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espanolLos sistemas basados en el uso de microalgas para la obtencion de bioproductos son considerados un area prometedora para aplicaciones industriales. El objetivo del trabajo fue evaluar la produccion de ficobiliproteinas y clorofila-a cuando Aphanothece microscopica Nageli es cultivada en sistemas autotroficos y heterotroficos. Para ello, se desarrollaron sistemas de cultivos heterotroficos (en ausencia de luz) y autotroficos (2 klux de intensidad luminosa) en biorreactores a pH 7,6, 20 °C, 1 vvm de aireacion, empleando como medios de cultivo un efluente de industria lactea con relacion C/N 20 y N/P 10, y BG11. Inoculo inicial 200 mg/L. Se efectuo el monitoreo de concentraciones de clorofila-a y ficobiliproteinas en fase logaritmica y estacionaria. Se observaron las mayores concentraciones de pigmento en la fase logaritmica: mayores concentraciones de clorofila-a en cultivos autotroficos y predominio de aloficocianina y ficoeritrina en cultivos heterotroficos. Los resultados mostraron el efecto de las variables en estudio para la produccion de pigmentos, en la fase de crecimiento logaritmico, lo que indica la posibilidad de producir en sistemas heterotroficos de Aphanothece microscopica Nageli, aproximadamente 3.185 ton/ ano de biomasa, para 3.127 kg/ano clorofila, 232.825 kg/ano ficocianina, 47.775 kg/ano aloficocianina y 7.008 kg/ano ficoeritrina, cuando se utiliza efluente de industria lactea como medio de cultivo. EnglishThe systems that use microalgae to obtain bioproducts are considered a promising area for industrial applications. The objective of this work was to evaluate the production of phycobiliproteins and chlorophyll-a by Aphanothece microscopica Nageli, when it is cultivated in autotrophic and heterotrophic systems. Thus, the cultures were grown in heterotrophic (absence of light) and autotrophic (2 klux of light intensity) system, in bioreactors at pH 7.6, 20 oC, 1 vvm aeration, using a dairy industry effluent, with C/N 20 and N/P 10, and BG11 as culture media. Initial inoculum 200 mg/L. The concentrations of chlorophyll-a-andphycobiliproteins in logarithmic and stationary phase were monitored. The highest concentrations of pigment were observed in logarithmic phase: The highest concentrations of chlorophyll-a in autotrophic cultures, and predominance of allophycocyanin and phycoerythrin in heterotrophic cultures. The results show the effect of the variables under study for pigment production, bearing in mind the logarithmic growth phase, suggesting the possibility of producing in heterotrophic systems by Aphanothece microscopica Nageli, around 3,185 ton/year of biomass, and 3,127 kg/year of chlorophyll, 232,825 kg/year of phycocyanin, 47,775 kg/year of allophycocyanin and 7,008 kg/year of phycoerythrin, when dairy effluent is used as culture medium

The dynamic removal of different forms of dissolved and suspended phosphorus (reactive phosphorus, acid-hydrolyzable phosphorus, organic phosphorus and total phosphorus) by the cyanobacteria Aphanothece microscopica Nageli cultivated heterotrophically in dairy processing wastewater was investigated. Bioreactor performance was highly dependent on operation temperature (10–30°C). Aphanothece microscopica Nageli was able to uptake not only simple phosphorus species (reactive and acid-hydrolyzable phosphorus), but also complex fractions of organically bound phosphorus. Low bioreactor performance was evidenced by the suspended fractions. The conversion of suspended reactive phosphorus and suspended acid-hydrolyzable phosphorus varied between 50.3% and 93.3%. Suspended organic phosphorus and suspended total phosphorus became erratic, with peaks of phosphorus appearing after 8 h of hydraulic detention time and slightly impacting the global phosphorus balance. In addition to phosphorus removal, a good de...

