We used cytological and embryological methods to study reproductive cycle stages in Cerasus fruticosa Pall., Cerasus × eminens (Beck) Buia and Cerasus × mohacsyana (Kárpáti) Janchen from SW Slovakia, focusing on development of the male and female reproductive organs, fertilization processes and embryo formation. We found that reproductive potential was reduced by synergistic effects of negative biotic and abiotic factors. Despite the presence of degenerated, deformed pollen grains and their great variability of shape and size, a sufficient amount of normally developed viable pollen grains developed in anthers of C. fruticosa and C. × mohacsyana. Disturbed microsporogenesis in C. × eminens led to significantly lower production of viable pollen grains. We did not observe serious disturbances during megasporogenesis and megagametogenesis. Lower fruit set was caused by degeneration of ovules as a result of unsuccessful pollination, fertilization failure, or embryo degeneration during its initial development.
Abstract Chromosome numbers for 13 species of Hieracium L. s.str. from Bulgaria, Macedonia, Poland and Romania are given and their metaphase plates are illustrated. Chromosome numbers are published for the first time for H. djimilense s.lat. 2n=3x=27, H. fiekii R. Uechtr. 2n=3x=27, H. glabrescens (F. W. Schultz) Murr 2n=3x=27, H. juranomorphum Zahn 2n=3x=27, H. sparsiflorum subsp. sparsiceps Zahn 2n=3x=27 and H. sparsum subsp. naegelianiforme Behr & Zahn 2n=3x=27.
Abstract In tomato fruits, chlorophyll, lycopene and ß-carotene are mostly responsible for the color. During ripening of tomato fruits, the color of the pericarp changes from green to red as chlorophyll is degraded and carotenoids accumulate. These changes are associated with an increase in respiration and ethylene production. Carotenoid biosynthesis pathway in plants can be disturbed by herbicide fluridone (1-methyl-3-phenyl-5-[3-trifluoromethyl(phenyl)]- 4(1H)-pyridinone), which inhibits the activity of phytoene desaturase, an enzyme responsible for conversion of phytoene to phytofluene. Fluridone is also used as an inhibitor of biosynthesis of abscisic acid (ABA) and strigolactones, and it reduces chlorophyll production in plants. In our research we studied the effect of fluridone on some physiological parameters, such as color, firmness, ethylene production, lycopene and chlorophyll content during ripening of the tomato fruit. Tomato plants cv. Altadena (Syngenta) were cultivated in a greenhouse in controlled temperature and both immature and mature fruits were used for the experiments, performed between August and November 2016. Fluridone at concentrations of 0.1% and 1.0% in lanolin paste was applied as a 2-3 mm stripe from the top to the base of tomato fruits, and as a control a stripe of lanolin was applied in the same way on the opposite side of the fruits. Fluridone at a concentration of 1.0% greatly inhibited lycopene accumulation in the pericarp of tomato fruits from the treated side. The measurements of fruit firmness have shown no significant differences between firmness of the part of the tomato fruits treated with fluridone, and the non-treated ones. Tomato fruits treated with fluridone produced amounts of ethylene similar to those found in control tissues on the opposite side of the same fruit. Fluridone delayed chlorophyll degradation in tomato fruits. The metabolic significance of these findings is discussed with the role of carotenogenesis inhibition in tomato fruit ripening.
Miscanthus ×giganteus Greef et Deu. (Poaceae), a hybrid of Miscanthus sinensis and M. sacchariflorus native to Japan, is an ornamental and a highly lignocellulosic bioenergy crop, cultivated in the European Union as an alternative source of energy. This grass reproduces exclusively vegetatively, by rhizomes or via expensive in vitro micropropagation. The present study was aimed at finding the barriers that prevent sexual seed production, based on detailed embryological analyses of the whole generative cycle, including microsporogenesis, pollen viability, megasporogenesis, female gametophyte development, and embryo and endosperm formation. Sterility of M. ×giganteus results from abnormal development of both male and female gametophytes. Disturbed microsporogenesis (laggard chromosomes, univalents, micronuclei) was further highlighted by low pollen staining. The frequency of stainable pollen ranged from 13.9% to 55.3% depending on the pollen staining test, and no pollen germination was observed either in vitro or in planta. The wide range of pollen sizes (25.5-47.6 μm) clearly indicated unbalanced pollen grain cytology, which evidently affected pollen germination. Only 9.7% of the ovules developed normally. No zygotes nor embryos were found in any analyzed ovules. Sexual reproduction of M. ×giganteus is severely hampered by its allotriploid (2n=3x=57) nature. Hybrid sterility, a strong postzygotic barrier, prevents sexual reproduction and, therefore, seed formation in this taxon.
