Changes in fatty acid in Tecoma stans grown in mine residues after compost amendment.

Amendment tailing heaps with compost may deplete metal(loid)s concentration and improve the conditions for plant development. This research aimed to compare the Tecoma stans ability to grow on soil from the Sonora desert and mining waste (MW) after amendment with compost. Amendment the MW, with compost, decreased soluble As, Cd, Cu, Mn, Pb, and Zn up to 47, 33, 11, 34, 69, and 34%, respectively; increased ten times the leaves weight, and thirteen times the leaf area of the plants. Arsenic, Cd, Pb, Cu, and Zn in plants tissues decreased 27, 28, 27, 12, and 11%, respectively. The bioaccumulation and translocation factors were lower than one, so T. stans do not accumulate these elements. Polyunsaturated fatty acids 18:2ω6 and 18:3ω3 were increased, suggesting lower alteration of thylakoidal membrane integrity due to compost treatment. But, the amendment to the tailing was not enough to deplete the abiotic stress.

Amendment mine tailing with vermicompost depletes changes in polyunsaturated fatty acid of Tecoma stans.

Deesterification of astaxanthin and intermediate esters from Haematococcus pluvialis subjected to stress.

Haematococcus pluvialis is the richest biological source of astaxanthin under unfavorable growing conditions. Many reports have discussed the optimal astaxanthin extraction methods. Free-astaxanthin could be still hindered by microalgae extracts composition or by prolonged extraction times. In this study we evaluated the effect of enzymolysis and saponification deesterification processes of astaxanthin and its carotenoid precursors under high irradiance and nitrogen deprivation stress time conditions. Results showed that cholesterol esterase facilitated astaxanthin deesterification (975.65 µg mg-1 DW) while saponification positively affected zeaxanthin (1038.68 µg mg-1 DW).

Involvement of OpsLTP1 from Opuntia streptacantha in abiotic stress adaptation and lipid metabolism.

Plant lipid transfer proteins (LTPs) exhibit the ability to transfer lipids between membranes in vitro, and have been implicated in diverse physiological processes associated to plant growth, reproduction, development, biotic and abiotic stress responses. However, their mode of action is not yet fully understood. To explore the functions of the OpsLTP1 gene encoding a LTP from cactus pear Opuntia streptacantha Lem., we generated transgenic Arabidopsis thaliana (L.) Heynh. plants to overexpress OpsLTP1 and contrasted our results with the loss-of-function mutant ltp3 from A. thaliana under abiotic stress conditions. The ltp3 mutant seeds showed impaired germination under salt and osmotic treatments, in contrast to OpsLTP1 overexpressing lines that displayed significant increases in germination rate. Moreover, stress recovery assays showed that ltp3 mutant seedlings were more sensitive to salt and osmotic treatments than wild-type plants suggesting that AtLTP3 is required for stress-induced responses, while the OpsLTP1 overexpressing line showed no significant differences. In addition, OpsLTP1 overexpressing and ltp3 mutant seeds stored lower amount of total lipids compared with wild-type seeds, showing changes primarily on 16C and 18C fatty acids. However, ltp3 mutant also lead changes in lipid profile and no over concrete lipids which may suggest a compensatory activation of other LTPs. Interestingly, linoleic acid (18:2ω6) was consistently increased in neutral, galactoglycerolipids and phosphoglycerolipids of OpsLTP1 overexpressing line indicating a role of OpsLTP1 in the modulation of lipid composition in A. thaliana.

Producción de pigmentos procedentes de Arthrospira maxima cultivada en fotobiorreactores / Production of pigments from Arthrospira maxima cultivated in photobioreactors

RESUMEN El cultivo de cianobacterias, como Arthrospira, puede realizarse en sistemas abiertos y sistemas cerrados o fotobiorreactores. El objetivo de la presente investigación fue evaluar la producción de pigmentos de Arthrospira maxima cultivada en dos tipos de fotobiorreactores. El cultivo se realizó de forma discontinua (Batch) bajo ambiente controlado, en fotobiorreactores helicoidales y cilíndricos, durante 30 días, en medio Zarrouk. La determinación de los pigmentos se realizó en las fases de crecimiento exponencial y estacionario. Para los pigmentos liposolubles, la biomasa se sometió a extracción con acetona 90%, y posterior determinación por Cromatografía Líquida de Alta Eficiencia, y para la extracción de los pigmentos ficobiliproteínicos se ensayaron cuatro métodos: 1. regulador de fosfatos/enzimas; 2. solución alcalina, previo tratamiento con CaCl2; 3. buffer de fosfato, previo tratamiento con hielo seco y 4. agua (4ºC), y posterior determinación por Espectrofotometría UV-Visible. Los mayores valores de pigmentos liposolubles fueron obtenidos en los cultivos realizados en fotobiorreactor helicoidal durante la fase exponencial (clorofila a 11,08±0,006 µg mL-1; β-caroteno 1,82±0,003 µg mL-1; zeaxantina 0,72±0,002 µg mL-1); mientras que los mayores contenidos de los pigmentos ficobiliproteínicos se obtuvieron en fotobiorreactor cilíndrico, durante la fase estacionaria, utilizando el buffer de fosfato tratado con hielo seco para la extracción. Dentro de las ficobiliproteínas, fue la ficocianina la que se encontró en mayor proporción (FC = 77,74±0,767 mg L-1), seguido por la aloficocianina y ficoeritrina. Se concluye que la biomasa de Arthrospira maxima presenta potencial biotecnológico por sus altos contenidos de pigmentos.

