The intracellular lipase production by
Mucor circinelloides
URM 4182 was investigated through a step-by-step strategy to attain immobilized whole-cells with high lipase activity. Physicochemical ...parameters, such as carbon and nitrogen sources, inoculum size and aeration, were studied to determine the optimum conditions for both lipase production and immobilization in polyurethane support. Olive oil and soybean peptone were found to be the best carbon and nitrogen sources, respectively, to enhance the intracellular lipase activity. Low inoculum level and poor aeration rate also provided suitable conditions to attain high lipase activity (64.8 ± 0.8 U g
−1
). The transesterification activity of the immobilized whole- cells was assayed and optimal reaction conditions for the ethanolysis of babassu oil were determined by experimental design. Statistical analysis showed that
M. circinelloides
whole-cells were able to produce ethyl esters at all tested conditions, with the highest yield attained (98.1 %) at 35 °C using an 1:6 oil-to-ethanol molar ratio. The biocatalyst operational stability was also assayed in a continuous packed bed reactor (PBR) charged with glutaraldehyde (GA) and Aliquat-treated cells revealing half-life of 43.0 ± 0.5 and 20.0 ± 0.8 days, respectively. These results indicate the potential of immobilized
M. circinelloides
URM 4182 whole-cells as a low-cost alternative to conventional biocatalysts in the production of ethyl esters from babassu oil.
This study aimed to investigate the kinetics, isotherms, and thermodynamics of biosorption of the cationic dye rhodamine B by a low-cost biosorbent prepared from
Aspergillus oryzae
cells. Culture ...medium composition (mineral salts, nitrogen source, and carbon source) influenced removal efficiency, and dye removal increased with increasing biosorbent concentrations until a plateau was reached at 10 g L
−1
. Temperature and dye concentration were directly related to removal, and the highest removal efficiency was obtained at 40 °C and 200 mg L
−1
of dye. The adsorption kinetics was best fitted to a pseudo-second-order model, and equilibrium data were well described by the Freundlich equation. Thermodynamic analysis indicated that the biosorption of rhodamine B by
A. oryzae
cells is physical in nature, spontaneous, and more favorable at higher temperatures and dye concentrations. Overall, the results suggest that inactivated
A. oryzae
biomass is a promising biosorbent for the removal of cationic dyes from wastewater.
•The potential of six non-edible feedstocks were assessed to yield biodiesel by enzymatic route.•Lipase from Burkholderia cepacia immobilized on silica-PVA was used as biocatalyst.•All feedstocks ...were found to be suitable for biodiesel production, attaining yields higher than 94.6%.•The high yields obtained enable the product to be classified as a fuel according to ASTM standards.
The focus of this work was to evaluate the potential of non-edible feedstocks to yield biodiesel by an enzymatic route. The ethanolysis of native oils from tropical crops, such as andiroba (Carapa guianensis), babassu (Orbignya sp.), jatropha (Jatropha curcas), macaw palm (Acrocomia aculeata), palm tree (Elaeis guineensis) and industrial waste (beef tallow) in solvent-free system was studied. All reactions were carried out with the microbial lipase from Burkholderia cepacia immobilized on a silica-polyvinyl alcohol matrix in a solvent-free system at 50°C for a maximum period of 24h. Under the conditions tested the biocatalyst was efficient in converting all fatty acids in the lipid feedstocks into the corresponding ethyl esters. Viscosity values for biodiesel samples obtained in each reaction (4.3 and 6.0mm2/s) showed consistent reduction in relation to their original feedstock material, which also confirms the high conversion of triglycerides to ethyl esters (>94.5%). This comparative study shows that the formation of ethyl esters from different non-edible feedstocks was feasible and can provide a considerable increase in the prospect of attaining an environmental sustainability of the process as a whole.
•The biochemical methane production were obtained from dairy wastewater treatment.•A hybrid dairy wastewater treatment (enzymatic/biological) were investigated.•The whole cells of Penicillium ...citrinum were cultivated in agroindustrial wastes.•A high cumulative methane production was reached after 45 h of treatment.
This study aimed to assess the potential of the biochemical methane production and biodegradability of dairy wastewater employing a hybrid treatment: granular anaerobic sludge as inoculum and whole cells of Penicillium citrinum with high lipase activity. It was expected that mycelium-bound lipase from whole cells would enhance hydrolysis, contributing to the efficiency of anaerobic digestion by granular inoculum. Seven substrate and microbial combinations were prepared; five contained the inoculum and whole cells cultivated in different agroindustrial wastes and two were controls (inoculated and uninoculated). A synergistic microbial interaction was evidenced by the high cumulative methane production after 45 h of reaction, reaching 231 mL g−1 volatile solids. pH was maintained at values near neutrality in all treatments, and chemical oxygen demand removal ranged from 42 to 57 % in hybrid treatments. First-order and modified Gompertz kinetic models were fitted to experimental data, and a lag phase was not observed. The results show the potential of hybrid treatment of dairy wastewater with whole cells produced in waste-based media for biogas production.
