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At least 109 records · Page 6Linked to original sources
PubMed2004

Cadmium(II) and zinc(II) adsorption by the aquatic moss Fontinalis antipyretica: effect of temperature, pH and water hardness.

The biosorption of cadmium(II) and zinc(II) ions onto dried Fontinalis antipyretica, a widely spread aquatic moss, was studied under different values of temperature, initial pH and water hardness. The equilibrium was well described by Langmuir adsorption isotherms. Maximum biosorption capacity of cadmium was independent on temperature and averaged 28.0 mg g(-1) moss, whereas for zinc, capacity increased with temperature, from 11.5 mg g(-1) moss at 5 degrees C to 14.7 mg g(-1) moss at 30 degrees C. Optimum adsorption pH value was determined as 5.0 for both metal ions. Cadmium uptake was unaffected by the presence of calcium ions, but zinc sorption was improved when water hardness increased from 101.1 to 116.3 mg CaCO(3)l(-1). Inversely, as hardness increases, the competition with calcium ions strongly reduces the affinity of the biosorbent for zinc.

Adsorption↗
PubMed2003

Effects of seven pure flavonoids from mosses on germination and growth of Tortula muralis HEDW (Bryophyta) and Raphanus sativus L (Magnoliophyta).

Dried mosses (five moss species) were progressively extracted and subjected to a four-step Craig distribution. Seven pure flavonoids were isolated and identified. The flavonoids were the flavones apigenin, apigenin-7-O-triglycoside, lucenin-2, luteolin-7-O-neohesperidoside, saponarine and vitexin; and the biflavonoid bartramiaflavone and they were submitted to biological tests. The tests were performed in vitro on spore germination and protonemal growth of the moss Tortula muralis and on seed germination and root growth of Raphanus sativus. Flavonoids caused a decrease in the percentage of spore germination, protonemal development and root growth. In addition they caused morphological alterations, such as forked tips, swollen apices, rounded cells and early formation of brood cells in the protonemata. Data were discussed in relation to the presence of allelochemicals in mosses.

Brassica↗
PubMed2003

The use of mosses as environmental metal pollution indicators.

The possibility of using mosses as environmental indicators of metal pollution has been investigated. Mosses of the species Bryum argenteum were collected from different parts of Piedmont (Italy), ranging from highly polluted areas to nearly uncontaminated mountain areas. Periodical samplings were planned in every site on a monthly base, in order to check variations of metal uptake throughout one year; correlations with pluviometric and thermal patterns were investigated for all sampling stations. On every moss sample 20 elements, ranging from major (K, P, Al, Ca, Fe and Mg) to minor (Mn, Na, Ti and Zn) and trace (As, Ba, Cd, Co, Cr, Cu, Li, Ni, Pb and Sr), were quantitatively determined by inductively coupled plasma-atomic emission spectrometry or graphite furnace-atomic absorption spectrometry, depending on the needed sensitivity. Statistical analyses, carried out with principal component analysis and cluster analysis methods, revealed that a good correlation exists between metal content in mosses and pollution degree in the areas sampled.

Bryopsida↗
PubMed2004

Atmospheric metal deposition in a moss data correlation study with mortality and disease in the Netherlands.

The present paper addresses the correlations between moss metal concentrations and epidemiological data on health and mortality rates in The Netherlands. Attention was given to both total and fractionated metal concentrations in the moss tissues, the latter by factor-analytical (mathematical) approaches, and to both grouped and specific diseases. Better than 95% probability correlations were found both for total moss elements and mortality due to specific diseases and for fractionated moss elements and mortality rates summed for grouped diseases. Overall, the presented data suggest that correlation studies between biomonitoring data on metal air pollution and (epidemiological) health data may prove valuable in turning attention to specific metal-health issues and in directing further study into possible dose-response mechanisms in air-associated metal epidemiology.

Air Pollutants↗
PubMed2002

Historical trends in the lead isotopic composition of archival Sphagnum mosses from Scotland (1838-2000).

