Browsing by Author "Santander-Avanceña, Sheryll S."
Acute toxicity of water-accommodated fraction and chemically enhanced WAF of bunker C oil and dispersant to a microalga Tetraselmis tetrathele SS Santander-Avanceña, RB Sadaba, HS Taberna Jr., GT Tayo & J Koyama -
Bulletin of Environmental Contamination and Toxicology, 2016 - Springer VerlagThis study assessed the toxicity of water-accommodated fraction (WAF) and chemically enhanced WAF (CEWAF) of bunker C oil and dispersant (DISP) to a microalga, Tetraselmis tetrathele. The 72-h median effective concentration (72-h EC50) of CEWAF and DISP were determined at 3.30 % and 2.40 %, respectively. The no observed effect concentration (NOEC) of CEWAF to T. tetrathele was at 2.0 % and lowest observed effect concentration (LOEC) was at 3.0 % while NOEC and LOEC of DISP to T. tetrathele were determined at 1.0 % and 2.0 %, respectively. The addition of dispersant to oil increased the amount of total PAH present in the CEWAF test solutions. DISP alone was highly toxic, and the toxicity of CEWAF was primarily caused by the presence of dispersant.
ArticleThis study examined the effect of short-term nitrogen (N) enrichment on Gracilariopsis heteroclada growth and agar quality. Planting materials were soaked in different concentrations of ammonium chloride (NH4Cl) for 6 h. Total thallus N content was highest in Gp. heteroclada enriched in 300 mg l-1 NH4Cl. Growth experiments showed that this enrichment treatment (300 mg l-1 NH4Cl for 6 h) increased the growth of Gp. heteroclada (4.22±0.09% day-1) compared with the control (3.68±0.12% day-1). Pond culture using enriched Gp. heteroclada resulted in high growth rates (6.14±0.50% day-1). No epiphyte growth was observed during either the growth experiment or the pond culture. There were no significant differences between the agar yields of the enriched (3.65±0.36%) or control (3.78±0.18%) Gp. heteroclada. Additionally, no significant differences were detected when the gel strength of the enriched (611±22 g cm-2) and control (587±11 g cm-2) Gp. heteroclada were compared. The results suggest that the short-term N enrichment method could be an alternative culture strategy to increase Gp. heteroclada production and lower farming costs.