Staff Publications

Staff Publications

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    'Staff publications' is the digital repository of Wageningen University & Research

    'Staff publications' contains references to publications authored by Wageningen University staff from 1976 onward.

    Publications authored by the staff of the Research Institutes are available from 1995 onwards.

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Rarity of monodominance in hyperdiverse Amazonian forests
Steege, Hans Ter; Henkel, Terry W. ; Helal, Nora ; Marimon, Beatriz S. ; Marimon-Junior, Ben Hur ; Huth, Andreas ; Groeneveld, Jürgen ; Sabatier, Daniel ; Souza Coelho, Luiz de; Andrade Lima Filho, Diogenes de; Salomão, Rafael P. ; Amaral, Iêda Leão ; Almeida Matos, Francisca Dionízia de; Castilho, Carolina V. ; Phillips, Oliver L. ; Guevara, Juan Ernesto ; Jesus Veiga Carim, Marcelo de; Cárdenas López, Dairon ; Magnusson, William E. ; Wittmann, Florian ; Irume, Mariana Victória ; Martins, Maria Pires ; Silva Guimarães, José Renan da; Molino, Jean François ; Bánki, Olaf S. ; Piedade, Maria Teresa Fernandez ; Pitman, Nigel C.A. ; Mendoza, Abel Monteagudo ; Ramos, José Ferreira ; Luize, Bruno Garcia ; Moraes de Leão Novo, Evlyn Márcia ; Núñez Vargas, Percy ; Silva, Thiago Sanna Freire ; Venticinque, Eduardo Martins ; Manzatto, Angelo Gilberto ; Reis, Neidiane Farias Costa ; Terborgh, John ; Casula, Katia Regina ; Honorio Coronado, Euridice N. ; Montero, Juan Carlos ; Feldpausch, Ted R. ; Duque, Alvaro ; Costa, Flávia R.C. ; Arboleda, Nicolás Castaño ; Schöngart, Jochen ; Killeen, Timothy J. ; Vasquez, Rodolfo ; Mostacedo, Bonifacio ; Demarchi, Layon O. ; Assis, Rafael L. ; Baraloto, Chris ; Engel, Julien ; Petronelli, Pascal ; Castellanos, Hernán ; Medeiros, Marcelo Brilhante de; Quaresma, Adriano ; Simon, Marcelo Fragomeni ; Andrade, Ana ; Camargo, José Luís ; Laurance, Susan G.W. ; Laurance, William F. ; Rincón, Lorena M. ; Schietti, Juliana ; Sousa, Thaiane R. ; Sousa Farias, Emanuelle de; Lopes, Maria Aparecida ; Magalhães, José Leonardo Lima ; Mendonça Nascimento, Henrique Eduardo ; Lima de Queiroz, Helder ; Aymard C, Gerardo A. ; Brienen, Roel ; Revilla, Juan David Cardenas ; Vieira, Ima Célia Guimarães ; Cintra, Bruno Barçante Ladvocat ; Stevenson, Pablo R. ; Feitosa, Yuri Oliveira ; Duivenvoorden, Joost F. ; Mogollón, Hugo F. ; Araujo-Murakami, Alejandro ; Ferreira, Leandro Valle ; Lozada, José Rafael ; Comiskey, James A. ; Toledo, José Julio de; Damasco, Gabriel ; Dávila, Nállarett ; Draper, Freddie ; García-Villacorta, Roosevelt ; Lopes, Aline ; Vicentini, Alberto ; Alonso, Alfonso ; Dallmeier, Francisco ; Gomes, Vitor H.F. ; Lloyd, Jon ; Neill, David ; Aguiar, Daniel Praia Portela de; Arroyo, Luzmila ; Carvalho, Fernanda Antunes ; Souza, Fernanda Coelho de; Amaral, Dário Dantas do; Feeley, Kenneth J. ; Gribel, Rogerio ; Pansonato, Marcelo Petratti ; Barlow, Jos ; Berenguer, Erika ; Ferreira, Joice ; Fine, Paul V.A. ; Guedes, Marcelino Carneiro ; Jimenez, Eliana M. ; Licona, Juan Carlos ; Peñuela Mora, Maria Cristina ; Villa, Boris ; Cerón, Carlos ; Maas, Paul ; Silveira, Marcos ; Stropp, Juliana ; Thomas, Raquel ; Baker, Tim R. ; Daly, Doug ; Dexter, Kyle G. ; Huamantupa-Chuquimaco, Isau ; Milliken, William ; Pennington, Toby ; Ríos Paredes, Marcos ; Fuentes, Alfredo ; Klitgaard, Bente ; Pena, José Luis Marcelo ; Peres, Carlos A. ; Silman, Miles R. ; Tello, J.S. ; Chave, Jerome ; Cornejo Valverde, Fernando ; Fiore, Anthony Di; Hilário, Renato Richard ; Phillips, Juan Fernando ; Rivas-Torres, Gonzalo ; Andel, Tinde R. van; Hildebrand, Patricio von; Noronha, Janaína Costa ; Barbosa, Edelcilio Marques ; Barbosa, Flávia Rodrigues ; Matos Bonates, Luiz Carlos de; Sá Carpanedo, Rainiellen de; Dávila Doza, Hilda Paulette ; Fonty, Émile ; GómeZárate Z, Ricardo ; Gonzales, Therany ; Gallardo Gonzales, George Pepe ; Hoffman, Bruce ; Junqueira, André Braga ; Malhi, Yadvinder ; Andrade Miranda, Ires Paula de; Pinto, Linder Felipe Mozombite ; Prieto, Adriana ; Jesus Rodrigues, Domingos de; Rudas, Agustín ; Ruschel, Ademir R. ; Silva, Natalino ; Vela, César I.A. ; Vos, Vincent Antoine ; Zent, Egleé L. ; Zent, Stanford ; Weiss Albuquerque, Bianca ; Cano, Angela ; Carrero Márquez, Yrma Andreina ; Correa, Diego F. ; Costa, Janaina Barbosa Pedrosa ; Flores, Bernardo Monteiro ; Galbraith, David ; Holmgren, Milena ; Kalamandeen, Michelle ; Nascimento, Marcelo Trindade ; Oliveira, Alexandre A. ; Ramirez-Angulo, Hirma ; Rocha, Maira ; Scudeller, Veridiana Vizoni ; Sierra, Rodrigo ; Tirado, Milton ; Umaña Medina, Maria Natalia ; Heijden, Geertje van der; Vilanova Torre, Emilio ; Vriesendorp, Corine ; Wang, Ophelia ; Young, Kenneth R. ; Ahuite Reategui, Manuel Augusto ; Baider, Cláudia ; Balslev, Henrik ; Cárdenas, Sasha ; Casas, Luisa Fernanda ; Farfan-Rios, William ; Ferreira, Cid ; Linares-Palomino, Reynaldo ; Mendoza, Casimiro ; Mesones, Italo ; Torres-Lezama, Armando ; Giraldo, Ligia Estela Urrego ; Villarroel, Daniel ; Zagt, Roderick ; Alexiades, Miguel N. ; Oliveira, Edmar Almeida de; Garcia-Cabrera, Karina ; Hernandez, Lionel ; Palacios Cuenca, Walter ; Pansini, Susamar ; Pauletto, Daniela ; Ramirez Arevalo, Freddy ; Sampaio, Adeilza Felipe ; Valderrama Sandoval, Elvis H. ; Valenzuela Gamarra, Luis ; Levesley, Aurora ; Pickavance, Georgia ; Melgaço, Karina - \ 2019
Scientific Reports 9 (2019). - ISSN 2045-2322

