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The aim of our study was to investigate the presence and quantitative contents of lignans in the tissues of Taxus ×media. The presence of the lignans: pinoresinol, matairesinol and secoisolariciresinol was assessed in needles, shoots cultures and suspension culture. Pinoresinol was the only lignan found in the tissue of T. ×media. The total pinoresinol content in the needles and in the shoots was 1.24 mg/g dry weight (dw) and 0.69 mg/g dw, respectively. Most of the pinoresinol identified was appeared glycosidically bound. In needles, the amount of glycosidically bound pinoresinol (0.81 mg/g dw) was about twice as high as that of free pinoresinol (0.43 mg/g dw). The content of free and glycosidically bound pinoresinol showed the level of 0.18 mg/g dw and 0.51 mg/g dw, respectively in the in vitro shoot cultures. In the cell culture, no pinoresinol was found.
Nodal segements were taken from juvenile shoots of mature 100 year-old trees of saucer magnolia (Magnolia x soulangiana Soul.-Bod.) and cultured on Standardi and Catalano medium supplemented with 1.33 µmol·dm⁻³ BA, 0.54 µmol·dm⁻³ NAA, 58 µmol·dm⁻³ sucrose and 6.0 g·l⁻¹ agar-agar. After 8 weeks, separated shoots were transferred to rooting medium with half-strength macronutrients (basal medium) supplemented with 0.3% activated charcoal and one of carbohydrates: arabinose, cellulose, fructose, galactose, glucose, lactose, mannose, rhamnose, ribose, sorbose, sucrose or xylose at 20 g·dm⁻³ and 7.0 g·dm⁻³ agar-agar. After 13 weeks of culture, shoot number, fresh and dry weight of shoots and roots, total root length and number of roots/per shoot were recorded. Percentages of rooted shoots were calculated. Fructose, mannose and xylose were the most effective carbon source on shoot proliferation followed by sucrose. The rooting response was induced by cellulose and xylose. Arabinose, rhamnose and sorbose inhibited root formation. The number of adventitious roots produced per shoot was stimulated by cellulose and xylose. Total biomass (shoot plus roots) of the plantlets was the highest at fructose and cellulose.
This report describes the effect of triacontanol on shoot multiplication and production of antioxidant compounds (carnosic acid, carnosol and rosmarinic acid) in S. officinalis cultures grown on MS basal medium (agar solidified medium supplemented with 0.1 mg l-1 IAA, 0.45 mg l-1 BAP). It was found that shoot proliferation significantly increased when triacontanol at concentrations of 5, 10 or 20 µg l-1 was added to the medium. HPLC analysis of acetone and methanolic extracts of sage shoots showed that the production of diterpenoids, carnosic acid/carnosol ratio, as well as, contents of rosmarinic acid were also affected by the treatment with triacontanol. The highest stimulation effect of triacontanol was observed on the production of carnosol, where the treatment with 20 µg l l-1 increased the content of this diterpenoid 4.5-fold compared to that in the control (sage shoots growing on MS basal medium, only).
Optimization of conditions for hydroquinone biotransformation into its β-ᴅ-glucoside, arbutin, in agitated shoot cultures of Ruta graveolens L. and Hypericum perforatum L. allowed us to obtain a maximum content of this important therapeutic and cosmetic product of 7.8 and 7.2% (dry weight), respectively. These contents are higher than respective values required for standardization of known arbutin-containing plant raw materials according to the European Pharmacopoeia and national pharmacopoeias of European countries.
The shoots of Salvia officinalis growing in MS liquid medium supplemented with IAA 0.1 mg l-1) and BAP (0.45 mg l-1) were treated with methyl jasmonate (MeJA) to increase production of compounds with antioxidant activity (carnosic acid, carnosol and rosmarinic acid). The increase in metabolite production depended on MeJA concentration, the period of exposure to elicitor and type of compound. The MeJA action was observed 24 h after elicitation. It was found that the maximum level of diterpenoids, calculated as the sum of CA and Car (about 8 mg g-1 dry wt) was achieved at 3 days after elicitation with 20 µM methyl jasmonate. The highest amount of rosmarinic acid (about 41 mg g-1 dry wt) was achieved with 50 or 100 μM methyl jasmonate on the 5th day after elicitation. It was almost 2-fold higher compared to the control (cultures treated with only ethanol).
