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1

Molecular analysis of Broussonetia papyrifera (L.) Vent. (Magnoliophyta: Urticales) from the Pacific, based on ribosomal sequences of nuclear DNA  

Microsoft Academic Search

Broussonetia papyrifera (L.) Vent. (Magnoliophyta: Urticales), or paper mulberry, is a species of Asian origin dispersed by humans throughout the Pacific. Our aim is to evaluate the genetic variability of this plant in order to determine its potential as a commensal species for studying the mobility and\\/or migratory movements of the people that carried it. For this study, we analysed

D Seelenfreund; R Piña; K-Y Ho; S Lobos; Ximena Moncada; A Seelenfreund

2011-01-01

2

Antiproliferative activity of essential oils derived from plants belonging to the Magnoliophyta division.  

PubMed

The essential oils obtained from different officinal plants of Lebanon, belonging to the Magnoliophyta division, have been tested for their antiproliferative activity on human erythroleukemic K562 cells. Satureja montana showed the most interesting biological activity in inhibiting the cell growth and inducing erythroid differentiation of K562 cells. The essential oil of Satureja montana was therefore analyzed using a GC/MS (gas chromatography/mass spectrometry) system in order to identify the major constituents and compare them with analysis performed on Satureja hortensis. We demonstrated that the essential oil composition varied with the species, the major constituent of Satureja hortensis being carvacrol (50.61%) and that of Satureja montana being alpha-terpineol (12.66%). In order to identify molecules possibly responsible for the biological activity, commercially available derivatives have been assayed on the K562 cell line. Satureja montana essential oil displayed different natural derivatives characterized by higher activity than those present in Satureja hortensis. The common active principles are alpha-pinene, gamma-terpinene, 4-terpineol, alpha-terpineol, tau-cadinene, tau-cadinol and caryophyllene. Both caryophyllene and alpha-terpineol showed important antiproliferative effects on K562 cells. PMID:16964395

Lampronti, Ilaria; Saab, Antoine M; Gambari, Roberto

2006-10-01

3

On some specifi cities of seed formation in Salvia nemorosa (Lamiaceae)  

Microsoft Academic Search

Th e embryological processes leading to seed formation in S. nemorosa are comprehensively studied for the fi rst time. A number of embryological specifi cities have been established, typical of the malesterile plants. Th ey show that the investigated species manifests a tendency for transition from hermaphrodite to the evolutionally more advanced unisexual fl owers in Magnoliophyta.

Tzvetana Daskalova

4

Structural carbohydrates in a plant biomass: correlations between the detergent fiber and dietary fiber methods.  

PubMed

We compared the detergent fiber and dietary fiber methods to analyze the cellulose and hemicellulose contents of commelinid and non-commelinid magnoliophyta biomass. A good linear correlation was found between both methods. Compared to the more accurate dietary fiber method, the detergent fiber method overestimates the content of cellulose, whereas the detergent fiber method, as compared to the dietary fiber method, overestimates and underestimates the hemicellulose content in commelinid and non-commelinid magnoliophyta biomass, respectively. Because of the good linear correlations, conversion factors were determined to predict the cellulose, hemicellulose, and xylan contents to be expected from the dietary fiber method, on the basis of analyses made by the faster, cheaper, and more commonly practiced detergent fiber method. Nevertheless, the dietary fiber method offers the advantage of providing the detailed composition of the hemicelluloses (xylan, arabinan, hemicellulosic glucan, galactan, and mannan), and that is of interest for biorefining purposes. PMID:24841506

Godin, Bruno; Agneessens, Richard; Gerin, Patrick; Delcarte, Jérôme

2014-06-18

5

Biodiversity patterns of macrophyte and macroinvertebrate communities in two lagoons of Western Greece.  