The performance of Penicillium citrinum whole cells in decreasing lipid and organic contents in dairy wastewater was investigated using sequential and simultaneous treatment processes (enzymatic ...hydrolysis and anaerobic digestion). Free and immobilized whole cells were used as catalysts for the treatment of dairy wastewater at pH 4.0, 7.0, and 8.0 (optimal pH for P. citrinum whole cell activity) for 48 h. Percent hydrolysis was higher at pH 8.0. Free whole cells achieved a 1.3-fold higher percent hydrolysis (92.5%) than immobilized whole cells. Biodegradability tests were conducted using crude wastewater (E1), wastewater prehydrolyzed by whole cells (E2), and wastewater simultaneously submitted to whole-cell hydrolysis and biodigestion (E3). Low removal of organic matter was obtained in all tests (mean of 43%). E2 and E3 resulted in higher methane production rate than E1, which demonstrates the benefits of combining enzymatic hydrolysis and anaerobic digestion for wastewater treatment, whether sequentially or simultaneously.
•Whole cells of Penicillium citrinum hydrolyzed lipids in dairy wastewater.•Free whole cells had higher hydrolysis efficiency than immobilized whole cells.•Methane production was highest with simultaneous enzymatic and biological treatment.
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► Rhizopus oryzae (URM 3231, 4692) and Mucor circinelloides (URM 4140, 4182) were considered to be good intracellular lipase producers. ► These fungi strains exhibited high lipase ...activity when immobilized in situ using polyurethane foam particles. ► M. circinelloides URM 4182 showed the highest activity towards the transesterification of babassu oil with ethanol.
The screening, biomass growth of lipase-producing fungus isolated from different sources and available at URM (University Recife Mycologia), as well as, the immobilization and utilization of the whole cells for the transesterification of babassu oil were investigated. Rhizopus oryzae (URM 3231, 4692), Mucor circinelloides (URM 4140, 4182) and Penicillium citrinum URM 4216 were considered to be good intracellular lipase producers whereas those from Mucor hiemalis URM 4144 and Mucor piriformis URM 4145 were weaker. Fungi biomass containing high lipase activities was immobilized on different biomass support particles (BSPs) and with the exception of Penicillium citrinum URM 4216 all the other fungi strains exhibited high lipase activity (20–50Ug−1) when immobilized in situ using polyurethane foam particles. Transesterification activities of the immobilized whole cells were evaluated in the ethanolysis reaction with babassu oil and the highest performance was attained by M. circinelloides URM 4182 giving 83.22±3.68% ester yield in less than 96h reaction. The biocatalyst operational stability was also assessed and an inactivation profile was found to follow the Arrhenius model, revealing values of 26 days and 2.6×10−2day−1, for half-life and a deactivation coefficient, respectively. The purified product (biodiesel) exhibited viscosity (6.63 cSt) close to the value to attend specifications by the ASTM D6751 to be used as biofuel. Results are favorable compared with data already reported in the literature and demonstrated that M. circinelloides URM 4182 whole cells is a cheaper biocatalyst that can be used in the biodiesel synthesis.
Mycelium-bound lipase from filamentous fungus has been extensively studied as an alternative biocatalyst used in biotransformation processes. In this work, Penicillium citrinum URM 4216 was assessed ...as a potential producer of mycelium-bound lipase and its catalytic activity was investigated to yield concentrated polyunsaturated fatty acids from vegetable oils. Under the established growth conditions and using olive oil as an inducer, P. citrinum was able to produce lipase having high mycelium-bound activity (271.67 ± 10.47 U g−1) revealing suitable biochemical (optimum pH = 8.0 at 45 °C) and kinetic (Km = 136.51 μmol L−1min−1, Vmax = 267.33 μmol g−1min−1) properties and thermal stability (half-life time of 1.8 h at 60 °C) to mediate biotransformation reactions. By applying factorial design, the hydrolysis of soybean oil yielded 38% at 38 °C using oil/buffer ratio of 20% in the presence of 2.5% of an emulsifying agent for 3 h. The hydrolysis degree was increased to 96% by replacing the conventional heating system for ultrasonic irradiation and increasing the incubation time to 9 h. Similar degrees of hydrolysis (>84%) were achieved using other rich polyunsaturated vegetable oils (sunflower, olive and canola oils); confirming the specificity of this mycelium-bound lipase for polyunsaturated fatty acids, such as oleic and linoleic acids.
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•The mycelium-bound lipase production by P. citrinum was investigated.•P. citrinum is a good biocatalyst due to its biochemical and kinetic properties.•Mycelium bound lipase of P. citrinum was able to hydrolyze different vegetable oils.•Ultrasonic irradiation without emulsifier improved the percentage of hydrolysis.•P. citrinum whole-cell lipase was selective for polyunsaturated fatty acids.
