The influence of amino acids on the lobeline production of Lobelia inflata L. hairy root cultures

The herb Lobelia inflata L. (Lobeliaceae) containspiperidine alkaloids. The main alkaloid is the pharmacologically-activelobeline. We have studied the effects of alkaloid precursor amino acids (lysineand phenylalanine) on the growth and alkaloid production of hairy root culturesof Lobelia inflata L. The hairy root clone 8009/h7transformed with Agrobacterium rhizogenes strain R 1601wascultivated on B5 solid medium containing lysine (Lys) and phenylalanine (Phe)both in the presence and absence of the growth regulators IAA and kinetin. Onthe medium containing hormones growth was delayed until day 14. The applicationof growth regulators to the B5 media containing amino acids either singly or incombination increased the biomass in all cases. The maximum dry weight wasachieved in a medium containing Phe+Lys and growthregulators. The highest lobeline level (36 g/g) was detectedintissues cultivated on hormone-free medium containing Phe. In hormone-freemedia,lobeline production increased in the presence of either Phe or Lys comparedwiththe control, but the addition of both greatly decreased synthesis. In contrast,the addition of both amino acids to media supplemented with IAA and kinetinincreased lobeline production.     

Enhanced production of azadirachtin by hairy root cultures of Azadirachta indica A. Juss by elicitation and media optimization

Azadirachtin is one of the most potent biopesticides so far developed from a plant sources. Influence of different culture media and elicitation on growth and production of azadirachtin by hairy root cultures of Azadirachta indica was studied. Out of the three media tested, namely Ohyama and Nitsch, Gamborg's and Murashige and Skoog's basal media, hairy roots cultured on Ohyama and Nitsch's basal medium produced maximum yield of azadirachtin (0.0166% dry weight, DW). Addition of biotic elicitor enhanced the production of azadirachtin by approximately 5-fold (0.074% DW), while signal compounds such as jasmonic acid and salicylic acid showed a approximately 6 (0.095% DW) and approximately 9-fold (0.14% DW) enhancement, respectively, in the production of azadirachtin as compared to control cultures on Ohyama and Nitsch medium. Extracts from hairy roots were found to be superior to those from the leaves for antifeedant activity against the larvae of Spodoptera litura.     

Growth and steroidal saponin production in hairy root cultures of Solanum aculeatissimum

Summary Hairy root cultures of Solanum aculeatissimum were established by trans-formation using Agrobacterium rhizogenes strain 15834. Root growth and production of steroidal saponin were investigated under various culture conditions. Transformed roots grew better in Gamborg's B5 medium containing 3 % sucrose under continuous light than in the dark. Also, the roots turned light green when cultured under continuous light. Green hairy roots produced aculeatiside A (6.71mg ·) L^–1 and aculeatiside B (6.39mg · L^–1) after 8 weeks of culture, while no steroidal saponin was detected in hairy roots cultured in the dark. Of the three culture media tested, Gamborg's B5 medium was superior for growth and steroidal saponin production. Growth and steroidal saponin production were enhanced when 100g · L^–1 auxin except for 2,4-D was added to the medium. The addition of 2,4-D inhibited growth. Production of steroidal saponin was highest with NAA. Transformed roots used in this experiment were confirmed that hairy roots examined contain both TL-DNA and TR-DNA region of Ri plasmid by PCR amplification analysis of DNA.Abbreviations MS medium Murashige and Skoog's medium (1962) - B5 medium Gamborg's B5 medium (1968) - LS medium Linsmaier and Skoog's medium(1965) - HPLC High performance liquid chromatography - NAA -Naphthaleneacetic acid - IAA Indole-3-acetic acid - 2,4-D 2,4-Dichlorophenoxyacetic acid - PCR polymerase chain reaction     

Development of shoots and roots in anther-derived callus of Azadirachta indica A. Juss.—a medicinal tree