The analysis of almost 200 Scottish Sphagnum moss samples collected over the past 170 years has revealed trends in the isotopic composition of lead similar to those previously established for dated Scottish lake sediments and peat bogs, lending credibility to these proxy records of atmospheric lead contamination and deposition. The effect of temporal variations in contributions from sources such as smelting of indigenous lead ores (206Pb/207Pb approximately 1.16-1.18), coal combustion (206Pb/207Pb approximately 1.17-1.19), and the use of imported Australian lead (206Pb/207Pb approximately 1.04) was clearly seen in the Scottish moss 206Pb/207Pb record. This showed some differences from the corresponding archival herbage record for the south of England, where the initial influence of Australian lead occurred earlier, at the end of the 19th century. A significant decline from a 206Pb/ 207Pb value of approximately 1.17 in the Scottish moss record began in the 1920s and continued until the 1980s (206Pb/207Pb approximately 1.12). The success of measures to reduce lead emissions to the atmosphere over the past 20 years in the U.K., in particular from petrol-engined vehicles using alkyl lead additives manufactured primarily from Australian lead, is evident in both the increasing 206Pb/207Pb ratio and falling lead concentration data for Scottish moss.

Bryopsida↗
PubMed2003

Trace element contamination in industrial regions of Poland studied by moss monitoring.

The use of terrestrial mosses as biomonitors in large-scale multi-element studies of heavy metal deposition from the atmosphere is a well established technique in Europe. In such studies it is advantageous to determine as many elements as possible in order to distinguish between different source categories. A combination of INAA and AAS has been found very useful in this respect, in particular when epithermal activation is used for instrumental neutron activation analysis. A total of 33 elements (Al, Cl, Sc, V, Cr, Mn, Fe, Co, Ni, Cu, Zn, As, Se, Br, Rb, Sr, Ag, Cd, Sb, I, Cs, Ba, La, Ce, Tb, Yb, Hf, Ta, W, Au, Pb, Th, and U) in Pleurozium schreberi (Brid.) Mitt. moss samples from the Silesia-Kraków Industrial Region and Legnica-Głogów Copper Basin and from the control (background) area in Northeast Poland were identified. The highest concentrations of the majority of trace elements were found in mosses growing in the Silesia-Kraków Industrial Region, only Cu and As concentrations were higher in mosses in the Legnica-Głogów Copper Basin. These results are in conformity with the load of trace elements emissions in these areas.

Bryophyta↗
PubMed2005

Glyco-engineering of moss lacking plant-specific sugar residues.

The commercial production of complex pharmaceutical proteins from human origin in plants is currently limited through differences in protein N-glycosylation pattern between plants and humans. On the one hand, plant-specific alpha(1,3)-fucose and beta(1,2)-xylose residues were shown to bear strong immunogenic potential. On the other hand, terminal beta(1,4)-galactose, a sugar common on N-glycans of pharmaceutically relevant proteins, e.g., antibodies, is missing in plant N-glycan structures. For safe and flexible production of pharmaceutical proteins, the humanisation of plant protein N-glycosylation is essential. Here, we present an approach that combines avoidance of plant-specific and introduction of human glycan structures. Transgenic strains of the moss Physcomitrella patens were created in which the alpha(1,3)-fucosyltransferase and beta(1,2)-xylosyltransferase genes were knocked out by targeted insertion of the human beta(1,4)-galactosyltransferase coding sequence in both of the plant genes (knockin). The transgenics lacked alpha(1,3)-fucose and beta(1,2)-xylose residues, whereas beta(1,4)-galactose residues appeared on protein N-glycans. Despite these significant biochemical changes, the plants did not differ from wild type with regard to overall morphology under standard cultivation conditions. Furthermore, the glyco-engineered plants secreted a transiently expressed recombinant human protein, the vascular endothelial growth factor, in the same concentration as unmodified moss, indicating that the performed changes in glycosylation did not impair the secretory pathway of the moss. The combined knockout/knockin approach presented here, leads to a new generation of engineered moss and towards the safe and flexible production of correctly processed pharmaceutical proteins with humanised N-glycosylation profiles.

Base Sequence↗
PubMed2005

Transcript profiling in plastid arginine tRNA-CCG gene knockout moss: construction of Physcomitrella patens plastid DNA microarray.

The moss Physcomitrella patens is a newly established model plant that is widely used for the characterization of gene function by targeted gene knockout or over-expression. The target gene disruption occurs in both the nuclear and chloroplast genomes. We applied DNA microarray technology to the P. patens plastid genome for large-scale analysis of transcripts. A microarray was constructed containing 108 DNA fragments to detect all annotated plastid genes. We analyzed the transcript profile in a knockout transformant for the arginine tRNA gene, trnR-CCG, and confirmed previous results that rbcL and psaI transcripts accumulate in similar levels to wild-type moss, and accD transcript level is higher than those of wild-type moss. Additionally, the plastid DNA microarray revealed that most plastid genes were expressed at similar levels in wild-type and transformant mosses. This indicates that trnR-CCG is not essential for the expression of plastid genes.

Base Sequence↗
PubMed2005

Image analysis supported moss cell disruption in photo-bioreactors.