The influence of melatonin (MEL) in comparison with IAA, IBA (all at 5.71 µ M), and auxin-free (0) medium on development of highbush blueberry (Vaccinium corymbosum hort. non L.) ‘Herbert’ in vitro shoot cultures was examined. Depending on the kind of hormone in vitro cultures consisted of various number of axillary (AX) and adventitious (AD) shoots. The influence of melatonin on in vitro cultures was intermediate but more similar to IAA than IBA. Production of axillary shoots on media supplemented with MEL and IAA was comparable and higher than on medium with IBA. In contrast to IAA melatonin reduced development of adventitious shoots. Contrary to IBA-obtained cultures AX shoots grown on ‘IAA’, ‘0’, and ‘MEL’ media resembled AD shoots.
The aim of the work presented was to determine the chlorophyll and anthocyanin accumulation in Clematis pitcheri shoots cultured in vitro at different temperatures on the medium with various sucrose and nitrogen level. Two concentrations of sucrose: 10 g-l-1 and 30 gT1, and two levels of nitrogen compounds: 100% and 50% of standard MS strength, were used. Shoots were cultured at 15°C, 20°C and 25°C. It was found that plantlets of C. pitcheri grown at 20°C contained the highest and at 15°C the lowest content of chlorophyll. The sucrose concentration in the medium had no or only a slight effect. Lower level of nitrogen compounds (50% N) stimulated accumulation of chlorophyll in shoots as compared to a normal strength (100% N), with the highest differences at 15°C. High sucrose (30 g-l-1) and nitrogen (100% N) concentrations and low temperature (15°C) significantly promoted anthocyanins accumulation. Reduction of nitrogen compounds level in the medium to 50% and lowering sucrose concentration to 10 gT1 leads to decrease of anthocyanins accumulation in the shoots cultured at 15°C and 20°C. In the case of explants cultured at 25°C, the sucrose and nitrogen concentration in the medium had no or only a slight effect on accumulation of anthocyanins in the shoots.
The study evaluated two methods of conserving Rubus chamaemorus L. shoot cultures: medium-cold storage and encapsulation of shoot buds. Cold-stored explants were transferred every 12 weeks to proliferation medium and their multiplication rate was observed after the first passage. Shoot cultures stored at 4°C under low light intensities for 12 months without intervening subculture survived with 90% viability. Axillary buds obtained from in vitro shoot culture of cloudberry were encapsulated in calcium alginate hydrogel. Regrowth response of encapsulated buds was estimated. Encapsulated buds stored at low temperature in the dark survived for up to 3 months without loss of viability. The fidelity of subcultured plantlets was also evaluated by phytochemical analysis (fingerprinting) of some phenolic compounds and morphological observations. Preliminary trials in the botanical garden showed that plantlets of Rubus chamaemorus derived in vitro can be used for ex situ germplasm conservation.
Micropropagation of a mature female Taxus cuspidata tree with paclitaxel and cephalomannine content in the needles of 457.6 μg g-1 DW and 340.9 μg g-1 DW, respectively, was elaborated using shoot tips as explants. A new yew clone derived from a seed of the mother plant was also obtained. Single shoots developed from shoot tips on WP mineral basal medium with B5 vitamins (WP-B5) supplemented with 20 mg l-1 BAP and 5 mg l-1 activated charcoal were propagated by 1 cm long segments cultured on hormone-free medium. When WP-B5 medium with 0.3 mg/l 2-iP and 0,1 mg/l IAA was used 92% of shoots rooted within three months. Paclitaxel content in shoots growing on solid medium and in a mist trickling bioreactor was 45.6–86.5 μg g-1 DW. Plantlets from in vitro culture, grown in pots contained 99.0–213.1 μg g-1 paclitaxel and 558.0 μg g-1 DW cephalomannine.