The pollen morphology of many collections of taxa of the tribe Nigelleae from the family Ranunculaceae which occur worldwide is presented in this study. A total of 88 specimens from 21 taxa, some of which were recently proposed, belonging to the genera Komaroffia, Garidella, and Nigella of Nigelleae were examined using light microscopy (LM) and scanning electron microscopy (SEM). In the tribe, the pollen type is mostly trizonocolpate, but in many taxa and specimens, both trizonocolpate and non-trizonocolpate types occur together. The pollen grains are small to medium (25–53.75 μm × 20–55 μm) in size and oblate to prolate in shape. The exine pattern at the mesocolpium in all the taxa investigated is similar: micro-echinate in LM and micro-echinate-punctate in SEM. The colpus membrane in Komaroffia and Nigella is micro-echinate in both LM and SEM. In Garidella, it is micro-echinate in LM but echinate (spinulose) in SEM. In this study, multivariate analyses, principal component analysis (PCA), and unweighted pair group method with arithmetic mean (UPGMA), were used to evaluate relationships between the genera and species within the tribe with respect to pollen morphology. PCA results show three main groups in the tribe: Garidella, Komaroffia, and Nigella. Moreover, the UPGMA tree also chiefly supports generic segregation into the smaller genera. An overall synthesis of the pollen characteristics of the three genera is provided and discussed.
The aim of our research was to connect the detailed study of fruit anatomy of black crowberry (Empetrum nigrum) with identification and detection of the main non-anthocyanin polyphenolic compounds. Our experimental results showed that the highest accumulation of anthocyanin bodies occurred in mature fruits in outer layers during fruit development. The shape of the anthocyanin bodies was most often globular, spherical, hemispherical and intermediate types were present only occasionally. Mature cells of the gynoecium and pericarp generally contain anthocyanin bodies incorporated inside vacuoles. The observed compounds accumulated in cells were rutin, quercetin and catechins, resveratrol; coumaric, p-coumaric, caffeic, ferulic acids, gallic, vanilic, syringic, cinnamic and caffeic acids. These compounds were selected because of their proposed positive effects on health. The analyses of the polyphenolic spectrum showed predominance of ferrulic acid together with gallic acid and catechins with quercetin.The aim of our research was to connect the detailed study of fruit anatomy of black crowberry (Empetrum nigrum) with identification and detection of the main non-anthocyanin polyphenolic compounds. Our experimental results showed that the highest accumulation of anthocyanin bodies occurred in mature fruits in outer layers during fruit development. The shape of the anthocyanin bodies was most often globular, spherical, hemispherical and intermediate types were present only occasionally. Mature cells of the gynoecium and pericarp generally contain anthocyanin bodies incorporated inside vacuoles. The observed compounds accumulated in cells were rutin, quercetin and catechins, resveratrol; coumaric, p-coumaric, caffeic, ferulic acids, gallic, vanilic, syringic, cinnamic and caffeic acids. These compounds were selected because of their proposed positive effects on health. The analyses of the polyphenolic spectrum showed predominance of ferrulic acid together with gallic acid and catechins with quercetin.
Chromosome numbers for 15 taxa of Hieracium s.lat. (including two taxa of Pilosella Vaill.) from Bosnia and Herzegovina, Bulgaria, Greece, North Macedonia, Poland, Romania and Slovakia are given and their metaphase plates are illustrated. Chromosome numbers are published for the first time for H. pannosum subsp. parnassi Nägeli & Peter from Greece (3x and 4x), and for an undescribed species of H. sect. Cernua from North Macedonia (4x). A new, diploid chromosome number was found in H. bracteolatum s.lat. from Greece.