NASA Astrophysics Data System (ADS)

Aquatic macrophytes and benthic macroinvertebrates were studied seasonally (Spring, Autumn, Summer) between the years 2009 - 2011 in two coastal lagoons (Kotychi and Prokopos) located in Peloponnese, Greece, in order to investigate spatial and temporal biodiversity trends related to hydrological processes (degree of confinement, nitrates, phosphates, chl-a, total suspended materials, light irradiance, pH, salinity, temperature and dissolved oxygen). Kotychi lagoon presents a better communication with the sea, while Prokopos has a high degree of confinement. Both ecosystems seasonally receive freshwater input from streams. The submerged aquatic macrophytes constituted a major component of the ecosystems studied. In total, 22 taxa of aquatic macrophytes (angiosperms and macroalgae), 16 taxa for Kotychi (2 Rhodophyta, 8 Chlorophyta, 5 Magnoliophyta, 1 Streptophyta) and 14 taxa for Prokopos (1 Rhodophyta, 5 Chlorophyta, 5 Magnoliophyta, 3 Streptophyta) were found. Ruppia cirrhosa, and Potamogeton pectinatus were dominant in both lagoons. Kotychi lagoon was also dominated by Zostera noltii and Prokopos by Zannichellia pallustris ssp. pedicellata, while the biomass of aquatic species peaked during the summer periods, in both lagoons. The total number of macroinvertebrates found in the lagoons was 28 taxa for Kotychi and 19 for Prokopos. Chironomidae were dominant in both lagoons, while Kotychi was also dominated by Lekanesphaera monodi and Monocorophium insidiosum, and Prokopos by Ostracoda and Lekanesphaera monodi. Benthic diversity ranged from 1.33 to 2.57 in Kotychi and from 0.67 to 2.48 in Prokopos. Species richness, diversity, and abundance of benthic macroinvertebrates were strongly related to aquatic vegetation and to the degree of communication with the marine environment. Moreover, species richness and abundance of both macrophytes and macroinvertebrates were mainly dependent on depth, temperature, pH and concentration of total suspended materials (TSM). Results also showed that environmental variables such as depth, transparency/depth ratio, total P, chl-a, and TSM differed significantly between the two lagoons. In order to assess the ecological quality of the study sites, the functional ISD index has been applied. From the preliminary results it seems that ISD index, based on the biomass size structure of the macroinvertebrate communities, is more appropriate for the assessment of the ecological status for these particular ecosystems. The development of a monitoring team is essential for the protection and management of these ecologically important ecosystems. Further investigation is necessary to examine the relationships between benthic macroinvertebrates and aquatic macrophytes, the use of biotic indices to the evaluation for lagoonal ecosystems' ecological status and the relation between the hydrological processes and the biodiversity patterns of the biotic elements.

Fyttis, G.; Reizopoulou, S.; Papastergiadou, E.

2012-04-01

6

In Vitro Screening of Tumoricidal Properties of International Medicinal Herbs: Part II  

PubMed Central

With growing use of anticancer complementary and alternative medicines (CAMs) worldwide, there is a need to assess and screen commercially available natural products for relative tumoricidal properties under standard experimental conditions. In the current study, we screened and ranked 264 traditional Chinese and Egyptian herbal medicines for tumoricidal potency against malignant neuroblastoma in vitro. The data obtained show that tumoricidal potencies of plants were randomly dispersed throughout similar orders, families and genera under the Division: Magnoliophyta, class: Magnoliopsida, subclasses: Asteridae, Caryophyllidae, Dilleniidae, Hamamelididae, Magnoliidae and Rosidae. The most potent plant extracts (LC50 < 0.08 mg/ml) were prepared from gromwell root also known as ‘Hong Tiao Zi Cao’ (Lithospermum Erythrorhizon) Family (Boraginaceae) > beth root (Trillium Pendulum), Family (Liliaceae) and galbanum (Ferula Galbaniflua), Family (Apiaceae). Gromwell root is traditionally used in the preparation of Chinese medicinal tea. In addition, galbanum was highly regarded for its sacred and medicinal value according to ancient texts and the bible. Future research will be required to isolate and identify chemical constituents within these plants which are responsible for tumoricidal effects. PMID:20564497

Mazzio, Elizabeth A.; Soliman, Karam F. A.

2010-01-01

7

Structure of mixed ombrophyllous forests with Araucaria angustifolia (Araucariaceae) under external stress in Southern Brazil.  