Tropical forests are known for their high diversity. Yet, forest patches do occur in the tropics where a single tree species is dominant. Such "monodominant" forests are known from all of the main tropical regions. For Amazonia, we sampled the occurrence of monodominance in a massive, basin-wide database of forest-inventory plots from the Amazon Tree Diversity Network (ATDN). Utilizing a simple defining metric of at least half of the trees ≥ 10 cm diameter belonging to one species, we found only a few occurrences of monodominance in Amazonia, and the phenomenon was not significantly linked to previously hypothesized life history traits such wood density, seed mass, ectomycorrhizal associations, or Rhizobium nodulation. In our analysis, coppicing (the formation of sprouts at the base of the tree or on roots) was the only trait significantly linked to monodominance. While at specific locales coppicing or ectomycorrhizal associations may confer a considerable advantage to a tree species and lead to its monodominance, very few species have these traits. Mining of the ATDN dataset suggests that monodominance is quite rare in Amazonia, and may be linked primarily to edaphic factors.

Can timber provision from Amazonian production forests be sustainable?
Piponiot, Camille ; Rödig, Edna ; Putz, Francis E. ; Rutishauser, Ervan ; Sist, Plinio ; Ascarrunz, Nataly ; Blanc, Lilian ; Derroire, Géraldine ; Descroix, Laurent ; Guedes, Marcelino Carneiro ; Coronado, Euridice Honorio ; Huth, Andreas ; Kanashiro, Milton ; Licona, Juan Carlos ; Mazzei, Lucas ; Oliveira, Marcus Vinicio Neves D'; Peña-Claros, Marielos ; Rodney, Ken ; Shenkin, Alexander ; Souza, Cintia Rodrigues De; Vidal, Edson ; West, Thales A.P. ; Wortel, Verginia ; Hérault, Bruno - \ 2019
Environmental Research Letters 14 (2019)6. - ISSN 1748-9318
Amazonia - disturbance - ecosystem recovery - macroecology - Selective logging - tropical forestry