We studied the effect of qualitative and quantitative variation of saponin content in foliar tissues of four European alfalfa (Medicago sativa L.) cultivars (Radius, Sapko, Sitel, Radius line 1) on pea aphid (Acyrthosiphon pisum Harris) development, and the effect of aphid infestation on alfalfa saponin content. Aphids (adult apterae, larvae, and adult alatae) were counted on 3-, 6- and 9-month-old plants (before the first, second and third cutting). Thin-layer chromatography was used to detect and estimate the quantity of the following saponins: 3GlcA, 28AraRhaXyl medicagenic acid; 3Glc, 23Ara, 28AraRhaXylApi zanhic acid (zanhic acid tridesmoside); and 3RhaGalGlcA soyasapogenol B (soyasaponin I). Radius, Sapko, and Sitel contained all three saponins but Radius line 1 did not contain zanhic acid tridesmoside or medicagenic acid glycoside. Saponin content was highest in Radius and lowest in Radius line 1. Regardless of the cultivar, saponin content was higher in aphid-infested than uninfested plants. For all sampling dates, aphid numbers were highest on Radius line 1 and lowest on Radius; that is, aphid numbers were inversely related to saponin content. Alfalfa has a herbivoreinduced defense. Saponin levels increase in the foliage of infested alfalfa. Attempts of plant breeders to reduce saponin content in order to increase alfalfa digestibility for livestock might make the plants more susceptible to aphids and other pests.
Metal ions can modify plant metabolism and change the level of biologically active components. In the present study, the impact of short-term exposure to strontium on the accumulation of the metal as well as the content of isoflavones in soybean sprouts was investigated. The seeds were germinated in hydroponics with 0, 1, 1.5, 2.5, 5.0, or 10.0 mM of Sr for 72 hours. The content of strontium was assessed using flame atomic absorption spectrometry and the amount of isoflavones was determined with high performance liquid chromatography. Dose-dependent accumulation of Sr and a linear correlation between the Sr concentration in the growth medium and the content of the element in the plant samples were observed. The largest changes in the isoflavone content, compared to the control, were noted in soy sprouts germinated in the presence of 5 and 10 mM of strontium. Daidzin, genistin, malonyldaidzin, and malonylgenistin were the dominant isoflavones and their content increased by approx. 28, 44, 34, and 47%, respectively, compared to the control. Low amounts of aglycones were found; moreover, their content decreased by ca. 19–30%. Our research can be important for obtaining a natural product enhanced with strontium and isoflavones, which contribute to prevention of osteoporosis associated with endogenous oestrogen deficits.
We used artificial hybridization to study the crossability of the noble fir (Abies procera) with Manchurian fir (A. holophylla) and Caucasian fir (A. nordmanniana), and found compatibility between A. procera of North American origin and the Asian species A. holophylla as evidenced by the 14% fraction of filled seeds obtained in A. procera × A. holophylla crossing. Crossing of A. procera with the Mediterranean species A. nordmanniana failed completely, producing only empty seeds.
We explored the use of the medicinally important plant Centella asiatica for expression of hemagglutinin-neuraminidase (HN) protein of Newcastle disease virus (NDV) strain AF2240. HN protein is the principal target for subunit vaccine development against NDV. The full-length HN gene was cloned into a plant expression construct driven by the CaMV 35S promoter and C-terminal fusion of green fluorescence protein (GFP) as reporter system. The recombinant expression construct was transformed via particle bombardment into C. asiatica callus. Transformants were screened using GFP and selected on MS medium supplemented with 15 mg/l hygromycin. The ~1.8 kb HN mRNA transcript was detected on the putative transformants using RT-PCR. The presence of HN protein expression was further confirmed through dot blot analysis using anti-NDV chicken serum. Here we report, for the first time, the use of a novel medicinal plant as a new platform for HN protein expression.
Opening keynote presentation at the 7th International Symbiosis Congress (Kraków, Poland, July 2012), which was dedicated to the memory of Lynn Margulis, outstanding scientist. It is particularly appropriate that this tribute appears in this journal based in Cracow, for shortly before her passing, she told me how very much she looked forward to coming to the Jagiellonian University in Cracow, “the great city of Copernicus”, as the invited keynote speaker to this Congress. DZ
The influence of ambient solar UV-A or UV-B radiation on growth responses was investigated in three varieties of cotton (Gossypium hirsutum L.) after exclusion of solar UV-A/B radiation: JK-35, IH-63 and Khandwa-2. Cotton plants were grown from seeds in UV-exclusion chambers lined with selective UV filters to exclude either UV-B (280-315 nm) or UV-A/B (280-400 nm) from the solar spectrum under field conditions. Excluding UV-B and UV-A/B significantly increased plant height, leaf area and dry weight accumulation in all three varieties of cotton. The varieties differed considerably in their sensitivity to ambient UV-A/B. Khandwa-2 was most sensitive and JK-35 least sensitive to ambient solar UV. We monitored the activity of the antioxidant enzymes superoxide dismutase (SOD), ascorbic acid peroxidase (APX), glutathione reductase (GR) and guaiacol peroxidase (GPX), as well as the level of the antioxidant ascorbic acid (ASA), in primary leaves of the most UV-sensitive variety (Khandwa-2). The level of UV-B-absorbing substances was significantly decreased by exclusion of solar UV-B and UV-A/B. Exclusion of solar UV decreased the activity of all the antioxidant enzymes monitored and the level of ascorbic acid versus control plants (+UV-A/B) grown under filters transparent to solar UV. Reduction of the antioxidant defense after UV exclusion indicates that ambient solar UV exerts significant stress and induces some reactive oxygen species to accumulate, which in turn retards the growth and development of cotton plants. Ambient solar UV stresses cotton plants, shifting their metabolism towards defense against solar UV. Exclusion of solar UV eliminates the need for that defense and leads to enhancement of primary metabolism.