Diverse methods for the disruption of cell entanglements and pellets of the moss Physcomitrella patens were tested in order to improve the homogeneity of suspension cultures. The morphological characterization of the moss was carried out by means of image analysis. Selected morphological parameters were defined and compared to the reduction of the carbon dioxide fixation, and the released pigments after cell disruption. The size control of the moss entanglements based on the rotor stator principle allowed a focused shear stress, avoiding a severe reduction in the photosynthesis. Batch cultures of P. patens in a 30.0-l pilot tubular photo-bioreactor with cell disruption showed no significant variation in growth rate and a delayed cell differentiation, when compared to undisrupted cultures. A highly controlled photoautotrophic culture of P. patens in a scalable photo-bioreactor was established, contributing to the development required for the future use of mosses as producers of relevant heterologous proteins.

Algorithms↗
PubMed1997

[Icelandic moss lozenges in the prevention or treatment of oral mucosa irritation and dried out throat mucosa].

BACKGROUND: Icelandic Moss (Cetraria islandica) has been used to treat inflammation and dryness of the pharyngeal mucosa in the naturopathy for many years. It contains substances with protective and antiinflammatory effects for the oral mucosa. The necessary concentration of Icelandic Moss and its therapeutic effectiveness were analysed in this clinical study. METHODS: Sixty-one patients who recently underwent surgery of nasal septum were evaluated for this randomized study. These patients suffer especially from dryness and inflammation of the oral cavity due to breathing only through the mouth while the nose is permanently closed by a nasal package. Three groups of patients treated with three different concentrations of the active substance were compared, Coating, dryness, and inflammation of the mucosa, lymph nodes, tongue, the tolerance of the drug, and symptoms like hoarseness and sore throat were documented. The oral application was performed from the first to the fifth day after the operation. RESULTS: The treatment with Icelandic Moss caused a direct reduction of the observed pathological changes. There were no significant differences between the three test groups. A dose of 0.48 g per day (10 Isla-Moos lozenges per day) is a sufficient treatment. CONCLUSIONS: Icelandic Moss is an advisable therapeutic opportunity without interactions and side effects for the treatment of inflammation of the oral mucosa occurring after nasal surgery, after intubation, and for simple infections of the throat.

Adolescent↗
PubMed2002

[Lead and zinc recovery by adsorption on peat moss during municipal incinerator used lime decontamination].

The objective of this research was to evaluate the efficiency of peat moss for lead and Zn recovery from alkaline leachates (pH 11.5) produced during decontamination of municipal incinerator fly ash. Tests carried out with peat moss columns (density of 0.13 g m l(-1)) gave very high removal yields for lead (98.9 to 100%) and Zn (98.4 to 99.8 %). The initial metal concentrations in the leachates were 126 to 138 mg Pb l(-1) and 14.4 to 23.5 mg Zn l(-1). The columns were fed using two rates (20 and 40 ml min(-1)), which correspond respectively to 17.6 and 8.8 min as contact time on peat moss. Adsorption efficiencies of 16 to 18 mg Pb g(-1) and 1.7 to 3.2 mg Zn g(-1) have been measured during this fly ash leachate treatment study. The adsorbed toxic metals can be desorbed using a chlorhydric acid solution. The peat moss can be regenerated and reused for several adsorption cycles without loss of the lead and Zn adsorption efficiencies.

Adsorption↗
PubMed2006

Effects of de- and rehydration on food-conducting cells in the moss Polytrichum formosum: a cytological study.