Plant growth on harsh substrates (habitat specialization) requires specific traits to cope with stressful conditions.
We tested whether traits related to nutrient acquisition (root colonization by ...fungal symbionts, and plant morphological and physiological specializations), and nutrient use (leaf nitrogen (N) and phosphorus (P) concentrations and N‐ and P‐remobilization efficiency), were related to habitat specialization for 27 species of Velloziaceae growing either in soil or on rocks in extremely P‐impoverished campos rupestres habitats. If habitat specialization were to drive trait sorting, then we expect traits to differ between those substrates.
Both soil and rock‐dwelling species presented a very low proportion of root length colonized by arbuscular mycorrhizal and dark‐septate fungi. However, rhizosheaths were only observed in soil‐dwelling species, and vellozioid roots, a specialization that allows for mining P and dissolving quartzite rock, were mostly found in rock‐dwelling species. We did not observe differences in nutrient‐use traits between rock‐ and soil‐dwelling species.
Root specializations are strongly correlated with microhabitats, and the presence of vellozioid roots seems to mediate bare rock specialization. There is an overall P limitation of plant productivity both on rock and in soil of campos rupestres, which does not drive the sorting of traits related to above‐ground nutrient use and symbiotic P acquisition. Therefore, nutrient impoverishment is indeed a very strong environmental filter in campos rupestres as a whole, but habitat specialization plays an important role in the spatial distribution of Velloziaceae between contrasting substrates.
Translated
Resumo
O crescimento de plantas sobre substratos considerados estressantes (especialização de habitat) requer atributos específicos das plantas.
Nós testamos se os atributos relacionados à aquisição de nutrientes (colonização das raízes por fungos simbióticos, especializações morfológicas e fisiológicas das plantas), e ao uso de nutrientes (concentração foliar de nitrogênio (N) e fósforo (P) e eficiência de remobilização de N e P) estavam relacionados com a especialização de habitat. Nós analisamos os atributos em 27 espécies de Velloziaceae que crescem sobre solo ou rocha em campos rupestres extremamente empobrecidos em P. Se a especialização de habitat fosse responsável pela diferenciação dos atributos, então nós esperaríamos que os atributos diferissem entre esses substratos.
Tanto as espécies que crescem sobre solo, quanto as que crescem sobre rocha apresentaram uma proporção muito pequena da raiz colonizada por micorrizas arbusculares e fungos endofíticos melanizados (“dark septate”). No entanto, somente observamos areia aderida às raízes (“rhizosheaths”) nas plantas que crescem sobre solo. As raízes velozióides, uma especialização que permite a dissolução da rocha e a subsequente aquisição de P, foram observadas principalmente nas espécies crescendo sobre rochas. Nós não observamos diferenças entre os atributos relacionados ao uso de nutrientes entre espécies crescendo sobre os diferentes tipos de substrato.
Especializações radiculares apresentaram forte correlação com o microhabitat, e a presença de raízes velozióides parece mediar a especialização no crescimento sobre a rocha nua. Em campos rupestres, existe uma limitação generalizada do crescimento vegetal pela baixa concentração de P, tanto no solo quanto sobre as rochas, o que não resultou em diferenças nos atributos foliares associados com o uso de N e P. Portanto, a escassez de nutrientes constitui de fato um forte filtro ambiental em campos rupestres como um todo, mas a especialização de habitat tem um papel importante na distribuição de espécies das Velloziaceae em substratos contrastantes.
A free Plain Language Summary can be found within the Supporting Information of this article.
A free Plain Language Summary can be found within the Supporting Information of this article.
The aim of this work was the preparation and application of highly hydrophobic epoxy–chitosan/alginate as a support to immobilize microbial lipases from Thermomyces lanuginosus commercially available ...as Lipolase® (TLL1) and Lipex® 100L (TLL2) and Pseudomonas fluorescens (PFL). The catalytic properties of the biocatalysts were assayed in olive oil hydrolysis and butyl butyrate synthesis. The results indicated that 12h was enough for TLL1 to be immobilized on the support. Covalent attachment of TLL1 turned biocatalysts highly active and around 6-fold more stable than free lipase. Based on the results, a time of incubation of 24h was selected for further studies about the maximum immobilized protein amount and butyl butyrate synthesis. Maximum protein loading immobilized was found to be 25.4mgg−1support for TLL1, followed by TLL2 (20.5mgg−1) and PFL (15.5mgg−1) offering 80mgproteing−1support. The immobilization of TLL1 and TLL2 resulted in highly active biocatalysts (around 1300IUg−1gel), almost fivefold higher than PFL (272.4IUg−1gel). In butyl butyrate synthesis, PFL showed similar activity to TLL1 and TLL2 derivatives, up to 60mmolL−1. The biocatalysts displayed high activity after five successive cycles, retaining around 95% of the initial activity.
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