Around 30 Mm3 of sawlogs are extracted annually by selective logging of natural production forests in Amazonia, Earth's most extensive tropical forest. Decisions concerning the management of these production forests will be of major importance for Amazonian forests' fate. To date, no regional assessment of selective logging sustainability supports decision-making. Based on data from 3500 ha of forest inventory plots, our modelling results show that the average periodic harvests of 20 m3 ha-1 will not recover by the end of a standard 30 year cutting cycle. Timber recovery within a cutting cycle is enhanced by commercial acceptance of more species and with the adoption of longer cutting cycles and lower logging intensities. Recovery rates are faster in Western Amazonia than on the Guiana Shield. Our simulations suggest that regardless of cutting cycle duration and logging intensities, selectively logged forests are unlikely to meet timber demands over the long term as timber stocks are predicted to steadily decline. There is thus an urgent need to develop an integrated forest resource management policy that combines active management of production forests with the restoration of degraded and secondary forests for timber production. Without better management, reduced timber harvests and continued timber production declines are unavoidable.

Intraspecific variability in response to phosphorus depleted conditions in the cyanobacteria Microcystis aeruginosa and Raphidiopsis raciborskii
Guedes, Iame Alves ; Pacheco, Ana Beatriz F. ; Vilar, Mauro C.P. ; Mello, Mariana M. ; Marinho, Marcelo Manzi ; Lurling, Miquel ; Azevedo, Sandra M.F.O. - \ 2019
Harmful Algae 86 (2019). - ISSN 1568-9883 - p. 96 - 105.
Cylindrospermopsis - Ecotypes - Phosphorus uptake - Strain variability

Phosphorus loading plays an important role in the occurrence of cyanobacterial blooms and understanding how this nutrient affects the physiology of cyanobacteria is imperative to manage these phenomena. Microcystis aeruginosa and Raphidiopsis raciborskii are cyanobacterial species that form potentially toxic blooms in freshwater ecosystems worldwide. Blooms comprise numerous strains with high trait variability, which can contribute to the widespread distribution of these species. Here, we explored the intraspecific variability in response to phosphorus depleted conditions (P-)testing five strains of each species. Strains could be differentiated by cell volume or genetic profiles except for those of the same species, sampling location and date, though these presented differences in their response to (P-). Although differently affected by (P-)over 10 days, all strains were able to grow and maintain photosynthetic activity. For most M. aeruginosa and R. raciborskii strains growth rates were not significantly different comparing (P+)and (P-)conditions. After ten days in (P-), only one M. aeruginosa strain and two R. raciborskii strains showed reduction in biovolume yield as compared to (P+)but in most strains chlorophyll-a concentrations were lower in (P-)than in (P+). Reduced photosystem II efficiency was found for only one R. raciborskii strain while all M. aeruginosa strains were affected. Only two M. aeruginosa and one R. raciborskii strain increased alkaline phosphatase activity under (P-)as compared to (P+). Variation in P-uptake was also observed but comparison among strains yielded homogeneous groups comprised of representatives of both species. Comparing the response of each species as a whole, the (P-)condition affected growth rate, biovolume yield and chlorophyll yield. However, these parameters revealed variation among strains of the same species to the extent that differences between M. aeruginosa and R. raciborskii were not significant. Taken together, these results do not support the idea that R. raciborskii, as a species, can withstand phosphorus limitation better than M. aeruginosa and also point that the level of intraspecific variation may preclude generalizations based on studies that use only one or few strains.

Inhibition Studies with 2-Bromoethanesulfonate Reveal a Novel Syntrophic Relationship in Anaerobic Oleate Degradation
Salvador, A.F. ; Cavaleiro, A.J. ; Paulo, A.M.S. ; Silva, S.A. ; Guedes, A.P. ; Pereira, M.A. ; Stams, A.J.M. ; Sousa, D.Z. ; Alves, M.M. - \ 2019
Applied and Environmental Microbiology 85 (2019)2. - ISSN 0099-2240
2-bromoethanesulfonate (BrES) - desulfonation - Desulfovibrio - isethionate - oleate - Syntrophomonas - syntrophy