BACKGROUND AND AIMS: Moss food-conducting cells (leptoids and specialized parenchyma cells) have a highly distinctive cytology characterized by a polarized cytoplasmic organization and longitudinal alignment of plastids, mitochondria, endoplasmic reticulum and vesicles along endoplasmic microtubules. Previous studies on the desiccation biology of mosses have focused almost exclusively on photosynthetic tissues; the effects of desiccation on food-conducting cells are unknown. Reported here is a cytological study of the effects of de- and rehydration on food-conducting cells in the desiccation-tolerant moss Polytrichum formosum aimed at exploring whether the remarkable subcellular organization of these cells is related to the ability of mosses to survive desiccation. METHODS: Shoots of Polytrichum formosum were dehydrated under natural conditions and prepared for transmission and scanning electron microscopy using both standard and anhydrous chemical fixation protocols. Replicate samples were then fixed at intervals over a 24-h period following rehydration in either water or in a 10 microM solution of the microtubule-disrupting drug oryzalin. KEY RESULTS: Desiccation causes dramatic changes; the endoplasmic microtubules disappear; the nucleus, mitochondria and plastids become rounded and the longitudinal alignment of the organelles is lost, though cytoplasmic polarity is in part retained. Prominent stacks of endoplasmic reticulum, typical of the hydrated condition, are replaced with membranous tubules arranged at right angles to the main cellular axis. The internal cytoplasm becomes filled with small vacuoles and the plasmalemma forms labyrinthine tubular extensions outlining newly deposited ingrowths of cell wall material. Whereas plasmodesmata in meristematic cells at the shoot apex and in stem parenchyma cells appear to be unaffected by dehydration, those in leptoids become plugged with electron-opaque material. Starch deposits in parenchyma cells adjoining leptoids are depleted in desiccated plants. Rehydration sees complete reestablishment over a 12- to 24-h period of the cytology seen in the control plants. Oryzalin effectively prevents leptoid recovery. CONCLUSIONS: The results point to a key role of the microtubular cytoskeleton in the rapid re-establishment of the elaborate cytoplasmic architecture of leptoids during rehydration. The reassembly of the endoplasmic microtubule system appears to dictate the time frame for the recovery process. The failure of leptoids to recover normal cytology in the presence of oryzalin further underlines the key role of the microtubules in the control of leptoid cytological organization.

Acclimatization↗
PubMed2002

Two ancient classes of MIKC-type MADS-box genes are present in the moss Physcomitrella patens.

Characterization of seven MADS-box genes, termed PPM1-PPM4 and PpMADS1-PpMADS3, from the moss model species Physcomitrella patens is reported. Phylogeny reconstructions and comparison of exon-intron structures revealed that the genes described here represent two different classes of homologous, yet distinct, MIKC-type MADS-box genes, termed MIKC(c)-type genes-"(c)" stands for "classic"-(PPM1, PPM2, PpMADS1) and MIKC(*)-type genes (PPM3, PPM4, PpMADS2, PpMADS3). The two gene classes deviate from each other in a characteristic way, especially in a sequence stretch termed intervening region. MIKC(c)-type genes are abundantly present in all land plants which have been investigated in this respect, and give rise to well-known gene types such as floral meristem and organ identity genes. In contrast, LAMB1 from the clubmoss Lycopodium annotinum was identified as the only other MIKC(*)-type gene published so far. Our findings strongly suggest that the most recent common ancestor of mosses and vascular plants contained at least one MIKC(c)-type and one MIKC(*)-type gene. Our studies thus reveal an ancient duplication of an MIKC-type gene that occurred before the separation of the lineages that led to extant mosses and vascular plants more than about 450 MYA. The identification of bona fide K-domains in both MIKC(*)-type and MIKC(c)-type proteins suggests that the K-domain is more ancient than is suggested by a recent alternative hypothesis. MIKC(*)-type genes may have escaped identification in ferns and seed plants so far. It seems more likely, however, that they represent a class of genes which has been lost in the lineage which led to extant ferns and seed plants. The high number of P. patens MADS-box genes and the presence of a K-box in the coding region and of some potential binding sites for MADS-domain proteins and other transcription factors in the putative promoter regions of these genes suggest that MADS-box genes in mosses are involved in complex gene regulatory networks similar to those in flowering plants.

Amino Acid Sequence↗
PubMed1995

Reversible Photoinhibition in Antarctic Moss during Freezing and Thawing.

Tolerance of antarctic moss to freezing and thawing stress was investigated using chlorophyll a fluorescence. Freezing in darkness caused reductions in Fv/Fm (ratio of variable to maximum fluorescence) and Fo (initial fluorescence) that were reversible upon thawing. Reductions in Fv/Fm and Fo during freezing in darkness indicate a reduction in the potential efficiency of photosystem II that may be due to conformational changes in pigment-protein complexes due to desiccation associated with freezing. The absorption of light during freezing further reduced Fv/Fm and Fo but was also reversible. Using dithiothreitol (DTT), which inhibits the formation of the carotenoid zeaxanthin, we found reduced flurorescence quenching during freezing and reduced concentrations of zeaxanthin and antheraxanthin after freezing in DTT-treated moss. Reduced concentrations of zeaxanthin and antheraxanthin in DTT-treated moss were partially associated with reductions in nonphotochemical fluorescence quenching. The reversible photoinhibition observed in antarctic moss during freezing indicates the existence of processes that protect from photoinhibitory damage in environments where freezing temperatures occur in conjunction with high solar radiation levels. These processes may limit the need for repair cycles that require temperatures favorable for enzyme activity.