Clarifying the genetic background of the drought-tolerance trait is a crucial task that may help to improve plant performance under stress by a genetic engineering approach. Dehydration-responsive element-binding protein (DREB) is a transcription factor family which modulates many stress-responsive genes. In this study, we isolated a DREB homolog gene named ZmDREBtv from Zea mays var. Tevang-1. Using bioinformatic tools, a number of InDels and SNPs in ZmDREBtv sequence different from the reference accession were identified. In addition, based on deduced protein sequence similarity, ZmDREBtv was assigned to transcription factor DREB2 class as featured by a conserved DNA binding domain - AP2. The ZmDREBtv construct under thecontrol of the rd29A promoter was transformed into a drought-sensitive maize plant, K7 line. The transgenic plants were assessed with reference to molecular and phenotypic characteristics related to the drought-tolenrance trait. The results proved that the maize plants carrying ZmDREBtv gene showed enhanced tolerance and better performance to the water-deficit environment at different stages, compared to the wild-type plants.
We made interspecific crosses to facilitate the introgression of desirable traits of Allium roylei into the Alliumcepa genome. After hand-pollination, 906 interspecific F1Allium cepa × A. roylei plants were obtained by in vitro culture via embryo rescue. Nuclear DNA analysis showed that 97.6% of the regenerants were interspecific F1Allium cepa × A. roylei hybrids. Genomic in situ hybridization (GISH) showed that each hybrid had 16 chromosomes, eight of which were identified as A. cepa and eight as A. roylei chromosomes.
In this study, we examined whether and to what extent oxidative stress is induced in seedlings of two winter triticale (Triticosecale Wittm.) varieties (susceptible Tornado and resistant Witon) in response to infestation by the cereal grain aphid (Sitobion avenae L.) and bird-cherry-oat aphid (Rhopalosiphum padi L.). We compared the level of hydrogen peroxide (H2O2) and lipid peroxidation products as well as markers of protein damage (protein-bound thiol and carbonyl groups). The studied parameters were measured at 6, 24, 48 and 96 h post-initial aphid infestation compared to the non-infested control seedlings. Our studies indicated that the cereal aphid feeding evoked oxidative stress in the triticale seedlings. Cereal aphid feeding increased the H2O2 level in triticale tissues, with maximum levels observed at 24 and 48 h post-infestation. Triticale infestation with aphids also increased lipid peroxidation products in triticale seedlings, with the maximal levels at 48 or 96 h post-infestation. Further, there was a reduction in protein thiol content and an increase in protein carbonyl content in the triticale seedlings after infestation with female aphids. Stronger triticale macromolecule damages were evoked by the oligophagous aphid R. padi. There was a more substantial protein thiol content reduction in the resistant Witon cultivar and higher accumulation of protein-bound carbonyls in the tissues of the susceptible Tornado cultivar. The changes were proportional to the aphid population and the time of aphid attack. These findings indicate that the defensive strategies against cereal aphid (S. avenae and R. padi) infestation were stimulated in triticale Tornado and Witon seedlings. Our results explain some aspects and broaden the current knowledge of regulatory mechanisms in plant-aphid interactions.
