| Name: | Description: | Size: | Format: | |
|---|---|---|---|---|
| 8.32 MB | Adobe PDF |
Authors
Advisor(s)
Abstract(s)
O presente trabalho tem como objetivo o cultivo da microalga Chlorella zofingiensis, e a
avaliação da sua potencial aplicação na produção de biodiesel e de produtos de valor
acrescentado, de entre os quais se destacam os antioxidantes.
Com o intuito da produção de biocombustível é necessário efetuar o cultivo da microalga num
volume que permita a obtenção de elevada quantidade de biomassa para a concretização do
trabalho. Além deste biocombustível, existe ainda a possibilidade de valorização de alguns
produtos com valor comercial, como é o caso da astaxantina, a saber na área farmacêutica,
alimentar ou até mesmo cosmética.
O cultivo da microalga foi feito em meio Bold’s Basal Medium (BBM), inicialmente em matrazes
de 5 L e, quando se obteve uma cultura suficientemente densa, inocularam-se fotobiorreatores
de 50 L.
Conseguiu-se atingir uma concentração máxima de 0,76 g/L, no reator de 5 L, após cerca de
6 semanas de ensaio. Por sua vez, em fotobiorreatores de 50 L, a concentração máxima
obtida foi de 0,4 g/L, após 4 semanas de ensaio.
Nestas culturas foi possível obter-se uma percentagem lipídica de 7 %, apresentado
concentração de pigmentos por litro de cultura na ordem dos 10 mg/L, 4 mg/L e 2 mg/L de
clorofila a, clorofila b e carotenoides totais, respetivamente.
Com esta percentagem lipídica recuperaram-se 400 mg de óleo, obtendo-se posteriormente
280 mg de biodiesel. Pela análise à amostra de biodiesel obtida foi possível obter o perfil
lipídico desta microalga, quando cultivada em meio BBM, sendo 41% de ácido palmítico
(C16:0), 9% de ácido esteárico (C18:0), 27% de ácido oleico (C18:1) e 23% de ácido linoleico
(C18:2).
Os resultados obtidos mostram que a Chlorella zofingiensis é uma microalga com interesse
potencial para a produção de clorofila e carotenóides, mas não para o óleo para a produção
de biodiesel.
This work aims at the cultivation of Chlorella zofingiensis, a microalga with potential application in the production of biodiesel and value added products, among which the antioxidants stand out. For biofuel production it is necessary to cultivate this microalga in a volume that allows to obtain high amount of biomass for extracting enough oil for completing the work. Besides biodiesel, there is the possibility of recovering some products of commercial value, such as astaxanthin, for use namely in the pharmaceutical area, food or even cosmetics industries. The cultivation of the microalga was done using Bold's Basal Medium (BBM) initially in 5 L flasks and when a sufficiently dense culture was reached it was used to inoculate 50 L photobioreactors. It was possible to reach a maximum concentration of 0.76 g / L in a 5 L reactor after about 6 weeks assay. On the other hand, in 50 L photobioreactors, the maximum concentration achieved was 0.4 g / L after 4 weeks of testing. From these cultures it was possible to obtain a lipid percentage of 7%, and a pigment concentration in the order of 10 mg / L, 4 mg / L and 2 mg / L of chlorophyll a, chlorophyll b and carotenoids, respectively. For this culture with this lipid percentage it was obtained 400 mg of oil, yielding 280 mg of biodiesel after transesterification. The analysis of the biodiesel sample obtained allowed to get the lipid profile of this microalga, when cultivated in BBM medium, having 41% palmitic acid (C16:0), 9% stearic acid (C18:0), 27% oleic acid (C18:1) and 23% linoleic acid (C18:2). The results obtained show that Chlorella zofingiensis is a microalga with potential interest for chlorophyll and carotenoids production but not for oil for biodiesel production.
This work aims at the cultivation of Chlorella zofingiensis, a microalga with potential application in the production of biodiesel and value added products, among which the antioxidants stand out. For biofuel production it is necessary to cultivate this microalga in a volume that allows to obtain high amount of biomass for extracting enough oil for completing the work. Besides biodiesel, there is the possibility of recovering some products of commercial value, such as astaxanthin, for use namely in the pharmaceutical area, food or even cosmetics industries. The cultivation of the microalga was done using Bold's Basal Medium (BBM) initially in 5 L flasks and when a sufficiently dense culture was reached it was used to inoculate 50 L photobioreactors. It was possible to reach a maximum concentration of 0.76 g / L in a 5 L reactor after about 6 weeks assay. On the other hand, in 50 L photobioreactors, the maximum concentration achieved was 0.4 g / L after 4 weeks of testing. From these cultures it was possible to obtain a lipid percentage of 7%, and a pigment concentration in the order of 10 mg / L, 4 mg / L and 2 mg / L of chlorophyll a, chlorophyll b and carotenoids, respectively. For this culture with this lipid percentage it was obtained 400 mg of oil, yielding 280 mg of biodiesel after transesterification. The analysis of the biodiesel sample obtained allowed to get the lipid profile of this microalga, when cultivated in BBM medium, having 41% palmitic acid (C16:0), 9% stearic acid (C18:0), 27% oleic acid (C18:1) and 23% linoleic acid (C18:2). The results obtained show that Chlorella zofingiensis is a microalga with potential interest for chlorophyll and carotenoids production but not for oil for biodiesel production.
Description
Keywords
Astaxantina Biodiesel Biomassa Chlorella zofingiensis Microalga Astaxanthin Biomass Microalgae