In this paper we present and analyse single-cell oil (SCO) production through the cultivation of the cyanobacterium Aphanothece microscopica Nageli in fish processing wastewater at different temperature levels. The growth data were fitted into four mathematical models (Logistic, Gompertz, modified Gompertz and Baranyi), to define a mathematical expression for describing cell growth. Using statistical criteria, the Logistic model was considered the most adequate one to describe biomass growth. A negative relationship between the percentage of lipid and high growth temperature was evidenced. Mathematical modelling indicates the possibility of obtaining 0.26, 0.36 and 0.44 gbiomass/Lreactor day at temperatures of 10, 20 and 30 °C, respectively. This results in lipid productivity of 0.04, 0.05 and 0.03 glipid/Lreactor day at 10, 20 and 30 °C, respectively.

Laboratory experiments were performed to study the capacity of CO2 sequestration and carbon fixation into biomass during the cultivation of the cyanobacteria Aphanothece microscopica Nageli in refinery wastewater. The influence of the photoperiod (day/night) on the rates of CO2 sequestration and O2 release was also determined. Rates of CO2 sequestration were measured both in the liquid and gaseous phases. The results showed that the capacity of CO2 sequestration and O2 release during the day/night experiment was about one-fourth less than that achieved in the continuously illuminated experiment. Equivalence was found between rates of CO2 sequestration measured in the two phases. Despite large amounts of CO2 that were sequestered during the cultivation, it is demonstrated that only a small fraction (about 3%) was effectively fixed as microalgae biomass, indicating the existence of other routes of CO2 conversion in the photobioreactor.

Resumen The objective of this work was to evaluate the effect of air-drying temperature on fatty acids profile of Aphanothece microscopica Nageli microalgae and to study the effect of these parameters on the quality characteristics of the dehydrated biomass. Biomass production was carried out from wastewater of the process of rice parboiling using a bubble column bioreactor. The biomass was separated from the effluent by centrifugation and dehydrated in a tray dryer at different drying conditions. El objetivo del presente trabajo fue evaluar los cambios ocasionados por las condiciones de secado en el perfil lipidico de la biomasa en la microalga Aphanothece microscopica Nageli. La biomasa fue producida en bioreactores de columna de burbujas utilizando el efluente de la parbolizacion del arroz como medio de cultivo. La biomasa fue separada del efluente y deshidratada en un secador de bandejas bajo diferentes condiciones de secado. Palabras clave: Microalga, acidos grasos, secado

This study was undertaken to investigate the dehydration characteristics of the cyanobacterium Aphanothece microscopica Nageli in a convective hot-air dryer. The dehydration characteristics of the biomass were examined at air temperatures of 40, 50 and 60 °C and sample thicknesses of 3, 5 and 7 mm. During the dehydration experiments, air velocity was held stable at 1.5 m/s (parallel flow). The effects of air temperature and sample thickness on the dehydration characteristics and quality parameters (instrumental colour and chlorophyll a) of the dehydrated biomass were determined. The transport of water during dehydration was described by Fick's equation and effective diffusivity was between 8.1 × 10−8 and 18.8 × 10−8 m2 s−1. The experimental dehydration data on biomass obtained were fitted to the Henderson and Pabis model, and the drying rate constant was between 0.005 and 0.024 min−1. The response surface methodology was very efficient in determining product quality, showing the strong effect of temperature on instrumental colour and chlorophyll a content. The thicknesses evaluated showed a less significant effect on the final quality.