Callus originated in microsporangial wall layers and connective tissues of anthers containing uninucleate microspores on Nitsch's or Murashige and Skoog's medium supplemented with growth regulators. A higher percentage of cultures (43) produced callus on Nitsch's medium containing 10 M indole-3-acetic acid + 1 M 6-benzyladenine. After 13–15 weeks, green nodular structures and prominent roots developed in 25% of the cultures on Murashige and Skoog's medium + 10 M -naphthaleneacetic acid + 1 M kinetin. Multiple shoots were induced in this anther-derived callus when subcultured on Murashige and Skoog's medium augmented with 4.44 M 6-benzyladenine + 0.53 M -naphthaleneacetic acid along with 18.75 M polyvinylpyrrolidone. The excised shoots formed roots after subculturing on Murashige and Skoog's medium + 4.90 M indole-3-butyric acid + 18.75 M polyvinylpyrrolidone, thus developing complete plantlets. Examination of callusing anthers also revealed two- to multi-celled pollen masses with intact exine.Abbreviations BA 6-benzyladenine - CW coconut water - 2,4-d 2,4-dichlorophenoxyacetic acid - GA₃ gibberellic acid - HCl hydrochloric acid - IAA indole-3-acetic acid - IBA indole-3-butyric acid - KMnO₄ potassium permanganate - MS Murashige & Skoog's medium - NAA -naphthaleneacetic acid - NB Nitsch's medium - PVP polyvinylpyrrolidone     

Production of diosgenin by hairy root cultures ofTrigonella foenum-graecum L.

Hairy root cultures ofTrigonella foenum-graecum L. were established withAgrobacterium rhizogenes strain A₄. The hairy roots produce diosgenin, an important spirostanol for the semi-synthesis of steroid hormones. Fourteen different liquid media were investigated. The fastest growth was obtained in McCown's woody plant (WP) medium supplemented with 3% sucrose; the highest diosgenin content was observed in half-strength WP medium with 1% sucrose (0.040% dry weight), which represents almost twice the amount detected in the 8-month-old non-transformed roots (0.024%). A time-course study in WP liquid media supplemented with 3% sucrose was undertaken. In these conditions, 17 g diosgenin/g fresh weight were produced. The influence of cholesterol, medium pH and chitosan on diosgenin production was tested. The addition of 40 mg/l chitosan elevated the diosgenin content to three times that found in non-elicited hairy roots.Abbreviations MS Murashige and Skoog (1962) medium - WP McCown's woody plant medium     

Initiation of and solasodine production in hairy root cultures of Solanum mauritianum Scop.

Initiation and establishment of hairy root cultures from leaf or seedling hypocotyl explants of Solanum mauritianum Scop., using six strains of Agrobacterium rhizogenes was attempted. Success was only achieved following hypocotyl inoculation with strain LBA 9402. Transformation frequency was very low, with only one instance out of a possible 90 being recorded. Resultant hairy root cultures grew rapidly and could be maintained using a Murashige and Skoog (1962) medium supplemented with 0.1 g L^–1 myo-inositol and 3% sucrose, either as a solid or liquid culture. Under these conditions, the roots had a solasodine content of 126 g g^–1 DW. Lower levels of solasodine and decreased root growth rates were recorded when the medium strength was reduced by half or 3% glucose substituted for the 3% sucrose.Abbreviations MS Murashige and Skoog's (1962) medium     

Enhanced somatic embryogenesis in Selinum candolii DC. under a mineral oil overlay

Cell suspension cultures of Selinum candolii DC. obtained on liquid Murashige & Skoog's medium supplemented with 4.52 M 2,4-D and 1.16 M kinetin when plated on solid medium devoid of 2,4-D proliferated into a callus and subsequently produced 15–20 somatic embryos within 60 days. However, when the plated cells were overlaid with mineral oil, a decrease in callus formation coupled with a four-fold increase in the number of somatic embryos per gram fresh weight of the cells were observed after 30–45 days. Though no significant correlation could be found between the depth of mineral oil overlay and the number of somatic embryos produced, the embryoids that developed under mineral oil showed a lesser degree of secondary embryogenesis than the controls. The somatic embryos could be readily regenerated into plantlets.Abbreviations 2,4-D 2,4 dichlorophenoxyacetic acid - MS Murashige & Skoog's medium     

Plantlet regeneration through different morphogenic pathways in pommelo tissue culture