Degradation of long-chain fatty acids (LCFAs) in methanogenic environments is a syntrophic process involving the activity of LCFA-degrading bacteria and hydrogen-utilizing methanogens. If methanogens are inhibited, other hydrogen scavengers are needed to achieve complete LCFA degradation. In this work, we developed two different oleate (C18:1 LCFA)-degrading anaerobic enrichment cultures, one methanogenic (ME) and another in which methanogenesis was inhibited (IE). Inhibition of methanogens was attained by adding a solution of 2-bromoethanesulfonate (BrES), which turned out to consist of a mixture of BrES and isethionate. Approximately 5 times faster oleate degradation was accomplished by the IE culture compared with the ME culture. A bacterium closely related to Syntrophomonas zehnderi (99% 16S rRNA gene identity) was the main oleate degrader in both enrichments, in syntrophic relationship with hydrogenotrophic methanogens from the genera Methanobacterium and Methanoculleus (in ME culture) or with a bacterium closely related to Desulfovibrio aminophilus (in IE culture). A Desulfovibrio species was isolated, and its ability to utilize hydrogen was confirmed. This bacterium converted isethionate to acetate and sulfide, with or without hydrogen as electron donor. This bacterium also utilized BrES but only after 3 months of incubation. Our study shows that syntrophic oleate degradation can be coupled to desulfonation.IMPORTANCE In anaerobic treatment of complex wastewater containing fat, oils, and grease, high long-chain fatty acid (LCFA) concentrations may inhibit microbial communities, particularly those of methanogens. Here, we investigated if anaerobic degradation of LCFAs can proceed when methanogens are inhibited and in the absence of typical external electron acceptors, such as nitrate, iron, or sulfate. Inhibition studies were performed with the methanogenic inhibitor 2-bromoethanesulfonate (BrES). We noticed that, after autoclaving, BrES underwent partial hydrolysis and turned out to be a mixture of two sulfonates (BrES and isethionate). We found out that LCFA conversion proceeded faster in the assays where methanogenesis was inhibited, and that it was dependent on the utilization of isethionate. In this study, we report LCFA degradation coupled to desulfonation. Our results also showed that BrES can be utilized by anaerobic bacteria.

Chitosan as coagulant on cyanobacteria in lake restoration management may cause rapid cell lysis
Nunes Teixeira Mucci, Maira ; Noyma, Natalia Pessoa ; Magalhães, Leonardo de; Miranda, Marcela ; Oosterhout, Frank van; Guedes, Iamê Alves ; Huszar, Vera L.M. ; Marinho, Marcelo Manzi ; Lürling, Miquel - \ 2017
Water Research 118 (2017). - ISSN 0043-1354 - p. 121 - 130.
Cell lysis - Cell viability - Cyanobacterial blooms - Eutrophication - Lake restoration - Photosystem II efficiency

Combining coagulant and ballast to remove cyanobacteria from the water column is a promising restoration technique to mitigate cyanobacterial nuisance in surface waters. The organic, biodegradable polymer chitosan has been promoted as a coagulant and is viewed as non-toxic. In this study, we show that chitosan may rapidly compromise membrane integrity and kill certain cyanobacteria leading to release of cell contents in the water. A strain of Cylindrospermopsis raciborskii and one strain of Planktothrix agardhii were most sensitive. A 1.3 h exposure to a low dose of 0.5 mg l−1 chitosan already almost completely killed these cultures resulting in release of cell contents. After 24 h, reductions in PSII efficiencies of all cyanobacteria tested were observed. EC50 values varied from around 0.5 mg l−1 chitosan for the two sensitive strains, via about 5 mg l−1 chitosan for an Aphanizomenon flos-aquae strain, a toxic P. agardhii strain and two Anabaena cylindrica cultures, to more than 8 mg l−1 chitosan for a Microcystis aeruginosa strain and another A. flos-aquae strain. Differences in sensitivity to chitosan might be related to polymeric substances that surround cyanobacteria. Rapid lysis of toxic strains is likely and when chitosan flocking and sinking of cyanobacteria is considered in lake restoration, flocculation efficacy studies should be complemented with investigation on the effects of chitosan on the cyanobacteria assemblage being targeted.