Aphanothece cf. microscopica Nägeli (1849: 59) (Figs. 1H–1I). Round colonies, 24.6–77.8 µm diam., sub-colonies often present, 8.0–12.7 µm diam. Sheath firm, hyaline, conspicuous. Cells sparsely to densely disposed, cylindrical, rarely ellipsoid, 3.1–6.0(7.2) × 1.7–2.9 µm, 1.8–2.0 times longer than wide. Cell content slightly granulated, intense blue-green. Habitat: —Waterlogged soil covered by vegetation. Notes: —The studied specimens have a cell length smaller than what is proposed by Komárek & Anagnostidis (1998). Furthermore, the habitat of Aphanothece microscopica is a little different (moorland freshwater). However, Desikachary (1959) reported the occurrence of A. microscopica in waterlogged soils from India, and Wille (1914) found this species among mosses. Studied material: — BRAZIL. São Paulo: Cananéia, State Park of “Ilha do Cardoso” (Perequê), 25º 4’ 8” S, 47º 55’ 12.24” W, 29 June 2010, W.A. Gama-Jr. & C.F.S. Malone (SP 401439)., Published as part of Jr, Watson Arantes Gama, Iv, Haywood Dail Laughinghouse & Sant'Anna, Célia Leite, 2014, How diverse are coccoid cyanobacteria? A case study of terrestrial habitats from the Atlantic Rainforest (São Paulo, Brazil), pp. 61-97 in Phytotaxa 178 (2) on page 63, DOI: 10.11646/phytotaxa.178.2.1, http://zenodo.org/record/5145178, {"references":["Nageli, C. (1849) Gattungen einzelliger Algen, physiologisch und systematisch bearbeitet. Neue Denkschriften der Allg. Schweizerischen Gesellschaft fur die Gesammten Naturwissenschaften 10 (7): 1 - 139. http: // dx. doi. org / 10.5962 / bhl. title. 6805","Komarek, J. & Anagnostidis, K. (1998) Cyanoprokaryota 1. Teil: Chroococcales. In: Ettl, H., Gartner, G., Heynig, H. & Mollenhauer D. (Eds.) Susswasserflora von Mitteleuropa 19 / 1. Fischer, Jena, 548 pp.","Desikachary, T. V. (1959) Cyanophyta. ICAR Monographs, New Delhi, 686 pp.","Wille, N. (1914) Susswasseralgen von den Samoainseln, Hawaii, den Salomonsinseln und Ceylon, gesammelt von Dr. K. Rechinger. Denkschriften der Kaiserlichen Akademie der Wissenschaften. Mathematisch-naturwissenschaftliche Klasse 91: 141 - 162."]}

Neste trabalho, a eficiência da cianobactéria Aphanothece microscopica Nägeli em remover heterotroficamente fosfato total dissolvido do efluente do processamento de laticínios foi avaliada. Os experimentos foram conduzidos em biorreatores operados descontinuamente, alimentados com 4,5 L de efluente. As condições experimentais foram: concentração celular inicial de 0,2 g/L, pH ajustado a 7,6, reator isotérmico operando em temperaturas de 10, 20 e 30ºC, ausência de luminosidade e aeração contínua de 1 VVM. Os resultados mostraram que a remoção de fosfato é fortemente dependente da temperatura do processo. A cianobactéria A. microscopica Nägelifoi efetiva na remoção de fosfato,alcançando taxas de remoção de 3,77 mg/L.h, que refletiram em conversões de 98,4% em tempos de detenção hidráulica de 24 h.

O objetivo deste trabalho foi caracterizar a solubilidade e a capacidade emulsificante da biomassa da cianobactéria Aphanothece microscopica Nägeli em diferentes condições de secagem. Produziu-se a biomassa na água residuária do processo de parboilização do arroz, inoculando 100 mg.L-1 de Aphanothece microscopica Nägeli na fase exponencial de crescimento em reator cilíndrico de mistura completa, na ausência de luz, pH 8,0, 30ºC, razão C/N 50 e tempo de detenção hidráulica de 72h. A biomassa foi separada do efluente por centrifugação e desidratada em secador descontínuo de bandejas nas condições de 40, 50 e 60ºC em espessuras de biomassa de 3, 5 e 7 mm. A solubilidade protéica foi avaliada em pH 2, 3, 4, 6, 8, 9 e 10 e a capacidade emulsificante determinada em pH 7,0. Os resultados demonstraram que as maiores solubilidades protéicas ocorreram em pH 10, havendo incremento da capacidade emulsificante nas camadas de biomassa de 3 mm de espessura.