ABSTRACT The culture of the cyanobacteria Arthrospira maxima can be done in open systems and closed systems or photobioreactors. The objective of the present research was to evaluate the pigment production of Arthrospira maxima grown on two types of photobioreactors. Batch system culture with Zarrouk´s medium was carried out under controlled conditions in a helicoidal and cylindrical photobioreactors during 30 days. Pigments determination was carried out in exponential and stationary growth phases. Biomass was extracted with 90% acetone, and the liposoluble pigments were injected in a HPLC. For the phycobiliprotein pigments extractions, four methods were tested: 1.- phosphate regulator/enzyme, 2.- alkaline solution, after treatment with CaCl2; 3.- phosphate buffer, previous treatment with dry ice, and 4.- water (4 °C), and subsequent determination by UV-Visible Spectrophotometry. The highest pigments content was obtained in the helicoidal photobioreactor cultures during the exponential phase (chlorophyll a 11.08±0.006 μg mL-1, β-carotene 1.82±0.003 μg mL-1, zeaxanthin 0.72±0.002 μg mL-1). Moreover, the highest contents of phycobilipretein pigments were obtained in a cylindrical photobioreactor, during the stationary phase, with phosphate buffer with dry ice extraction. Among the phycobiliproteins, the phycocyanin was in highest content (77.74±0.767 mg L-1), followed by allophycocyanin and phycoerythrin. It is concluded that the biomass of Arthrospira maxima presents biotechnological potential due to its high pigment contents.

[Growth and biochemical composition of thalassiosira pseudonana (Thalassiosirales: Thalassiosiraceae) cultivated in semicontinuous system at different culture media and irradiances]. / Crecimiento y composición bioquímica de Thalassiosira pseudonana (Thalassiosirales: Thalassiosiraceae) bajo cultivo semi-continuo en diferentes medios y niveles de irradiancias.

Thalassiosira pseudonana is a marine Bacillariophyta commonly used as live feed in mariculture. The growth rate and biochemical composition of microalgae are highly influenced by environmental factors such as, irradiance and nutrient availability. The aim of this study was to investigate the influence of three irradiances (60, 120 and 180 microE/m2.s) and two culture media (Algal and Humus) on growth and biochemical composition of this diatom. The microalga was grown semicontinuously at a daily renewal rate of fresh media of 30%, 37 per thousand salinity, 25 +/- 1 degree C and constant aeration (200 mL/min). The cell densities (cel/mL) and contents of protein, lipid, carbohydrate, chlorophyll a, total carotenoids, and fatty acids, showed significant differences (p < 0.05) between treatments. During steady-state phase, the maximal cell density, and lipid and carbohydrate contents were of 4.62 x 10(6) cel/mL, 20.3 +/- 2.28% and 16.6 +/- 2.43%, respectively, and were achieved in Humus medium at 180 microE/ m2.s. Moreover, highest protein contents (45.0 +/- 5.05%) and total carotenoids (0.5 +/- 0.01%) were obtained in Algal medium at 180 microE/m2.s. Chlorophyll a (0.93 +/- 0.04%) was higher at low irradiances in Algal medium. In both media, the fatty acids unsaturation degree was lower with increasing irradiance, being eicosapentaenoic acid, 20:5 n-3 (EPA) most represented (6.20%) in Algal medium at 60 microE/m2.s. This strain of T. pseudonana showed multiple physiological responses to changes in culture conditions, and may be cultivated with an alternative medium, which reduced the operating costs and allowed a high nutritional biomass production value for animals under culture.