Conversion of Cn-unsaturated into Cn-2-saturated LCFA can occur uncoupled from methanogenesis in anaerobic bioreactors
Cavaleiro, A.J. ; Pereira, M.A. ; Guedes, A.P. ; Stams, A.J.M. ; Alves, M.M. ; Machado de Sousa, D.Z. - \ 2016
Environmental Science and Technology 50 (2016)6. - ISSN 0013-936X - p. 3082 - 3090.
Fat, oils and grease present in complex wastewater can be readily converted to methane, but the energy potential of these compounds is not always recyclable, due to incomplete degradation of long chain fatty acids (LCFA) released during lipids hydrolysis. Oleate (C18:1) is generally the dominant LCFA in lipid-containing wastewater, and its conversion in anaerobic bioreactors results in palmitate (C16:0) accumulation. The reason why oleate is continuously converted to palmitate without further degradation via β-oxidation is still unknown. In this work, the influence of methanogenic activity in the initial conversion steps of unsaturated LCFA was studied in ten bioreactors continuously operated with saturated or unsaturated C16- and C18-LCFA, in the presence or absence of the methanogenic inhibitor bromoethanesulfonate (BrES). Saturated Cn-2-LCFA accumulated both in the presence and absence of BrES during the degradation of unsaturated Cn-LCFA, and represented more than 50% of total LCFA. In the presence of BrES further conversion of saturated intermediates did not proceed, not even when prolonged batch incubation was applied. As the initial steps of unsaturated LCFA degradation proceed uncoupled from methanogenesis, accumulation of saturated LCFA can be expected. Analysis of the active microbial communities suggests a role for facultative anaerobic bacteria in the initial steps of unsaturated LCFA biodegradation. Understanding this role is now imperative to optimize methane production from LCFA.
Anaerobic co-digestion of cork based oil sorbent and cow manure or sludge
Cavaleiro, A.J. ; Neves, T.M. ; Guedes, A.P. ; Alves, M.M. ; Pinto, P. ; Silva, S.P. ; Machado de Sousa, Diana - \ 2015
In: Wastes: Solutions, Treatments and Opportunities - Selected Papers from the 3rd Edition of the International Conference on Wastes: Solutions, Treatments and Opportunities, 2015. - CRC Press/Balkema - ISBN 9781138028821 - p. 43 - 48.

Cork, a material with great economic, social and environmental importance in Portugal, is also a good oil sorbent that can be used in the remediation of oil spills. The oil-impregnated cork can be easily removed, but requires further treatment. In the case of vegetable oil spills, anaerobic digestion may be a potential solution. This study aims to evaluate the effect of adding cork contaminated with sunflower oil as co-substrate in anaerobic digestion processes. Biodegradability assays were prepared with cow manure or sludge from a wastewater treatment plant, in the presence of five concentrations of oil-contaminated cork, between 200 and 1000 mg · L−1 as COD. Maxi-mum cumulative methane production increased with the amount of oily cork up to 41% and 101% in the assays with manure and sludge, respectively. Sporadic addition of cork contaminated with vegetable oil during anaerobic digestion of manure or sludge increases significantly the methane production of these processes.

