Notes breus (flora). Saxifraga stolonifera Meerb. (= S. sarmentosa L.) a La Garrotxa Saxifraga stolonifera Meerb. (= S. sarmentosa L.) in La Garrotxa (NE Catalonia)

Nota breu de flora que fa referència a la presència de Saxifraga stolonifera Meerb a La Garrotxa

Notes breus (flora). Addicions i anotacions a la flora vascular de les illes Medes

Nota breu de flora relacionada amb la localització a les Illes Medes, d'una sèrie de tàxons que no figuren en el catàleg florístic de Bolòs & Vigo (1984)

Notes breus (flora). Sicyos angulatus L. al Gironès = Sicyos angulatus L. in Gironès (Catalonia)

Nota breu de flora sobre la presència de Sicyos angulatus L., recollida al llarg del riu Ter, als municipis de Girona,Celrà i Bordils (Gironès, quadrats UTM 31T DG84, DG85 i DG95), entre els 40 i 65 md’altitud

Notes breus (flora). Thymus mastichina L. a la Selva

Nota breu de flora sobre la presència de Thymus mastichina L. en una antiga pedrera de Susqueda, al nord de l'embassament, a tocar de la paret de la presa (3lT DG6048, 440 m)

Síntese do butirato de n-butila empregando lipase microbiana imobilizada em copolímero de estireno-divinilbenzeno

This work investigates the reaction parameters of an immobilized lipase in the esterification reaction of n-butanol and butyric acid. Microbial lipase from Candida rugosa was immobilized onto styrene-divinylbenzene copolymer (STY-DVB) and subsequently introduced in an organic medium containing substrates in appropriate concentrations. Heptane was selected as solvent on the basis of its compatibility with the resin and the enzyme. The influence of molar ratio of acid to alcohol, amount of immobilized lipase and temperature on the butyl butyrate formation was determined. The results were compared with those achieved with free lipase and Lipozyme (commercially immobilized lipase) under the same operational conditions.

Efeito do polietilenoglicol e da albumina na imobilização de lipase microbiana e na catálise em meio orgânico

Poly (ethylene) glycol (PEG) and bovine serum albumin (BSA), as additive agents, were used to enhance the activity of immobilized microbial lipase in organic solvent. Controlled pore silica (CPS) was selected as matrix and different immobilization procedures were evaluated: directly lipase binding on CPS and simultaneous addition of lipase and additive agent on the same support. The highest coupling yield (59.6%) was attained when the immobilization procedure was performed at lipase loading of 150 U/g support in the presence of PEG-1.500. This immobilized system was used in esterification reactions under repeated batch cycles and the biocatalyst half-life was found to increase 2.7 times when compared with the control.

La flora i la vegetació

Descripció de la flora i vegetació de les Gavarres

Corologia de la flora vascular d'interès de conservació al Parc Natural del Montseny

Presentem els resultats dels estudis realitzats des del 2009 al 2012, amb la finalitat de millorar la informació corològica disponibled'espècies de flora vascular considerades d'interès de conservació al Parc Natural del Montseny. S'han tingut en compte un total de 125tàxons. D'aquests, 3 corresponen a tàxons nous per la flora del massís (Aconitum vulparia, Botrychium matricariifolium i Polystichumlonchitis), 7 han estat retrobats i 13 corresponen a novetats per algun dels quadrats UTM 10 × 10 prospectats. Tot i les troballes, moltesespècies no han sigut localitzades durant el treball de camp. En alguns casos, atribuïm aquest fet a la reducció de les poblacions o fins i tota la desaparició, fet que afecta principalment a aquelles espècies vinculades majoritàriament a ambients oberts, que han patit una recessióimportant durant les darreres dècades. Aquest fenomen ha estat especialment rellevant al massís del turó de l'Home, sobretot a la vall deSanta Fe

Produção de isomaltulose, um substituto da sacarose, utilizando glicosiltransferase microbiana

Isomaltulose, a functional isomer of sucrose, is a non-cariogenic reducing disaccharide; has a low glycemic index; selectively promotes growth of beneficial bifidobacteria in the human intestinal microflora; and has greater stability than sucrose in some foods and beverages. Isomaltulose is a nutritional sugar that is digested more slowly than sucrose, and has health advantages for diabetics and nondiabetics. Immobilization techniques, especially entrapment of the cells, are widely used for conversion of sucrose into isomaltulose. Immobilization offers advantages such as minimum downstream processing, continuous operation and reusability of cells. Isomaltulose is currently considered to be a promising sugar substitute.

Avaliação da filtração e ozonização de efluente sanitário primário: aspectos de inativação microbiana e variáveis de ozonização

Ozonation tests with and without prior filtration by means of a 50 micron mesh cartridge filter were conducted with primary sanitary effluents. Filtration led to increased inactivation efficiencies with regard to total and thermotolerant coliforms but it did not seem to influence heterotrophic plate count (HPC) bacteria inactivation efficiencies significantly. Application of the Chick-Watson model to experimental data obtained in the situation of constant inactivation showed that the ozone dosage was more important to bacterial inactivation than the contact time with regard to the cases of thermotolerant coliform inactivation in filtered samples and HPC bacteria and total coliform inactivation in non-filtered samples.

Effects of landscape evolution on flora and habitats in agricultural mosaics

A landscape mosaic is a landscape that consist of various patches, inhabited by different habitat communities over time. Agricultural mosaics area result of the long history between societies and the environment. The understanding of the driving forces for change in this landscapes, and their effect on biodiversity, allow the development of useful tools to assess and manage natural heritage. Plant diversity, endangered plant species and interesting habitats receive the center of attention, because of their capability to integrate and reflect the main changes of this landscapes after medium and long-term.

Flora Fennica

Invocatio: D.D.

Desempenho da matriz híbrida SiO2-quitosana na imobilização da lipase microbiana de Candida rugosa

Lipase from Candida rugosa was immobilized by covalent attachment on hybrid SiO2-chitosan obtained by sol-gel technique. A comparative study between free and immobilized lipase was provided in terms of pH, temperature, kinetic parameters and thermal stability on the olive oil hydrolysis. The pH and temperature for maximum activity shifted from 7.0 and 45 ºC for the free lipase to 7.5 and wide range of temperature (40-50 ºC) after immobilization. Kinetics parameters were found to obey Michaelis-Menten equation and K M values indicated that immobilization process reduced the affinity of enzyme-substrate; however Kd values revealed an increase of thermal stability of lipase.