In vitro culture may provide a suitable environment for selection of heavy-metal tolerant plantlets. Such clones of woody plants could be valuable material applicable to soil remediation. In in vitro culture conditions shoots of Daphne jasminea Sibth. & Sm. and Daphne tangutica Maxim. (Thymelaeaceae) were grown on media supplemented with 0.1, 0.5 and 1.0 mM lead nitrate. Level of lead bioaccumulation, growth parameters, content of photosynthetic pigments, and mineral status of cultured shoots were investigated. D. jasminea has grown vigorously on Pb2+-containing media, with growth tolerance index reaching 73–89%, depending on concentration applied, and the highest growth value was obtained in the presence of 1.0 mM lead nitrate. In vitro propagation of D. tangutica shoots was slightly inhibited by lead ions, however the growth tolerance index has increased up to 152% on medium with 1.0 mM Pb(NO3)2. In both studied species the highest content of accumulated lead, as well as the value of bioconcentration factor, were found in shoots grown on 0.1 mM lead nitrate. D. tangutica accumulated over two times as much lead in comparison with D. jasminea. Chlorophyll content in D. jasminea was not affected by applied lead nitrate doses, while in D. tangutica stimulation of chlorophyll, as well as carotenoid, synthesis occurred. In tested concentrations lead nitrate had no toxic effect on the level of shoot nutrition. Detected levels of essential and trace elements were still high enough to maintain undisturbed growth and development of cultured shoots. This is first report confirming the suitability of in vitro selection for obtaining of vigorous, proliferative, tolerant to elevated lead concentration shoots of ornamental Daphne species.
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Multiple shoots of Telekia speciosa were cultivated on MS medium containing 4.44 µM BAP and 0.54 µM NAA, solidified with agar. After eight weeks of culture the shoots were harvested and extracted with methanol. From the methanol extract one pseudoguaianolide – 2,3-dihydroaromaticin and three thymol derivatives: 8-hydroxy-9,10-diisobutyryloxythymol, 10-isobutyryloxy-8,9-epoxythymyl isobutyrate and 10-(2-methylbutyryloxy)-8,9-epoxythymyl isobutyrate were isolated as major secondary metabolites. Moreover, the shoots produced megastigmane and monoterpene glucosides, which were isolated for the first time from the species. The content of 2,3-dihydroaromaticin in the shoot culture was similar to that found in the intact plant, whereas yields of the three thymol derivatives were higher from multiple shoots than from the plants grown in the open field.
Metodę mikrorozmnażania tulipana opracowano dla potrzeb hodowli twórczej i zachowawczej. Celem prezentowanych badań było zwiększenie efektywności formowania i jakości cebul w kulturach pędów in vitro. W badaniach wykorzystano pędy odmiany ‘Blue Parrot’, która w warunkach in vitro formuje cebule niskiej jakości. Badano wpływ kwasu 1-aminocyklopropano-l-karboksylowego (ACC), kwasu 2-chloroetylo-fosfonowego, CEPA), kwasu indolilo-3-octowego (IAA) oraz estru metylowego kwasu jasmonowego (MeJA) na liczbę i masę uzyskanych cebul in vitro oraz efektywność formowania cebul (procent pędów formujących cebule wysokiej jakości nadających się do ukorzeniania). Związki te dodawano oddzielnie lub łącznie do kultur pędów rosnących na zestalonych pożywkach agarowych po 4 (CEPA) lub 8 tygodniach (wszystkie związki) od zakończenia 14-tygodniowego chłodzenia (niska temperatura indukuje proces tuberyzacji). Wykazano, że IAA oraz MeJA istotnie stymulowały formowanie cebul. W kontroli efektywność procesu formowania cebul wynosiła 20%. W kulturach pędów traktowanych IAA notowano nawet większą liczbę wszystkich cebul od liczby tworzących je pędów, jednakże tylko 49% pędów wytworzyło cebule wysokiej jakości (przy stężeniu IAA 2,5 mg‧dm⁻³). Najwięcej takich wartościowych cebul wytworzyły pędy traktowane samym MeJA w stężeniu 25 i 50 µl‧dm⁻³, odpowiednio 55,5% i 61,0%. Spośród traktowań ACC i CEPA, dwukrotnie zastosowanie CEPA w stężeniu 1 mg‧dm⁻³ poprawiło efektywność formowania cebul z 7,5% (kontrola) do 42,5%. Cebule najwyższej jakości (okryte tuniką i z wąską szyjką) notowano w obecności samego MeJA.
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