Agrobacterium tumefaciens-mediated transformation of Lasiodiplodia theobromae, the causal agent of gummosis in cashew nut plants
Muniz, C.R. ; Silva, C.F. da; Souza, M.T. ; Freire, F.C.O. ; Kema, G.H.J. ; Guedes, M.I.F. - \ 2014
Genetics and Molecular Research 13 (2014)2. - ISSN 1676-5680 - p. 2906 - 2913.
filamentous fungi - genetic-transformation - proteins - tool
Lasiodiplodia theobromae is a major pathogen of many different crop cultures, including cashew nut plants. This paper describes an efficient Agrobacterium tumefaciens-mediated transformation (ATMT) system for the successful delivery of T-DNA, transferring the genes of green fluorescent protein (gfp) and hygromycin B phosphotransferase (hph) to L. theobromae. When the fungal pycnidiospores were co-cultured with A. tumefaciens harboring the binary vector with hph-gfp gene, hygromycin-resistant fungus only developed with acetosyringone supplementation. The cashew plants inoculated with the fungus expressing GFP revealed characteristic pathogen colonization by epifluorescence microscopy. Intense and bright green hyphae were observed for transformants in all extensions of mycelium cultures. The penetration of parenchyma cells near to the inoculation site, beneath the epicuticle surface, was observed prior to 25 dpi. Penetration was followed by the development of hyphae within invaded host cells. These findings provide a rapid and reproducible ATMT method for L. theobromae transformation.
Monitoring cashew seedlings during interactions with the fungus Lasiodiplodia theobromae using chlorophyll fluorescence imaging
Muniz, C.R. ; Freire, F.C.O. ; Viana, F.M.P. ; Cardoso, J.E. ; Sousa, C.A.F. ; Guedes, M.I.F. ; Schoor, R. van der; Jalink, H. - \ 2014
Photosynthetica 52 (2014)4. - ISSN 0300-3604 - p. 529 - 537.
plant-pathogen interactions - a fluorescence - photosynthetic responses - leaves - identification - parameters - infection - regions - stress
The chlorophyll (Chl) fluorescence imaging technique was applied to cashew seedlings inoculated with the fungus Lasiodiplodia theobromae to assess any disturbances in the photosynthetic apparatus of the plants before the onset of visual symptoms. Two-month-old cashew plants were inoculated with mycelium of L. theobromae isolate Lt19 or Lt32. Dark-adapted and light-acclimated whole plants or previously labelled, single, mature leaf from each plant were evaluated weekly for Chl fluorescence parameters. From 21 to 28 days, inoculation with both isolates resulted in the significantly lower maximal photochemical quantum yield of PSII (Fv/Fm) than those for control samples, decreasing from values of 0.78 to 0.62. In contrast, the time response of the measured fluorescence transient curve from dark-acclimated plants increased in both whole plants and single mature leaves in inoculated plants compared with controls. The Fv/Fm images clearly exhibited photosynthetic perturbations 14 days after inoculation before any visual symptoms appeared. Additionally, decays in the effective quantum yield of PSII photochemistry and photochemical quenching coefficient were also observed over time. However, nonphotochemical quenching increased during the evaluation period. We conclude that Fv/Fm images are the effective way of detecting early metabolic perturbations in the photosynthetic apparatus of cashew seedlings caused by gummosis in both whole plants and single leaves and could be potentially employed in larger-scale screening systems.
Evaluation of the nutritive value of muiumba (Baikiaea plurijuga) seeds: chemical composition, in vitro organic matter digestibility and in vitro gas production
Rodrigues, M.A.M. ; Lourenço, A.L. ; Cone, J.W. ; Nunes, F.M. ; Santos, A.S. ; Cordeiro, J.M.M. ; Guedes, C.M.V. ; Ferreira, L.M.M. - \ 2014
SpringerPlus 3 (2014). - ISSN 2193-1801
nonstarch polysaccharides - production profiles - plant materials - dietary fiber - tree fodder - fermentation - feed - fractions - leaves - fruits
One of the main constraints hindering the increase of animal production in semi-arid regions of Africa is the inadequate supply of nutrients during the dry season. Incorporation of alternative feed resources in ruminant diets during this period could be a viable approach to overcome these limitations. The objective of this study was to evaluate the nutritive value of muiumba (Baikiaea plurijuga) tree seeds as an alternative nutrient source for ruminants. Muiumba seeds were compared to other eight feedstuffs including two cereal grains (corn and oat), two wheat by-products (wheat bran and distilled wheat) and four protein meals (coconut meal, sunflower meal, soybean meal and rapeseed meal) as to its chemical composition, in vitro organic matter digestibility (IVOMD) and in vitro gas production. The moderate crude protein concentrations (145 g/kg DM) of muiumba seeds indicate that this feedstuff could not be used as a protein supplement, contrarily to the majority of multipurpose tree seeds. Although the starch content was scarce (15 g/kg DM), the low neutral detergent fibre (235 g/kg DM), low molecular weight sugar (76.1 g/kg DM) and non-starch polysaccharide (510.5 g/kg DM) contents indicate that this feedstuff has potential feeding value. This was confirmed by the IVOMD (0.770) and by the data provided by the in vitro gas production showing that muiumba seeds had high (P <0.05) maximum gas production and fractional fermentation rates, suggesting that these seeds are characterized by a highly fermentable fraction.
