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Callus cultures of the endemic South-African legume Cyclopia subternata were cultivated under varying light and temperature conditions to determine their influence on biomass growth and bioflavonoids accumulation. Experimental modifications of light included complete darkness, light of different spectral quality (white, red, blue and yellow) and ultraviolet C (UVC) irradiation. The calli were also subjected to elevated temperature or cold stress. Among the tested light regimes, cultivation under blue light resulted in the highest levels of hesperidin (H)—118.00 mg 100 g−1 dry weight (DW) on 28 days of experiment, as well as isoflavones: 7-O-β-glucosides of calycosin (CG), pseudobaptigenin (PG) and formononetin (FG)—28.74, 19.26 and 10.32 mg 100 g−1 DW, respectively, in 14-days old calli. UVC irradiation applied on 20 days stimulated the accumulation of H (204.14 mg 100 g−1 DW), CG (31.84 mg 100 g−1 DW) and PG (18.09 mg 100 g−1 DW) in 28 days culture by 140, 46 and 165 %, respectively, without negatively influencing callus growth. Low temperature (13 °C) increased CG content by over 1,500 % (235.29 mg 100 g−1 DW) when applied during the whole 28-days growth cycle, at the same time causing 95 % decrease in culture growth in comparison to reference calli maintained at 24 °C. On the contrary, elevated temperature (29 °C) applied during the second half of the culture period resulted in over 300 and 500 % increase in CG and PG content (61.76 and 58.89 mg 100 g−1, respectively) while maintaining relatively high biomass yield.

High productive suspension cultures of Genista tinctoria were elicited (methyl jasmonate or chitosan) and permeabilised (dimethyl sulfoxide) in order to achieve a plant in vitro system rich in isoflavones, with extracellular storage profile. The maximum concentration of isoflavone aglycones (4–6 times higher than in the controlled biomass) was obtained in the suspension elicited with chitosan. All isoflavonoids were stored inside cells. In case of methyl jasmonate supplementation the total concentration of isoflavone aglycones achieved was the result of the de novo biosynthesis as well as a hydrolysis of the storage ester forms. The presence of chitosan in the medium was only associated with the production of aglycones de novo. The elicitors had no effect on the accumulation and metabolism of the basic glycoside isoflavones in the suspension. The change in the way the isoflavones were stored was achieved after supplementing the growth media with dimethyl sulfoxide. Maximum concentration of isoflavones in the medium was observed in the 7th hour of the experiment. Eventually, a plant growth system was developed, producing over 11% of isoflavones, ejected as a result of chemical permeabilisation, into the growth medium (approx. 80% of total amount of these compounds in the biomass).

Schisandra chinensis plant in vitro cultures were maintained on Murashige and Skoog (MS) medium supplemented with 3 mg/l 6-benzyladenine (BA) and 1 mg/l 1-naphthaleneacetic acid (NAA) in an agar system and also in two different liquid systems: stationary and agitated. Liquid cultures were grown in batch (30 and 60 days) and fed-batch modes. In the methanolic extracts from lyophilized biomasses and in the media, quantification of fourteen dibenzocyclooctadiene lignans identified based on co-chromatography with authentic standards using high-performance liquid chromatography with diode array detection (HPLC-DAD) and/or liquid chromatography with diode array detection and electrospray ionization mass spectrometry (LC-DAD-ESI-MS) methods. For comparison purposes, phytochemical analyses were performed of lignans in the leaves and fruits of the parent plant. The main lignans detected in the biomass extracts from all the tested systems were schisandrin (max. 65.62 mg/100 g dry weight (DW)), angeloyl-/tigloylgomisin Q (max. 49.73 mg/100 g DW), deoxyschisandrin (max. 43.65 mg/100 g DW), and gomisin A (max. 34.36 mg/100 g DW). The highest total amounts of lignans in the two tested stationary systems were found in extracts from the biomass harvested after 30 days of batch cultivation: 237.86 mg/100 g DW and 274.65 mg/100 g DW, respectively. In the agitated culture, the total content reached a maximum value of 244.80 mg/100 g DW after 60 days of the fed-batch mode of cultivation. The lignans were not detected in the media. This is the first report which documents the potential usefulness of S. chinensis shoot cultures cultivated in liquid systems for practical purposes. Electronic supplementary material The online version of this article (doi:10.1007/s00253-015-7230-9) contains supplementary material, which is available to authorized users.

An efficient micropropagation protocol of Cyclopia genistoides (L.) Vent., an indigenous South African shrub of economic importance, was established. In vitro shoot cultures were obtained from shoot tip fragments of sterile seedlings cultured on solid Schenk and Hildebrandt (SH) medium supplemented with 9.84 microM 6-(gamma,gamma-dimethylallylamino)purine (2iP) and 1.0 microM thidiazuron (TDZ). Maximum shoot multiplication rate [(8.2 +/- 1.3) microshoots/explant)] was observed on this medium composition. Prior to rooting, the multiplied shoots were elongated for 60 days (two 30-days passages) on SH medium with one-half sucrose concentration, supplemented with 4.92 microM indole-3-butyric acid (IBA). The rooting of explants was only possible in the case of the elongated shoots. The highest root induction rate (54.8%) was achieved on solid SH medium with one-half sucrose and one-half potassium nitrate and ammonium nitrate concentration, respectively, supplemented with 28.54 microM indole-3-acetic acid (IAA) and 260.25 microM citric acid. The plantlets were acclimatized for 30 days in the glasshouse, with the use of peat/gravel/perlite substrate (1:1:1). The highest acclimatization rate (80%) was obtained for explants rooted with the use of IAA-supplemented medium. The phytochemical profile of the regenerated plants was similar to that of the reference intact plant material. HPLC analyses showed that C. genistoides plantlets obtained by the micropropagation procedure kept the ability to produce xanthones (mangiferin and isomangiferin) and the flavanone hesperidin, characteristic of wild-growing shrubs.

Essential oil from herb and rhizome of Peucedanum ostruthium (L.Koch.) ex DC un­ derwent qualitative and quantitative analyses. The content of the oil obtained by hydrodistil­lation was 0.95% in the herb and 1.25% in the rhizome (per dry weight basis). Gas chroma­ tography (GC) with MS detection and flame ionisation detection showed that the oil from the rhizome contains 39 compounds, of which 29 were identified. Gas chromatography with flame ionisation detection in chiral columns against standard compounds showed the pres­ence of enantiomers of some of the components of the oil. Compounds present in largest quantities are: sabinene (35.2%) of which (+) sabinene accounts for (96.54%) and 4-terpineol (26.6%) of which (+) 4-terpineol accounts for (65.8%). 44 com ponents were found in the herb essential oil, of which 39 compounds were identified. Compounds present in largest quantities were β-caryophyllene (16.1%) and a-hum ulene (15.8%). The content of sabinene in the herb oil was 4.7%. The following compounds were present in the herb oil only as enantiomers: (+) sabinene (4.7%), (-) limonene (4.4%), (-) β-pinene (0.4%). A coumarin (osthole) was detected in both essential oils (5.5% in herb oil and 5.1% in rhizome oil).