PubMed

This study is part of the Floristic and Forest Inventory of Santa Catarina, conceived to evaluate forest resources, species composition and structure of forest remnants, providing information to update forest conservation and land use policy in Southern Brazilian State of Santa Catarina (95 000 km2). In accordance to the Brazilian National Forest Inventory (IFN-BR), the inventory applies systematic sampling, with 440 clusters containing four crosswise 1 000m2 plots (20 x 50m) each, located on a 10 x 10km grid overlaid to land use map based on classification of SPOT-4 images from 2005. Within the sample units, all woody individuals of the main stratum (DBH > or = 10cm) are measured and collected (fertile and sterile), if not undoubtedly identified in field. Regeneration stratum (height > 1.50m; DBH < 10cm) is registered in 100m2 in each sample unit. Floristic sampling includes collection of all fertile trees, shrubs and herbs within the sample unit and in its surroundings. This study performs analysis based on 92 clusters measured in 2008 within an area of 32320km2 of mixed ombrophyllous forests with Araucaria angustifolia located at the state's high plateau (500m to 1 560m above sea level at 26 degrees 00'-28 degrees 30' S and 49 degrees 13'-51 degrees 23' W). Mean density (DBH > or = 10cm) is 578 individuals/ha (ranging from 85/ha to 1 310/ha), mean species richness in measured remnants is 35 (8 to 62), Shannon and Wiener diversity index (H') varies between 1.05 and 3.48. Despite high total species diversity (364 Magnoliophyta, five Coniferophyta and one tree fern) and relatively high mean basal area (25.75m2/ha, varying from 3.87 to 68.85m2/ha), the overwhelming majority of forest fragments are considered highly impacted and impoverished, mostly by logging, burning and extensive cattle farming, turning necessary more efficient protection measures. Basal area was considered an appropriate indicator for stand quality and conservation status. PMID:22017139

Vibrans, Alexander C; Sevegnani, Lúcia; Uhlmann, Alexandre; Schorn, Lauri A; Sobral, Marcos G; de Gasper, André L; Lingner, Débora V; Brogni, Eduardo; Klemz, Guilherme; Godoy, Marcela B; Verdi, Marcio

2011-09-01

8

A general classification of silicon utilizing organisms  

NASA Astrophysics Data System (ADS)

Silicon utilizing organisms may be defined as organisms with high silicon content (? 1% dry weight) and they can metabolize silicon with or without demonstrable silicon transporter genes (SIT) in them(Das,2010). Silicon is the second most abundant element in the lithosphere (27.70%) and it is as important as phosphorus and magnesium (0.03%) in the biota. Hydrated silica represents the second most abundant biogenic mineral after carbonate minerals. Silicon is accumulated and metabolized by some prokaryotes, and Si compounds can stimulate the growth of a range of fungi. It is well known that Si is essential for diatoms. In mammals, Si is considered an essential trace element, required in bone, cartilage and connective tissue formation, enzymatic activities and other metabolic processes. Silicon was suggested to act as a phosphoprotein effector in bone. In mammals, Si is also reported to positively influence the immune system and to be required for lymphocyte proliferation. The aqueous chemistry of Si is dominated by silicic acid at biological pH ranges. Monosilicic acid can form stable complexes with organic hydroxy-containing molecules . Biosilica also has been identified associated with various biomolecules including proteins and carbohydrates. There are main seven groups of silicon utilizing organisms belonging to Gram positive bacteria, algae, protozoa, sponges, fungi, lichens, and monocotyledon plants. In each group again all the members are not silicon utilizing organisms, thus selective members in each group are further classified depending their degree of silicon utilization. Important silicon utilizing bacteria are Mycobacteria, Nocardia, Streptomyces, Staphylococcus, Bacillus, Lactobacillus spp. etc., Important silicon utilizing algae are Centrobacillariophyceae, Pennatibacillariophyceae and Chrysophyceae. Many protozoa belonging to Heterokonta, Choanoflagellida, Actinopoda are well known silicon utilizing microorganisms. Hexactinellida ( glass sponges), Demospongiae and Sclerospongiae are important silicon utilizing sponges. Fungi like Aspergillus, Penicillium, Rhizopus etc. are also silicon utilizing. Candida spp. also belong to silicon utilizing organisms as they are also frequently found in sputum in silicotuberculosis cases. Many monocotyledon plants belonging to Pteridophyta, Magnoliophyta etc. are also well known silicon utilizing organisms. Almost all lichens belong to the group of silicon utilizing organisms.

Das, P.; Das, S.

2010-12-01