Activity and viability of methanogens in anaerobic digestion of unsaturated and saturated long-chain fatty acids
Sousa, D.Z. ; Salvador, A.F. ; Ramos, J. ; Guedes, A.P. ; Barbosa, S. ; Stams, A.J.M. ; Alves, M.M. ; Pereira, M.A. - \ 2013
Applied and Environmental Microbiology 79 (2013)14. - ISSN 0099-2240 - p. 4239 - 4245.
16s ribosomal-rna - microbial communities - calcium addition - waste-water - oleic-acid - bacteria - inhibition - sludge - bioreactors - diversity
Lipids can be anaerobically digested to methane, but methanogens are often considered to be highly sensitive to the long-chain fatty acids (LCFA) deriving from lipids hydrolysis. In this study, the effect of unsaturated (oleate [C18:1]) and saturated (stearate [C18:0] and palmitate [C16:0]) LCFA toward methanogenic archaea was studied in batch enrichments and in pure cultures. Overall, oleate had a more stringent effect on methanogens than saturated LCFA, and the degree of tolerance to LCFA was different among distinct species of methanogens. Methanobacterium formicicum was able to grow in both oleate- and palmitate-degrading enrichments (OM and PM cultures, respectively), whereas Methanospirillum hungatei only survived in a PM culture. The two acetoclastic methanogens tested, Methanosarcina mazei and Methanosaeta concilii, could be detected in both enrichment cultures, with better survival in PM cultures than in OM cultures. Viability tests using live/dead staining further confirmed that exponential growth-phase cultures of M. hungatei are more sensitive to oleate than are M. formicicum cultures; exposure to 0.5 mM oleate damaged 99% ± 1% of the cell membranes of M. hungatei and 53% ± 10% of the cell membranes of M. formicicum. In terms of methanogenic activity, M. hungatei was inhibited for 50% by 0.3, 0.4, and 1 mM oleate, stearate, and palmitate, respectively. M. formicicum was more resilient, since 1 mM oleate and >4 mM stearate or palmitate was needed to cause 50% inhibition on methanogenic activity
Effect of collection time on the fermentative activity of microbes in equine faeces
Desrousseaux, G. ; Santos, A.S. ; Pellikaan, W.F. ; Poel, A.F.B. van der; Cone, J.W. ; Guedes, C.M.V. ; Ferreira, L.M.M. ; Rodrigues, M.A.M. - \ 2012
Animal Feed Science and Technology 178 (2012)3-4. - ISSN 0377-8401 - p. 183 - 189.
in-vitro fermentation - high-starch diet - gas-production - large-intestine - energy content - fecal inocula - high-fiber - horses - rumen - digestibility
The present study intended to evaluate the influence of the collection time of faeces on in vitro fermentation determined with the gas production technique and on the bacteriological counts of the fresh faeces, utilized as inoculum source. Three adult horses, fed hay and concentrates 3 times a day, were used as faeces donors. Fermentation of 5 feedstuffs (barley, oats, alfalfa, meadow hay, and wheat straw), was studied after four collection times: immediately before the morning meal (9:00 h, t0), 2 h after the morning meal (11:00 h, t2), 2 h after the 12:00 h meal (t5) and immediately before the 17:00 h meal (t8). Although there were no differences in pH and bacteriological counts, the proportion in volatile fatty acids, except for acetate, and the extent of fermentation were the highest for t2 (P
Polyclonal Antibody-based ELISA in combination with specific PCR amplification of ITS 1 regions for the detection and quantitation of Lasiodiplodia theobromae, causal agent of 2 gummosis in cashew nut plants
Muniz, C.R. ; Freire, F.C.O. ; Viana, F.M.P. ; Cardoso, J.E. ; Correia, D. ; Jalink, H. ; Kema, G.H.J. ; Silva, G.F. ; Guedes, M.I.F. - \ 2012
Annals of Applied Biology 160 (2012)3. - ISSN 0003-4746 - p. 217 - 224.
south-africa - sp-nov - botryosphaeriaceae - pathogens - endophytes - pinus - stem
Members of Botryosphaeriaceae family are associated with serious diseases in different plants 18 across the world. In cashew nut plants (Anacardium occidentale L.), the fungus Lasiodiplodia 19 theobromae causes a severe group of symptoms related to gummosis that results in decreased nut 20 production. The aim of this work was to develop an indirect enzyme-linked immunosorbent 21 assay (ELISA) with sufficient sensitivity and specificity to detect the fungus both in vitro and in 22 planta (artificially and naturally infected) and to increase the detection specificity within the 23 fungi group using primers specific for the internal transcribed spacer (ITS) sequences. A 24 collection of L. theobromae isolates was obtained, and antisera against the fungus were raised in 25 rabbits. Cross-reactivity against Neofusicoccum sp., Colletotrichum gloeosporioides, Phomopsis 26 anacardii and Pestalotiopsis guepinii was examined. Naturally and artificially infected vegetal 27 material was employed in the ELISAs. The fungi ITS sequences were determined, and single 28 nucleotide polymorphisms were identified and used for primer design. For the naturally infected 29 2 plants, there was an approximately 4-fold variation in the absorbance values. Some positive 1 readings for asymptomatic samples were detected. For the artificially infected samples, an 2 ELISA-based weekly time-course analysis was conducted, and the values for samples from 0 and 3 7 days were lower than the threshold value. Beginning on day 14, the infection could be 4 detected, with rates varying from 40% on day 14 to 80% on day 21 and 100% by the end of the 5 experiment. The ITS sequencing revealed few polymorphisms among the L. theobromae isolates, 6 but for Colletotrichum gloeosporioides, Phomopsis anacardii, Pestalotiopsis guepinii and 7 Neofusicoccum sp., the sequences were sufficient to permit reliable discrimination. The 8 feasibility of ELISA as an early detection technique to assist in gummosis management was 9 demonstrated. PCR amplification based on ITS regions increases and complements serological 10 specificity