The free-living Acanthamoeba sp. causes various diseases. Treatment of them is very difficult and not always effective because of encystation, making it highly resistant to antiamoebic drugs. Gram-positive bacteria Staphylococcus aureus, Gram-negative bacteria Escherichia coli, and an yeast Candida albicans also exhibit outstanding resistance to antimicrobial substances. The search for new natural amoebicidal and antimicrobial agents of plant origin is still of current interest. The aim of the study was to investigate the amoebicidal activity of the extracts obtained from tissue culture and a field-grown plant of Chaenomeles japonica against pathogenic trophozoites of Acanthamoeba spp. and antimicrobial effect against S. aureus, E. coli, and C. albicans. The extracts of C. japonica had an inhibitory effect on the proliferation of Acanthamoeba trophozoites as compared to the non-treated control. Among the crude extracts tested, the extract of leaves, from both shoot culture and the field-grown plant had remarkable amoebicidal action against the trophozoites but also antibacterial activity against Gram-positive bacteria Staphylococcus aureus. The extract from leaves from shoot culture, already on the second and third days of treatment, showed an antiamoebicidal effect at a concentration of 1 mg mL-1 (inhibition of trophozoites 87.5% and 91.8%, respectively). In addition to leaves from shoot culture (a conc. 5 mg mL-1, 2nd day inhibition of trophozoites 85.7% and 3rd day 97.2%), leaves from a field-grown plant (a conc. 5 mg mL-1, 2nd day 91.0% and 3rd day 94.4%) and callus (a conc. 5 mg mL-1, 2nd day 90.0% and 3rd day – 95.4%) also exhibited a good antiamoebicidal activity. Out of the four extracts, the extracts from leaves from both shoot culture and a field-grown plant were reported to be the most active against Gram-positive S. aureus, which was determined by the values of MIC = 5.0 mg mL-1 and MIC = 2.5 mg mL-1, respectively. The inhibitory potential depends on the yield and composition of mainly bioactive compounds: pentacyclic terpenoids (mainly betulinic, ursolic, and oleanolic acids) and polyphenols (mainly chlorogenic acid and its isomers, epicatechin, dimeric, and trimeric proanthocyanidins, quercetin and kaempferol derivatives).
The flowers of Polemonium caeruleum are protandrous. The nectary is in the form of a rim encircling the ovary. Secreted nectar accumulates in a chamber located at the bottom of the floral tube and is protected by dense staminal hairs. The nectary tissue is not vascularized, but is supplied by vascular strands that occur near the base of the nectary and which directly supply the stamens. Nectar is secreted via modified stomata located on the upper part of the rim, particularly on the adaxial surface. The number of stomata and the volume and sugar concentration of nectar are greater during the female stage than during the male stage. In both stages, however, the nectar is sucrose-dominant. This paper shows that in P. caeruleum the nectar sugars are not a direct product of current photosynthesis, since plastids of nectary cells are devoid of chlorophyll. The main source of sugars in secreted nectar is the phloem sap, together with starch that accumulates in the nectary cells during the male stage and is then rapidly hydrolyzed during the female stage.
SDS-PAGE electrophoresis was used to study the effect of NaCl on protein expression in two cultivars of tomato (Solanum lycopersicum L.): Edkawi (salt-tolerant) and Castle rock (salt-sensitive). Five-day-old seedlings were grown on MS agar media supplemented with 0, 50, 100, 150, 200 and 300 mM NaCl. Two days after treatment the seedlings were examined to determine the effect of salt on their growth and to relate that to protein banding variations. Gel analysis showed differences in at least 4 protein bands with molecular weights at 20, 25, 45 and 65 kDa. These proteins were induced in the 50 mM NaCl treatment in the salt-sensitive cultivar, then decreasing to undetectability at higher concentrations. In the salt-tolerant cultivar, most of the proteins exhibited a more or less steady expression pattern and maintained expression through the 200 mM NaCl treatment. All proteins gave weak or no expression signals at 300 mM NaCl, the treatment that proved lethal. Differentially expressed bands were identified using MALDI-TOF mass spectrometry. The putative function of each identified protein in relation to salt stress is discussed.
We studied the embryology of Withania somnifera (L.) Dunal by light microscopy in order to reveal specific embryological features of the genus, and compared the results with embryological data on other members of the family Solanaceae. The key embryological characters of W. somnifera include dicotyledonous-type anther wall formation, simultaneous cytokinesis in pollen mother cells, binucleate tapetal cells, 2-celled mature pollen, anatropous, tenuinucellate and unitegmic ovules, polygonum-type embryo sac formation, the presence of an endothelium, and cellular endosperm formation. We give the first report of the dicotyledonous mode of anther wall formation (previously described as basic type) for the species. Comparative study suggests that anther wall formation, number of nuclei in tapetal cells, number of cells in mature pollen, mode of embryo sac formation and endosperm development are the most variable embryological features in Solanaceae. Some of these embryological features of W. somnifera should be of value for comparative study of related species and their phylogenetic relationships within the family.