Pommelo (Citrus grandis Osbeck) plantlets were regenerated through different morphogenic pathways in culture. Multiple shoot regeneration through de novo organogenesis was obtained with epicotyl segments and root cultures. Shoot regeneration was observed in 84% of the midtal epicotyl segments cultured in Murashige and Skoog's medium (MS) with 2.2 M benzyladenine (BA) and 83% of the middle and proximal epicotyl segments cultured on basal medium. Isolated root segments cultured on medium containing 0.089 M BA showed best shoot regeneration at 71% with an average of 3.3 shoots per segment. Callus tissues derived from cotyledon and leaf explants regenerated shoots on BA-enriched medium. Shoots were also obtained at high frequencies from shoot-tip and nodal explants. Roots developed when regenerated shoots were excised and cultured on half strength MS medium with 2.5 M indolebutyric acid.Abbreviations BA 6-Benzyladenine - IBA Indole-3-butyric acid - MS Murashige and Skoog medium - NAA I-Naphthaleneacetic acid - 2,4-d 2,4-Dichlorophenoxyacetic acid     

In vitro shoot proliferation and plant regeneration from kurrat (Allium ampeloprasum var. kurrat) seedlings

Shoots were produced from kurrat seedling and mature plant explants cultured in Murashige and Skoog medium (MS) alone or supplemented with 4.4 M benzyladenine (BA). Shoots were also produced from explants through a two-step procedure. Regenerated shoots were induced to form roots on MS medium with 5 g I^-1 activated charcoal. Plants were successfully established in soil.Abbreviations AC activated charcoal - BA benzyladenine - MS Murashige & Skoog's (1962) medium - 2,4-d 2,4-dichlorophenoxyacetic acid     

Micropropagation,callus and root culture of Phyllanthus urinaria (Euphorbiaceae)

Efficient micropropagation, callus culture and root culture protocols were developed for the medicinal plant Phyllanthus urinaria(Euphorbiaceae) using single node explants. Maximum multiplication (16–20 shoots per explant) was achieved on Murashige and Skoog media supplemented with 5.0 M kinetin. Murashige and Skoog and Anderson Rhododendron media promoted significant shoot culture growth in terms of numbers of shoots and nodes produced per explant. Rooting was achieved with 93–100% of the microshoots on Murashige and Skoog medium without growth regulators, although 1.25–5.0 M -naphthaleneacetic acid significantly increased the number of roots per explant. Regenerated plants were successfully acclimatized and 91% of plantlets survived under ex vitro conditions. Flowering was observed on micropropagated plants after 3–4 weeks of acclimatization. High frequency callus initiation and growth was achieved when single node explants were inoculated in the horizontal position on Murashige and Skoog medium supplemented with 5.0 M indole-3-butyric acid. Other auxins such as 2,4-dichlorophenoxyacetic acid and -naphthaleneacetic acid promoted moderate callus fresh weight increase, when used separately. Root cultures were successfully established on Murashige and Skoog medium containing 1.1 M -naphthaleneacetic acid. The optimized micropropagation, callus culture and root culture protocols offer the possibility to use cell/root culture techniques for vegetative propagation and secondary metabolism studies.     

In vitro propagation of Iphigenia indica,an alternative source of colchicine

The present study involves in vitro propagation of Iphigenia indica (Kunth.) through multiplication of whole corms and corm buds. The whole corms produced very small micro-corms, which developed plants individually whereas corm buds multiplied to produce numerous shoots at variable rates in presence of -naphthaleneacetic acid (NAA) and 6-benzylaminopurine (BAP). The best response in corm and bud multiplication was obtained in Murashige and Skoog's basal medium (MS) supplemented with 2.69 M NAA and 8.88 M BAP. The shoots regenerated were further cultured on MS medium containing NAA and indole-3-butyric acid (IBA) for initiation of roots. MS medium with 5.38 M NAA and 4.92 M IBA induced highest percentage of roots (81%) within 2 weeks in culture.     

Growth and rosmarinic acid accumulation in callus,cell suspension,and root cultures of wild Salvia fruticosa

The accumulation of rosmarinic acid (RA) in Salvia fruticosa callus, cell suspension, and root cultures was studied. For callus induction, leaves excised from microshoots were cultured on MS medium containing thidiazuron (TDZ) (0, 2.3, 4.6, 6.9, 9.2, or 11.5 M) and indole-3-acetic acid (IAA) (0 or 3 M). For root culture, hairy roots were cultured in B5 medium containing 2.7 M -naphthaleneacetic acid (NAA) and different concentrations of sucrose or phenylalanine. Induction of callus was completely inhibited in the absence of both TDZ and IAA and the largest callus (0.79 g) was obtained with a combination of 6.9 M TDZ and 3 M IAA. Culture duration of 5 weeks resulted in maximum callus growth and RA yield (2.12 mg/ 100 mg dry weight). Cell suspension growth and RA yield (5.1 mg/ 100 mg dry weight) were maximum after 20 days of culture. The highest root growth and RA yield (2.62 mg/ 100 mg dry weight) was obtained with 4% (w/ v) sucrose. Incorporation of 10 mg l^–1 phenylalanine in the medium increased RA yield in the roots to 4.68 mg/ 100 mg dry weight after 4 weeks of culture. Amounts of RA extracted from in vivo leaves and roots were 0.21 and 0.72 mg/ 100 mg dry weight, respectively.     

