in the resin. The recirculation strategy greatly simplified the production process since the resins are easily recovered from the cell culture and enable harvest of product without termination of culture. However, due to limited flow rate, the recirculation strategy was slightly less effective than direct addition of resins into the cell suspension. In addition to enabling increased production, removal of secondary metabolites from the medium changed metabolic flux distribution, testifying to a complex control mechanism of production.     

The Fungus Penicillium citrinum Thom 1910 VKM FW-800 Isolated from Ancient Permafrost Sediments As a Producer of the Ergot Alkaloids Agroclavine-1 and Epoxyagroclavine-1

The study of the secondary metabolites of the relict strain Penicillium citrinum VKM FW-800 isolated from ancient Arctic permafrost sediments showed that this fungus produces agroclavine-1 and epoxyagroclavine-1, which are rare ergot alkaloids with the 5R,10S configuration of the tetracyclic ergoline ring system. The production of the alkaloids by the fungus showed a biphasic behavior, being intense in the phase of active growth and slowing down in the adaptive lag phase and in the stationary growth phase. The addition of zinc ions to the incubation medium led to a fivefold increase in the yield of the alkaloids. The alkaloid-producing Penicillium fungi isolated from different regions exhibited the same tendencies of growth and alkaloid production.     

Secondary metabolites in taxonomy of the <Emphasis Type="Italic">Penicillium</Emphasis> fungi

A correlation was established between species specificity and synthesis of specific secondary metabolites by the Penicillium fungi. Strains of the subgenus Aspergilloides usually synthesize metabolites of polyketide nature. Most strains of the subgenus Furcatum produce clavine ergot alkaloids and metabolites of diketopiperazine nature. The only clavine ergot alkaloids and diketopiperazine alkaloids produced by strains of the subgenus Biverticillium are rugulovasines and rugulosuvines, respectively. Species designations of the strains of the subgenus Penicillium isolated from permafrost soil, the Mir orbital complex, and sites undergoing anthropogenic load were refined based on the marker secondary metabolites. Changes in the taxonomic position of some strains in the genus Penicillium are suggested.     

Occurrence of Indole Alkaloids among Secondary Metabolites of Soil Aspergillus Spp.

The occurrence of indole alkaloids among secondary fungal metabolites was studied in species of the genus Aspergillus, isolated from soils that were sampled in various regions of Russia (a total of 102 isolates of the species A. niger, A. phoenicis, A. fumigatus, A. flavus, A. versicolor, A. ustus, A. clavatus, and A. ochraceus). Clavine alkaloids were represented by fumigaclavine B, which was formed by A. fumigatus. -Cyclopiazonic acid was formed by isolates of A. fumigatus, A. flavus, A. versicolor, A. phoenicis, and A. clavatus. The occurrence of indole-containing diketopiperazine alkaloids was documented for isolates of A. flavus, A. fumigatus, A. clavatus, and A. ochraceus. No indole-containing metabolites were found among the metabolites of A. ustus or A. niger.     

The Effect of Amino Acids as Components of Nutrient Medium on the Accumulation of Protoberberine Alkaloids in the Cell Culture of <Emphasis Type="Italic">Thalictrum minus</Emphasis>

We studied the effects of amino acids on the biosynthesis of protoberberine alkaloids. When 5 mM tyrosine was added to the nutrient medium, the content of alkaloids was reduced by 23% and dry weight was only 77% of the control. On the medium with 1 mM L-tryptophan, the content of alkaloids was somewhat increased (by 20%). Other amino acids (sulfur-containing L-cysteine and L-methionine, and also L-proline and L-arginine) did not affect substantially the content of alkaloids. The addition of 1 and 5 mM L-phenylalanine, which is not a primary precursor to alkaloids, induced the accumulation of alkaloids by the 17th day of the growth cycle by 40 and 140%, respectively, as compared to control treatment. The comparison of various phenylalanine concentrations showed that 7 mM phenylalanine added on the 7– 8th day induced the highest accumulation of alkaloids in the culture medium (above 1 g/l). The content of alkaloids and soluble phenolic compounds increased threefold in both the medium and cells. None of the amino acid tested enhanced biomass accumulation.__________Translated from Fiziologiya Rastenii, Vol. 52, No. 3, 2005, pp. 438–442.Original Russian Text Copyright © 2005 by Urmantseva, Gaevskaya, Karyagina, Bairamashvili.     

Two New Alkaloids from Fuzi and Their Metabolites Study

Former study suggests alkaloids from herbs of Aconitum genus plants possess excellent bioactivities, which exert great value for related deeper chemical constituent investigation. Herein, chemical isolation was performed and four alkaloids were isolated from Fuzi, of which two were new ones, and the other two were reported NMR data for the first time. Their chemical structures were identified by NMR data, high resolution MS, UV and IR analysis. Additionally, the MS fragmentation patterns were explored, formerly, that of hetisane alkaloid was rarely reported, and fragmentation mechanism of the diagnostic ion was proposed. Based on these fragment pathway, metabolites and metabolic pathways of four compounds were investigated in rat liver microsomes using UPLC−Q/TOF−MS, and dehydrogenation product was firstly found from metabolites of hetisane alkaloid.     

Enhanced anthocyanins and resveratrol production in Vitis vinifera cell suspension culture by indanoyl-isoleucine, N-linolenoyl-L-glutamine and insect saliva

The effects of two synthetic elicitor indanoyl-isoleucine (In-Ile), N-linolenoyl-l-glutamine (Lin-Gln) and one biotic elicitor insect saliva (from Manduca sexta larvae) on plant cell cultures with respect to the induction of secondary metabolite production were investigated. Stimulated production of secondary metabolites, particularly anthocyanins in plant cells and phenolic acids in culture medium, was studied by using suspension culture of Vitis vinifera L. cv. Gamay Fréaux as a model system. In the treatments with In-Ile, the production of anthocyanins was enhanced 2.6-fold. In-Ile, Lin-Gln and saliva significantly elevated the accumulation of phenolic acids, particularly 3-O-glucosyl-resveratrol. The used elicitors did not suppress cell growth. Secondary metabolites were differently responsive to elicitation. 3-O-glucosyl-resveratrol was the predominant phenolic acid in V. vinifera cell culture, and its production was significantly stimulated by saliva, with 7.0-fold of the control level 24 h after treatment. The production of 4-(3,5-dihydroxy-phenyl)-phenol was significantly stimulated by In-Ile with 6.4-fold of the control level 24 h after treatment.