We used DPPH scavenging assays to study the antioxidant activity of three native Polish species of blackberry leaves (Rubus kuleszae Ziel., R. fabrimontanus (Sprib.) Sprib. and R. capitulatus Utsch.). All the studied extracts (methanolic, water, methanolic-water) showed high DPPH free radical scavenging activity (IC50 450.0-186.0 μg/ml). The most effective of the studied species was Rubus kuleszae. Total content of phenolic compounds (70.50-136.04 mg GAE/g) and phenolic acids (14.70-38.26 mg CAE/g) was determined spectrophotometrically. Antioxidant activity correlated positively with total content of phenolic compounds and phenolic acids.
We examined the response of plants of various crop and weed species to cyanamide in order to evaluate allelochemical- mediated interactions between the species. We studied germination and seedling growth in the common weeds Galium aparine L. and Amaranthus retroflexus L., and the crops Zea mays L., Triticum aestivum L., Lactuca sativa L., Solanum lycopersicum L. and Sinapis alba L. as acceptor plants. Concentration-dependent phytotoxic effects of cyanamide were noted during seed germination and in the root and shoot growth of the tested plants. The monocotyledonous plants generally were less sensitive to cyanamide treatment. Seed germination and seedling growth of the dicotyledonous plants were strongly inhibited by the allelochemical at both tested concentrations (1.2 mM, 3 mM). We conclude that cyanamide has potential for use as a natural herbicide only in specific field systems of cyanamide-tolerant monocotyledonous crops accompanied by cyanamide-sensitive dicotyledonous weeds.
This study investigated the quantitative anatomy of photosynthetic tissues (leaf mesostructure) of wild ginseng Panax ginseng C.A. Mey. (Araliaceae) plants from different natural habitats. The structural and functional traits of the photosynthetic apparatus shown to be especially elastic were mesophyll cell volume (Cv >40%) and traits related to filling of the leaf with cells and plastids (Cv≥21%). P. ginseng possesses relatively few cells per leaf area (44.6-107.2 103/cm2) and chloroplasts (1.7-4.9 106/cm2). Also low are the values of such integral indexes as relative surface of mesophyll cells (Ames/A, 2.78-5.28) and relative surface of chloroplasts (Achl/A, 1.9-3.2). The leaf mesostructure of wild ginseng shows traits of a plant typically found in shady forest habitats. The photosynthetic apparatus of ginseng adapts to various habitat conditions on the level of leaf mesostructure, through structural transformations of mesophyll tissue, such as changes in the number and size of cells and chloroplasts and also the integral surface indexes Achl/A and Ames/A.
Using four Polish Vicia faba L. minor cultivars (Bronto, Dino, Tibo, Nadwiślański) we obtained callus from epicotyl fragments collected from 7- and 14-day-old seedlings and from cotyledonary nodes of immature seeds. Callus induction efficiency varied from 81% to 97% depending on the origin of the explant. Shoots regenerated only from the cotyledonary nodes of all tested cultivars. On average, 50% of the explants grown on MS medium containing 1.0 mg dm-3 NAA, 0.5 mg dm-3 BAP, 0.25 mg dm-3 GA3, 1.0 g dm-3 casein hydrolysate, 750 mg dm-3 inositol, 3% sucrose and 0.4% agar were able to regenerate shoots. The number of calluses regenerating shoots was highest from explants collected from fruiting nodes 6 to 9. Decapitation of donor plants increased the percentage of calluses regenerating shoots. On half-strength MS medium with 2 mg dm-3 NAA and on 1/2 MS alone, 11% of the shoots rooted; on 1/2 MS with 1 g dm-3 AC, 8.0% rooted. The regenerants were transferred to Perlite with Hoagland medium and acclimated. Ten percent of the regenerated plants survived the acclimation process, flowered and produced seeds.
The chemical composition and bioactivity of a water/methanol extract prepared from aerial parts of Circaea lutetiana were determined. HPLC-DAD-MS3 analysis revealed the presence of 14 different compounds comprising phenolic acids, ellagitannins and flavonoids. Antioxidant assays showed the extract's strong scavenging activity towards DPPH (SC50 33.1±3.1 μg/ml), O2 - (SC50 4.0±2.3 μg/ml) and H2O2 (SC50 below 2 μg/ml). Enzyme-based studies revealed that Circaea lutetiana extract inhibits the activity of hyaluronidase (IC50 13.3±2.4 μg/ml) and lipoxygenase (IC50 44.7±1.4 μg/ml). These results support some traditional uses of Circaea lutetiana.