Crecimiento y composición bioquímica de Thalassiosira pseudonana (Thalassiosirales: Thalassiosiraceae) bajo cultivo semi-continuo en diferentes medios y niveles de irradiancias / Growth and biochemical composition of Thalassiosira pseudonana (Thalassiosirales: Thalassiosiraceae) cultivated in semicontinuous system at different culture media and irradiances

Thalassiosira pseudonana is a marine Bacillariophyta commonly used as live feed in mariculture. The growth rate and biochemical composition of microalgae are highly influenced by environmental factors such as, irradiance and nutrient availability. The aim of this study was to investigate the influence of three irradiances (60, 120 and 180μE/m².s) and two culture media (Algal and Humus) on growth and biochemical composition of this diatom. The microalga was grown semicontinuously at a daily renewal rate of fresh media of 30%, 37‰ salinity, 25±1ºC and constant aeration (200mL/min). The cell densities (cel/mL) and contents of protein, lipid, carbohydrate, chlorophyll a, total carotenoids, and fatty acids, showed significant differences (p<0.05) between treatments. During steady-state phase, the maximal cell density, and lipid and carbohydrate contents were of 4.62x10(6)cel/mL, 20.3±2.28% and 16.6±2.43%, respectively, and were achieved in Humus medium at 180μE/m².s. Moreover, highest protein contents (45.0±5.05%) and total carotenoids (0.5±0.01%) were obtained in Algal medium at 180μE/m².s. Chlorophyll a (0.93±0.04%) was higher at low irradiances in Algal medium. In both media, the fatty acids unsaturation degree was lower with increasing irradiance, being eicosapentaenoic acid, 20:5 n-3 (EPA) most represented (6.20%) in Algal medium at 60μE/m².s. This strain of T. pseudonana showed multiple physiological responses to changes in culture conditions, and may be cultivated with an alternative medium, which reduced the operating costs and allowed a high nutritional biomass production value for animals under culture.

Thalassiosira pseudonana es utilizada como alimento en acuicultura, pero su valor nutricional está influenciado por las condiciones de crecimiento. Sistemas semicontinuos, en fase de estabilización, con tres irradiancias (60, 120 y 180μE/m².s) y dos medios de cultivo (Algal y Humus) fueron las condiciones en las que se determinó el crecimiento y componentes bioquímicos de T. pseudonana. En Humus a 180μE/m².s se obtuvieron las máximas densidades celulares (entre 3.86 y 4.62x10(6)cel/mL) y mayores concentraciones de lípidos y carbohidratos, con porcentajes de 20.3±2.28 y 16.6±2.43, respectivamente. A 180μE/m².s en Algal se observaron los mayores valores de proteínas (45.0±5.05) y carotenoides totales (0.5±0.01). El contenido de clorofila a fue favorecido por baja intensidad de luz, principalmente en Algal, con máximos de 0.9±0.04%. El grado de insaturación de los ácidos grasos disminuyó por incremento de la irradiancia en ambos medios, estando mayoritariamente representados por el ácido eicosapentaenoico, 20:5 n-3 (AEP), con porcentajes máximos (6.20%) en Algal a 60μE/m².s. Los resultados muestran múltiples respuestas fisiológicas de T. pseudonana frente a cambios en las condiciones de crecimiento, las cuales pueden ser aprovechadas para mejorar su valor nutricional como alimento de organismos cultivados, utilizando medios de cultivo alternativos, que disminuyan los costos en la producción microalgal.

Pastas de Rhodomonas salina (Cryptophyta) como alimento para Brachionus plicatilis (Rotifera)

Rhodomonas salina (Cryptophyta) pastes as feed for Brachionus plicatilis (Rotifera). Rotifers are an important live feed for first feeding larvae of many fish species. The use of concentrated algae cells in the mass culture of the rotifer Brachionus plicatilis (Brachionidae) has opened new horizons for research on this organism. Pastes of Rhodomonas salina (Pyrenomonadaceae) obtained either by centrifugation or flocculation with chitosan were preserved, with or without vitamin C, at -20°C for four weeks and were evaluated biochemically (proteins, lipids, pigments and fatty acids contents) and subsequently, were used to feed the rotifer Brachionus plicatilis at a ratio of 25mg/L/day. Four different microalgae pastes were prepared: (1) centrifuged and preserved with vitamin C (CV), (2) centrifuged and preserved without vitamin C (C), (3) flocculated and with vitamin C (FV) and (4) flocculated without vitamin C (F). All treatments showed similar contents of proteins and total lipids with respect to control culture (a fresh culture of R. salina), with mean values of 40.0±2.32% and 12.0±1.45%, respectively. The pheophytin a/chlorophyll a ratio, a general indicator of the chemical status of microalgal concentrates, was similar (0.09-0.11) between centrifuged pastes and control culture, but was found to be higher in flocculated pastes (1.28-1.48). The fatty acid profile varied with respect to the control culture, mainly in the proportion of the essential polyunsaturated fatty acids (PUFAs): eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA). Total PUFAs, EPA and DHA contents were statistically similar between centrifuged pastes and control culture (PUFAs: 47%, EPA: 4% and DHA: 4.7%), whereas values obtained for flocculated pastes were significantly lower. The rotifers grew equally well when fed with centrifuged pastes or control culture (maximum density: 320rotifers/mL; instantaneous growth rate: 0.23rotifers/day, fecundity: 1.49eggs/female and productivity: 43x103rotifers/L/day. No significant effect of vitamin C was found when used as a paste preservative. We concluded that centrifugation is an effective harvesting method, and that freezing to -20ºC for four weeks (no vitamin added), may help maintain the nutritional quality of R. salina paste, similar to fresh microalgae and can be offered to Brachionus plicatilis. Rev. Biol. Trop. 59 (4): 1503-1515. Epub 2011 December 01.

