scholarly journals Photoperiod influenced the growth and antioxidative responses of Chlorella vulgaris, Isochrysis galbana, and Tetraselmis chuii

Author(s):  
Yusof Nurul Shafiqa ◽  
Yeong Yik Sung ◽  
Zakeri Hazlina Ahamad ◽  
Wahid Mohd Effendy Abdul ◽  
Ghafar Sarah Nabila Ab ◽  
...  
2009 ◽  
Vol 39 (6) ◽  
pp. 1760-1767 ◽  
Author(s):  
Silvana Ohse ◽  
Roberto Bianchini Derner ◽  
Renata Ávila Ozório ◽  
Maurício Villela Da Costa Braga ◽  
Paulo Cunha ◽  
...  

O aumento da emissão de CO2 e de outros gases efeito estufa tem gerado debates em nível mundial sobre alterações climáticas e estimulado o desenvolvimento de estratégias mitigadoras. Trabalhos nessa área incluem sequestro de CO2 por meio da produção de microalgas aquáticas. Por essa razão, desenvolveu-se um estudo visando determinar os teores de carbono, hidrogênio, nitrogênio e proteína e a produção de biomassa seca de nove espécies de microalgas marinhas (Nannochloropsis oculata, Thalassiosira pseudonana, Phaeodactylum tricornutum, Isochrysis galbana, Tetraselmis suecica, Tetraselmis chuii Chaetoceros muelleri, Thalassiosira fluviatilis e Isochrysis sp.) e uma de água doce (Chlorella vulgaris), em cultivo autotrófico estacionário com objetivo de identificar as mais produtivas e com maior capacidade de fixação de carbono. O experimento foi desenvolvido em sala de cultivo, na Universidade Federal de Santa Catarina, com iluminação contínua e radiação em torno de 150µmol m-2 s-1, temperatura de 25±2°C, suplementação de ar constante, sendo utilizados erlenmeyers com 800mL de meio de cultura. O delineamento experimental foi de blocos casualizados no tempo com três repetições. As espécies C. vulgaris e T. suecica são menos produtivas. Quando se visa à suplementação alimentar, as espécies C. vulgaris e T. Chuii são consideradas interessantes, uma vez que apresentam altos teores de C, N, H e proteína. As espécies N. Oculata, T. pseudonana e C. vulgaris apresentam altos teores de C, demonstrando alta capacidade de fixação de carbono.


Author(s):  
Ita Widowati ◽  
Muhammad Zainuri ◽  
Hermien Pancasakti Kusumaningrum ◽  
Ragil Susilowati ◽  
Yann Hardivillier ◽  
...  

Processes ◽  
2021 ◽  
Vol 9 (3) ◽  
pp. 496
Author(s):  
Ignacio López Muñoz ◽  
Olivier Bernard

Dissolved oxygen plays a key role in microalgal growth at high density. This effect was so far rarely quantified. Here we propose a new model to represent the combined effect of light, oxygen concentration and temperature (LOT-model) on microalgae growth. The LOT-model introduces oxygen concentration in order to represent the oxidative stress affecting the cultures, adding a toxicity term in the expression of the net growth rate. The model was validated with experimental data for several species such as Chlorella minutissima, Chlorella vulgaris, Dunaliella salina, Isochrysis galbana. It successfully predicted experimental records with an average error lower than 5.5%. The model was also validated using dynamical data where oxygen concentration varies. It highlights a strong impact of oxygen concentration on productivity, depending on temperature. The model quantifies the sensitivity to oxidative stress of different species and shows, for example, that Dunaliella salina is much less affected than Chlorella vulgaris by oxidative stress. The modeling approach can support an optimization strategy to improve productivity, especially for managing high oxygen levels.


1986 ◽  
Vol 37 (4) ◽  
pp. 467 ◽  
Author(s):  
GH Arnott ◽  
GW Brand ◽  
LC Kos

Effects of food quality and quantity on certain fitness traits of G. pectrnatus were examined to develop methods of culture. Five generations were successfully reared on excess Isochrysis galbana, despite intense inbreeding. The effect of food quantity was tested using outcrossed offspring fed I. Galbana at four concentrations. Generation time (from hatching to egg) decreased from 43.2 days at 1 × 104 cells ml-1 (lowest concentration) to 19.6 days at 5 × 105 cells ml-1 (highest concentration). An increase occurred in female body length (0.88 to 1.01 mm) and egg number (21.2 to 51.3) with increasing food concentration, and the total number of adults produced per brood was significantly lower at 1 × 104 cells ml-1. Results on a Dunaliella tertiolecta diet were similar to those for I. Galbana at the one food concentration tested (1 × 105-2 × 105 cells ml-1); however, unlike I. galbana, D. tertiolecta did not sustain viable egg production and was therefore nutritionally inadequate for multiple generation culture. Larval mortality was high on diets of Tetraselmis chuii and Phaeodactylum tricornutum. Body lengths and egg numbers of cultured females fed I. Galbana were greater than those of the 'wild' parental females, thus indicating the suitability of the culture conditions.


2021 ◽  
Vol 26 (4) ◽  
pp. 265-270
Author(s):  
Ita Widowati ◽  
Muhammad Zainuri ◽  
Hermin Pancasakti Kusumaningrum ◽  
Yann Hardivillier

Recently, expanded consideration has been paid to the business and potentiality of microalgae. Some microalgae are at present being studied for their capacity to find important metabolites for the drug industry or aquacultural applications. Concerning these biotechnological challenges, there is a consistent exertion accommodated in both finding and taking advantage of new microalgal assets and fostering their putative business results or modern valorizations. The crude methanol extracts of three microalgae, Dunaliella salina, Tetraselmis chuii, and Isochrysis galbana, have been investigated for antibacterial activity using the disk diffusion method against aquatic pathogens of fish, shrimp, and shellfish e.g. Pseudomonas fluorescence and Vibrio harveyi. This research aimed to analyze the antibacterial activity of crude extract of these microalgae against aquatic pathogens. The disk diffusion method was used to investigate the antibacterial activity. The result showed that only T. chuii has the inhibition zone for both tested bacteria P. fluorescence and V. harveyi with the inhibition zone of 3.0 ± 0.6 mm on 100 µg. g–1 of extract concentration and 4.20 ± 1.1 mm against P. fluorescence on 10000 µg. g–1 of extract concentration. While D. salina and I. galbana have inhibition zone only for V. harveyi with the inhibition zone of 4.4 ± 0.6 mm and 3.2 ± 0.7 mm on 10000 µg. g–1 of extract concentration. These three microalgae may have potential use in aquatic pathogens as antimicrobial agents. It would be possible to develop biologically active compounds of microalgae as a functional feed for aquaculture.


BIOCELL ◽  
2018 ◽  
Vol 42 (1) ◽  
pp. 7-11 ◽  
Author(s):  
M. Moustafa ◽  
T. Taha ◽  
M. Elnouby ◽  
M.A. Abu-Saied Aied ◽  
A. Shati ◽  
...  

Sign in / Sign up

Export Citation Format

Share Document