Establishment of hairy root cultures of Psoralea species

Eight Psoralea species (Leguminosae) were inoculated with Agrobacterium rhizogenes, strains 8196 and 9402. Hairy roots were only induced by strain 9402. Attention was focussed on Psoralea lachnostachys. Transformed roots grew very rapidly in Gamborg B5 liquid medium with a doubling time of the culture of 38 hours. Whatever the culture conditions, the two furanocoumarins usually found in roots of Psoralea plants, psoralen and angelicin, were not detected in cultured transformed and non transformed roots even when some chitosan was added to the medium. However, 669 g.g^–1 dry matter of psoralen and 215 g.g^–1 dry matter of angelicin were found in roots from soil grown plants. A possible translocation of these compounds from the aerial parts to the roots is suggested.Abbreviations B5 medium Gamborg's medium (Flow laboratories's formulation) - NAA Naphthaleneacetic acid     

Agrobacterium rhizogens mediated transformation of Rauvolfia serpentina: Regeneration and alkaloid synthesis

Shoot cultures of Rauvolfia serpentina infected with Agrobacterium rhizogenes 15834 produced tumourous tissue at the site of injection, which eventually developed callus with hairy roots. Sporadic shoot formation occurred from the hairy roots. The shoots were grown to maturity in the green house. The mature transformed plants (RST) showed distinct variations in their physiological characteristics. The flowers of the transformed plants were more delicate and less pigmented when compared to the flowers of the mature normal plants. The roots of the transformed plants were hairy with a number of lateral branches, whereas the roots of the normal plant had very few lateral branches. The biomass of the transformed plant was 86.39 g/plant (fresh wt), significantly higher than the normal plant which was 77.3 g/plant (fresh wt). The total alkaloid content in the mature transformed plant (0.073 g per plant) was similar to the normal plant (0.078 g per plant), although the hairy roots contained little alkaloid.Abbreviations MS Murashige & Skoog's basal medium - MLS modified Linsmaier & Skoog's basal medium - BA benzyladenine - NAA naphthalene acetic acid - TLC thin layer chromatography - HPLC high performance liquid chromatography     

Production of valepotriates by hairy root cultures of Centranthus ruber DC

Hairy root cultures of Centranthus ruber DC. were established by infection of sterile plantlets with Agrobacterium rhizogenes, strain R1601. The transformed roots were grown in 12 different, hormone-free liquid media, and valtrate, isovaltrate, 7-desisovaleroyl-7-acetylvaltrate, 7-homovaltrate, didrovaltrate and isovaleroxyhydroxydidrovaltrate were quantified by high performance liquid chromatography. The highest overall valepotriate content (3.0% dry wt) was observed in half-strength Gamborg B5 medium supplemented with 3% sucrose. This concentration is very similar to that found in the roots of parent plants grown in the field. The use of N,N-dimethylmorpholinium iodide, a plant bioregulator, was very detrimental to the hairy root growth and to the valepotriate production. The hairy roots cultured in half strength Gamborg B5 liquid medium supplemented with 3% sucrose for 45 days produced over 31 mg/g dry wt valepotriates.Abbreviations MS Murashige and Skoog medium (Murashige and Skoog 1962) - B5 Gamborg B5 medium (Gamborg 1970) - WP McCown's woody plant medium (Lloyd and McCown 1980) - H Heller's medium (Heller 1953) - 1/4 B5-7 quarter strength B5 + 7% sucrose - DMI N,N-dimethylmorpholmium iodide - VAL valtrate - IVAL isovaltrate - DIA-VAL 7-desisovaleroyl-7-acetylvaltrate - HVAL 7-homovaltrate - DI didrovaltrate - IVHD isovaleroxyhydroxydidrovaltrate (Fig. 1) - NMR nuclear magnetic resonance spectroscopy - HPLC high performance liquid chromatography - Ac acetyl - IV isovaleryl - IV-IV -isovaleryloxy-isovaleryl - MV -methyl-valeryl     