Journal Article↗
PubMed1977

Water Stress and Protein Synthesis: V. Protein Synthesis, Protein Stability, and Membrane Permeability in a Drought-sensitive and a Drought-tolerant Moss.

The effects have been studied of water stress and desiccation on protein synthesis in the drought-tolerant moss Tortula ruralis and the drought-sensitive moss Hygrohypnum luridum. At any particular level of steady state water stress, the inhibition of protein synthesis was greater in H. luridum than in T. ruralis. Water stress-induced changes in the pattern of protein synthesis, as determined by the double label ratio technique, were minor in T. ruralis, but major in H. luridum. Proteins of both mosses were found to be stable during desiccation and subsequent rehydration. Changes in membrane permeability, as indicated by the leakage of amino acid, were observed during rehydration of desiccated moss and were dependent on the rate of desiccation. The leakage was small and reversible in T. ruralis but large and irreversible in H. luridum. Although H. luridum failed to recover from complete desiccation (80% loss in fresh weight), it was able to recover fully from steady state stress under conditions where a maximum loss of 55% in fresh weight was recorded.

Journal Article↗
PubMed2004

Content of oak moss allergens atranol and chloroatranol in perfumes and similar products.

Chloroatranol and atranol have been identified as the main allergens in the fragrance material of botanical origin, oak moss absolute. A previous study has shown that nearly all individuals sensitized to chloroatranol will elicit to 5 microg/ml. in a repeated open application test and that 50% will get a reaction to 0.15 micro g/ml under patch test conditions. Thus, chloroatranol is known as a potent allergen. The aim of the current investigation was to quantify exposure to chloroatranol and the chemically related substance atranol in some popular perfumes, eaux de parfum and eaux de toilette available on the European market. In total, 31 products were analysed by liquid chromatography-electrospray ionization-tandemmass spectrometry (LC-ESI-MS-MS) for their contents of atranol and chloroatranol. The 2 substances were found in 87% (n = 27) of the products. The median concentration of atranol in perfumes was 0.502 micro g/ml and 0.012 micro g/ml in eaux de toilette, and 0.235 micro g/ml and 0.006 micro g/ml for chloroatranol, respectively, in perfumes and eaux de toilette. Chloroatranol was found at a maximum concentration of 53 micro g/ml and atranol at one of 190 micro g/ml. The wide exposure to oak moss allergens, together with significant amounts of these potent allergens in at least half of perfumes and some eaux de toilettes explains the high frequencies of oak moss absolute allergy. It is suggested that regulations should be introduced aimed directly at these substances, and not just at oak moss absolute.

Allergens↗
PubMed2006

Microarthropods mediate sperm transfer in mosses.

Among flowering plants, animals commonly act as pollinators. We showed that fertile moss shoots attract springtails and mites, which in turn carry moss sperm, thereby enhancing the fertilization process. Previously, fertilization of mosses was thought to depend on the capacity of individual sperm to swim through a continuous water layer. The role of microarthropods in moss fertilization resembles the role of animals as pollinators of flowering plants but may be evolutionarily much older because of the antiquity of the organism groups involved.

Animals↗
PubMed2006

Influence of overstory removal on growth of epiphytic mosses and lichens in western Oregon.

Will old-growth-associated epiphytes survive if the forest canopy is opened around them by thinning or partial harvest? If old-growth association is due to a species' environmental tolerances, it may not survive in the relatively open stands that result from such treatments. If, however, old-growth association is due to dispersal limitations rather than environmental tolerances, retention of host trees as refugia and sources of inoculum might carry populations of old-growth-associated epiphytes into young stands. We studied growth rates of lichen and moss transplants in a Douglas-fir (Pseudotsuga menziesii) forest (tree ages approximately 55 yr) in western Oregon for nine months before and 27 months after moderate thinning, creation of 0.4-ha patch cuts, and in control areas. We also assessed moss sporophyte production. We contrasted responses of one moss species, Isothecium myosuroides sensu lato, which is ubiquitous in forests of varying ages, with those of another moss, Antitrichia curtipendula, and a lichen, Lobaria oregana, which are both associated with old-growth forests. Both old-growth associates grew faster in thinned areas and patch cuts than in controls, while Isothecuim grew most slowly and produced fewest sporophytes in patch cuts. These species are likely to survive in remnants, assuming they can remain attached, and may be successful in young stands if they can disperse and establish there. Our results suggest that logging with green-tree retention and other silvicultural practices that preserve trees or shrubs hosting the species studied here are likely to encourage these species' development in managed forests.

Bryophyta↗