Pastas de Rhodomonas salina, obtenidas mediante centrifugación y floculación con quitosano y preservadas con o sin vitamina C, a -20°C fueron evaluadas bioquímicamente y proporcionadas como alimento al rotífero Brachionus plicatilis. Las pastas microalgales: (1) centrifugada y con vitamina C (CV), (2) centrifugada y sin vitamina C (C), (3) floculada y con vitamina C (FV) y (4) floculada y sin adición de vitamina C (F); mantuvieron sus contenidos de proteínas y lípidos totales similares al cultivo control, con valores de 40.0±2.32% y 12.0±1.45%, respectivamente. La relación feofitina a/clorofila a fue similar (0.09-0.11) entre las pastas centrifugadas y el cultivo control, pero mayor en las pastas floculadas (1.28-1.48). Las pastas centrifugadas presentaron porcentajes de PUFAs totales, EPA y DHA similares al cultivo control (PUFAs: 47%, EPA: 4% y DHA: 4.7%) y superiores al de las pastas floculadas. Las pastas obtenidas por centrifugación indujeron un crecimiento del rotífero igual al obtenido con el alimento control (densidad máxima: 320rotíferos/mL; tasa instantánea de crecimiento: 0.23rotíferos/día, fecundidad: 1.49huevos/ hembra y productividad: 43x103rotíferos/L/día). Se concluye que la pasta de R. salina centrifugada y congelada a -20°C, durante cuatro semanas, sin adición de vitamina C, mantiene su calidad nutricional similar a la del alga fresca y puede ser usada como alimento de Brachionus plicatilis.

[Rhodomonas salina (Cryptophyta) pastes as feed for Brachionus plicatilis (Rotifera)]. / Pastas de Rhodomonas salina (Cryptophyta) como alimento para Brachionus plicatilis (Rotifera).

Rotifers are an important live feed for first feeding larvae of many fish species. The use of concentrated algae cells in the mass culture of the rotifer Brachionus plicatilis (Brachionidae) has opened new horizons for research on this organism. Pastes of Rhodomonas salina (Pyrenomonadaceae) obtained either by centrifugation or flocculation with chitosan were preserved, with or without vitamin C, at -20 degrees C for four weeks and were evaluated biochemically (proteins, lipids, pigments and fatty acids contents) and subsequently, were used to feed the rotifer Brachionus plicatilis at a ratio of 25 mg/L/day. Four different microalgae pastes were prepared: (1) centrifuged and preserved with vitamin C (CV), (2) centrifuged and preserved without vitamin C (C), (3) flocculated and with vitamin C (FV) and (4) flocculated without vitamin C (F). All treatments showed similar contents of proteins and total lipids with respect to control culture (a fresh culture of R. salina), with mean values of 40.0 +/- 2.32% and 12.0 +/- 1.45%, respectively. The pheophytin a/chlorophyll a ratio, a general indicator of the chemical status of microalgal concentrates, was similar (0.09-0.11) between centrifuged pastes and control culture, but was found to be higher in flocculated pastes (1.28-1.48). The fatty acid profile varied with respect to the control culture, mainly in the proportion of the essential polyunsaturated fatty acids (PUFAs): eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA). Total PUFAs, EPA and DHA contents were statistically similar between centrifuged pastes and control culture (PUFAs: 47%, EPA: 4% and DHA: 4.7%), whereas values obtained for flocculated pastes were significantly lower. The rotifers grew equally well when fed with centrifuged pastes or control culture (maximum density: 320 rotifers/mL; instantaneous growth rate: 0.23 rotifers/day, fecundity: 1.49 eggs/female and productivity: 43 x 10(3) rotifers/L/day. No significant effect of vitamin C was found when used as a paste preservative. We concluded that centrifugation is an effective harvesting method, and that freezing to -20 degrees C for four weeks (no vitamin added), may help maintain the nutritional quality of R. salina paste, similar to fresh microalgae and can be offered to Brachionus plicatilis.