Effects of source of macronutrients and plant growth regulator concentrations on shoot proliferation of Cornus florida

Nodal stem segments of flowering dogwood (Cornus florida L.) were cultured on media containing seven different sources of macronutrients including full- and half-strength Murashige & Skoog (MS) macrosalts, N6, Anderson's (AND), Quoirin & Lepoivre's (LP), Nitsch & Nitsch (NIT), and Woody Plant Medium (WPM). All media contained MS micronutrients, Staba vitamins, 20 g l^-1 sucrose, and 6.5 g l^-1 Difco Bacto-agar, and were supplemented with 2.2 M 6-benzyladenine (BA) and 0.49 M indole-3-butyric acid (IBA). Following three subcultures, the best shoot proliferation was supported on media containing WPM macronutrients. To optimize the proliferation rate, shoots were cultured on WPM macronutrients supplemented with eight combinations of BA and IBA, and 3.3 M BA without IBA was determined to be the best.Abbreviations BA 6-benzyladenine - IBA indole-3-butyric acid     

An interchangeable system of hairy root and cell suspension cultures ofCatharanthus roseus for indole alkaloid production

Hairy roots ofCatharanthus roseus obtained by co-cultivation of hypocotyl segments withAgrobacterium rhizogenes, and cultured in SH (Schenk and Hildebrandt) basal medium, formed two types of calli when subcultured in SH medium with 1 mg/1 -naphthaleneacetic acid and 0.1 mg/l kinetin. One of them, a compact callus, when re-subcultured in SH basal medium gave rise to hairy roots again. A rhizogenic cell suspension culture was established from this type of callus. When cultured in SH medium with growth regulators, the rhizogenic callus produced catharanthine at a level of 41% of the level in the initial hairy roots. Upon transfer to SH basal medium, regenerated hairy roots produced this alkaloid at the original level of 1.5 mg/g dry wt. Using this cell/hairy root interchange system a new management system for hairy root culture in bioreactors has been devised and examined involving production of biomass in the form of a cell suspension in medium supplemented with growth regulators, and catharanthine production by hairy roots regenerated from these cells in medium without growth regulators.Abbreviations NAA -naphthaleneacetic acid - SH Schenk and Hildebrandt - SHNK SH medium + 1 mg 1^–1 NAA + 0.1 mg 1^–1 kinetin     

Variation of alkaloid productivity among several clones of hairy roots and regenerated plants ofAtropa belladonna transformed withAgrobacterium rhizogenes 15834

Hairy root cultures ofAtropabelladonna were established by transformation withAgrobacterium rhizogenes 15834. Five clones of them were employed to study the production of hyoscyamine, the main constituent of the plant, together with other tropane alkaloids. The growth and alkaloid production of each clone were differently affected by basal liquid culture media tested. The transgenic plants regenerated from each clone of the hairy roots had different phenotypes and diverse alkaloid productivity both in the cultured condition and in productivitiy both in the cultured condition and in hydroponics.Abbreviations ANOVA analysis of variance - B5 medium Gamborg B5 medium - BA N⁶-benzyladenine - B.S. Balanced Solution - dw dry weight - EC electric conductivity - fw fresh weight - GC/MS gas chromatography-mass spectrometry - HPLC high performance liquid chromatography - MS medium Murashige and Skoog medium - NAA naphthalene-l-acetic acid - PCR polymerase chain reaction - SDS sodium dodecyl sulfate - TMS trimethylsilyl - WP medium Woody Plant medium     

Production of nematocidal compounds by hairy root cultures of Tagetes patula L.

Summary Marigold (Tagetes patula L.) hairy roots induced by infection with Agrobacterium rhizogenes produced -terthienyl when grown in darkness, and an n-hexane extract of the roots showed nematocidal activity. Depending on the hairy root line used, the level of -terthienyl varied from 15 to 1268 g per g dry weight, a level that corresponded to 0.15 to 12.7-fold that in intact roots. Analysis by HPLC indicated that the nematocidal activity was due predominantly to -terthienyl. However, it is suggested that nematocidal compounds other than -terthienyl are present in hairy roots cultured in the dark for long periods or in the light.