The potential of white-rot fungi to degrade phorbol esters of Jatropha curcas L. seed cake
Barros, C.R.M. de; Ferreira, L.M.M. ; Nunes, F.M. ; Bezerra, R.M.F. ; Dias, A.A. ; Guedes, C. ; Cone, J.W. ; Marques, G.S.M. ; Rodrigues, M.A.M. - \ 2011
Engineering in Life Sciences 11 (2011)1. - ISSN 1618-0240 - p. 107 - 110.
chemical-composition - wheat-straw - provenances - diacylglycerols - bioremediation - constituents - mexico - state - water
The potential of solid-state cultivation, with three white-rot fungi (Bjerkandera adusta, Ganoderma resinaceum and Phlebia rufa), to decrease phorbol esters concentration of Jatropha curcas L. was evaluated in this study. Incubation was conducted in 250¿mL Erlenmeyer flasks without agitation at 28°C for 30 days. Phorbol esters were analyzed by reverse-phase HPLC after an extraction procedure using dichloromethane. All fungi studied were able to decrease the concentration of phorbol esters, mainly B. adusta and P. rufa which significantly reduced (p
Modification of wheat straw lignin by solid state fermentation with white-rot fungi
Dinis, M.J. ; Bezerra, R.M.F. ; Nunes, F. ; Dias, A.A. ; Guedes, C. ; Ferreira, L.M.M. ; Cone, J.W. ; Marques, G.S.M. ; Barros, A.R.N. ; Rodrigues, M.A.M. - \ 2010
In vitro equine caecal fermentation of different casein levels
Santos, A.S. ; Ferreira, L.M.F. ; Cotovio, M. ; Silva, F. ; Guedes, C.M. ; Cone, J.W. ; Bessa, R.J.B. ; Rodrigues, M.A.M. - \ 2010
In: 5th European Workshop on Equine Nutrition : The impact of nutrition on the health and welfare of horses. - Wageningen : Wageningen Academic Publishers - ISBN 9789086861552 - p. 199 - 202.
Effect of collection time on the fermentative activity of equine faeces in the gas production technique
Desrousseaux, G. ; Santos, A.S. ; Pellikaan, W.F. ; Cone, J.W. ; Ferreira, L.M.M. ; Guedes, C.M. ; Rodrigues, M.A.M. - \ 2010
In: 5th European Workshop on Equine Nutrition : The impact of nutrition on the health and welfare of horses. - Wageningen : Wageningen Academic Publishers - ISBN 9789086861552 - p. 189 - 192.
Protein fermentation characteristics in rumen fluid determined with the gas production technique
Cone, J.W. ; Rodrigues, M.A.M. ; Guedes, C.M. ; Blok, M.C. - \ 2009
In: Book of abstracts of the XI the International Symposium of Ruminant Physiology,Clermont-Ferrrand, France, 6 - 9 September, 2009. - - p. 142 - 143.
Effect of collection time on the fermentative activity of enquine faeces
Desrousseaux, G. ; Santos, A.B. dos; Pellikaan, W.F. ; Cone, J.W. ; Ferreira, L.M.M. ; Guedes, C.M. ; Rodrigues, M.A.M. - \ 2009
In: Congres of Animal Production, Vila Real, Portugal, 4 - 8 May, 2009. - - p. 78 - 81.
Relationship between in situ degradation kinetics and in vitro gas production fermentation using different mathematical models
Rodrigues, M.A.M. ; Cone, J.W. ; Ferreira, L.M.M. ; Blok, M.C. ; Guedes, C. - \ 2009
Animal Feed Science and Technology 151 (2009)1-2. - ISSN 0377-8401 - p. 86 - 96.
nylon bag degradability - production profiles - ruminant feeds - rumen fermentation - dairy-cows - extent - fluid - digestibility - disappearance - prediction
In vitro and in situ studies were conducted to evaluate the influence of different mathematical models, used to fit gas production profiles of 15 feedstuffs, on estimates of nylon bag organic matter (OM) degradation kinetics. The gas production data were fitted to Exponential, Logistic, Gompertz and a Sigmoidal model. Using only gas production parameters allowed poor prediction of in situ degradation. It was not possible to estimate the washout (W) and degradable (D) in situ fractions for all models, with the exception of the Sigmoidal model with which the D fraction was poorly estimated (R2 = 0.28). The Exponential model did not show any estimation capability, and the Logistic and Gompertz models best predicted in situ degradation rate of OM (kd) with R2 values of 0.65 and 0.62, respectively. The transformation of the in situ rate of degradation (kd) to its half-life value of degradation ((ln 2/kd)100) provided an improvement of kd prediction in the Sigmoidal model, with R2 changing from 0.35 to 0.64. As to kd and fermentable organic matter (FOM) all estimations improved upon inclusion of chemical composition characteristics, such as sugars, crude protein (CP), neutral detergent fibre (NDFom) and crude fat (CFat). The Logistic and Gompertz models continued to better predict kd, with R2 values of 0.79 and 0.88, respectively, while the Sigmoidal model showed a higher capability to estimate FOM (R2 = 0.90). It should also be noticed that the estimation of the washout fraction (W) estimation was obtained with only sugar and starch contents (R2 = 0.62). There were only moderate relationships between in situ and gas production indicating that the methods do not describe the degradation of these feedstuffs in a similar way
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